xref: /openbmc/linux/drivers/edac/r82600_edac.c (revision dea54fba)
1 /*
2  * Radisys 82600 Embedded chipset Memory Controller kernel module
3  * (C) 2005 EADS Astrium
4  * This file may be distributed under the terms of the
5  * GNU General Public License.
6  *
7  * Written by Tim Small <tim@buttersideup.com>, based on work by Thayne
8  * Harbaugh, Dan Hollis <goemon at anime dot net> and others.
9  *
10  * $Id: edac_r82600.c,v 1.1.2.6 2005/10/05 00:43:44 dsp_llnl Exp $
11  *
12  * Written with reference to 82600 High Integration Dual PCI System
13  * Controller Data Book:
14  * www.radisys.com/files/support_downloads/007-01277-0002.82600DataBook.pdf
15  * references to this document given in []
16  */
17 
18 #include <linux/module.h>
19 #include <linux/init.h>
20 #include <linux/pci.h>
21 #include <linux/pci_ids.h>
22 #include <linux/edac.h>
23 #include "edac_module.h"
24 
25 #define R82600_REVISION	" Ver: 2.0.2"
26 #define EDAC_MOD_STR	"r82600_edac"
27 
28 #define r82600_printk(level, fmt, arg...) \
29 	edac_printk(level, "r82600", fmt, ##arg)
30 
31 #define r82600_mc_printk(mci, level, fmt, arg...) \
32 	edac_mc_chipset_printk(mci, level, "r82600", fmt, ##arg)
33 
34 /* Radisys say "The 82600 integrates a main memory SDRAM controller that
35  * supports up to four banks of memory. The four banks can support a mix of
36  * sizes of 64 bit wide (72 bits with ECC) Synchronous DRAM (SDRAM) DIMMs,
37  * each of which can be any size from 16MB to 512MB. Both registered (control
38  * signals buffered) and unbuffered DIMM types are supported. Mixing of
39  * registered and unbuffered DIMMs as well as mixing of ECC and non-ECC DIMMs
40  * is not allowed. The 82600 SDRAM interface operates at the same frequency as
41  * the CPU bus, 66MHz, 100MHz or 133MHz."
42  */
43 
44 #define R82600_NR_CSROWS 4
45 #define R82600_NR_CHANS  1
46 #define R82600_NR_DIMMS  4
47 
48 #define R82600_BRIDGE_ID  0x8200
49 
50 /* Radisys 82600 register addresses - device 0 function 0 - PCI bridge */
51 #define R82600_DRAMC	0x57	/* Various SDRAM related control bits
52 				 * all bits are R/W
53 				 *
54 				 * 7    SDRAM ISA Hole Enable
55 				 * 6    Flash Page Mode Enable
56 				 * 5    ECC Enable: 1=ECC 0=noECC
57 				 * 4    DRAM DIMM Type: 1=
58 				 * 3    BIOS Alias Disable
59 				 * 2    SDRAM BIOS Flash Write Enable
60 				 * 1:0  SDRAM Refresh Rate: 00=Disabled
61 				 *          01=7.8usec (256Mbit SDRAMs)
62 				 *          10=15.6us 11=125usec
63 				 */
64 
65 #define R82600_SDRAMC	0x76	/* "SDRAM Control Register"
66 				 * More SDRAM related control bits
67 				 * all bits are R/W
68 				 *
69 				 * 15:8 Reserved.
70 				 *
71 				 * 7:5  Special SDRAM Mode Select
72 				 *
73 				 * 4    Force ECC
74 				 *
75 				 *        1=Drive ECC bits to 0 during
76 				 *          write cycles (i.e. ECC test mode)
77 				 *
78 				 *        0=Normal ECC functioning
79 				 *
80 				 * 3    Enhanced Paging Enable
81 				 *
82 				 * 2    CAS# Latency 0=3clks 1=2clks
83 				 *
84 				 * 1    RAS# to CAS# Delay 0=3 1=2
85 				 *
86 				 * 0    RAS# Precharge     0=3 1=2
87 				 */
88 
89 #define R82600_EAP	0x80	/* ECC Error Address Pointer Register
90 				 *
91 				 * 31    Disable Hardware Scrubbing (RW)
92 				 *        0=Scrub on corrected read
93 				 *        1=Don't scrub on corrected read
94 				 *
95 				 * 30:12 Error Address Pointer (RO)
96 				 *        Upper 19 bits of error address
97 				 *
98 				 * 11:4  Syndrome Bits (RO)
99 				 *
100 				 * 3     BSERR# on multibit error (RW)
101 				 *        1=enable 0=disable
102 				 *
103 				 * 2     NMI on Single Bit Eror (RW)
104 				 *        1=NMI triggered by SBE n.b. other
105 				 *          prerequeists
106 				 *        0=NMI not triggered
107 				 *
108 				 * 1     MBE (R/WC)
109 				 *        read 1=MBE at EAP (see above)
110 				 *        read 0=no MBE, or SBE occurred first
111 				 *        write 1=Clear MBE status (must also
112 				 *          clear SBE)
113 				 *        write 0=NOP
114 				 *
115 				 * 1     SBE (R/WC)
116 				 *        read 1=SBE at EAP (see above)
117 				 *        read 0=no SBE, or MBE occurred first
118 				 *        write 1=Clear SBE status (must also
119 				 *          clear MBE)
120 				 *        write 0=NOP
121 				 */
122 
123 #define R82600_DRBA	0x60	/* + 0x60..0x63 SDRAM Row Boundary Address
124 				 *  Registers
125 				 *
126 				 * 7:0  Address lines 30:24 - upper limit of
127 				 * each row [p57]
128 				 */
129 
130 struct r82600_error_info {
131 	u32 eapr;
132 };
133 
134 static bool disable_hardware_scrub;
135 
136 static struct edac_pci_ctl_info *r82600_pci;
137 
138 static void r82600_get_error_info(struct mem_ctl_info *mci,
139 				struct r82600_error_info *info)
140 {
141 	struct pci_dev *pdev;
142 
143 	pdev = to_pci_dev(mci->pdev);
144 	pci_read_config_dword(pdev, R82600_EAP, &info->eapr);
145 
146 	if (info->eapr & BIT(0))
147 		/* Clear error to allow next error to be reported [p.62] */
148 		pci_write_bits32(pdev, R82600_EAP,
149 				 ((u32) BIT(0) & (u32) BIT(1)),
150 				 ((u32) BIT(0) & (u32) BIT(1)));
151 
152 	if (info->eapr & BIT(1))
153 		/* Clear error to allow next error to be reported [p.62] */
154 		pci_write_bits32(pdev, R82600_EAP,
155 				 ((u32) BIT(0) & (u32) BIT(1)),
156 				 ((u32) BIT(0) & (u32) BIT(1)));
157 }
158 
159 static int r82600_process_error_info(struct mem_ctl_info *mci,
160 				struct r82600_error_info *info,
161 				int handle_errors)
162 {
163 	int error_found;
164 	u32 eapaddr, page;
165 	u32 syndrome;
166 
167 	error_found = 0;
168 
169 	/* bits 30:12 store the upper 19 bits of the 32 bit error address */
170 	eapaddr = ((info->eapr >> 12) & 0x7FFF) << 13;
171 	/* Syndrome in bits 11:4 [p.62]       */
172 	syndrome = (info->eapr >> 4) & 0xFF;
173 
174 	/* the R82600 reports at less than page *
175 	 * granularity (upper 19 bits only)     */
176 	page = eapaddr >> PAGE_SHIFT;
177 
178 	if (info->eapr & BIT(0)) {	/* CE? */
179 		error_found = 1;
180 
181 		if (handle_errors)
182 			edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, 1,
183 					     page, 0, syndrome,
184 					     edac_mc_find_csrow_by_page(mci, page),
185 					     0, -1,
186 					     mci->ctl_name, "");
187 	}
188 
189 	if (info->eapr & BIT(1)) {	/* UE? */
190 		error_found = 1;
191 
192 		if (handle_errors)
193 			/* 82600 doesn't give enough info */
194 			edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 1,
195 					     page, 0, 0,
196 					     edac_mc_find_csrow_by_page(mci, page),
197 					     0, -1,
198 					     mci->ctl_name, "");
199 	}
200 
201 	return error_found;
202 }
203 
204 static void r82600_check(struct mem_ctl_info *mci)
205 {
206 	struct r82600_error_info info;
207 
208 	edac_dbg(1, "MC%d\n", mci->mc_idx);
209 	r82600_get_error_info(mci, &info);
210 	r82600_process_error_info(mci, &info, 1);
211 }
212 
213 static inline int ecc_enabled(u8 dramcr)
214 {
215 	return dramcr & BIT(5);
216 }
217 
218 static void r82600_init_csrows(struct mem_ctl_info *mci, struct pci_dev *pdev,
219 			u8 dramcr)
220 {
221 	struct csrow_info *csrow;
222 	struct dimm_info *dimm;
223 	int index;
224 	u8 drbar;		/* SDRAM Row Boundary Address Register */
225 	u32 row_high_limit, row_high_limit_last;
226 	u32 reg_sdram, ecc_on, row_base;
227 
228 	ecc_on = ecc_enabled(dramcr);
229 	reg_sdram = dramcr & BIT(4);
230 	row_high_limit_last = 0;
231 
232 	for (index = 0; index < mci->nr_csrows; index++) {
233 		csrow = mci->csrows[index];
234 		dimm = csrow->channels[0]->dimm;
235 
236 		/* find the DRAM Chip Select Base address and mask */
237 		pci_read_config_byte(pdev, R82600_DRBA + index, &drbar);
238 
239 		edac_dbg(1, "Row=%d DRBA = %#0x\n", index, drbar);
240 
241 		row_high_limit = ((u32) drbar << 24);
242 /*		row_high_limit = ((u32)drbar << 24) | 0xffffffUL; */
243 
244 		edac_dbg(1, "Row=%d, Boundary Address=%#0x, Last = %#0x\n",
245 			 index, row_high_limit, row_high_limit_last);
246 
247 		/* Empty row [p.57] */
248 		if (row_high_limit == row_high_limit_last)
249 			continue;
250 
251 		row_base = row_high_limit_last;
252 
253 		csrow->first_page = row_base >> PAGE_SHIFT;
254 		csrow->last_page = (row_high_limit >> PAGE_SHIFT) - 1;
255 
256 		dimm->nr_pages = csrow->last_page - csrow->first_page + 1;
257 		/* Error address is top 19 bits - so granularity is      *
258 		 * 14 bits                                               */
259 		dimm->grain = 1 << 14;
260 		dimm->mtype = reg_sdram ? MEM_RDDR : MEM_DDR;
261 		/* FIXME - check that this is unknowable with this chipset */
262 		dimm->dtype = DEV_UNKNOWN;
263 
264 		/* Mode is global on 82600 */
265 		dimm->edac_mode = ecc_on ? EDAC_SECDED : EDAC_NONE;
266 		row_high_limit_last = row_high_limit;
267 	}
268 }
269 
270 static int r82600_probe1(struct pci_dev *pdev, int dev_idx)
271 {
272 	struct mem_ctl_info *mci;
273 	struct edac_mc_layer layers[2];
274 	u8 dramcr;
275 	u32 eapr;
276 	u32 scrub_disabled;
277 	u32 sdram_refresh_rate;
278 	struct r82600_error_info discard;
279 
280 	edac_dbg(0, "\n");
281 	pci_read_config_byte(pdev, R82600_DRAMC, &dramcr);
282 	pci_read_config_dword(pdev, R82600_EAP, &eapr);
283 	scrub_disabled = eapr & BIT(31);
284 	sdram_refresh_rate = dramcr & (BIT(0) | BIT(1));
285 	edac_dbg(2, "sdram refresh rate = %#0x\n", sdram_refresh_rate);
286 	edac_dbg(2, "DRAMC register = %#0x\n", dramcr);
287 	layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
288 	layers[0].size = R82600_NR_CSROWS;
289 	layers[0].is_virt_csrow = true;
290 	layers[1].type = EDAC_MC_LAYER_CHANNEL;
291 	layers[1].size = R82600_NR_CHANS;
292 	layers[1].is_virt_csrow = false;
293 	mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers, 0);
294 	if (mci == NULL)
295 		return -ENOMEM;
296 
297 	edac_dbg(0, "mci = %p\n", mci);
298 	mci->pdev = &pdev->dev;
299 	mci->mtype_cap = MEM_FLAG_RDDR | MEM_FLAG_DDR;
300 	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
301 	/* FIXME try to work out if the chip leads have been used for COM2
302 	 * instead on this board? [MA6?] MAYBE:
303 	 */
304 
305 	/* On the R82600, the pins for memory bits 72:65 - i.e. the   *
306 	 * EC bits are shared with the pins for COM2 (!), so if COM2  *
307 	 * is enabled, we assume COM2 is wired up, and thus no EDAC   *
308 	 * is possible.                                               */
309 	mci->edac_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
310 
311 	if (ecc_enabled(dramcr)) {
312 		if (scrub_disabled)
313 			edac_dbg(3, "mci = %p - Scrubbing disabled! EAP: %#0x\n",
314 				 mci, eapr);
315 	} else
316 		mci->edac_cap = EDAC_FLAG_NONE;
317 
318 	mci->mod_name = EDAC_MOD_STR;
319 	mci->mod_ver = R82600_REVISION;
320 	mci->ctl_name = "R82600";
321 	mci->dev_name = pci_name(pdev);
322 	mci->edac_check = r82600_check;
323 	mci->ctl_page_to_phys = NULL;
324 	r82600_init_csrows(mci, pdev, dramcr);
325 	r82600_get_error_info(mci, &discard);	/* clear counters */
326 
327 	/* Here we assume that we will never see multiple instances of this
328 	 * type of memory controller.  The ID is therefore hardcoded to 0.
329 	 */
330 	if (edac_mc_add_mc(mci)) {
331 		edac_dbg(3, "failed edac_mc_add_mc()\n");
332 		goto fail;
333 	}
334 
335 	/* get this far and it's successful */
336 
337 	if (disable_hardware_scrub) {
338 		edac_dbg(3, "Disabling Hardware Scrub (scrub on error)\n");
339 		pci_write_bits32(pdev, R82600_EAP, BIT(31), BIT(31));
340 	}
341 
342 	/* allocating generic PCI control info */
343 	r82600_pci = edac_pci_create_generic_ctl(&pdev->dev, EDAC_MOD_STR);
344 	if (!r82600_pci) {
345 		printk(KERN_WARNING
346 			"%s(): Unable to create PCI control\n",
347 			__func__);
348 		printk(KERN_WARNING
349 			"%s(): PCI error report via EDAC not setup\n",
350 			__func__);
351 	}
352 
353 	edac_dbg(3, "success\n");
354 	return 0;
355 
356 fail:
357 	edac_mc_free(mci);
358 	return -ENODEV;
359 }
360 
361 /* returns count (>= 0), or negative on error */
362 static int r82600_init_one(struct pci_dev *pdev,
363 			   const struct pci_device_id *ent)
364 {
365 	edac_dbg(0, "\n");
366 
367 	/* don't need to call pci_enable_device() */
368 	return r82600_probe1(pdev, ent->driver_data);
369 }
370 
371 static void r82600_remove_one(struct pci_dev *pdev)
372 {
373 	struct mem_ctl_info *mci;
374 
375 	edac_dbg(0, "\n");
376 
377 	if (r82600_pci)
378 		edac_pci_release_generic_ctl(r82600_pci);
379 
380 	if ((mci = edac_mc_del_mc(&pdev->dev)) == NULL)
381 		return;
382 
383 	edac_mc_free(mci);
384 }
385 
386 static const struct pci_device_id r82600_pci_tbl[] = {
387 	{
388 	 PCI_DEVICE(PCI_VENDOR_ID_RADISYS, R82600_BRIDGE_ID)
389 	 },
390 	{
391 	 0,
392 	 }			/* 0 terminated list. */
393 };
394 
395 MODULE_DEVICE_TABLE(pci, r82600_pci_tbl);
396 
397 static struct pci_driver r82600_driver = {
398 	.name = EDAC_MOD_STR,
399 	.probe = r82600_init_one,
400 	.remove = r82600_remove_one,
401 	.id_table = r82600_pci_tbl,
402 };
403 
404 static int __init r82600_init(void)
405 {
406        /* Ensure that the OPSTATE is set correctly for POLL or NMI */
407        opstate_init();
408 
409 	return pci_register_driver(&r82600_driver);
410 }
411 
412 static void __exit r82600_exit(void)
413 {
414 	pci_unregister_driver(&r82600_driver);
415 }
416 
417 module_init(r82600_init);
418 module_exit(r82600_exit);
419 
420 MODULE_LICENSE("GPL");
421 MODULE_AUTHOR("Tim Small <tim@buttersideup.com> - WPAD Ltd. "
422 		"on behalf of EADS Astrium");
423 MODULE_DESCRIPTION("MC support for Radisys 82600 memory controllers");
424 
425 module_param(disable_hardware_scrub, bool, 0644);
426 MODULE_PARM_DESC(disable_hardware_scrub,
427 		 "If set, disable the chipset's automatic scrub for CEs");
428 
429 module_param(edac_op_state, int, 0444);
430 MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");
431