arch/sparc64/kernel/chmc.c

   1 /* $Id: chmc.c,v 1.4 2002/01/08 16:00:14 davem Exp $
   2  * memctrlr.c: Driver for UltraSPARC-III memory controller.
   3  *
   4  * Copyright (C) 2001 David S. Miller (davem@redhat.com)
   5  */
   6
   7 #include <linux/module.h>
   8 #include <linux/kernel.h>
   9 #include <linux/types.h>
  10 #include <linux/slab.h>
  11 #include <linux/list.h>
  12 #include <linux/string.h>
  13 #include <linux/sched.h>
  14 #include <linux/smp.h>
  15 #include <linux/errno.h>
  16 #include <linux/init.h>
  17 #include <asm/spitfire.h>
  18 #include <asm/chmctrl.h>
  19 #include <asm/oplib.h>
  20 #include <asm/io.h>
  21
  22 #define CHMCTRL_NDGRPS  2
  23 #define CHMCTRL_NDIMMS  4
  24
  25 #define DIMMS_PER_MC    (CHMCTRL_NDGRPS * CHMCTRL_NDIMMS)
  26
  27 /* OBP memory-layout property format. */
  28 struct obp_map {
  29         unsigned char   dimm_map[144];
  30         unsigned char   pin_map[576];
  31 };
  32
  33 #define DIMM_LABEL_SZ   8
  34
  35 struct obp_mem_layout {
  36         /* One max 8-byte string label per DIMM.  Usually
  37          * this matches the label on the motherboard where
  38          * that DIMM resides.
  39          */
  40         char            dimm_labels[DIMMS_PER_MC][DIMM_LABEL_SZ];
  41
  42         /* If symmetric use map[0], else it is
  43          * asymmetric and map[1] should be used.
  44          */
  45         char            symmetric;
  46
  47         struct obp_map  map[2];
  48 };
  49
  50 #define CHMCTRL_NBANKS  4
  51
  52 struct bank_info {
  53         struct mctrl_info       *mp;
  54         int                     bank_id;
  55
  56         u64                     raw_reg;
  57         int                     valid;
  58         int                     uk;
  59         int                     um;
  60         int                     lk;
  61         int                     lm;
  62         int                     interleave;
  63         unsigned long           base;
  64         unsigned long           size;
  65 };
  66
  67 struct mctrl_info {
  68         struct list_head        list;
  69         int                     portid;
  70         int                     index;
  71
  72         struct obp_mem_layout   layout_prop;
  73         int                     layout_size;
  74
  75         void __iomem            *regs;
  76
  77         u64                     timing_control1;
  78         u64                     timing_control2;
  79         u64                     timing_control3;
  80         u64                     timing_control4;
  81         u64                     memaddr_control;
  82
  83         struct bank_info        logical_banks[CHMCTRL_NBANKS];
  84 };
  85
  86 static LIST_HEAD(mctrl_list);
  87
  88 /* Does BANK decode PHYS_ADDR? */
  89 static int bank_match(struct bank_info *bp, unsigned long phys_addr)
  90 {
  91         unsigned long upper_bits = (phys_addr & PA_UPPER_BITS) >> PA_UPPER_BITS_SHIFT;
  92         unsigned long lower_bits = (phys_addr & PA_LOWER_BITS) >> PA_LOWER_BITS_SHIFT;
  93
  94         /* Bank must be enabled to match. */
  95         if (bp->valid == 0)
  96                 return 0;
  97
  98         /* Would BANK match upper bits? */
  99         upper_bits ^= bp->um;           /* What bits are different? */
 100         upper_bits  = ~upper_bits;      /* Invert. */
 101         upper_bits |= bp->uk;           /* What bits don't matter for matching? */
 102         upper_bits  = ~upper_bits;      /* Invert. */
 103
 104         if (upper_bits)
 105                 return 0;
 106
 107         /* Would BANK match lower bits? */
 108         lower_bits ^= bp->lm;           /* What bits are different? */
 109         lower_bits  = ~lower_bits;      /* Invert. */
 110         lower_bits |= bp->lk;           /* What bits don't matter for matching? */
 111         lower_bits  = ~lower_bits;      /* Invert. */
 112
 113         if (lower_bits)
 114                 return 0;
 115
 116         /* I always knew you'd be the one. */
 117         return 1;
 118 }
 119
 120 /* Given PHYS_ADDR, search memory controller banks for a match. */
 121 static struct bank_info *find_bank(unsigned long phys_addr)
 122 {
 123         struct list_head *mctrl_head = &mctrl_list;
 124         struct list_head *mctrl_entry = mctrl_head->next;
 125
 126         for (;;) {
 127                 struct mctrl_info *mp =
 128                         list_entry(mctrl_entry, struct mctrl_info, list);
 129                 int bank_no;
 130
 131                 if (mctrl_entry == mctrl_head)
 132                         break;
 133                 mctrl_entry = mctrl_entry->next;
 134
 135                 for (bank_no = 0; bank_no < CHMCTRL_NBANKS; bank_no++) {
 136                         struct bank_info *bp;
 137
 138                         bp = &mp->logical_banks[bank_no];
 139                         if (bank_match(bp, phys_addr))
 140                                 return bp;
 141                 }
 142         }
 143
 144         return NULL;
 145 }
 146
 147 /* This is the main purpose of this driver. */
 148 #define SYNDROME_MIN    -1
 149 #define SYNDROME_MAX    144
 150 int chmc_getunumber(int syndrome_code,
 151                     unsigned long phys_addr,
 152                     char *buf, int buflen)
 153 {
 154         struct bank_info *bp;
 155         struct obp_mem_layout *prop;
 156         int bank_in_controller, first_dimm;
 157
 158         bp = find_bank(phys_addr);
 159         if (bp == NULL ||
 160             syndrome_code < SYNDROME_MIN ||
 161             syndrome_code > SYNDROME_MAX) {
 162                 buf[0] = '?';
 163                 buf[1] = '?';
 164                 buf[2] = '?';
 165                 buf[3] = '\0';
 166                 return 0;
 167         }
 168
 169         prop = &bp->mp->layout_prop;
 170         bank_in_controller = bp->bank_id & (CHMCTRL_NBANKS - 1);
 171         first_dimm  = (bank_in_controller & (CHMCTRL_NDGRPS - 1));
 172         first_dimm *= CHMCTRL_NDIMMS;
 173
 174         if (syndrome_code != SYNDROME_MIN) {
 175                 struct obp_map *map;
 176                 int qword, where_in_line, where, map_index, map_offset;
 177                 unsigned int map_val;
 178
 179                 /* Yaay, single bit error so we can figure out
 180                  * the exact dimm.
 181                  */
 182                 if (prop->symmetric)
 183                         map = &prop->map[0];
 184                 else
 185                         map = &prop->map[1];
 186
 187                 /* Covert syndrome code into the way the bits are
 188                  * positioned on the bus.
 189                  */
 190                 if (syndrome_code < 144 - 16)
 191                         syndrome_code += 16;
 192                 else if (syndrome_code < 144)
 193                         syndrome_code -= (144 - 7);
 194                 else if (syndrome_code < (144 + 3))
 195                         syndrome_code -= (144 + 3 - 4);
 196                 else
 197                         syndrome_code -= 144 + 3;
 198
 199                 /* All this magic has to do with how a cache line
 200                  * comes over the wire on Safari.  A 64-bit line
 201                  * comes over in 4 quadword cycles, each of which
 202                  * transmit ECC/MTAG info as well as the actual
 203                  * data.  144 bits per quadword, 576 total.
 204                  */
 205 #define LINE_SIZE       64
 206 #define LINE_ADDR_MSK   (LINE_SIZE - 1)
 207 #define QW_PER_LINE     4
 208 #define QW_BYTES        (LINE_SIZE / QW_PER_LINE)
 209 #define QW_BITS         144
 210 #define LAST_BIT        (576 - 1)
 211
 212                 qword = (phys_addr & LINE_ADDR_MSK) / QW_BYTES;
 213                 where_in_line = ((3 - qword) * QW_BITS) + syndrome_code;
 214                 where = (LAST_BIT - where_in_line);
 215                 map_index = where >> 2;
 216                 map_offset = where & 0x3;
 217                 map_val = map->dimm_map[map_index];
 218                 map_val = ((map_val >> ((3 - map_offset) << 1)) & (2 - 1));
 219
 220                 sprintf(buf, "%s, pin %3d",
 221                         prop->dimm_labels[first_dimm + map_val],
 222                         map->pin_map[where_in_line]);
 223         } else {
 224                 int dimm;
 225
 226                 /* Multi-bit error, we just dump out all the
 227                  * dimm labels associated with this bank.
 228                  */
 229                 for (dimm = 0; dimm < CHMCTRL_NDIMMS; dimm++) {
 230                         sprintf(buf, "%s ",
 231                                 prop->dimm_labels[first_dimm + dimm]);
 232                         buf += strlen(buf);
 233                 }
 234         }
 235         return 0;
 236 }
 237
 238 /* Accessing the registers is slightly complicated.  If you want
 239  * to get at the memory controller which is on the same processor
 240  * the code is executing, you must use special ASI load/store else
 241  * you go through the global mapping.
 242  */
 243 static u64 read_mcreg(struct mctrl_info *mp, unsigned long offset)
 244 {
 245         unsigned long ret;
 246         int this_cpu = get_cpu();
 247
 248         if (mp->portid == this_cpu) {
 249                 __asm__ __volatile__("ldxa      [%1] %2, %0"
 250                                      : "=r" (ret)
 251                                      : "r" (offset), "i" (ASI_MCU_CTRL_REG));
 252         } else {
 253                 __asm__ __volatile__("ldxa      [%1] %2, %0"
 254                                      : "=r" (ret)
 255                                      : "r" (mp->regs + offset),
 256                                        "i" (ASI_PHYS_BYPASS_EC_E));
 257         }
 258         put_cpu();
 259
 260         return ret;
 261 }
 262
 263 #if 0 /* currently unused */
 264 static void write_mcreg(struct mctrl_info *mp, unsigned long offset, u64 val)
 265 {
 266         if (mp->portid == smp_processor_id()) {
 267                 __asm__ __volatile__("stxa      %0, [%1] %2"
 268                                      : : "r" (val),
 269                                          "r" (offset), "i" (ASI_MCU_CTRL_REG));
 270         } else {
 271                 __asm__ __volatile__("ldxa      %0, [%1] %2"
 272                                      : : "r" (val),
 273                                          "r" (mp->regs + offset),
 274                                          "i" (ASI_PHYS_BYPASS_EC_E));
 275         }
 276 }
 277 #endif
 278
 279 static void interpret_one_decode_reg(struct mctrl_info *mp, int which_bank, u64 val)
 280 {
 281         struct bank_info *p = &mp->logical_banks[which_bank];
 282
 283         p->mp = mp;
 284         p->bank_id = (CHMCTRL_NBANKS * mp->portid) + which_bank;
 285         p->raw_reg = val;
 286         p->valid = (val & MEM_DECODE_VALID) >> MEM_DECODE_VALID_SHIFT;
 287         p->uk = (val & MEM_DECODE_UK) >> MEM_DECODE_UK_SHIFT;
 288         p->um = (val & MEM_DECODE_UM) >> MEM_DECODE_UM_SHIFT;
 289         p->lk = (val & MEM_DECODE_LK) >> MEM_DECODE_LK_SHIFT;
 290         p->lm = (val & MEM_DECODE_LM) >> MEM_DECODE_LM_SHIFT;
 291
 292         p->base  =  (p->um);
 293         p->base &= ~(p->uk);
 294         p->base <<= PA_UPPER_BITS_SHIFT;
 295
 296         switch(p->lk) {
 297         case 0xf:
 298         default:
 299                 p->interleave = 1;
 300                 break;
 301
 302         case 0xe:
 303                 p->interleave = 2;
 304                 break;
 305
 306         case 0xc:
 307                 p->interleave = 4;
 308                 break;
 309
 310         case 0x8:
 311                 p->interleave = 8;
 312                 break;
 313
 314         case 0x0:
 315                 p->interleave = 16;
 316                 break;
 317         };
 318
 319         /* UK[10] is reserved, and UK[11] is not set for the SDRAM
 320          * bank size definition.
 321          */
 322         p->size = (((unsigned long)p->uk &
 323                     ((1UL << 10UL) - 1UL)) + 1UL) << PA_UPPER_BITS_SHIFT;
 324         p->size /= p->interleave;
 325 }
 326
 327 static void fetch_decode_regs(struct mctrl_info *mp)
 328 {
 329         if (mp->layout_size == 0)
 330                 return;
 331
 332         interpret_one_decode_reg(mp, 0,
 333                                  read_mcreg(mp, CHMCTRL_DECODE1));
 334         interpret_one_decode_reg(mp, 1,
 335                                  read_mcreg(mp, CHMCTRL_DECODE2));
 336         interpret_one_decode_reg(mp, 2,
 337                                  read_mcreg(mp, CHMCTRL_DECODE3));
 338         interpret_one_decode_reg(mp, 3,
 339                                  read_mcreg(mp, CHMCTRL_DECODE4));
 340 }
 341
 342 static int init_one_mctrl(int node, int index)
 343 {
 344         struct mctrl_info *mp = kmalloc(sizeof(*mp), GFP_KERNEL);
 345         int portid = prom_getintdefault(node, "portid", -1);
 346         struct linux_prom64_registers p_reg_prop;
 347         int t;
 348
 349         if (!mp)
 350                 return -1;
 351         memset(mp, 0, sizeof(*mp));
 352         if (portid == -1)
 353                 goto fail;
 354
 355         mp->portid = portid;
 356         mp->layout_size = prom_getproplen(node, "memory-layout");
 357         if (mp->layout_size < 0)
 358                 mp->layout_size = 0;
 359         if (mp->layout_size > sizeof(mp->layout_prop))
 360                 goto fail;
 361
 362         if (mp->layout_size > 0)
 363                 prom_getproperty(node, "memory-layout",
 364                                  (char *) &mp->layout_prop,
 365                                  mp->layout_size);
 366
 367         t = prom_getproperty(node, "reg",
 368                              (char *) &p_reg_prop,
 369                              sizeof(p_reg_prop));
 370         if (t < 0 || p_reg_prop.reg_size != 0x48)
 371                 goto fail;
 372
 373         mp->regs = ioremap(p_reg_prop.phys_addr, p_reg_prop.reg_size);
 374         if (mp->regs == NULL)
 375                 goto fail;
 376
 377         if (mp->layout_size != 0UL) {
 378                 mp->timing_control1 = read_mcreg(mp, CHMCTRL_TCTRL1);
 379                 mp->timing_control2 = read_mcreg(mp, CHMCTRL_TCTRL2);
 380                 mp->timing_control3 = read_mcreg(mp, CHMCTRL_TCTRL3);
 381                 mp->timing_control4 = read_mcreg(mp, CHMCTRL_TCTRL4);
 382                 mp->memaddr_control = read_mcreg(mp, CHMCTRL_MACTRL);
 383         }
 384
 385         fetch_decode_regs(mp);
 386
 387         mp->index = index;
 388
 389         list_add(&mp->list, &mctrl_list);
 390
 391         /* Report the device. */
 392         printk(KERN_INFO "chmc%d: US3 memory controller at %p [%s]\n",
 393                mp->index,
 394                mp->regs, (mp->layout_size ? "ACTIVE" : "INACTIVE"));
 395
 396         return 0;
 397
 398 fail:
 399         if (mp) {
 400                 if (mp->regs != NULL)
 401                         iounmap(mp->regs);
 402                 kfree(mp);
 403         }
 404         return -1;
 405 }
 406
 407 static int __init probe_for_string(char *name, int index)
 408 {
 409         int node = prom_getchild(prom_root_node);
 410
 411         while ((node = prom_searchsiblings(node, name)) != 0) {
 412                 int ret = init_one_mctrl(node, index);
 413
 414                 if (!ret)
 415                         index++;
 416
 417                 node = prom_getsibling(node);
 418                 if (!node)
 419                         break;
 420         }
 421
 422         return index;
 423 }
 424
 425 static int __init chmc_init(void)
 426 {
 427         int index;
 428
 429         /* This driver is only for cheetah platforms. */
 430         if (tlb_type != cheetah && tlb_type != cheetah_plus)
 431                 return -ENODEV;
 432
 433         index = probe_for_string("memory-controller", 0);
 434         index = probe_for_string("mc-us3", index);
 435
 436         return 0;
 437 }
 438
 439 static void __exit chmc_cleanup(void)
 440 {
 441         struct list_head *head = &mctrl_list;
 442         struct list_head *tmp = head->next;
 443
 444         for (;;) {
 445                 struct mctrl_info *p =
 446                         list_entry(tmp, struct mctrl_info, list);
 447                 if (tmp == head)
 448                         break;
 449                 tmp = tmp->next;
 450
 451                 list_del(&p->list);
 452                 iounmap(p->regs);
 453                 kfree(p);
 454         }
 455 }
 456
 457 module_init(chmc_init);
 458 module_exit(chmc_cleanup);