driver-core: fix devtmpfs crash on s390
[linux-2.6/linux-2.6-openrd.git] / drivers / edac / i82443bxgx_edac.c
blob577760a82a0f7d5519cd2631ccf1d7fd99f3ec05
1 /*
2 * Intel 82443BX/GX (440BX/GX chipset) Memory Controller EDAC kernel
3 * module (C) 2006 Tim Small
5 * This file may be distributed under the terms of the GNU General
6 * Public License.
8 * Written by Tim Small <tim@buttersideup.com>, based on work by Linux
9 * Networx, Thayne Harbaugh, Dan Hollis <goemon at anime dot net> and
10 * others.
12 * 440GX fix by Jason Uhlenkott <juhlenko@akamai.com>.
14 * Written with reference to 82443BX Host Bridge Datasheet:
15 * http://www.intel.com/design/chipsets/440/documentation.htm
16 * references to this document given in [].
18 * This module doesn't support the 440LX, but it may be possible to
19 * make it do so (the 440LX's register definitions are different, but
20 * not completely so - I haven't studied them in enough detail to know
21 * how easy this would be).
24 #include <linux/module.h>
25 #include <linux/init.h>
27 #include <linux/pci.h>
28 #include <linux/pci_ids.h>
30 #include <linux/slab.h>
32 #include <linux/edac.h>
33 #include "edac_core.h"
35 #define I82443_REVISION "0.1"
37 #define EDAC_MOD_STR "i82443bxgx_edac"
39 /* The 82443BX supports SDRAM, or EDO (EDO for mobile only), "Memory
40 * Size: 8 MB to 512 MB (1GB with Registered DIMMs) with eight memory
41 * rows" "The 82443BX supports multiple-bit error detection and
42 * single-bit error correction when ECC mode is enabled and
43 * single/multi-bit error detection when correction is disabled.
44 * During writes to the DRAM, the 82443BX generates ECC for the data
45 * on a QWord basis. Partial QWord writes require a read-modify-write
46 * cycle when ECC is enabled."
49 /* "Additionally, the 82443BX ensures that the data is corrected in
50 * main memory so that accumulation of errors is prevented. Another
51 * error within the same QWord would result in a double-bit error
52 * which is unrecoverable. This is known as hardware scrubbing since
53 * it requires no software intervention to correct the data in memory."
56 /* [Also see page 100 (section 4.3), "DRAM Interface"]
57 * [Also see page 112 (section 4.6.1.4), ECC]
60 #define I82443BXGX_NR_CSROWS 8
61 #define I82443BXGX_NR_CHANS 1
62 #define I82443BXGX_NR_DIMMS 4
64 /* 82443 PCI Device 0 */
65 #define I82443BXGX_NBXCFG 0x50 /* 32bit register starting at this PCI
66 * config space offset */
67 #define I82443BXGX_NBXCFG_OFFSET_NON_ECCROW 24 /* Array of bits, zero if
68 * row is non-ECC */
69 #define I82443BXGX_NBXCFG_OFFSET_DRAM_FREQ 12 /* 2 bits,00=100MHz,10=66 MHz */
71 #define I82443BXGX_NBXCFG_OFFSET_DRAM_INTEGRITY 7 /* 2 bits: */
72 #define I82443BXGX_NBXCFG_INTEGRITY_NONE 0x0 /* 00 = Non-ECC */
73 #define I82443BXGX_NBXCFG_INTEGRITY_EC 0x1 /* 01 = EC (only) */
74 #define I82443BXGX_NBXCFG_INTEGRITY_ECC 0x2 /* 10 = ECC */
75 #define I82443BXGX_NBXCFG_INTEGRITY_SCRUB 0x3 /* 11 = ECC + HW Scrub */
77 #define I82443BXGX_NBXCFG_OFFSET_ECC_DIAG_ENABLE 6
79 /* 82443 PCI Device 0 */
80 #define I82443BXGX_EAP 0x80 /* 32bit register starting at this PCI
81 * config space offset, Error Address
82 * Pointer Register */
83 #define I82443BXGX_EAP_OFFSET_EAP 12 /* High 20 bits of error address */
84 #define I82443BXGX_EAP_OFFSET_MBE BIT(1) /* Err at EAP was multi-bit (W1TC) */
85 #define I82443BXGX_EAP_OFFSET_SBE BIT(0) /* Err at EAP was single-bit (W1TC) */
87 #define I82443BXGX_ERRCMD 0x90 /* 8bit register starting at this PCI
88 * config space offset. */
89 #define I82443BXGX_ERRCMD_OFFSET_SERR_ON_MBE BIT(1) /* 1 = enable */
90 #define I82443BXGX_ERRCMD_OFFSET_SERR_ON_SBE BIT(0) /* 1 = enable */
92 #define I82443BXGX_ERRSTS 0x91 /* 16bit register starting at this PCI
93 * config space offset. */
94 #define I82443BXGX_ERRSTS_OFFSET_MBFRE 5 /* 3 bits - first err row multibit */
95 #define I82443BXGX_ERRSTS_OFFSET_MEF BIT(4) /* 1 = MBE occurred */
96 #define I82443BXGX_ERRSTS_OFFSET_SBFRE 1 /* 3 bits - first err row singlebit */
97 #define I82443BXGX_ERRSTS_OFFSET_SEF BIT(0) /* 1 = SBE occurred */
99 #define I82443BXGX_DRAMC 0x57 /* 8bit register starting at this PCI
100 * config space offset. */
101 #define I82443BXGX_DRAMC_OFFSET_DT 3 /* 2 bits, DRAM Type */
102 #define I82443BXGX_DRAMC_DRAM_IS_EDO 0 /* 00 = EDO */
103 #define I82443BXGX_DRAMC_DRAM_IS_SDRAM 1 /* 01 = SDRAM */
104 #define I82443BXGX_DRAMC_DRAM_IS_RSDRAM 2 /* 10 = Registered SDRAM */
106 #define I82443BXGX_DRB 0x60 /* 8x 8bit registers starting at this PCI
107 * config space offset. */
109 /* FIXME - don't poll when ECC disabled? */
111 struct i82443bxgx_edacmc_error_info {
112 u32 eap;
115 static struct edac_pci_ctl_info *i82443bxgx_pci;
117 static struct pci_dev *mci_pdev; /* init dev: in case that AGP code has
118 * already registered driver
121 static int i82443bxgx_registered = 1;
123 static void i82443bxgx_edacmc_get_error_info(struct mem_ctl_info *mci,
124 struct i82443bxgx_edacmc_error_info
125 *info)
127 struct pci_dev *pdev;
128 pdev = to_pci_dev(mci->dev);
129 pci_read_config_dword(pdev, I82443BXGX_EAP, &info->eap);
130 if (info->eap & I82443BXGX_EAP_OFFSET_SBE)
131 /* Clear error to allow next error to be reported [p.61] */
132 pci_write_bits32(pdev, I82443BXGX_EAP,
133 I82443BXGX_EAP_OFFSET_SBE,
134 I82443BXGX_EAP_OFFSET_SBE);
136 if (info->eap & I82443BXGX_EAP_OFFSET_MBE)
137 /* Clear error to allow next error to be reported [p.61] */
138 pci_write_bits32(pdev, I82443BXGX_EAP,
139 I82443BXGX_EAP_OFFSET_MBE,
140 I82443BXGX_EAP_OFFSET_MBE);
143 static int i82443bxgx_edacmc_process_error_info(struct mem_ctl_info *mci,
144 struct
145 i82443bxgx_edacmc_error_info
146 *info, int handle_errors)
148 int error_found = 0;
149 u32 eapaddr, page, pageoffset;
151 /* bits 30:12 hold the 4kb block in which the error occurred
152 * [p.61] */
153 eapaddr = (info->eap & 0xfffff000);
154 page = eapaddr >> PAGE_SHIFT;
155 pageoffset = eapaddr - (page << PAGE_SHIFT);
157 if (info->eap & I82443BXGX_EAP_OFFSET_SBE) {
158 error_found = 1;
159 if (handle_errors)
160 edac_mc_handle_ce(mci, page, pageoffset,
161 /* 440BX/GX don't make syndrome information
162 * available */
163 0, edac_mc_find_csrow_by_page(mci, page), 0,
164 mci->ctl_name);
167 if (info->eap & I82443BXGX_EAP_OFFSET_MBE) {
168 error_found = 1;
169 if (handle_errors)
170 edac_mc_handle_ue(mci, page, pageoffset,
171 edac_mc_find_csrow_by_page(mci, page),
172 mci->ctl_name);
175 return error_found;
178 static void i82443bxgx_edacmc_check(struct mem_ctl_info *mci)
180 struct i82443bxgx_edacmc_error_info info;
182 debugf1("MC%d: " __FILE__ ": %s()\n", mci->mc_idx, __func__);
183 i82443bxgx_edacmc_get_error_info(mci, &info);
184 i82443bxgx_edacmc_process_error_info(mci, &info, 1);
187 static void i82443bxgx_init_csrows(struct mem_ctl_info *mci,
188 struct pci_dev *pdev,
189 enum edac_type edac_mode,
190 enum mem_type mtype)
192 struct csrow_info *csrow;
193 int index;
194 u8 drbar, dramc;
195 u32 row_base, row_high_limit, row_high_limit_last;
197 pci_read_config_byte(pdev, I82443BXGX_DRAMC, &dramc);
198 row_high_limit_last = 0;
199 for (index = 0; index < mci->nr_csrows; index++) {
200 csrow = &mci->csrows[index];
201 pci_read_config_byte(pdev, I82443BXGX_DRB + index, &drbar);
202 debugf1("MC%d: " __FILE__ ": %s() Row=%d DRB = %#0x\n",
203 mci->mc_idx, __func__, index, drbar);
204 row_high_limit = ((u32) drbar << 23);
205 /* find the DRAM Chip Select Base address and mask */
206 debugf1("MC%d: " __FILE__ ": %s() Row=%d, "
207 "Boundry Address=%#0x, Last = %#0x \n",
208 mci->mc_idx, __func__, index, row_high_limit,
209 row_high_limit_last);
211 /* 440GX goes to 2GB, represented with a DRB of 0. */
212 if (row_high_limit_last && !row_high_limit)
213 row_high_limit = 1UL << 31;
215 /* This row is empty [p.49] */
216 if (row_high_limit == row_high_limit_last)
217 continue;
218 row_base = row_high_limit_last;
219 csrow->first_page = row_base >> PAGE_SHIFT;
220 csrow->last_page = (row_high_limit >> PAGE_SHIFT) - 1;
221 csrow->nr_pages = csrow->last_page - csrow->first_page + 1;
222 /* EAP reports in 4kilobyte granularity [61] */
223 csrow->grain = 1 << 12;
224 csrow->mtype = mtype;
225 /* I don't think 440BX can tell you device type? FIXME? */
226 csrow->dtype = DEV_UNKNOWN;
227 /* Mode is global to all rows on 440BX */
228 csrow->edac_mode = edac_mode;
229 row_high_limit_last = row_high_limit;
233 static int i82443bxgx_edacmc_probe1(struct pci_dev *pdev, int dev_idx)
235 struct mem_ctl_info *mci;
236 u8 dramc;
237 u32 nbxcfg, ecc_mode;
238 enum mem_type mtype;
239 enum edac_type edac_mode;
241 debugf0("MC: " __FILE__ ": %s()\n", __func__);
243 /* Something is really hosed if PCI config space reads from
244 * the MC aren't working.
246 if (pci_read_config_dword(pdev, I82443BXGX_NBXCFG, &nbxcfg))
247 return -EIO;
249 mci = edac_mc_alloc(0, I82443BXGX_NR_CSROWS, I82443BXGX_NR_CHANS, 0);
251 if (mci == NULL)
252 return -ENOMEM;
254 debugf0("MC: " __FILE__ ": %s(): mci = %p\n", __func__, mci);
255 mci->dev = &pdev->dev;
256 mci->mtype_cap = MEM_FLAG_EDO | MEM_FLAG_SDR | MEM_FLAG_RDR;
257 mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
258 pci_read_config_byte(pdev, I82443BXGX_DRAMC, &dramc);
259 switch ((dramc >> I82443BXGX_DRAMC_OFFSET_DT) & (BIT(0) | BIT(1))) {
260 case I82443BXGX_DRAMC_DRAM_IS_EDO:
261 mtype = MEM_EDO;
262 break;
263 case I82443BXGX_DRAMC_DRAM_IS_SDRAM:
264 mtype = MEM_SDR;
265 break;
266 case I82443BXGX_DRAMC_DRAM_IS_RSDRAM:
267 mtype = MEM_RDR;
268 break;
269 default:
270 debugf0("Unknown/reserved DRAM type value "
271 "in DRAMC register!\n");
272 mtype = -MEM_UNKNOWN;
275 if ((mtype == MEM_SDR) || (mtype == MEM_RDR))
276 mci->edac_cap = mci->edac_ctl_cap;
277 else
278 mci->edac_cap = EDAC_FLAG_NONE;
280 mci->scrub_cap = SCRUB_FLAG_HW_SRC;
281 pci_read_config_dword(pdev, I82443BXGX_NBXCFG, &nbxcfg);
282 ecc_mode = ((nbxcfg >> I82443BXGX_NBXCFG_OFFSET_DRAM_INTEGRITY) &
283 (BIT(0) | BIT(1)));
285 mci->scrub_mode = (ecc_mode == I82443BXGX_NBXCFG_INTEGRITY_SCRUB)
286 ? SCRUB_HW_SRC : SCRUB_NONE;
288 switch (ecc_mode) {
289 case I82443BXGX_NBXCFG_INTEGRITY_NONE:
290 edac_mode = EDAC_NONE;
291 break;
292 case I82443BXGX_NBXCFG_INTEGRITY_EC:
293 edac_mode = EDAC_EC;
294 break;
295 case I82443BXGX_NBXCFG_INTEGRITY_ECC:
296 case I82443BXGX_NBXCFG_INTEGRITY_SCRUB:
297 edac_mode = EDAC_SECDED;
298 break;
299 default:
300 debugf0("%s(): Unknown/reserved ECC state "
301 "in NBXCFG register!\n", __func__);
302 edac_mode = EDAC_UNKNOWN;
303 break;
306 i82443bxgx_init_csrows(mci, pdev, edac_mode, mtype);
308 /* Many BIOSes don't clear error flags on boot, so do this
309 * here, or we get "phantom" errors occuring at module-load
310 * time. */
311 pci_write_bits32(pdev, I82443BXGX_EAP,
312 (I82443BXGX_EAP_OFFSET_SBE |
313 I82443BXGX_EAP_OFFSET_MBE),
314 (I82443BXGX_EAP_OFFSET_SBE |
315 I82443BXGX_EAP_OFFSET_MBE));
317 mci->mod_name = EDAC_MOD_STR;
318 mci->mod_ver = I82443_REVISION;
319 mci->ctl_name = "I82443BXGX";
320 mci->dev_name = pci_name(pdev);
321 mci->edac_check = i82443bxgx_edacmc_check;
322 mci->ctl_page_to_phys = NULL;
324 if (edac_mc_add_mc(mci)) {
325 debugf3("%s(): failed edac_mc_add_mc()\n", __func__);
326 goto fail;
329 /* allocating generic PCI control info */
330 i82443bxgx_pci = edac_pci_create_generic_ctl(&pdev->dev, EDAC_MOD_STR);
331 if (!i82443bxgx_pci) {
332 printk(KERN_WARNING
333 "%s(): Unable to create PCI control\n",
334 __func__);
335 printk(KERN_WARNING
336 "%s(): PCI error report via EDAC not setup\n",
337 __func__);
340 debugf3("MC: " __FILE__ ": %s(): success\n", __func__);
341 return 0;
343 fail:
344 edac_mc_free(mci);
345 return -ENODEV;
348 EXPORT_SYMBOL_GPL(i82443bxgx_edacmc_probe1);
350 /* returns count (>= 0), or negative on error */
351 static int __devinit i82443bxgx_edacmc_init_one(struct pci_dev *pdev,
352 const struct pci_device_id *ent)
354 int rc;
356 debugf0("MC: " __FILE__ ": %s()\n", __func__);
358 /* don't need to call pci_device_enable() */
359 rc = i82443bxgx_edacmc_probe1(pdev, ent->driver_data);
361 if (mci_pdev == NULL)
362 mci_pdev = pci_dev_get(pdev);
364 return rc;
367 static void __devexit i82443bxgx_edacmc_remove_one(struct pci_dev *pdev)
369 struct mem_ctl_info *mci;
371 debugf0(__FILE__ ": %s()\n", __func__);
373 if (i82443bxgx_pci)
374 edac_pci_release_generic_ctl(i82443bxgx_pci);
376 if ((mci = edac_mc_del_mc(&pdev->dev)) == NULL)
377 return;
379 edac_mc_free(mci);
382 EXPORT_SYMBOL_GPL(i82443bxgx_edacmc_remove_one);
384 static const struct pci_device_id i82443bxgx_pci_tbl[] __devinitdata = {
385 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443BX_0)},
386 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443BX_2)},
387 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443GX_0)},
388 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443GX_2)},
389 {0,} /* 0 terminated list. */
392 MODULE_DEVICE_TABLE(pci, i82443bxgx_pci_tbl);
394 static struct pci_driver i82443bxgx_edacmc_driver = {
395 .name = EDAC_MOD_STR,
396 .probe = i82443bxgx_edacmc_init_one,
397 .remove = __devexit_p(i82443bxgx_edacmc_remove_one),
398 .id_table = i82443bxgx_pci_tbl,
401 static int __init i82443bxgx_edacmc_init(void)
403 int pci_rc;
404 /* Ensure that the OPSTATE is set correctly for POLL or NMI */
405 opstate_init();
407 pci_rc = pci_register_driver(&i82443bxgx_edacmc_driver);
408 if (pci_rc < 0)
409 goto fail0;
411 if (mci_pdev == NULL) {
412 const struct pci_device_id *id = &i82443bxgx_pci_tbl[0];
413 int i = 0;
414 i82443bxgx_registered = 0;
416 while (mci_pdev == NULL && id->vendor != 0) {
417 mci_pdev = pci_get_device(id->vendor,
418 id->device, NULL);
419 i++;
420 id = &i82443bxgx_pci_tbl[i];
422 if (!mci_pdev) {
423 debugf0("i82443bxgx pci_get_device fail\n");
424 pci_rc = -ENODEV;
425 goto fail1;
428 pci_rc = i82443bxgx_edacmc_init_one(mci_pdev, i82443bxgx_pci_tbl);
430 if (pci_rc < 0) {
431 debugf0("i82443bxgx init fail\n");
432 pci_rc = -ENODEV;
433 goto fail1;
437 return 0;
439 fail1:
440 pci_unregister_driver(&i82443bxgx_edacmc_driver);
442 fail0:
443 if (mci_pdev != NULL)
444 pci_dev_put(mci_pdev);
446 return pci_rc;
449 static void __exit i82443bxgx_edacmc_exit(void)
451 pci_unregister_driver(&i82443bxgx_edacmc_driver);
453 if (!i82443bxgx_registered)
454 i82443bxgx_edacmc_remove_one(mci_pdev);
456 if (mci_pdev)
457 pci_dev_put(mci_pdev);
460 module_init(i82443bxgx_edacmc_init);
461 module_exit(i82443bxgx_edacmc_exit);
463 MODULE_LICENSE("GPL");
464 MODULE_AUTHOR("Tim Small <tim@buttersideup.com> - WPAD");
465 MODULE_DESCRIPTION("EDAC MC support for Intel 82443BX/GX memory controllers");
467 module_param(edac_op_state, int, 0444);
468 MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");