xref: /openbmc/linux/drivers/edac/r82600_edac.c (revision fd589a8f)
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/slab.h>
23 #include <linux/edac.h>
24 #include "edac_core.h"
25 
26 #define R82600_REVISION	" Ver: 2.0.2 " __DATE__
27 #define EDAC_MOD_STR	"r82600_edac"
28 
29 #define r82600_printk(level, fmt, arg...) \
30 	edac_printk(level, "r82600", fmt, ##arg)
31 
32 #define r82600_mc_printk(mci, level, fmt, arg...) \
33 	edac_mc_chipset_printk(mci, level, "r82600", fmt, ##arg)
34 
35 /* Radisys say "The 82600 integrates a main memory SDRAM controller that
36  * supports up to four banks of memory. The four banks can support a mix of
37  * sizes of 64 bit wide (72 bits with ECC) Synchronous DRAM (SDRAM) DIMMs,
38  * each of which can be any size from 16MB to 512MB. Both registered (control
39  * signals buffered) and unbuffered DIMM types are supported. Mixing of
40  * registered and unbuffered DIMMs as well as mixing of ECC and non-ECC DIMMs
41  * is not allowed. The 82600 SDRAM interface operates at the same frequency as
42  * the CPU bus, 66MHz, 100MHz or 133MHz."
43  */
44 
45 #define R82600_NR_CSROWS 4
46 #define R82600_NR_CHANS  1
47 #define R82600_NR_DIMMS  4
48 
49 #define R82600_BRIDGE_ID  0x8200
50 
51 /* Radisys 82600 register addresses - device 0 function 0 - PCI bridge */
52 #define R82600_DRAMC	0x57	/* Various SDRAM related control bits
53 				 * all bits are R/W
54 				 *
55 				 * 7    SDRAM ISA Hole Enable
56 				 * 6    Flash Page Mode Enable
57 				 * 5    ECC Enable: 1=ECC 0=noECC
58 				 * 4    DRAM DIMM Type: 1=
59 				 * 3    BIOS Alias Disable
60 				 * 2    SDRAM BIOS Flash Write Enable
61 				 * 1:0  SDRAM Refresh Rate: 00=Disabled
62 				 *          01=7.8usec (256Mbit SDRAMs)
63 				 *          10=15.6us 11=125usec
64 				 */
65 
66 #define R82600_SDRAMC	0x76	/* "SDRAM Control Register"
67 				 * More SDRAM related control bits
68 				 * all bits are R/W
69 				 *
70 				 * 15:8 Reserved.
71 				 *
72 				 * 7:5  Special SDRAM Mode Select
73 				 *
74 				 * 4    Force ECC
75 				 *
76 				 *        1=Drive ECC bits to 0 during
77 				 *          write cycles (i.e. ECC test mode)
78 				 *
79 				 *        0=Normal ECC functioning
80 				 *
81 				 * 3    Enhanced Paging Enable
82 				 *
83 				 * 2    CAS# Latency 0=3clks 1=2clks
84 				 *
85 				 * 1    RAS# to CAS# Delay 0=3 1=2
86 				 *
87 				 * 0    RAS# Precharge     0=3 1=2
88 				 */
89 
90 #define R82600_EAP	0x80	/* ECC Error Address Pointer Register
91 				 *
92 				 * 31    Disable Hardware Scrubbing (RW)
93 				 *        0=Scrub on corrected read
94 				 *        1=Don't scrub on corrected read
95 				 *
96 				 * 30:12 Error Address Pointer (RO)
97 				 *        Upper 19 bits of error address
98 				 *
99 				 * 11:4  Syndrome Bits (RO)
100 				 *
101 				 * 3     BSERR# on multibit error (RW)
102 				 *        1=enable 0=disable
103 				 *
104 				 * 2     NMI on Single Bit Eror (RW)
105 				 *        1=NMI triggered by SBE n.b. other
106 				 *          prerequeists
107 				 *        0=NMI not triggered
108 				 *
109 				 * 1     MBE (R/WC)
110 				 *        read 1=MBE at EAP (see above)
111 				 *        read 0=no MBE, or SBE occurred first
112 				 *        write 1=Clear MBE status (must also
113 				 *          clear SBE)
114 				 *        write 0=NOP
115 				 *
116 				 * 1     SBE (R/WC)
117 				 *        read 1=SBE at EAP (see above)
118 				 *        read 0=no SBE, or MBE occurred first
119 				 *        write 1=Clear SBE status (must also
120 				 *          clear MBE)
121 				 *        write 0=NOP
122 				 */
123 
124 #define R82600_DRBA	0x60	/* + 0x60..0x63 SDRAM Row Boundry Address
125 				 *  Registers
126 				 *
127 				 * 7:0  Address lines 30:24 - upper limit of
128 				 * each row [p57]
129 				 */
130 
131 struct r82600_error_info {
132 	u32 eapr;
133 };
134 
135 static unsigned int disable_hardware_scrub;
136 
137 static struct edac_pci_ctl_info *r82600_pci;
138 
139 static void r82600_get_error_info(struct mem_ctl_info *mci,
140 				struct r82600_error_info *info)
141 {
142 	struct pci_dev *pdev;
143 
144 	pdev = to_pci_dev(mci->dev);
145 	pci_read_config_dword(pdev, R82600_EAP, &info->eapr);
146 
147 	if (info->eapr & BIT(0))
148 		/* Clear error to allow next error to be reported [p.62] */
149 		pci_write_bits32(pdev, R82600_EAP,
150 				 ((u32) BIT(0) & (u32) BIT(1)),
151 				 ((u32) BIT(0) & (u32) BIT(1)));
152 
153 	if (info->eapr & BIT(1))
154 		/* Clear error to allow next error to be reported [p.62] */
155 		pci_write_bits32(pdev, R82600_EAP,
156 				 ((u32) BIT(0) & (u32) BIT(1)),
157 				 ((u32) BIT(0) & (u32) BIT(1)));
158 }
159 
160 static int r82600_process_error_info(struct mem_ctl_info *mci,
161 				struct r82600_error_info *info,
162 				int handle_errors)
163 {
164 	int error_found;
165 	u32 eapaddr, page;
166 	u32 syndrome;
167 
168 	error_found = 0;
169 
170 	/* bits 30:12 store the upper 19 bits of the 32 bit error address */
171 	eapaddr = ((info->eapr >> 12) & 0x7FFF) << 13;
172 	/* Syndrome in bits 11:4 [p.62]       */
173 	syndrome = (info->eapr >> 4) & 0xFF;
174 
175 	/* the R82600 reports at less than page *
176 	 * granularity (upper 19 bits only)     */
177 	page = eapaddr >> PAGE_SHIFT;
178 
179 	if (info->eapr & BIT(0)) {	/* CE? */
180 		error_found = 1;
181 
182 		if (handle_errors)
183 			edac_mc_handle_ce(mci, page, 0,	/* not avail */
184 					syndrome,
185 					edac_mc_find_csrow_by_page(mci, page),
186 					0, 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_ue(mci, page, 0,
195 					edac_mc_find_csrow_by_page(mci, page),
196 					mci->ctl_name);
197 	}
198 
199 	return error_found;
200 }
201 
202 static void r82600_check(struct mem_ctl_info *mci)
203 {
204 	struct r82600_error_info info;
205 
206 	debugf1("MC%d: %s()\n", mci->mc_idx, __func__);
207 	r82600_get_error_info(mci, &info);
208 	r82600_process_error_info(mci, &info, 1);
209 }
210 
211 static inline int ecc_enabled(u8 dramcr)
212 {
213 	return dramcr & BIT(5);
214 }
215 
216 static void r82600_init_csrows(struct mem_ctl_info *mci, struct pci_dev *pdev,
217 			u8 dramcr)
218 {
219 	struct csrow_info *csrow;
220 	int index;
221 	u8 drbar;		/* SDRAM Row Boundry Address Register */
222 	u32 row_high_limit, row_high_limit_last;
223 	u32 reg_sdram, ecc_on, row_base;
224 
225 	ecc_on = ecc_enabled(dramcr);
226 	reg_sdram = dramcr & BIT(4);
227 	row_high_limit_last = 0;
228 
229 	for (index = 0; index < mci->nr_csrows; index++) {
230 		csrow = &mci->csrows[index];
231 
232 		/* find the DRAM Chip Select Base address and mask */
233 		pci_read_config_byte(pdev, R82600_DRBA + index, &drbar);
234 
235 		debugf1("%s() Row=%d DRBA = %#0x\n", __func__, index, drbar);
236 
237 		row_high_limit = ((u32) drbar << 24);
238 /*		row_high_limit = ((u32)drbar << 24) | 0xffffffUL; */
239 
240 		debugf1("%s() Row=%d, Boundry Address=%#0x, Last = %#0x\n",
241 			__func__, index, row_high_limit, row_high_limit_last);
242 
243 		/* Empty row [p.57] */
244 		if (row_high_limit == row_high_limit_last)
245 			continue;
246 
247 		row_base = row_high_limit_last;
248 
249 		csrow->first_page = row_base >> PAGE_SHIFT;
250 		csrow->last_page = (row_high_limit >> PAGE_SHIFT) - 1;
251 		csrow->nr_pages = csrow->last_page - csrow->first_page + 1;
252 		/* Error address is top 19 bits - so granularity is      *
253 		 * 14 bits                                               */
254 		csrow->grain = 1 << 14;
255 		csrow->mtype = reg_sdram ? MEM_RDDR : MEM_DDR;
256 		/* FIXME - check that this is unknowable with this chipset */
257 		csrow->dtype = DEV_UNKNOWN;
258 
259 		/* Mode is global on 82600 */
260 		csrow->edac_mode = ecc_on ? EDAC_SECDED : EDAC_NONE;
261 		row_high_limit_last = row_high_limit;
262 	}
263 }
264 
265 static int r82600_probe1(struct pci_dev *pdev, int dev_idx)
266 {
267 	struct mem_ctl_info *mci;
268 	u8 dramcr;
269 	u32 eapr;
270 	u32 scrub_disabled;
271 	u32 sdram_refresh_rate;
272 	struct r82600_error_info discard;
273 
274 	debugf0("%s()\n", __func__);
275 	pci_read_config_byte(pdev, R82600_DRAMC, &dramcr);
276 	pci_read_config_dword(pdev, R82600_EAP, &eapr);
277 	scrub_disabled = eapr & BIT(31);
278 	sdram_refresh_rate = dramcr & (BIT(0) | BIT(1));
279 	debugf2("%s(): sdram refresh rate = %#0x\n", __func__,
280 		sdram_refresh_rate);
281 	debugf2("%s(): DRAMC register = %#0x\n", __func__, dramcr);
282 	mci = edac_mc_alloc(0, R82600_NR_CSROWS, R82600_NR_CHANS, 0);
283 
284 	if (mci == NULL)
285 		return -ENOMEM;
286 
287 	debugf0("%s(): mci = %p\n", __func__, mci);
288 	mci->dev = &pdev->dev;
289 	mci->mtype_cap = MEM_FLAG_RDDR | MEM_FLAG_DDR;
290 	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
291 	/* FIXME try to work out if the chip leads have been used for COM2
292 	 * instead on this board? [MA6?] MAYBE:
293 	 */
294 
295 	/* On the R82600, the pins for memory bits 72:65 - i.e. the   *
296 	 * EC bits are shared with the pins for COM2 (!), so if COM2  *
297 	 * is enabled, we assume COM2 is wired up, and thus no EDAC   *
298 	 * is possible.                                               */
299 	mci->edac_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
300 
301 	if (ecc_enabled(dramcr)) {
302 		if (scrub_disabled)
303 			debugf3("%s(): mci = %p - Scrubbing disabled! EAP: "
304 				"%#0x\n", __func__, mci, eapr);
305 	} else
306 		mci->edac_cap = EDAC_FLAG_NONE;
307 
308 	mci->mod_name = EDAC_MOD_STR;
309 	mci->mod_ver = R82600_REVISION;
310 	mci->ctl_name = "R82600";
311 	mci->dev_name = pci_name(pdev);
312 	mci->edac_check = r82600_check;
313 	mci->ctl_page_to_phys = NULL;
314 	r82600_init_csrows(mci, pdev, dramcr);
315 	r82600_get_error_info(mci, &discard);	/* clear counters */
316 
317 	/* Here we assume that we will never see multiple instances of this
318 	 * type of memory controller.  The ID is therefore hardcoded to 0.
319 	 */
320 	if (edac_mc_add_mc(mci)) {
321 		debugf3("%s(): failed edac_mc_add_mc()\n", __func__);
322 		goto fail;
323 	}
324 
325 	/* get this far and it's successful */
326 
327 	if (disable_hardware_scrub) {
328 		debugf3("%s(): Disabling Hardware Scrub (scrub on error)\n",
329 			__func__);
330 		pci_write_bits32(pdev, R82600_EAP, BIT(31), BIT(31));
331 	}
332 
333 	/* allocating generic PCI control info */
334 	r82600_pci = edac_pci_create_generic_ctl(&pdev->dev, EDAC_MOD_STR);
335 	if (!r82600_pci) {
336 		printk(KERN_WARNING
337 			"%s(): Unable to create PCI control\n",
338 			__func__);
339 		printk(KERN_WARNING
340 			"%s(): PCI error report via EDAC not setup\n",
341 			__func__);
342 	}
343 
344 	debugf3("%s(): success\n", __func__);
345 	return 0;
346 
347 fail:
348 	edac_mc_free(mci);
349 	return -ENODEV;
350 }
351 
352 /* returns count (>= 0), or negative on error */
353 static int __devinit r82600_init_one(struct pci_dev *pdev,
354 				const struct pci_device_id *ent)
355 {
356 	debugf0("%s()\n", __func__);
357 
358 	/* don't need to call pci_device_enable() */
359 	return r82600_probe1(pdev, ent->driver_data);
360 }
361 
362 static void __devexit r82600_remove_one(struct pci_dev *pdev)
363 {
364 	struct mem_ctl_info *mci;
365 
366 	debugf0("%s()\n", __func__);
367 
368 	if (r82600_pci)
369 		edac_pci_release_generic_ctl(r82600_pci);
370 
371 	if ((mci = edac_mc_del_mc(&pdev->dev)) == NULL)
372 		return;
373 
374 	edac_mc_free(mci);
375 }
376 
377 static const struct pci_device_id r82600_pci_tbl[] __devinitdata = {
378 	{
379 	 PCI_DEVICE(PCI_VENDOR_ID_RADISYS, R82600_BRIDGE_ID)
380 	 },
381 	{
382 	 0,
383 	 }			/* 0 terminated list. */
384 };
385 
386 MODULE_DEVICE_TABLE(pci, r82600_pci_tbl);
387 
388 static struct pci_driver r82600_driver = {
389 	.name = EDAC_MOD_STR,
390 	.probe = r82600_init_one,
391 	.remove = __devexit_p(r82600_remove_one),
392 	.id_table = r82600_pci_tbl,
393 };
394 
395 static int __init r82600_init(void)
396 {
397        /* Ensure that the OPSTATE is set correctly for POLL or NMI */
398        opstate_init();
399 
400 	return pci_register_driver(&r82600_driver);
401 }
402 
403 static void __exit r82600_exit(void)
404 {
405 	pci_unregister_driver(&r82600_driver);
406 }
407 
408 module_init(r82600_init);
409 module_exit(r82600_exit);
410 
411 MODULE_LICENSE("GPL");
412 MODULE_AUTHOR("Tim Small <tim@buttersideup.com> - WPAD Ltd. "
413 		"on behalf of EADS Astrium");
414 MODULE_DESCRIPTION("MC support for Radisys 82600 memory controllers");
415 
416 module_param(disable_hardware_scrub, bool, 0644);
417 MODULE_PARM_DESC(disable_hardware_scrub,
418 		 "If set, disable the chipset's automatic scrub for CEs");
419 
420 module_param(edac_op_state, int, 0444);
421 MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");
422