Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm
[linux-2.6] / drivers / edac / r82600_edac.c
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 "edac_core.h"
24
25 #define R82600_REVISION " Ver: 2.0.2 " __DATE__
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 Boundry 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 unsigned int 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 Boundry 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, Boundry 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_device_enable() */
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 const struct pci_device_id r82600_pci_tbl[] __devinitdata = {
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         return pci_register_driver(&r82600_driver);
397 }
398
399 static void __exit r82600_exit(void)
400 {
401         pci_unregister_driver(&r82600_driver);
402 }
403
404 module_init(r82600_init);
405 module_exit(r82600_exit);
406
407 MODULE_LICENSE("GPL");
408 MODULE_AUTHOR("Tim Small <tim@buttersideup.com> - WPAD Ltd. "
409                 "on behalf of EADS Astrium");
410 MODULE_DESCRIPTION("MC support for Radisys 82600 memory controllers");
411
412 module_param(disable_hardware_scrub, bool, 0644);
413 MODULE_PARM_DESC(disable_hardware_scrub,
414                  "If set, disable the chipset's automatic scrub for CEs");