xref: /openbmc/linux/drivers/edac/r82600_edac.c (revision 9aa2cba7)
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 	r82600_get_error_info(mci, &info);
208 	r82600_process_error_info(mci, &info, 1);
209 }
210 
211 static inline int ecc_enabled(u8 dramcr)
212 {
213 	return dramcr & BIT(5);
214 }
215 
216 static void r82600_init_csrows(struct mem_ctl_info *mci, struct pci_dev *pdev,
217 			u8 dramcr)
218 {
219 	struct csrow_info *csrow;
220 	struct dimm_info *dimm;
221 	int index;
222 	u8 drbar;		/* SDRAM Row Boundary Address Register */
223 	u32 row_high_limit, row_high_limit_last;
224 	u32 reg_sdram, ecc_on, row_base;
225 
226 	ecc_on = ecc_enabled(dramcr);
227 	reg_sdram = dramcr & BIT(4);
228 	row_high_limit_last = 0;
229 
230 	for (index = 0; index < mci->nr_csrows; index++) {
231 		csrow = mci->csrows[index];
232 		dimm = csrow->channels[0]->dimm;
233 
234 		/* find the DRAM Chip Select Base address and mask */
235 		pci_read_config_byte(pdev, R82600_DRBA + index, &drbar);
236 
237 		edac_dbg(1, "Row=%d DRBA = %#0x\n", index, drbar);
238 
239 		row_high_limit = ((u32) drbar << 24);
240 /*		row_high_limit = ((u32)drbar << 24) | 0xffffffUL; */
241 
242 		edac_dbg(1, "Row=%d, Boundary Address=%#0x, Last = %#0x\n",
243 			 index, row_high_limit, row_high_limit_last);
244 
245 		/* Empty row [p.57] */
246 		if (row_high_limit == row_high_limit_last)
247 			continue;
248 
249 		row_base = row_high_limit_last;
250 
251 		csrow->first_page = row_base >> PAGE_SHIFT;
252 		csrow->last_page = (row_high_limit >> PAGE_SHIFT) - 1;
253 
254 		dimm->nr_pages = csrow->last_page - csrow->first_page + 1;
255 		/* Error address is top 19 bits - so granularity is      *
256 		 * 14 bits                                               */
257 		dimm->grain = 1 << 14;
258 		dimm->mtype = reg_sdram ? MEM_RDDR : MEM_DDR;
259 		/* FIXME - check that this is unknowable with this chipset */
260 		dimm->dtype = DEV_UNKNOWN;
261 
262 		/* Mode is global on 82600 */
263 		dimm->edac_mode = ecc_on ? EDAC_SECDED : EDAC_NONE;
264 		row_high_limit_last = row_high_limit;
265 	}
266 }
267 
268 static int r82600_probe1(struct pci_dev *pdev, int dev_idx)
269 {
270 	struct mem_ctl_info *mci;
271 	struct edac_mc_layer layers[2];
272 	u8 dramcr;
273 	u32 eapr;
274 	u32 scrub_disabled;
275 	u32 sdram_refresh_rate;
276 	struct r82600_error_info discard;
277 
278 	edac_dbg(0, "\n");
279 	pci_read_config_byte(pdev, R82600_DRAMC, &dramcr);
280 	pci_read_config_dword(pdev, R82600_EAP, &eapr);
281 	scrub_disabled = eapr & BIT(31);
282 	sdram_refresh_rate = dramcr & (BIT(0) | BIT(1));
283 	edac_dbg(2, "sdram refresh rate = %#0x\n", sdram_refresh_rate);
284 	edac_dbg(2, "DRAMC register = %#0x\n", dramcr);
285 	layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
286 	layers[0].size = R82600_NR_CSROWS;
287 	layers[0].is_virt_csrow = true;
288 	layers[1].type = EDAC_MC_LAYER_CHANNEL;
289 	layers[1].size = R82600_NR_CHANS;
290 	layers[1].is_virt_csrow = false;
291 	mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers, 0);
292 	if (mci == NULL)
293 		return -ENOMEM;
294 
295 	edac_dbg(0, "mci = %p\n", mci);
296 	mci->pdev = &pdev->dev;
297 	mci->mtype_cap = MEM_FLAG_RDDR | MEM_FLAG_DDR;
298 	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
299 	/* FIXME try to work out if the chip leads have been used for COM2
300 	 * instead on this board? [MA6?] MAYBE:
301 	 */
302 
303 	/* On the R82600, the pins for memory bits 72:65 - i.e. the   *
304 	 * EC bits are shared with the pins for COM2 (!), so if COM2  *
305 	 * is enabled, we assume COM2 is wired up, and thus no EDAC   *
306 	 * is possible.                                               */
307 	mci->edac_cap = EDAC_FLAG_NONE | EDAC_FLAG_EC | EDAC_FLAG_SECDED;
308 
309 	if (ecc_enabled(dramcr)) {
310 		if (scrub_disabled)
311 			edac_dbg(3, "mci = %p - Scrubbing disabled! EAP: %#0x\n",
312 				 mci, eapr);
313 	} else
314 		mci->edac_cap = EDAC_FLAG_NONE;
315 
316 	mci->mod_name = EDAC_MOD_STR;
317 	mci->ctl_name = "R82600";
318 	mci->dev_name = pci_name(pdev);
319 	mci->edac_check = r82600_check;
320 	mci->ctl_page_to_phys = NULL;
321 	r82600_init_csrows(mci, pdev, dramcr);
322 	r82600_get_error_info(mci, &discard);	/* clear counters */
323 
324 	/* Here we assume that we will never see multiple instances of this
325 	 * type of memory controller.  The ID is therefore hardcoded to 0.
326 	 */
327 	if (edac_mc_add_mc(mci)) {
328 		edac_dbg(3, "failed edac_mc_add_mc()\n");
329 		goto fail;
330 	}
331 
332 	/* get this far and it's successful */
333 
334 	if (disable_hardware_scrub) {
335 		edac_dbg(3, "Disabling Hardware Scrub (scrub on error)\n");
336 		pci_write_bits32(pdev, R82600_EAP, BIT(31), BIT(31));
337 	}
338 
339 	/* allocating generic PCI control info */
340 	r82600_pci = edac_pci_create_generic_ctl(&pdev->dev, EDAC_MOD_STR);
341 	if (!r82600_pci) {
342 		printk(KERN_WARNING
343 			"%s(): Unable to create PCI control\n",
344 			__func__);
345 		printk(KERN_WARNING
346 			"%s(): PCI error report via EDAC not setup\n",
347 			__func__);
348 	}
349 
350 	edac_dbg(3, "success\n");
351 	return 0;
352 
353 fail:
354 	edac_mc_free(mci);
355 	return -ENODEV;
356 }
357 
358 /* returns count (>= 0), or negative on error */
359 static int r82600_init_one(struct pci_dev *pdev,
360 			   const struct pci_device_id *ent)
361 {
362 	edac_dbg(0, "\n");
363 
364 	/* don't need to call pci_enable_device() */
365 	return r82600_probe1(pdev, ent->driver_data);
366 }
367 
368 static void r82600_remove_one(struct pci_dev *pdev)
369 {
370 	struct mem_ctl_info *mci;
371 
372 	edac_dbg(0, "\n");
373 
374 	if (r82600_pci)
375 		edac_pci_release_generic_ctl(r82600_pci);
376 
377 	if ((mci = edac_mc_del_mc(&pdev->dev)) == NULL)
378 		return;
379 
380 	edac_mc_free(mci);
381 }
382 
383 static const struct pci_device_id r82600_pci_tbl[] = {
384 	{
385 	 PCI_DEVICE(PCI_VENDOR_ID_RADISYS, R82600_BRIDGE_ID)
386 	 },
387 	{
388 	 0,
389 	 }			/* 0 terminated list. */
390 };
391 
392 MODULE_DEVICE_TABLE(pci, r82600_pci_tbl);
393 
394 static struct pci_driver r82600_driver = {
395 	.name = EDAC_MOD_STR,
396 	.probe = r82600_init_one,
397 	.remove = r82600_remove_one,
398 	.id_table = r82600_pci_tbl,
399 };
400 
401 static int __init r82600_init(void)
402 {
403        /* Ensure that the OPSTATE is set correctly for POLL or NMI */
404        opstate_init();
405 
406 	return pci_register_driver(&r82600_driver);
407 }
408 
409 static void __exit r82600_exit(void)
410 {
411 	pci_unregister_driver(&r82600_driver);
412 }
413 
414 module_init(r82600_init);
415 module_exit(r82600_exit);
416 
417 MODULE_LICENSE("GPL");
418 MODULE_AUTHOR("Tim Small <tim@buttersideup.com> - WPAD Ltd. on behalf of EADS Astrium");
419 MODULE_DESCRIPTION("MC support for Radisys 82600 memory controllers");
420 
421 module_param(disable_hardware_scrub, bool, 0644);
422 MODULE_PARM_DESC(disable_hardware_scrub,
423 		 "If set, disable the chipset's automatic scrub for CEs");
424 
425 module_param(edac_op_state, int, 0444);
426 MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");
427