1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Qualcomm PCIe Endpoint controller driver
4 *
5 * Copyright (c) 2020, The Linux Foundation. All rights reserved.
6 * Author: Siddartha Mohanadoss <smohanad@codeaurora.org
7 *
8 * Copyright (c) 2021, Linaro Ltd.
9 * Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org
10 */
11
12#include <linux/clk.h>
13#include <linux/debugfs.h>
14#include <linux/delay.h>
15#include <linux/gpio/consumer.h>
16#include <linux/interconnect.h>
17#include <linux/mfd/syscon.h>
18#include <linux/phy/pcie.h>
19#include <linux/phy/phy.h>
20#include <linux/platform_device.h>
21#include <linux/pm_domain.h>
22#include <linux/regmap.h>
23#include <linux/reset.h>
24#include <linux/module.h>
25
26#include "pcie-designware.h"
27
28/* PARF registers */
29#define PARF_SYS_CTRL				0x00
30#define PARF_DB_CTRL				0x10
31#define PARF_PM_CTRL				0x20
32#define PARF_MHI_CLOCK_RESET_CTRL		0x174
33#define PARF_MHI_BASE_ADDR_LOWER		0x178
34#define PARF_MHI_BASE_ADDR_UPPER		0x17c
35#define PARF_DEBUG_INT_EN			0x190
36#define PARF_AXI_MSTR_RD_HALT_NO_WRITES		0x1a4
37#define PARF_AXI_MSTR_WR_ADDR_HALT		0x1a8
38#define PARF_Q2A_FLUSH				0x1ac
39#define PARF_LTSSM				0x1b0
40#define PARF_CFG_BITS				0x210
41#define PARF_INT_ALL_STATUS			0x224
42#define PARF_INT_ALL_CLEAR			0x228
43#define PARF_INT_ALL_MASK			0x22c
44#define PARF_SLV_ADDR_MSB_CTRL			0x2c0
45#define PARF_DBI_BASE_ADDR			0x350
46#define PARF_DBI_BASE_ADDR_HI			0x354
47#define PARF_SLV_ADDR_SPACE_SIZE		0x358
48#define PARF_SLV_ADDR_SPACE_SIZE_HI		0x35c
49#define PARF_ATU_BASE_ADDR			0x634
50#define PARF_ATU_BASE_ADDR_HI			0x638
51#define PARF_SRIS_MODE				0x644
52#define PARF_DEBUG_CNT_PM_LINKST_IN_L2		0xc04
53#define PARF_DEBUG_CNT_PM_LINKST_IN_L1		0xc0c
54#define PARF_DEBUG_CNT_PM_LINKST_IN_L0S		0xc10
55#define PARF_DEBUG_CNT_AUX_CLK_IN_L1SUB_L1	0xc84
56#define PARF_DEBUG_CNT_AUX_CLK_IN_L1SUB_L2	0xc88
57#define PARF_DEVICE_TYPE			0x1000
58#define PARF_BDF_TO_SID_CFG			0x2c00
59
60/* PARF_INT_ALL_{STATUS/CLEAR/MASK} register fields */
61#define PARF_INT_ALL_LINK_DOWN			BIT(1)
62#define PARF_INT_ALL_BME			BIT(2)
63#define PARF_INT_ALL_PM_TURNOFF			BIT(3)
64#define PARF_INT_ALL_DEBUG			BIT(4)
65#define PARF_INT_ALL_LTR			BIT(5)
66#define PARF_INT_ALL_MHI_Q6			BIT(6)
67#define PARF_INT_ALL_MHI_A7			BIT(7)
68#define PARF_INT_ALL_DSTATE_CHANGE		BIT(8)
69#define PARF_INT_ALL_L1SUB_TIMEOUT		BIT(9)
70#define PARF_INT_ALL_MMIO_WRITE			BIT(10)
71#define PARF_INT_ALL_CFG_WRITE			BIT(11)
72#define PARF_INT_ALL_BRIDGE_FLUSH_N		BIT(12)
73#define PARF_INT_ALL_LINK_UP			BIT(13)
74#define PARF_INT_ALL_AER_LEGACY			BIT(14)
75#define PARF_INT_ALL_PLS_ERR			BIT(15)
76#define PARF_INT_ALL_PME_LEGACY			BIT(16)
77#define PARF_INT_ALL_PLS_PME			BIT(17)
78#define PARF_INT_ALL_EDMA			BIT(22)
79
80/* PARF_BDF_TO_SID_CFG register fields */
81#define PARF_BDF_TO_SID_BYPASS			BIT(0)
82
83/* PARF_DEBUG_INT_EN register fields */
84#define PARF_DEBUG_INT_PM_DSTATE_CHANGE		BIT(1)
85#define PARF_DEBUG_INT_CFG_BUS_MASTER_EN	BIT(2)
86#define PARF_DEBUG_INT_RADM_PM_TURNOFF		BIT(3)
87
88/* PARF_DEVICE_TYPE register fields */
89#define PARF_DEVICE_TYPE_EP			0x0
90
91/* PARF_PM_CTRL register fields */
92#define PARF_PM_CTRL_REQ_EXIT_L1		BIT(1)
93#define PARF_PM_CTRL_READY_ENTR_L23		BIT(2)
94#define PARF_PM_CTRL_REQ_NOT_ENTR_L1		BIT(5)
95
96/* PARF_MHI_CLOCK_RESET_CTRL fields */
97#define PARF_MSTR_AXI_CLK_EN			BIT(1)
98
99/* PARF_AXI_MSTR_RD_HALT_NO_WRITES register fields */
100#define PARF_AXI_MSTR_RD_HALT_NO_WRITE_EN	BIT(0)
101
102/* PARF_AXI_MSTR_WR_ADDR_HALT register fields */
103#define PARF_AXI_MSTR_WR_ADDR_HALT_EN		BIT(31)
104
105/* PARF_Q2A_FLUSH register fields */
106#define PARF_Q2A_FLUSH_EN			BIT(16)
107
108/* PARF_SYS_CTRL register fields */
109#define PARF_SYS_CTRL_AUX_PWR_DET		BIT(4)
110#define PARF_SYS_CTRL_CORE_CLK_CGC_DIS		BIT(6)
111#define PARF_SYS_CTRL_MSTR_ACLK_CGC_DIS		BIT(10)
112#define PARF_SYS_CTRL_SLV_DBI_WAKE_DISABLE	BIT(11)
113
114/* PARF_DB_CTRL register fields */
115#define PARF_DB_CTRL_INSR_DBNCR_BLOCK		BIT(0)
116#define PARF_DB_CTRL_RMVL_DBNCR_BLOCK		BIT(1)
117#define PARF_DB_CTRL_DBI_WKP_BLOCK		BIT(4)
118#define PARF_DB_CTRL_SLV_WKP_BLOCK		BIT(5)
119#define PARF_DB_CTRL_MST_WKP_BLOCK		BIT(6)
120
121/* PARF_CFG_BITS register fields */
122#define PARF_CFG_BITS_REQ_EXIT_L1SS_MSI_LTR_EN	BIT(1)
123
124/* ELBI registers */
125#define ELBI_SYS_STTS				0x08
126#define ELBI_CS2_ENABLE				0xa4
127
128/* DBI registers */
129#define DBI_CON_STATUS				0x44
130
131/* DBI register fields */
132#define DBI_CON_STATUS_POWER_STATE_MASK		GENMASK(1, 0)
133
134#define XMLH_LINK_UP				0x400
135#define CORE_RESET_TIME_US_MIN			1000
136#define CORE_RESET_TIME_US_MAX			1005
137#define WAKE_DELAY_US				2000 /* 2 ms */
138
139#define PCIE_GEN1_BW_MBPS			250
140#define PCIE_GEN2_BW_MBPS			500
141#define PCIE_GEN3_BW_MBPS			985
142#define PCIE_GEN4_BW_MBPS			1969
143
144#define to_pcie_ep(x)				dev_get_drvdata((x)->dev)
145
146enum qcom_pcie_ep_link_status {
147	QCOM_PCIE_EP_LINK_DISABLED,
148	QCOM_PCIE_EP_LINK_ENABLED,
149	QCOM_PCIE_EP_LINK_UP,
150	QCOM_PCIE_EP_LINK_DOWN,
151};
152
153/**
154 * struct qcom_pcie_ep - Qualcomm PCIe Endpoint Controller
155 * @pci: Designware PCIe controller struct
156 * @parf: Qualcomm PCIe specific PARF register base
157 * @elbi: Designware PCIe specific ELBI register base
158 * @mmio: MMIO register base
159 * @perst_map: PERST regmap
160 * @mmio_res: MMIO region resource
161 * @core_reset: PCIe Endpoint core reset
162 * @reset: PERST# GPIO
163 * @wake: WAKE# GPIO
164 * @phy: PHY controller block
165 * @debugfs: PCIe Endpoint Debugfs directory
166 * @icc_mem: Handle to an interconnect path between PCIe and MEM
167 * @clks: PCIe clocks
168 * @num_clks: PCIe clocks count
169 * @perst_en: Flag for PERST enable
170 * @perst_sep_en: Flag for PERST separation enable
171 * @link_status: PCIe Link status
172 * @global_irq: Qualcomm PCIe specific Global IRQ
173 * @perst_irq: PERST# IRQ
174 */
175struct qcom_pcie_ep {
176	struct dw_pcie pci;
177
178	void __iomem *parf;
179	void __iomem *elbi;
180	void __iomem *mmio;
181	struct regmap *perst_map;
182	struct resource *mmio_res;
183
184	struct reset_control *core_reset;
185	struct gpio_desc *reset;
186	struct gpio_desc *wake;
187	struct phy *phy;
188	struct dentry *debugfs;
189
190	struct icc_path *icc_mem;
191
192	struct clk_bulk_data *clks;
193	int num_clks;
194
195	u32 perst_en;
196	u32 perst_sep_en;
197
198	enum qcom_pcie_ep_link_status link_status;
199	int global_irq;
200	int perst_irq;
201};
202
203static int qcom_pcie_ep_core_reset(struct qcom_pcie_ep *pcie_ep)
204{
205	struct dw_pcie *pci = &pcie_ep->pci;
206	struct device *dev = pci->dev;
207	int ret;
208
209	ret = reset_control_assert(pcie_ep->core_reset);
210	if (ret) {
211		dev_err(dev, "Cannot assert core reset\n");
212		return ret;
213	}
214
215	usleep_range(CORE_RESET_TIME_US_MIN, CORE_RESET_TIME_US_MAX);
216
217	ret = reset_control_deassert(pcie_ep->core_reset);
218	if (ret) {
219		dev_err(dev, "Cannot de-assert core reset\n");
220		return ret;
221	}
222
223	usleep_range(CORE_RESET_TIME_US_MIN, CORE_RESET_TIME_US_MAX);
224
225	return 0;
226}
227
228/*
229 * Delatch PERST_EN and PERST_SEPARATION_ENABLE with TCSR to avoid
230 * device reset during host reboot and hibernation. The driver is
231 * expected to handle this situation.
232 */
233static void qcom_pcie_ep_configure_tcsr(struct qcom_pcie_ep *pcie_ep)
234{
235	if (pcie_ep->perst_map) {
236		regmap_write(pcie_ep->perst_map, pcie_ep->perst_en, 0);
237		regmap_write(pcie_ep->perst_map, pcie_ep->perst_sep_en, 0);
238	}
239}
240
241static int qcom_pcie_dw_link_up(struct dw_pcie *pci)
242{
243	struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci);
244	u32 reg;
245
246	reg = readl_relaxed(pcie_ep->elbi + ELBI_SYS_STTS);
247
248	return reg & XMLH_LINK_UP;
249}
250
251static int qcom_pcie_dw_start_link(struct dw_pcie *pci)
252{
253	struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci);
254
255	enable_irq(pcie_ep->perst_irq);
256
257	return 0;
258}
259
260static void qcom_pcie_dw_stop_link(struct dw_pcie *pci)
261{
262	struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci);
263
264	disable_irq(pcie_ep->perst_irq);
265}
266
267static void qcom_pcie_dw_write_dbi2(struct dw_pcie *pci, void __iomem *base,
268				    u32 reg, size_t size, u32 val)
269{
270	struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci);
271	int ret;
272
273	writel(1, pcie_ep->elbi + ELBI_CS2_ENABLE);
274
275	ret = dw_pcie_write(pci->dbi_base2 + reg, size, val);
276	if (ret)
277		dev_err(pci->dev, "Failed to write DBI2 register (0x%x): %d\n", reg, ret);
278
279	writel(0, pcie_ep->elbi + ELBI_CS2_ENABLE);
280}
281
282static void qcom_pcie_ep_icc_update(struct qcom_pcie_ep *pcie_ep)
283{
284	struct dw_pcie *pci = &pcie_ep->pci;
285	u32 offset, status, bw;
286	int speed, width;
287	int ret;
288
289	if (!pcie_ep->icc_mem)
290		return;
291
292	offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
293	status = readw(pci->dbi_base + offset + PCI_EXP_LNKSTA);
294
295	speed = FIELD_GET(PCI_EXP_LNKSTA_CLS, status);
296	width = FIELD_GET(PCI_EXP_LNKSTA_NLW, status);
297
298	switch (speed) {
299	case 1:
300		bw = MBps_to_icc(PCIE_GEN1_BW_MBPS);
301		break;
302	case 2:
303		bw = MBps_to_icc(PCIE_GEN2_BW_MBPS);
304		break;
305	case 3:
306		bw = MBps_to_icc(PCIE_GEN3_BW_MBPS);
307		break;
308	default:
309		dev_warn(pci->dev, "using default GEN4 bandwidth\n");
310		fallthrough;
311	case 4:
312		bw = MBps_to_icc(PCIE_GEN4_BW_MBPS);
313		break;
314	}
315
316	ret = icc_set_bw(pcie_ep->icc_mem, 0, width * bw);
317	if (ret)
318		dev_err(pci->dev, "failed to set interconnect bandwidth: %d\n",
319			ret);
320}
321
322static int qcom_pcie_enable_resources(struct qcom_pcie_ep *pcie_ep)
323{
324	struct dw_pcie *pci = &pcie_ep->pci;
325	int ret;
326
327	ret = clk_bulk_prepare_enable(pcie_ep->num_clks, pcie_ep->clks);
328	if (ret)
329		return ret;
330
331	ret = qcom_pcie_ep_core_reset(pcie_ep);
332	if (ret)
333		goto err_disable_clk;
334
335	ret = phy_init(pcie_ep->phy);
336	if (ret)
337		goto err_disable_clk;
338
339	ret = phy_set_mode_ext(pcie_ep->phy, PHY_MODE_PCIE, PHY_MODE_PCIE_EP);
340	if (ret)
341		goto err_phy_exit;
342
343	ret = phy_power_on(pcie_ep->phy);
344	if (ret)
345		goto err_phy_exit;
346
347	/*
348	 * Some Qualcomm platforms require interconnect bandwidth constraints
349	 * to be set before enabling interconnect clocks.
350	 *
351	 * Set an initial peak bandwidth corresponding to single-lane Gen 1
352	 * for the pcie-mem path.
353	 */
354	ret = icc_set_bw(pcie_ep->icc_mem, 0, MBps_to_icc(PCIE_GEN1_BW_MBPS));
355	if (ret) {
356		dev_err(pci->dev, "failed to set interconnect bandwidth: %d\n",
357			ret);
358		goto err_phy_off;
359	}
360
361	return 0;
362
363err_phy_off:
364	phy_power_off(pcie_ep->phy);
365err_phy_exit:
366	phy_exit(pcie_ep->phy);
367err_disable_clk:
368	clk_bulk_disable_unprepare(pcie_ep->num_clks, pcie_ep->clks);
369
370	return ret;
371}
372
373static void qcom_pcie_disable_resources(struct qcom_pcie_ep *pcie_ep)
374{
375	icc_set_bw(pcie_ep->icc_mem, 0, 0);
376	phy_power_off(pcie_ep->phy);
377	phy_exit(pcie_ep->phy);
378	clk_bulk_disable_unprepare(pcie_ep->num_clks, pcie_ep->clks);
379}
380
381static int qcom_pcie_perst_deassert(struct dw_pcie *pci)
382{
383	struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci);
384	struct device *dev = pci->dev;
385	u32 val, offset;
386	int ret;
387
388	ret = qcom_pcie_enable_resources(pcie_ep);
389	if (ret) {
390		dev_err(dev, "Failed to enable resources: %d\n", ret);
391		return ret;
392	}
393
394	/* Assert WAKE# to RC to indicate device is ready */
395	gpiod_set_value_cansleep(pcie_ep->wake, 1);
396	usleep_range(WAKE_DELAY_US, WAKE_DELAY_US + 500);
397	gpiod_set_value_cansleep(pcie_ep->wake, 0);
398
399	qcom_pcie_ep_configure_tcsr(pcie_ep);
400
401	/* Disable BDF to SID mapping */
402	val = readl_relaxed(pcie_ep->parf + PARF_BDF_TO_SID_CFG);
403	val |= PARF_BDF_TO_SID_BYPASS;
404	writel_relaxed(val, pcie_ep->parf + PARF_BDF_TO_SID_CFG);
405
406	/* Enable debug IRQ */
407	val = readl_relaxed(pcie_ep->parf + PARF_DEBUG_INT_EN);
408	val |= PARF_DEBUG_INT_RADM_PM_TURNOFF |
409	       PARF_DEBUG_INT_CFG_BUS_MASTER_EN |
410	       PARF_DEBUG_INT_PM_DSTATE_CHANGE;
411	writel_relaxed(val, pcie_ep->parf + PARF_DEBUG_INT_EN);
412
413	/* Configure PCIe to endpoint mode */
414	writel_relaxed(PARF_DEVICE_TYPE_EP, pcie_ep->parf + PARF_DEVICE_TYPE);
415
416	/* Allow entering L1 state */
417	val = readl_relaxed(pcie_ep->parf + PARF_PM_CTRL);
418	val &= ~PARF_PM_CTRL_REQ_NOT_ENTR_L1;
419	writel_relaxed(val, pcie_ep->parf + PARF_PM_CTRL);
420
421	/* Read halts write */
422	val = readl_relaxed(pcie_ep->parf + PARF_AXI_MSTR_RD_HALT_NO_WRITES);
423	val &= ~PARF_AXI_MSTR_RD_HALT_NO_WRITE_EN;
424	writel_relaxed(val, pcie_ep->parf + PARF_AXI_MSTR_RD_HALT_NO_WRITES);
425
426	/* Write after write halt */
427	val = readl_relaxed(pcie_ep->parf + PARF_AXI_MSTR_WR_ADDR_HALT);
428	val |= PARF_AXI_MSTR_WR_ADDR_HALT_EN;
429	writel_relaxed(val, pcie_ep->parf + PARF_AXI_MSTR_WR_ADDR_HALT);
430
431	/* Q2A flush disable */
432	val = readl_relaxed(pcie_ep->parf + PARF_Q2A_FLUSH);
433	val &= ~PARF_Q2A_FLUSH_EN;
434	writel_relaxed(val, pcie_ep->parf + PARF_Q2A_FLUSH);
435
436	/*
437	 * Disable Master AXI clock during idle.  Do not allow DBI access
438	 * to take the core out of L1.  Disable core clock gating that
439	 * gates PIPE clock from propagating to core clock.  Report to the
440	 * host that Vaux is present.
441	 */
442	val = readl_relaxed(pcie_ep->parf + PARF_SYS_CTRL);
443	val &= ~PARF_SYS_CTRL_MSTR_ACLK_CGC_DIS;
444	val |= PARF_SYS_CTRL_SLV_DBI_WAKE_DISABLE |
445	       PARF_SYS_CTRL_CORE_CLK_CGC_DIS |
446	       PARF_SYS_CTRL_AUX_PWR_DET;
447	writel_relaxed(val, pcie_ep->parf + PARF_SYS_CTRL);
448
449	/* Disable the debouncers */
450	val = readl_relaxed(pcie_ep->parf + PARF_DB_CTRL);
451	val |= PARF_DB_CTRL_INSR_DBNCR_BLOCK | PARF_DB_CTRL_RMVL_DBNCR_BLOCK |
452	       PARF_DB_CTRL_DBI_WKP_BLOCK | PARF_DB_CTRL_SLV_WKP_BLOCK |
453	       PARF_DB_CTRL_MST_WKP_BLOCK;
454	writel_relaxed(val, pcie_ep->parf + PARF_DB_CTRL);
455
456	/* Request to exit from L1SS for MSI and LTR MSG */
457	val = readl_relaxed(pcie_ep->parf + PARF_CFG_BITS);
458	val |= PARF_CFG_BITS_REQ_EXIT_L1SS_MSI_LTR_EN;
459	writel_relaxed(val, pcie_ep->parf + PARF_CFG_BITS);
460
461	dw_pcie_dbi_ro_wr_en(pci);
462
463	/* Set the L0s Exit Latency to 2us-4us = 0x6 */
464	offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
465	val = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP);
466	val &= ~PCI_EXP_LNKCAP_L0SEL;
467	val |= FIELD_PREP(PCI_EXP_LNKCAP_L0SEL, 0x6);
468	dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, val);
469
470	/* Set the L1 Exit Latency to be 32us-64 us = 0x6 */
471	offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
472	val = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP);
473	val &= ~PCI_EXP_LNKCAP_L1EL;
474	val |= FIELD_PREP(PCI_EXP_LNKCAP_L1EL, 0x6);
475	dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, val);
476
477	dw_pcie_dbi_ro_wr_dis(pci);
478
479	writel_relaxed(0, pcie_ep->parf + PARF_INT_ALL_MASK);
480	val = PARF_INT_ALL_LINK_DOWN | PARF_INT_ALL_BME |
481	      PARF_INT_ALL_PM_TURNOFF | PARF_INT_ALL_DSTATE_CHANGE |
482	      PARF_INT_ALL_LINK_UP | PARF_INT_ALL_EDMA;
483	writel_relaxed(val, pcie_ep->parf + PARF_INT_ALL_MASK);
484
485	ret = dw_pcie_ep_init_complete(&pcie_ep->pci.ep);
486	if (ret) {
487		dev_err(dev, "Failed to complete initialization: %d\n", ret);
488		goto err_disable_resources;
489	}
490
491	/*
492	 * The physical address of the MMIO region which is exposed as the BAR
493	 * should be written to MHI BASE registers.
494	 */
495	writel_relaxed(pcie_ep->mmio_res->start,
496		       pcie_ep->parf + PARF_MHI_BASE_ADDR_LOWER);
497	writel_relaxed(0, pcie_ep->parf + PARF_MHI_BASE_ADDR_UPPER);
498
499	/* Gate Master AXI clock to MHI bus during L1SS */
500	val = readl_relaxed(pcie_ep->parf + PARF_MHI_CLOCK_RESET_CTRL);
501	val &= ~PARF_MSTR_AXI_CLK_EN;
502	writel_relaxed(val, pcie_ep->parf + PARF_MHI_CLOCK_RESET_CTRL);
503
504	dw_pcie_ep_init_notify(&pcie_ep->pci.ep);
505
506	/* Enable LTSSM */
507	val = readl_relaxed(pcie_ep->parf + PARF_LTSSM);
508	val |= BIT(8);
509	writel_relaxed(val, pcie_ep->parf + PARF_LTSSM);
510
511	return 0;
512
513err_disable_resources:
514	qcom_pcie_disable_resources(pcie_ep);
515
516	return ret;
517}
518
519static void qcom_pcie_perst_assert(struct dw_pcie *pci)
520{
521	struct qcom_pcie_ep *pcie_ep = to_pcie_ep(pci);
522	struct device *dev = pci->dev;
523
524	if (pcie_ep->link_status == QCOM_PCIE_EP_LINK_DISABLED) {
525		dev_dbg(dev, "Link is already disabled\n");
526		return;
527	}
528
529	qcom_pcie_disable_resources(pcie_ep);
530	pcie_ep->link_status = QCOM_PCIE_EP_LINK_DISABLED;
531}
532
533/* Common DWC controller ops */
534static const struct dw_pcie_ops pci_ops = {
535	.link_up = qcom_pcie_dw_link_up,
536	.start_link = qcom_pcie_dw_start_link,
537	.stop_link = qcom_pcie_dw_stop_link,
538	.write_dbi2 = qcom_pcie_dw_write_dbi2,
539};
540
541static int qcom_pcie_ep_get_io_resources(struct platform_device *pdev,
542					 struct qcom_pcie_ep *pcie_ep)
543{
544	struct device *dev = &pdev->dev;
545	struct dw_pcie *pci = &pcie_ep->pci;
546	struct device_node *syscon;
547	struct resource *res;
548	int ret;
549
550	pcie_ep->parf = devm_platform_ioremap_resource_byname(pdev, "parf");
551	if (IS_ERR(pcie_ep->parf))
552		return PTR_ERR(pcie_ep->parf);
553
554	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi");
555	pci->dbi_base = devm_pci_remap_cfg_resource(dev, res);
556	if (IS_ERR(pci->dbi_base))
557		return PTR_ERR(pci->dbi_base);
558	pci->dbi_base2 = pci->dbi_base;
559
560	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "elbi");
561	pcie_ep->elbi = devm_pci_remap_cfg_resource(dev, res);
562	if (IS_ERR(pcie_ep->elbi))
563		return PTR_ERR(pcie_ep->elbi);
564
565	pcie_ep->mmio_res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
566							 "mmio");
567	if (!pcie_ep->mmio_res) {
568		dev_err(dev, "Failed to get mmio resource\n");
569		return -EINVAL;
570	}
571
572	pcie_ep->mmio = devm_pci_remap_cfg_resource(dev, pcie_ep->mmio_res);
573	if (IS_ERR(pcie_ep->mmio))
574		return PTR_ERR(pcie_ep->mmio);
575
576	syscon = of_parse_phandle(dev->of_node, "qcom,perst-regs", 0);
577	if (!syscon) {
578		dev_dbg(dev, "PERST separation not available\n");
579		return 0;
580	}
581
582	pcie_ep->perst_map = syscon_node_to_regmap(syscon);
583	of_node_put(syscon);
584	if (IS_ERR(pcie_ep->perst_map))
585		return PTR_ERR(pcie_ep->perst_map);
586
587	ret = of_property_read_u32_index(dev->of_node, "qcom,perst-regs",
588					 1, &pcie_ep->perst_en);
589	if (ret < 0) {
590		dev_err(dev, "No Perst Enable offset in syscon\n");
591		return ret;
592	}
593
594	ret = of_property_read_u32_index(dev->of_node, "qcom,perst-regs",
595					 2, &pcie_ep->perst_sep_en);
596	if (ret < 0) {
597		dev_err(dev, "No Perst Separation Enable offset in syscon\n");
598		return ret;
599	}
600
601	return 0;
602}
603
604static int qcom_pcie_ep_get_resources(struct platform_device *pdev,
605				      struct qcom_pcie_ep *pcie_ep)
606{
607	struct device *dev = &pdev->dev;
608	int ret;
609
610	ret = qcom_pcie_ep_get_io_resources(pdev, pcie_ep);
611	if (ret) {
612		dev_err(dev, "Failed to get io resources %d\n", ret);
613		return ret;
614	}
615
616	pcie_ep->num_clks = devm_clk_bulk_get_all(dev, &pcie_ep->clks);
617	if (pcie_ep->num_clks < 0) {
618		dev_err(dev, "Failed to get clocks\n");
619		return pcie_ep->num_clks;
620	}
621
622	pcie_ep->core_reset = devm_reset_control_get_exclusive(dev, "core");
623	if (IS_ERR(pcie_ep->core_reset))
624		return PTR_ERR(pcie_ep->core_reset);
625
626	pcie_ep->reset = devm_gpiod_get(dev, "reset", GPIOD_IN);
627	if (IS_ERR(pcie_ep->reset))
628		return PTR_ERR(pcie_ep->reset);
629
630	pcie_ep->wake = devm_gpiod_get_optional(dev, "wake", GPIOD_OUT_LOW);
631	if (IS_ERR(pcie_ep->wake))
632		return PTR_ERR(pcie_ep->wake);
633
634	pcie_ep->phy = devm_phy_optional_get(dev, "pciephy");
635	if (IS_ERR(pcie_ep->phy))
636		ret = PTR_ERR(pcie_ep->phy);
637
638	pcie_ep->icc_mem = devm_of_icc_get(dev, "pcie-mem");
639	if (IS_ERR(pcie_ep->icc_mem))
640		ret = PTR_ERR(pcie_ep->icc_mem);
641
642	return ret;
643}
644
645/* TODO: Notify clients about PCIe state change */
646static irqreturn_t qcom_pcie_ep_global_irq_thread(int irq, void *data)
647{
648	struct qcom_pcie_ep *pcie_ep = data;
649	struct dw_pcie *pci = &pcie_ep->pci;
650	struct device *dev = pci->dev;
651	u32 status = readl_relaxed(pcie_ep->parf + PARF_INT_ALL_STATUS);
652	u32 mask = readl_relaxed(pcie_ep->parf + PARF_INT_ALL_MASK);
653	u32 dstate, val;
654
655	writel_relaxed(status, pcie_ep->parf + PARF_INT_ALL_CLEAR);
656	status &= mask;
657
658	if (FIELD_GET(PARF_INT_ALL_LINK_DOWN, status)) {
659		dev_dbg(dev, "Received Linkdown event\n");
660		pcie_ep->link_status = QCOM_PCIE_EP_LINK_DOWN;
661		pci_epc_linkdown(pci->ep.epc);
662	} else if (FIELD_GET(PARF_INT_ALL_BME, status)) {
663		dev_dbg(dev, "Received BME event. Link is enabled!\n");
664		pcie_ep->link_status = QCOM_PCIE_EP_LINK_ENABLED;
665		qcom_pcie_ep_icc_update(pcie_ep);
666		pci_epc_bme_notify(pci->ep.epc);
667	} else if (FIELD_GET(PARF_INT_ALL_PM_TURNOFF, status)) {
668		dev_dbg(dev, "Received PM Turn-off event! Entering L23\n");
669		val = readl_relaxed(pcie_ep->parf + PARF_PM_CTRL);
670		val |= PARF_PM_CTRL_READY_ENTR_L23;
671		writel_relaxed(val, pcie_ep->parf + PARF_PM_CTRL);
672	} else if (FIELD_GET(PARF_INT_ALL_DSTATE_CHANGE, status)) {
673		dstate = dw_pcie_readl_dbi(pci, DBI_CON_STATUS) &
674					   DBI_CON_STATUS_POWER_STATE_MASK;
675		dev_dbg(dev, "Received D%d state event\n", dstate);
676		if (dstate == 3) {
677			val = readl_relaxed(pcie_ep->parf + PARF_PM_CTRL);
678			val |= PARF_PM_CTRL_REQ_EXIT_L1;
679			writel_relaxed(val, pcie_ep->parf + PARF_PM_CTRL);
680		}
681	} else if (FIELD_GET(PARF_INT_ALL_LINK_UP, status)) {
682		dev_dbg(dev, "Received Linkup event. Enumeration complete!\n");
683		dw_pcie_ep_linkup(&pci->ep);
684		pcie_ep->link_status = QCOM_PCIE_EP_LINK_UP;
685	} else {
686		dev_err(dev, "Received unknown event: %d\n", status);
687	}
688
689	return IRQ_HANDLED;
690}
691
692static irqreturn_t qcom_pcie_ep_perst_irq_thread(int irq, void *data)
693{
694	struct qcom_pcie_ep *pcie_ep = data;
695	struct dw_pcie *pci = &pcie_ep->pci;
696	struct device *dev = pci->dev;
697	u32 perst;
698
699	perst = gpiod_get_value(pcie_ep->reset);
700	if (perst) {
701		dev_dbg(dev, "PERST asserted by host. Shutting down the PCIe link!\n");
702		qcom_pcie_perst_assert(pci);
703	} else {
704		dev_dbg(dev, "PERST de-asserted by host. Starting link training!\n");
705		qcom_pcie_perst_deassert(pci);
706	}
707
708	irq_set_irq_type(gpiod_to_irq(pcie_ep->reset),
709			 (perst ? IRQF_TRIGGER_HIGH : IRQF_TRIGGER_LOW));
710
711	return IRQ_HANDLED;
712}
713
714static int qcom_pcie_ep_enable_irq_resources(struct platform_device *pdev,
715					     struct qcom_pcie_ep *pcie_ep)
716{
717	int ret;
718
719	pcie_ep->global_irq = platform_get_irq_byname(pdev, "global");
720	if (pcie_ep->global_irq < 0)
721		return pcie_ep->global_irq;
722
723	ret = devm_request_threaded_irq(&pdev->dev, pcie_ep->global_irq, NULL,
724					qcom_pcie_ep_global_irq_thread,
725					IRQF_ONESHOT,
726					"global_irq", pcie_ep);
727	if (ret) {
728		dev_err(&pdev->dev, "Failed to request Global IRQ\n");
729		return ret;
730	}
731
732	pcie_ep->perst_irq = gpiod_to_irq(pcie_ep->reset);
733	irq_set_status_flags(pcie_ep->perst_irq, IRQ_NOAUTOEN);
734	ret = devm_request_threaded_irq(&pdev->dev, pcie_ep->perst_irq, NULL,
735					qcom_pcie_ep_perst_irq_thread,
736					IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
737					"perst_irq", pcie_ep);
738	if (ret) {
739		dev_err(&pdev->dev, "Failed to request PERST IRQ\n");
740		disable_irq(pcie_ep->global_irq);
741		return ret;
742	}
743
744	return 0;
745}
746
747static int qcom_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no,
748				  enum pci_epc_irq_type type, u16 interrupt_num)
749{
750	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
751
752	switch (type) {
753	case PCI_EPC_IRQ_LEGACY:
754		return dw_pcie_ep_raise_legacy_irq(ep, func_no);
755	case PCI_EPC_IRQ_MSI:
756		return dw_pcie_ep_raise_msi_irq(ep, func_no, interrupt_num);
757	default:
758		dev_err(pci->dev, "Unknown IRQ type\n");
759		return -EINVAL;
760	}
761}
762
763static int qcom_pcie_ep_link_transition_count(struct seq_file *s, void *data)
764{
765	struct qcom_pcie_ep *pcie_ep = (struct qcom_pcie_ep *)
766				     dev_get_drvdata(s->private);
767
768	seq_printf(s, "L0s transition count: %u\n",
769		   readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_PM_LINKST_IN_L0S));
770
771	seq_printf(s, "L1 transition count: %u\n",
772		   readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_PM_LINKST_IN_L1));
773
774	seq_printf(s, "L1.1 transition count: %u\n",
775		   readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_AUX_CLK_IN_L1SUB_L1));
776
777	seq_printf(s, "L1.2 transition count: %u\n",
778		   readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_AUX_CLK_IN_L1SUB_L2));
779
780	seq_printf(s, "L2 transition count: %u\n",
781		   readl_relaxed(pcie_ep->mmio + PARF_DEBUG_CNT_PM_LINKST_IN_L2));
782
783	return 0;
784}
785
786static void qcom_pcie_ep_init_debugfs(struct qcom_pcie_ep *pcie_ep)
787{
788	struct dw_pcie *pci = &pcie_ep->pci;
789
790	debugfs_create_devm_seqfile(pci->dev, "link_transition_count", pcie_ep->debugfs,
791				    qcom_pcie_ep_link_transition_count);
792}
793
794static const struct pci_epc_features qcom_pcie_epc_features = {
795	.linkup_notifier = true,
796	.core_init_notifier = true,
797	.msi_capable = true,
798	.msix_capable = false,
799	.align = SZ_4K,
800};
801
802static const struct pci_epc_features *
803qcom_pcie_epc_get_features(struct dw_pcie_ep *pci_ep)
804{
805	return &qcom_pcie_epc_features;
806}
807
808static void qcom_pcie_ep_init(struct dw_pcie_ep *ep)
809{
810	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
811	enum pci_barno bar;
812
813	for (bar = BAR_0; bar <= BAR_5; bar++)
814		dw_pcie_ep_reset_bar(pci, bar);
815}
816
817static const struct dw_pcie_ep_ops pci_ep_ops = {
818	.ep_init = qcom_pcie_ep_init,
819	.raise_irq = qcom_pcie_ep_raise_irq,
820	.get_features = qcom_pcie_epc_get_features,
821};
822
823static int qcom_pcie_ep_probe(struct platform_device *pdev)
824{
825	struct device *dev = &pdev->dev;
826	struct qcom_pcie_ep *pcie_ep;
827	char *name;
828	int ret;
829
830	pcie_ep = devm_kzalloc(dev, sizeof(*pcie_ep), GFP_KERNEL);
831	if (!pcie_ep)
832		return -ENOMEM;
833
834	pcie_ep->pci.dev = dev;
835	pcie_ep->pci.ops = &pci_ops;
836	pcie_ep->pci.ep.ops = &pci_ep_ops;
837	pcie_ep->pci.edma.nr_irqs = 1;
838	platform_set_drvdata(pdev, pcie_ep);
839
840	ret = qcom_pcie_ep_get_resources(pdev, pcie_ep);
841	if (ret)
842		return ret;
843
844	ret = qcom_pcie_enable_resources(pcie_ep);
845	if (ret) {
846		dev_err(dev, "Failed to enable resources: %d\n", ret);
847		return ret;
848	}
849
850	ret = dw_pcie_ep_init(&pcie_ep->pci.ep);
851	if (ret) {
852		dev_err(dev, "Failed to initialize endpoint: %d\n", ret);
853		goto err_disable_resources;
854	}
855
856	ret = qcom_pcie_ep_enable_irq_resources(pdev, pcie_ep);
857	if (ret)
858		goto err_disable_resources;
859
860	name = devm_kasprintf(dev, GFP_KERNEL, "%pOFP", dev->of_node);
861	if (!name) {
862		ret = -ENOMEM;
863		goto err_disable_irqs;
864	}
865
866	pcie_ep->debugfs = debugfs_create_dir(name, NULL);
867	qcom_pcie_ep_init_debugfs(pcie_ep);
868
869	return 0;
870
871err_disable_irqs:
872	disable_irq(pcie_ep->global_irq);
873	disable_irq(pcie_ep->perst_irq);
874
875err_disable_resources:
876	qcom_pcie_disable_resources(pcie_ep);
877
878	return ret;
879}
880
881static void qcom_pcie_ep_remove(struct platform_device *pdev)
882{
883	struct qcom_pcie_ep *pcie_ep = platform_get_drvdata(pdev);
884
885	disable_irq(pcie_ep->global_irq);
886	disable_irq(pcie_ep->perst_irq);
887
888	debugfs_remove_recursive(pcie_ep->debugfs);
889
890	if (pcie_ep->link_status == QCOM_PCIE_EP_LINK_DISABLED)
891		return;
892
893	qcom_pcie_disable_resources(pcie_ep);
894}
895
896static const struct of_device_id qcom_pcie_ep_match[] = {
897	{ .compatible = "qcom,sdx55-pcie-ep", },
898	{ .compatible = "qcom,sm8450-pcie-ep", },
899	{ }
900};
901MODULE_DEVICE_TABLE(of, qcom_pcie_ep_match);
902
903static struct platform_driver qcom_pcie_ep_driver = {
904	.probe	= qcom_pcie_ep_probe,
905	.remove_new = qcom_pcie_ep_remove,
906	.driver	= {
907		.name = "qcom-pcie-ep",
908		.of_match_table	= qcom_pcie_ep_match,
909	},
910};
911builtin_platform_driver(qcom_pcie_ep_driver);
912
913MODULE_AUTHOR("Siddartha Mohanadoss <smohanad@codeaurora.org>");
914MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
915MODULE_DESCRIPTION("Qualcomm PCIe Endpoint controller driver");
916MODULE_LICENSE("GPL v2");
917