xref: /linux/drivers/edac/r82600_edac.c (revision 666ed8bfd1de3b091cf32ca03b651757dd86cfff)
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_module.h"
24 
25 #define EDAC_MOD_STR	"r82600_edac"
26 
27 #define r82600_printk(level, fmt, arg...) \
28 	edac_printk(level, "r82600", fmt, ##arg)
29 
30 #define r82600_mc_printk(mci, level, fmt, arg...) \
31 	edac_mc_chipset_printk(mci, level, "r82600", fmt, ##arg)
32 
33 /* Radisys say "The 82600 integrates a main memory SDRAM controller that
34  * supports up to four banks of memory. The four banks can support a mix of
35  * sizes of 64 bit wide (72 bits with ECC) Synchronous DRAM (SDRAM) DIMMs,
36  * each of which can be any size from 16MB to 512MB. Both registered (control
37  * signals buffered) and unbuffered DIMM types are supported. Mixing of
38  * registered and unbuffered DIMMs as well as mixing of ECC and non-ECC DIMMs
39  * is not allowed. The 82600 SDRAM interface operates at the same frequency as
40  * the CPU bus, 66MHz, 100MHz or 133MHz."
41  */
42 
43 #define R82600_NR_CSROWS 4
44 #define R82600_NR_CHANS  1
45 #define R82600_NR_DIMMS  4
46 
47 #define R82600_BRIDGE_ID  0x8200
48 
49 /* Radisys 82600 register addresses - device 0 function 0 - PCI bridge */
50 #define R82600_DRAMC	0x57	/* Various SDRAM related control bits
51 				 * all bits are R/W
52 				 *
53 				 * 7    SDRAM ISA Hole Enable
54 				 * 6    Flash Page Mode Enable
55 				 * 5    ECC Enable: 1=ECC 0=noECC
56 				 * 4    DRAM DIMM Type: 1=
57 				 * 3    BIOS Alias Disable
58 				 * 2    SDRAM BIOS Flash Write Enable
59 				 * 1:0  SDRAM Refresh Rate: 00=Disabled
60 				 *          01=7.8usec (256Mbit SDRAMs)
61 				 *          10=15.6us 11=125usec
62 				 */
63 
64 #define R82600_SDRAMC	0x76	/* "SDRAM Control Register"
65 				 * More SDRAM related control bits
66 				 * all bits are R/W
67 				 *
68 				 * 15:8 Reserved.
69 				 *
70 				 * 7:5  Special SDRAM Mode Select
71 				 *
72 				 * 4    Force ECC
73 				 *
74 				 *        1=Drive ECC bits to 0 during
75 				 *          write cycles (i.e. ECC test mode)
76 				 *
77 				 *        0=Normal ECC functioning
78 				 *
79 				 * 3    Enhanced Paging Enable
80 				 *
81 				 * 2    CAS# Latency 0=3clks 1=2clks
82 				 *
83 				 * 1    RAS# to CAS# Delay 0=3 1=2
84 				 *
85 				 * 0    RAS# Precharge     0=3 1=2
86 				 */
87 
88 #define R82600_EAP	0x80	/* ECC Error Address Pointer Register
89 				 *
90 				 * 31    Disable Hardware Scrubbing (RW)
91 				 *        0=Scrub on corrected read
92 				 *        1=Don't scrub on corrected read
93 				 *
94 				 * 30:12 Error Address Pointer (RO)
95 				 *        Upper 19 bits of error address
96 				 *
97 				 * 11:4  Syndrome Bits (RO)
98 				 *
99 				 * 3     BSERR# on multibit error (RW)
100 				 *        1=enable 0=disable
101 				 *
102 				 * 2     NMI on Single Bit Eror (RW)
103 				 *        1=NMI triggered by SBE n.b. other
104 				 *          prerequeists
105 				 *        0=NMI not triggered
106 				 *
107 				 * 1     MBE (R/WC)
108 				 *        read 1=MBE at EAP (see above)
109 				 *        read 0=no MBE, or SBE occurred first
110 				 *        write 1=Clear MBE status (must also
111 				 *          clear SBE)
112 				 *        write 0=NOP
113 				 *
114 				 * 1     SBE (R/WC)
115 				 *        read 1=SBE at EAP (see above)
116 				 *        read 0=no SBE, or MBE occurred first
117 				 *        write 1=Clear SBE status (must also
118 				 *          clear MBE)
119 				 *        write 0=NOP
120 				 */
121 
122 #define R82600_DRBA	0x60	/* + 0x60..0x63 SDRAM Row Boundary Address
123 				 *  Registers
124 				 *
125 				 * 7:0  Address lines 30:24 - upper limit of
126 				 * each row [p57]
127 				 */
128 
129 struct r82600_error_info {
130 	u32 eapr;
131 };
132 
133 static bool disable_hardware_scrub;
134 
135 static struct edac_pci_ctl_info *r82600_pci;
136 
137 static void r82600_get_error_info(struct mem_ctl_info *mci,
138 				struct r82600_error_info *info)
139 {
140 	struct pci_dev *pdev;
141 
142 	pdev = to_pci_dev(mci->pdev);
143 	pci_read_config_dword(pdev, R82600_EAP, &info->eapr);
144 
145 	if (info->eapr & BIT(0))
146 		/* Clear error to allow next error to be reported [p.62] */
147 		pci_write_bits32(pdev, R82600_EAP,
148 				 ((u32) BIT(0) & (u32) BIT(1)),
149 				 ((u32) BIT(0) & (u32) BIT(1)));
150 
151 	if (info->eapr & BIT(1))
152 		/* Clear error to allow next error to be reported [p.62] */
153 		pci_write_bits32(pdev, R82600_EAP,
154 				 ((u32) BIT(0) & (u32) BIT(1)),
155 				 ((u32) BIT(0) & (u32) BIT(1)));
156 }
157 
158 static int r82600_process_error_info(struct mem_ctl_info *mci,
159 				struct r82600_error_info *info,
160 				int handle_errors)
161 {
162 	int error_found;
163 	u32 eapaddr, page;
164 	u32 syndrome;
165 
166 	error_found = 0;
167 
168 	/* bits 30:12 store the upper 19 bits of the 32 bit error address */
169 	eapaddr = ((info->eapr >> 12) & 0x7FFF) << 13;
170 	/* Syndrome in bits 11:4 [p.62]       */
171 	syndrome = (info->eapr >> 4) & 0xFF;
172 
173 	/* the R82600 reports at less than page *
174 	 * granularity (upper 19 bits only)     */
175 	page = eapaddr >> PAGE_SHIFT;
176 
177 	if (info->eapr & BIT(0)) {	/* CE? */
178 		error_found = 1;
179 
180 		if (handle_errors)
181 			edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, 1,
182 					     page, 0, syndrome,
183 					     edac_mc_find_csrow_by_page(mci, page),
184 					     0, -1,
185 					     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_error(HW_EVENT_ERR_UNCORRECTED, mci, 1,
194 					     page, 0, 0,
195 					     edac_mc_find_csrow_by_page(mci, page),
196 					     0, -1,
197 					     mci->ctl_name, "");
198 	}
199 
200 	return error_found;
201 }
202 
203 static void r82600_check(struct mem_ctl_info *mci)
204 {
205 	struct r82600_error_info info;
206 
207 	edac_dbg(1, "MC%d\n", mci->mc_idx);
208 	r82600_get_error_info(mci, &info);
209 	r82600_process_error_info(mci, &info, 1);
210 }
211 
212 static inline int ecc_enabled(u8 dramcr)
213 {
214 	return dramcr & BIT(5);
215 }
216 
217 static void r82600_init_csrows(struct mem_ctl_info *mci, struct pci_dev *pdev,
218 			u8 dramcr)
219 {
220 	struct csrow_info *csrow;
221 	struct dimm_info *dimm;
222 	int index;
223 	u8 drbar;		/* SDRAM Row Boundary Address Register */
224 	u32 row_high_limit, row_high_limit_last;
225 	u32 reg_sdram, ecc_on, row_base;
226 
227 	ecc_on = ecc_enabled(dramcr);
228 	reg_sdram = dramcr & BIT(4);
229 	row_high_limit_last = 0;
230 
231 	for (index = 0; index < mci->nr_csrows; index++) {
232 		csrow = mci->csrows[index];
233 		dimm = csrow->channels[0]->dimm;
234 
235 		/* find the DRAM Chip Select Base address and mask */
236 		pci_read_config_byte(pdev, R82600_DRBA + index, &drbar);
237 
238 		edac_dbg(1, "Row=%d DRBA = %#0x\n", index, drbar);
239 
240 		row_high_limit = ((u32) drbar << 24);
241 /*		row_high_limit = ((u32)drbar << 24) | 0xffffffUL; */
242 
243 		edac_dbg(1, "Row=%d, Boundary Address=%#0x, Last = %#0x\n",
244 			 index, row_high_limit, row_high_limit_last);
245 
246 		/* Empty row [p.57] */
247 		if (row_high_limit == row_high_limit_last)
248 			continue;
249 
250 		row_base = row_high_limit_last;
251 
252 		csrow->first_page = row_base >> PAGE_SHIFT;
253 		csrow->last_page = (row_high_limit >> PAGE_SHIFT) - 1;
254 
255 		dimm->nr_pages = csrow->last_page - csrow->first_page + 1;
256 		/* Error address is top 19 bits - so granularity is      *
257 		 * 14 bits                                               */
258 		dimm->grain = 1 << 14;
259 		dimm->mtype = reg_sdram ? MEM_RDDR : MEM_DDR;
260 		/* FIXME - check that this is unknowable with this chipset */
261 		dimm->dtype = DEV_UNKNOWN;
262 
263 		/* Mode is global on 82600 */
264 		dimm->edac_mode = ecc_on ? EDAC_SECDED : EDAC_NONE;
265 		row_high_limit_last = row_high_limit;
266 	}
267 }
268 
269 static int r82600_probe1(struct pci_dev *pdev, int dev_idx)
270 {
271 	struct mem_ctl_info *mci;
272 	struct edac_mc_layer layers[2];
273 	u8 dramcr;
274 	u32 eapr;
275 	u32 scrub_disabled;
276 	u32 sdram_refresh_rate;
277 	struct r82600_error_info discard;
278 
279 	edac_dbg(0, "\n");
280 	pci_read_config_byte(pdev, R82600_DRAMC, &dramcr);
281 	pci_read_config_dword(pdev, R82600_EAP, &eapr);
282 	scrub_disabled = eapr & BIT(31);
283 	sdram_refresh_rate = dramcr & (BIT(0) | BIT(1));
284 	edac_dbg(2, "sdram refresh rate = %#0x\n", sdram_refresh_rate);
285 	edac_dbg(2, "DRAMC register = %#0x\n", dramcr);
286 	layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
287 	layers[0].size = R82600_NR_CSROWS;
288 	layers[0].is_virt_csrow = true;
289 	layers[1].type = EDAC_MC_LAYER_CHANNEL;
290 	layers[1].size = R82600_NR_CHANS;
291 	layers[1].is_virt_csrow = false;
292 	mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers, 0);
293 	if (mci == NULL)
294 		return -ENOMEM;
295 
296 	edac_dbg(0, "mci = %p\n", mci);
297 	mci->pdev = &pdev->dev;
298 	mci->mtype_cap = MEM_FLAG_RDDR | MEM_FLAG_DDR;
299 	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
300 	/* FIXME try to work out if the chip leads have been used for COM2
301 	 * instead on this board? [MA6?] MAYBE:
302 	 */
303 
304 	/* On the R82600, the pins for memory bits 72:65 - i.e. the   *
305 	 * EC bits are shared with the pins for COM2 (!), so if COM2  *
306 	 * is enabled, we assume COM2 is wired up, and thus no EDAC   *
307 	 * is possible.                                               */
308 	mci->edac_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
309 
310 	if (ecc_enabled(dramcr)) {
311 		if (scrub_disabled)
312 			edac_dbg(3, "mci = %p - Scrubbing disabled! EAP: %#0x\n",
313 				 mci, eapr);
314 	} else
315 		mci->edac_cap = EDAC_FLAG_NONE;
316 
317 	mci->mod_name = EDAC_MOD_STR;
318 	mci->ctl_name = "R82600";
319 	mci->dev_name = pci_name(pdev);
320 	mci->edac_check = r82600_check;
321 	mci->ctl_page_to_phys = NULL;
322 	r82600_init_csrows(mci, pdev, dramcr);
323 	r82600_get_error_info(mci, &discard);	/* clear counters */
324 
325 	/* Here we assume that we will never see multiple instances of this
326 	 * type of memory controller.  The ID is therefore hardcoded to 0.
327 	 */
328 	if (edac_mc_add_mc(mci)) {
329 		edac_dbg(3, "failed edac_mc_add_mc()\n");
330 		goto fail;
331 	}
332 
333 	/* get this far and it's successful */
334 
335 	if (disable_hardware_scrub) {
336 		edac_dbg(3, "Disabling Hardware Scrub (scrub on error)\n");
337 		pci_write_bits32(pdev, R82600_EAP, BIT(31), BIT(31));
338 	}
339 
340 	/* allocating generic PCI control info */
341 	r82600_pci = edac_pci_create_generic_ctl(&pdev->dev, EDAC_MOD_STR);
342 	if (!r82600_pci) {
343 		printk(KERN_WARNING
344 			"%s(): Unable to create PCI control\n",
345 			__func__);
346 		printk(KERN_WARNING
347 			"%s(): PCI error report via EDAC not setup\n",
348 			__func__);
349 	}
350 
351 	edac_dbg(3, "success\n");
352 	return 0;
353 
354 fail:
355 	edac_mc_free(mci);
356 	return -ENODEV;
357 }
358 
359 /* returns count (>= 0), or negative on error */
360 static int r82600_init_one(struct pci_dev *pdev,
361 			   const struct pci_device_id *ent)
362 {
363 	edac_dbg(0, "\n");
364 
365 	/* don't need to call pci_enable_device() */
366 	return r82600_probe1(pdev, ent->driver_data);
367 }
368 
369 static void r82600_remove_one(struct pci_dev *pdev)
370 {
371 	struct mem_ctl_info *mci;
372 
373 	edac_dbg(0, "\n");
374 
375 	if (r82600_pci)
376 		edac_pci_release_generic_ctl(r82600_pci);
377 
378 	if ((mci = edac_mc_del_mc(&pdev->dev)) == NULL)
379 		return;
380 
381 	edac_mc_free(mci);
382 }
383 
384 static const struct pci_device_id r82600_pci_tbl[] = {
385 	{
386 	 PCI_DEVICE(PCI_VENDOR_ID_RADISYS, R82600_BRIDGE_ID)
387 	 },
388 	{
389 	 0,
390 	 }			/* 0 terminated list. */
391 };
392 
393 MODULE_DEVICE_TABLE(pci, r82600_pci_tbl);
394 
395 static struct pci_driver r82600_driver = {
396 	.name = EDAC_MOD_STR,
397 	.probe = r82600_init_one,
398 	.remove = r82600_remove_one,
399 	.id_table = r82600_pci_tbl,
400 };
401 
402 static int __init r82600_init(void)
403 {
404        /* Ensure that the OPSTATE is set correctly for POLL or NMI */
405        opstate_init();
406 
407 	return pci_register_driver(&r82600_driver);
408 }
409 
410 static void __exit r82600_exit(void)
411 {
412 	pci_unregister_driver(&r82600_driver);
413 }
414 
415 module_init(r82600_init);
416 module_exit(r82600_exit);
417 
418 MODULE_LICENSE("GPL");
419 MODULE_AUTHOR("Tim Small <tim@buttersideup.com> - WPAD Ltd. "
420 		"on behalf of EADS Astrium");
421 MODULE_DESCRIPTION("MC support for Radisys 82600 memory controllers");
422 
423 module_param(disable_hardware_scrub, bool, 0644);
424 MODULE_PARM_DESC(disable_hardware_scrub,
425 		 "If set, disable the chipset's automatic scrub for CEs");
426 
427 module_param(edac_op_state, int, 0444);
428 MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");
429