drivers/edac/cpc925_edac.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * cpc925_edac.c, EDAC driver for IBM CPC925 Bridge and Memory Controller.
   4  *
   5  * Copyright (c) 2008 Wind River Systems, Inc.
   6  *
   7  * Authors:     Cao Qingtao <qingtao.cao@windriver.com>
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/io.h>
  13 #include <linux/edac.h>
  14 #include <linux/of.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/gfp.h>
  17
  18 #include "edac_module.h"
  19
  20 #define CPC925_EDAC_REVISION    " Ver: 1.0.0"
  21 #define CPC925_EDAC_MOD_STR     "cpc925_edac"
  22
  23 #define cpc925_printk(level, fmt, arg...) \
  24         edac_printk(level, "CPC925", fmt, ##arg)
  25
  26 #define cpc925_mc_printk(mci, level, fmt, arg...) \
  27         edac_mc_chipset_printk(mci, level, "CPC925", fmt, ##arg)
  28
  29 /*
  30  * CPC925 registers are of 32 bits with bit0 defined at the
  31  * most significant bit and bit31 at that of least significant.
  32  */
  33 #define CPC925_BITS_PER_REG     32
  34 #define CPC925_BIT(nr)          (1UL << (CPC925_BITS_PER_REG - 1 - nr))
  35
  36 /*
  37  * EDAC device names for the error detections of
  38  * CPU Interface and Hypertransport Link.
  39  */
  40 #define CPC925_CPU_ERR_DEV      "cpu"
  41 #define CPC925_HT_LINK_DEV      "htlink"
  42
  43 /* Suppose DDR Refresh cycle is 15.6 microsecond */
  44 #define CPC925_REF_FREQ         0xFA69
  45 #define CPC925_SCRUB_BLOCK_SIZE 64      /* bytes */
  46 #define CPC925_NR_CSROWS        8
  47
  48 /*
  49  * All registers and bits definitions are taken from
  50  * "CPC925 Bridge and Memory Controller User Manual, SA14-2761-02".
  51  */
  52
  53 /*
  54  * CPU and Memory Controller Registers
  55  */
  56 /************************************************************
  57  *      Processor Interface Exception Mask Register (APIMASK)
  58  ************************************************************/
  59 #define REG_APIMASK_OFFSET      0x30070
  60 enum apimask_bits {
  61         APIMASK_DART    = CPC925_BIT(0), /* DART Exception */
  62         APIMASK_ADI0    = CPC925_BIT(1), /* Handshake Error on PI0_ADI */
  63         APIMASK_ADI1    = CPC925_BIT(2), /* Handshake Error on PI1_ADI */
  64         APIMASK_STAT    = CPC925_BIT(3), /* Status Exception */
  65         APIMASK_DERR    = CPC925_BIT(4), /* Data Error Exception */
  66         APIMASK_ADRS0   = CPC925_BIT(5), /* Addressing Exception on PI0 */
  67         APIMASK_ADRS1   = CPC925_BIT(6), /* Addressing Exception on PI1 */
  68                                          /* BIT(7) Reserved */
  69         APIMASK_ECC_UE_H = CPC925_BIT(8), /* UECC upper */
  70         APIMASK_ECC_CE_H = CPC925_BIT(9), /* CECC upper */
  71         APIMASK_ECC_UE_L = CPC925_BIT(10), /* UECC lower */
  72         APIMASK_ECC_CE_L = CPC925_BIT(11), /* CECC lower */
  73
  74         CPU_MASK_ENABLE = (APIMASK_DART | APIMASK_ADI0 | APIMASK_ADI1 |
  75                            APIMASK_STAT | APIMASK_DERR | APIMASK_ADRS0 |
  76                            APIMASK_ADRS1),
  77         ECC_MASK_ENABLE = (APIMASK_ECC_UE_H | APIMASK_ECC_CE_H |
  78                            APIMASK_ECC_UE_L | APIMASK_ECC_CE_L),
  79 };
  80 #define APIMASK_ADI(n)          CPC925_BIT(((n)+1))
  81
  82 /************************************************************
  83  *      Processor Interface Exception Register (APIEXCP)
  84  ************************************************************/
  85 #define REG_APIEXCP_OFFSET      0x30060
  86 enum apiexcp_bits {
  87         APIEXCP_DART    = CPC925_BIT(0), /* DART Exception */
  88         APIEXCP_ADI0    = CPC925_BIT(1), /* Handshake Error on PI0_ADI */
  89         APIEXCP_ADI1    = CPC925_BIT(2), /* Handshake Error on PI1_ADI */
  90         APIEXCP_STAT    = CPC925_BIT(3), /* Status Exception */
  91         APIEXCP_DERR    = CPC925_BIT(4), /* Data Error Exception */
  92         APIEXCP_ADRS0   = CPC925_BIT(5), /* Addressing Exception on PI0 */
  93         APIEXCP_ADRS1   = CPC925_BIT(6), /* Addressing Exception on PI1 */
  94                                          /* BIT(7) Reserved */
  95         APIEXCP_ECC_UE_H = CPC925_BIT(8), /* UECC upper */
  96         APIEXCP_ECC_CE_H = CPC925_BIT(9), /* CECC upper */
  97         APIEXCP_ECC_UE_L = CPC925_BIT(10), /* UECC lower */
  98         APIEXCP_ECC_CE_L = CPC925_BIT(11), /* CECC lower */
  99
 100         CPU_EXCP_DETECTED = (APIEXCP_DART | APIEXCP_ADI0 | APIEXCP_ADI1 |
 101                              APIEXCP_STAT | APIEXCP_DERR | APIEXCP_ADRS0 |
 102                              APIEXCP_ADRS1),
 103         UECC_EXCP_DETECTED = (APIEXCP_ECC_UE_H | APIEXCP_ECC_UE_L),
 104         CECC_EXCP_DETECTED = (APIEXCP_ECC_CE_H | APIEXCP_ECC_CE_L),
 105         ECC_EXCP_DETECTED = (UECC_EXCP_DETECTED | CECC_EXCP_DETECTED),
 106 };
 107
 108 /************************************************************
 109  *      Memory Bus Configuration Register (MBCR)
 110 ************************************************************/
 111 #define REG_MBCR_OFFSET         0x2190
 112 #define MBCR_64BITCFG_SHIFT     23
 113 #define MBCR_64BITCFG_MASK      (1UL << MBCR_64BITCFG_SHIFT)
 114 #define MBCR_64BITBUS_SHIFT     22
 115 #define MBCR_64BITBUS_MASK      (1UL << MBCR_64BITBUS_SHIFT)
 116
 117 /************************************************************
 118  *      Memory Bank Mode Register (MBMR)
 119 ************************************************************/
 120 #define REG_MBMR_OFFSET         0x21C0
 121 #define MBMR_MODE_MAX_VALUE     0xF
 122 #define MBMR_MODE_SHIFT         25
 123 #define MBMR_MODE_MASK          (MBMR_MODE_MAX_VALUE << MBMR_MODE_SHIFT)
 124 #define MBMR_BBA_SHIFT          24
 125 #define MBMR_BBA_MASK           (1UL << MBMR_BBA_SHIFT)
 126
 127 /************************************************************
 128  *      Memory Bank Boundary Address Register (MBBAR)
 129  ************************************************************/
 130 #define REG_MBBAR_OFFSET        0x21D0
 131 #define MBBAR_BBA_MAX_VALUE     0xFF
 132 #define MBBAR_BBA_SHIFT         24
 133 #define MBBAR_BBA_MASK          (MBBAR_BBA_MAX_VALUE << MBBAR_BBA_SHIFT)
 134
 135 /************************************************************
 136  *      Memory Scrub Control Register (MSCR)
 137  ************************************************************/
 138 #define REG_MSCR_OFFSET         0x2400
 139 #define MSCR_SCRUB_MOD_MASK     0xC0000000 /* scrub_mod - bit0:1*/
 140 #define MSCR_BACKGR_SCRUB       0x40000000 /* 01 */
 141 #define MSCR_SI_SHIFT           16      /* si - bit8:15*/
 142 #define MSCR_SI_MAX_VALUE       0xFF
 143 #define MSCR_SI_MASK            (MSCR_SI_MAX_VALUE << MSCR_SI_SHIFT)
 144
 145 /************************************************************
 146  *      Memory Scrub Range Start Register (MSRSR)
 147  ************************************************************/
 148 #define REG_MSRSR_OFFSET        0x2410
 149
 150 /************************************************************
 151  *      Memory Scrub Range End Register (MSRER)
 152  ************************************************************/
 153 #define REG_MSRER_OFFSET        0x2420
 154
 155 /************************************************************
 156  *      Memory Scrub Pattern Register (MSPR)
 157  ************************************************************/
 158 #define REG_MSPR_OFFSET         0x2430
 159
 160 /************************************************************
 161  *      Memory Check Control Register (MCCR)
 162  ************************************************************/
 163 #define REG_MCCR_OFFSET         0x2440
 164 enum mccr_bits {
 165         MCCR_ECC_EN     = CPC925_BIT(0), /* ECC high and low check */
 166 };
 167
 168 /************************************************************
 169  *      Memory Check Range End Register (MCRER)
 170  ************************************************************/
 171 #define REG_MCRER_OFFSET        0x2450
 172
 173 /************************************************************
 174  *      Memory Error Address Register (MEAR)
 175  ************************************************************/
 176 #define REG_MEAR_OFFSET         0x2460
 177 #define MEAR_BCNT_MAX_VALUE     0x3
 178 #define MEAR_BCNT_SHIFT         30
 179 #define MEAR_BCNT_MASK          (MEAR_BCNT_MAX_VALUE << MEAR_BCNT_SHIFT)
 180 #define MEAR_RANK_MAX_VALUE     0x7
 181 #define MEAR_RANK_SHIFT         27
 182 #define MEAR_RANK_MASK          (MEAR_RANK_MAX_VALUE << MEAR_RANK_SHIFT)
 183 #define MEAR_COL_MAX_VALUE      0x7FF
 184 #define MEAR_COL_SHIFT          16
 185 #define MEAR_COL_MASK           (MEAR_COL_MAX_VALUE << MEAR_COL_SHIFT)
 186 #define MEAR_BANK_MAX_VALUE     0x3
 187 #define MEAR_BANK_SHIFT         14
 188 #define MEAR_BANK_MASK          (MEAR_BANK_MAX_VALUE << MEAR_BANK_SHIFT)
 189 #define MEAR_ROW_MASK           0x00003FFF
 190
 191 /************************************************************
 192  *      Memory Error Syndrome Register (MESR)
 193  ************************************************************/
 194 #define REG_MESR_OFFSET         0x2470
 195 #define MESR_ECC_SYN_H_MASK     0xFF00
 196 #define MESR_ECC_SYN_L_MASK     0x00FF
 197
 198 /************************************************************
 199  *      Memory Mode Control Register (MMCR)
 200  ************************************************************/
 201 #define REG_MMCR_OFFSET         0x2500
 202 enum mmcr_bits {
 203         MMCR_REG_DIMM_MODE = CPC925_BIT(3),
 204 };
 205
 206 /*
 207  * HyperTransport Link Registers
 208  */
 209 /************************************************************
 210  *  Error Handling/Enumeration Scratch Pad Register (ERRCTRL)
 211  ************************************************************/
 212 #define REG_ERRCTRL_OFFSET      0x70140
 213 enum errctrl_bits {                      /* nonfatal interrupts for */
 214         ERRCTRL_SERR_NF = CPC925_BIT(0), /* system error */
 215         ERRCTRL_CRC_NF  = CPC925_BIT(1), /* CRC error */
 216         ERRCTRL_RSP_NF  = CPC925_BIT(2), /* Response error */
 217         ERRCTRL_EOC_NF  = CPC925_BIT(3), /* End-Of-Chain error */
 218         ERRCTRL_OVF_NF  = CPC925_BIT(4), /* Overflow error */
 219         ERRCTRL_PROT_NF = CPC925_BIT(5), /* Protocol error */
 220
 221         ERRCTRL_RSP_ERR = CPC925_BIT(6), /* Response error received */
 222         ERRCTRL_CHN_FAL = CPC925_BIT(7), /* Sync flooding detected */
 223
 224         HT_ERRCTRL_ENABLE = (ERRCTRL_SERR_NF | ERRCTRL_CRC_NF |
 225                              ERRCTRL_RSP_NF | ERRCTRL_EOC_NF |
 226                              ERRCTRL_OVF_NF | ERRCTRL_PROT_NF),
 227         HT_ERRCTRL_DETECTED = (ERRCTRL_RSP_ERR | ERRCTRL_CHN_FAL),
 228 };
 229
 230 /************************************************************
 231  *  Link Configuration and Link Control Register (LINKCTRL)
 232  ************************************************************/
 233 #define REG_LINKCTRL_OFFSET     0x70110
 234 enum linkctrl_bits {
 235         LINKCTRL_CRC_ERR        = (CPC925_BIT(22) | CPC925_BIT(23)),
 236         LINKCTRL_LINK_FAIL      = CPC925_BIT(27),
 237
 238         HT_LINKCTRL_DETECTED    = (LINKCTRL_CRC_ERR | LINKCTRL_LINK_FAIL),
 239 };
 240
 241 /************************************************************
 242  *  Link FreqCap/Error/Freq/Revision ID Register (LINKERR)
 243  ************************************************************/
 244 #define REG_LINKERR_OFFSET      0x70120
 245 enum linkerr_bits {
 246         LINKERR_EOC_ERR         = CPC925_BIT(17), /* End-Of-Chain error */
 247         LINKERR_OVF_ERR         = CPC925_BIT(18), /* Receive Buffer Overflow */
 248         LINKERR_PROT_ERR        = CPC925_BIT(19), /* Protocol error */
 249
 250         HT_LINKERR_DETECTED     = (LINKERR_EOC_ERR | LINKERR_OVF_ERR |
 251                                    LINKERR_PROT_ERR),
 252 };
 253
 254 /************************************************************
 255  *      Bridge Control Register (BRGCTRL)
 256  ************************************************************/
 257 #define REG_BRGCTRL_OFFSET      0x70300
 258 enum brgctrl_bits {
 259         BRGCTRL_DETSERR = CPC925_BIT(0), /* SERR on Secondary Bus */
 260         BRGCTRL_SECBUSRESET = CPC925_BIT(9), /* Secondary Bus Reset */
 261 };
 262
 263 /* Private structure for edac memory controller */
 264 struct cpc925_mc_pdata {
 265         void __iomem *vbase;
 266         unsigned long total_mem;
 267         const char *name;
 268         int edac_idx;
 269 };
 270
 271 /* Private structure for common edac device */
 272 struct cpc925_dev_info {
 273         void __iomem *vbase;
 274         struct platform_device *pdev;
 275         char *ctl_name;
 276         int edac_idx;
 277         struct edac_device_ctl_info *edac_dev;
 278         void (*init)(struct cpc925_dev_info *dev_info);
 279         void (*exit)(struct cpc925_dev_info *dev_info);
 280         void (*check)(struct edac_device_ctl_info *edac_dev);
 281 };
 282
 283 /* Get total memory size from Open Firmware DTB */
 284 static void get_total_mem(struct cpc925_mc_pdata *pdata)
 285 {
 286         struct device_node *np = NULL;
 287         const unsigned int *reg, *reg_end;
 288         int len, sw, aw;
 289         unsigned long start, size;
 290
 291         np = of_find_node_by_type(NULL, "memory");
 292         if (!np)
 293                 return;
 294
 295         aw = of_n_addr_cells(np);
 296         sw = of_n_size_cells(np);
 297         reg = (const unsigned int *)of_get_property(np, "reg", &len);
 298         reg_end = reg + len/4;
 299
 300         pdata->total_mem = 0;
 301         do {
 302                 start = of_read_number(reg, aw);
 303                 reg += aw;
 304                 size = of_read_number(reg, sw);
 305                 reg += sw;
 306                 edac_dbg(1, "start 0x%lx, size 0x%lx\n", start, size);
 307                 pdata->total_mem += size;
 308         } while (reg < reg_end);
 309
 310         of_node_put(np);
 311         edac_dbg(0, "total_mem 0x%lx\n", pdata->total_mem);
 312 }
 313
 314 static void cpc925_init_csrows(struct mem_ctl_info *mci)
 315 {
 316         struct cpc925_mc_pdata *pdata = mci->pvt_info;
 317         struct csrow_info *csrow;
 318         struct dimm_info *dimm;
 319         enum dev_type dtype;
 320         int index, j;
 321         u32 mbmr, mbbar, bba, grain;
 322         unsigned long row_size, nr_pages, last_nr_pages = 0;
 323
 324         get_total_mem(pdata);
 325
 326         for (index = 0; index < mci->nr_csrows; index++) {
 327                 mbmr = __raw_readl(pdata->vbase + REG_MBMR_OFFSET +
 328                                    0x20 * index);
 329                 mbbar = __raw_readl(pdata->vbase + REG_MBBAR_OFFSET +
 330                                    0x20 + index);
 331                 bba = (((mbmr & MBMR_BBA_MASK) >> MBMR_BBA_SHIFT) << 8) |
 332                        ((mbbar & MBBAR_BBA_MASK) >> MBBAR_BBA_SHIFT);
 333
 334                 if (bba == 0)
 335                         continue; /* not populated */
 336
 337                 csrow = mci->csrows[index];
 338
 339                 row_size = bba * (1UL << 28);   /* 256M */
 340                 csrow->first_page = last_nr_pages;
 341                 nr_pages = row_size >> PAGE_SHIFT;
 342                 csrow->last_page = csrow->first_page + nr_pages - 1;
 343                 last_nr_pages = csrow->last_page + 1;
 344
 345                 switch (csrow->nr_channels) {
 346                 case 1: /* Single channel */
 347                         grain = 32; /* four-beat burst of 32 bytes */
 348                         break;
 349                 case 2: /* Dual channel */
 350                 default:
 351                         grain = 64; /* four-beat burst of 64 bytes */
 352                         break;
 353                 }
 354                 switch ((mbmr & MBMR_MODE_MASK) >> MBMR_MODE_SHIFT) {
 355                 case 6: /* 0110, no way to differentiate X8 VS X16 */
 356                 case 5: /* 0101 */
 357                 case 8: /* 1000 */
 358                         dtype = DEV_X16;
 359                         break;
 360                 case 7: /* 0111 */
 361                 case 9: /* 1001 */
 362                         dtype = DEV_X8;
 363                         break;
 364                 default:
 365                         dtype = DEV_UNKNOWN;
 366                 break;
 367                 }
 368                 for (j = 0; j < csrow->nr_channels; j++) {
 369                         dimm = csrow->channels[j]->dimm;
 370                         dimm->nr_pages = nr_pages / csrow->nr_channels;
 371                         dimm->mtype = MEM_RDDR;
 372                         dimm->edac_mode = EDAC_SECDED;
 373                         dimm->grain = grain;
 374                         dimm->dtype = dtype;
 375                 }
 376         }
 377 }
 378
 379 /* Enable memory controller ECC detection */
 380 static void cpc925_mc_init(struct mem_ctl_info *mci)
 381 {
 382         struct cpc925_mc_pdata *pdata = mci->pvt_info;
 383         u32 apimask;
 384         u32 mccr;
 385
 386         /* Enable various ECC error exceptions */
 387         apimask = __raw_readl(pdata->vbase + REG_APIMASK_OFFSET);
 388         if ((apimask & ECC_MASK_ENABLE) == 0) {
 389                 apimask |= ECC_MASK_ENABLE;
 390                 __raw_writel(apimask, pdata->vbase + REG_APIMASK_OFFSET);
 391         }
 392
 393         /* Enable ECC detection */
 394         mccr = __raw_readl(pdata->vbase + REG_MCCR_OFFSET);
 395         if ((mccr & MCCR_ECC_EN) == 0) {
 396                 mccr |= MCCR_ECC_EN;
 397                 __raw_writel(mccr, pdata->vbase + REG_MCCR_OFFSET);
 398         }
 399 }
 400
 401 /* Disable memory controller ECC detection */
 402 static void cpc925_mc_exit(struct mem_ctl_info *mci)
 403 {
 404         /*
 405          * WARNING:
 406          * We are supposed to clear the ECC error detection bits,
 407          * and it will be no problem to do so. However, once they
 408          * are cleared here if we want to re-install CPC925 EDAC
 409          * module later, setting them up in cpc925_mc_init() will
 410          * trigger machine check exception.
 411          * Also, it's ok to leave ECC error detection bits enabled,
 412          * since they are reset to 1 by default or by boot loader.
 413          */
 414
 415         return;
 416 }
 417
 418 /*
 419  * Revert DDR column/row/bank addresses into page frame number and
 420  * offset in page.
 421  *
 422  * Suppose memory mode is 0x0111(128-bit mode, identical DIMM pairs),
 423  * physical address(PA) bits to column address(CA) bits mappings are:
 424  * CA   0   1   2   3   4   5   6   7   8   9   10
 425  * PA   59  58  57  56  55  54  53  52  51  50  49
 426  *
 427  * physical address(PA) bits to bank address(BA) bits mappings are:
 428  * BA   0   1
 429  * PA   43  44
 430  *
 431  * physical address(PA) bits to row address(RA) bits mappings are:
 432  * RA   0   1   2   3   4   5   6   7   8   9   10   11   12
 433  * PA   36  35  34  48  47  46  45  40  41  42  39   38   37
 434  */
 435 static void cpc925_mc_get_pfn(struct mem_ctl_info *mci, u32 mear,
 436                 unsigned long *pfn, unsigned long *offset, int *csrow)
 437 {
 438         u32 bcnt, rank, col, bank, row;
 439         u32 c;
 440         unsigned long pa;
 441         int i;
 442
 443         bcnt = (mear & MEAR_BCNT_MASK) >> MEAR_BCNT_SHIFT;
 444         rank = (mear & MEAR_RANK_MASK) >> MEAR_RANK_SHIFT;
 445         col = (mear & MEAR_COL_MASK) >> MEAR_COL_SHIFT;
 446         bank = (mear & MEAR_BANK_MASK) >> MEAR_BANK_SHIFT;
 447         row = mear & MEAR_ROW_MASK;
 448
 449         *csrow = rank;
 450
 451 #ifdef CONFIG_EDAC_DEBUG
 452         if (mci->csrows[rank]->first_page == 0) {
 453                 cpc925_mc_printk(mci, KERN_ERR, "ECC occurs in a "
 454                         "non-populated csrow, broken hardware?\n");
 455                 return;
 456         }
 457 #endif
 458
 459         /* Revert csrow number */
 460         pa = mci->csrows[rank]->first_page << PAGE_SHIFT;
 461
 462         /* Revert column address */
 463         col += bcnt;
 464         for (i = 0; i < 11; i++) {
 465                 c = col & 0x1;
 466                 col >>= 1;
 467                 pa |= c << (14 - i);
 468         }
 469
 470         /* Revert bank address */
 471         pa |= bank << 19;
 472
 473         /* Revert row address, in 4 steps */
 474         for (i = 0; i < 3; i++) {
 475                 c = row & 0x1;
 476                 row >>= 1;
 477                 pa |= c << (26 - i);
 478         }
 479
 480         for (i = 0; i < 3; i++) {
 481                 c = row & 0x1;
 482                 row >>= 1;
 483                 pa |= c << (21 + i);
 484         }
 485
 486         for (i = 0; i < 4; i++) {
 487                 c = row & 0x1;
 488                 row >>= 1;
 489                 pa |= c << (18 - i);
 490         }
 491
 492         for (i = 0; i < 3; i++) {
 493                 c = row & 0x1;
 494                 row >>= 1;
 495                 pa |= c << (29 - i);
 496         }
 497
 498         *offset = pa & (PAGE_SIZE - 1);
 499         *pfn = pa >> PAGE_SHIFT;
 500
 501         edac_dbg(0, "ECC physical address 0x%lx\n", pa);
 502 }
 503
 504 static int cpc925_mc_find_channel(struct mem_ctl_info *mci, u16 syndrome)
 505 {
 506         if ((syndrome & MESR_ECC_SYN_H_MASK) == 0)
 507                 return 0;
 508
 509         if ((syndrome & MESR_ECC_SYN_L_MASK) == 0)
 510                 return 1;
 511
 512         cpc925_mc_printk(mci, KERN_INFO, "Unexpected syndrome value: 0x%x\n",
 513                          syndrome);
 514         return 1;
 515 }
 516
 517 /* Check memory controller registers for ECC errors */
 518 static void cpc925_mc_check(struct mem_ctl_info *mci)
 519 {
 520         struct cpc925_mc_pdata *pdata = mci->pvt_info;
 521         u32 apiexcp;
 522         u32 mear;
 523         u32 mesr;
 524         u16 syndrome;
 525         unsigned long pfn = 0, offset = 0;
 526         int csrow = 0, channel = 0;
 527
 528         /* APIEXCP is cleared when read */
 529         apiexcp = __raw_readl(pdata->vbase + REG_APIEXCP_OFFSET);
 530         if ((apiexcp & ECC_EXCP_DETECTED) == 0)
 531                 return;
 532
 533         mesr = __raw_readl(pdata->vbase + REG_MESR_OFFSET);
 534         syndrome = mesr | (MESR_ECC_SYN_H_MASK | MESR_ECC_SYN_L_MASK);
 535
 536         mear = __raw_readl(pdata->vbase + REG_MEAR_OFFSET);
 537
 538         /* Revert column/row addresses into page frame number, etc */
 539         cpc925_mc_get_pfn(mci, mear, &pfn, &offset, &csrow);
 540
 541         if (apiexcp & CECC_EXCP_DETECTED) {
 542                 cpc925_mc_printk(mci, KERN_INFO, "DRAM CECC Fault\n");
 543                 channel = cpc925_mc_find_channel(mci, syndrome);
 544                 edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, 1,
 545                                      pfn, offset, syndrome,
 546                                      csrow, channel, -1,
 547                                      mci->ctl_name, "");
 548         }
 549
 550         if (apiexcp & UECC_EXCP_DETECTED) {
 551                 cpc925_mc_printk(mci, KERN_INFO, "DRAM UECC Fault\n");
 552                 edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 1,
 553                                      pfn, offset, 0,
 554                                      csrow, -1, -1,
 555                                      mci->ctl_name, "");
 556         }
 557
 558         cpc925_mc_printk(mci, KERN_INFO, "Dump registers:\n");
 559         cpc925_mc_printk(mci, KERN_INFO, "APIMASK               0x%08x\n",
 560                 __raw_readl(pdata->vbase + REG_APIMASK_OFFSET));
 561         cpc925_mc_printk(mci, KERN_INFO, "APIEXCP               0x%08x\n",
 562                 apiexcp);
 563         cpc925_mc_printk(mci, KERN_INFO, "Mem Scrub Ctrl        0x%08x\n",
 564                 __raw_readl(pdata->vbase + REG_MSCR_OFFSET));
 565         cpc925_mc_printk(mci, KERN_INFO, "Mem Scrub Rge Start   0x%08x\n",
 566                 __raw_readl(pdata->vbase + REG_MSRSR_OFFSET));
 567         cpc925_mc_printk(mci, KERN_INFO, "Mem Scrub Rge End     0x%08x\n",
 568                 __raw_readl(pdata->vbase + REG_MSRER_OFFSET));
 569         cpc925_mc_printk(mci, KERN_INFO, "Mem Scrub Pattern     0x%08x\n",
 570                 __raw_readl(pdata->vbase + REG_MSPR_OFFSET));
 571         cpc925_mc_printk(mci, KERN_INFO, "Mem Chk Ctrl          0x%08x\n",
 572                 __raw_readl(pdata->vbase + REG_MCCR_OFFSET));
 573         cpc925_mc_printk(mci, KERN_INFO, "Mem Chk Rge End       0x%08x\n",
 574                 __raw_readl(pdata->vbase + REG_MCRER_OFFSET));
 575         cpc925_mc_printk(mci, KERN_INFO, "Mem Err Address       0x%08x\n",
 576                 mesr);
 577         cpc925_mc_printk(mci, KERN_INFO, "Mem Err Syndrome      0x%08x\n",
 578                 syndrome);
 579 }
 580
 581 /******************** CPU err device********************************/
 582 static u32 cpc925_cpu_mask_disabled(void)
 583 {
 584         struct device_node *cpunode;
 585         static u32 mask = 0;
 586
 587         /* use cached value if available */
 588         if (mask != 0)
 589                 return mask;
 590
 591         mask = APIMASK_ADI0 | APIMASK_ADI1;
 592
 593         for_each_of_cpu_node(cpunode) {
 594                 const u32 *reg = of_get_property(cpunode, "reg", NULL);
 595                 if (reg == NULL || *reg > 2) {
 596                         cpc925_printk(KERN_ERR, "Bad reg value at %pOF\n", cpunode);
 597                         continue;
 598                 }
 599
 600                 mask &= ~APIMASK_ADI(*reg);
 601         }
 602
 603         if (mask != (APIMASK_ADI0 | APIMASK_ADI1)) {
 604                 /* We assume that each CPU sits on it's own PI and that
 605                  * for present CPUs the reg property equals to the PI
 606                  * interface id */
 607                 cpc925_printk(KERN_WARNING,
 608                                 "Assuming PI id is equal to CPU MPIC id!\n");
 609         }
 610
 611         return mask;
 612 }
 613
 614 /* Enable CPU Errors detection */
 615 static void cpc925_cpu_init(struct cpc925_dev_info *dev_info)
 616 {
 617         u32 apimask;
 618         u32 cpumask;
 619
 620         apimask = __raw_readl(dev_info->vbase + REG_APIMASK_OFFSET);
 621
 622         cpumask = cpc925_cpu_mask_disabled();
 623         if (apimask & cpumask) {
 624                 cpc925_printk(KERN_WARNING, "CPU(s) not present, "
 625                                 "but enabled in APIMASK, disabling\n");
 626                 apimask &= ~cpumask;
 627         }
 628
 629         if ((apimask & CPU_MASK_ENABLE) == 0)
 630                 apimask |= CPU_MASK_ENABLE;
 631
 632         __raw_writel(apimask, dev_info->vbase + REG_APIMASK_OFFSET);
 633 }
 634
 635 /* Disable CPU Errors detection */
 636 static void cpc925_cpu_exit(struct cpc925_dev_info *dev_info)
 637 {
 638         /*
 639          * WARNING:
 640          * We are supposed to clear the CPU error detection bits,
 641          * and it will be no problem to do so. However, once they
 642          * are cleared here if we want to re-install CPC925 EDAC
 643          * module later, setting them up in cpc925_cpu_init() will
 644          * trigger machine check exception.
 645          * Also, it's ok to leave CPU error detection bits enabled,
 646          * since they are reset to 1 by default.
 647          */
 648
 649         return;
 650 }
 651
 652 /* Check for CPU Errors */
 653 static void cpc925_cpu_check(struct edac_device_ctl_info *edac_dev)
 654 {
 655         struct cpc925_dev_info *dev_info = edac_dev->pvt_info;
 656         u32 apiexcp;
 657         u32 apimask;
 658
 659         /* APIEXCP is cleared when read */
 660         apiexcp = __raw_readl(dev_info->vbase + REG_APIEXCP_OFFSET);
 661         if ((apiexcp & CPU_EXCP_DETECTED) == 0)
 662                 return;
 663
 664         if ((apiexcp & ~cpc925_cpu_mask_disabled()) == 0)
 665                 return;
 666
 667         apimask = __raw_readl(dev_info->vbase + REG_APIMASK_OFFSET);
 668         cpc925_printk(KERN_INFO, "Processor Interface Fault\n"
 669                                  "Processor Interface register dump:\n");
 670         cpc925_printk(KERN_INFO, "APIMASK               0x%08x\n", apimask);
 671         cpc925_printk(KERN_INFO, "APIEXCP               0x%08x\n", apiexcp);
 672
 673         edac_device_handle_ue(edac_dev, 0, 0, edac_dev->ctl_name);
 674 }
 675
 676 /******************** HT Link err device****************************/
 677 /* Enable HyperTransport Link Error detection */
 678 static void cpc925_htlink_init(struct cpc925_dev_info *dev_info)
 679 {
 680         u32 ht_errctrl;
 681
 682         ht_errctrl = __raw_readl(dev_info->vbase + REG_ERRCTRL_OFFSET);
 683         if ((ht_errctrl & HT_ERRCTRL_ENABLE) == 0) {
 684                 ht_errctrl |= HT_ERRCTRL_ENABLE;
 685                 __raw_writel(ht_errctrl, dev_info->vbase + REG_ERRCTRL_OFFSET);
 686         }
 687 }
 688
 689 /* Disable HyperTransport Link Error detection */
 690 static void cpc925_htlink_exit(struct cpc925_dev_info *dev_info)
 691 {
 692         u32 ht_errctrl;
 693
 694         ht_errctrl = __raw_readl(dev_info->vbase + REG_ERRCTRL_OFFSET);
 695         ht_errctrl &= ~HT_ERRCTRL_ENABLE;
 696         __raw_writel(ht_errctrl, dev_info->vbase + REG_ERRCTRL_OFFSET);
 697 }
 698
 699 /* Check for HyperTransport Link errors */
 700 static void cpc925_htlink_check(struct edac_device_ctl_info *edac_dev)
 701 {
 702         struct cpc925_dev_info *dev_info = edac_dev->pvt_info;
 703         u32 brgctrl = __raw_readl(dev_info->vbase + REG_BRGCTRL_OFFSET);
 704         u32 linkctrl = __raw_readl(dev_info->vbase + REG_LINKCTRL_OFFSET);
 705         u32 errctrl = __raw_readl(dev_info->vbase + REG_ERRCTRL_OFFSET);
 706         u32 linkerr = __raw_readl(dev_info->vbase + REG_LINKERR_OFFSET);
 707
 708         if (!((brgctrl & BRGCTRL_DETSERR) ||
 709               (linkctrl & HT_LINKCTRL_DETECTED) ||
 710               (errctrl & HT_ERRCTRL_DETECTED) ||
 711               (linkerr & HT_LINKERR_DETECTED)))
 712                 return;
 713
 714         cpc925_printk(KERN_INFO, "HT Link Fault\n"
 715                                  "HT register dump:\n");
 716         cpc925_printk(KERN_INFO, "Bridge Ctrl                   0x%08x\n",
 717                       brgctrl);
 718         cpc925_printk(KERN_INFO, "Link Config Ctrl              0x%08x\n",
 719                       linkctrl);
 720         cpc925_printk(KERN_INFO, "Error Enum and Ctrl           0x%08x\n",
 721                       errctrl);
 722         cpc925_printk(KERN_INFO, "Link Error                    0x%08x\n",
 723                       linkerr);
 724
 725         /* Clear by write 1 */
 726         if (brgctrl & BRGCTRL_DETSERR)
 727                 __raw_writel(BRGCTRL_DETSERR,
 728                                 dev_info->vbase + REG_BRGCTRL_OFFSET);
 729
 730         if (linkctrl & HT_LINKCTRL_DETECTED)
 731                 __raw_writel(HT_LINKCTRL_DETECTED,
 732                                 dev_info->vbase + REG_LINKCTRL_OFFSET);
 733
 734         /* Initiate Secondary Bus Reset to clear the chain failure */
 735         if (errctrl & ERRCTRL_CHN_FAL)
 736                 __raw_writel(BRGCTRL_SECBUSRESET,
 737                                 dev_info->vbase + REG_BRGCTRL_OFFSET);
 738
 739         if (errctrl & ERRCTRL_RSP_ERR)
 740                 __raw_writel(ERRCTRL_RSP_ERR,
 741                                 dev_info->vbase + REG_ERRCTRL_OFFSET);
 742
 743         if (linkerr & HT_LINKERR_DETECTED)
 744                 __raw_writel(HT_LINKERR_DETECTED,
 745                                 dev_info->vbase + REG_LINKERR_OFFSET);
 746
 747         edac_device_handle_ce(edac_dev, 0, 0, edac_dev->ctl_name);
 748 }
 749
 750 static struct cpc925_dev_info cpc925_devs[] = {
 751         {
 752         .ctl_name = CPC925_CPU_ERR_DEV,
 753         .init = cpc925_cpu_init,
 754         .exit = cpc925_cpu_exit,
 755         .check = cpc925_cpu_check,
 756         },
 757         {
 758         .ctl_name = CPC925_HT_LINK_DEV,
 759         .init = cpc925_htlink_init,
 760         .exit = cpc925_htlink_exit,
 761         .check = cpc925_htlink_check,
 762         },
 763         { }
 764 };
 765
 766 /*
 767  * Add CPU Err detection and HyperTransport Link Err detection
 768  * as common "edac_device", they have no corresponding device
 769  * nodes in the Open Firmware DTB and we have to add platform
 770  * devices for them. Also, they will share the MMIO with that
 771  * of memory controller.
 772  */
 773 static void cpc925_add_edac_devices(void __iomem *vbase)
 774 {
 775         struct cpc925_dev_info *dev_info;
 776
 777         if (!vbase) {
 778                 cpc925_printk(KERN_ERR, "MMIO not established yet\n");
 779                 return;
 780         }
 781
 782         for (dev_info = &cpc925_devs[0]; dev_info->init; dev_info++) {
 783                 dev_info->vbase = vbase;
 784                 dev_info->pdev = platform_device_register_simple(
 785                                         dev_info->ctl_name, 0, NULL, 0);
 786                 if (IS_ERR(dev_info->pdev)) {
 787                         cpc925_printk(KERN_ERR,
 788                                 "Can't register platform device for %s\n",
 789                                 dev_info->ctl_name);
 790                         continue;
 791                 }
 792
 793                 /*
 794                  * Don't have to allocate private structure but
 795                  * make use of cpc925_devs[] instead.
 796                  */
 797                 dev_info->edac_idx = edac_device_alloc_index();
 798                 dev_info->edac_dev =
 799                         edac_device_alloc_ctl_info(0, dev_info->ctl_name,
 800                                 1, NULL, 0, 0, NULL, 0, dev_info->edac_idx);
 801                 if (!dev_info->edac_dev) {
 802                         cpc925_printk(KERN_ERR, "No memory for edac device\n");
 803                         goto err1;
 804                 }
 805
 806                 dev_info->edac_dev->pvt_info = dev_info;
 807                 dev_info->edac_dev->dev = &dev_info->pdev->dev;
 808                 dev_info->edac_dev->ctl_name = dev_info->ctl_name;
 809                 dev_info->edac_dev->mod_name = CPC925_EDAC_MOD_STR;
 810                 dev_info->edac_dev->dev_name = dev_name(&dev_info->pdev->dev);
 811
 812                 if (edac_op_state == EDAC_OPSTATE_POLL)
 813                         dev_info->edac_dev->edac_check = dev_info->check;
 814
 815                 if (dev_info->init)
 816                         dev_info->init(dev_info);
 817
 818                 if (edac_device_add_device(dev_info->edac_dev) > 0) {
 819                         cpc925_printk(KERN_ERR,
 820                                 "Unable to add edac device for %s\n",
 821                                 dev_info->ctl_name);
 822                         goto err2;
 823                 }
 824
 825                 edac_dbg(0, "Successfully added edac device for %s\n",
 826                          dev_info->ctl_name);
 827
 828                 continue;
 829
 830 err2:
 831                 if (dev_info->exit)
 832                         dev_info->exit(dev_info);
 833                 edac_device_free_ctl_info(dev_info->edac_dev);
 834 err1:
 835                 platform_device_unregister(dev_info->pdev);
 836         }
 837 }
 838
 839 /*
 840  * Delete the common "edac_device" for CPU Err Detection
 841  * and HyperTransport Link Err Detection
 842  */
 843 static void cpc925_del_edac_devices(void)
 844 {
 845         struct cpc925_dev_info *dev_info;
 846
 847         for (dev_info = &cpc925_devs[0]; dev_info->init; dev_info++) {
 848                 if (dev_info->edac_dev) {
 849                         edac_device_del_device(dev_info->edac_dev->dev);
 850                         edac_device_free_ctl_info(dev_info->edac_dev);
 851                         platform_device_unregister(dev_info->pdev);
 852                 }
 853
 854                 if (dev_info->exit)
 855                         dev_info->exit(dev_info);
 856
 857                 edac_dbg(0, "Successfully deleted edac device for %s\n",
 858                          dev_info->ctl_name);
 859         }
 860 }
 861
 862 /* Convert current back-ground scrub rate into byte/sec bandwidth */
 863 static int cpc925_get_sdram_scrub_rate(struct mem_ctl_info *mci)
 864 {
 865         struct cpc925_mc_pdata *pdata = mci->pvt_info;
 866         int bw;
 867         u32 mscr;
 868         u8 si;
 869
 870         mscr = __raw_readl(pdata->vbase + REG_MSCR_OFFSET);
 871         si = (mscr & MSCR_SI_MASK) >> MSCR_SI_SHIFT;
 872
 873         edac_dbg(0, "Mem Scrub Ctrl Register 0x%x\n", mscr);
 874
 875         if (((mscr & MSCR_SCRUB_MOD_MASK) != MSCR_BACKGR_SCRUB) ||
 876             (si == 0)) {
 877                 cpc925_mc_printk(mci, KERN_INFO, "Scrub mode not enabled\n");
 878                 bw = 0;
 879         } else
 880                 bw = CPC925_SCRUB_BLOCK_SIZE * 0xFA67 / si;
 881
 882         return bw;
 883 }
 884
 885 /* Return 0 for single channel; 1 for dual channel */
 886 static int cpc925_mc_get_channels(void __iomem *vbase)
 887 {
 888         int dual = 0;
 889         u32 mbcr;
 890
 891         mbcr = __raw_readl(vbase + REG_MBCR_OFFSET);
 892
 893         /*
 894          * Dual channel only when 128-bit wide physical bus
 895          * and 128-bit configuration.
 896          */
 897         if (((mbcr & MBCR_64BITCFG_MASK) == 0) &&
 898             ((mbcr & MBCR_64BITBUS_MASK) == 0))
 899                 dual = 1;
 900
 901         edac_dbg(0, "%s channel\n", (dual > 0) ? "Dual" : "Single");
 902
 903         return dual;
 904 }
 905
 906 static int cpc925_probe(struct platform_device *pdev)
 907 {
 908         static int edac_mc_idx;
 909         struct mem_ctl_info *mci;
 910         struct edac_mc_layer layers[2];
 911         void __iomem *vbase;
 912         struct cpc925_mc_pdata *pdata;
 913         struct resource *r;
 914         int res = 0, nr_channels;
 915
 916         edac_dbg(0, "%s platform device found!\n", pdev->name);
 917
 918         if (!devres_open_group(&pdev->dev, cpc925_probe, GFP_KERNEL)) {
 919                 res = -ENOMEM;
 920                 goto out;
 921         }
 922
 923         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 924         if (!r) {
 925                 cpc925_printk(KERN_ERR, "Unable to get resource\n");
 926                 res = -ENOENT;
 927                 goto err1;
 928         }
 929
 930         if (!devm_request_mem_region(&pdev->dev,
 931                                      r->start,
 932                                      resource_size(r),
 933                                      pdev->name)) {
 934                 cpc925_printk(KERN_ERR, "Unable to request mem region\n");
 935                 res = -EBUSY;
 936                 goto err1;
 937         }
 938
 939         vbase = devm_ioremap(&pdev->dev, r->start, resource_size(r));
 940         if (!vbase) {
 941                 cpc925_printk(KERN_ERR, "Unable to ioremap device\n");
 942                 res = -ENOMEM;
 943                 goto err2;
 944         }
 945
 946         nr_channels = cpc925_mc_get_channels(vbase) + 1;
 947
 948         layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
 949         layers[0].size = CPC925_NR_CSROWS;
 950         layers[0].is_virt_csrow = true;
 951         layers[1].type = EDAC_MC_LAYER_CHANNEL;
 952         layers[1].size = nr_channels;
 953         layers[1].is_virt_csrow = false;
 954         mci = edac_mc_alloc(edac_mc_idx, ARRAY_SIZE(layers), layers,
 955                             sizeof(struct cpc925_mc_pdata));
 956         if (!mci) {
 957                 cpc925_printk(KERN_ERR, "No memory for mem_ctl_info\n");
 958                 res = -ENOMEM;
 959                 goto err2;
 960         }
 961
 962         pdata = mci->pvt_info;
 963         pdata->vbase = vbase;
 964         pdata->edac_idx = edac_mc_idx++;
 965         pdata->name = pdev->name;
 966
 967         mci->pdev = &pdev->dev;
 968         platform_set_drvdata(pdev, mci);
 969         mci->dev_name = dev_name(&pdev->dev);
 970         mci->mtype_cap = MEM_FLAG_RDDR | MEM_FLAG_DDR;
 971         mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_SECDED;
 972         mci->edac_cap = EDAC_FLAG_SECDED;
 973         mci->mod_name = CPC925_EDAC_MOD_STR;
 974         mci->ctl_name = pdev->name;
 975
 976         if (edac_op_state == EDAC_OPSTATE_POLL)
 977                 mci->edac_check = cpc925_mc_check;
 978
 979         mci->ctl_page_to_phys = NULL;
 980         mci->scrub_mode = SCRUB_SW_SRC;
 981         mci->set_sdram_scrub_rate = NULL;
 982         mci->get_sdram_scrub_rate = cpc925_get_sdram_scrub_rate;
 983
 984         cpc925_init_csrows(mci);
 985
 986         /* Setup memory controller registers */
 987         cpc925_mc_init(mci);
 988
 989         if (edac_mc_add_mc(mci) > 0) {
 990                 cpc925_mc_printk(mci, KERN_ERR, "Failed edac_mc_add_mc()\n");
 991                 goto err3;
 992         }
 993
 994         cpc925_add_edac_devices(vbase);
 995
 996         /* get this far and it's successful */
 997         edac_dbg(0, "success\n");
 998
 999         res = 0;
1000         goto out;
1001
1002 err3:
1003         cpc925_mc_exit(mci);
1004         edac_mc_free(mci);
1005 err2:
1006         devm_release_mem_region(&pdev->dev, r->start, resource_size(r));
1007 err1:
1008         devres_release_group(&pdev->dev, cpc925_probe);
1009 out:
1010         return res;
1011 }
1012
1013 static int cpc925_remove(struct platform_device *pdev)
1014 {
1015         struct mem_ctl_info *mci = platform_get_drvdata(pdev);
1016
1017         /*
1018          * Delete common edac devices before edac mc, because
1019          * the former share the MMIO of the latter.
1020          */
1021         cpc925_del_edac_devices();
1022         cpc925_mc_exit(mci);
1023
1024         edac_mc_del_mc(&pdev->dev);
1025         edac_mc_free(mci);
1026
1027         return 0;
1028 }
1029
1030 static struct platform_driver cpc925_edac_driver = {
1031         .probe = cpc925_probe,
1032         .remove = cpc925_remove,
1033         .driver = {
1034                    .name = "cpc925_edac",
1035         }
1036 };
1037
1038 static int __init cpc925_edac_init(void)
1039 {
1040         int ret = 0;
1041
1042         printk(KERN_INFO "IBM CPC925 EDAC driver " CPC925_EDAC_REVISION "\n");
1043         printk(KERN_INFO "\t(c) 2008 Wind River Systems, Inc\n");
1044
1045         /* Only support POLL mode so far */
1046         edac_op_state = EDAC_OPSTATE_POLL;
1047
1048         ret = platform_driver_register(&cpc925_edac_driver);
1049         if (ret) {
1050                 printk(KERN_WARNING "Failed to register %s\n",
1051                         CPC925_EDAC_MOD_STR);
1052         }
1053
1054         return ret;
1055 }
1056
1057 static void __exit cpc925_edac_exit(void)
1058 {
1059         platform_driver_unregister(&cpc925_edac_driver);
1060 }
1061
1062 module_init(cpc925_edac_init);
1063 module_exit(cpc925_edac_exit);
1064
1065 MODULE_LICENSE("GPL");
1066 MODULE_AUTHOR("Cao Qingtao <qingtao.cao@windriver.com>");
1067 MODULE_DESCRIPTION("IBM CPC925 Bridge and MC EDAC kernel module");