1/*
2 * Intel X38 Memory Controller kernel module
3 * Copyright (C) 2008 Cluster Computing, Inc.
4 *
5 * This file may be distributed under the terms of the
6 * GNU General Public License.
7 *
8 * This file is based on i3200_edac.c
9 *
10 */
11
12#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/pci.h>
15#include <linux/pci_ids.h>
16#include <linux/edac.h>
17
18#include <linux/io-64-nonatomic-lo-hi.h>
19#include "edac_module.h"
20
21#define EDAC_MOD_STR "x38_edac"
22
23#define PCI_DEVICE_ID_INTEL_X38_HB 0x29e0
24
25#define X38_RANKS 8
26#define X38_RANKS_PER_CHANNEL 4
27#define X38_CHANNELS 2
28
29/* Intel X38 register addresses - device 0 function 0 - DRAM Controller */
30
31#define X38_MCHBAR_LOW 0x48 /* MCH Memory Mapped Register BAR */
32#define X38_MCHBAR_HIGH 0x4c
33#define X38_MCHBAR_MASK 0xfffffc000ULL /* bits 35:14 */
34#define X38_MMR_WINDOW_SIZE 16384
35
36#define X38_TOM 0xa0 /* Top of Memory (16b)
37 *
38 * 15:10 reserved
39 * 9:0 total populated physical memory
40 */
41#define X38_TOM_MASK 0x3ff /* bits 9:0 */
42#define X38_TOM_SHIFT 26 /* 64MiB grain */
43
44#define X38_ERRSTS 0xc8 /* Error Status Register (16b)
45 *
46 * 15 reserved
47 * 14 Isochronous TBWRR Run Behind FIFO Full
48 * (ITCV)
49 * 13 Isochronous TBWRR Run Behind FIFO Put
50 * (ITSTV)
51 * 12 reserved
52 * 11 MCH Thermal Sensor Event
53 * for SMI/SCI/SERR (GTSE)
54 * 10 reserved
55 * 9 LOCK to non-DRAM Memory Flag (LCKF)
56 * 8 reserved
57 * 7 DRAM Throttle Flag (DTF)
58 * 6:2 reserved
59 * 1 Multi-bit DRAM ECC Error Flag (DMERR)
60 * 0 Single-bit DRAM ECC Error Flag (DSERR)
61 */
62#define X38_ERRSTS_UE 0x0002
63#define X38_ERRSTS_CE 0x0001
64#define X38_ERRSTS_BITS (X38_ERRSTS_UE | X38_ERRSTS_CE)
65
66
67/* Intel MMIO register space - device 0 function 0 - MMR space */
68
69#define X38_C0DRB 0x200 /* Channel 0 DRAM Rank Boundary (16b x 4)
70 *
71 * 15:10 reserved
72 * 9:0 Channel 0 DRAM Rank Boundary Address
73 */
74#define X38_C1DRB 0x600 /* Channel 1 DRAM Rank Boundary (16b x 4) */
75#define X38_DRB_MASK 0x3ff /* bits 9:0 */
76#define X38_DRB_SHIFT 26 /* 64MiB grain */
77
78#define X38_C0ECCERRLOG 0x280 /* Channel 0 ECC Error Log (64b)
79 *
80 * 63:48 Error Column Address (ERRCOL)
81 * 47:32 Error Row Address (ERRROW)
82 * 31:29 Error Bank Address (ERRBANK)
83 * 28:27 Error Rank Address (ERRRANK)
84 * 26:24 reserved
85 * 23:16 Error Syndrome (ERRSYND)
86 * 15: 2 reserved
87 * 1 Multiple Bit Error Status (MERRSTS)
88 * 0 Correctable Error Status (CERRSTS)
89 */
90#define X38_C1ECCERRLOG 0x680 /* Channel 1 ECC Error Log (64b) */
91#define X38_ECCERRLOG_CE 0x1
92#define X38_ECCERRLOG_UE 0x2
93#define X38_ECCERRLOG_RANK_BITS 0x18000000
94#define X38_ECCERRLOG_SYNDROME_BITS 0xff0000
95
96#define X38_CAPID0 0xe0 /* see P.94 of spec for details */
97
98static int x38_channel_num;
99
100static int how_many_channel(struct pci_dev *pdev)
101{
102 unsigned char capid0_8b; /* 8th byte of CAPID0 */
103
104 pci_read_config_byte(dev: pdev, X38_CAPID0 + 8, val: &capid0_8b);
105 if (capid0_8b & 0x20) { /* check DCD: Dual Channel Disable */
106 edac_dbg(0, "In single channel mode\n");
107 x38_channel_num = 1;
108 } else {
109 edac_dbg(0, "In dual channel mode\n");
110 x38_channel_num = 2;
111 }
112
113 return x38_channel_num;
114}
115
116static unsigned long eccerrlog_syndrome(u64 log)
117{
118 return (log & X38_ECCERRLOG_SYNDROME_BITS) >> 16;
119}
120
121static int eccerrlog_row(int channel, u64 log)
122{
123 return ((log & X38_ECCERRLOG_RANK_BITS) >> 27) |
124 (channel * X38_RANKS_PER_CHANNEL);
125}
126
127enum x38_chips {
128 X38 = 0,
129};
130
131struct x38_dev_info {
132 const char *ctl_name;
133};
134
135struct x38_error_info {
136 u16 errsts;
137 u16 errsts2;
138 u64 eccerrlog[X38_CHANNELS];
139};
140
141static const struct x38_dev_info x38_devs[] = {
142 [X38] = {
143 .ctl_name = "x38"},
144};
145
146static struct pci_dev *mci_pdev;
147static int x38_registered = 1;
148
149
150static void x38_clear_error_info(struct mem_ctl_info *mci)
151{
152 struct pci_dev *pdev;
153
154 pdev = to_pci_dev(mci->pdev);
155
156 /*
157 * Clear any error bits.
158 * (Yes, we really clear bits by writing 1 to them.)
159 */
160 pci_write_bits16(pdev, X38_ERRSTS, X38_ERRSTS_BITS,
161 X38_ERRSTS_BITS);
162}
163
164static void x38_get_and_clear_error_info(struct mem_ctl_info *mci,
165 struct x38_error_info *info)
166{
167 struct pci_dev *pdev;
168 void __iomem *window = mci->pvt_info;
169
170 pdev = to_pci_dev(mci->pdev);
171
172 /*
173 * This is a mess because there is no atomic way to read all the
174 * registers at once and the registers can transition from CE being
175 * overwritten by UE.
176 */
177 pci_read_config_word(dev: pdev, X38_ERRSTS, val: &info->errsts);
178 if (!(info->errsts & X38_ERRSTS_BITS))
179 return;
180
181 info->eccerrlog[0] = lo_hi_readq(addr: window + X38_C0ECCERRLOG);
182 if (x38_channel_num == 2)
183 info->eccerrlog[1] = lo_hi_readq(addr: window + X38_C1ECCERRLOG);
184
185 pci_read_config_word(dev: pdev, X38_ERRSTS, val: &info->errsts2);
186
187 /*
188 * If the error is the same for both reads then the first set
189 * of reads is valid. If there is a change then there is a CE
190 * with no info and the second set of reads is valid and
191 * should be UE info.
192 */
193 if ((info->errsts ^ info->errsts2) & X38_ERRSTS_BITS) {
194 info->eccerrlog[0] = lo_hi_readq(addr: window + X38_C0ECCERRLOG);
195 if (x38_channel_num == 2)
196 info->eccerrlog[1] =
197 lo_hi_readq(addr: window + X38_C1ECCERRLOG);
198 }
199
200 x38_clear_error_info(mci);
201}
202
203static void x38_process_error_info(struct mem_ctl_info *mci,
204 struct x38_error_info *info)
205{
206 int channel;
207 u64 log;
208
209 if (!(info->errsts & X38_ERRSTS_BITS))
210 return;
211
212 if ((info->errsts ^ info->errsts2) & X38_ERRSTS_BITS) {
213 edac_mc_handle_error(type: HW_EVENT_ERR_UNCORRECTED, mci, error_count: 1, page_frame_number: 0, offset_in_page: 0, syndrome: 0,
214 top_layer: -1, mid_layer: -1, low_layer: -1,
215 msg: "UE overwrote CE", other_detail: "");
216 info->errsts = info->errsts2;
217 }
218
219 for (channel = 0; channel < x38_channel_num; channel++) {
220 log = info->eccerrlog[channel];
221 if (log & X38_ECCERRLOG_UE) {
222 edac_mc_handle_error(type: HW_EVENT_ERR_UNCORRECTED, mci, error_count: 1,
223 page_frame_number: 0, offset_in_page: 0, syndrome: 0,
224 top_layer: eccerrlog_row(channel, log),
225 mid_layer: -1, low_layer: -1,
226 msg: "x38 UE", other_detail: "");
227 } else if (log & X38_ECCERRLOG_CE) {
228 edac_mc_handle_error(type: HW_EVENT_ERR_CORRECTED, mci, error_count: 1,
229 page_frame_number: 0, offset_in_page: 0, syndrome: eccerrlog_syndrome(log),
230 top_layer: eccerrlog_row(channel, log),
231 mid_layer: -1, low_layer: -1,
232 msg: "x38 CE", other_detail: "");
233 }
234 }
235}
236
237static void x38_check(struct mem_ctl_info *mci)
238{
239 struct x38_error_info info;
240
241 x38_get_and_clear_error_info(mci, info: &info);
242 x38_process_error_info(mci, info: &info);
243}
244
245static void __iomem *x38_map_mchbar(struct pci_dev *pdev)
246{
247 union {
248 u64 mchbar;
249 struct {
250 u32 mchbar_low;
251 u32 mchbar_high;
252 };
253 } u;
254 void __iomem *window;
255
256 pci_read_config_dword(dev: pdev, X38_MCHBAR_LOW, val: &u.mchbar_low);
257 pci_write_config_dword(dev: pdev, X38_MCHBAR_LOW, val: u.mchbar_low | 0x1);
258 pci_read_config_dword(dev: pdev, X38_MCHBAR_HIGH, val: &u.mchbar_high);
259 u.mchbar &= X38_MCHBAR_MASK;
260
261 if (u.mchbar != (resource_size_t)u.mchbar) {
262 printk(KERN_ERR
263 "x38: mmio space beyond accessible range (0x%llx)\n",
264 (unsigned long long)u.mchbar);
265 return NULL;
266 }
267
268 window = ioremap(offset: u.mchbar, X38_MMR_WINDOW_SIZE);
269 if (!window)
270 printk(KERN_ERR "x38: cannot map mmio space at 0x%llx\n",
271 (unsigned long long)u.mchbar);
272
273 return window;
274}
275
276
277static void x38_get_drbs(void __iomem *window,
278 u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL])
279{
280 int i;
281
282 for (i = 0; i < X38_RANKS_PER_CHANNEL; i++) {
283 drbs[0][i] = readw(addr: window + X38_C0DRB + 2*i) & X38_DRB_MASK;
284 drbs[1][i] = readw(addr: window + X38_C1DRB + 2*i) & X38_DRB_MASK;
285 }
286}
287
288static bool x38_is_stacked(struct pci_dev *pdev,
289 u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL])
290{
291 u16 tom;
292
293 pci_read_config_word(dev: pdev, X38_TOM, val: &tom);
294 tom &= X38_TOM_MASK;
295
296 return drbs[X38_CHANNELS - 1][X38_RANKS_PER_CHANNEL - 1] == tom;
297}
298
299static unsigned long drb_to_nr_pages(
300 u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL],
301 bool stacked, int channel, int rank)
302{
303 int n;
304
305 n = drbs[channel][rank];
306 if (rank > 0)
307 n -= drbs[channel][rank - 1];
308 if (stacked && (channel == 1) && drbs[channel][rank] ==
309 drbs[channel][X38_RANKS_PER_CHANNEL - 1]) {
310 n -= drbs[0][X38_RANKS_PER_CHANNEL - 1];
311 }
312
313 n <<= (X38_DRB_SHIFT - PAGE_SHIFT);
314 return n;
315}
316
317static int x38_probe1(struct pci_dev *pdev, int dev_idx)
318{
319 int rc;
320 int i, j;
321 struct mem_ctl_info *mci = NULL;
322 struct edac_mc_layer layers[2];
323 u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL];
324 bool stacked;
325 void __iomem *window;
326
327 edac_dbg(0, "MC:\n");
328
329 window = x38_map_mchbar(pdev);
330 if (!window)
331 return -ENODEV;
332
333 x38_get_drbs(window, drbs);
334
335 how_many_channel(pdev);
336
337 /* FIXME: unconventional pvt_info usage */
338 layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
339 layers[0].size = X38_RANKS;
340 layers[0].is_virt_csrow = true;
341 layers[1].type = EDAC_MC_LAYER_CHANNEL;
342 layers[1].size = x38_channel_num;
343 layers[1].is_virt_csrow = false;
344 mci = edac_mc_alloc(mc_num: 0, ARRAY_SIZE(layers), layers, sz_pvt: 0);
345 if (!mci)
346 return -ENOMEM;
347
348 edac_dbg(3, "MC: init mci\n");
349
350 mci->pdev = &pdev->dev;
351 mci->mtype_cap = MEM_FLAG_DDR2;
352
353 mci->edac_ctl_cap = EDAC_FLAG_SECDED;
354 mci->edac_cap = EDAC_FLAG_SECDED;
355
356 mci->mod_name = EDAC_MOD_STR;
357 mci->ctl_name = x38_devs[dev_idx].ctl_name;
358 mci->dev_name = pci_name(pdev);
359 mci->edac_check = x38_check;
360 mci->ctl_page_to_phys = NULL;
361 mci->pvt_info = window;
362
363 stacked = x38_is_stacked(pdev, drbs);
364
365 /*
366 * The dram rank boundary (DRB) reg values are boundary addresses
367 * for each DRAM rank with a granularity of 64MB. DRB regs are
368 * cumulative; the last one will contain the total memory
369 * contained in all ranks.
370 */
371 for (i = 0; i < mci->nr_csrows; i++) {
372 unsigned long nr_pages;
373 struct csrow_info *csrow = mci->csrows[i];
374
375 nr_pages = drb_to_nr_pages(drbs, stacked,
376 channel: i / X38_RANKS_PER_CHANNEL,
377 rank: i % X38_RANKS_PER_CHANNEL);
378
379 if (nr_pages == 0)
380 continue;
381
382 for (j = 0; j < x38_channel_num; j++) {
383 struct dimm_info *dimm = csrow->channels[j]->dimm;
384
385 dimm->nr_pages = nr_pages / x38_channel_num;
386 dimm->grain = nr_pages << PAGE_SHIFT;
387 dimm->mtype = MEM_DDR2;
388 dimm->dtype = DEV_UNKNOWN;
389 dimm->edac_mode = EDAC_UNKNOWN;
390 }
391 }
392
393 x38_clear_error_info(mci);
394
395 rc = -ENODEV;
396 if (edac_mc_add_mc(mci)) {
397 edac_dbg(3, "MC: failed edac_mc_add_mc()\n");
398 goto fail;
399 }
400
401 /* get this far and it's successful */
402 edac_dbg(3, "MC: success\n");
403 return 0;
404
405fail:
406 iounmap(addr: window);
407 if (mci)
408 edac_mc_free(mci);
409
410 return rc;
411}
412
413static int x38_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
414{
415 int rc;
416
417 edac_dbg(0, "MC:\n");
418
419 if (pci_enable_device(dev: pdev) < 0)
420 return -EIO;
421
422 rc = x38_probe1(pdev, dev_idx: ent->driver_data);
423 if (!mci_pdev)
424 mci_pdev = pci_dev_get(dev: pdev);
425
426 return rc;
427}
428
429static void x38_remove_one(struct pci_dev *pdev)
430{
431 struct mem_ctl_info *mci;
432
433 edac_dbg(0, "\n");
434
435 mci = edac_mc_del_mc(dev: &pdev->dev);
436 if (!mci)
437 return;
438
439 iounmap(addr: mci->pvt_info);
440
441 edac_mc_free(mci);
442}
443
444static const struct pci_device_id x38_pci_tbl[] = {
445 {
446 PCI_VEND_DEV(INTEL, X38_HB), PCI_ANY_ID, PCI_ANY_ID, 0, 0,
447 X38},
448 {
449 0,
450 } /* 0 terminated list. */
451};
452
453MODULE_DEVICE_TABLE(pci, x38_pci_tbl);
454
455static struct pci_driver x38_driver = {
456 .name = EDAC_MOD_STR,
457 .probe = x38_init_one,
458 .remove = x38_remove_one,
459 .id_table = x38_pci_tbl,
460};
461
462static int __init x38_init(void)
463{
464 int pci_rc;
465
466 edac_dbg(3, "MC:\n");
467
468 /* Ensure that the OPSTATE is set correctly for POLL or NMI */
469 opstate_init();
470
471 pci_rc = pci_register_driver(&x38_driver);
472 if (pci_rc < 0)
473 goto fail0;
474
475 if (!mci_pdev) {
476 x38_registered = 0;
477 mci_pdev = pci_get_device(PCI_VENDOR_ID_INTEL,
478 PCI_DEVICE_ID_INTEL_X38_HB, NULL);
479 if (!mci_pdev) {
480 edac_dbg(0, "x38 pci_get_device fail\n");
481 pci_rc = -ENODEV;
482 goto fail1;
483 }
484
485 pci_rc = x38_init_one(pdev: mci_pdev, ent: x38_pci_tbl);
486 if (pci_rc < 0) {
487 edac_dbg(0, "x38 init fail\n");
488 pci_rc = -ENODEV;
489 goto fail1;
490 }
491 }
492
493 return 0;
494
495fail1:
496 pci_unregister_driver(dev: &x38_driver);
497
498fail0:
499 pci_dev_put(dev: mci_pdev);
500
501 return pci_rc;
502}
503
504static void __exit x38_exit(void)
505{
506 edac_dbg(3, "MC:\n");
507
508 pci_unregister_driver(dev: &x38_driver);
509 if (!x38_registered) {
510 x38_remove_one(pdev: mci_pdev);
511 pci_dev_put(dev: mci_pdev);
512 }
513}
514
515module_init(x38_init);
516module_exit(x38_exit);
517
518MODULE_LICENSE("GPL");
519MODULE_AUTHOR("Cluster Computing, Inc. Hitoshi Mitake");
520MODULE_DESCRIPTION("MC support for Intel X38 memory hub controllers");
521
522module_param(edac_op_state, int, 0444);
523MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");
524

source code of linux/drivers/edac/x38_edac.c