drivers/mmc/imxmmc.c

   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 #include <linux/config.h>
  29
  30 #ifdef CONFIG_MMC_DEBUG
  31 #define DEBUG
  32 #else
  33 #undef  DEBUG
  34 #endif
  35
  36 #include <linux/module.h>
  37 #include <linux/init.h>
  38 #include <linux/ioport.h>
  39 #include <linux/platform_device.h>
  40 #include <linux/interrupt.h>
  41 #include <linux/blkdev.h>
  42 #include <linux/dma-mapping.h>
  43 #include <linux/mmc/host.h>
  44 #include <linux/mmc/card.h>
  45 #include <linux/mmc/protocol.h>
  46 #include <linux/delay.h>
  47
  48 #include <asm/dma.h>
  49 #include <asm/io.h>
  50 #include <asm/irq.h>
  51 #include <asm/sizes.h>
  52 #include <asm/arch/mmc.h>
  53 #include <asm/arch/imx-dma.h>
  54
  55 #include "imxmmc.h"
  56
  57 #define DRIVER_NAME "imx-mmc"
  58
  59 #define IMXMCI_INT_MASK_DEFAULT (INT_MASK_BUF_READY | INT_MASK_DATA_TRAN | \
  60                       INT_MASK_WRITE_OP_DONE | INT_MASK_END_CMD_RES | \
  61                       INT_MASK_AUTO_CARD_DETECT | INT_MASK_DAT0_EN | INT_MASK_SDIO)
  62
  63 struct imxmci_host {
  64         struct mmc_host         *mmc;
  65         spinlock_t              lock;
  66         struct resource         *res;
  67         int                     irq;
  68         imx_dmach_t             dma;
  69         unsigned int            clkrt;
  70         unsigned int            cmdat;
  71         volatile unsigned int   imask;
  72         unsigned int            power_mode;
  73         unsigned int            present;
  74         struct imxmmc_platform_data *pdata;
  75
  76         struct mmc_request      *req;
  77         struct mmc_command      *cmd;
  78         struct mmc_data         *data;
  79
  80         struct timer_list       timer;
  81         struct tasklet_struct   tasklet;
  82         unsigned int            status_reg;
  83         unsigned long           pending_events;
  84         /* Next to fields are there for CPU driven transfers to overcome SDHC deficiencies */
  85         u16                     *data_ptr;
  86         unsigned int            data_cnt;
  87         atomic_t                stuck_timeout;
  88
  89         unsigned int            dma_nents;
  90         unsigned int            dma_size;
  91         unsigned int            dma_dir;
  92         int                     dma_allocated;
  93
  94         unsigned char           actual_bus_width;
  95 };
  96
  97 #define IMXMCI_PEND_IRQ_b       0
  98 #define IMXMCI_PEND_DMA_END_b   1
  99 #define IMXMCI_PEND_DMA_ERR_b   2
 100 #define IMXMCI_PEND_WAIT_RESP_b 3
 101 #define IMXMCI_PEND_DMA_DATA_b  4
 102 #define IMXMCI_PEND_CPU_DATA_b  5
 103 #define IMXMCI_PEND_CARD_XCHG_b 6
 104 #define IMXMCI_PEND_SET_INIT_b  7
 105 #define IMXMCI_PEND_STARTED_b   8
 106
 107 #define IMXMCI_PEND_IRQ_m       (1 << IMXMCI_PEND_IRQ_b)
 108 #define IMXMCI_PEND_DMA_END_m   (1 << IMXMCI_PEND_DMA_END_b)
 109 #define IMXMCI_PEND_DMA_ERR_m   (1 << IMXMCI_PEND_DMA_ERR_b)
 110 #define IMXMCI_PEND_WAIT_RESP_m (1 << IMXMCI_PEND_WAIT_RESP_b)
 111 #define IMXMCI_PEND_DMA_DATA_m  (1 << IMXMCI_PEND_DMA_DATA_b)
 112 #define IMXMCI_PEND_CPU_DATA_m  (1 << IMXMCI_PEND_CPU_DATA_b)
 113 #define IMXMCI_PEND_CARD_XCHG_m (1 << IMXMCI_PEND_CARD_XCHG_b)
 114 #define IMXMCI_PEND_SET_INIT_m  (1 << IMXMCI_PEND_SET_INIT_b)
 115 #define IMXMCI_PEND_STARTED_m   (1 << IMXMCI_PEND_STARTED_b)
 116
 117 static void imxmci_stop_clock(struct imxmci_host *host)
 118 {
 119         int i = 0;
 120         MMC_STR_STP_CLK &= ~STR_STP_CLK_START_CLK;
 121         while(i < 0x1000) {
 122                 if(!(i & 0x7f))
 123                         MMC_STR_STP_CLK |= STR_STP_CLK_STOP_CLK;
 124
 125                 if(!(MMC_STATUS & STATUS_CARD_BUS_CLK_RUN)) {
 126                         /* Check twice before cut */
 127                         if(!(MMC_STATUS & STATUS_CARD_BUS_CLK_RUN))
 128                                 return;
 129                 }
 130
 131                 i++;
 132         }
 133         dev_dbg(mmc_dev(host->mmc), "imxmci_stop_clock blocked, no luck\n");
 134 }
 135
 136 static int imxmci_start_clock(struct imxmci_host *host)
 137 {
 138         unsigned int trials = 0;
 139         unsigned int delay_limit = 128;
 140         unsigned long flags;
 141
 142         MMC_STR_STP_CLK &= ~STR_STP_CLK_STOP_CLK;
 143
 144         clear_bit(IMXMCI_PEND_STARTED_b, &host->pending_events);
 145
 146         /*
 147          * Command start of the clock, this usually succeeds in less
 148          * then 6 delay loops, but during card detection (low clockrate)
 149          * it takes up to 5000 delay loops and sometimes fails for the first time
 150          */
 151         MMC_STR_STP_CLK |= STR_STP_CLK_START_CLK;
 152
 153         do {
 154                 unsigned int delay = delay_limit;
 155
 156                 while(delay--){
 157                         if(MMC_STATUS & STATUS_CARD_BUS_CLK_RUN)
 158                                 /* Check twice before cut */
 159                                 if(MMC_STATUS & STATUS_CARD_BUS_CLK_RUN)
 160                                         return 0;
 161
 162                         if(test_bit(IMXMCI_PEND_STARTED_b, &host->pending_events))
 163                                 return 0;
 164                 }
 165
 166                 local_irq_save(flags);
 167                 /*
 168                  * Ensure, that request is not doubled under all possible circumstances.
 169                  * It is possible, that cock running state is missed, because some other
 170                  * IRQ or schedule delays this function execution and the clocks has
 171                  * been already stopped by other means (response processing, SDHC HW)
 172                  */
 173                 if(!test_bit(IMXMCI_PEND_STARTED_b, &host->pending_events))
 174                         MMC_STR_STP_CLK |= STR_STP_CLK_START_CLK;
 175                 local_irq_restore(flags);
 176
 177         } while(++trials<256);
 178
 179         dev_err(mmc_dev(host->mmc), "imxmci_start_clock blocked, no luck\n");
 180
 181         return -1;
 182 }
 183
 184 static void imxmci_softreset(void)
 185 {
 186         /* reset sequence */
 187         MMC_STR_STP_CLK = 0x8;
 188         MMC_STR_STP_CLK = 0xD;
 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         MMC_STR_STP_CLK = 0x5;
 197
 198         MMC_RES_TO = 0xff;
 199         MMC_BLK_LEN = 512;
 200         MMC_NOB = 1;
 201 }
 202
 203 static int imxmci_busy_wait_for_status(struct imxmci_host *host,
 204                         unsigned int *pstat, unsigned int stat_mask,
 205                         int timeout, const char *where)
 206 {
 207         int loops=0;
 208         while(!(*pstat & stat_mask)) {
 209                 loops+=2;
 210                 if(loops >= timeout) {
 211                         dev_dbg(mmc_dev(host->mmc), "busy wait timeout in %s, STATUS = 0x%x (0x%x)\n",
 212                                 where, *pstat, stat_mask);
 213                         return -1;
 214                 }
 215                 udelay(2);
 216                 *pstat |= MMC_STATUS;
 217         }
 218         if(!loops)
 219                 return 0;
 220
 221         /* The busy-wait is expected there for clock <8MHz due to SDHC hardware flaws */
 222         if(!(stat_mask & STATUS_END_CMD_RESP) || (host->mmc->ios.clock>=8000000))
 223                 dev_info(mmc_dev(host->mmc), "busy wait for %d usec in %s, STATUS = 0x%x (0x%x)\n",
 224                         loops, where, *pstat, stat_mask);
 225         return loops;
 226 }
 227
 228 static void imxmci_setup_data(struct imxmci_host *host, struct mmc_data *data)
 229 {
 230         unsigned int nob = data->blocks;
 231         unsigned int blksz = 1 << data->blksz_bits;
 232         unsigned int datasz = nob * blksz;
 233         int i;
 234
 235         if (data->flags & MMC_DATA_STREAM)
 236                 nob = 0xffff;
 237
 238         host->data = data;
 239         data->bytes_xfered = 0;
 240
 241         MMC_NOB = nob;
 242         MMC_BLK_LEN = blksz;
 243
 244         /*
 245          * DMA cannot be used for small block sizes, we have to use CPU driven transfers otherwise.
 246          * We are in big troubles for non-512 byte transfers according to note in the paragraph
 247          * 20.6.7 of User Manual anyway, but we need to be able to transfer SCR at least.
 248          * The situation is even more complex in reality. The SDHC in not able to handle wll
 249          * partial FIFO fills and reads. The length has to be rounded up to burst size multiple.
 250          * This is required for SCR read at least.
 251          */
 252         if (datasz < 64) {
 253                 host->dma_size = datasz;
 254                 if (data->flags & MMC_DATA_READ) {
 255                         host->dma_dir = DMA_FROM_DEVICE;
 256
 257                         /* Hack to enable read SCR */
 258                         if(datasz < 16) {
 259                                 MMC_NOB = 1;
 260                                 MMC_BLK_LEN = 16;
 261                         }
 262                 } else {
 263                         host->dma_dir = DMA_TO_DEVICE;
 264                 }
 265
 266                 /* Convert back to virtual address */
 267                 host->data_ptr = (u16*)(page_address(data->sg->page) + data->sg->offset);
 268                 host->data_cnt = 0;
 269
 270                 clear_bit(IMXMCI_PEND_DMA_DATA_b, &host->pending_events);
 271                 set_bit(IMXMCI_PEND_CPU_DATA_b, &host->pending_events);
 272
 273                 return;
 274         }
 275
 276         if (data->flags & MMC_DATA_READ) {
 277                 host->dma_dir = DMA_FROM_DEVICE;
 278                 host->dma_nents = dma_map_sg(mmc_dev(host->mmc), data->sg,
 279                                                 data->sg_len,  host->dma_dir);
 280
 281                 imx_dma_setup_sg(host->dma, data->sg, data->sg_len, datasz,
 282                         host->res->start + MMC_BUFFER_ACCESS_OFS, DMA_MODE_READ);
 283
 284                 /*imx_dma_setup_mem2dev_ccr(host->dma, DMA_MODE_READ, IMX_DMA_WIDTH_16, CCR_REN);*/
 285                 CCR(host->dma) = CCR_DMOD_LINEAR | CCR_DSIZ_32 | CCR_SMOD_FIFO | CCR_SSIZ_16 | CCR_REN;
 286         } else {
 287                 host->dma_dir = DMA_TO_DEVICE;
 288
 289                 host->dma_nents = dma_map_sg(mmc_dev(host->mmc), data->sg,
 290                                                 data->sg_len,  host->dma_dir);
 291
 292                 imx_dma_setup_sg(host->dma, data->sg, data->sg_len, datasz,
 293                         host->res->start + MMC_BUFFER_ACCESS_OFS, DMA_MODE_WRITE);
 294
 295                 /*imx_dma_setup_mem2dev_ccr(host->dma, DMA_MODE_WRITE, IMX_DMA_WIDTH_16, CCR_REN);*/
 296                 CCR(host->dma) = CCR_SMOD_LINEAR | CCR_SSIZ_32 | CCR_DMOD_FIFO | CCR_DSIZ_16 | CCR_REN;
 297         }
 298
 299 #if 1   /* This code is there only for consistency checking and can be disabled in future */
 300         host->dma_size = 0;
 301         for(i=0; i<host->dma_nents; i++)
 302                 host->dma_size+=data->sg[i].length;
 303
 304         if (datasz > host->dma_size) {
 305                 dev_err(mmc_dev(host->mmc), "imxmci_setup_data datasz 0x%x > 0x%x dm_size\n",
 306                        datasz, host->dma_size);
 307         }
 308 #endif
 309
 310         host->dma_size = datasz;
 311
 312         wmb();
 313
 314         if(host->actual_bus_width == MMC_BUS_WIDTH_4)
 315                 BLR(host->dma) = 0;     /* burst 64 byte read / 64 bytes write */
 316         else
 317                 BLR(host->dma) = 16;    /* burst 16 byte read / 16 bytes write */
 318
 319         RSSR(host->dma) = DMA_REQ_SDHC;
 320
 321         set_bit(IMXMCI_PEND_DMA_DATA_b, &host->pending_events);
 322         clear_bit(IMXMCI_PEND_CPU_DATA_b, &host->pending_events);
 323
 324         /* start DMA engine for read, write is delayed after initial response */
 325         if (host->dma_dir == DMA_FROM_DEVICE) {
 326                 imx_dma_enable(host->dma);
 327         }
 328 }
 329
 330 static void imxmci_start_cmd(struct imxmci_host *host, struct mmc_command *cmd, unsigned int cmdat)
 331 {
 332         unsigned long flags;
 333         u32 imask;
 334
 335         WARN_ON(host->cmd != NULL);
 336         host->cmd = cmd;
 337
 338         /* Ensure, that clock are stopped else command programming and start fails */
 339         imxmci_stop_clock(host);
 340
 341         if (cmd->flags & MMC_RSP_BUSY)
 342                 cmdat |= CMD_DAT_CONT_BUSY;
 343
 344         switch (mmc_resp_type(cmd)) {
 345         case MMC_RSP_R1: /* short CRC, OPCODE */
 346         case MMC_RSP_R1B:/* short CRC, OPCODE, BUSY */
 347                 cmdat |= CMD_DAT_CONT_RESPONSE_FORMAT_R1;
 348                 break;
 349         case MMC_RSP_R2: /* long 136 bit + CRC */
 350                 cmdat |= CMD_DAT_CONT_RESPONSE_FORMAT_R2;
 351                 break;
 352         case MMC_RSP_R3: /* short */
 353                 cmdat |= CMD_DAT_CONT_RESPONSE_FORMAT_R3;
 354                 break;
 355         case MMC_RSP_R6: /* short CRC */
 356                 cmdat |= CMD_DAT_CONT_RESPONSE_FORMAT_R6;
 357                 break;
 358         default:
 359                 break;
 360         }
 361
 362         if ( test_and_clear_bit(IMXMCI_PEND_SET_INIT_b, &host->pending_events) )
 363                 cmdat |= CMD_DAT_CONT_INIT; /* This command needs init */
 364
 365         if ( host->actual_bus_width == MMC_BUS_WIDTH_4 )
 366                 cmdat |= CMD_DAT_CONT_BUS_WIDTH_4;
 367
 368         MMC_CMD = cmd->opcode;
 369         MMC_ARGH = cmd->arg >> 16;
 370         MMC_ARGL = cmd->arg & 0xffff;
 371         MMC_CMD_DAT_CONT = cmdat;
 372
 373         atomic_set(&host->stuck_timeout, 0);
 374         set_bit(IMXMCI_PEND_WAIT_RESP_b, &host->pending_events);
 375
 376
 377         imask = IMXMCI_INT_MASK_DEFAULT;
 378         imask &= ~INT_MASK_END_CMD_RES;
 379         if ( cmdat & CMD_DAT_CONT_DATA_ENABLE ) {
 380                 /*imask &= ~INT_MASK_BUF_READY;*/
 381                 imask &= ~INT_MASK_DATA_TRAN;
 382                 if ( cmdat & CMD_DAT_CONT_WRITE )
 383                         imask &= ~INT_MASK_WRITE_OP_DONE;
 384                 if(test_bit(IMXMCI_PEND_CPU_DATA_b, &host->pending_events))
 385                         imask &= ~INT_MASK_BUF_READY;
 386         }
 387
 388         spin_lock_irqsave(&host->lock, flags);
 389         host->imask = imask;
 390         MMC_INT_MASK = host->imask;
 391         spin_unlock_irqrestore(&host->lock, flags);
 392
 393         dev_dbg(mmc_dev(host->mmc), "CMD%02d (0x%02x) mask set to 0x%04x\n",
 394                 cmd->opcode, cmd->opcode, imask);
 395
 396         imxmci_start_clock(host);
 397 }
 398
 399 static void imxmci_finish_request(struct imxmci_host *host, struct mmc_request *req)
 400 {
 401         unsigned long flags;
 402
 403         spin_lock_irqsave(&host->lock, flags);
 404
 405         host->pending_events &= ~(IMXMCI_PEND_WAIT_RESP_m | IMXMCI_PEND_DMA_END_m |
 406                         IMXMCI_PEND_DMA_DATA_m | IMXMCI_PEND_CPU_DATA_m);
 407
 408         host->imask = IMXMCI_INT_MASK_DEFAULT;
 409         MMC_INT_MASK = host->imask;
 410
 411         spin_unlock_irqrestore(&host->lock, flags);
 412
 413         host->req = NULL;
 414         host->cmd = NULL;
 415         host->data = NULL;
 416         mmc_request_done(host->mmc, req);
 417 }
 418
 419 static int imxmci_finish_data(struct imxmci_host *host, unsigned int stat)
 420 {
 421         struct mmc_data *data = host->data;
 422         int data_error;
 423
 424         if(test_and_clear_bit(IMXMCI_PEND_DMA_DATA_b, &host->pending_events)){
 425                 imx_dma_disable(host->dma);
 426                 dma_unmap_sg(mmc_dev(host->mmc), data->sg, host->dma_nents,
 427                              host->dma_dir);
 428         }
 429
 430         if ( stat & STATUS_ERR_MASK ) {
 431                 dev_dbg(mmc_dev(host->mmc), "request failed. status: 0x%08x\n",stat);
 432                 if(stat & (STATUS_CRC_READ_ERR | STATUS_CRC_WRITE_ERR))
 433                         data->error = MMC_ERR_BADCRC;
 434                 else if(stat & STATUS_TIME_OUT_READ)
 435                         data->error = MMC_ERR_TIMEOUT;
 436                 else
 437                         data->error = MMC_ERR_FAILED;
 438         } else {
 439                 data->bytes_xfered = host->dma_size;
 440         }
 441
 442         data_error = data->error;
 443
 444         host->data = NULL;
 445
 446         return data_error;
 447 }
 448
 449 static int imxmci_cmd_done(struct imxmci_host *host, unsigned int stat)
 450 {
 451         struct mmc_command *cmd = host->cmd;
 452         int i;
 453         u32 a,b,c;
 454         struct mmc_data *data = host->data;
 455
 456         if (!cmd)
 457                 return 0;
 458
 459         host->cmd = NULL;
 460
 461         if (stat & STATUS_TIME_OUT_RESP) {
 462                 dev_dbg(mmc_dev(host->mmc), "CMD TIMEOUT\n");
 463                 cmd->error = MMC_ERR_TIMEOUT;
 464         } else if (stat & STATUS_RESP_CRC_ERR && cmd->flags & MMC_RSP_CRC) {
 465                 dev_dbg(mmc_dev(host->mmc), "cmd crc error\n");
 466                 cmd->error = MMC_ERR_BADCRC;
 467         }
 468
 469         if(cmd->flags & MMC_RSP_PRESENT) {
 470                 if(cmd->flags & MMC_RSP_136) {
 471                         for (i = 0; i < 4; i++) {
 472                                 u32 a = MMC_RES_FIFO & 0xffff;
 473                                 u32 b = MMC_RES_FIFO & 0xffff;
 474                                 cmd->resp[i] = a<<16 | b;
 475                         }
 476                 } else {
 477                         a = MMC_RES_FIFO & 0xffff;
 478                         b = MMC_RES_FIFO & 0xffff;
 479                         c = MMC_RES_FIFO & 0xffff;
 480                         cmd->resp[0] = a<<24 | b<<8 | c>>8;
 481                 }
 482         }
 483
 484         dev_dbg(mmc_dev(host->mmc), "RESP 0x%08x, 0x%08x, 0x%08x, 0x%08x, error %d\n",
 485                 cmd->resp[0], cmd->resp[1], cmd->resp[2], cmd->resp[3], cmd->error);
 486
 487         if (data && (cmd->error == MMC_ERR_NONE) && !(stat & STATUS_ERR_MASK)) {
 488                 if (host->req->data->flags & MMC_DATA_WRITE) {
 489
 490                         /* Wait for FIFO to be empty before starting DMA write */
 491
 492                         stat = MMC_STATUS;
 493                         if(imxmci_busy_wait_for_status(host, &stat,
 494                                 STATUS_APPL_BUFF_FE,
 495                                 40, "imxmci_cmd_done DMA WR") < 0) {
 496                                 cmd->error = MMC_ERR_FIFO;
 497                                 imxmci_finish_data(host, stat);
 498                                 if(host->req)
 499                                         imxmci_finish_request(host, host->req);
 500                                 dev_warn(mmc_dev(host->mmc), "STATUS = 0x%04x\n",
 501                                        stat);
 502                                 return 0;
 503                         }
 504
 505                         if(test_bit(IMXMCI_PEND_DMA_DATA_b, &host->pending_events)) {
 506                                 imx_dma_enable(host->dma);
 507                         }
 508                 }
 509         } else {
 510                 struct mmc_request *req;
 511                 imxmci_stop_clock(host);
 512                 req = host->req;
 513
 514                 if(data)
 515                         imxmci_finish_data(host, stat);
 516
 517                 if( req ) {
 518                         imxmci_finish_request(host, req);
 519                 } else {
 520                         dev_warn(mmc_dev(host->mmc), "imxmci_cmd_done: no request to finish\n");
 521                 }
 522         }
 523
 524         return 1;
 525 }
 526
 527 static int imxmci_data_done(struct imxmci_host *host, unsigned int stat)
 528 {
 529         struct mmc_data *data = host->data;
 530         int data_error;
 531
 532         if (!data)
 533                 return 0;
 534
 535         data_error = imxmci_finish_data(host, stat);
 536
 537         if (host->req->stop) {
 538                 imxmci_stop_clock(host);
 539                 imxmci_start_cmd(host, host->req->stop, 0);
 540         } else {
 541                 struct mmc_request *req;
 542                 req = host->req;
 543                 if( req ) {
 544                         imxmci_finish_request(host, req);
 545                 } else {
 546                         dev_warn(mmc_dev(host->mmc), "imxmci_data_done: no request to finish\n");
 547                 }
 548         }
 549
 550         return 1;
 551 }
 552
 553 static int imxmci_cpu_driven_data(struct imxmci_host *host, unsigned int *pstat)
 554 {
 555         int i;
 556         int burst_len;
 557         int flush_len;
 558         int trans_done = 0;
 559         unsigned int stat = *pstat;
 560
 561         if(host->actual_bus_width != MMC_BUS_WIDTH_4)
 562                 burst_len = 16;
 563         else
 564                 burst_len = 64;
 565
 566         /* This is unfortunately required */
 567         dev_dbg(mmc_dev(host->mmc), "imxmci_cpu_driven_data running STATUS = 0x%x\n",
 568                 stat);
 569
 570         if(host->dma_dir == DMA_FROM_DEVICE) {
 571                 imxmci_busy_wait_for_status(host, &stat,
 572                                 STATUS_APPL_BUFF_FF | STATUS_DATA_TRANS_DONE,
 573                                 20, "imxmci_cpu_driven_data read");
 574
 575                 while((stat & (STATUS_APPL_BUFF_FF |  STATUS_DATA_TRANS_DONE)) &&
 576                       (host->data_cnt < host->dma_size)) {
 577                         if(burst_len >= host->dma_size - host->data_cnt) {
 578                                 flush_len = burst_len;
 579                                 burst_len = host->dma_size - host->data_cnt;
 580                                 flush_len -= burst_len;
 581                                 host->data_cnt = host->dma_size;
 582                                 trans_done = 1;
 583                         } else {
 584                                 flush_len = 0;
 585                                 host->data_cnt += burst_len;
 586                         }
 587
 588                         for(i = burst_len; i>=2 ; i-=2) {
 589                                 *(host->data_ptr++) = MMC_BUFFER_ACCESS;
 590                                 udelay(20);     /* required for clocks < 8MHz*/
 591                         }
 592
 593                         if(i == 1)
 594                                 *(u8*)(host->data_ptr) = MMC_BUFFER_ACCESS;
 595
 596                         stat = MMC_STATUS;
 597
 598                         /* Flush extra bytes from FIFO */
 599                         while(flush_len && !(stat & STATUS_DATA_TRANS_DONE)){
 600                                 i = MMC_BUFFER_ACCESS;
 601                                 stat = MMC_STATUS;
 602                                 stat &= ~STATUS_CRC_READ_ERR; /* Stupid but required there */
 603                         }
 604
 605                         dev_dbg(mmc_dev(host->mmc), "imxmci_cpu_driven_data read burst %d STATUS = 0x%x\n",
 606                                 burst_len, stat);
 607                 }
 608         } else {
 609                 imxmci_busy_wait_for_status(host, &stat,
 610                                 STATUS_APPL_BUFF_FE,
 611                                 20, "imxmci_cpu_driven_data write");
 612
 613                 while((stat & STATUS_APPL_BUFF_FE) &&
 614                       (host->data_cnt < host->dma_size)) {
 615                         if(burst_len >= host->dma_size - host->data_cnt) {
 616                                 burst_len = host->dma_size - host->data_cnt;
 617                                 host->data_cnt = host->dma_size;
 618                                 trans_done = 1;
 619                         } else {
 620                                 host->data_cnt += burst_len;
 621                         }
 622
 623                         for(i = burst_len; i>0 ; i-=2)
 624                                 MMC_BUFFER_ACCESS = *(host->data_ptr++);
 625
 626                         stat = MMC_STATUS;
 627
 628                         dev_dbg(mmc_dev(host->mmc), "imxmci_cpu_driven_data write burst %d STATUS = 0x%x\n",
 629                                 burst_len, stat);
 630                 }
 631         }
 632
 633         *pstat = stat;
 634
 635         return trans_done;
 636 }
 637
 638 static void imxmci_dma_irq(int dma, void *devid, struct pt_regs *regs)
 639 {
 640         struct imxmci_host *host = devid;
 641         uint32_t stat = MMC_STATUS;
 642
 643         atomic_set(&host->stuck_timeout, 0);
 644         host->status_reg = stat;
 645         set_bit(IMXMCI_PEND_DMA_END_b, &host->pending_events);
 646         tasklet_schedule(&host->tasklet);
 647 }
 648
 649 static irqreturn_t imxmci_irq(int irq, void *devid, struct pt_regs *regs)
 650 {
 651         struct imxmci_host *host = devid;
 652         uint32_t stat = MMC_STATUS;
 653         int handled = 1;
 654
 655         MMC_INT_MASK = host->imask | INT_MASK_SDIO | INT_MASK_AUTO_CARD_DETECT;
 656
 657         atomic_set(&host->stuck_timeout, 0);
 658         host->status_reg = stat;
 659         set_bit(IMXMCI_PEND_IRQ_b, &host->pending_events);
 660         set_bit(IMXMCI_PEND_STARTED_b, &host->pending_events);
 661         tasklet_schedule(&host->tasklet);
 662
 663         return IRQ_RETVAL(handled);;
 664 }
 665
 666 static void imxmci_tasklet_fnc(unsigned long data)
 667 {
 668         struct imxmci_host *host = (struct imxmci_host *)data;
 669         u32 stat;
 670         unsigned int data_dir_mask = 0; /* STATUS_WR_CRC_ERROR_CODE_MASK */
 671         int timeout = 0;
 672
 673         if(atomic_read(&host->stuck_timeout) > 4) {
 674                 char *what;
 675                 timeout = 1;
 676                 stat = MMC_STATUS;
 677                 host->status_reg = stat;
 678                 if (test_bit(IMXMCI_PEND_WAIT_RESP_b, &host->pending_events))
 679                         if (test_bit(IMXMCI_PEND_DMA_DATA_b, &host->pending_events))
 680                                 what = "RESP+DMA";
 681                         else
 682                                 what = "RESP";
 683                 else
 684                         if (test_bit(IMXMCI_PEND_DMA_DATA_b, &host->pending_events))
 685                                 if(test_bit(IMXMCI_PEND_DMA_END_b, &host->pending_events))
 686                                         what = "DATA";
 687                                 else
 688                                         what = "DMA";
 689                         else
 690                                 what = "???";
 691
 692                 dev_err(mmc_dev(host->mmc), "%s TIMEOUT, hardware stucked STATUS = 0x%04x IMASK = 0x%04x\n",
 693                        what, stat, MMC_INT_MASK);
 694                 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",
 695                        MMC_CMD_DAT_CONT, MMC_BLK_LEN, MMC_NOB, CCR(host->dma));
 696                 dev_err(mmc_dev(host->mmc), "CMD%d, bus %d-bit, dma_size = 0x%x\n",
 697                        host->cmd?host->cmd->opcode:0, 1<<host->actual_bus_width, host->dma_size);
 698         }
 699
 700         if(!host->present || timeout)
 701                 host->status_reg = STATUS_TIME_OUT_RESP | STATUS_TIME_OUT_READ |
 702                                     STATUS_CRC_READ_ERR | STATUS_CRC_WRITE_ERR;
 703
 704         if(test_bit(IMXMCI_PEND_IRQ_b, &host->pending_events) || timeout) {
 705                 clear_bit(IMXMCI_PEND_IRQ_b, &host->pending_events);
 706
 707                 stat = MMC_STATUS;
 708                 /*
 709                  * This is not required in theory, but there is chance to miss some flag
 710                  * which clears automatically by mask write, FreeScale original code keeps
 711                  * stat from IRQ time so do I
 712                  */
 713                 stat |= host->status_reg;
 714
 715                 if(test_bit(IMXMCI_PEND_WAIT_RESP_b, &host->pending_events)) {
 716                         imxmci_busy_wait_for_status(host, &stat,
 717                                         STATUS_END_CMD_RESP | STATUS_ERR_MASK,
 718                                         20, "imxmci_tasklet_fnc resp (ERRATUM #4)");
 719                 }
 720
 721                 if(stat & (STATUS_END_CMD_RESP | STATUS_ERR_MASK)) {
 722                         if(test_and_clear_bit(IMXMCI_PEND_WAIT_RESP_b, &host->pending_events))
 723                                 imxmci_cmd_done(host, stat);
 724                         if(host->data && (stat & STATUS_ERR_MASK))
 725                                 imxmci_data_done(host, stat);
 726                 }
 727
 728                 if(test_bit(IMXMCI_PEND_CPU_DATA_b, &host->pending_events)) {
 729                         stat |= MMC_STATUS;
 730                         if(imxmci_cpu_driven_data(host, &stat)){
 731                                 if(test_and_clear_bit(IMXMCI_PEND_WAIT_RESP_b, &host->pending_events))
 732                                         imxmci_cmd_done(host, stat);
 733                                 atomic_clear_mask(IMXMCI_PEND_IRQ_m|IMXMCI_PEND_CPU_DATA_m,
 734                                                         &host->pending_events);
 735                                 imxmci_data_done(host, stat);
 736                         }
 737                 }
 738         }
 739
 740         if(test_bit(IMXMCI_PEND_DMA_END_b, &host->pending_events) &&
 741            !test_bit(IMXMCI_PEND_WAIT_RESP_b, &host->pending_events)) {
 742
 743                 stat = MMC_STATUS;
 744                 /* Same as above */
 745                 stat |= host->status_reg;
 746
 747                 if(host->dma_dir == DMA_TO_DEVICE) {
 748                         data_dir_mask = STATUS_WRITE_OP_DONE;
 749                 } else {
 750                         data_dir_mask = STATUS_DATA_TRANS_DONE;
 751                 }
 752
 753                 if(stat & data_dir_mask) {
 754                         clear_bit(IMXMCI_PEND_DMA_END_b, &host->pending_events);
 755                         imxmci_data_done(host, stat);
 756                 }
 757         }
 758
 759         if(test_and_clear_bit(IMXMCI_PEND_CARD_XCHG_b, &host->pending_events)) {
 760
 761                 if(host->cmd)
 762                         imxmci_cmd_done(host, STATUS_TIME_OUT_RESP);
 763
 764                 if(host->data)
 765                         imxmci_data_done(host, STATUS_TIME_OUT_READ |
 766                                          STATUS_CRC_READ_ERR | STATUS_CRC_WRITE_ERR);
 767
 768                 if(host->req)
 769                         imxmci_finish_request(host, host->req);
 770
 771                 mmc_detect_change(host->mmc, msecs_to_jiffies(100));
 772
 773         }
 774 }
 775
 776 static void imxmci_request(struct mmc_host *mmc, struct mmc_request *req)
 777 {
 778         struct imxmci_host *host = mmc_priv(mmc);
 779         unsigned int cmdat;
 780
 781         WARN_ON(host->req != NULL);
 782
 783         host->req = req;
 784
 785         cmdat = 0;
 786
 787         if (req->data) {
 788                 imxmci_setup_data(host, req->data);
 789
 790                 cmdat |= CMD_DAT_CONT_DATA_ENABLE;
 791
 792                 if (req->data->flags & MMC_DATA_WRITE)
 793                         cmdat |= CMD_DAT_CONT_WRITE;
 794
 795                 if (req->data->flags & MMC_DATA_STREAM) {
 796                         cmdat |= CMD_DAT_CONT_STREAM_BLOCK;
 797                 }
 798         }
 799
 800         imxmci_start_cmd(host, req->cmd, cmdat);
 801 }
 802
 803 #define CLK_RATE 19200000
 804
 805 static void imxmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 806 {
 807         struct imxmci_host *host = mmc_priv(mmc);
 808         int prescaler;
 809
 810         if( ios->bus_width==MMC_BUS_WIDTH_4 ) {
 811                 host->actual_bus_width = MMC_BUS_WIDTH_4;
 812                 imx_gpio_mode(PB11_PF_SD_DAT3);
 813         }else{
 814                 host->actual_bus_width = MMC_BUS_WIDTH_1;
 815                 imx_gpio_mode(GPIO_PORTB | GPIO_IN | GPIO_PUEN | 11);
 816         }
 817
 818         if ( host->power_mode != ios->power_mode ) {
 819                 switch (ios->power_mode) {
 820                 case MMC_POWER_OFF:
 821                         break;
 822                 case MMC_POWER_UP:
 823                         set_bit(IMXMCI_PEND_SET_INIT_b, &host->pending_events);
 824                         break;
 825                 case MMC_POWER_ON:
 826                         break;
 827                 }
 828                 host->power_mode = ios->power_mode;
 829         }
 830
 831         if ( ios->clock ) {
 832                 unsigned int clk;
 833
 834                 /* The prescaler is 5 for PERCLK2 equal to 96MHz
 835                  * then 96MHz / 5 = 19.2 MHz
 836                  */
 837                 clk=imx_get_perclk2();
 838                 prescaler=(clk+(CLK_RATE*7)/8)/CLK_RATE;
 839                 switch(prescaler) {
 840                 case 0:
 841                 case 1: prescaler = 0;
 842                         break;
 843                 case 2: prescaler = 1;
 844                         break;
 845                 case 3: prescaler = 2;
 846                         break;
 847                 case 4: prescaler = 4;
 848                         break;
 849                 default:
 850                 case 5: prescaler = 5;
 851                         break;
 852                 }
 853
 854                 dev_dbg(mmc_dev(host->mmc), "PERCLK2 %d MHz -> prescaler %d\n",
 855                         clk, prescaler);
 856
 857                 for(clk=0; clk<8; clk++) {
 858                         int x;
 859                         x = CLK_RATE / (1<<clk);
 860                         if( x <= ios->clock)
 861                                 break;
 862                 }
 863
 864                 MMC_STR_STP_CLK |= STR_STP_CLK_ENABLE; /* enable controller */
 865
 866                 imxmci_stop_clock(host);
 867                 MMC_CLK_RATE = (prescaler<<3) | clk;
 868                 /*
 869                  * Under my understanding, clock should not be started there, because it would
 870                  * initiate SDHC sequencer and send last or random command into card
 871                  */
 872                 /*imxmci_start_clock(host);*/
 873
 874                 dev_dbg(mmc_dev(host->mmc), "MMC_CLK_RATE: 0x%08x\n", MMC_CLK_RATE);
 875         } else {
 876                 imxmci_stop_clock(host);
 877         }
 878 }
 879
 880 static struct mmc_host_ops imxmci_ops = {
 881         .request        = imxmci_request,
 882         .set_ios        = imxmci_set_ios,
 883 };
 884
 885 static struct resource *platform_device_resource(struct platform_device *dev, unsigned int mask, int nr)
 886 {
 887         int i;
 888
 889         for (i = 0; i < dev->num_resources; i++)
 890                 if (dev->resource[i].flags == mask && nr-- == 0)
 891                         return &dev->resource[i];
 892         return NULL;
 893 }
 894
 895 static int platform_device_irq(struct platform_device *dev, int nr)
 896 {
 897         int i;
 898
 899         for (i = 0; i < dev->num_resources; i++)
 900                 if (dev->resource[i].flags == IORESOURCE_IRQ && nr-- == 0)
 901                         return dev->resource[i].start;
 902         return NO_IRQ;
 903 }
 904
 905 static void imxmci_check_status(unsigned long data)
 906 {
 907         struct imxmci_host *host = (struct imxmci_host *)data;
 908
 909         if( host->pdata->card_present() != host->present ) {
 910                 host->present ^= 1;
 911                 dev_info(mmc_dev(host->mmc), "card %s\n",
 912                       host->present ? "inserted" : "removed");
 913
 914                 set_bit(IMXMCI_PEND_CARD_XCHG_b, &host->pending_events);
 915                 tasklet_schedule(&host->tasklet);
 916         }
 917
 918         if(test_bit(IMXMCI_PEND_WAIT_RESP_b, &host->pending_events) ||
 919            test_bit(IMXMCI_PEND_DMA_DATA_b, &host->pending_events)) {
 920                 atomic_inc(&host->stuck_timeout);
 921                 if(atomic_read(&host->stuck_timeout) > 4)
 922                         tasklet_schedule(&host->tasklet);
 923         } else {
 924                 atomic_set(&host->stuck_timeout, 0);
 925
 926         }
 927
 928         mod_timer(&host->timer, jiffies + (HZ>>1));
 929 }
 930
 931 static int imxmci_probe(struct platform_device *pdev)
 932 {
 933         struct mmc_host *mmc;
 934         struct imxmci_host *host = NULL;
 935         struct resource *r;
 936         int ret = 0, irq;
 937
 938         printk(KERN_INFO "i.MX mmc driver\n");
 939
 940         r = platform_device_resource(pdev, IORESOURCE_MEM, 0);
 941         irq = platform_device_irq(pdev, 0);
 942         if (!r || irq == NO_IRQ)
 943                 return -ENXIO;
 944
 945         r = request_mem_region(r->start, 0x100, "IMXMCI");
 946         if (!r)
 947                 return -EBUSY;
 948
 949         mmc = mmc_alloc_host(sizeof(struct imxmci_host), &pdev->dev);
 950         if (!mmc) {
 951                 ret = -ENOMEM;
 952                 goto out;
 953         }
 954
 955         mmc->ops = &imxmci_ops;
 956         mmc->f_min = 150000;
 957         mmc->f_max = CLK_RATE/2;
 958         mmc->ocr_avail = MMC_VDD_32_33;
 959         mmc->caps |= MMC_CAP_4_BIT_DATA;
 960
 961         /* MMC core transfer sizes tunable parameters */
 962         mmc->max_hw_segs = 64;
 963         mmc->max_phys_segs = 64;
 964         mmc->max_sectors = 64;          /* default 1 << (PAGE_CACHE_SHIFT - 9) */
 965         mmc->max_seg_size = 64*512;     /* default PAGE_CACHE_SIZE */
 966
 967         host = mmc_priv(mmc);
 968         host->mmc = mmc;
 969         host->dma_allocated = 0;
 970         host->pdata = pdev->dev.platform_data;
 971
 972         spin_lock_init(&host->lock);
 973         host->res = r;
 974         host->irq = irq;
 975
 976         imx_gpio_mode(PB8_PF_SD_DAT0);
 977         imx_gpio_mode(PB9_PF_SD_DAT1);
 978         imx_gpio_mode(PB10_PF_SD_DAT2);
 979         /* Configured as GPIO with pull-up to ensure right MCC card mode */
 980         /* Switched to PB11_PF_SD_DAT3 if 4 bit bus is configured */
 981         imx_gpio_mode(GPIO_PORTB | GPIO_IN | GPIO_PUEN | 11);
 982         /* imx_gpio_mode(PB11_PF_SD_DAT3); */
 983         imx_gpio_mode(PB12_PF_SD_CLK);
 984         imx_gpio_mode(PB13_PF_SD_CMD);
 985
 986         imxmci_softreset();
 987
 988         if ( MMC_REV_NO != 0x390 ) {
 989                 dev_err(mmc_dev(host->mmc), "wrong rev.no. 0x%08x. aborting.\n",
 990                         MMC_REV_NO);
 991                 goto out;
 992         }
 993
 994         MMC_READ_TO = 0x2db4; /* recommended in data sheet */
 995
 996         host->imask = IMXMCI_INT_MASK_DEFAULT;
 997         MMC_INT_MASK = host->imask;
 998
 999
1000         if(imx_dma_request_by_prio(&host->dma, DRIVER_NAME, DMA_PRIO_LOW)<0){
1001                 dev_err(mmc_dev(host->mmc), "imx_dma_request_by_prio failed\n");
1002                 ret = -EBUSY;
1003                 goto out;
1004         }
1005         host->dma_allocated=1;
1006         imx_dma_setup_handlers(host->dma, imxmci_dma_irq, NULL, host);
1007
1008         tasklet_init(&host->tasklet, imxmci_tasklet_fnc, (unsigned long)host);
1009         host->status_reg=0;
1010         host->pending_events=0;
1011
1012         ret = request_irq(host->irq, imxmci_irq, 0, DRIVER_NAME, host);
1013         if (ret)
1014                 goto out;
1015
1016         host->present = host->pdata->card_present();
1017         init_timer(&host->timer);
1018         host->timer.data = (unsigned long)host;
1019         host->timer.function = imxmci_check_status;
1020         add_timer(&host->timer);
1021         mod_timer(&host->timer, jiffies + (HZ>>1));
1022
1023         platform_set_drvdata(pdev, mmc);
1024
1025         mmc_add_host(mmc);
1026
1027         return 0;
1028
1029 out:
1030         if (host) {
1031                 if(host->dma_allocated){
1032                         imx_dma_free(host->dma);
1033                         host->dma_allocated=0;
1034                 }
1035         }
1036         if (mmc)
1037                 mmc_free_host(mmc);
1038         release_resource(r);
1039         return ret;
1040 }
1041
1042 static int imxmci_remove(struct platform_device *pdev)
1043 {
1044         struct mmc_host *mmc = platform_get_drvdata(pdev);
1045
1046         platform_set_drvdata(pdev, NULL);
1047
1048         if (mmc) {
1049                 struct imxmci_host *host = mmc_priv(mmc);
1050
1051                 tasklet_disable(&host->tasklet);
1052
1053                 del_timer_sync(&host->timer);
1054                 mmc_remove_host(mmc);
1055
1056                 free_irq(host->irq, host);
1057                 if(host->dma_allocated){
1058                         imx_dma_free(host->dma);
1059                         host->dma_allocated=0;
1060                 }
1061
1062                 tasklet_kill(&host->tasklet);
1063
1064                 release_resource(host->res);
1065
1066                 mmc_free_host(mmc);
1067         }
1068         return 0;
1069 }
1070
1071 #ifdef CONFIG_PM
1072 static int imxmci_suspend(struct platform_device *dev, pm_message_t state)
1073 {
1074         struct mmc_host *mmc = platform_get_drvdata(dev);
1075         int ret = 0;
1076
1077         if (mmc)
1078                 ret = mmc_suspend_host(mmc, state);
1079
1080         return ret;
1081 }
1082
1083 static int imxmci_resume(struct platform_device *dev)
1084 {
1085         struct mmc_host *mmc = platform_get_drvdata(dev);
1086         struct imxmci_host *host;
1087         int ret = 0;
1088
1089         if (mmc) {
1090                 host = mmc_priv(mmc);
1091                 if(host)
1092                         set_bit(IMXMCI_PEND_SET_INIT_b, &host->pending_events);
1093                 ret = mmc_resume_host(mmc);
1094         }
1095
1096         return ret;
1097 }
1098 #else
1099 #define imxmci_suspend  NULL
1100 #define imxmci_resume   NULL
1101 #endif /* CONFIG_PM */
1102
1103 static struct platform_driver imxmci_driver = {
1104         .probe          = imxmci_probe,
1105         .remove         = imxmci_remove,
1106         .suspend        = imxmci_suspend,
1107         .resume         = imxmci_resume,
1108         .driver         = {
1109                 .name           = DRIVER_NAME,
1110         }
1111 };
1112
1113 static int __init imxmci_init(void)
1114 {
1115         return platform_driver_register(&imxmci_driver);
1116 }
1117
1118 static void __exit imxmci_exit(void)
1119 {
1120         platform_driver_unregister(&imxmci_driver);
1121 }
1122
1123 module_init(imxmci_init);
1124 module_exit(imxmci_exit);
1125
1126 MODULE_DESCRIPTION("i.MX Multimedia Card Interface Driver");
1127 MODULE_AUTHOR("Sascha Hauer, Pengutronix");
1128 MODULE_LICENSE("GPL");