1/*
2 * AMD 76x Memory Controller kernel module
3 * (C) 2003 Linux Networx (http://lnxi.com)
4 * This file may be distributed under the terms of the
5 * GNU General Public License.
6 *
7 * Written by Thayne Harbaugh
8 * Based on work by Dan Hollis <goemon at anime dot net> and others.
9 *	http://www.anime.net/~goemon/linux-ecc/
10 *
11 * $Id: edac_amd76x.c,v 1.4.2.5 2005/10/05 00:43:44 dsp_llnl Exp $
12 *
13 */
14
15#include <linux/module.h>
16#include <linux/init.h>
17#include <linux/pci.h>
18#include <linux/pci_ids.h>
19#include <linux/edac.h>
20#include "edac_module.h"
21
22#define EDAC_MOD_STR	"amd76x_edac"
23
24#define amd76x_printk(level, fmt, arg...) \
25	edac_printk(level, "amd76x", fmt, ##arg)
26
27#define amd76x_mc_printk(mci, level, fmt, arg...) \
28	edac_mc_chipset_printk(mci, level, "amd76x", fmt, ##arg)
29
30#define AMD76X_NR_CSROWS 8
31#define AMD76X_NR_DIMMS  4
32
33/* AMD 76x register addresses - device 0 function 0 - PCI bridge */
34
35#define AMD76X_ECC_MODE_STATUS	0x48	/* Mode and status of ECC (32b)
36					 *
37					 * 31:16 reserved
38					 * 15:14 SERR enabled: x1=ue 1x=ce
39					 * 13    reserved
40					 * 12    diag: disabled, enabled
41					 * 11:10 mode: dis, EC, ECC, ECC+scrub
42					 *  9:8  status: x1=ue 1x=ce
43					 *  7:4  UE cs row
44					 *  3:0  CE cs row
45					 */
46
47#define AMD76X_DRAM_MODE_STATUS	0x58	/* DRAM Mode and status (32b)
48					 *
49					 * 31:26 clock disable 5 - 0
50					 * 25    SDRAM init
51					 * 24    reserved
52					 * 23    mode register service
53					 * 22:21 suspend to RAM
54					 * 20    burst refresh enable
55					 * 19    refresh disable
56					 * 18    reserved
57					 * 17:16 cycles-per-refresh
58					 * 15:8  reserved
59					 *  7:0  x4 mode enable 7 - 0
60					 */
61
62#define AMD76X_MEM_BASE_ADDR	0xC0	/* Memory base address (8 x 32b)
63					 *
64					 * 31:23 chip-select base
65					 * 22:16 reserved
66					 * 15:7  chip-select mask
67					 *  6:3  reserved
68					 *  2:1  address mode
69					 *  0    chip-select enable
70					 */
71
72struct amd76x_error_info {
73	u32 ecc_mode_status;
74};
75
76enum amd76x_chips {
77	AMD761 = 0,
78	AMD762
79};
80
81struct amd76x_dev_info {
82	const char *ctl_name;
83};
84
85static const struct amd76x_dev_info amd76x_devs[] = {
86	[AMD761] = {
87		.ctl_name = "AMD761"},
88	[AMD762] = {
89		.ctl_name = "AMD762"},
90};
91
92static struct edac_pci_ctl_info *amd76x_pci;
93
94/**
95 *	amd76x_get_error_info	-	fetch error information
96 *	@mci: Memory controller
97 *	@info: Info to fill in
98 *
99 *	Fetch and store the AMD76x ECC status. Clear pending status
100 *	on the chip so that further errors will be reported
101 */
102static void amd76x_get_error_info(struct mem_ctl_info *mci,
103				struct amd76x_error_info *info)
104{
105	struct pci_dev *pdev;
106
107	pdev = to_pci_dev(mci->pdev);
108	pci_read_config_dword(pdev, AMD76X_ECC_MODE_STATUS,
109			&info->ecc_mode_status);
110
111	if (info->ecc_mode_status & BIT(8))
112		pci_write_bits32(pdev, AMD76X_ECC_MODE_STATUS,
113				 (u32) BIT(8), (u32) BIT(8));
114
115	if (info->ecc_mode_status & BIT(9))
116		pci_write_bits32(pdev, AMD76X_ECC_MODE_STATUS,
117				 (u32) BIT(9), (u32) BIT(9));
118}
119
120/**
121 *	amd76x_process_error_info	-	Error check
122 *	@mci: Memory controller
123 *	@info: Previously fetched information from chip
124 *	@handle_errors: 1 if we should do recovery
125 *
126 *	Process the chip state and decide if an error has occurred.
127 *	A return of 1 indicates an error. Also if handle_errors is true
128 *	then attempt to handle and clean up after the error
129 */
130static int amd76x_process_error_info(struct mem_ctl_info *mci,
131				struct amd76x_error_info *info,
132				int handle_errors)
133{
134	int error_found;
135	u32 row;
136
137	error_found = 0;
138
139	/*
140	 *      Check for an uncorrectable error
141	 */
142	if (info->ecc_mode_status & BIT(8)) {
143		error_found = 1;
144
145		if (handle_errors) {
146			row = (info->ecc_mode_status >> 4) & 0xf;
147			edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 1,
148					     mci->csrows[row]->first_page, 0, 0,
149					     row, 0, -1,
150					     mci->ctl_name, "");
151		}
152	}
153
154	/*
155	 *      Check for a correctable error
156	 */
157	if (info->ecc_mode_status & BIT(9)) {
158		error_found = 1;
159
160		if (handle_errors) {
161			row = info->ecc_mode_status & 0xf;
162			edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, 1,
163					     mci->csrows[row]->first_page, 0, 0,
164					     row, 0, -1,
165					     mci->ctl_name, "");
166		}
167	}
168
169	return error_found;
170}
171
172/**
173 *	amd76x_check	-	Poll the controller
174 *	@mci: Memory controller
175 *
176 *	Called by the poll handlers this function reads the status
177 *	from the controller and checks for errors.
178 */
179static void amd76x_check(struct mem_ctl_info *mci)
180{
181	struct amd76x_error_info info;
182	edac_dbg(3, "\n");
183	amd76x_get_error_info(mci, &info);
184	amd76x_process_error_info(mci, &info, 1);
185}
186
187static void amd76x_init_csrows(struct mem_ctl_info *mci, struct pci_dev *pdev,
188			enum edac_type edac_mode)
189{
190	struct csrow_info *csrow;
191	struct dimm_info *dimm;
192	u32 mba, mba_base, mba_mask, dms;
193	int index;
194
195	for (index = 0; index < mci->nr_csrows; index++) {
196		csrow = mci->csrows[index];
197		dimm = csrow->channels[0]->dimm;
198
199		/* find the DRAM Chip Select Base address and mask */
200		pci_read_config_dword(pdev,
201				AMD76X_MEM_BASE_ADDR + (index * 4), &mba);
202
203		if (!(mba & BIT(0)))
204			continue;
205
206		mba_base = mba & 0xff800000UL;
207		mba_mask = ((mba & 0xff80) << 16) | 0x7fffffUL;
208		pci_read_config_dword(pdev, AMD76X_DRAM_MODE_STATUS, &dms);
209		csrow->first_page = mba_base >> PAGE_SHIFT;
210		dimm->nr_pages = (mba_mask + 1) >> PAGE_SHIFT;
211		csrow->last_page = csrow->first_page + dimm->nr_pages - 1;
212		csrow->page_mask = mba_mask >> PAGE_SHIFT;
213		dimm->grain = dimm->nr_pages << PAGE_SHIFT;
214		dimm->mtype = MEM_RDDR;
215		dimm->dtype = ((dms >> index) & 0x1) ? DEV_X4 : DEV_UNKNOWN;
216		dimm->edac_mode = edac_mode;
217	}
218}
219
220/**
221 *	amd76x_probe1	-	Perform set up for detected device
222 *	@pdev; PCI device detected
223 *	@dev_idx: Device type index
224 *
225 *	We have found an AMD76x and now need to set up the memory
226 *	controller status reporting. We configure and set up the
227 *	memory controller reporting and claim the device.
228 */
229static int amd76x_probe1(struct pci_dev *pdev, int dev_idx)
230{
231	static const enum edac_type ems_modes[] = {
232		EDAC_NONE,
233		EDAC_EC,
234		EDAC_SECDED,
235		EDAC_SECDED
236	};
237	struct mem_ctl_info *mci;
238	struct edac_mc_layer layers[2];
239	u32 ems;
240	u32 ems_mode;
241	struct amd76x_error_info discard;
242
243	edac_dbg(0, "\n");
244	pci_read_config_dword(pdev, AMD76X_ECC_MODE_STATUS, &ems);
245	ems_mode = (ems >> 10) & 0x3;
246
247	layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
248	layers[0].size = AMD76X_NR_CSROWS;
249	layers[0].is_virt_csrow = true;
250	layers[1].type = EDAC_MC_LAYER_CHANNEL;
251	layers[1].size = 1;
252	layers[1].is_virt_csrow = false;
253	mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers, 0);
254
255	if (mci == NULL)
256		return -ENOMEM;
257
258	edac_dbg(0, "mci = %p\n", mci);
259	mci->pdev = &pdev->dev;
260	mci->mtype_cap = MEM_FLAG_RDDR;
261	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
262	mci->edac_cap = ems_mode ?
263		(EDAC_FLAG_EC | EDAC_FLAG_SECDED) : EDAC_FLAG_NONE;
264	mci->mod_name = EDAC_MOD_STR;
265	mci->ctl_name = amd76x_devs[dev_idx].ctl_name;
266	mci->dev_name = pci_name(pdev);
267	mci->edac_check = amd76x_check;
268	mci->ctl_page_to_phys = NULL;
269
270	amd76x_init_csrows(mci, pdev, ems_modes[ems_mode]);
271	amd76x_get_error_info(mci, &discard);	/* clear counters */
272
273	/* Here we assume that we will never see multiple instances of this
274	 * type of memory controller.  The ID is therefore hardcoded to 0.
275	 */
276	if (edac_mc_add_mc(mci)) {
277		edac_dbg(3, "failed edac_mc_add_mc()\n");
278		goto fail;
279	}
280
281	/* allocating generic PCI control info */
282	amd76x_pci = edac_pci_create_generic_ctl(&pdev->dev, EDAC_MOD_STR);
283	if (!amd76x_pci) {
284		printk(KERN_WARNING
285			"%s(): Unable to create PCI control\n",
286			__func__);
287		printk(KERN_WARNING
288			"%s(): PCI error report via EDAC not setup\n",
289			__func__);
290	}
291
292	/* get this far and it's successful */
293	edac_dbg(3, "success\n");
294	return 0;
295
296fail:
297	edac_mc_free(mci);
298	return -ENODEV;
299}
300
301/* returns count (>= 0), or negative on error */
302static int amd76x_init_one(struct pci_dev *pdev,
303			   const struct pci_device_id *ent)
304{
305	edac_dbg(0, "\n");
306
307	/* don't need to call pci_enable_device() */
308	return amd76x_probe1(pdev, ent->driver_data);
309}
310
311/**
312 *	amd76x_remove_one	-	driver shutdown
313 *	@pdev: PCI device being handed back
314 *
315 *	Called when the driver is unloaded. Find the matching mci
316 *	structure for the device then delete the mci and free the
317 *	resources.
318 */
319static void amd76x_remove_one(struct pci_dev *pdev)
320{
321	struct mem_ctl_info *mci;
322
323	edac_dbg(0, "\n");
324
325	if (amd76x_pci)
326		edac_pci_release_generic_ctl(amd76x_pci);
327
328	if ((mci = edac_mc_del_mc(&pdev->dev)) == NULL)
329		return;
330
331	edac_mc_free(mci);
332}
333
334static const struct pci_device_id amd76x_pci_tbl[] = {
335	{
336	 PCI_VEND_DEV(AMD, FE_GATE_700C), PCI_ANY_ID, PCI_ANY_ID, 0, 0,
337	 AMD762},
338	{
339	 PCI_VEND_DEV(AMD, FE_GATE_700E), PCI_ANY_ID, PCI_ANY_ID, 0, 0,
340	 AMD761},
341	{
342	 0,
343	 }			/* 0 terminated list. */
344};
345
346MODULE_DEVICE_TABLE(pci, amd76x_pci_tbl);
347
348static struct pci_driver amd76x_driver = {
349	.name = EDAC_MOD_STR,
350	.probe = amd76x_init_one,
351	.remove = amd76x_remove_one,
352	.id_table = amd76x_pci_tbl,
353};
354
355static int __init amd76x_init(void)
356{
357       /* Ensure that the OPSTATE is set correctly for POLL or NMI */
358       opstate_init();
359
360	return pci_register_driver(&amd76x_driver);
361}
362
363static void __exit amd76x_exit(void)
364{
365	pci_unregister_driver(&amd76x_driver);
366}
367
368module_init(amd76x_init);
369module_exit(amd76x_exit);
370
371MODULE_LICENSE("GPL");
372MODULE_AUTHOR("Linux Networx (http://lnxi.com) Thayne Harbaugh");
373MODULE_DESCRIPTION("MC support for AMD 76x memory controllers");
374
375module_param(edac_op_state, int, 0444);
376MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");
377