arch/ppc/syslib/m8260_pci_erratum9.c

   1 /*
   2  * Workaround for device erratum PCI 9.
   3  * See Motorola's "XPC826xA Family Device Errata Reference."
   4  * The erratum applies to all 8260 family Hip4 processors.  It is scheduled
   5  * to be fixed in HiP4 Rev C.  Erratum PCI 9 states that a simultaneous PCI
   6  * inbound write transaction and PCI outbound read transaction can result in a
   7  * bus deadlock.  The suggested workaround is to use the IDMA controller to
   8  * perform all reads from PCI configuration, memory, and I/O space.
   9  *
  10  * Author:  andy_lowe@mvista.com
  11  *
  12  * 2003 (c) MontaVista Software, Inc. This file is licensed under
  13  * the terms of the GNU General Public License version 2. This program
  14  * is licensed "as is" without any warranty of any kind, whether express
  15  * or implied.
  16  */
  17 #include <linux/kernel.h>
  18 #include <linux/module.h>
  19 #include <linux/pci.h>
  20 #include <linux/types.h>
  21 #include <linux/string.h>
  22
  23 #include <asm/io.h>
  24 #include <asm/pci-bridge.h>
  25 #include <asm/machdep.h>
  26 #include <asm/byteorder.h>
  27 #include <asm/mpc8260.h>
  28 #include <asm/immap_cpm2.h>
  29 #include <asm/cpm2.h>
  30
  31 #include "m82xx_pci.h"
  32
  33 #ifdef CONFIG_8260_PCI9
  34 /*#include <asm/mpc8260_pci9.h>*/ /* included in asm/io.h */
  35
  36 #define IDMA_XFER_BUF_SIZE 64   /* size of the IDMA transfer buffer */
  37
  38 /* define a structure for the IDMA dpram usage */
  39 typedef struct idma_dpram_s {
  40         idma_t pram;                            /* IDMA parameter RAM */
  41         u_char xfer_buf[IDMA_XFER_BUF_SIZE];    /* IDMA transfer buffer */
  42         idma_bd_t bd;                           /* buffer descriptor */
  43 } idma_dpram_t;
  44
  45 /* define offsets relative to start of IDMA dpram */
  46 #define IDMA_XFER_BUF_OFFSET (sizeof(idma_t))
  47 #define IDMA_BD_OFFSET (sizeof(idma_t) + IDMA_XFER_BUF_SIZE)
  48
  49 /* define globals */
  50 static volatile idma_dpram_t *idma_dpram;
  51
  52 /* Exactly one of CONFIG_8260_PCI9_IDMAn must be defined,
  53  * where n is 1, 2, 3, or 4.  This selects the IDMA channel used for
  54  * the PCI9 workaround.
  55  */
  56 #ifdef CONFIG_8260_PCI9_IDMA1
  57 #define IDMA_CHAN 0
  58 #define PROFF_IDMA PROFF_IDMA1_BASE
  59 #define IDMA_PAGE CPM_CR_IDMA1_PAGE
  60 #define IDMA_SBLOCK CPM_CR_IDMA1_SBLOCK
  61 #endif
  62 #ifdef CONFIG_8260_PCI9_IDMA2
  63 #define IDMA_CHAN 1
  64 #define PROFF_IDMA PROFF_IDMA2_BASE
  65 #define IDMA_PAGE CPM_CR_IDMA2_PAGE
  66 #define IDMA_SBLOCK CPM_CR_IDMA2_SBLOCK
  67 #endif
  68 #ifdef CONFIG_8260_PCI9_IDMA3
  69 #define IDMA_CHAN 2
  70 #define PROFF_IDMA PROFF_IDMA3_BASE
  71 #define IDMA_PAGE CPM_CR_IDMA3_PAGE
  72 #define IDMA_SBLOCK CPM_CR_IDMA3_SBLOCK
  73 #endif
  74 #ifdef CONFIG_8260_PCI9_IDMA4
  75 #define IDMA_CHAN 3
  76 #define PROFF_IDMA PROFF_IDMA4_BASE
  77 #define IDMA_PAGE CPM_CR_IDMA4_PAGE
  78 #define IDMA_SBLOCK CPM_CR_IDMA4_SBLOCK
  79 #endif
  80
  81 void idma_pci9_init(void)
  82 {
  83         uint dpram_offset;
  84         volatile idma_t *pram;
  85         volatile im_idma_t *idma_reg;
  86         volatile cpm2_map_t *immap = cpm2_immr;
  87
  88         /* allocate IDMA dpram */
  89         dpram_offset = cpm_dpalloc(sizeof(idma_dpram_t), 64);
  90         idma_dpram = cpm_dpram_addr(dpram_offset);
  91
  92         /* initialize the IDMA parameter RAM */
  93         memset((void *)idma_dpram, 0, sizeof(idma_dpram_t));
  94         pram = &idma_dpram->pram;
  95         pram->ibase = dpram_offset + IDMA_BD_OFFSET;
  96         pram->dpr_buf = dpram_offset + IDMA_XFER_BUF_OFFSET;
  97         pram->ss_max = 32;
  98         pram->dts = 32;
  99
 100         /* initialize the IDMA_BASE pointer to the IDMA parameter RAM */
 101         *((ushort *) &immap->im_dprambase[PROFF_IDMA]) = dpram_offset;
 102
 103         /* initialize the IDMA registers */
 104         idma_reg = (volatile im_idma_t *) &immap->im_sdma.sdma_idsr1;
 105         idma_reg[IDMA_CHAN].idmr = 0;           /* mask all IDMA interrupts */
 106         idma_reg[IDMA_CHAN].idsr = 0xff;        /* clear all event flags */
 107
 108         printk(KERN_WARNING
 109                 "Using IDMA%d for MPC8260 device erratum PCI 9 workaround\n",
 110                 IDMA_CHAN + 1);
 111
 112         return;
 113 }
 114
 115 /* Use the IDMA controller to transfer data from I/O memory to local RAM.
 116  * The src address must be a physical address suitable for use by the DMA
 117  * controller with no translation.  The dst address must be a kernel virtual
 118  * address.  The dst address is translated to a physical address via
 119  * virt_to_phys().
 120  * The sinc argument specifies whether or not the source address is incremented
 121  * by the DMA controller.  The source address is incremented if and only if sinc
 122  * is non-zero.  The destination address is always incremented since the
 123  * destination is always host RAM.
 124  */
 125 static void
 126 idma_pci9_read(u8 *dst, u8 *src, int bytes, int unit_size, int sinc)
 127 {
 128         unsigned long flags;
 129         volatile idma_t *pram = &idma_dpram->pram;
 130         volatile idma_bd_t *bd = &idma_dpram->bd;
 131         volatile cpm2_map_t *immap = cpm2_immr;
 132
 133         local_irq_save(flags);
 134
 135         /* initialize IDMA parameter RAM for this transfer */
 136         if (sinc)
 137                 pram->dcm = IDMA_DCM_DMA_WRAP_64 | IDMA_DCM_SINC
 138                           | IDMA_DCM_DINC | IDMA_DCM_SD_MEM2MEM;
 139         else
 140                 pram->dcm = IDMA_DCM_DMA_WRAP_64 | IDMA_DCM_DINC
 141                           | IDMA_DCM_SD_MEM2MEM;
 142         pram->ibdptr = pram->ibase;
 143         pram->sts = unit_size;
 144         pram->istate = 0;
 145
 146         /* initialize the buffer descriptor */
 147         bd->dst = virt_to_phys(dst);
 148         bd->src = (uint) src;
 149         bd->len = bytes;
 150         bd->flags = IDMA_BD_V | IDMA_BD_W | IDMA_BD_I | IDMA_BD_L | IDMA_BD_DGBL
 151                   | IDMA_BD_DBO_BE | IDMA_BD_SBO_BE | IDMA_BD_SDTB;
 152
 153         /* issue the START_IDMA command to the CP */
 154         while (immap->im_cpm.cp_cpcr & CPM_CR_FLG);
 155         immap->im_cpm.cp_cpcr = mk_cr_cmd(IDMA_PAGE, IDMA_SBLOCK, 0,
 156                                          CPM_CR_START_IDMA) | CPM_CR_FLG;
 157         while (immap->im_cpm.cp_cpcr & CPM_CR_FLG);
 158
 159         /* wait for transfer to complete */
 160         while(bd->flags & IDMA_BD_V);
 161
 162         local_irq_restore(flags);
 163
 164         return;
 165 }
 166
 167 /* Use the IDMA controller to transfer data from I/O memory to local RAM.
 168  * The dst address must be a physical address suitable for use by the DMA
 169  * controller with no translation.  The src address must be a kernel virtual
 170  * address.  The src address is translated to a physical address via
 171  * virt_to_phys().
 172  * The dinc argument specifies whether or not the dest address is incremented
 173  * by the DMA controller.  The source address is incremented if and only if sinc
 174  * is non-zero.  The source address is always incremented since the
 175  * source is always host RAM.
 176  */
 177 static void
 178 idma_pci9_write(u8 *dst, u8 *src, int bytes, int unit_size, int dinc)
 179 {
 180         unsigned long flags;
 181         volatile idma_t *pram = &idma_dpram->pram;
 182         volatile idma_bd_t *bd = &idma_dpram->bd;
 183         volatile cpm2_map_t *immap = cpm2_immr;
 184
 185         local_irq_save(flags);
 186
 187         /* initialize IDMA parameter RAM for this transfer */
 188         if (dinc)
 189                 pram->dcm = IDMA_DCM_DMA_WRAP_64 | IDMA_DCM_SINC
 190                           | IDMA_DCM_DINC | IDMA_DCM_SD_MEM2MEM;
 191         else
 192                 pram->dcm = IDMA_DCM_DMA_WRAP_64 | IDMA_DCM_SINC
 193                           | IDMA_DCM_SD_MEM2MEM;
 194         pram->ibdptr = pram->ibase;
 195         pram->sts = unit_size;
 196         pram->istate = 0;
 197
 198         /* initialize the buffer descriptor */
 199         bd->dst = (uint) dst;
 200         bd->src = virt_to_phys(src);
 201         bd->len = bytes;
 202         bd->flags = IDMA_BD_V | IDMA_BD_W | IDMA_BD_I | IDMA_BD_L | IDMA_BD_DGBL
 203                   | IDMA_BD_DBO_BE | IDMA_BD_SBO_BE | IDMA_BD_SDTB;
 204
 205         /* issue the START_IDMA command to the CP */
 206         while (immap->im_cpm.cp_cpcr & CPM_CR_FLG);
 207         immap->im_cpm.cp_cpcr = mk_cr_cmd(IDMA_PAGE, IDMA_SBLOCK, 0,
 208                                          CPM_CR_START_IDMA) | CPM_CR_FLG;
 209         while (immap->im_cpm.cp_cpcr & CPM_CR_FLG);
 210
 211         /* wait for transfer to complete */
 212         while(bd->flags & IDMA_BD_V);
 213
 214         local_irq_restore(flags);
 215
 216         return;
 217 }
 218
 219 /* Same as idma_pci9_read, but 16-bit little-endian byte swapping is performed
 220  * if the unit_size is 2, and 32-bit little-endian byte swapping is performed if
 221  * the unit_size is 4.
 222  */
 223 static void
 224 idma_pci9_read_le(u8 *dst, u8 *src, int bytes, int unit_size, int sinc)
 225 {
 226         int i;
 227         u8 *p;
 228
 229         idma_pci9_read(dst, src, bytes, unit_size, sinc);
 230         switch(unit_size) {
 231                 case 2:
 232                         for (i = 0, p = dst; i < bytes; i += 2, p += 2)
 233                                 swab16s((u16 *) p);
 234                         break;
 235                 case 4:
 236                         for (i = 0, p = dst; i < bytes; i += 4, p += 4)
 237                                 swab32s((u32 *) p);
 238                         break;
 239                 default:
 240                         break;
 241         }
 242 }
 243 EXPORT_SYMBOL(idma_pci9_init);
 244 EXPORT_SYMBOL(idma_pci9_read);
 245 EXPORT_SYMBOL(idma_pci9_read_le);
 246
 247 static inline int is_pci_mem(unsigned long addr)
 248 {
 249         if (addr >= M82xx_PCI_LOWER_MMIO &&
 250                 addr <= M82xx_PCI_UPPER_MMIO)
 251                 return 1;
 252         if (addr >= M82xx_PCI_LOWER_MEM &&
 253                 addr <= M82xx_PCI_UPPER_MEM)
 254                 return 1;
 255         return 0;
 256 }
 257
 258 #define is_pci_mem(pa) ( (pa > 0x80000000) && (pa < 0xc0000000))
 259 int readb(volatile unsigned char *addr)
 260 {
 261         u8 val;
 262         unsigned long pa = iopa((unsigned long) addr);
 263
 264         if (!is_pci_mem(pa))
 265                 return in_8(addr);
 266
 267         idma_pci9_read((u8 *)&val, (u8 *)pa, sizeof(val), sizeof(val), 0);
 268         return val;
 269 }
 270
 271 int readw(volatile unsigned short *addr)
 272 {
 273         u16 val;
 274         unsigned long pa = iopa((unsigned long) addr);
 275
 276         if (!is_pci_mem(pa))
 277                 return in_le16(addr);
 278
 279         idma_pci9_read((u8 *)&val, (u8 *)pa, sizeof(val), sizeof(val), 0);
 280         return swab16(val);
 281 }
 282
 283 unsigned readl(volatile unsigned *addr)
 284 {
 285         u32 val;
 286         unsigned long pa = iopa((unsigned long) addr);
 287
 288         if (!is_pci_mem(pa))
 289                 return in_le32(addr);
 290
 291         idma_pci9_read((u8 *)&val, (u8 *)pa, sizeof(val), sizeof(val), 0);
 292         return swab32(val);
 293 }
 294
 295 int inb(unsigned port)
 296 {
 297         u8 val;
 298         u8 *addr = (u8 *)(port + _IO_BASE);
 299
 300         idma_pci9_read((u8 *)&val, (u8 *)addr, sizeof(val), sizeof(val), 0);
 301         return val;
 302 }
 303
 304 int inw(unsigned port)
 305 {
 306         u16 val;
 307         u8 *addr = (u8 *)(port + _IO_BASE);
 308
 309         idma_pci9_read((u8 *)&val, (u8 *)addr, sizeof(val), sizeof(val), 0);
 310         return swab16(val);
 311 }
 312
 313 unsigned inl(unsigned port)
 314 {
 315         u32 val;
 316         u8 *addr = (u8 *)(port + _IO_BASE);
 317
 318         idma_pci9_read((u8 *)&val, (u8 *)addr, sizeof(val), sizeof(val), 0);
 319         return swab32(val);
 320 }
 321
 322 void insb(unsigned port, void *buf, int ns)
 323 {
 324         u8 *addr = (u8 *)(port + _IO_BASE);
 325
 326         idma_pci9_read((u8 *)buf, (u8 *)addr, ns*sizeof(u8), sizeof(u8), 0);
 327 }
 328
 329 void insw(unsigned port, void *buf, int ns)
 330 {
 331         u8 *addr = (u8 *)(port + _IO_BASE);
 332
 333         idma_pci9_read((u8 *)buf, (u8 *)addr, ns*sizeof(u16), sizeof(u16), 0);
 334 }
 335
 336 void insl(unsigned port, void *buf, int nl)
 337 {
 338         u8 *addr = (u8 *)(port + _IO_BASE);
 339
 340         idma_pci9_read((u8 *)buf, (u8 *)addr, nl*sizeof(u32), sizeof(u32), 0);
 341 }
 342
 343 void *memcpy_fromio(void *dest, unsigned long src, size_t count)
 344 {
 345         unsigned long pa = iopa((unsigned long) src);
 346
 347         if (is_pci_mem(pa))
 348                 idma_pci9_read((u8 *)dest, (u8 *)pa, count, 32, 1);
 349         else
 350                 memcpy(dest, (void *)src, count);
 351         return dest;
 352 }
 353
 354 EXPORT_SYMBOL(readb);
 355 EXPORT_SYMBOL(readw);
 356 EXPORT_SYMBOL(readl);
 357 EXPORT_SYMBOL(inb);
 358 EXPORT_SYMBOL(inw);
 359 EXPORT_SYMBOL(inl);
 360 EXPORT_SYMBOL(insb);
 361 EXPORT_SYMBOL(insw);
 362 EXPORT_SYMBOL(insl);
 363 EXPORT_SYMBOL(memcpy_fromio);
 364
 365 #endif  /* ifdef CONFIG_8260_PCI9 */
 366
 367 /* Indirect PCI routines adapted from arch/ppc/kernel/indirect_pci.c.
 368  * Copyright (C) 1998 Gabriel Paubert.
 369  */
 370 #ifndef CONFIG_8260_PCI9
 371 #define cfg_read(val, addr, type, op)   *val = op((type)(addr))
 372 #else
 373 #define cfg_read(val, addr, type, op) \
 374         idma_pci9_read_le((u8*)(val),(u8*)(addr),sizeof(*(val)),sizeof(*(val)),0)
 375 #endif
 376
 377 #define cfg_write(val, addr, type, op)  op((type *)(addr), (val))
 378
 379 static int indirect_write_config(struct pci_bus *pbus, unsigned int devfn, int where,
 380                          int size, u32 value)
 381 {
 382         struct pci_controller *hose = pbus->sysdata;
 383         u8 cfg_type = 0;
 384         if (ppc_md.pci_exclude_device)
 385                 if (ppc_md.pci_exclude_device(pbus->number, devfn))
 386                         return PCIBIOS_DEVICE_NOT_FOUND;
 387
 388         if (hose->set_cfg_type)
 389                 if (pbus->number != hose->first_busno)
 390                         cfg_type = 1;
 391
 392         out_be32(hose->cfg_addr,
 393                  (((where & 0xfc) | cfg_type) << 24) | (devfn << 16)
 394                  | ((pbus->number - hose->bus_offset) << 8) | 0x80);
 395
 396         switch (size)
 397         {
 398                 case 1:
 399                         cfg_write(value, hose->cfg_data + (where & 3), u8, out_8);
 400                         break;
 401                 case 2:
 402                         cfg_write(value, hose->cfg_data + (where & 2), u16, out_le16);
 403                         break;
 404                 case 4:
 405                         cfg_write(value, hose->cfg_data + (where & 0), u32, out_le32);
 406                         break;
 407         }
 408         return PCIBIOS_SUCCESSFUL;
 409 }
 410
 411 static int indirect_read_config(struct pci_bus *pbus, unsigned int devfn, int where,
 412                          int size, u32 *value)
 413 {
 414         struct pci_controller *hose = pbus->sysdata;
 415         u8 cfg_type = 0;
 416         if (ppc_md.pci_exclude_device)
 417                 if (ppc_md.pci_exclude_device(pbus->number, devfn))
 418                         return PCIBIOS_DEVICE_NOT_FOUND;
 419
 420         if (hose->set_cfg_type)
 421                 if (pbus->number != hose->first_busno)
 422                         cfg_type = 1;
 423
 424         out_be32(hose->cfg_addr,
 425                  (((where & 0xfc) | cfg_type) << 24) | (devfn << 16)
 426                  | ((pbus->number - hose->bus_offset) << 8) | 0x80);
 427
 428         switch (size)
 429         {
 430                 case 1:
 431                         cfg_read(value, hose->cfg_data + (where & 3), u8 *, in_8);
 432                         break;
 433                 case 2:
 434                         cfg_read(value, hose->cfg_data + (where & 2), u16 *, in_le16);
 435                         break;
 436                 case 4:
 437                         cfg_read(value, hose->cfg_data + (where & 0), u32 *, in_le32);
 438                         break;
 439         }
 440         return PCIBIOS_SUCCESSFUL;
 441 }
 442
 443 static struct pci_ops indirect_pci_ops =
 444 {
 445         .read = indirect_read_config,
 446         .write = indirect_write_config,
 447 };
 448
 449 void
 450 setup_m8260_indirect_pci(struct pci_controller* hose, u32 cfg_addr, u32 cfg_data)
 451 {
 452         hose->ops = &indirect_pci_ops;
 453         hose->cfg_addr = (unsigned int *) ioremap(cfg_addr, 4);
 454         hose->cfg_data = (unsigned char *) ioremap(cfg_data, 4);
 455 }