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   1 /*
   2  *  linux/drivers/mmc/imxmmc.c - Motorola i.MX MMCI driver
   3  *
   4  *  Copyright (C) 2004 Sascha Hauer, Pengutronix <sascha@saschahauer.de>
   5  *  Copyright (C) 2006 Pavel Pisa, PiKRON <ppisa@pikron.com>
   6  *
   7  *  derived from pxamci.c by Russell King
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  *
  13  *  2005-04-17 Pavel Pisa <pisa@cmp.felk.cvut.cz>
  14  *             Changed to conform redesigned i.MX scatter gather DMA interface
  15  *
  16  *  2005-11-04 Pavel Pisa <pisa@cmp.felk.cvut.cz>
  17  *             Updated for 2.6.14 kernel
  18  *
  19  *  2005-12-13 Jay Monkman <jtm@smoothsmoothie.com>
  20  *             Found and corrected problems in the write path
  21  *
  22  *  2005-12-30 Pavel Pisa <pisa@cmp.felk.cvut.cz>
  23  *             The event handling rewritten right way in softirq.
  24  *             Added many ugly hacks and delays to overcome SDHC
  25  *             deficiencies
  26  *
  27  */
  28
  29 #ifdef CONFIG_MMC_DEBUG
  30 #define DEBUG
  31 #else
  32 #undef  DEBUG
  33 #endif
  34
  35 #include <linux/module.h>
  36 #include <linux/init.h>
  37 #include <linux/ioport.h>
  38 #include <linux/platform_device.h>
  39 #include <linux/interrupt.h>
  40 #include <linux/blkdev.h>
  41 #include <linux/dma-mapping.h>
  42 #include <linux/mmc/host.h>
  43 #include <linux/mmc/card.h>
  44 #include <linux/mmc/protocol.h>
  45 #include <linux/delay.h>
  46
  47 #include <asm/dma.h>
  48 #include <asm/io.h>
  49 #include <asm/irq.h>
  50 #include <asm/sizes.h>
  51 #include <asm/arch/mmc.h>
  52 #include <asm/arch/imx-dma.h>
  53
  54 #include "imxmmc.h"
  55
  56 #define DRIVER_NAME "imx-mmc"
  57
  58 #define IMXMCI_INT_MASK_DEFAULT (INT_MASK_BUF_READY | INT_MASK_DATA_TRAN | \
  59                       INT_MASK_WRITE_OP_DONE | INT_MASK_END_CMD_RES | \
  60                       INT_MASK_AUTO_CARD_DETECT | INT_MASK_DAT0_EN | INT_MASK_SDIO)
  61
  62 struct imxmci_host {
  63         struct mmc_host         *mmc;
  64         spinlock_t              lock;
  65         struct resource         *res;
  66         int                     irq;
  67         imx_dmach_t             dma;
  68         unsigned int            clkrt;
  69         unsigned int            cmdat;
  70         volatile unsigned int   imask;
  71         unsigned int            power_mode;
  72         unsigned int            present;
  73         struct imxmmc_platform_data *pdata;
  74
  75         struct mmc_request      *req;
  76         struct mmc_command      *cmd;
  77         struct mmc_data         *data;
  78
  79         struct timer_list       timer;
  80         struct tasklet_struct   tasklet;
  81         unsigned int            status_reg;
  82         unsigned long           pending_events;
  83         /* Next to fields are there for CPU driven transfers to overcome SDHC deficiencies */
  84         u16                     *data_ptr;
  85         unsigned int            data_cnt;
  86         atomic_t                stuck_timeout;
  87
  88         unsigned int            dma_nents;
  89         unsigned int            dma_size;
  90         unsigned int            dma_dir;
  91         int                     dma_allocated;
  92
  93         unsigned char           actual_bus_width;
  94 };
  95
  96 #define IMXMCI_PEND_IRQ_b       0
  97 #define IMXMCI_PEND_DMA_END_b   1
  98 #define IMXMCI_PEND_DMA_ERR_b   2
  99 #define IMXMCI_PEND_WAIT_RESP_b 3
 100 #define IMXMCI_PEND_DMA_DATA_b  4
 101 #define IMXMCI_PEND_CPU_DATA_b  5
 102 #define IMXMCI_PEND_CARD_XCHG_b 6
 103 #define IMXMCI_PEND_SET_INIT_b  7
 104 #define IMXMCI_PEND_STARTED_b   8
 105
 106 #define IMXMCI_PEND_IRQ_m       (1 << IMXMCI_PEND_IRQ_b)
 107 #define IMXMCI_PEND_DMA_END_m   (1 << IMXMCI_PEND_DMA_END_b)
 108 #define IMXMCI_PEND_DMA_ERR_m   (1 << IMXMCI_PEND_DMA_ERR_b)
 109 #define IMXMCI_PEND_WAIT_RESP_m (1 << IMXMCI_PEND_WAIT_RESP_b)
 110 #define IMXMCI_PEND_DMA_DATA_m  (1 << IMXMCI_PEND_DMA_DATA_b)
 111 #define IMXMCI_PEND_CPU_DATA_m  (1 << IMXMCI_PEND_CPU_DATA_b)
 112 #define IMXMCI_PEND_CARD_XCHG_m (1 << IMXMCI_PEND_CARD_XCHG_b)
 113 #define IMXMCI_PEND_SET_INIT_m  (1 << IMXMCI_PEND_SET_INIT_b)
 114 #define IMXMCI_PEND_STARTED_m   (1 << IMXMCI_PEND_STARTED_b)
 115
 116 static void imxmci_stop_clock(struct imxmci_host *host)
 117 {
 118         int i = 0;
 119         MMC_STR_STP_CLK &= ~STR_STP_CLK_START_CLK;
 120         while(i < 0x1000) {
 121                 if(!(i & 0x7f))
 122                         MMC_STR_STP_CLK |= STR_STP_CLK_STOP_CLK;
 123
 124                 if(!(MMC_STATUS & STATUS_CARD_BUS_CLK_RUN)) {
 125                         /* Check twice before cut */
 126                         if(!(MMC_STATUS & STATUS_CARD_BUS_CLK_RUN))
 127                                 return;
 128                 }
 129
 130                 i++;
 131         }
 132         dev_dbg(mmc_dev(host->mmc), "imxmci_stop_clock blocked, no luck\n");
 133 }
 134
 135 static int imxmci_start_clock(struct imxmci_host *host)
 136 {
 137         unsigned int trials = 0;
 138         unsigned int delay_limit = 128;
 139         unsigned long flags;
 140
 141         MMC_STR_STP_CLK &= ~STR_STP_CLK_STOP_CLK;
 142
 143         clear_bit(IMXMCI_PEND_STARTED_b, &host->pending_events);
 144
 145         /*
 146          * Command start of the clock, this usually succeeds in less
 147          * then 6 delay loops, but during card detection (low clockrate)
 148          * it takes up to 5000 delay loops and sometimes fails for the first time
 149          */
 150         MMC_STR_STP_CLK |= STR_STP_CLK_START_CLK;
 151
 152         do {
 153                 unsigned int delay = delay_limit;
 154
 155                 while(delay--){
 156                         if(MMC_STATUS & STATUS_CARD_BUS_CLK_RUN)
 157                                 /* Check twice before cut */
 158                                 if(MMC_STATUS & STATUS_CARD_BUS_CLK_RUN)
 159                                         return 0;
 160
 161                         if(test_bit(IMXMCI_PEND_STARTED_b, &host->pending_events))
 162                                 return 0;
 163                 }
 164
 165                 local_irq_save(flags);
 166                 /*
 167                  * Ensure, that request is not doubled under all possible circumstances.
 168                  * It is possible, that cock running state is missed, because some other
 169                  * IRQ or schedule delays this function execution and the clocks has
 170                  * been already stopped by other means (response processing, SDHC HW)
 171                  */
 172                 if(!test_bit(IMXMCI_PEND_STARTED_b, &host->pending_events))
 173                         MMC_STR_STP_CLK |= STR_STP_CLK_START_CLK;
 174                 local_irq_restore(flags);
 175
 176         } while(++trials<256);
 177
 178         dev_err(mmc_dev(host->mmc), "imxmci_start_clock blocked, no luck\n");
 179
 180         return -1;
 181 }
 182
 183 static void imxmci_softreset(void)
 184 {
 185         /* reset sequence */
 186         MMC_STR_STP_CLK = 0x8;
 187         MMC_STR_STP_CLK = 0xD;
 188         MMC_STR_STP_CLK = 0x5;
 189         MMC_STR_STP_CLK = 0x5;
 190         MMC_STR_STP_CLK = 0x5;
 191         MMC_STR_STP_CLK = 0x5;
 192         MMC_STR_STP_CLK = 0x5;
 193         MMC_STR_STP_CLK = 0x5;
 194         MMC_STR_STP_CLK = 0x5;
 195         MMC_STR_STP_CLK = 0x5;
 196
 197         MMC_RES_TO = 0xff;
 198         MMC_BLK_LEN = 512;
 199         MMC_NOB = 1;
 200 }
 201
 202 static int imxmci_busy_wait_for_status(struct imxmci_host *host,
 203                         unsigned int *pstat, unsigned int stat_mask,
 204                         int timeout, const char *where)
 205 {
 206         int loops=0;
 207         while(!(*pstat & stat_mask)) {
 208                 loops+=2;
 209                 if(loops >= timeout) {
 210                         dev_dbg(mmc_dev(host->mmc), "busy wait timeout in %s, STATUS = 0x%x (0x%x)\n",
 211                                 where, *pstat, stat_mask);
 212                         return -1;
 213                 }
 214                 udelay(2);
 215                 *pstat |= MMC_STATUS;
 216         }
 217         if(!loops)
 218                 return 0;
 219
 220         /* The busy-wait is expected there for clock <8MHz due to SDHC hardware flaws */
 221         if(!(stat_mask & STATUS_END_CMD_RESP) || (host->mmc->ios.clock>=8000000))
 222                 dev_info(mmc_dev(host->mmc), "busy wait for %d usec in %s, STATUS = 0x%x (0x%x)\n",
 223                         loops, where, *pstat, stat_mask);
 224         return loops;
 225 }
 226
 227 static void imxmci_setup_data(struct imxmci_host *host, struct mmc_data *data)
 228 {
 229         unsigned int nob = data->blocks;
 230         unsigned int blksz = data->blksz;
 231         unsigned int datasz = nob * blksz;
 232         int i;
 233
 234         if (data->flags & MMC_DATA_STREAM)
 235                 nob = 0xffff;
 236
 237         host->data = data;
 238         data->bytes_xfered = 0;
 239
 240         MMC_NOB = nob;
 241         MMC_BLK_LEN = blksz;
 242
 243         /*
 244          * DMA cannot be used for small block sizes, we have to use CPU driven transfers otherwise.
 245          * We are in big troubles for non-512 byte transfers according to note in the paragraph
 246          * 20.6.7 of User Manual anyway, but we need to be able to transfer SCR at least.
 247          * The situation is even more complex in reality. The SDHC in not able to handle wll
 248          * partial FIFO fills and reads. The length has to be rounded up to burst size multiple.
 249          * This is required for SCR read at least.
 250          */
 251         if (datasz < 64) {
 252                 host->dma_size = datasz;
 253                 if (data->flags & MMC_DATA_READ) {
 254                         host->dma_dir = DMA_FROM_DEVICE;
 255
 256                         /* Hack to enable read SCR */
 257                         if(datasz < 16) {
 258                                 MMC_NOB = 1;
 259                                 MMC_BLK_LEN = 16;
 260                         }
 261                 } else {
 262                         host->dma_dir = DMA_TO_DEVICE;
 263                 }
 264
 265                 /* Convert back to virtual address */
 266                 host->data_ptr = (u16*)(page_address(data->sg->page) + data->sg->offset);
 267                 host->data_cnt = 0;
 268
 269                 clear_bit(IMXMCI_PEND_DMA_DATA_b, &host->pending_events);
 270                 set_bit(IMXMCI_PEND_CPU_DATA_b, &host->pending_events);
 271
 272                 return;
 273         }
 274
 275         if (data->flags & MMC_DATA_READ) {
 276                 host->dma_dir = DMA_FROM_DEVICE;
 277                 host->dma_nents = dma_map_sg(mmc_dev(host->mmc), data->sg,
 278                                                 data->sg_len,  host->dma_dir);
 279
 280                 imx_dma_setup_sg(host->dma, data->sg, data->sg_len, datasz,
 281                         host->res->start + MMC_BUFFER_ACCESS_OFS, DMA_MODE_READ);
 282
 283                 /*imx_dma_setup_mem2dev_ccr(host->dma, DMA_MODE_READ, IMX_DMA_WIDTH_16, CCR_REN);*/
 284                 CCR(host->dma) = CCR_DMOD_LINEAR | CCR_DSIZ_32 | CCR_SMOD_FIFO | CCR_SSIZ_16 | CCR_REN;
 285         } else {
 286                 host->dma_dir = DMA_TO_DEVICE;
 287
 288                 host->dma_nents = dma_map_sg(mmc_dev(host->mmc), data->sg,
 289                                                 data->sg_len,  host->dma_dir);
 290
 291                 imx_dma_setup_sg(host->dma, data->sg, data->sg_len, datasz,
 292                         host->res->start + MMC_BUFFER_ACCESS_OFS, DMA_MODE_WRITE);
 293
 294                 /*imx_dma_setup_mem2dev_ccr(host->dma, DMA_MODE_WRITE, IMX_DMA_WIDTH_16, CCR_REN);*/
 295                 CCR(host->dma) = CCR_SMOD_LINEAR | CCR_SSIZ_32 | CCR_DMOD_FIFO | CCR_DSIZ_16 | CCR_REN;
 296         }
 297
 298 #if 1   /* This code is there only for consistency checking and can be disabled in future */
 299         host->dma_size = 0;
 300         for(i=0; i<host->dma_nents; i++)
 301                 host->dma_size+=data->sg[i].length;
 302
 303         if (datasz > host->dma_size) {
 304                 dev_err(mmc_dev(host->mmc), "imxmci_setup_data datasz 0x%x > 0x%x dm_size\n",
 305                        datasz, host->dma_size);
 306         }
 307 #endif
 308
 309         host->dma_size = datasz;
 310
 311         wmb();
 312
 313         if(host->actual_bus_width == MMC_BUS_WIDTH_4)
 314                 BLR(host->dma) = 0;     /* burst 64 byte read / 64 bytes write */
 315         else
 316                 BLR(host->dma) = 16;    /* burst 16 byte read / 16 bytes write */
 317
 318         RSSR(host->dma) = DMA_REQ_SDHC;
 319
 320         set_bit(IMXMCI_PEND_DMA_DATA_b, &host->pending_events);
 321         clear_bit(IMXMCI_PEND_CPU_DATA_b, &host->pending_events);
 322
 323         /* start DMA engine for read, write is delayed after initial response */
 324         if (host->dma_dir == DMA_FROM_DEVICE) {
 325                 imx_dma_enable(host->dma);
 326         }
 327 }
 328
 329 static void imxmci_start_cmd(struct imxmci_host *host, struct mmc_command *cmd, unsigned int cmdat)
 330 {
 331         unsigned long flags;
 332         u32 imask;
 333
 334         WARN_ON(host->cmd != NULL);
 335         host->cmd = cmd;
 336
 337         /* Ensure, that clock are stopped else command programming and start fails */
 338         imxmci_stop_clock(host);
 339
 340         if (cmd->flags & MMC_RSP_BUSY)
 341                 cmdat |= CMD_DAT_CONT_BUSY;
 342
 343         switch (mmc_resp_type(cmd)) {
 344         case MMC_RSP_R1: /* short CRC, OPCODE */
 345         case MMC_RSP_R1B:/* short CRC, OPCODE, BUSY */
 346                 cmdat |= CMD_DAT_CONT_RESPONSE_FORMAT_R1;
 347                 break;
 348         case MMC_RSP_R2: /* long 136 bit + CRC */
 349                 cmdat |= CMD_DAT_CONT_RESPONSE_FORMAT_R2;
 350                 break;
 351         case MMC_RSP_R3: /* short */
 352                 cmdat |= CMD_DAT_CONT_RESPONSE_FORMAT_R3;
 353                 break;
 354         case MMC_RSP_R6: /* short CRC */
 355                 cmdat |= CMD_DAT_CONT_RESPONSE_FORMAT_R6;
 356                 break;
 357         default:
 358                 break;
 359         }
 360
 361         if ( test_and_clear_bit(IMXMCI_PEND_SET_INIT_b, &host->pending_events) )
 362                 cmdat |= CMD_DAT_CONT_INIT; /* This command needs init */
 363
 364         if ( host->actual_bus_width == MMC_BUS_WIDTH_4 )
 365                 cmdat |= CMD_DAT_CONT_BUS_WIDTH_4;
 366
 367         MMC_CMD = cmd->opcode;
 368         MMC_ARGH = cmd->arg >> 16;
 369         MMC_ARGL = cmd->arg & 0xffff;
 370         MMC_CMD_DAT_CONT = cmdat;
 371
 372         atomic_set(&host->stuck_timeout, 0);
 373         set_bit(IMXMCI_PEND_WAIT_RESP_b, &host->pending_events);
 374
 375
 376         imask = IMXMCI_INT_MASK_DEFAULT;
 377         imask &= ~INT_MASK_END_CMD_RES;
 378         if ( cmdat & CMD_DAT_CONT_DATA_ENABLE ) {
 379                 /*imask &= ~INT_MASK_BUF_READY;*/
 380                 imask &= ~INT_MASK_DATA_TRAN;
 381                 if ( cmdat & CMD_DAT_CONT_WRITE )
 382                         imask &= ~INT_MASK_WRITE_OP_DONE;
 383                 if(test_bit(IMXMCI_PEND_CPU_DATA_b, &host->pending_events))
 384                         imask &= ~INT_MASK_BUF_READY;
 385         }
 386
 387         spin_lock_irqsave(&host->lock, flags);
 388         host->imask = imask;
 389         MMC_INT_MASK = host->imask;
 390         spin_unlock_irqrestore(&host->lock, flags);
 391
 392         dev_dbg(mmc_dev(host->mmc), "CMD%02d (0x%02x) mask set to 0x%04x\n",
 393                 cmd->opcode, cmd->opcode, imask);
 394
 395         imxmci_start_clock(host);
 396 }
 397
 398 static void imxmci_finish_request(struct imxmci_host *host, struct mmc_request *req)
 399 {
 400         unsigned long flags;
 401
 402         spin_lock_irqsave(&host->lock, flags);
 403
 404         host->pending_events &= ~(IMXMCI_PEND_WAIT_RESP_m | IMXMCI_PEND_DMA_END_m |
 405                         IMXMCI_PEND_DMA_DATA_m | IMXMCI_PEND_CPU_DATA_m);
 406
 407         host->imask = IMXMCI_INT_MASK_DEFAULT;
 408         MMC_INT_MASK = host->imask;
 409
 410         spin_unlock_irqrestore(&host->lock, flags);
 411
 412         host->req = NULL;
 413         host->cmd = NULL;
 414         host->data = NULL;
 415         mmc_request_done(host->mmc, req);
 416 }
 417
 418 static int imxmci_finish_data(struct imxmci_host *host, unsigned int stat)
 419 {
 420         struct mmc_data *data = host->data;
 421         int data_error;
 422
 423         if(test_and_clear_bit(IMXMCI_PEND_DMA_DATA_b, &host->pending_events)){
 424                 imx_dma_disable(host->dma);
 425                 dma_unmap_sg(mmc_dev(host->mmc), data->sg, host->dma_nents,
 426                              host->dma_dir);
 427         }
 428
 429         if ( stat & STATUS_ERR_MASK ) {
 430                 dev_dbg(mmc_dev(host->mmc), "request failed. status: 0x%08x\n",stat);
 431                 if(stat & (STATUS_CRC_READ_ERR | STATUS_CRC_WRITE_ERR))
 432                         data->error = MMC_ERR_BADCRC;
 433                 else if(stat & STATUS_TIME_OUT_READ)
 434                         data->error = MMC_ERR_TIMEOUT;
 435                 else
 436                         data->error = MMC_ERR_FAILED;
 437         } else {
 438                 data->bytes_xfered = host->dma_size;
 439         }
 440
 441         data_error = data->error;
 442
 443         host->data = NULL;
 444
 445         return data_error;
 446 }
 447
 448 static int imxmci_cmd_done(struct imxmci_host *host, unsigned int stat)
 449 {
 450         struct mmc_command *cmd = host->cmd;
 451         int i;
 452         u32 a,b,c;
 453         struct mmc_data *data = host->data;
 454
 455         if (!cmd)
 456                 return 0;
 457
 458         host->cmd = NULL;
 459
 460         if (stat & STATUS_TIME_OUT_RESP) {
 461                 dev_dbg(mmc_dev(host->mmc), "CMD TIMEOUT\n");
 462                 cmd->error = MMC_ERR_TIMEOUT;
 463         } else if (stat & STATUS_RESP_CRC_ERR && cmd->flags & MMC_RSP_CRC) {
 464                 dev_dbg(mmc_dev(host->mmc), "cmd crc error\n");
 465                 cmd->error = MMC_ERR_BADCRC;
 466         }
 467
 468         if(cmd->flags & MMC_RSP_PRESENT) {
 469                 if(cmd->flags & MMC_RSP_136) {
 470                         for (i = 0; i < 4; i++) {
 471                                 u32 a = MMC_RES_FIFO & 0xffff;
 472                                 u32 b = MMC_RES_FIFO & 0xffff;
 473                                 cmd->resp[i] = a<<16 | b;
 474                         }
 475                 } else {
 476                         a = MMC_RES_FIFO & 0xffff;
 477                         b = MMC_RES_FIFO & 0xffff;
 478                         c = MMC_RES_FIFO & 0xffff;
 479                         cmd->resp[0] = a<<24 | b<<8 | c>>8;
 480                 }
 481         }
 482
 483         dev_dbg(mmc_dev(host->mmc), "RESP 0x%08x, 0x%08x, 0x%08x, 0x%08x, error %d\n",
 484                 cmd->resp[0], cmd->resp[1], cmd->resp[2], cmd->resp[3], cmd->error);
 485
 486         if (data && (cmd->error == MMC_ERR_NONE) && !(stat & STATUS_ERR_MASK)) {
 487                 if (host->req->data->flags & MMC_DATA_WRITE) {
 488
 489                         /* Wait for FIFO to be empty before starting DMA write */
 490
 491                         stat = MMC_STATUS;
 492                         if(imxmci_busy_wait_for_status(host, &stat,
 493                                 STATUS_APPL_BUFF_FE,
 494                                 40, "imxmci_cmd_done DMA WR") < 0) {
 495                                 cmd->error = MMC_ERR_FIFO;
 496                                 imxmci_finish_data(host, stat);
 497                                 if(host->req)
 498                                         imxmci_finish_request(host, host->req);
 499                                 dev_warn(mmc_dev(host->mmc), "STATUS = 0x%04x\n",
 500                                        stat);
 501                                 return 0;
 502                         }
 503
 504                         if(test_bit(IMXMCI_PEND_DMA_DATA_b, &host->pending_events)) {
 505                                 imx_dma_enable(host->dma);
 506                         }
 507                 }
 508         } else {
 509                 struct mmc_request *req;
 510                 imxmci_stop_clock(host);
 511                 req = host->req;
 512
 513                 if(data)
 514                         imxmci_finish_data(host, stat);
 515
 516                 if( req ) {
 517                         imxmci_finish_request(host, req);
 518                 } else {
 519                         dev_warn(mmc_dev(host->mmc), "imxmci_cmd_done: no request to finish\n");
 520                 }
 521         }
 522
 523         return 1;
 524 }
 525
 526 static int imxmci_data_done(struct imxmci_host *host, unsigned int stat)
 527 {
 528         struct mmc_data *data = host->data;
 529         int data_error;
 530
 531         if (!data)
 532                 return 0;
 533
 534         data_error = imxmci_finish_data(host, stat);
 535
 536         if (host->req->stop) {
 537                 imxmci_stop_clock(host);
 538                 imxmci_start_cmd(host, host->req->stop, 0);
 539         } else {
 540                 struct mmc_request *req;
 541                 req = host->req;
 542                 if( req ) {
 543                         imxmci_finish_request(host, req);
 544                 } else {
 545                         dev_warn(mmc_dev(host->mmc), "imxmci_data_done: no request to finish\n");
 546                 }
 547         }
 548
 549         return 1;
 550 }
 551
 552 static int imxmci_cpu_driven_data(struct imxmci_host *host, unsigned int *pstat)
 553 {
 554         int i;
 555         int burst_len;
 556         int flush_len;
 557         int trans_done = 0;
 558         unsigned int stat = *pstat;
 559
 560         if(host->actual_bus_width != MMC_BUS_WIDTH_4)
 561                 burst_len = 16;
 562         else
 563                 burst_len = 64;
 564
 565         /* This is unfortunately required */
 566         dev_dbg(mmc_dev(host->mmc), "imxmci_cpu_driven_data running STATUS = 0x%x\n",
 567                 stat);
 568
 569         if(host->dma_dir == DMA_FROM_DEVICE) {
 570                 imxmci_busy_wait_for_status(host, &stat,
 571                                 STATUS_APPL_BUFF_FF | STATUS_DATA_TRANS_DONE,
 572                                 20, "imxmci_cpu_driven_data read");
 573
 574                 while((stat & (STATUS_APPL_BUFF_FF |  STATUS_DATA_TRANS_DONE)) &&
 575                       (host->data_cnt < host->dma_size)) {
 576                         if(burst_len >= host->dma_size - host->data_cnt) {
 577                                 flush_len = burst_len;
 578                                 burst_len = host->dma_size - host->data_cnt;
 579                                 flush_len -= burst_len;
 580                                 host->data_cnt = host->dma_size;
 581                                 trans_done = 1;
 582                         } else {
 583                                 flush_len = 0;
 584                                 host->data_cnt += burst_len;
 585                         }
 586
 587                         for(i = burst_len; i>=2 ; i-=2) {
 588                                 *(host->data_ptr++) = MMC_BUFFER_ACCESS;
 589                                 udelay(20);     /* required for clocks < 8MHz*/
 590                         }
 591
 592                         if(i == 1)
 593                                 *(u8*)(host->data_ptr) = MMC_BUFFER_ACCESS;
 594
 595                         stat = MMC_STATUS;
 596
 597                         /* Flush extra bytes from FIFO */
 598                         while(flush_len && !(stat & STATUS_DATA_TRANS_DONE)){
 599                                 i = MMC_BUFFER_ACCESS;
 600                                 stat = MMC_STATUS;
 601                                 stat &= ~STATUS_CRC_READ_ERR; /* Stupid but required there */
 602                         }
 603
 604                         dev_dbg(mmc_dev(host->mmc), "imxmci_cpu_driven_data read burst %d STATUS = 0x%x\n",
 605                                 burst_len, stat);
 606                 }
 607         } else {
 608                 imxmci_busy_wait_for_status(host, &stat,
 609                                 STATUS_APPL_BUFF_FE,
 610                                 20, "imxmci_cpu_driven_data write");
 611
 612                 while((stat & STATUS_APPL_BUFF_FE) &&
 613                       (host->data_cnt < host->dma_size)) {
 614                         if(burst_len >= host->dma_size - host->data_cnt) {
 615                                 burst_len = host->dma_size - host->data_cnt;
 616                                 host->data_cnt = host->dma_size;
 617                                 trans_done = 1;
 618                         } else {
 619                                 host->data_cnt += burst_len;
 620                         }
 621
 622                         for(i = burst_len; i>0 ; i-=2)
 623                                 MMC_BUFFER_ACCESS = *(host->data_ptr++);
 624
 625                         stat = MMC_STATUS;
 626
 627                         dev_dbg(mmc_dev(host->mmc), "imxmci_cpu_driven_data write burst %d STATUS = 0x%x\n",
 628                                 burst_len, stat);
 629                 }
 630         }
 631
 632         *pstat = stat;
 633
 634         return trans_done;
 635 }
 636
 637 static void imxmci_dma_irq(int dma, void *devid, struct pt_regs *regs)
 638 {
 639         struct imxmci_host *host = devid;
 640         uint32_t stat = MMC_STATUS;
 641
 642         atomic_set(&host->stuck_timeout, 0);
 643         host->status_reg = stat;
 644         set_bit(IMXMCI_PEND_DMA_END_b, &host->pending_events);
 645         tasklet_schedule(&host->tasklet);
 646 }
 647
 648 static irqreturn_t imxmci_irq(int irq, void *devid, struct pt_regs *regs)
 649 {
 650         struct imxmci_host *host = devid;
 651         uint32_t stat = MMC_STATUS;
 652         int handled = 1;
 653
 654         MMC_INT_MASK = host->imask | INT_MASK_SDIO | INT_MASK_AUTO_CARD_DETECT;
 655
 656         atomic_set(&host->stuck_timeout, 0);
 657         host->status_reg = stat;
 658         set_bit(IMXMCI_PEND_IRQ_b, &host->pending_events);
 659         set_bit(IMXMCI_PEND_STARTED_b, &host->pending_events);
 660         tasklet_schedule(&host->tasklet);
 661
 662         return IRQ_RETVAL(handled);;
 663 }
 664
 665 static void imxmci_tasklet_fnc(unsigned long data)
 666 {
 667         struct imxmci_host *host = (struct imxmci_host *)data;
 668         u32 stat;
 669         unsigned int data_dir_mask = 0; /* STATUS_WR_CRC_ERROR_CODE_MASK */
 670         int timeout = 0;
 671
 672         if(atomic_read(&host->stuck_timeout) > 4) {
 673                 char *what;
 674                 timeout = 1;
 675                 stat = MMC_STATUS;
 676                 host->status_reg = stat;
 677                 if (test_bit(IMXMCI_PEND_WAIT_RESP_b, &host->pending_events))
 678                         if (test_bit(IMXMCI_PEND_DMA_DATA_b, &host->pending_events))
 679                                 what = "RESP+DMA";
 680                         else
 681                                 what = "RESP";
 682                 else
 683                         if (test_bit(IMXMCI_PEND_DMA_DATA_b, &host->pending_events))
 684                                 if(test_bit(IMXMCI_PEND_DMA_END_b, &host->pending_events))
 685                                         what = "DATA";
 686                                 else
 687                                         what = "DMA";
 688                         else
 689                                 what = "???";
 690
 691                 dev_err(mmc_dev(host->mmc), "%s TIMEOUT, hardware stucked STATUS = 0x%04x IMASK = 0x%04x\n",
 692                        what, stat, MMC_INT_MASK);
 693                 dev_err(mmc_dev(host->mmc), "CMD_DAT_CONT = 0x%04x, MMC_BLK_LEN = 0x%04x, MMC_NOB = 0x%04x, DMA_CCR = 0x%08x\n",
 694                        MMC_CMD_DAT_CONT, MMC_BLK_LEN, MMC_NOB, CCR(host->dma));
 695                 dev_err(mmc_dev(host->mmc), "CMD%d, bus %d-bit, dma_size = 0x%x\n",
 696                        host->cmd?host->cmd->opcode:0, 1<<host->actual_bus_width, host->dma_size);
 697         }
 698
 699         if(!host->present || timeout)
 700                 host->status_reg = STATUS_TIME_OUT_RESP | STATUS_TIME_OUT_READ |
 701                                     STATUS_CRC_READ_ERR | STATUS_CRC_WRITE_ERR;
 702
 703         if(test_bit(IMXMCI_PEND_IRQ_b, &host->pending_events) || timeout) {
 704                 clear_bit(IMXMCI_PEND_IRQ_b, &host->pending_events);
 705
 706                 stat = MMC_STATUS;
 707                 /*
 708                  * This is not required in theory, but there is chance to miss some flag
 709                  * which clears automatically by mask write, FreeScale original code keeps
 710                  * stat from IRQ time so do I
 711                  */
 712                 stat |= host->status_reg;
 713
 714                 if(test_bit(IMXMCI_PEND_WAIT_RESP_b, &host->pending_events)) {
 715                         imxmci_busy_wait_for_status(host, &stat,
 716                                         STATUS_END_CMD_RESP | STATUS_ERR_MASK,
 717                                         20, "imxmci_tasklet_fnc resp (ERRATUM #4)");
 718                 }
 719
 720                 if(stat & (STATUS_END_CMD_RESP | STATUS_ERR_MASK)) {
 721                         if(test_and_clear_bit(IMXMCI_PEND_WAIT_RESP_b, &host->pending_events))
 722                                 imxmci_cmd_done(host, stat);
 723                         if(host->data && (stat & STATUS_ERR_MASK))
 724                                 imxmci_data_done(host, stat);
 725                 }
 726
 727                 if(test_bit(IMXMCI_PEND_CPU_DATA_b, &host->pending_events)) {
 728                         stat |= MMC_STATUS;
 729                         if(imxmci_cpu_driven_data(host, &stat)){
 730                                 if(test_and_clear_bit(IMXMCI_PEND_WAIT_RESP_b, &host->pending_events))
 731                                         imxmci_cmd_done(host, stat);
 732                                 atomic_clear_mask(IMXMCI_PEND_IRQ_m|IMXMCI_PEND_CPU_DATA_m,
 733                                                         &host->pending_events);
 734                                 imxmci_data_done(host, stat);
 735                         }
 736                 }
 737         }
 738
 739         if(test_bit(IMXMCI_PEND_DMA_END_b, &host->pending_events) &&
 740            !test_bit(IMXMCI_PEND_WAIT_RESP_b, &host->pending_events)) {
 741
 742                 stat = MMC_STATUS;
 743                 /* Same as above */
 744                 stat |= host->status_reg;
 745
 746                 if(host->dma_dir == DMA_TO_DEVICE) {
 747                         data_dir_mask = STATUS_WRITE_OP_DONE;
 748                 } else {
 749                         data_dir_mask = STATUS_DATA_TRANS_DONE;
 750                 }
 751
 752                 if(stat & data_dir_mask) {
 753                         clear_bit(IMXMCI_PEND_DMA_END_b, &host->pending_events);
 754                         imxmci_data_done(host, stat);
 755                 }
 756         }
 757
 758         if(test_and_clear_bit(IMXMCI_PEND_CARD_XCHG_b, &host->pending_events)) {
 759
 760                 if(host->cmd)
 761                         imxmci_cmd_done(host, STATUS_TIME_OUT_RESP);
 762
 763                 if(host->data)
 764                         imxmci_data_done(host, STATUS_TIME_OUT_READ |
 765                                          STATUS_CRC_READ_ERR | STATUS_CRC_WRITE_ERR);
 766
 767                 if(host->req)
 768                         imxmci_finish_request(host, host->req);
 769
 770                 mmc_detect_change(host->mmc, msecs_to_jiffies(100));
 771
 772         }
 773 }
 774
 775 static void imxmci_request(struct mmc_host *mmc, struct mmc_request *req)
 776 {
 777         struct imxmci_host *host = mmc_priv(mmc);
 778         unsigned int cmdat;
 779
 780         WARN_ON(host->req != NULL);
 781
 782         host->req = req;
 783
 784         cmdat = 0;
 785
 786         if (req->data) {
 787                 imxmci_setup_data(host, req->data);
 788
 789                 cmdat |= CMD_DAT_CONT_DATA_ENABLE;
 790
 791                 if (req->data->flags & MMC_DATA_WRITE)
 792                         cmdat |= CMD_DAT_CONT_WRITE;
 793
 794                 if (req->data->flags & MMC_DATA_STREAM) {
 795                         cmdat |= CMD_DAT_CONT_STREAM_BLOCK;
 796                 }
 797         }
 798
 799         imxmci_start_cmd(host, req->cmd, cmdat);
 800 }
 801
 802 #define CLK_RATE 19200000
 803
 804 static void imxmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 805 {
 806         struct imxmci_host *host = mmc_priv(mmc);
 807         int prescaler;
 808
 809         if( ios->bus_width==MMC_BUS_WIDTH_4 ) {
 810                 host->actual_bus_width = MMC_BUS_WIDTH_4;
 811                 imx_gpio_mode(PB11_PF_SD_DAT3);
 812         }else{
 813                 host->actual_bus_width = MMC_BUS_WIDTH_1;
 814                 imx_gpio_mode(GPIO_PORTB | GPIO_IN | GPIO_PUEN | 11);
 815         }
 816
 817         if ( host->power_mode != ios->power_mode ) {
 818                 switch (ios->power_mode) {
 819                 case MMC_POWER_OFF:
 820                         break;
 821                 case MMC_POWER_UP:
 822                         set_bit(IMXMCI_PEND_SET_INIT_b, &host->pending_events);
 823                         break;
 824                 case MMC_POWER_ON:
 825                         break;
 826                 }
 827                 host->power_mode = ios->power_mode;
 828         }
 829
 830         if ( ios->clock ) {
 831                 unsigned int clk;
 832
 833                 /* The prescaler is 5 for PERCLK2 equal to 96MHz
 834                  * then 96MHz / 5 = 19.2 MHz
 835                  */
 836                 clk=imx_get_perclk2();
 837                 prescaler=(clk+(CLK_RATE*7)/8)/CLK_RATE;
 838                 switch(prescaler) {
 839                 case 0:
 840                 case 1: prescaler = 0;
 841                         break;
 842                 case 2: prescaler = 1;
 843                         break;
 844                 case 3: prescaler = 2;
 845                         break;
 846                 case 4: prescaler = 4;
 847                         break;
 848                 default:
 849                 case 5: prescaler = 5;
 850                         break;
 851                 }
 852
 853                 dev_dbg(mmc_dev(host->mmc), "PERCLK2 %d MHz -> prescaler %d\n",
 854                         clk, prescaler);
 855
 856                 for(clk=0; clk<8; clk++) {
 857                         int x;
 858                         x = CLK_RATE / (1<<clk);
 859                         if( x <= ios->clock)
 860                                 break;
 861                 }
 862
 863                 MMC_STR_STP_CLK |= STR_STP_CLK_ENABLE; /* enable controller */
 864
 865                 imxmci_stop_clock(host);
 866                 MMC_CLK_RATE = (prescaler<<3) | clk;
 867                 /*
 868                  * Under my understanding, clock should not be started there, because it would
 869                  * initiate SDHC sequencer and send last or random command into card
 870                  */
 871                 /*imxmci_start_clock(host);*/
 872
 873                 dev_dbg(mmc_dev(host->mmc), "MMC_CLK_RATE: 0x%08x\n", MMC_CLK_RATE);
 874         } else {
 875                 imxmci_stop_clock(host);
 876         }
 877 }
 878
 879 static struct mmc_host_ops imxmci_ops = {
 880         .request        = imxmci_request,
 881         .set_ios        = imxmci_set_ios,
 882 };
 883
 884 static struct resource *platform_device_resource(struct platform_device *dev, unsigned int mask, int nr)
 885 {
 886         int i;
 887
 888         for (i = 0; i < dev->num_resources; i++)
 889                 if (dev->resource[i].flags == mask && nr-- == 0)
 890                         return &dev->resource[i];
 891         return NULL;
 892 }
 893
 894 static int platform_device_irq(struct platform_device *dev, int nr)
 895 {
 896         int i;
 897
 898         for (i = 0; i < dev->num_resources; i++)
 899                 if (dev->resource[i].flags == IORESOURCE_IRQ && nr-- == 0)
 900                         return dev->resource[i].start;
 901         return NO_IRQ;
 902 }
 903
 904 static void imxmci_check_status(unsigned long data)
 905 {
 906         struct imxmci_host *host = (struct imxmci_host *)data;
 907
 908         if( host->pdata->card_present() != host->present ) {
 909                 host->present ^= 1;
 910                 dev_info(mmc_dev(host->mmc), "card %s\n",
 911                       host->present ? "inserted" : "removed");
 912
 913                 set_bit(IMXMCI_PEND_CARD_XCHG_b, &host->pending_events);
 914                 tasklet_schedule(&host->tasklet);
 915         }
 916
 917         if(test_bit(IMXMCI_PEND_WAIT_RESP_b, &host->pending_events) ||
 918            test_bit(IMXMCI_PEND_DMA_DATA_b, &host->pending_events)) {
 919                 atomic_inc(&host->stuck_timeout);
 920                 if(atomic_read(&host->stuck_timeout) > 4)
 921                         tasklet_schedule(&host->tasklet);
 922         } else {
 923                 atomic_set(&host->stuck_timeout, 0);
 924
 925         }
 926
 927         mod_timer(&host->timer, jiffies + (HZ>>1));
 928 }
 929
 930 static int imxmci_probe(struct platform_device *pdev)
 931 {
 932         struct mmc_host *mmc;
 933         struct imxmci_host *host = NULL;
 934         struct resource *r;
 935         int ret = 0, irq;
 936
 937         printk(KERN_INFO "i.MX mmc driver\n");
 938
 939         r = platform_device_resource(pdev, IORESOURCE_MEM, 0);
 940         irq = platform_device_irq(pdev, 0);
 941         if (!r || irq == NO_IRQ)
 942                 return -ENXIO;
 943
 944         r = request_mem_region(r->start, 0x100, "IMXMCI");
 945         if (!r)
 946                 return -EBUSY;
 947
 948         mmc = mmc_alloc_host(sizeof(struct imxmci_host), &pdev->dev);
 949         if (!mmc) {
 950                 ret = -ENOMEM;
 951                 goto out;
 952         }
 953
 954         mmc->ops = &imxmci_ops;
 955         mmc->f_min = 150000;
 956         mmc->f_max = CLK_RATE/2;
 957         mmc->ocr_avail = MMC_VDD_32_33;
 958         mmc->caps |= MMC_CAP_4_BIT_DATA;
 959
 960         /* MMC core transfer sizes tunable parameters */
 961         mmc->max_hw_segs = 64;
 962         mmc->max_phys_segs = 64;
 963         mmc->max_sectors = 64;          /* default 1 << (PAGE_CACHE_SHIFT - 9) */
 964         mmc->max_seg_size = 64*512;     /* default PAGE_CACHE_SIZE */
 965
 966         host = mmc_priv(mmc);
 967         host->mmc = mmc;
 968         host->dma_allocated = 0;
 969         host->pdata = pdev->dev.platform_data;
 970
 971         spin_lock_init(&host->lock);
 972         host->res = r;
 973         host->irq = irq;
 974
 975         imx_gpio_mode(PB8_PF_SD_DAT0);
 976         imx_gpio_mode(PB9_PF_SD_DAT1);
 977         imx_gpio_mode(PB10_PF_SD_DAT2);
 978         /* Configured as GPIO with pull-up to ensure right MCC card mode */
 979         /* Switched to PB11_PF_SD_DAT3 if 4 bit bus is configured */
 980         imx_gpio_mode(GPIO_PORTB | GPIO_IN | GPIO_PUEN | 11);
 981         /* imx_gpio_mode(PB11_PF_SD_DAT3); */
 982         imx_gpio_mode(PB12_PF_SD_CLK);
 983         imx_gpio_mode(PB13_PF_SD_CMD);
 984
 985         imxmci_softreset();
 986
 987         if ( MMC_REV_NO != 0x390 ) {
 988                 dev_err(mmc_dev(host->mmc), "wrong rev.no. 0x%08x. aborting.\n",
 989                         MMC_REV_NO);
 990                 goto out;
 991         }
 992
 993         MMC_READ_TO = 0x2db4; /* recommended in data sheet */
 994
 995         host->imask = IMXMCI_INT_MASK_DEFAULT;
 996         MMC_INT_MASK = host->imask;
 997
 998
 999         if(imx_dma_request_by_prio(&host->dma, DRIVER_NAME, DMA_PRIO_LOW)<0){
1000                 dev_err(mmc_dev(host->mmc), "imx_dma_request_by_prio failed\n");
1001                 ret = -EBUSY;
1002                 goto out;
1003         }
1004         host->dma_allocated=1;
1005         imx_dma_setup_handlers(host->dma, imxmci_dma_irq, NULL, host);
1006
1007         tasklet_init(&host->tasklet, imxmci_tasklet_fnc, (unsigned long)host);
1008         host->status_reg=0;
1009         host->pending_events=0;
1010
1011         ret = request_irq(host->irq, imxmci_irq, 0, DRIVER_NAME, host);
1012         if (ret)
1013                 goto out;
1014
1015         host->present = host->pdata->card_present();
1016         init_timer(&host->timer);
1017         host->timer.data = (unsigned long)host;
1018         host->timer.function = imxmci_check_status;
1019         add_timer(&host->timer);
1020         mod_timer(&host->timer, jiffies + (HZ>>1));
1021
1022         platform_set_drvdata(pdev, mmc);
1023
1024         mmc_add_host(mmc);
1025
1026         return 0;
1027
1028 out:
1029         if (host) {
1030                 if(host->dma_allocated){
1031                         imx_dma_free(host->dma);
1032                         host->dma_allocated=0;
1033                 }
1034         }
1035         if (mmc)
1036                 mmc_free_host(mmc);
1037         release_resource(r);
1038         return ret;
1039 }
1040
1041 static int imxmci_remove(struct platform_device *pdev)
1042 {
1043         struct mmc_host *mmc = platform_get_drvdata(pdev);
1044
1045         platform_set_drvdata(pdev, NULL);
1046
1047         if (mmc) {
1048                 struct imxmci_host *host = mmc_priv(mmc);
1049
1050                 tasklet_disable(&host->tasklet);
1051
1052                 del_timer_sync(&host->timer);
1053                 mmc_remove_host(mmc);
1054
1055                 free_irq(host->irq, host);
1056                 if(host->dma_allocated){
1057                         imx_dma_free(host->dma);
1058                         host->dma_allocated=0;
1059                 }
1060
1061                 tasklet_kill(&host->tasklet);
1062
1063                 release_resource(host->res);
1064
1065                 mmc_free_host(mmc);
1066         }
1067         return 0;
1068 }
1069
1070 #ifdef CONFIG_PM
1071 static int imxmci_suspend(struct platform_device *dev, pm_message_t state)
1072 {
1073         struct mmc_host *mmc = platform_get_drvdata(dev);
1074         int ret = 0;
1075
1076         if (mmc)
1077                 ret = mmc_suspend_host(mmc, state);
1078
1079         return ret;
1080 }
1081
1082 static int imxmci_resume(struct platform_device *dev)
1083 {
1084         struct mmc_host *mmc = platform_get_drvdata(dev);
1085         struct imxmci_host *host;
1086         int ret = 0;
1087
1088         if (mmc) {
1089                 host = mmc_priv(mmc);
1090                 if(host)
1091                         set_bit(IMXMCI_PEND_SET_INIT_b, &host->pending_events);
1092                 ret = mmc_resume_host(mmc);
1093         }
1094
1095         return ret;
1096 }
1097 #else
1098 #define imxmci_suspend  NULL
1099 #define imxmci_resume   NULL
1100 #endif /* CONFIG_PM */
1101
1102 static struct platform_driver imxmci_driver = {
1103         .probe          = imxmci_probe,
1104         .remove         = imxmci_remove,
1105         .suspend        = imxmci_suspend,
1106         .resume         = imxmci_resume,
1107         .driver         = {
1108                 .name           = DRIVER_NAME,
1109         }
1110 };
1111
1112 static int __init imxmci_init(void)
1113 {
1114         return platform_driver_register(&imxmci_driver);
1115 }
1116
1117 static void __exit imxmci_exit(void)
1118 {
1119         platform_driver_unregister(&imxmci_driver);
1120 }
1121
1122 module_init(imxmci_init);
1123 module_exit(imxmci_exit);
1124
1125 MODULE_DESCRIPTION("i.MX Multimedia Card Interface Driver");
1126 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1127 MODULE_LICENSE("GPL");