xref: /openbmc/linux/drivers/edac/r82600_edac.c (revision 63dc02bd)
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_core.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->dev);
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_ce(mci, page, 0,	/* not avail */
183 					syndrome,
184 					edac_mc_find_csrow_by_page(mci, page),
185 					0, mci->ctl_name);
186 	}
187 
188 	if (info->eapr & BIT(1)) {	/* UE? */
189 		error_found = 1;
190 
191 		if (handle_errors)
192 			/* 82600 doesn't give enough info */
193 			edac_mc_handle_ue(mci, page, 0,
194 					edac_mc_find_csrow_by_page(mci, page),
195 					mci->ctl_name);
196 	}
197 
198 	return error_found;
199 }
200 
201 static void r82600_check(struct mem_ctl_info *mci)
202 {
203 	struct r82600_error_info info;
204 
205 	debugf1("MC%d: %s()\n", mci->mc_idx, __func__);
206 	r82600_get_error_info(mci, &info);
207 	r82600_process_error_info(mci, &info, 1);
208 }
209 
210 static inline int ecc_enabled(u8 dramcr)
211 {
212 	return dramcr & BIT(5);
213 }
214 
215 static void r82600_init_csrows(struct mem_ctl_info *mci, struct pci_dev *pdev,
216 			u8 dramcr)
217 {
218 	struct csrow_info *csrow;
219 	int index;
220 	u8 drbar;		/* SDRAM Row Boundary Address Register */
221 	u32 row_high_limit, row_high_limit_last;
222 	u32 reg_sdram, ecc_on, row_base;
223 
224 	ecc_on = ecc_enabled(dramcr);
225 	reg_sdram = dramcr & BIT(4);
226 	row_high_limit_last = 0;
227 
228 	for (index = 0; index < mci->nr_csrows; index++) {
229 		csrow = &mci->csrows[index];
230 
231 		/* find the DRAM Chip Select Base address and mask */
232 		pci_read_config_byte(pdev, R82600_DRBA + index, &drbar);
233 
234 		debugf1("%s() Row=%d DRBA = %#0x\n", __func__, index, drbar);
235 
236 		row_high_limit = ((u32) drbar << 24);
237 /*		row_high_limit = ((u32)drbar << 24) | 0xffffffUL; */
238 
239 		debugf1("%s() Row=%d, Boundary Address=%#0x, Last = %#0x\n",
240 			__func__, index, row_high_limit, row_high_limit_last);
241 
242 		/* Empty row [p.57] */
243 		if (row_high_limit == row_high_limit_last)
244 			continue;
245 
246 		row_base = row_high_limit_last;
247 
248 		csrow->first_page = row_base >> PAGE_SHIFT;
249 		csrow->last_page = (row_high_limit >> PAGE_SHIFT) - 1;
250 		csrow->nr_pages = csrow->last_page - csrow->first_page + 1;
251 		/* Error address is top 19 bits - so granularity is      *
252 		 * 14 bits                                               */
253 		csrow->grain = 1 << 14;
254 		csrow->mtype = reg_sdram ? MEM_RDDR : MEM_DDR;
255 		/* FIXME - check that this is unknowable with this chipset */
256 		csrow->dtype = DEV_UNKNOWN;
257 
258 		/* Mode is global on 82600 */
259 		csrow->edac_mode = ecc_on ? EDAC_SECDED : EDAC_NONE;
260 		row_high_limit_last = row_high_limit;
261 	}
262 }
263 
264 static int r82600_probe1(struct pci_dev *pdev, int dev_idx)
265 {
266 	struct mem_ctl_info *mci;
267 	u8 dramcr;
268 	u32 eapr;
269 	u32 scrub_disabled;
270 	u32 sdram_refresh_rate;
271 	struct r82600_error_info discard;
272 
273 	debugf0("%s()\n", __func__);
274 	pci_read_config_byte(pdev, R82600_DRAMC, &dramcr);
275 	pci_read_config_dword(pdev, R82600_EAP, &eapr);
276 	scrub_disabled = eapr & BIT(31);
277 	sdram_refresh_rate = dramcr & (BIT(0) | BIT(1));
278 	debugf2("%s(): sdram refresh rate = %#0x\n", __func__,
279 		sdram_refresh_rate);
280 	debugf2("%s(): DRAMC register = %#0x\n", __func__, dramcr);
281 	mci = edac_mc_alloc(0, R82600_NR_CSROWS, R82600_NR_CHANS, 0);
282 
283 	if (mci == NULL)
284 		return -ENOMEM;
285 
286 	debugf0("%s(): mci = %p\n", __func__, mci);
287 	mci->dev = &pdev->dev;
288 	mci->mtype_cap = MEM_FLAG_RDDR | MEM_FLAG_DDR;
289 	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
290 	/* FIXME try to work out if the chip leads have been used for COM2
291 	 * instead on this board? [MA6?] MAYBE:
292 	 */
293 
294 	/* On the R82600, the pins for memory bits 72:65 - i.e. the   *
295 	 * EC bits are shared with the pins for COM2 (!), so if COM2  *
296 	 * is enabled, we assume COM2 is wired up, and thus no EDAC   *
297 	 * is possible.                                               */
298 	mci->edac_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
299 
300 	if (ecc_enabled(dramcr)) {
301 		if (scrub_disabled)
302 			debugf3("%s(): mci = %p - Scrubbing disabled! EAP: "
303 				"%#0x\n", __func__, mci, eapr);
304 	} else
305 		mci->edac_cap = EDAC_FLAG_NONE;
306 
307 	mci->mod_name = EDAC_MOD_STR;
308 	mci->mod_ver = R82600_REVISION;
309 	mci->ctl_name = "R82600";
310 	mci->dev_name = pci_name(pdev);
311 	mci->edac_check = r82600_check;
312 	mci->ctl_page_to_phys = NULL;
313 	r82600_init_csrows(mci, pdev, dramcr);
314 	r82600_get_error_info(mci, &discard);	/* clear counters */
315 
316 	/* Here we assume that we will never see multiple instances of this
317 	 * type of memory controller.  The ID is therefore hardcoded to 0.
318 	 */
319 	if (edac_mc_add_mc(mci)) {
320 		debugf3("%s(): failed edac_mc_add_mc()\n", __func__);
321 		goto fail;
322 	}
323 
324 	/* get this far and it's successful */
325 
326 	if (disable_hardware_scrub) {
327 		debugf3("%s(): Disabling Hardware Scrub (scrub on error)\n",
328 			__func__);
329 		pci_write_bits32(pdev, R82600_EAP, BIT(31), BIT(31));
330 	}
331 
332 	/* allocating generic PCI control info */
333 	r82600_pci = edac_pci_create_generic_ctl(&pdev->dev, EDAC_MOD_STR);
334 	if (!r82600_pci) {
335 		printk(KERN_WARNING
336 			"%s(): Unable to create PCI control\n",
337 			__func__);
338 		printk(KERN_WARNING
339 			"%s(): PCI error report via EDAC not setup\n",
340 			__func__);
341 	}
342 
343 	debugf3("%s(): success\n", __func__);
344 	return 0;
345 
346 fail:
347 	edac_mc_free(mci);
348 	return -ENODEV;
349 }
350 
351 /* returns count (>= 0), or negative on error */
352 static int __devinit r82600_init_one(struct pci_dev *pdev,
353 				const struct pci_device_id *ent)
354 {
355 	debugf0("%s()\n", __func__);
356 
357 	/* don't need to call pci_enable_device() */
358 	return r82600_probe1(pdev, ent->driver_data);
359 }
360 
361 static void __devexit r82600_remove_one(struct pci_dev *pdev)
362 {
363 	struct mem_ctl_info *mci;
364 
365 	debugf0("%s()\n", __func__);
366 
367 	if (r82600_pci)
368 		edac_pci_release_generic_ctl(r82600_pci);
369 
370 	if ((mci = edac_mc_del_mc(&pdev->dev)) == NULL)
371 		return;
372 
373 	edac_mc_free(mci);
374 }
375 
376 static DEFINE_PCI_DEVICE_TABLE(r82600_pci_tbl) = {
377 	{
378 	 PCI_DEVICE(PCI_VENDOR_ID_RADISYS, R82600_BRIDGE_ID)
379 	 },
380 	{
381 	 0,
382 	 }			/* 0 terminated list. */
383 };
384 
385 MODULE_DEVICE_TABLE(pci, r82600_pci_tbl);
386 
387 static struct pci_driver r82600_driver = {
388 	.name = EDAC_MOD_STR,
389 	.probe = r82600_init_one,
390 	.remove = __devexit_p(r82600_remove_one),
391 	.id_table = r82600_pci_tbl,
392 };
393 
394 static int __init r82600_init(void)
395 {
396        /* Ensure that the OPSTATE is set correctly for POLL or NMI */
397        opstate_init();
398 
399 	return pci_register_driver(&r82600_driver);
400 }
401 
402 static void __exit r82600_exit(void)
403 {
404 	pci_unregister_driver(&r82600_driver);
405 }
406 
407 module_init(r82600_init);
408 module_exit(r82600_exit);
409 
410 MODULE_LICENSE("GPL");
411 MODULE_AUTHOR("Tim Small <tim@buttersideup.com> - WPAD Ltd. "
412 		"on behalf of EADS Astrium");
413 MODULE_DESCRIPTION("MC support for Radisys 82600 memory controllers");
414 
415 module_param(disable_hardware_scrub, bool, 0644);
416 MODULE_PARM_DESC(disable_hardware_scrub,
417 		 "If set, disable the chipset's automatic scrub for CEs");
418 
419 module_param(edac_op_state, int, 0444);
420 MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");
421