1/*
2 *   This file is provided under a GPLv2 license.  When using or
3 *   redistributing this file, you may do so under that license.
4 *
5 *   GPL LICENSE SUMMARY
6 *
7 *   Copyright (C) 2016-2018 T-Platforms JSC All Rights Reserved.
8 *
9 *   This program is free software; you can redistribute it and/or modify it
10 *   under the terms and conditions of the GNU General Public License,
11 *   version 2, as published by the Free Software Foundation.
12 *
13 *   This program is distributed in the hope that it will be useful, but
14 *   WITHOUT ANY WARRANTY; without even the implied warranty of
15 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
16 *   Public License for more details.
17 *
18 *   You should have received a copy of the GNU General Public License along
19 *   with this program; if not, one can be found http://www.gnu.org/licenses/.
20 *
21 *   The full GNU General Public License is included in this distribution in
22 *   the file called "COPYING".
23 *
24 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
25 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
26 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
27 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
28 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
29 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
30 *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
31 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
32 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
34 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35 *
36 * IDT PCIe-switch NTB Linux driver
37 *
38 * Contact Information:
39 * Serge Semin <fancer.lancer@gmail.com>, <Sergey.Semin@t-platforms.ru>
40 */
41
42#include <linux/stddef.h>
43#include <linux/types.h>
44#include <linux/kernel.h>
45#include <linux/bitops.h>
46#include <linux/sizes.h>
47#include <linux/module.h>
48#include <linux/moduleparam.h>
49#include <linux/init.h>
50#include <linux/interrupt.h>
51#include <linux/spinlock.h>
52#include <linux/mutex.h>
53#include <linux/pci.h>
54#include <linux/aer.h>
55#include <linux/slab.h>
56#include <linux/list.h>
57#include <linux/debugfs.h>
58#include <linux/hwmon.h>
59#include <linux/hwmon-sysfs.h>
60#include <linux/ntb.h>
61
62#include "ntb_hw_idt.h"
63
64#define NTB_NAME	"ntb_hw_idt"
65#define NTB_DESC	"IDT PCI-E Non-Transparent Bridge Driver"
66#define NTB_VER		"2.0"
67#define NTB_IRQNAME	"ntb_irq_idt"
68
69MODULE_DESCRIPTION(NTB_DESC);
70MODULE_VERSION(NTB_VER);
71MODULE_LICENSE("GPL v2");
72MODULE_AUTHOR("T-platforms");
73
74/*
75 * NT Endpoint registers table simplifying a loop access to the functionally
76 * related registers
77 */
78static const struct idt_ntb_regs ntdata_tbl = {
79	{ {IDT_NT_BARSETUP0,	IDT_NT_BARLIMIT0,
80	   IDT_NT_BARLTBASE0,	IDT_NT_BARUTBASE0},
81	  {IDT_NT_BARSETUP1,	IDT_NT_BARLIMIT1,
82	   IDT_NT_BARLTBASE1,	IDT_NT_BARUTBASE1},
83	  {IDT_NT_BARSETUP2,	IDT_NT_BARLIMIT2,
84	   IDT_NT_BARLTBASE2,	IDT_NT_BARUTBASE2},
85	  {IDT_NT_BARSETUP3,	IDT_NT_BARLIMIT3,
86	   IDT_NT_BARLTBASE3,	IDT_NT_BARUTBASE3},
87	  {IDT_NT_BARSETUP4,	IDT_NT_BARLIMIT4,
88	   IDT_NT_BARLTBASE4,	IDT_NT_BARUTBASE4},
89	  {IDT_NT_BARSETUP5,	IDT_NT_BARLIMIT5,
90	   IDT_NT_BARLTBASE5,	IDT_NT_BARUTBASE5} },
91	{ {IDT_NT_INMSG0,	IDT_NT_OUTMSG0,	IDT_NT_INMSGSRC0},
92	  {IDT_NT_INMSG1,	IDT_NT_OUTMSG1,	IDT_NT_INMSGSRC1},
93	  {IDT_NT_INMSG2,	IDT_NT_OUTMSG2,	IDT_NT_INMSGSRC2},
94	  {IDT_NT_INMSG3,	IDT_NT_OUTMSG3,	IDT_NT_INMSGSRC3} }
95};
96
97/*
98 * NT Endpoint ports data table with the corresponding pcie command, link
99 * status, control and BAR-related registers
100 */
101static const struct idt_ntb_port portdata_tbl[IDT_MAX_NR_PORTS] = {
102/*0*/	{ IDT_SW_NTP0_PCIECMDSTS,	IDT_SW_NTP0_PCIELCTLSTS,
103	  IDT_SW_NTP0_NTCTL,
104	  IDT_SW_SWPORT0CTL,		IDT_SW_SWPORT0STS,
105	  { {IDT_SW_NTP0_BARSETUP0,	IDT_SW_NTP0_BARLIMIT0,
106	     IDT_SW_NTP0_BARLTBASE0,	IDT_SW_NTP0_BARUTBASE0},
107	    {IDT_SW_NTP0_BARSETUP1,	IDT_SW_NTP0_BARLIMIT1,
108	     IDT_SW_NTP0_BARLTBASE1,	IDT_SW_NTP0_BARUTBASE1},
109	    {IDT_SW_NTP0_BARSETUP2,	IDT_SW_NTP0_BARLIMIT2,
110	     IDT_SW_NTP0_BARLTBASE2,	IDT_SW_NTP0_BARUTBASE2},
111	    {IDT_SW_NTP0_BARSETUP3,	IDT_SW_NTP0_BARLIMIT3,
112	     IDT_SW_NTP0_BARLTBASE3,	IDT_SW_NTP0_BARUTBASE3},
113	    {IDT_SW_NTP0_BARSETUP4,	IDT_SW_NTP0_BARLIMIT4,
114	     IDT_SW_NTP0_BARLTBASE4,	IDT_SW_NTP0_BARUTBASE4},
115	    {IDT_SW_NTP0_BARSETUP5,	IDT_SW_NTP0_BARLIMIT5,
116	     IDT_SW_NTP0_BARLTBASE5,	IDT_SW_NTP0_BARUTBASE5} } },
117/*1*/	{0},
118/*2*/	{ IDT_SW_NTP2_PCIECMDSTS,	IDT_SW_NTP2_PCIELCTLSTS,
119	  IDT_SW_NTP2_NTCTL,
120	  IDT_SW_SWPORT2CTL,		IDT_SW_SWPORT2STS,
121	  { {IDT_SW_NTP2_BARSETUP0,	IDT_SW_NTP2_BARLIMIT0,
122	     IDT_SW_NTP2_BARLTBASE0,	IDT_SW_NTP2_BARUTBASE0},
123	    {IDT_SW_NTP2_BARSETUP1,	IDT_SW_NTP2_BARLIMIT1,
124	     IDT_SW_NTP2_BARLTBASE1,	IDT_SW_NTP2_BARUTBASE1},
125	    {IDT_SW_NTP2_BARSETUP2,	IDT_SW_NTP2_BARLIMIT2,
126	     IDT_SW_NTP2_BARLTBASE2,	IDT_SW_NTP2_BARUTBASE2},
127	    {IDT_SW_NTP2_BARSETUP3,	IDT_SW_NTP2_BARLIMIT3,
128	     IDT_SW_NTP2_BARLTBASE3,	IDT_SW_NTP2_BARUTBASE3},
129	    {IDT_SW_NTP2_BARSETUP4,	IDT_SW_NTP2_BARLIMIT4,
130	     IDT_SW_NTP2_BARLTBASE4,	IDT_SW_NTP2_BARUTBASE4},
131	    {IDT_SW_NTP2_BARSETUP5,	IDT_SW_NTP2_BARLIMIT5,
132	     IDT_SW_NTP2_BARLTBASE5,	IDT_SW_NTP2_BARUTBASE5} } },
133/*3*/	{0},
134/*4*/	{ IDT_SW_NTP4_PCIECMDSTS,	IDT_SW_NTP4_PCIELCTLSTS,
135	  IDT_SW_NTP4_NTCTL,
136	  IDT_SW_SWPORT4CTL,		IDT_SW_SWPORT4STS,
137	  { {IDT_SW_NTP4_BARSETUP0,	IDT_SW_NTP4_BARLIMIT0,
138	     IDT_SW_NTP4_BARLTBASE0,	IDT_SW_NTP4_BARUTBASE0},
139	    {IDT_SW_NTP4_BARSETUP1,	IDT_SW_NTP4_BARLIMIT1,
140	     IDT_SW_NTP4_BARLTBASE1,	IDT_SW_NTP4_BARUTBASE1},
141	    {IDT_SW_NTP4_BARSETUP2,	IDT_SW_NTP4_BARLIMIT2,
142	     IDT_SW_NTP4_BARLTBASE2,	IDT_SW_NTP4_BARUTBASE2},
143	    {IDT_SW_NTP4_BARSETUP3,	IDT_SW_NTP4_BARLIMIT3,
144	     IDT_SW_NTP4_BARLTBASE3,	IDT_SW_NTP4_BARUTBASE3},
145	    {IDT_SW_NTP4_BARSETUP4,	IDT_SW_NTP4_BARLIMIT4,
146	     IDT_SW_NTP4_BARLTBASE4,	IDT_SW_NTP4_BARUTBASE4},
147	    {IDT_SW_NTP4_BARSETUP5,	IDT_SW_NTP4_BARLIMIT5,
148	     IDT_SW_NTP4_BARLTBASE5,	IDT_SW_NTP4_BARUTBASE5} } },
149/*5*/	{0},
150/*6*/	{ IDT_SW_NTP6_PCIECMDSTS,	IDT_SW_NTP6_PCIELCTLSTS,
151	  IDT_SW_NTP6_NTCTL,
152	  IDT_SW_SWPORT6CTL,		IDT_SW_SWPORT6STS,
153	  { {IDT_SW_NTP6_BARSETUP0,	IDT_SW_NTP6_BARLIMIT0,
154	     IDT_SW_NTP6_BARLTBASE0,	IDT_SW_NTP6_BARUTBASE0},
155	    {IDT_SW_NTP6_BARSETUP1,	IDT_SW_NTP6_BARLIMIT1,
156	     IDT_SW_NTP6_BARLTBASE1,	IDT_SW_NTP6_BARUTBASE1},
157	    {IDT_SW_NTP6_BARSETUP2,	IDT_SW_NTP6_BARLIMIT2,
158	     IDT_SW_NTP6_BARLTBASE2,	IDT_SW_NTP6_BARUTBASE2},
159	    {IDT_SW_NTP6_BARSETUP3,	IDT_SW_NTP6_BARLIMIT3,
160	     IDT_SW_NTP6_BARLTBASE3,	IDT_SW_NTP6_BARUTBASE3},
161	    {IDT_SW_NTP6_BARSETUP4,	IDT_SW_NTP6_BARLIMIT4,
162	     IDT_SW_NTP6_BARLTBASE4,	IDT_SW_NTP6_BARUTBASE4},
163	    {IDT_SW_NTP6_BARSETUP5,	IDT_SW_NTP6_BARLIMIT5,
164	     IDT_SW_NTP6_BARLTBASE5,	IDT_SW_NTP6_BARUTBASE5} } },
165/*7*/	{0},
166/*8*/	{ IDT_SW_NTP8_PCIECMDSTS,	IDT_SW_NTP8_PCIELCTLSTS,
167	  IDT_SW_NTP8_NTCTL,
168	  IDT_SW_SWPORT8CTL,		IDT_SW_SWPORT8STS,
169	  { {IDT_SW_NTP8_BARSETUP0,	IDT_SW_NTP8_BARLIMIT0,
170	     IDT_SW_NTP8_BARLTBASE0,	IDT_SW_NTP8_BARUTBASE0},
171	    {IDT_SW_NTP8_BARSETUP1,	IDT_SW_NTP8_BARLIMIT1,
172	     IDT_SW_NTP8_BARLTBASE1,	IDT_SW_NTP8_BARUTBASE1},
173	    {IDT_SW_NTP8_BARSETUP2,	IDT_SW_NTP8_BARLIMIT2,
174	     IDT_SW_NTP8_BARLTBASE2,	IDT_SW_NTP8_BARUTBASE2},
175	    {IDT_SW_NTP8_BARSETUP3,	IDT_SW_NTP8_BARLIMIT3,
176	     IDT_SW_NTP8_BARLTBASE3,	IDT_SW_NTP8_BARUTBASE3},
177	    {IDT_SW_NTP8_BARSETUP4,	IDT_SW_NTP8_BARLIMIT4,
178	     IDT_SW_NTP8_BARLTBASE4,	IDT_SW_NTP8_BARUTBASE4},
179	    {IDT_SW_NTP8_BARSETUP5,	IDT_SW_NTP8_BARLIMIT5,
180	     IDT_SW_NTP8_BARLTBASE5,	IDT_SW_NTP8_BARUTBASE5} } },
181/*9*/	{0},
182/*10*/	{0},
183/*11*/	{0},
184/*12*/	{ IDT_SW_NTP12_PCIECMDSTS,	IDT_SW_NTP12_PCIELCTLSTS,
185	  IDT_SW_NTP12_NTCTL,
186	  IDT_SW_SWPORT12CTL,		IDT_SW_SWPORT12STS,
187	  { {IDT_SW_NTP12_BARSETUP0,	IDT_SW_NTP12_BARLIMIT0,
188	     IDT_SW_NTP12_BARLTBASE0,	IDT_SW_NTP12_BARUTBASE0},
189	    {IDT_SW_NTP12_BARSETUP1,	IDT_SW_NTP12_BARLIMIT1,
190	     IDT_SW_NTP12_BARLTBASE1,	IDT_SW_NTP12_BARUTBASE1},
191	    {IDT_SW_NTP12_BARSETUP2,	IDT_SW_NTP12_BARLIMIT2,
192	     IDT_SW_NTP12_BARLTBASE2,	IDT_SW_NTP12_BARUTBASE2},
193	    {IDT_SW_NTP12_BARSETUP3,	IDT_SW_NTP12_BARLIMIT3,
194	     IDT_SW_NTP12_BARLTBASE3,	IDT_SW_NTP12_BARUTBASE3},
195	    {IDT_SW_NTP12_BARSETUP4,	IDT_SW_NTP12_BARLIMIT4,
196	     IDT_SW_NTP12_BARLTBASE4,	IDT_SW_NTP12_BARUTBASE4},
197	    {IDT_SW_NTP12_BARSETUP5,	IDT_SW_NTP12_BARLIMIT5,
198	     IDT_SW_NTP12_BARLTBASE5,	IDT_SW_NTP12_BARUTBASE5} } },
199/*13*/	{0},
200/*14*/	{0},
201/*15*/	{0},
202/*16*/	{ IDT_SW_NTP16_PCIECMDSTS,	IDT_SW_NTP16_PCIELCTLSTS,
203	  IDT_SW_NTP16_NTCTL,
204	  IDT_SW_SWPORT16CTL,		IDT_SW_SWPORT16STS,
205	  { {IDT_SW_NTP16_BARSETUP0,	IDT_SW_NTP16_BARLIMIT0,
206	     IDT_SW_NTP16_BARLTBASE0,	IDT_SW_NTP16_BARUTBASE0},
207	    {IDT_SW_NTP16_BARSETUP1,	IDT_SW_NTP16_BARLIMIT1,
208	     IDT_SW_NTP16_BARLTBASE1,	IDT_SW_NTP16_BARUTBASE1},
209	    {IDT_SW_NTP16_BARSETUP2,	IDT_SW_NTP16_BARLIMIT2,
210	     IDT_SW_NTP16_BARLTBASE2,	IDT_SW_NTP16_BARUTBASE2},
211	    {IDT_SW_NTP16_BARSETUP3,	IDT_SW_NTP16_BARLIMIT3,
212	     IDT_SW_NTP16_BARLTBASE3,	IDT_SW_NTP16_BARUTBASE3},
213	    {IDT_SW_NTP16_BARSETUP4,	IDT_SW_NTP16_BARLIMIT4,
214	     IDT_SW_NTP16_BARLTBASE4,	IDT_SW_NTP16_BARUTBASE4},
215	    {IDT_SW_NTP16_BARSETUP5,	IDT_SW_NTP16_BARLIMIT5,
216	     IDT_SW_NTP16_BARLTBASE5,	IDT_SW_NTP16_BARUTBASE5} } },
217/*17*/	{0},
218/*18*/	{0},
219/*19*/	{0},
220/*20*/	{ IDT_SW_NTP20_PCIECMDSTS,	IDT_SW_NTP20_PCIELCTLSTS,
221	  IDT_SW_NTP20_NTCTL,
222	  IDT_SW_SWPORT20CTL,		IDT_SW_SWPORT20STS,
223	  { {IDT_SW_NTP20_BARSETUP0,	IDT_SW_NTP20_BARLIMIT0,
224	     IDT_SW_NTP20_BARLTBASE0,	IDT_SW_NTP20_BARUTBASE0},
225	    {IDT_SW_NTP20_BARSETUP1,	IDT_SW_NTP20_BARLIMIT1,
226	     IDT_SW_NTP20_BARLTBASE1,	IDT_SW_NTP20_BARUTBASE1},
227	    {IDT_SW_NTP20_BARSETUP2,	IDT_SW_NTP20_BARLIMIT2,
228	     IDT_SW_NTP20_BARLTBASE2,	IDT_SW_NTP20_BARUTBASE2},
229	    {IDT_SW_NTP20_BARSETUP3,	IDT_SW_NTP20_BARLIMIT3,
230	     IDT_SW_NTP20_BARLTBASE3,	IDT_SW_NTP20_BARUTBASE3},
231	    {IDT_SW_NTP20_BARSETUP4,	IDT_SW_NTP20_BARLIMIT4,
232	     IDT_SW_NTP20_BARLTBASE4,	IDT_SW_NTP20_BARUTBASE4},
233	    {IDT_SW_NTP20_BARSETUP5,	IDT_SW_NTP20_BARLIMIT5,
234	     IDT_SW_NTP20_BARLTBASE5,	IDT_SW_NTP20_BARUTBASE5} } },
235/*21*/	{0},
236/*22*/	{0},
237/*23*/	{0}
238};
239
240/*
241 * IDT PCIe-switch partitions table with the corresponding control, status
242 * and messages control registers
243 */
244static const struct idt_ntb_part partdata_tbl[IDT_MAX_NR_PARTS] = {
245/*0*/	{ IDT_SW_SWPART0CTL,	IDT_SW_SWPART0STS,
246	  {IDT_SW_SWP0MSGCTL0,	IDT_SW_SWP0MSGCTL1,
247	   IDT_SW_SWP0MSGCTL2,	IDT_SW_SWP0MSGCTL3} },
248/*1*/	{ IDT_SW_SWPART1CTL,	IDT_SW_SWPART1STS,
249	  {IDT_SW_SWP1MSGCTL0,	IDT_SW_SWP1MSGCTL1,
250	   IDT_SW_SWP1MSGCTL2,	IDT_SW_SWP1MSGCTL3} },
251/*2*/	{ IDT_SW_SWPART2CTL,	IDT_SW_SWPART2STS,
252	  {IDT_SW_SWP2MSGCTL0,	IDT_SW_SWP2MSGCTL1,
253	   IDT_SW_SWP2MSGCTL2,	IDT_SW_SWP2MSGCTL3} },
254/*3*/	{ IDT_SW_SWPART3CTL,	IDT_SW_SWPART3STS,
255	  {IDT_SW_SWP3MSGCTL0,	IDT_SW_SWP3MSGCTL1,
256	   IDT_SW_SWP3MSGCTL2,	IDT_SW_SWP3MSGCTL3} },
257/*4*/	{ IDT_SW_SWPART4CTL,	IDT_SW_SWPART4STS,
258	  {IDT_SW_SWP4MSGCTL0,	IDT_SW_SWP4MSGCTL1,
259	   IDT_SW_SWP4MSGCTL2,	IDT_SW_SWP4MSGCTL3} },
260/*5*/	{ IDT_SW_SWPART5CTL,	IDT_SW_SWPART5STS,
261	  {IDT_SW_SWP5MSGCTL0,	IDT_SW_SWP5MSGCTL1,
262	   IDT_SW_SWP5MSGCTL2,	IDT_SW_SWP5MSGCTL3} },
263/*6*/	{ IDT_SW_SWPART6CTL,	IDT_SW_SWPART6STS,
264	  {IDT_SW_SWP6MSGCTL0,	IDT_SW_SWP6MSGCTL1,
265	   IDT_SW_SWP6MSGCTL2,	IDT_SW_SWP6MSGCTL3} },
266/*7*/	{ IDT_SW_SWPART7CTL,	IDT_SW_SWPART7STS,
267	  {IDT_SW_SWP7MSGCTL0,	IDT_SW_SWP7MSGCTL1,
268	   IDT_SW_SWP7MSGCTL2,	IDT_SW_SWP7MSGCTL3} }
269};
270
271/*
272 * DebugFS directory to place the driver debug file
273 */
274static struct dentry *dbgfs_topdir;
275
276/*=============================================================================
277 *                1. IDT PCIe-switch registers IO-functions
278 *
279 *    Beside ordinary configuration space registers IDT PCIe-switch expose
280 * global configuration registers, which are used to determine state of other
281 * device ports as well as being notified of some switch-related events.
282 * Additionally all the configuration space registers of all the IDT
283 * PCIe-switch functions are mapped to the Global Address space, so each
284 * function can determine a configuration of any other PCI-function.
285 *    Functions declared in this chapter are created to encapsulate access
286 * to configuration and global registers, so the driver code just need to
287 * provide IDT NTB hardware descriptor and a register address.
288 *=============================================================================
289 */
290
291/*
292 * idt_nt_write() - PCI configuration space registers write method
293 * @ndev:	IDT NTB hardware driver descriptor
294 * @reg:	Register to write data to
295 * @data:	Value to write to the register
296 *
297 * IDT PCIe-switch registers are all Little endian.
298 */
299static void idt_nt_write(struct idt_ntb_dev *ndev,
300			 const unsigned int reg, const u32 data)
301{
302	/*
303	 * It's obvious bug to request a register exceeding the maximum possible
304	 * value as well as to have it unaligned.
305	 */
306	if (WARN_ON(reg > IDT_REG_PCI_MAX || !IS_ALIGNED(reg, IDT_REG_ALIGN)))
307		return;
308
309	/* Just write the value to the specified register */
310	iowrite32(data, ndev->cfgspc + (ptrdiff_t)reg);
311}
312
313/*
314 * idt_nt_read() - PCI configuration space registers read method
315 * @ndev:	IDT NTB hardware driver descriptor
316 * @reg:	Register to write data to
317 *
318 * IDT PCIe-switch Global configuration registers are all Little endian.
319 *
320 * Return: register value
321 */
322static u32 idt_nt_read(struct idt_ntb_dev *ndev, const unsigned int reg)
323{
324	/*
325	 * It's obvious bug to request a register exceeding the maximum possible
326	 * value as well as to have it unaligned.
327	 */
328	if (WARN_ON(reg > IDT_REG_PCI_MAX || !IS_ALIGNED(reg, IDT_REG_ALIGN)))
329		return ~0;
330
331	/* Just read the value from the specified register */
332	return ioread32(ndev->cfgspc + (ptrdiff_t)reg);
333}
334
335/*
336 * idt_sw_write() - Global registers write method
337 * @ndev:	IDT NTB hardware driver descriptor
338 * @reg:	Register to write data to
339 * @data:	Value to write to the register
340 *
341 * IDT PCIe-switch Global configuration registers are all Little endian.
342 */
343static void idt_sw_write(struct idt_ntb_dev *ndev,
344			 const unsigned int reg, const u32 data)
345{
346	unsigned long irqflags;
347
348	/*
349	 * It's obvious bug to request a register exceeding the maximum possible
350	 * value as well as to have it unaligned.
351	 */
352	if (WARN_ON(reg > IDT_REG_SW_MAX || !IS_ALIGNED(reg, IDT_REG_ALIGN)))
353		return;
354
355	/* Lock GASA registers operations */
356	spin_lock_irqsave(&ndev->gasa_lock, irqflags);
357	/* Set the global register address */
358	iowrite32((u32)reg, ndev->cfgspc + (ptrdiff_t)IDT_NT_GASAADDR);
359	/* Put the new value of the register */
360	iowrite32(data, ndev->cfgspc + (ptrdiff_t)IDT_NT_GASADATA);
361	/* Unlock GASA registers operations */
362	spin_unlock_irqrestore(&ndev->gasa_lock, irqflags);
363}
364
365/*
366 * idt_sw_read() - Global registers read method
367 * @ndev:	IDT NTB hardware driver descriptor
368 * @reg:	Register to write data to
369 *
370 * IDT PCIe-switch Global configuration registers are all Little endian.
371 *
372 * Return: register value
373 */
374static u32 idt_sw_read(struct idt_ntb_dev *ndev, const unsigned int reg)
375{
376	unsigned long irqflags;
377	u32 data;
378
379	/*
380	 * It's obvious bug to request a register exceeding the maximum possible
381	 * value as well as to have it unaligned.
382	 */
383	if (WARN_ON(reg > IDT_REG_SW_MAX || !IS_ALIGNED(reg, IDT_REG_ALIGN)))
384		return ~0;
385
386	/* Lock GASA registers operations */
387	spin_lock_irqsave(&ndev->gasa_lock, irqflags);
388	/* Set the global register address */
389	iowrite32((u32)reg, ndev->cfgspc + (ptrdiff_t)IDT_NT_GASAADDR);
390	/* Get the data of the register (read ops acts as MMIO barrier) */
391	data = ioread32(ndev->cfgspc + (ptrdiff_t)IDT_NT_GASADATA);
392	/* Unlock GASA registers operations */
393	spin_unlock_irqrestore(&ndev->gasa_lock, irqflags);
394
395	return data;
396}
397
398/*
399 * idt_reg_set_bits() - set bits of a passed register
400 * @ndev:	IDT NTB hardware driver descriptor
401 * @reg:	Register to change bits of
402 * @reg_lock:	Register access spin lock
403 * @valid_mask:	Mask of valid bits
404 * @set_bits:	Bitmask to set
405 *
406 * Helper method to check whether a passed bitfield is valid and set
407 * corresponding bits of a register.
408 *
409 * WARNING! Make sure the passed register isn't accessed over plane
410 * idt_nt_write() method (read method is ok to be used concurrently).
411 *
412 * Return: zero on success, negative error on invalid bitmask.
413 */
414static inline int idt_reg_set_bits(struct idt_ntb_dev *ndev, unsigned int reg,
415				   spinlock_t *reg_lock,
416				   u64 valid_mask, u64 set_bits)
417{
418	unsigned long irqflags;
419	u32 data;
420
421	if (set_bits & ~(u64)valid_mask)
422		return -EINVAL;
423
424	/* Lock access to the register unless the change is written back */
425	spin_lock_irqsave(reg_lock, irqflags);
426	data = idt_nt_read(ndev, reg) | (u32)set_bits;
427	idt_nt_write(ndev, reg, data);
428	/* Unlock the register */
429	spin_unlock_irqrestore(reg_lock, irqflags);
430
431	return 0;
432}
433
434/*
435 * idt_reg_clear_bits() - clear bits of a passed register
436 * @ndev:	IDT NTB hardware driver descriptor
437 * @reg:	Register to change bits of
438 * @reg_lock:	Register access spin lock
439 * @set_bits:	Bitmask to clear
440 *
441 * Helper method to check whether a passed bitfield is valid and clear
442 * corresponding bits of a register.
443 *
444 * NOTE! Invalid bits are always considered cleared so it's not an error
445 * to clear them over.
446 *
447 * WARNING! Make sure the passed register isn't accessed over plane
448 * idt_nt_write() method (read method is ok to use concurrently).
449 */
450static inline void idt_reg_clear_bits(struct idt_ntb_dev *ndev,
451				     unsigned int reg, spinlock_t *reg_lock,
452				     u64 clear_bits)
453{
454	unsigned long irqflags;
455	u32 data;
456
457	/* Lock access to the register unless the change is written back */
458	spin_lock_irqsave(reg_lock, irqflags);
459	data = idt_nt_read(ndev, reg) & ~(u32)clear_bits;
460	idt_nt_write(ndev, reg, data);
461	/* Unlock the register */
462	spin_unlock_irqrestore(reg_lock, irqflags);
463}
464
465/*===========================================================================
466 *                           2. Ports operations
467 *
468 *    IDT PCIe-switches can have from 3 up to 8 ports with possible
469 * NT-functions enabled. So all the possible ports need to be scanned looking
470 * for NTB activated. NTB API will have enumerated only the ports with NTB.
471 *===========================================================================
472 */
473
474/*
475 * idt_scan_ports() - scan IDT PCIe-switch ports collecting info in the tables
476 * @ndev:	Pointer to the PCI device descriptor
477 *
478 * Return: zero on success, otherwise a negative error number.
479 */
480static int idt_scan_ports(struct idt_ntb_dev *ndev)
481{
482	unsigned char pidx, port, part;
483	u32 data, portsts, partsts;
484
485	/* Retrieve the local port number */
486	data = idt_nt_read(ndev, IDT_NT_PCIELCAP);
487	ndev->port = GET_FIELD(PCIELCAP_PORTNUM, data);
488
489	/* Retrieve the local partition number */
490	portsts = idt_sw_read(ndev, portdata_tbl[ndev->port].sts);
491	ndev->part = GET_FIELD(SWPORTxSTS_SWPART, portsts);
492
493	/* Initialize port/partition -> index tables with invalid values */
494	memset(ndev->port_idx_map, -EINVAL, sizeof(ndev->port_idx_map));
495	memset(ndev->part_idx_map, -EINVAL, sizeof(ndev->part_idx_map));
496
497	/*
498	 * Walk over all the possible ports checking whether any of them has
499	 * NT-function activated
500	 */
501	ndev->peer_cnt = 0;
502	for (pidx = 0; pidx < ndev->swcfg->port_cnt; pidx++) {
503		port = ndev->swcfg->ports[pidx];
504		/* Skip local port */
505		if (port == ndev->port)
506			continue;
507
508		/* Read the port status register to get it partition */
509		portsts = idt_sw_read(ndev, portdata_tbl[port].sts);
510		part = GET_FIELD(SWPORTxSTS_SWPART, portsts);
511
512		/* Retrieve the partition status */
513		partsts = idt_sw_read(ndev, partdata_tbl[part].sts);
514		/* Check if partition state is active and port has NTB */
515		if (IS_FLD_SET(SWPARTxSTS_STATE, partsts, ACT) &&
516		    (IS_FLD_SET(SWPORTxSTS_MODE, portsts, NT) ||
517		     IS_FLD_SET(SWPORTxSTS_MODE, portsts, USNT) ||
518		     IS_FLD_SET(SWPORTxSTS_MODE, portsts, USNTDMA) ||
519		     IS_FLD_SET(SWPORTxSTS_MODE, portsts, NTDMA))) {
520			/* Save the port and partition numbers */
521			ndev->peers[ndev->peer_cnt].port = port;
522			ndev->peers[ndev->peer_cnt].part = part;
523			/* Fill in the port/partition -> index tables */
524			ndev->port_idx_map[port] = ndev->peer_cnt;
525			ndev->part_idx_map[part] = ndev->peer_cnt;
526			ndev->peer_cnt++;
527		}
528	}
529
530	dev_dbg(&ndev->ntb.pdev->dev, "Local port: %hhu, num of peers: %hhu\n",
531		ndev->port, ndev->peer_cnt);
532
533	/* It's useless to have this driver loaded if there is no any peer */
534	if (ndev->peer_cnt == 0) {
535		dev_warn(&ndev->ntb.pdev->dev, "No active peer found\n");
536		return -ENODEV;
537	}
538
539	return 0;
540}
541
542/*
543 * idt_ntb_port_number() - get the local port number
544 * @ntb:	NTB device context.
545 *
546 * Return: the local port number
547 */
548static int idt_ntb_port_number(struct ntb_dev *ntb)
549{
550	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
551
552	return ndev->port;
553}
554
555/*
556 * idt_ntb_peer_port_count() - get the number of peer ports
557 * @ntb:	NTB device context.
558 *
559 * Return the count of detected peer NT-functions.
560 *
561 * Return: number of peer ports
562 */
563static int idt_ntb_peer_port_count(struct ntb_dev *ntb)
564{
565	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
566
567	return ndev->peer_cnt;
568}
569
570/*
571 * idt_ntb_peer_port_number() - get peer port by given index
572 * @ntb:	NTB device context.
573 * @pidx:	Peer port index.
574 *
575 * Return: peer port or negative error
576 */
577static int idt_ntb_peer_port_number(struct ntb_dev *ntb, int pidx)
578{
579	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
580
581	if (pidx < 0 || ndev->peer_cnt <= pidx)
582		return -EINVAL;
583
584	/* Return the detected NT-function port number */
585	return ndev->peers[pidx].port;
586}
587
588/*
589 * idt_ntb_peer_port_idx() - get peer port index by given port number
590 * @ntb:	NTB device context.
591 * @port:	Peer port number.
592 *
593 * Internal port -> index table is pre-initialized with -EINVAL values,
594 * so we just need to return it value
595 *
596 * Return: peer NT-function port index or negative error
597 */
598static int idt_ntb_peer_port_idx(struct ntb_dev *ntb, int port)
599{
600	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
601
602	if (port < 0 || IDT_MAX_NR_PORTS <= port)
603		return -EINVAL;
604
605	return ndev->port_idx_map[port];
606}
607
608/*===========================================================================
609 *                         3. Link status operations
610 *    There is no any ready-to-use method to have peer ports notified if NTB
611 * link is set up or got down. Instead global signal can be used instead.
612 * In case if any one of ports changes local NTB link state, it sends
613 * global signal and clears corresponding global state bit. Then all the ports
614 * receive a notification of that, so to make client driver being aware of
615 * possible NTB link change.
616 *    Additionally each of active NT-functions is subscribed to PCIe-link
617 * state changes of peer ports.
618 *===========================================================================
619 */
620
621static void idt_ntb_local_link_disable(struct idt_ntb_dev *ndev);
622
623/*
624 * idt_init_link() - Initialize NTB link state notification subsystem
625 * @ndev:	IDT NTB hardware driver descriptor
626 *
627 * Function performs the basic initialization of some global registers
628 * needed to enable IRQ-based notifications of PCIe Link Up/Down and
629 * Global Signal events.
630 * NOTE Since it's not possible to determine when all the NTB peer drivers are
631 * unloaded as well as have those registers accessed concurrently, we must
632 * preinitialize them with the same value and leave it uncleared on local
633 * driver unload.
634 */
635static void idt_init_link(struct idt_ntb_dev *ndev)
636{
637	u32 part_mask, port_mask, se_mask;
638	unsigned char pidx;
639
640	/* Initialize spin locker of Mapping Table access registers */
641	spin_lock_init(&ndev->mtbl_lock);
642
643	/* Walk over all detected peers collecting port and partition masks */
644	port_mask = ~BIT(ndev->port);
645	part_mask = ~BIT(ndev->part);
646	for (pidx = 0; pidx < ndev->peer_cnt; pidx++) {
647		port_mask &= ~BIT(ndev->peers[pidx].port);
648		part_mask &= ~BIT(ndev->peers[pidx].part);
649	}
650
651	/* Clean the Link Up/Down and GLobal Signal status registers */
652	idt_sw_write(ndev, IDT_SW_SELINKUPSTS, (u32)-1);
653	idt_sw_write(ndev, IDT_SW_SELINKDNSTS, (u32)-1);
654	idt_sw_write(ndev, IDT_SW_SEGSIGSTS, (u32)-1);
655
656	/* Unmask NT-activated partitions to receive Global Switch events */
657	idt_sw_write(ndev, IDT_SW_SEPMSK, part_mask);
658
659	/* Enable PCIe Link Up events of NT-activated ports */
660	idt_sw_write(ndev, IDT_SW_SELINKUPMSK, port_mask);
661
662	/* Enable PCIe Link Down events of NT-activated ports */
663	idt_sw_write(ndev, IDT_SW_SELINKDNMSK, port_mask);
664
665	/* Unmask NT-activated partitions to receive Global Signal events */
666	idt_sw_write(ndev, IDT_SW_SEGSIGMSK, part_mask);
667
668	/* Unmask Link Up/Down and Global Switch Events */
669	se_mask = ~(IDT_SEMSK_LINKUP | IDT_SEMSK_LINKDN | IDT_SEMSK_GSIGNAL);
670	idt_sw_write(ndev, IDT_SW_SEMSK, se_mask);
671
672	dev_dbg(&ndev->ntb.pdev->dev, "NTB link status events initialized");
673}
674
675/*
676 * idt_deinit_link() - deinitialize link subsystem
677 * @ndev:	IDT NTB hardware driver descriptor
678 *
679 * Just disable the link back.
680 */
681static void idt_deinit_link(struct idt_ntb_dev *ndev)
682{
683	/* Disable the link */
684	idt_ntb_local_link_disable(ndev);
685
686	dev_dbg(&ndev->ntb.pdev->dev, "NTB link status events deinitialized");
687}
688
689/*
690 * idt_se_isr() - switch events ISR
691 * @ndev:	IDT NTB hardware driver descriptor
692 * @ntint_sts:	NT-function interrupt status
693 *
694 * This driver doesn't support IDT PCIe-switch dynamic reconfigurations,
695 * Failover capability, etc, so switch events are utilized to notify of
696 * PCIe and NTB link events.
697 * The method is called from PCIe ISR bottom-half routine.
698 */
699static void idt_se_isr(struct idt_ntb_dev *ndev, u32 ntint_sts)
700{
701	u32 sests;
702
703	/* Read Switch Events status */
704	sests = idt_sw_read(ndev, IDT_SW_SESTS);
705
706	/* Clean the Link Up/Down and Global Signal status registers */
707	idt_sw_write(ndev, IDT_SW_SELINKUPSTS, (u32)-1);
708	idt_sw_write(ndev, IDT_SW_SELINKDNSTS, (u32)-1);
709	idt_sw_write(ndev, IDT_SW_SEGSIGSTS, (u32)-1);
710
711	/* Clean the corresponding interrupt bit */
712	idt_nt_write(ndev, IDT_NT_NTINTSTS, IDT_NTINTSTS_SEVENT);
713
714	dev_dbg(&ndev->ntb.pdev->dev, "SE IRQ detected %#08x (SESTS %#08x)",
715			  ntint_sts, sests);
716
717	/* Notify the client driver of possible link state change */
718	ntb_link_event(&ndev->ntb);
719}
720
721/*
722 * idt_ntb_local_link_enable() - enable the local NTB link.
723 * @ndev:	IDT NTB hardware driver descriptor
724 *
725 * In order to enable the NTB link we need:
726 * - enable Completion TLPs translation
727 * - initialize mapping table to enable the Request ID translation
728 * - notify peers of NTB link state change
729 */
730static void idt_ntb_local_link_enable(struct idt_ntb_dev *ndev)
731{
732	u32 reqid, mtbldata = 0;
733	unsigned long irqflags;
734
735	/* Enable the ID protection and Completion TLPs translation */
736	idt_nt_write(ndev, IDT_NT_NTCTL, IDT_NTCTL_CPEN);
737
738	/* Retrieve the current Requester ID (Bus:Device:Function) */
739	reqid = idt_nt_read(ndev, IDT_NT_REQIDCAP);
740
741	/*
742	 * Set the corresponding NT Mapping table entry of port partition index
743	 * with the data to perform the Request ID translation
744	 */
745	mtbldata = SET_FIELD(NTMTBLDATA_REQID, 0, reqid) |
746		   SET_FIELD(NTMTBLDATA_PART, 0, ndev->part) |
747		   IDT_NTMTBLDATA_VALID;
748	spin_lock_irqsave(&ndev->mtbl_lock, irqflags);
749	idt_nt_write(ndev, IDT_NT_NTMTBLADDR, ndev->part);
750	idt_nt_write(ndev, IDT_NT_NTMTBLDATA, mtbldata);
751	spin_unlock_irqrestore(&ndev->mtbl_lock, irqflags);
752
753	/* Notify the peers by setting and clearing the global signal bit */
754	idt_nt_write(ndev, IDT_NT_NTGSIGNAL, IDT_NTGSIGNAL_SET);
755	idt_sw_write(ndev, IDT_SW_SEGSIGSTS, (u32)1 << ndev->part);
756}
757
758/*
759 * idt_ntb_local_link_disable() - disable the local NTB link.
760 * @ndev:	IDT NTB hardware driver descriptor
761 *
762 * In order to enable the NTB link we need:
763 * - disable Completion TLPs translation
764 * - clear corresponding mapping table entry
765 * - notify peers of NTB link state change
766 */
767static void idt_ntb_local_link_disable(struct idt_ntb_dev *ndev)
768{
769	unsigned long irqflags;
770
771	/* Disable Completion TLPs translation */
772	idt_nt_write(ndev, IDT_NT_NTCTL, 0);
773
774	/* Clear the corresponding NT Mapping table entry */
775	spin_lock_irqsave(&ndev->mtbl_lock, irqflags);
776	idt_nt_write(ndev, IDT_NT_NTMTBLADDR, ndev->part);
777	idt_nt_write(ndev, IDT_NT_NTMTBLDATA, 0);
778	spin_unlock_irqrestore(&ndev->mtbl_lock, irqflags);
779
780	/* Notify the peers by setting and clearing the global signal bit */
781	idt_nt_write(ndev, IDT_NT_NTGSIGNAL, IDT_NTGSIGNAL_SET);
782	idt_sw_write(ndev, IDT_SW_SEGSIGSTS, (u32)1 << ndev->part);
783}
784
785/*
786 * idt_ntb_local_link_is_up() - test wethter local NTB link is up
787 * @ndev:	IDT NTB hardware driver descriptor
788 *
789 * Local link is up under the following conditions:
790 * - Bus mastering is enabled
791 * - NTCTL has Completion TLPs translation enabled
792 * - Mapping table permits Request TLPs translation
793 * NOTE: We don't need to check PCIe link state since it's obviously
794 * up while we are able to communicate with IDT PCIe-switch
795 *
796 * Return: true if link is up, otherwise false
797 */
798static bool idt_ntb_local_link_is_up(struct idt_ntb_dev *ndev)
799{
800	unsigned long irqflags;
801	u32 data;
802
803	/* Read the local Bus Master Enable status */
804	data = idt_nt_read(ndev, IDT_NT_PCICMDSTS);
805	if (!(data & IDT_PCICMDSTS_BME))
806		return false;
807
808	/* Read the local Completion TLPs translation enable status */
809	data = idt_nt_read(ndev, IDT_NT_NTCTL);
810	if (!(data & IDT_NTCTL_CPEN))
811		return false;
812
813	/* Read Mapping table entry corresponding to the local partition */
814	spin_lock_irqsave(&ndev->mtbl_lock, irqflags);
815	idt_nt_write(ndev, IDT_NT_NTMTBLADDR, ndev->part);
816	data = idt_nt_read(ndev, IDT_NT_NTMTBLDATA);
817	spin_unlock_irqrestore(&ndev->mtbl_lock, irqflags);
818
819	return !!(data & IDT_NTMTBLDATA_VALID);
820}
821
822/*
823 * idt_ntb_peer_link_is_up() - test whether peer NTB link is up
824 * @ndev:	IDT NTB hardware driver descriptor
825 * @pidx:	Peer port index
826 *
827 * Peer link is up under the following conditions:
828 * - PCIe link is up
829 * - Bus mastering is enabled
830 * - NTCTL has Completion TLPs translation enabled
831 * - Mapping table permits Request TLPs translation
832 *
833 * Return: true if link is up, otherwise false
834 */
835static bool idt_ntb_peer_link_is_up(struct idt_ntb_dev *ndev, int pidx)
836{
837	unsigned long irqflags;
838	unsigned char port;
839	u32 data;
840
841	/* Retrieve the device port number */
842	port = ndev->peers[pidx].port;
843
844	/* Check whether PCIe link is up */
845	data = idt_sw_read(ndev, portdata_tbl[port].sts);
846	if (!(data & IDT_SWPORTxSTS_LINKUP))
847		return false;
848
849	/* Check whether bus mastering is enabled on the peer port */
850	data = idt_sw_read(ndev, portdata_tbl[port].pcicmdsts);
851	if (!(data & IDT_PCICMDSTS_BME))
852		return false;
853
854	/* Check if Completion TLPs translation is enabled on the peer port */
855	data = idt_sw_read(ndev, portdata_tbl[port].ntctl);
856	if (!(data & IDT_NTCTL_CPEN))
857		return false;
858
859	/* Read Mapping table entry corresponding to the peer partition */
860	spin_lock_irqsave(&ndev->mtbl_lock, irqflags);
861	idt_nt_write(ndev, IDT_NT_NTMTBLADDR, ndev->peers[pidx].part);
862	data = idt_nt_read(ndev, IDT_NT_NTMTBLDATA);
863	spin_unlock_irqrestore(&ndev->mtbl_lock, irqflags);
864
865	return !!(data & IDT_NTMTBLDATA_VALID);
866}
867
868/*
869 * idt_ntb_link_is_up() - get the current ntb link state (NTB API callback)
870 * @ntb:	NTB device context.
871 * @speed:	OUT - The link speed expressed as PCIe generation number.
872 * @width:	OUT - The link width expressed as the number of PCIe lanes.
873 *
874 * Get the bitfield of NTB link states for all peer ports
875 *
876 * Return: bitfield of indexed ports link state: bit is set/cleared if the
877 *         link is up/down respectively.
878 */
879static u64 idt_ntb_link_is_up(struct ntb_dev *ntb,
880			      enum ntb_speed *speed, enum ntb_width *width)
881{
882	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
883	unsigned char pidx;
884	u64 status;
885	u32 data;
886
887	/* Retrieve the local link speed and width */
888	if (speed != NULL || width != NULL) {
889		data = idt_nt_read(ndev, IDT_NT_PCIELCTLSTS);
890		if (speed != NULL)
891			*speed = GET_FIELD(PCIELCTLSTS_CLS, data);
892		if (width != NULL)
893			*width = GET_FIELD(PCIELCTLSTS_NLW, data);
894	}
895
896	/* If local NTB link isn't up then all the links are considered down */
897	if (!idt_ntb_local_link_is_up(ndev))
898		return 0;
899
900	/* Collect all the peer ports link states into the bitfield */
901	status = 0;
902	for (pidx = 0; pidx < ndev->peer_cnt; pidx++) {
903		if (idt_ntb_peer_link_is_up(ndev, pidx))
904			status |= ((u64)1 << pidx);
905	}
906
907	return status;
908}
909
910/*
911 * idt_ntb_link_enable() - enable local port ntb link (NTB API callback)
912 * @ntb:	NTB device context.
913 * @max_speed:	The maximum link speed expressed as PCIe generation number.
914 * @max_width:	The maximum link width expressed as the number of PCIe lanes.
915 *
916 * Enable just local NTB link. PCIe link parameters are ignored.
917 *
918 * Return: always zero.
919 */
920static int idt_ntb_link_enable(struct ntb_dev *ntb, enum ntb_speed speed,
921			       enum ntb_width width)
922{
923	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
924
925	/* Just enable the local NTB link */
926	idt_ntb_local_link_enable(ndev);
927
928	dev_dbg(&ndev->ntb.pdev->dev, "Local NTB link enabled");
929
930	return 0;
931}
932
933/*
934 * idt_ntb_link_disable() - disable local port ntb link (NTB API callback)
935 * @ntb:	NTB device context.
936 *
937 * Disable just local NTB link.
938 *
939 * Return: always zero.
940 */
941static int idt_ntb_link_disable(struct ntb_dev *ntb)
942{
943	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
944
945	/* Just disable the local NTB link */
946	idt_ntb_local_link_disable(ndev);
947
948	dev_dbg(&ndev->ntb.pdev->dev, "Local NTB link disabled");
949
950	return 0;
951}
952
953/*=============================================================================
954 *                         4. Memory Window operations
955 *
956 *    IDT PCIe-switches have two types of memory windows: MWs with direct
957 * address translation and MWs with LUT based translation. The first type of
958 * MWs is simple map of corresponding BAR address space to a memory space
959 * of specified target port. So it implemets just ont-to-one mapping. Lookup
960 * table in its turn can map one BAR address space to up to 24 different
961 * memory spaces of different ports.
962 *    NT-functions BARs can be turned on to implement either direct or lookup
963 * table based address translations, so:
964 * BAR0 - NT configuration registers space/direct address translation
965 * BAR1 - direct address translation/upper address of BAR0x64
966 * BAR2 - direct address translation/Lookup table with either 12 or 24 entries
967 * BAR3 - direct address translation/upper address of BAR2x64
968 * BAR4 - direct address translation/Lookup table with either 12 or 24 entries
969 * BAR5 - direct address translation/upper address of BAR4x64
970 *    Additionally BAR2 and BAR4 can't have 24-entries LUT enabled at the same
971 * time. Since the BARs setup can be rather complicated this driver implements
972 * a scanning algorithm to have all the possible memory windows configuration
973 * covered.
974 *
975 * NOTE 1 BAR setup must be done before Linux kernel enumerated NT-function
976 * of any port, so this driver would have memory windows configurations fixed.
977 * In this way all initializations must be performed either by platform BIOS
978 * or using EEPROM connected to IDT PCIe-switch master SMBus.
979 *
980 * NOTE 2 This driver expects BAR0 mapping NT-function configuration space.
981 * Easy calculation can give us an upper boundary of 29 possible memory windows
982 * per each NT-function if all the BARs are of 32bit type.
983 *=============================================================================
984 */
985
986/*
987 * idt_get_mw_count() - get memory window count
988 * @mw_type:	Memory window type
989 *
990 * Return: number of memory windows with respect to the BAR type
991 */
992static inline unsigned char idt_get_mw_count(enum idt_mw_type mw_type)
993{
994	switch (mw_type) {
995	case IDT_MW_DIR:
996		return 1;
997	case IDT_MW_LUT12:
998		return 12;
999	case IDT_MW_LUT24:
1000		return 24;
1001	default:
1002		break;
1003	}
1004
1005	return 0;
1006}
1007
1008/*
1009 * idt_get_mw_name() - get memory window name
1010 * @mw_type:	Memory window type
1011 *
1012 * Return: pointer to a string with name
1013 */
1014static inline char *idt_get_mw_name(enum idt_mw_type mw_type)
1015{
1016	switch (mw_type) {
1017	case IDT_MW_DIR:
1018		return "DIR  ";
1019	case IDT_MW_LUT12:
1020		return "LUT12";
1021	case IDT_MW_LUT24:
1022		return "LUT24";
1023	default:
1024		break;
1025	}
1026
1027	return "unknown";
1028}
1029
1030/*
1031 * idt_scan_mws() - scan memory windows of the port
1032 * @ndev:	IDT NTB hardware driver descriptor
1033 * @port:	Port to get number of memory windows for
1034 * @mw_cnt:	Out - number of memory windows
1035 *
1036 * It walks over BAR setup registers of the specified port and determines
1037 * the memory windows parameters if any activated.
1038 *
1039 * Return: array of memory windows
1040 */
1041static struct idt_mw_cfg *idt_scan_mws(struct idt_ntb_dev *ndev, int port,
1042				       unsigned char *mw_cnt)
1043{
1044	struct idt_mw_cfg mws[IDT_MAX_NR_MWS], *ret_mws;
1045	const struct idt_ntb_bar *bars;
1046	enum idt_mw_type mw_type;
1047	unsigned char widx, bidx, en_cnt;
1048	bool bar_64bit = false;
1049	int aprt_size;
1050	u32 data;
1051
1052	/* Retrieve the array of the BARs registers */
1053	bars = portdata_tbl[port].bars;
1054
1055	/* Scan all the BARs belonging to the port */
1056	*mw_cnt = 0;
1057	for (bidx = 0; bidx < IDT_BAR_CNT; bidx += 1 + bar_64bit) {
1058		/* Read BARSETUP register value */
1059		data = idt_sw_read(ndev, bars[bidx].setup);
1060
1061		/* Skip disabled BARs */
1062		if (!(data & IDT_BARSETUP_EN)) {
1063			bar_64bit = false;
1064			continue;
1065		}
1066
1067		/* Skip next BARSETUP if current one has 64bit addressing */
1068		bar_64bit = IS_FLD_SET(BARSETUP_TYPE, data, 64);
1069
1070		/* Skip configuration space mapping BARs */
1071		if (data & IDT_BARSETUP_MODE_CFG)
1072			continue;
1073
1074		/* Retrieve MW type/entries count and aperture size */
1075		mw_type = GET_FIELD(BARSETUP_ATRAN, data);
1076		en_cnt = idt_get_mw_count(mw_type);
1077		aprt_size = (u64)1 << GET_FIELD(BARSETUP_SIZE, data);
1078
1079		/* Save configurations of all available memory windows */
1080		for (widx = 0; widx < en_cnt; widx++, (*mw_cnt)++) {
1081			/*
1082			 * IDT can expose a limited number of MWs, so it's bug
1083			 * to have more than the driver expects
1084			 */
1085			if (*mw_cnt >= IDT_MAX_NR_MWS)
1086				return ERR_PTR(-EINVAL);
1087
1088			/* Save basic MW info */
1089			mws[*mw_cnt].type = mw_type;
1090			mws[*mw_cnt].bar = bidx;
1091			mws[*mw_cnt].idx = widx;
1092			/* It's always DWORD aligned */
1093			mws[*mw_cnt].addr_align = IDT_TRANS_ALIGN;
1094			/* DIR and LUT approachs differently configure MWs */
1095			if (mw_type == IDT_MW_DIR)
1096				mws[*mw_cnt].size_max = aprt_size;
1097			else if (mw_type == IDT_MW_LUT12)
1098				mws[*mw_cnt].size_max = aprt_size / 16;
1099			else
1100				mws[*mw_cnt].size_max = aprt_size / 32;
1101			mws[*mw_cnt].size_align = (mw_type == IDT_MW_DIR) ?
1102				IDT_DIR_SIZE_ALIGN : mws[*mw_cnt].size_max;
1103		}
1104	}
1105
1106	/* Allocate memory for memory window descriptors */
1107	ret_mws = devm_kcalloc(&ndev->ntb.pdev->dev, *mw_cnt, sizeof(*ret_mws),
1108			       GFP_KERNEL);
1109	if (!ret_mws)
1110		return ERR_PTR(-ENOMEM);
1111
1112	/* Copy the info of detected memory windows */
1113	memcpy(ret_mws, mws, (*mw_cnt)*sizeof(*ret_mws));
1114
1115	return ret_mws;
1116}
1117
1118/*
1119 * idt_init_mws() - initialize memory windows subsystem
1120 * @ndev:	IDT NTB hardware driver descriptor
1121 *
1122 * Scan BAR setup registers of local and peer ports to determine the
1123 * outbound and inbound memory windows parameters
1124 *
1125 * Return: zero on success, otherwise a negative error number
1126 */
1127static int idt_init_mws(struct idt_ntb_dev *ndev)
1128{
1129	struct idt_ntb_peer *peer;
1130	unsigned char pidx;
1131
1132	/* Scan memory windows of the local port */
1133	ndev->mws = idt_scan_mws(ndev, ndev->port, &ndev->mw_cnt);
1134	if (IS_ERR(ndev->mws)) {
1135		dev_err(&ndev->ntb.pdev->dev,
1136			"Failed to scan mws of local port %hhu", ndev->port);
1137		return PTR_ERR(ndev->mws);
1138	}
1139
1140	/* Scan memory windows of the peer ports */
1141	for (pidx = 0; pidx < ndev->peer_cnt; pidx++) {
1142		peer = &ndev->peers[pidx];
1143		peer->mws = idt_scan_mws(ndev, peer->port, &peer->mw_cnt);
1144		if (IS_ERR(peer->mws)) {
1145			dev_err(&ndev->ntb.pdev->dev,
1146				"Failed to scan mws of port %hhu", peer->port);
1147			return PTR_ERR(peer->mws);
1148		}
1149	}
1150
1151	/* Initialize spin locker of the LUT registers */
1152	spin_lock_init(&ndev->lut_lock);
1153
1154	dev_dbg(&ndev->ntb.pdev->dev, "Outbound and inbound MWs initialized");
1155
1156	return 0;
1157}
1158
1159/*
1160 * idt_ntb_mw_count() - number of inbound memory windows (NTB API callback)
1161 * @ntb:	NTB device context.
1162 * @pidx:	Port index of peer device.
1163 *
1164 * The value is returned for the specified peer, so generally speaking it can
1165 * be different for different port depending on the IDT PCIe-switch
1166 * initialization.
1167 *
1168 * Return: the number of memory windows.
1169 */
1170static int idt_ntb_mw_count(struct ntb_dev *ntb, int pidx)
1171{
1172	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
1173
1174	if (pidx < 0 || ndev->peer_cnt <= pidx)
1175		return -EINVAL;
1176
1177	return ndev->peers[pidx].mw_cnt;
1178}
1179
1180/*
1181 * idt_ntb_mw_get_align() - inbound memory window parameters (NTB API callback)
1182 * @ntb:	NTB device context.
1183 * @pidx:	Port index of peer device.
1184 * @widx:	Memory window index.
1185 * @addr_align:	OUT - the base alignment for translating the memory window
1186 * @size_align:	OUT - the size alignment for translating the memory window
1187 * @size_max:	OUT - the maximum size of the memory window
1188 *
1189 * The peer memory window parameters have already been determined, so just
1190 * return the corresponding values, which mustn't change within session.
1191 *
1192 * Return: Zero on success, otherwise a negative error number.
1193 */
1194static int idt_ntb_mw_get_align(struct ntb_dev *ntb, int pidx, int widx,
1195				resource_size_t *addr_align,
1196				resource_size_t *size_align,
1197				resource_size_t *size_max)
1198{
1199	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
1200	struct idt_ntb_peer *peer;
1201
1202	if (pidx < 0 || ndev->peer_cnt <= pidx)
1203		return -EINVAL;
1204
1205	peer = &ndev->peers[pidx];
1206
1207	if (widx < 0 || peer->mw_cnt <= widx)
1208		return -EINVAL;
1209
1210	if (addr_align != NULL)
1211		*addr_align = peer->mws[widx].addr_align;
1212
1213	if (size_align != NULL)
1214		*size_align = peer->mws[widx].size_align;
1215
1216	if (size_max != NULL)
1217		*size_max = peer->mws[widx].size_max;
1218
1219	return 0;
1220}
1221
1222/*
1223 * idt_ntb_peer_mw_count() - number of outbound memory windows
1224 *			     (NTB API callback)
1225 * @ntb:	NTB device context.
1226 *
1227 * Outbound memory windows parameters have been determined based on the
1228 * BAR setup registers value, which are mostly constants within one session.
1229 *
1230 * Return: the number of memory windows.
1231 */
1232static int idt_ntb_peer_mw_count(struct ntb_dev *ntb)
1233{
1234	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
1235
1236	return ndev->mw_cnt;
1237}
1238
1239/*
1240 * idt_ntb_peer_mw_get_addr() - get map address of an outbound memory window
1241 *				(NTB API callback)
1242 * @ntb:	NTB device context.
1243 * @widx:	Memory window index (within ntb_peer_mw_count() return value).
1244 * @base:	OUT - the base address of mapping region.
1245 * @size:	OUT - the size of mapping region.
1246 *
1247 * Return just parameters of BAR resources mapping. Size reflects just the size
1248 * of the resource
1249 *
1250 * Return: Zero on success, otherwise a negative error number.
1251 */
1252static int idt_ntb_peer_mw_get_addr(struct ntb_dev *ntb, int widx,
1253				    phys_addr_t *base, resource_size_t *size)
1254{
1255	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
1256
1257	if (widx < 0 || ndev->mw_cnt <= widx)
1258		return -EINVAL;
1259
1260	/* Mapping address is just properly shifted BAR resource start */
1261	if (base != NULL)
1262		*base = pci_resource_start(ntb->pdev, ndev->mws[widx].bar) +
1263			ndev->mws[widx].idx * ndev->mws[widx].size_max;
1264
1265	/* Mapping size has already been calculated at MWs scanning */
1266	if (size != NULL)
1267		*size = ndev->mws[widx].size_max;
1268
1269	return 0;
1270}
1271
1272/*
1273 * idt_ntb_peer_mw_set_trans() - set a translation address of a memory window
1274 *				 (NTB API callback)
1275 * @ntb:	NTB device context.
1276 * @pidx:	Port index of peer device the translation address received from.
1277 * @widx:	Memory window index.
1278 * @addr:	The dma address of the shared memory to access.
1279 * @size:	The size of the shared memory to access.
1280 *
1281 * The Direct address translation and LUT base translation is initialized a
1282 * bit differenet. Although the parameters restriction are now determined by
1283 * the same code.
1284 *
1285 * Return: Zero on success, otherwise an error number.
1286 */
1287static int idt_ntb_peer_mw_set_trans(struct ntb_dev *ntb, int pidx, int widx,
1288				     u64 addr, resource_size_t size)
1289{
1290	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
1291	struct idt_mw_cfg *mw_cfg;
1292	u32 data = 0, lutoff = 0;
1293
1294	if (pidx < 0 || ndev->peer_cnt <= pidx)
1295		return -EINVAL;
1296
1297	if (widx < 0 || ndev->mw_cnt <= widx)
1298		return -EINVAL;
1299
1300	/*
1301	 * Retrieve the memory window config to make sure the passed arguments
1302	 * fit it restrictions
1303	 */
1304	mw_cfg = &ndev->mws[widx];
1305	if (!IS_ALIGNED(addr, mw_cfg->addr_align))
1306		return -EINVAL;
1307	if (!IS_ALIGNED(size, mw_cfg->size_align) || size > mw_cfg->size_max)
1308		return -EINVAL;
1309
1310	/* DIR and LUT based translations are initialized differently */
1311	if (mw_cfg->type == IDT_MW_DIR) {
1312		const struct idt_ntb_bar *bar = &ntdata_tbl.bars[mw_cfg->bar];
1313		u64 limit;
1314		/* Set destination partition of translation */
1315		data = idt_nt_read(ndev, bar->setup);
1316		data = SET_FIELD(BARSETUP_TPART, data, ndev->peers[pidx].part);
1317		idt_nt_write(ndev, bar->setup, data);
1318		/* Set translation base address */
1319		idt_nt_write(ndev, bar->ltbase, (u32)addr);
1320		idt_nt_write(ndev, bar->utbase, (u32)(addr >> 32));
1321		/* Set the custom BAR aperture limit */
1322		limit = pci_bus_address(ntb->pdev, mw_cfg->bar) + size;
1323		idt_nt_write(ndev, bar->limit, (u32)limit);
1324		if (IS_FLD_SET(BARSETUP_TYPE, data, 64))
1325			idt_nt_write(ndev, (bar + 1)->limit, (limit >> 32));
1326	} else {
1327		unsigned long irqflags;
1328		/* Initialize corresponding LUT entry */
1329		lutoff = SET_FIELD(LUTOFFSET_INDEX, 0, mw_cfg->idx) |
1330			 SET_FIELD(LUTOFFSET_BAR, 0, mw_cfg->bar);
1331		data = SET_FIELD(LUTUDATA_PART, 0, ndev->peers[pidx].part) |
1332			IDT_LUTUDATA_VALID;
1333		spin_lock_irqsave(&ndev->lut_lock, irqflags);
1334		idt_nt_write(ndev, IDT_NT_LUTOFFSET, lutoff);
1335		idt_nt_write(ndev, IDT_NT_LUTLDATA, (u32)addr);
1336		idt_nt_write(ndev, IDT_NT_LUTMDATA, (u32)(addr >> 32));
1337		idt_nt_write(ndev, IDT_NT_LUTUDATA, data);
1338		spin_unlock_irqrestore(&ndev->lut_lock, irqflags);
1339		/* Limit address isn't specified since size is fixed for LUT */
1340	}
1341
1342	return 0;
1343}
1344
1345/*
1346 * idt_ntb_peer_mw_clear_trans() - clear the outbound MW translation address
1347 *				   (NTB API callback)
1348 * @ntb:	NTB device context.
1349 * @pidx:	Port index of peer device.
1350 * @widx:	Memory window index.
1351 *
1352 * It effectively disables the translation over the specified outbound MW.
1353 *
1354 * Return: Zero on success, otherwise an error number.
1355 */
1356static int idt_ntb_peer_mw_clear_trans(struct ntb_dev *ntb, int pidx,
1357					int widx)
1358{
1359	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
1360	struct idt_mw_cfg *mw_cfg;
1361
1362	if (pidx < 0 || ndev->peer_cnt <= pidx)
1363		return -EINVAL;
1364
1365	if (widx < 0 || ndev->mw_cnt <= widx)
1366		return -EINVAL;
1367
1368	mw_cfg = &ndev->mws[widx];
1369
1370	/* DIR and LUT based translations are initialized differently */
1371	if (mw_cfg->type == IDT_MW_DIR) {
1372		const struct idt_ntb_bar *bar = &ntdata_tbl.bars[mw_cfg->bar];
1373		u32 data;
1374		/* Read BARSETUP to check BAR type */
1375		data = idt_nt_read(ndev, bar->setup);
1376		/* Disable translation by specifying zero BAR limit */
1377		idt_nt_write(ndev, bar->limit, 0);
1378		if (IS_FLD_SET(BARSETUP_TYPE, data, 64))
1379			idt_nt_write(ndev, (bar + 1)->limit, 0);
1380	} else {
1381		unsigned long irqflags;
1382		u32 lutoff;
1383		/* Clear the corresponding LUT entry up */
1384		lutoff = SET_FIELD(LUTOFFSET_INDEX, 0, mw_cfg->idx) |
1385			 SET_FIELD(LUTOFFSET_BAR, 0, mw_cfg->bar);
1386		spin_lock_irqsave(&ndev->lut_lock, irqflags);
1387		idt_nt_write(ndev, IDT_NT_LUTOFFSET, lutoff);
1388		idt_nt_write(ndev, IDT_NT_LUTLDATA, 0);
1389		idt_nt_write(ndev, IDT_NT_LUTMDATA, 0);
1390		idt_nt_write(ndev, IDT_NT_LUTUDATA, 0);
1391		spin_unlock_irqrestore(&ndev->lut_lock, irqflags);
1392	}
1393
1394	return 0;
1395}
1396
1397/*=============================================================================
1398 *                          5. Doorbell operations
1399 *
1400 *    Doorbell functionality of IDT PCIe-switches is pretty unusual. First of
1401 * all there is global doorbell register which state can be changed by any
1402 * NT-function of the IDT device in accordance with global permissions. These
1403 * permissions configs are not supported by NTB API, so it must be done by
1404 * either BIOS or EEPROM settings. In the same way the state of the global
1405 * doorbell is reflected to the NT-functions local inbound doorbell registers.
1406 * It can lead to situations when client driver sets some peer doorbell bits
1407 * and get them bounced back to local inbound doorbell if permissions are
1408 * granted.
1409 *    Secondly there is just one IRQ vector for Doorbell, Message, Temperature
1410 * and Switch events, so if client driver left any of Doorbell bits set and
1411 * some other event occurred, the driver will be notified of Doorbell event
1412 * again.
1413 *=============================================================================
1414 */
1415
1416/*
1417 * idt_db_isr() - doorbell event ISR
1418 * @ndev:	IDT NTB hardware driver descriptor
1419 * @ntint_sts:	NT-function interrupt status
1420 *
1421 * Doorbell event happans when DBELL bit of NTINTSTS switches from 0 to 1.
1422 * It happens only when unmasked doorbell bits are set to ones on completely
1423 * zeroed doorbell register.
1424 * The method is called from PCIe ISR bottom-half routine.
1425 */
1426static void idt_db_isr(struct idt_ntb_dev *ndev, u32 ntint_sts)
1427{
1428	/*
1429	 * Doorbell IRQ status will be cleaned only when client
1430	 * driver unsets all the doorbell bits.
1431	 */
1432	dev_dbg(&ndev->ntb.pdev->dev, "DB IRQ detected %#08x", ntint_sts);
1433
1434	/* Notify the client driver of possible doorbell state change */
1435	ntb_db_event(&ndev->ntb, 0);
1436}
1437
1438/*
1439 * idt_ntb_db_valid_mask() - get a mask of doorbell bits supported by the ntb
1440 *			     (NTB API callback)
1441 * @ntb:	NTB device context.
1442 *
1443 * IDT PCIe-switches expose just one Doorbell register of DWORD size.
1444 *
1445 * Return: A mask of doorbell bits supported by the ntb.
1446 */
1447static u64 idt_ntb_db_valid_mask(struct ntb_dev *ntb)
1448{
1449	return IDT_DBELL_MASK;
1450}
1451
1452/*
1453 * idt_ntb_db_read() - read the local doorbell register (NTB API callback)
1454 * @ntb:	NTB device context.
1455 *
1456 * There is just on inbound doorbell register of each NT-function, so
1457 * this method return it value.
1458 *
1459 * Return: The bits currently set in the local doorbell register.
1460 */
1461static u64 idt_ntb_db_read(struct ntb_dev *ntb)
1462{
1463	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
1464
1465	return idt_nt_read(ndev, IDT_NT_INDBELLSTS);
1466}
1467
1468/*
1469 * idt_ntb_db_clear() - clear bits in the local doorbell register
1470 *			(NTB API callback)
1471 * @ntb:	NTB device context.
1472 * @db_bits:	Doorbell bits to clear.
1473 *
1474 * Clear bits of inbound doorbell register by writing ones to it.
1475 *
1476 * NOTE! Invalid bits are always considered cleared so it's not an error
1477 * to clear them over.
1478 *
1479 * Return: always zero as success.
1480 */
1481static int idt_ntb_db_clear(struct ntb_dev *ntb, u64 db_bits)
1482{
1483	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
1484
1485	idt_nt_write(ndev, IDT_NT_INDBELLSTS, (u32)db_bits);
1486
1487	return 0;
1488}
1489
1490/*
1491 * idt_ntb_db_read_mask() - read the local doorbell mask (NTB API callback)
1492 * @ntb:	NTB device context.
1493 *
1494 * Each inbound doorbell bit can be masked from generating IRQ by setting
1495 * the corresponding bit in inbound doorbell mask. So this method returns
1496 * the value of the register.
1497 *
1498 * Return: The bits currently set in the local doorbell mask register.
1499 */
1500static u64 idt_ntb_db_read_mask(struct ntb_dev *ntb)
1501{
1502	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
1503
1504	return idt_nt_read(ndev, IDT_NT_INDBELLMSK);
1505}
1506
1507/*
1508 * idt_ntb_db_set_mask() - set bits in the local doorbell mask
1509 *			   (NTB API callback)
1510 * @ntb:	NTB device context.
1511 * @db_bits:	Doorbell mask bits to set.
1512 *
1513 * The inbound doorbell register mask value must be read, then OR'ed with
1514 * passed field and only then set back.
1515 *
1516 * Return: zero on success, negative error if invalid argument passed.
1517 */
1518static int idt_ntb_db_set_mask(struct ntb_dev *ntb, u64 db_bits)
1519{
1520	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
1521
1522	return idt_reg_set_bits(ndev, IDT_NT_INDBELLMSK, &ndev->db_mask_lock,
1523				IDT_DBELL_MASK, db_bits);
1524}
1525
1526/*
1527 * idt_ntb_db_clear_mask() - clear bits in the local doorbell mask
1528 *			     (NTB API callback)
1529 * @ntb:	NTB device context.
1530 * @db_bits:	Doorbell bits to clear.
1531 *
1532 * The method just clears the set bits up in accordance with the passed
1533 * bitfield. IDT PCIe-switch shall generate an interrupt if there hasn't
1534 * been any unmasked bit set before current unmasking. Otherwise IRQ won't
1535 * be generated since there is only one IRQ vector for all doorbells.
1536 *
1537 * Return: always zero as success
1538 */
1539static int idt_ntb_db_clear_mask(struct ntb_dev *ntb, u64 db_bits)
1540{
1541	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
1542
1543	idt_reg_clear_bits(ndev, IDT_NT_INDBELLMSK, &ndev->db_mask_lock,
1544			   db_bits);
1545
1546	return 0;
1547}
1548
1549/*
1550 * idt_ntb_peer_db_set() - set bits in the peer doorbell register
1551 *			   (NTB API callback)
1552 * @ntb:	NTB device context.
1553 * @db_bits:	Doorbell bits to set.
1554 *
1555 * IDT PCIe-switches exposes local outbound doorbell register to change peer
1556 * inbound doorbell register state.
1557 *
1558 * Return: zero on success, negative error if invalid argument passed.
1559 */
1560static int idt_ntb_peer_db_set(struct ntb_dev *ntb, u64 db_bits)
1561{
1562	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
1563
1564	if (db_bits & ~(u64)IDT_DBELL_MASK)
1565		return -EINVAL;
1566
1567	idt_nt_write(ndev, IDT_NT_OUTDBELLSET, (u32)db_bits);
1568	return 0;
1569}
1570
1571/*=============================================================================
1572 *                          6. Messaging operations
1573 *
1574 *    Each NT-function of IDT PCIe-switch has four inbound and four outbound
1575 * message registers. Each outbound message register can be connected to one or
1576 * even more than one peer inbound message registers by setting global
1577 * configurations. Since NTB API permits one-on-one message registers mapping
1578 * only, the driver acts in according with that restriction.
1579 *=============================================================================
1580 */
1581
1582/*
1583 * idt_init_msg() - initialize messaging interface
1584 * @ndev:	IDT NTB hardware driver descriptor
1585 *
1586 * Just initialize the message registers routing tables locker.
1587 */
1588static void idt_init_msg(struct idt_ntb_dev *ndev)
1589{
1590	unsigned char midx;
1591
1592	/* Init the messages routing table lockers */
1593	for (midx = 0; midx < IDT_MSG_CNT; midx++)
1594		spin_lock_init(&ndev->msg_locks[midx]);
1595
1596	dev_dbg(&ndev->ntb.pdev->dev, "NTB Messaging initialized");
1597}
1598
1599/*
1600 * idt_msg_isr() - message event ISR
1601 * @ndev:	IDT NTB hardware driver descriptor
1602 * @ntint_sts:	NT-function interrupt status
1603 *
1604 * Message event happens when MSG bit of NTINTSTS switches from 0 to 1.
1605 * It happens only when unmasked message status bits are set to ones on
1606 * completely zeroed message status register.
1607 * The method is called from PCIe ISR bottom-half routine.
1608 */
1609static void idt_msg_isr(struct idt_ntb_dev *ndev, u32 ntint_sts)
1610{
1611	/*
1612	 * Message IRQ status will be cleaned only when client
1613	 * driver unsets all the message status bits.
1614	 */
1615	dev_dbg(&ndev->ntb.pdev->dev, "Message IRQ detected %#08x", ntint_sts);
1616
1617	/* Notify the client driver of possible message status change */
1618	ntb_msg_event(&ndev->ntb);
1619}
1620
1621/*
1622 * idt_ntb_msg_count() - get the number of message registers (NTB API callback)
1623 * @ntb:	NTB device context.
1624 *
1625 * IDT PCIe-switches support four message registers.
1626 *
1627 * Return: the number of message registers.
1628 */
1629static int idt_ntb_msg_count(struct ntb_dev *ntb)
1630{
1631	return IDT_MSG_CNT;
1632}
1633
1634/*
1635 * idt_ntb_msg_inbits() - get a bitfield of inbound message registers status
1636 *			  (NTB API callback)
1637 * @ntb:	NTB device context.
1638 *
1639 * NT message status register is shared between inbound and outbound message
1640 * registers status
1641 *
1642 * Return: bitfield of inbound message registers.
1643 */
1644static u64 idt_ntb_msg_inbits(struct ntb_dev *ntb)
1645{
1646	return (u64)IDT_INMSG_MASK;
1647}
1648
1649/*
1650 * idt_ntb_msg_outbits() - get a bitfield of outbound message registers status
1651 *			  (NTB API callback)
1652 * @ntb:	NTB device context.
1653 *
1654 * NT message status register is shared between inbound and outbound message
1655 * registers status
1656 *
1657 * Return: bitfield of outbound message registers.
1658 */
1659static u64 idt_ntb_msg_outbits(struct ntb_dev *ntb)
1660{
1661	return (u64)IDT_OUTMSG_MASK;
1662}
1663
1664/*
1665 * idt_ntb_msg_read_sts() - read the message registers status (NTB API callback)
1666 * @ntb:	NTB device context.
1667 *
1668 * IDT PCIe-switches expose message status registers to notify drivers of
1669 * incoming data and failures in case if peer message register isn't freed.
1670 *
1671 * Return: status bits of message registers
1672 */
1673static u64 idt_ntb_msg_read_sts(struct ntb_dev *ntb)
1674{
1675	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
1676
1677	return idt_nt_read(ndev, IDT_NT_MSGSTS);
1678}
1679
1680/*
1681 * idt_ntb_msg_clear_sts() - clear status bits of message registers
1682 *			     (NTB API callback)
1683 * @ntb:	NTB device context.
1684 * @sts_bits:	Status bits to clear.
1685 *
1686 * Clear bits in the status register by writing ones.
1687 *
1688 * NOTE! Invalid bits are always considered cleared so it's not an error
1689 * to clear them over.
1690 *
1691 * Return: always zero as success.
1692 */
1693static int idt_ntb_msg_clear_sts(struct ntb_dev *ntb, u64 sts_bits)
1694{
1695	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
1696
1697	idt_nt_write(ndev, IDT_NT_MSGSTS, sts_bits);
1698
1699	return 0;
1700}
1701
1702/*
1703 * idt_ntb_msg_set_mask() - set mask of message register status bits
1704 *			    (NTB API callback)
1705 * @ntb:	NTB device context.
1706 * @mask_bits:	Mask bits.
1707 *
1708 * Mask the message status bits from raising an IRQ.
1709 *
1710 * Return: zero on success, negative error if invalid argument passed.
1711 */
1712static int idt_ntb_msg_set_mask(struct ntb_dev *ntb, u64 mask_bits)
1713{
1714	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
1715
1716	return idt_reg_set_bits(ndev, IDT_NT_MSGSTSMSK, &ndev->msg_mask_lock,
1717				IDT_MSG_MASK, mask_bits);
1718}
1719
1720/*
1721 * idt_ntb_msg_clear_mask() - clear message registers mask
1722 *			      (NTB API callback)
1723 * @ntb:	NTB device context.
1724 * @mask_bits:	Mask bits.
1725 *
1726 * Clear mask of message status bits IRQs.
1727 *
1728 * Return: always zero as success.
1729 */
1730static int idt_ntb_msg_clear_mask(struct ntb_dev *ntb, u64 mask_bits)
1731{
1732	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
1733
1734	idt_reg_clear_bits(ndev, IDT_NT_MSGSTSMSK, &ndev->msg_mask_lock,
1735			   mask_bits);
1736
1737	return 0;
1738}
1739
1740/*
1741 * idt_ntb_msg_read() - read message register with specified index
1742 *			(NTB API callback)
1743 * @ntb:	NTB device context.
1744 * @pidx:	OUT - Port index of peer device a message retrieved from
1745 * @midx:	Message register index
1746 *
1747 * Read data from the specified message register and source register.
1748 *
1749 * Return: inbound message register value.
1750 */
1751static u32 idt_ntb_msg_read(struct ntb_dev *ntb, int *pidx, int midx)
1752{
1753	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
1754
1755	if (midx < 0 || IDT_MSG_CNT <= midx)
1756		return ~(u32)0;
1757
1758	/* Retrieve source port index of the message */
1759	if (pidx != NULL) {
1760		u32 srcpart;
1761
1762		srcpart = idt_nt_read(ndev, ntdata_tbl.msgs[midx].src);
1763		*pidx = ndev->part_idx_map[srcpart];
1764
1765		/* Sanity check partition index (for initial case) */
1766		if (*pidx == -EINVAL)
1767			*pidx = 0;
1768	}
1769
1770	/* Retrieve data of the corresponding message register */
1771	return idt_nt_read(ndev, ntdata_tbl.msgs[midx].in);
1772}
1773
1774/*
1775 * idt_ntb_peer_msg_write() - write data to the specified message register
1776 *			      (NTB API callback)
1777 * @ntb:	NTB device context.
1778 * @pidx:	Port index of peer device a message being sent to
1779 * @midx:	Message register index
1780 * @msg:	Data to send
1781 *
1782 * Just try to send data to a peer. Message status register should be
1783 * checked by client driver.
1784 *
1785 * Return: zero on success, negative error if invalid argument passed.
1786 */
1787static int idt_ntb_peer_msg_write(struct ntb_dev *ntb, int pidx, int midx,
1788				  u32 msg)
1789{
1790	struct idt_ntb_dev *ndev = to_ndev_ntb(ntb);
1791	unsigned long irqflags;
1792	u32 swpmsgctl = 0;
1793
1794	if (midx < 0 || IDT_MSG_CNT <= midx)
1795		return -EINVAL;
1796
1797	if (pidx < 0 || ndev->peer_cnt <= pidx)
1798		return -EINVAL;
1799
1800	/* Collect the routing information */
1801	swpmsgctl = SET_FIELD(SWPxMSGCTL_REG, 0, midx) |
1802		    SET_FIELD(SWPxMSGCTL_PART, 0, ndev->peers[pidx].part);
1803
1804	/* Lock the messages routing table of the specified register */
1805	spin_lock_irqsave(&ndev->msg_locks[midx], irqflags);
1806	/* Set the route and send the data */
1807	idt_sw_write(ndev, partdata_tbl[ndev->part].msgctl[midx], swpmsgctl);
1808	idt_nt_write(ndev, ntdata_tbl.msgs[midx].out, msg);
1809	/* Unlock the messages routing table */
1810	spin_unlock_irqrestore(&ndev->msg_locks[midx], irqflags);
1811
1812	/* Client driver shall check the status register */
1813	return 0;
1814}
1815
1816/*=============================================================================
1817 *                      7. Temperature sensor operations
1818 *
1819 *    IDT PCIe-switch has an embedded temperature sensor, which can be used to
1820 * check current chip core temperature. Since a workload environment can be
1821 * different on different platforms, an offset and ADC/filter settings can be
1822 * specified. Although the offset configuration is only exposed to the sysfs
1823 * hwmon interface at the moment. The rest of the settings can be adjusted
1824 * for instance by the BIOS/EEPROM firmware.
1825 *=============================================================================
1826 */
1827
1828/*
1829 * idt_get_deg() - convert millidegree Celsius value to just degree
1830 * @mdegC:	IN - millidegree Celsius value
1831 *
1832 * Return: Degree corresponding to the passed millidegree value
1833 */
1834static inline s8 idt_get_deg(long mdegC)
1835{
1836	return mdegC / 1000;
1837}
1838
1839/*
1840 * idt_get_frac() - retrieve 0/0.5 fraction of the millidegree Celsius value
1841 * @mdegC:	IN - millidegree Celsius value
1842 *
1843 * Return: 0/0.5 degree fraction of the passed millidegree value
1844 */
1845static inline u8 idt_get_deg_frac(long mdegC)
1846{
1847	return (mdegC % 1000) >= 500 ? 5 : 0;
1848}
1849
1850/*
1851 * idt_get_temp_fmt() - convert millidegree Celsius value to 0:7:1 format
1852 * @mdegC:	IN - millidegree Celsius value
1853 *
1854 * Return: 0:7:1 format acceptable by the IDT temperature sensor
1855 */
1856static inline u8 idt_temp_get_fmt(long mdegC)
1857{
1858	return (idt_get_deg(mdegC) << 1) | (idt_get_deg_frac(mdegC) ? 1 : 0);
1859}
1860
1861/*
1862 * idt_get_temp_sval() - convert temp sample to signed millidegree Celsius
1863 * @data:	IN - shifted to LSB 8-bits temperature sample
1864 *
1865 * Return: signed millidegree Celsius
1866 */
1867static inline long idt_get_temp_sval(u32 data)
1868{
1869	return ((s8)data / 2) * 1000 + (data & 0x1 ? 500 : 0);
1870}
1871
1872/*
1873 * idt_get_temp_sval() - convert temp sample to unsigned millidegree Celsius
1874 * @data:	IN - shifted to LSB 8-bits temperature sample
1875 *
1876 * Return: unsigned millidegree Celsius
1877 */
1878static inline long idt_get_temp_uval(u32 data)
1879{
1880	return (data / 2) * 1000 + (data & 0x1 ? 500 : 0);
1881}
1882
1883/*
1884 * idt_read_temp() - read temperature from chip sensor
1885 * @ntb:	NTB device context.
1886 * @type:	IN - type of the temperature value to read
1887 * @val:	OUT - integer value of temperature in millidegree Celsius
1888 */
1889static void idt_read_temp(struct idt_ntb_dev *ndev,
1890			  const enum idt_temp_val type, long *val)
1891{
1892	u32 data;
1893
1894	/* Alter the temperature field in accordance with the passed type */
1895	switch (type) {
1896	case IDT_TEMP_CUR:
1897		data = GET_FIELD(TMPSTS_TEMP,
1898				 idt_sw_read(ndev, IDT_SW_TMPSTS));
1899		break;
1900	case IDT_TEMP_LOW:
1901		data = GET_FIELD(TMPSTS_LTEMP,
1902				 idt_sw_read(ndev, IDT_SW_TMPSTS));
1903		break;
1904	case IDT_TEMP_HIGH:
1905		data = GET_FIELD(TMPSTS_HTEMP,
1906				 idt_sw_read(ndev, IDT_SW_TMPSTS));
1907		break;
1908	case IDT_TEMP_OFFSET:
1909		/* This is the only field with signed 0:7:1 format */
1910		data = GET_FIELD(TMPADJ_OFFSET,
1911				 idt_sw_read(ndev, IDT_SW_TMPADJ));
1912		*val = idt_get_temp_sval(data);
1913		return;
1914	default:
1915		data = GET_FIELD(TMPSTS_TEMP,
1916				 idt_sw_read(ndev, IDT_SW_TMPSTS));
1917		break;
1918	}
1919
1920	/* The rest of the fields accept unsigned 0:7:1 format */
1921	*val = idt_get_temp_uval(data);
1922}
1923
1924/*
1925 * idt_write_temp() - write temperature to the chip sensor register
1926 * @ntb:	NTB device context.
1927 * @type:	IN - type of the temperature value to change
1928 * @val:	IN - integer value of temperature in millidegree Celsius
1929 */
1930static void idt_write_temp(struct idt_ntb_dev *ndev,
1931			   const enum idt_temp_val type, const long val)
1932{
1933	unsigned int reg;
1934	u32 data;
1935	u8 fmt;
1936
1937	/* Retrieve the properly formatted temperature value */
1938	fmt = idt_temp_get_fmt(val);
1939
1940	mutex_lock(&ndev->hwmon_mtx);
1941	switch (type) {
1942	case IDT_TEMP_LOW:
1943		reg = IDT_SW_TMPALARM;
1944		data = SET_FIELD(TMPALARM_LTEMP, idt_sw_read(ndev, reg), fmt) &
1945			~IDT_TMPALARM_IRQ_MASK;
1946		break;
1947	case IDT_TEMP_HIGH:
1948		reg = IDT_SW_TMPALARM;
1949		data = SET_FIELD(TMPALARM_HTEMP, idt_sw_read(ndev, reg), fmt) &
1950			~IDT_TMPALARM_IRQ_MASK;
1951		break;
1952	case IDT_TEMP_OFFSET:
1953		reg = IDT_SW_TMPADJ;
1954		data = SET_FIELD(TMPADJ_OFFSET, idt_sw_read(ndev, reg), fmt);
1955		break;
1956	default:
1957		goto inval_spin_unlock;
1958	}
1959
1960	idt_sw_write(ndev, reg, data);
1961
1962inval_spin_unlock:
1963	mutex_unlock(&ndev->hwmon_mtx);
1964}
1965
1966/*
1967 * idt_sysfs_show_temp() - printout corresponding temperature value
1968 * @dev:	Pointer to the NTB device structure
1969 * @da:		Sensor device attribute structure
1970 * @buf:	Buffer to print temperature out
1971 *
1972 * Return: Number of written symbols or negative error
1973 */
1974static ssize_t idt_sysfs_show_temp(struct device *dev,
1975				   struct device_attribute *da, char *buf)
1976{
1977	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
1978	struct idt_ntb_dev *ndev = dev_get_drvdata(dev);
1979	enum idt_temp_val type = attr->index;
1980	long mdeg;
1981
1982	idt_read_temp(ndev, type, &mdeg);
1983	return sprintf(buf, "%ld\n", mdeg);
1984}
1985
1986/*
1987 * idt_sysfs_set_temp() - set corresponding temperature value
1988 * @dev:	Pointer to the NTB device structure
1989 * @da:		Sensor device attribute structure
1990 * @buf:	Buffer to print temperature out
1991 * @count:	Size of the passed buffer
1992 *
1993 * Return: Number of written symbols or negative error
1994 */
1995static ssize_t idt_sysfs_set_temp(struct device *dev,
1996				  struct device_attribute *da, const char *buf,
1997				  size_t count)
1998{
1999	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
2000	struct idt_ntb_dev *ndev = dev_get_drvdata(dev);
2001	enum idt_temp_val type = attr->index;
2002	long mdeg;
2003	int ret;
2004
2005	ret = kstrtol(buf, 10, &mdeg);
2006	if (ret)
2007		return ret;
2008
2009	/* Clamp the passed value in accordance with the type */
2010	if (type == IDT_TEMP_OFFSET)
2011		mdeg = clamp_val(mdeg, IDT_TEMP_MIN_OFFSET,
2012				 IDT_TEMP_MAX_OFFSET);
2013	else
2014		mdeg = clamp_val(mdeg, IDT_TEMP_MIN_MDEG, IDT_TEMP_MAX_MDEG);
2015
2016	idt_write_temp(ndev, type, mdeg);
2017
2018	return count;
2019}
2020
2021/*
2022 * idt_sysfs_reset_hist() - reset temperature history
2023 * @dev:	Pointer to the NTB device structure
2024 * @da:		Sensor device attribute structure
2025 * @buf:	Buffer to print temperature out
2026 * @count:	Size of the passed buffer
2027 *
2028 * Return: Number of written symbols or negative error
2029 */
2030static ssize_t idt_sysfs_reset_hist(struct device *dev,
2031				    struct device_attribute *da,
2032				    const char *buf, size_t count)
2033{
2034	struct idt_ntb_dev *ndev = dev_get_drvdata(dev);
2035
2036	/* Just set the maximal value to the lowest temperature field and
2037	 * minimal value to the highest temperature field
2038	 */
2039	idt_write_temp(ndev, IDT_TEMP_LOW, IDT_TEMP_MAX_MDEG);
2040	idt_write_temp(ndev, IDT_TEMP_HIGH, IDT_TEMP_MIN_MDEG);
2041
2042	return count;
2043}
2044
2045/*
2046 * Hwmon IDT sysfs attributes
2047 */
2048static SENSOR_DEVICE_ATTR(temp1_input, 0444, idt_sysfs_show_temp, NULL,
2049			  IDT_TEMP_CUR);
2050static SENSOR_DEVICE_ATTR(temp1_lowest, 0444, idt_sysfs_show_temp, NULL,
2051			  IDT_TEMP_LOW);
2052static SENSOR_DEVICE_ATTR(temp1_highest, 0444, idt_sysfs_show_temp, NULL,
2053			  IDT_TEMP_HIGH);
2054static SENSOR_DEVICE_ATTR(temp1_offset, 0644, idt_sysfs_show_temp,
2055			  idt_sysfs_set_temp, IDT_TEMP_OFFSET);
2056static DEVICE_ATTR(temp1_reset_history, 0200, NULL, idt_sysfs_reset_hist);
2057
2058/*
2059 * Hwmon IDT sysfs attributes group
2060 */
2061static struct attribute *idt_temp_attrs[] = {
2062	&sensor_dev_attr_temp1_input.dev_attr.attr,
2063	&sensor_dev_attr_temp1_lowest.dev_attr.attr,
2064	&sensor_dev_attr_temp1_highest.dev_attr.attr,
2065	&sensor_dev_attr_temp1_offset.dev_attr.attr,
2066	&dev_attr_temp1_reset_history.attr,
2067	NULL
2068};
2069ATTRIBUTE_GROUPS(idt_temp);
2070
2071/*
2072 * idt_init_temp() - initialize temperature sensor interface
2073 * @ndev:	IDT NTB hardware driver descriptor
2074 *
2075 * Simple sensor initializarion method is responsible for device switching
2076 * on and resource management based hwmon interface registration. Note, that
2077 * since the device is shared we won't disable it on remove, but leave it
2078 * working until the system is powered off.
2079 */
2080static void idt_init_temp(struct idt_ntb_dev *ndev)
2081{
2082	struct device *hwmon;
2083
2084	/* Enable sensor if it hasn't been already */
2085	idt_sw_write(ndev, IDT_SW_TMPCTL, 0x0);
2086
2087	/* Initialize hwmon interface fields */
2088	mutex_init(&ndev->hwmon_mtx);
2089
2090	hwmon = devm_hwmon_device_register_with_groups(&ndev->ntb.pdev->dev,
2091		ndev->swcfg->name, ndev, idt_temp_groups);
2092	if (IS_ERR(hwmon)) {
2093		dev_err(&ndev->ntb.pdev->dev, "Couldn't create hwmon device");
2094		return;
2095	}
2096
2097	dev_dbg(&ndev->ntb.pdev->dev, "Temperature HWmon interface registered");
2098}
2099
2100/*=============================================================================
2101 *                           8. ISRs related operations
2102 *
2103 *    IDT PCIe-switch has strangely developed IRQ system. There is just one
2104 * interrupt vector for doorbell and message registers. So the hardware driver
2105 * can't determine actual source of IRQ if, for example, message event happened
2106 * while any of unmasked doorbell is still set. The similar situation may be if
2107 * switch or temperature sensor events pop up. The difference is that SEVENT
2108 * and TMPSENSOR bits of NT interrupt status register can be cleaned by
2109 * IRQ handler so a next interrupt request won't have false handling of
2110 * corresponding events.
2111 *    The hardware driver has only bottom-half handler of the IRQ, since if any
2112 * of events happened the device won't raise it again before the last one is
2113 * handled by clearing of corresponding NTINTSTS bit.
2114 *=============================================================================
2115 */
2116
2117static irqreturn_t idt_thread_isr(int irq, void *devid);
2118
2119/*
2120 * idt_init_isr() - initialize PCIe interrupt handler
2121 * @ndev:	IDT NTB hardware driver descriptor
2122 *
2123 * Return: zero on success, otherwise a negative error number.
2124 */
2125static int idt_init_isr(struct idt_ntb_dev *ndev)
2126{
2127	struct pci_dev *pdev = ndev->ntb.pdev;
2128	u32 ntint_mask;
2129	int ret;
2130
2131	/* Allocate just one interrupt vector for the ISR */
2132	ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI | PCI_IRQ_LEGACY);
2133	if (ret != 1) {
2134		dev_err(&pdev->dev, "Failed to allocate IRQ vector");
2135		return ret;
2136	}
2137
2138	/* Retrieve the IRQ vector */
2139	ret = pci_irq_vector(pdev, 0);
2140	if (ret < 0) {
2141		dev_err(&pdev->dev, "Failed to get IRQ vector");
2142		goto err_free_vectors;
2143	}
2144
2145	/* Set the IRQ handler */
2146	ret = devm_request_threaded_irq(&pdev->dev, ret, NULL, idt_thread_isr,
2147					IRQF_ONESHOT, NTB_IRQNAME, ndev);
2148	if (ret != 0) {
2149		dev_err(&pdev->dev, "Failed to set MSI IRQ handler, %d", ret);
2150		goto err_free_vectors;
2151	}
2152
2153	/* Unmask Message/Doorbell/SE interrupts */
2154	ntint_mask = idt_nt_read(ndev, IDT_NT_NTINTMSK) & ~IDT_NTINTMSK_ALL;
2155	idt_nt_write(ndev, IDT_NT_NTINTMSK, ntint_mask);
2156
2157	/* From now on the interrupts are enabled */
2158	dev_dbg(&pdev->dev, "NTB interrupts initialized");
2159
2160	return 0;
2161
2162err_free_vectors:
2163	pci_free_irq_vectors(pdev);
2164
2165	return ret;
2166}
2167
2168/*
2169 * idt_deinit_ist() - deinitialize PCIe interrupt handler
2170 * @ndev:	IDT NTB hardware driver descriptor
2171 *
2172 * Disable corresponding interrupts and free allocated IRQ vectors.
2173 */
2174static void idt_deinit_isr(struct idt_ntb_dev *ndev)
2175{
2176	struct pci_dev *pdev = ndev->ntb.pdev;
2177	u32 ntint_mask;
2178
2179	/* Mask interrupts back */
2180	ntint_mask = idt_nt_read(ndev, IDT_NT_NTINTMSK) | IDT_NTINTMSK_ALL;
2181	idt_nt_write(ndev, IDT_NT_NTINTMSK, ntint_mask);
2182
2183	/* Manually free IRQ otherwise PCI free irq vectors will fail */
2184	devm_free_irq(&pdev->dev, pci_irq_vector(pdev, 0), ndev);
2185
2186	/* Free allocated IRQ vectors */
2187	pci_free_irq_vectors(pdev);
2188
2189	dev_dbg(&pdev->dev, "NTB interrupts deinitialized");
2190}
2191
2192/*
2193 * idt_thread_isr() - NT function interrupts handler
2194 * @irq:	IRQ number
2195 * @devid:	Custom buffer
2196 *
2197 * It reads current NT interrupts state register and handles all the event
2198 * it declares.
2199 * The method is bottom-half routine of actual default PCIe IRQ handler.
2200 */
2201static irqreturn_t idt_thread_isr(int irq, void *devid)
2202{
2203	struct idt_ntb_dev *ndev = devid;
2204	bool handled = false;
2205	u32 ntint_sts;
2206
2207	/* Read the NT interrupts status register */
2208	ntint_sts = idt_nt_read(ndev, IDT_NT_NTINTSTS);
2209
2210	/* Handle messaging interrupts */
2211	if (ntint_sts & IDT_NTINTSTS_MSG) {
2212		idt_msg_isr(ndev, ntint_sts);
2213		handled = true;
2214	}
2215
2216	/* Handle doorbell interrupts */
2217	if (ntint_sts & IDT_NTINTSTS_DBELL) {
2218		idt_db_isr(ndev, ntint_sts);
2219		handled = true;
2220	}
2221
2222	/* Handle switch event interrupts */
2223	if (ntint_sts & IDT_NTINTSTS_SEVENT) {
2224		idt_se_isr(ndev, ntint_sts);
2225		handled = true;
2226	}
2227
2228	dev_dbg(&ndev->ntb.pdev->dev, "IDT IRQs 0x%08x handled", ntint_sts);
2229
2230	return handled ? IRQ_HANDLED : IRQ_NONE;
2231}
2232
2233/*===========================================================================
2234 *                     9. NTB hardware driver initialization
2235 *===========================================================================
2236 */
2237
2238/*
2239 * NTB API operations
2240 */
2241static const struct ntb_dev_ops idt_ntb_ops = {
2242	.port_number		= idt_ntb_port_number,
2243	.peer_port_count	= idt_ntb_peer_port_count,
2244	.peer_port_number	= idt_ntb_peer_port_number,
2245	.peer_port_idx		= idt_ntb_peer_port_idx,
2246	.link_is_up		= idt_ntb_link_is_up,
2247	.link_enable		= idt_ntb_link_enable,
2248	.link_disable		= idt_ntb_link_disable,
2249	.mw_count		= idt_ntb_mw_count,
2250	.mw_get_align		= idt_ntb_mw_get_align,
2251	.peer_mw_count		= idt_ntb_peer_mw_count,
2252	.peer_mw_get_addr	= idt_ntb_peer_mw_get_addr,
2253	.peer_mw_set_trans	= idt_ntb_peer_mw_set_trans,
2254	.peer_mw_clear_trans	= idt_ntb_peer_mw_clear_trans,
2255	.db_valid_mask		= idt_ntb_db_valid_mask,
2256	.db_read		= idt_ntb_db_read,
2257	.db_clear		= idt_ntb_db_clear,
2258	.db_read_mask		= idt_ntb_db_read_mask,
2259	.db_set_mask		= idt_ntb_db_set_mask,
2260	.db_clear_mask		= idt_ntb_db_clear_mask,
2261	.peer_db_set		= idt_ntb_peer_db_set,
2262	.msg_count		= idt_ntb_msg_count,
2263	.msg_inbits		= idt_ntb_msg_inbits,
2264	.msg_outbits		= idt_ntb_msg_outbits,
2265	.msg_read_sts		= idt_ntb_msg_read_sts,
2266	.msg_clear_sts		= idt_ntb_msg_clear_sts,
2267	.msg_set_mask		= idt_ntb_msg_set_mask,
2268	.msg_clear_mask		= idt_ntb_msg_clear_mask,
2269	.msg_read		= idt_ntb_msg_read,
2270	.peer_msg_write		= idt_ntb_peer_msg_write
2271};
2272
2273/*
2274 * idt_register_device() - register IDT NTB device
2275 * @ndev:	IDT NTB hardware driver descriptor
2276 *
2277 * Return: zero on success, otherwise a negative error number.
2278 */
2279static int idt_register_device(struct idt_ntb_dev *ndev)
2280{
2281	int ret;
2282
2283	/* Initialize the rest of NTB device structure and register it */
2284	ndev->ntb.ops = &idt_ntb_ops;
2285	ndev->ntb.topo = NTB_TOPO_SWITCH;
2286
2287	ret = ntb_register_device(&ndev->ntb);
2288	if (ret != 0) {
2289		dev_err(&ndev->ntb.pdev->dev, "Failed to register NTB device");
2290		return ret;
2291	}
2292
2293	dev_dbg(&ndev->ntb.pdev->dev, "NTB device successfully registered");
2294
2295	return 0;
2296}
2297
2298/*
2299 * idt_unregister_device() - unregister IDT NTB device
2300 * @ndev:	IDT NTB hardware driver descriptor
2301 */
2302static void idt_unregister_device(struct idt_ntb_dev *ndev)
2303{
2304	/* Just unregister the NTB device */
2305	ntb_unregister_device(&ndev->ntb);
2306
2307	dev_dbg(&ndev->ntb.pdev->dev, "NTB device unregistered");
2308}
2309
2310/*=============================================================================
2311 *                        10. DebugFS node initialization
2312 *=============================================================================
2313 */
2314
2315static ssize_t idt_dbgfs_info_read(struct file *filp, char __user *ubuf,
2316				   size_t count, loff_t *offp);
2317
2318/*
2319 * Driver DebugFS info file operations
2320 */
2321static const struct file_operations idt_dbgfs_info_ops = {
2322	.owner = THIS_MODULE,
2323	.open = simple_open,
2324	.read = idt_dbgfs_info_read
2325};
2326
2327/*
2328 * idt_dbgfs_info_read() - DebugFS read info node callback
2329 * @file:	File node descriptor.
2330 * @ubuf:	User-space buffer to put data to
2331 * @count:	Size of the buffer
2332 * @offp:	Offset within the buffer
2333 */
2334static ssize_t idt_dbgfs_info_read(struct file *filp, char __user *ubuf,
2335				   size_t count, loff_t *offp)
2336{
2337	struct idt_ntb_dev *ndev = filp->private_data;
2338	unsigned char idx, pidx, cnt;
2339	unsigned long irqflags, mdeg;
2340	ssize_t ret = 0, off = 0;
2341	enum ntb_speed speed;
2342	enum ntb_width width;
2343	char *strbuf;
2344	size_t size;
2345	u32 data;
2346
2347	/* Lets limit the buffer size the way the Intel/AMD drivers do */
2348	size = min_t(size_t, count, 0x1000U);
2349
2350	/* Allocate the memory for the buffer */
2351	strbuf = kmalloc(size, GFP_KERNEL);
2352	if (strbuf == NULL)
2353		return -ENOMEM;
2354
2355	/* Put the data into the string buffer */
2356	off += scnprintf(strbuf + off, size - off,
2357		"\n\t\tIDT NTB device Information:\n\n");
2358
2359	/* General local device configurations */
2360	off += scnprintf(strbuf + off, size - off,
2361		"Local Port %hhu, Partition %hhu\n", ndev->port, ndev->part);
2362
2363	/* Peer ports information */
2364	off += scnprintf(strbuf + off, size - off, "Peers:\n");
2365	for (idx = 0; idx < ndev->peer_cnt; idx++) {
2366		off += scnprintf(strbuf + off, size - off,
2367			"\t%hhu. Port %hhu, Partition %hhu\n",
2368			idx, ndev->peers[idx].port, ndev->peers[idx].part);
2369	}
2370
2371	/* Links status */
2372	data = idt_ntb_link_is_up(&ndev->ntb, &speed, &width);
2373	off += scnprintf(strbuf + off, size - off,
2374		"NTB link status\t- 0x%08x, ", data);
2375	off += scnprintf(strbuf + off, size - off, "PCIe Gen %d x%d lanes\n",
2376		speed, width);
2377
2378	/* Mapping table entries */
2379	off += scnprintf(strbuf + off, size - off, "NTB Mapping Table:\n");
2380	for (idx = 0; idx < IDT_MTBL_ENTRY_CNT; idx++) {
2381		spin_lock_irqsave(&ndev->mtbl_lock, irqflags);
2382		idt_nt_write(ndev, IDT_NT_NTMTBLADDR, idx);
2383		data = idt_nt_read(ndev, IDT_NT_NTMTBLDATA);
2384		spin_unlock_irqrestore(&ndev->mtbl_lock, irqflags);
2385
2386		/* Print valid entries only */
2387		if (data & IDT_NTMTBLDATA_VALID) {
2388			off += scnprintf(strbuf + off, size - off,
2389				"\t%hhu. Partition %d, Requester ID 0x%04x\n",
2390				idx, GET_FIELD(NTMTBLDATA_PART, data),
2391				GET_FIELD(NTMTBLDATA_REQID, data));
2392		}
2393	}
2394	off += scnprintf(strbuf + off, size - off, "\n");
2395
2396	/* Outbound memory windows information */
2397	off += scnprintf(strbuf + off, size - off,
2398		"Outbound Memory Windows:\n");
2399	for (idx = 0; idx < ndev->mw_cnt; idx += cnt) {
2400		data = ndev->mws[idx].type;
2401		cnt = idt_get_mw_count(data);
2402
2403		/* Print Memory Window information */
2404		if (data == IDT_MW_DIR)
2405			off += scnprintf(strbuf + off, size - off,
2406				"\t%hhu.\t", idx);
2407		else
2408			off += scnprintf(strbuf + off, size - off,
2409				"\t%hhu-%hhu.\t", idx, idx + cnt - 1);
2410
2411		off += scnprintf(strbuf + off, size - off, "%s BAR%hhu, ",
2412			idt_get_mw_name(data), ndev->mws[idx].bar);
2413
2414		off += scnprintf(strbuf + off, size - off,
2415			"Address align 0x%08llx, ", ndev->mws[idx].addr_align);
2416
2417		off += scnprintf(strbuf + off, size - off,
2418			"Size align 0x%08llx, Size max %llu\n",
2419			ndev->mws[idx].size_align, ndev->mws[idx].size_max);
2420	}
2421
2422	/* Inbound memory windows information */
2423	for (pidx = 0; pidx < ndev->peer_cnt; pidx++) {
2424		off += scnprintf(strbuf + off, size - off,
2425			"Inbound Memory Windows for peer %hhu (Port %hhu):\n",
2426			pidx, ndev->peers[pidx].port);
2427
2428		/* Print Memory Windows information */
2429		for (idx = 0; idx < ndev->peers[pidx].mw_cnt; idx += cnt) {
2430			data = ndev->peers[pidx].mws[idx].type;
2431			cnt = idt_get_mw_count(data);
2432
2433			if (data == IDT_MW_DIR)
2434				off += scnprintf(strbuf + off, size - off,
2435					"\t%hhu.\t", idx);
2436			else
2437				off += scnprintf(strbuf + off, size - off,
2438					"\t%hhu-%hhu.\t", idx, idx + cnt - 1);
2439
2440			off += scnprintf(strbuf + off, size - off,
2441				"%s BAR%hhu, ", idt_get_mw_name(data),
2442				ndev->peers[pidx].mws[idx].bar);
2443
2444			off += scnprintf(strbuf + off, size - off,
2445				"Address align 0x%08llx, ",
2446				ndev->peers[pidx].mws[idx].addr_align);
2447
2448			off += scnprintf(strbuf + off, size - off,
2449				"Size align 0x%08llx, Size max %llu\n",
2450				ndev->peers[pidx].mws[idx].size_align,
2451				ndev->peers[pidx].mws[idx].size_max);
2452		}
2453	}
2454	off += scnprintf(strbuf + off, size - off, "\n");
2455
2456	/* Doorbell information */
2457	data = idt_sw_read(ndev, IDT_SW_GDBELLSTS);
2458	off += scnprintf(strbuf + off, size - off,
2459		 "Global Doorbell state\t- 0x%08x\n", data);
2460	data = idt_ntb_db_read(&ndev->ntb);
2461	off += scnprintf(strbuf + off, size - off,
2462		 "Local  Doorbell state\t- 0x%08x\n", data);
2463	data = idt_nt_read(ndev, IDT_NT_INDBELLMSK);
2464	off += scnprintf(strbuf + off, size - off,
2465		 "Local  Doorbell mask\t- 0x%08x\n", data);
2466	off += scnprintf(strbuf + off, size - off, "\n");
2467
2468	/* Messaging information */
2469	off += scnprintf(strbuf + off, size - off,
2470		 "Message event valid\t- 0x%08x\n", IDT_MSG_MASK);
2471	data = idt_ntb_msg_read_sts(&ndev->ntb);
2472	off += scnprintf(strbuf + off, size - off,
2473		 "Message event status\t- 0x%08x\n", data);
2474	data = idt_nt_read(ndev, IDT_NT_MSGSTSMSK);
2475	off += scnprintf(strbuf + off, size - off,
2476		 "Message event mask\t- 0x%08x\n", data);
2477	off += scnprintf(strbuf + off, size - off,
2478		 "Message data:\n");
2479	for (idx = 0; idx < IDT_MSG_CNT; idx++) {
2480		int src;
2481		data = idt_ntb_msg_read(&ndev->ntb, &src, idx);
2482		off += scnprintf(strbuf + off, size - off,
2483			"\t%hhu. 0x%08x from peer %hhu (Port %hhu)\n",
2484			idx, data, src, ndev->peers[src].port);
2485	}
2486	off += scnprintf(strbuf + off, size - off, "\n");
2487
2488	/* Current temperature */
2489	idt_read_temp(ndev, IDT_TEMP_CUR, &mdeg);
2490	off += scnprintf(strbuf + off, size - off,
2491		"Switch temperature\t\t- %hhd.%hhuC\n",
2492		idt_get_deg(mdeg), idt_get_deg_frac(mdeg));
2493
2494	/* Copy the buffer to the User Space */
2495	ret = simple_read_from_buffer(ubuf, count, offp, strbuf, off);
2496	kfree(strbuf);
2497
2498	return ret;
2499}
2500
2501/*
2502 * idt_init_dbgfs() - initialize DebugFS node
2503 * @ndev:	IDT NTB hardware driver descriptor
2504 *
2505 * Return: zero on success, otherwise a negative error number.
2506 */
2507static int idt_init_dbgfs(struct idt_ntb_dev *ndev)
2508{
2509	char devname[64];
2510
2511	/* If the top directory is not created then do nothing */
2512	if (IS_ERR_OR_NULL(dbgfs_topdir)) {
2513		dev_info(&ndev->ntb.pdev->dev, "Top DebugFS directory absent");
2514		return PTR_ERR(dbgfs_topdir);
2515	}
2516
2517	/* Create the info file node */
2518	snprintf(devname, 64, "info:%s", pci_name(ndev->ntb.pdev));
2519	ndev->dbgfs_info = debugfs_create_file(devname, 0400, dbgfs_topdir,
2520		ndev, &idt_dbgfs_info_ops);
2521	if (IS_ERR(ndev->dbgfs_info)) {
2522		dev_dbg(&ndev->ntb.pdev->dev, "Failed to create DebugFS node");
2523		return PTR_ERR(ndev->dbgfs_info);
2524	}
2525
2526	dev_dbg(&ndev->ntb.pdev->dev, "NTB device DebugFS node created");
2527
2528	return 0;
2529}
2530
2531/*
2532 * idt_deinit_dbgfs() - deinitialize DebugFS node
2533 * @ndev:	IDT NTB hardware driver descriptor
2534 *
2535 * Just discard the info node from DebugFS
2536 */
2537static void idt_deinit_dbgfs(struct idt_ntb_dev *ndev)
2538{
2539	debugfs_remove(ndev->dbgfs_info);
2540
2541	dev_dbg(&ndev->ntb.pdev->dev, "NTB device DebugFS node discarded");
2542}
2543
2544/*=============================================================================
2545 *                     11. Basic PCIe device initialization
2546 *=============================================================================
2547 */
2548
2549/*
2550 * idt_check_setup() - Check whether the IDT PCIe-swtich is properly
2551 *		       pre-initialized
2552 * @pdev:	Pointer to the PCI device descriptor
2553 *
2554 * Return: zero on success, otherwise a negative error number.
2555 */
2556static int idt_check_setup(struct pci_dev *pdev)
2557{
2558	u32 data;
2559	int ret;
2560
2561	/* Read the BARSETUP0 */
2562	ret = pci_read_config_dword(pdev, IDT_NT_BARSETUP0, &data);
2563	if (ret != 0) {
2564		dev_err(&pdev->dev,
2565			"Failed to read BARSETUP0 config register");
2566		return ret;
2567	}
2568
2569	/* Check whether the BAR0 register is enabled to be of config space */
2570	if (!(data & IDT_BARSETUP_EN) || !(data & IDT_BARSETUP_MODE_CFG)) {
2571		dev_err(&pdev->dev, "BAR0 doesn't map config space");
2572		return -EINVAL;
2573	}
2574
2575	/* Configuration space BAR0 must have certain size */
2576	if ((data & IDT_BARSETUP_SIZE_MASK) != IDT_BARSETUP_SIZE_CFG) {
2577		dev_err(&pdev->dev, "Invalid size of config space");
2578		return -EINVAL;
2579	}
2580
2581	dev_dbg(&pdev->dev, "NTB device pre-initialized correctly");
2582
2583	return 0;
2584}
2585
2586/*
2587 * Create the IDT PCIe-switch driver descriptor
2588 * @pdev:	Pointer to the PCI device descriptor
2589 * @id:		IDT PCIe-device configuration
2590 *
2591 * It just allocates a memory for IDT PCIe-switch device structure and
2592 * initializes some commonly used fields.
2593 *
2594 * No need of release method, since managed device resource is used for
2595 * memory allocation.
2596 *
2597 * Return: pointer to the descriptor, otherwise a negative error number.
2598 */
2599static struct idt_ntb_dev *idt_create_dev(struct pci_dev *pdev,
2600					  const struct pci_device_id *id)
2601{
2602	struct idt_ntb_dev *ndev;
2603
2604	/* Allocate memory for the IDT PCIe-device descriptor */
2605	ndev = devm_kzalloc(&pdev->dev, sizeof(*ndev), GFP_KERNEL);
2606	if (!ndev) {
2607		dev_err(&pdev->dev, "Memory allocation failed for descriptor");
2608		return ERR_PTR(-ENOMEM);
2609	}
2610
2611	/* Save the IDT PCIe-switch ports configuration */
2612	ndev->swcfg = (struct idt_89hpes_cfg *)id->driver_data;
2613	/* Save the PCI-device pointer inside the NTB device structure */
2614	ndev->ntb.pdev = pdev;
2615
2616	/* Initialize spin locker of Doorbell, Message and GASA registers */
2617	spin_lock_init(&ndev->db_mask_lock);
2618	spin_lock_init(&ndev->msg_mask_lock);
2619	spin_lock_init(&ndev->gasa_lock);
2620
2621	dev_info(&pdev->dev, "IDT %s discovered", ndev->swcfg->name);
2622
2623	dev_dbg(&pdev->dev, "NTB device descriptor created");
2624
2625	return ndev;
2626}
2627
2628/*
2629 * idt_init_pci() - initialize the basic PCI-related subsystem
2630 * @ndev:	Pointer to the IDT PCIe-switch driver descriptor
2631 *
2632 * Managed device resources will be freed automatically in case of failure or
2633 * driver detachment.
2634 *
2635 * Return: zero on success, otherwise negative error number.
2636 */
2637static int idt_init_pci(struct idt_ntb_dev *ndev)
2638{
2639	struct pci_dev *pdev = ndev->ntb.pdev;
2640	int ret;
2641
2642	/* Initialize the bit mask of PCI/NTB DMA */
2643	ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(64));
2644	if (ret != 0) {
2645		ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
2646		if (ret != 0) {
2647			dev_err(&pdev->dev, "Failed to set DMA bit mask\n");
2648			return ret;
2649		}
2650		dev_warn(&pdev->dev, "Cannot set DMA highmem bit mask\n");
2651	}
2652	ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64));
2653	if (ret != 0) {
2654		ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
2655		if (ret != 0) {
2656			dev_err(&pdev->dev,
2657				"Failed to set consistent DMA bit mask\n");
2658			return ret;
2659		}
2660		dev_warn(&pdev->dev,
2661			"Cannot set consistent DMA highmem bit mask\n");
2662	}
2663
2664	/*
2665	 * Enable the device advanced error reporting. It's not critical to
2666	 * have AER disabled in the kernel.
2667	 */
2668	ret = pci_enable_pcie_error_reporting(pdev);
2669	if (ret != 0)
2670		dev_warn(&pdev->dev, "PCIe AER capability disabled\n");
2671	else /* Cleanup nonfatal error status before getting to init */
2672		pci_aer_clear_nonfatal_status(pdev);
2673
2674	/* First enable the PCI device */
2675	ret = pcim_enable_device(pdev);
2676	if (ret != 0) {
2677		dev_err(&pdev->dev, "Failed to enable PCIe device\n");
2678		goto err_disable_aer;
2679	}
2680
2681	/*
2682	 * Enable the bus mastering, which effectively enables MSI IRQs and
2683	 * Request TLPs translation
2684	 */
2685	pci_set_master(pdev);
2686
2687	/* Request all BARs resources and map BAR0 only */
2688	ret = pcim_iomap_regions_request_all(pdev, 1, NTB_NAME);
2689	if (ret != 0) {
2690		dev_err(&pdev->dev, "Failed to request resources\n");
2691		goto err_clear_master;
2692	}
2693
2694	/* Retrieve virtual address of BAR0 - PCI configuration space */
2695	ndev->cfgspc = pcim_iomap_table(pdev)[0];
2696
2697	/* Put the IDT driver data pointer to the PCI-device private pointer */
2698	pci_set_drvdata(pdev, ndev);
2699
2700	dev_dbg(&pdev->dev, "NT-function PCIe interface initialized");
2701
2702	return 0;
2703
2704err_clear_master:
2705	pci_clear_master(pdev);
2706err_disable_aer:
2707	(void)pci_disable_pcie_error_reporting(pdev);
2708
2709	return ret;
2710}
2711
2712/*
2713 * idt_deinit_pci() - deinitialize the basic PCI-related subsystem
2714 * @ndev:	Pointer to the IDT PCIe-switch driver descriptor
2715 *
2716 * Managed resources will be freed on the driver detachment
2717 */
2718static void idt_deinit_pci(struct idt_ntb_dev *ndev)
2719{
2720	struct pci_dev *pdev = ndev->ntb.pdev;
2721
2722	/* Clean up the PCI-device private data pointer */
2723	pci_set_drvdata(pdev, NULL);
2724
2725	/* Clear the bus master disabling the Request TLPs translation */
2726	pci_clear_master(pdev);
2727
2728	/* Disable the AER capability */
2729	(void)pci_disable_pcie_error_reporting(pdev);
2730
2731	dev_dbg(&pdev->dev, "NT-function PCIe interface cleared");
2732}
2733
2734/*===========================================================================
2735 *                       12. PCI bus callback functions
2736 *===========================================================================
2737 */
2738
2739/*
2740 * idt_pci_probe() - PCI device probe callback
2741 * @pdev:	Pointer to PCI device structure
2742 * @id:		PCIe device custom descriptor
2743 *
2744 * Return: zero on success, otherwise negative error number
2745 */
2746static int idt_pci_probe(struct pci_dev *pdev,
2747			 const struct pci_device_id *id)
2748{
2749	struct idt_ntb_dev *ndev;
2750	int ret;
2751
2752	/* Check whether IDT PCIe-switch is properly pre-initialized */
2753	ret = idt_check_setup(pdev);
2754	if (ret != 0)
2755		return ret;
2756
2757	/* Allocate the memory for IDT NTB device data */
2758	ndev = idt_create_dev(pdev, id);
2759	if (IS_ERR_OR_NULL(ndev))
2760		return PTR_ERR(ndev);
2761
2762	/* Initialize the basic PCI subsystem of the device */
2763	ret = idt_init_pci(ndev);
2764	if (ret != 0)
2765		return ret;
2766
2767	/* Scan ports of the IDT PCIe-switch */
2768	(void)idt_scan_ports(ndev);
2769
2770	/* Initialize NTB link events subsystem */
2771	idt_init_link(ndev);
2772
2773	/* Initialize MWs subsystem */
2774	ret = idt_init_mws(ndev);
2775	if (ret != 0)
2776		goto err_deinit_link;
2777
2778	/* Initialize Messaging subsystem */
2779	idt_init_msg(ndev);
2780
2781	/* Initialize hwmon interface */
2782	idt_init_temp(ndev);
2783
2784	/* Initialize IDT interrupts handler */
2785	ret = idt_init_isr(ndev);
2786	if (ret != 0)
2787		goto err_deinit_link;
2788
2789	/* Register IDT NTB devices on the NTB bus */
2790	ret = idt_register_device(ndev);
2791	if (ret != 0)
2792		goto err_deinit_isr;
2793
2794	/* Initialize DebugFS info node */
2795	(void)idt_init_dbgfs(ndev);
2796
2797	/* IDT PCIe-switch NTB driver is finally initialized */
2798	dev_info(&pdev->dev, "IDT NTB device is ready");
2799
2800	/* May the force be with us... */
2801	return 0;
2802
2803err_deinit_isr:
2804	idt_deinit_isr(ndev);
2805err_deinit_link:
2806	idt_deinit_link(ndev);
2807	idt_deinit_pci(ndev);
2808
2809	return ret;
2810}
2811
2812/*
2813 * idt_pci_probe() - PCI device remove callback
2814 * @pdev:	Pointer to PCI device structure
2815 */
2816static void idt_pci_remove(struct pci_dev *pdev)
2817{
2818	struct idt_ntb_dev *ndev = pci_get_drvdata(pdev);
2819
2820	/* Deinit the DebugFS node */
2821	idt_deinit_dbgfs(ndev);
2822
2823	/* Unregister NTB device */
2824	idt_unregister_device(ndev);
2825
2826	/* Stop the interrupts handling */
2827	idt_deinit_isr(ndev);
2828
2829	/* Deinitialize link event subsystem */
2830	idt_deinit_link(ndev);
2831
2832	/* Deinit basic PCI subsystem */
2833	idt_deinit_pci(ndev);
2834
2835	/* IDT PCIe-switch NTB driver is finally initialized */
2836	dev_info(&pdev->dev, "IDT NTB device is removed");
2837
2838	/* Sayonara... */
2839}
2840
2841/*
2842 * IDT PCIe-switch models ports configuration structures
2843 */
2844static const struct idt_89hpes_cfg idt_89hpes24nt6ag2_config = {
2845	.name = "89HPES24NT6AG2",
2846	.port_cnt = 6, .ports = {0, 2, 4, 6, 8, 12}
2847};
2848static const struct idt_89hpes_cfg idt_89hpes32nt8ag2_config = {
2849	.name = "89HPES32NT8AG2",
2850	.port_cnt = 8, .ports = {0, 2, 4, 6, 8, 12, 16, 20}
2851};
2852static const struct idt_89hpes_cfg idt_89hpes32nt8bg2_config = {
2853	.name = "89HPES32NT8BG2",
2854	.port_cnt = 8, .ports = {0, 2, 4, 6, 8, 12, 16, 20}
2855};
2856static const struct idt_89hpes_cfg idt_89hpes12nt12g2_config = {
2857	.name = "89HPES12NT12G2",
2858	.port_cnt = 3, .ports = {0, 8, 16}
2859};
2860static const struct idt_89hpes_cfg idt_89hpes16nt16g2_config = {
2861	.name = "89HPES16NT16G2",
2862	.port_cnt = 4, .ports = {0, 8, 12, 16}
2863};
2864static const struct idt_89hpes_cfg idt_89hpes24nt24g2_config = {
2865	.name = "89HPES24NT24G2",
2866	.port_cnt = 8, .ports = {0, 2, 4, 6, 8, 12, 16, 20}
2867};
2868static const struct idt_89hpes_cfg idt_89hpes32nt24ag2_config = {
2869	.name = "89HPES32NT24AG2",
2870	.port_cnt = 8, .ports = {0, 2, 4, 6, 8, 12, 16, 20}
2871};
2872static const struct idt_89hpes_cfg idt_89hpes32nt24bg2_config = {
2873	.name = "89HPES32NT24BG2",
2874	.port_cnt = 8, .ports = {0, 2, 4, 6, 8, 12, 16, 20}
2875};
2876
2877/*
2878 * PCI-ids table of the supported IDT PCIe-switch devices
2879 */
2880static const struct pci_device_id idt_pci_tbl[] = {
2881	{IDT_PCI_DEVICE_IDS(89HPES24NT6AG2,  idt_89hpes24nt6ag2_config)},
2882	{IDT_PCI_DEVICE_IDS(89HPES32NT8AG2,  idt_89hpes32nt8ag2_config)},
2883	{IDT_PCI_DEVICE_IDS(89HPES32NT8BG2,  idt_89hpes32nt8bg2_config)},
2884	{IDT_PCI_DEVICE_IDS(89HPES12NT12G2,  idt_89hpes12nt12g2_config)},
2885	{IDT_PCI_DEVICE_IDS(89HPES16NT16G2,  idt_89hpes16nt16g2_config)},
2886	{IDT_PCI_DEVICE_IDS(89HPES24NT24G2,  idt_89hpes24nt24g2_config)},
2887	{IDT_PCI_DEVICE_IDS(89HPES32NT24AG2, idt_89hpes32nt24ag2_config)},
2888	{IDT_PCI_DEVICE_IDS(89HPES32NT24BG2, idt_89hpes32nt24bg2_config)},
2889	{0}
2890};
2891MODULE_DEVICE_TABLE(pci, idt_pci_tbl);
2892
2893/*
2894 * IDT PCIe-switch NT-function device driver structure definition
2895 */
2896static struct pci_driver idt_pci_driver = {
2897	.name		= KBUILD_MODNAME,
2898	.probe		= idt_pci_probe,
2899	.remove		= idt_pci_remove,
2900	.id_table	= idt_pci_tbl,
2901};
2902
2903static int __init idt_pci_driver_init(void)
2904{
2905	int ret;
2906	pr_info("%s %s\n", NTB_DESC, NTB_VER);
2907
2908	/* Create the top DebugFS directory if the FS is initialized */
2909	if (debugfs_initialized())
2910		dbgfs_topdir = debugfs_create_dir(KBUILD_MODNAME, NULL);
2911
2912	/* Register the NTB hardware driver to handle the PCI device */
2913	ret = pci_register_driver(&idt_pci_driver);
2914	if (ret)
2915		debugfs_remove_recursive(dbgfs_topdir);
2916
2917	return ret;
2918}
2919module_init(idt_pci_driver_init);
2920
2921static void __exit idt_pci_driver_exit(void)
2922{
2923	/* Unregister the NTB hardware driver */
2924	pci_unregister_driver(&idt_pci_driver);
2925
2926	/* Discard the top DebugFS directory */
2927	debugfs_remove_recursive(dbgfs_topdir);
2928}
2929module_exit(idt_pci_driver_exit);
2930
2931