xref: /openbmc/linux/drivers/edac/amd76x_edac.c (revision 64c70b1c)
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/slab.h>
20 #include "edac_mc.h"
21 
22 #define AMD76X_REVISION	" Ver: 2.0.1 "  __DATE__
23 #define EDAC_MOD_STR	"amd76x_edac"
24 
25 #define amd76x_printk(level, fmt, arg...) \
26 	edac_printk(level, "amd76x", fmt, ##arg)
27 
28 #define amd76x_mc_printk(mci, level, fmt, arg...) \
29 	edac_mc_chipset_printk(mci, level, "amd76x", fmt, ##arg)
30 
31 #define AMD76X_NR_CSROWS 8
32 #define AMD76X_NR_CHANS  1
33 #define AMD76X_NR_DIMMS  4
34 
35 /* AMD 76x register addresses - device 0 function 0 - PCI bridge */
36 
37 #define AMD76X_ECC_MODE_STATUS	0x48	/* Mode and status of ECC (32b)
38 					 *
39 					 * 31:16 reserved
40 					 * 15:14 SERR enabled: x1=ue 1x=ce
41 					 * 13    reserved
42 					 * 12    diag: disabled, enabled
43 					 * 11:10 mode: dis, EC, ECC, ECC+scrub
44 					 *  9:8  status: x1=ue 1x=ce
45 					 *  7:4  UE cs row
46 					 *  3:0  CE cs row
47 					 */
48 
49 #define AMD76X_DRAM_MODE_STATUS	0x58	/* DRAM Mode and status (32b)
50 					 *
51 					 * 31:26 clock disable 5 - 0
52 					 * 25    SDRAM init
53 					 * 24    reserved
54 					 * 23    mode register service
55 					 * 22:21 suspend to RAM
56 					 * 20    burst refresh enable
57 					 * 19    refresh disable
58 					 * 18    reserved
59 					 * 17:16 cycles-per-refresh
60 					 * 15:8  reserved
61 					 *  7:0  x4 mode enable 7 - 0
62 					 */
63 
64 #define AMD76X_MEM_BASE_ADDR	0xC0	/* Memory base address (8 x 32b)
65 					 *
66 					 * 31:23 chip-select base
67 					 * 22:16 reserved
68 					 * 15:7  chip-select mask
69 					 *  6:3  reserved
70 					 *  2:1  address mode
71 					 *  0    chip-select enable
72 					 */
73 
74 struct amd76x_error_info {
75 	u32 ecc_mode_status;
76 };
77 
78 enum amd76x_chips {
79 	AMD761 = 0,
80 	AMD762
81 };
82 
83 struct amd76x_dev_info {
84 	const char *ctl_name;
85 };
86 
87 static const struct amd76x_dev_info amd76x_devs[] = {
88 	[AMD761] = {
89 		.ctl_name = "AMD761"
90 	},
91 	[AMD762] = {
92 		.ctl_name = "AMD762"
93 	},
94 };
95 
96 /**
97  *	amd76x_get_error_info	-	fetch error information
98  *	@mci: Memory controller
99  *	@info: Info to fill in
100  *
101  *	Fetch and store the AMD76x ECC status. Clear pending status
102  *	on the chip so that further errors will be reported
103  */
104 static void amd76x_get_error_info(struct mem_ctl_info *mci,
105 		struct amd76x_error_info *info)
106 {
107 	struct pci_dev *pdev;
108 
109 	pdev = to_pci_dev(mci->dev);
110 	pci_read_config_dword(pdev, AMD76X_ECC_MODE_STATUS,
111 				&info->ecc_mode_status);
112 
113 	if (info->ecc_mode_status & BIT(8))
114 		pci_write_bits32(pdev, AMD76X_ECC_MODE_STATUS,
115 				(u32) BIT(8), (u32) BIT(8));
116 
117 	if (info->ecc_mode_status & BIT(9))
118 		pci_write_bits32(pdev, AMD76X_ECC_MODE_STATUS,
119 				(u32) BIT(9), (u32) BIT(9));
120 }
121 
122 /**
123  *	amd76x_process_error_info	-	Error check
124  *	@mci: Memory controller
125  *	@info: Previously fetched information from chip
126  *	@handle_errors: 1 if we should do recovery
127  *
128  *	Process the chip state and decide if an error has occurred.
129  *	A return of 1 indicates an error. Also if handle_errors is true
130  *	then attempt to handle and clean up after the error
131  */
132 static int amd76x_process_error_info(struct mem_ctl_info *mci,
133 		struct amd76x_error_info *info, int handle_errors)
134 {
135 	int error_found;
136 	u32 row;
137 
138 	error_found = 0;
139 
140 	/*
141 	 *	Check for an uncorrectable error
142 	 */
143 	if (info->ecc_mode_status & BIT(8)) {
144 		error_found = 1;
145 
146 		if (handle_errors) {
147 			row = (info->ecc_mode_status >> 4) & 0xf;
148 			edac_mc_handle_ue(mci, mci->csrows[row].first_page, 0,
149 				row, mci->ctl_name);
150 		}
151 	}
152 
153 	/*
154 	 *	Check for a correctable error
155 	 */
156 	if (info->ecc_mode_status & BIT(9)) {
157 		error_found = 1;
158 
159 		if (handle_errors) {
160 			row = info->ecc_mode_status & 0xf;
161 			edac_mc_handle_ce(mci, mci->csrows[row].first_page, 0,
162 				0, row, 0, mci->ctl_name);
163 		}
164 	}
165 
166 	return error_found;
167 }
168 
169 /**
170  *	amd76x_check	-	Poll the controller
171  *	@mci: Memory controller
172  *
173  *	Called by the poll handlers this function reads the status
174  *	from the controller and checks for errors.
175  */
176 static void amd76x_check(struct mem_ctl_info *mci)
177 {
178 	struct amd76x_error_info info;
179 	debugf3("%s()\n", __func__);
180 	amd76x_get_error_info(mci, &info);
181 	amd76x_process_error_info(mci, &info, 1);
182 }
183 
184 static void amd76x_init_csrows(struct mem_ctl_info *mci, struct pci_dev *pdev,
185 		enum edac_type edac_mode)
186 {
187 	struct csrow_info *csrow;
188 	u32 mba, mba_base, mba_mask, dms;
189 	int index;
190 
191 	for (index = 0; index < mci->nr_csrows; index++) {
192 		csrow = &mci->csrows[index];
193 
194 		/* find the DRAM Chip Select Base address and mask */
195 		pci_read_config_dword(pdev,
196 				      AMD76X_MEM_BASE_ADDR + (index * 4),
197 				      &mba);
198 
199 		if (!(mba & BIT(0)))
200 			continue;
201 
202 		mba_base = mba & 0xff800000UL;
203 		mba_mask = ((mba & 0xff80) << 16) | 0x7fffffUL;
204 		pci_read_config_dword(pdev, AMD76X_DRAM_MODE_STATUS, &dms);
205 		csrow->first_page = mba_base >> PAGE_SHIFT;
206 		csrow->nr_pages = (mba_mask + 1) >> PAGE_SHIFT;
207 		csrow->last_page = csrow->first_page + csrow->nr_pages - 1;
208 		csrow->page_mask = mba_mask >> PAGE_SHIFT;
209 		csrow->grain = csrow->nr_pages << PAGE_SHIFT;
210 		csrow->mtype = MEM_RDDR;
211 		csrow->dtype = ((dms >> index) & 0x1) ? DEV_X4 : DEV_UNKNOWN;
212 		csrow->edac_mode = edac_mode;
213 	}
214 }
215 
216 /**
217  *	amd76x_probe1	-	Perform set up for detected device
218  *	@pdev; PCI device detected
219  *	@dev_idx: Device type index
220  *
221  *	We have found an AMD76x and now need to set up the memory
222  *	controller status reporting. We configure and set up the
223  *	memory controller reporting and claim the device.
224  */
225 static int amd76x_probe1(struct pci_dev *pdev, int dev_idx)
226 {
227 	static const enum edac_type ems_modes[] = {
228 		EDAC_NONE,
229 		EDAC_EC,
230 		EDAC_SECDED,
231 		EDAC_SECDED
232 	};
233 	struct mem_ctl_info *mci = NULL;
234 	u32 ems;
235 	u32 ems_mode;
236 	struct amd76x_error_info discard;
237 
238 	debugf0("%s()\n", __func__);
239 	pci_read_config_dword(pdev, AMD76X_ECC_MODE_STATUS, &ems);
240 	ems_mode = (ems >> 10) & 0x3;
241 	mci = edac_mc_alloc(0, AMD76X_NR_CSROWS, AMD76X_NR_CHANS);
242 
243 	if (mci == NULL) {
244 		return -ENOMEM;
245 	}
246 
247 	debugf0("%s(): mci = %p\n", __func__, mci);
248 	mci->dev = &pdev->dev;
249 	mci->mtype_cap = MEM_FLAG_RDDR;
250 	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
251 	mci->edac_cap = ems_mode ?
252 			(EDAC_FLAG_EC | EDAC_FLAG_SECDED) : EDAC_FLAG_NONE;
253 	mci->mod_name = EDAC_MOD_STR;
254 	mci->mod_ver = AMD76X_REVISION;
255 	mci->ctl_name = amd76x_devs[dev_idx].ctl_name;
256 	mci->edac_check = amd76x_check;
257 	mci->ctl_page_to_phys = NULL;
258 
259 	amd76x_init_csrows(mci, pdev, ems_modes[ems_mode]);
260 	amd76x_get_error_info(mci, &discard);  /* clear counters */
261 
262 	/* Here we assume that we will never see multiple instances of this
263 	 * type of memory controller.  The ID is therefore hardcoded to 0.
264 	 */
265 	if (edac_mc_add_mc(mci,0)) {
266 		debugf3("%s(): failed edac_mc_add_mc()\n", __func__);
267 		goto fail;
268 	}
269 
270 	/* get this far and it's successful */
271 	debugf3("%s(): success\n", __func__);
272 	return 0;
273 
274 fail:
275 	edac_mc_free(mci);
276 	return -ENODEV;
277 }
278 
279 /* returns count (>= 0), or negative on error */
280 static int __devinit amd76x_init_one(struct pci_dev *pdev,
281 		const struct pci_device_id *ent)
282 {
283 	debugf0("%s()\n", __func__);
284 
285 	/* don't need to call pci_device_enable() */
286 	return amd76x_probe1(pdev, ent->driver_data);
287 }
288 
289 /**
290  *	amd76x_remove_one	-	driver shutdown
291  *	@pdev: PCI device being handed back
292  *
293  *	Called when the driver is unloaded. Find the matching mci
294  *	structure for the device then delete the mci and free the
295  *	resources.
296  */
297 static void __devexit amd76x_remove_one(struct pci_dev *pdev)
298 {
299 	struct mem_ctl_info *mci;
300 
301 	debugf0("%s()\n", __func__);
302 
303 	if ((mci = edac_mc_del_mc(&pdev->dev)) == NULL)
304 		return;
305 
306 	edac_mc_free(mci);
307 }
308 
309 static const struct pci_device_id amd76x_pci_tbl[] __devinitdata = {
310 	{
311 		PCI_VEND_DEV(AMD, FE_GATE_700C), PCI_ANY_ID, PCI_ANY_ID, 0, 0,
312 		AMD762
313 	},
314 	{
315 		PCI_VEND_DEV(AMD, FE_GATE_700E), PCI_ANY_ID, PCI_ANY_ID, 0, 0,
316 		AMD761
317 	},
318 	{
319 		0,
320 	}	/* 0 terminated list. */
321 };
322 
323 MODULE_DEVICE_TABLE(pci, amd76x_pci_tbl);
324 
325 static struct pci_driver amd76x_driver = {
326 	.name = EDAC_MOD_STR,
327 	.probe = amd76x_init_one,
328 	.remove = __devexit_p(amd76x_remove_one),
329 	.id_table = amd76x_pci_tbl,
330 };
331 
332 static int __init amd76x_init(void)
333 {
334 	return pci_register_driver(&amd76x_driver);
335 }
336 
337 static void __exit amd76x_exit(void)
338 {
339 	pci_unregister_driver(&amd76x_driver);
340 }
341 
342 module_init(amd76x_init);
343 module_exit(amd76x_exit);
344 
345 MODULE_LICENSE("GPL");
346 MODULE_AUTHOR("Linux Networx (http://lnxi.com) Thayne Harbaugh");
347 MODULE_DESCRIPTION("MC support for AMD 76x memory controllers");
348