Merge with /home/tmlind/src/kernel/linux-2.6

[linux-2.6-omap-h63xx.git] / drivers / mmc / imxmmc.c

diff --git a/drivers/mmc/imxmmc.c b/drivers/mmc/imxmmc.c
index ffb7f55d34676eb3a96b6a727d4bfabf8e5d6390..7ca9e95bdf89b89c03237b3f4e1eb9f6ffa2124f 100644 (file)
--- a/drivers/mmc/imxmmc.c
+++ b/drivers/mmc/imxmmc.c
@@ -25,7 +25,6 @@
  *             deficiencies
  *
  */
-#include <linux/config.h>
 
 #ifdef CONFIG_MMC_DEBUG
 #define DEBUG
@@ -102,6 +101,7 @@ struct imxmci_host {
 #define IMXMCI_PEND_CPU_DATA_b 5
 #define IMXMCI_PEND_CARD_XCHG_b        6
 #define IMXMCI_PEND_SET_INIT_b 7
+#define IMXMCI_PEND_STARTED_b  8
 
 #define IMXMCI_PEND_IRQ_m      (1 << IMXMCI_PEND_IRQ_b)
 #define IMXMCI_PEND_DMA_END_m  (1 << IMXMCI_PEND_DMA_END_b)
@@ -111,6 +111,7 @@ struct imxmci_host {
 #define IMXMCI_PEND_CPU_DATA_m (1 << IMXMCI_PEND_CPU_DATA_b)
 #define IMXMCI_PEND_CARD_XCHG_m        (1 << IMXMCI_PEND_CARD_XCHG_b)
 #define IMXMCI_PEND_SET_INIT_m (1 << IMXMCI_PEND_SET_INIT_b)
+#define IMXMCI_PEND_STARTED_m  (1 << IMXMCI_PEND_STARTED_b)
 
 static void imxmci_stop_clock(struct imxmci_host *host)
 {
@@ -131,23 +132,52 @@ static void imxmci_stop_clock(struct imxmci_host *host)
        dev_dbg(mmc_dev(host->mmc), "imxmci_stop_clock blocked, no luck\n");
 }
 
-static void imxmci_start_clock(struct imxmci_host *host)
+static int imxmci_start_clock(struct imxmci_host *host)
 {
-       int i = 0;
+       unsigned int trials = 0;
+       unsigned int delay_limit = 128;
+       unsigned long flags;
+
        MMC_STR_STP_CLK &= ~STR_STP_CLK_STOP_CLK;
-       while(i < 0x1000) {
-               if(!(i & 0x7f))
-                       MMC_STR_STP_CLK |= STR_STP_CLK_START_CLK;
 
-               if(MMC_STATUS & STATUS_CARD_BUS_CLK_RUN) {
-                       /* Check twice before cut */
+       clear_bit(IMXMCI_PEND_STARTED_b, &host->pending_events);
+
+       /*
+        * Command start of the clock, this usually succeeds in less
+        * then 6 delay loops, but during card detection (low clockrate)
+        * it takes up to 5000 delay loops and sometimes fails for the first time
+        */
+       MMC_STR_STP_CLK |= STR_STP_CLK_START_CLK;
+
+       do {
+               unsigned int delay = delay_limit;
+
+               while(delay--){
                        if(MMC_STATUS & STATUS_CARD_BUS_CLK_RUN)
-                               return;
+                               /* Check twice before cut */
+                               if(MMC_STATUS & STATUS_CARD_BUS_CLK_RUN)
+                                       return 0;
+
+                       if(test_bit(IMXMCI_PEND_STARTED_b, &host->pending_events))
+                               return 0;
                }
 
-               i++;
-       }
-       dev_dbg(mmc_dev(host->mmc), "imxmci_start_clock blocked, no luck\n");
+               local_irq_save(flags);
+               /*
+                * Ensure, that request is not doubled under all possible circumstances.
+                * It is possible, that cock running state is missed, because some other
+                * IRQ or schedule delays this function execution and the clocks has
+                * been already stopped by other means (response processing, SDHC HW)
+                */
+               if(!test_bit(IMXMCI_PEND_STARTED_b, &host->pending_events))
+                       MMC_STR_STP_CLK |= STR_STP_CLK_START_CLK;
+               local_irq_restore(flags);
+
+       } while(++trials<256);
+
+       dev_err(mmc_dev(host->mmc), "imxmci_start_clock blocked, no luck\n");
+
+       return -1;
 }
 
 static void imxmci_softreset(void)
@@ -187,15 +217,17 @@ static int imxmci_busy_wait_for_status(struct imxmci_host *host,
        if(!loops)
                return 0;
 
-       dev_info(mmc_dev(host->mmc), "busy wait for %d usec in %s, STATUS = 0x%x (0x%x)\n",
-               loops, where, *pstat, stat_mask);
+       /* The busy-wait is expected there for clock <8MHz due to SDHC hardware flaws */
+       if(!(stat_mask & STATUS_END_CMD_RESP) || (host->mmc->ios.clock>=8000000))
+               dev_info(mmc_dev(host->mmc), "busy wait for %d usec in %s, STATUS = 0x%x (0x%x)\n",
+                       loops, where, *pstat, stat_mask);
        return loops;
 }
 
 static void imxmci_setup_data(struct imxmci_host *host, struct mmc_data *data)
 {
        unsigned int nob = data->blocks;
-       unsigned int blksz = 1 << data->blksz_bits;
+       unsigned int blksz = data->blksz;
        unsigned int datasz = nob * blksz;
        int i;
 
@@ -302,6 +334,9 @@ static void imxmci_start_cmd(struct imxmci_host *host, struct mmc_command *cmd,
        WARN_ON(host->cmd != NULL);
        host->cmd = cmd;
 
+       /* Ensure, that clock are stopped else command programming and start fails */
+       imxmci_stop_clock(host);
+
        if (cmd->flags & MMC_RSP_BUSY)
                cmdat |= CMD_DAT_CONT_BUSY;
 
@@ -498,7 +533,7 @@ static int imxmci_data_done(struct imxmci_host *host, unsigned int stat)
 
        data_error = imxmci_finish_data(host, stat);
 
-       if (host->req->stop && (data_error == MMC_ERR_NONE)) {
+       if (host->req->stop) {
                imxmci_stop_clock(host);
                imxmci_start_cmd(host, host->req->stop, 0);
        } else {
@@ -522,7 +557,7 @@ static int imxmci_cpu_driven_data(struct imxmci_host *host, unsigned int *pstat)
        int trans_done = 0;
        unsigned int stat = *pstat;
 
-       if(host->actual_bus_width == MMC_BUS_WIDTH_4)
+       if(host->actual_bus_width != MMC_BUS_WIDTH_4)
                burst_len = 16;
        else
                burst_len = 64;
@@ -560,8 +595,7 @@ static int imxmci_cpu_driven_data(struct imxmci_host *host, unsigned int *pstat)
                        stat = MMC_STATUS;
 
                        /* Flush extra bytes from FIFO */
-                       while(flush_len >= 2){
-                               flush_len -= 2;
+                       while(flush_len && !(stat & STATUS_DATA_TRANS_DONE)){
                                i = MMC_BUFFER_ACCESS;
                                stat = MMC_STATUS;
                                stat &= ~STATUS_CRC_READ_ERR; /* Stupid but required there */
@@ -622,6 +656,7 @@ static irqreturn_t imxmci_irq(int irq, void *devid, struct pt_regs *regs)
        atomic_set(&host->stuck_timeout, 0);
        host->status_reg = stat;
        set_bit(IMXMCI_PEND_IRQ_b, &host->pending_events);
+       set_bit(IMXMCI_PEND_STARTED_b, &host->pending_events);
        tasklet_schedule(&host->tasklet);
 
        return IRQ_RETVAL(handled);;
@@ -714,10 +749,6 @@ static void imxmci_tasklet_fnc(unsigned long data)
                        data_dir_mask = STATUS_DATA_TRANS_DONE;
                }
 
-               imxmci_busy_wait_for_status(host, &stat,
-                               data_dir_mask,
-                               50, "imxmci_tasklet_fnc data");
-
                if(stat & data_dir_mask) {
                        clear_bit(IMXMCI_PEND_DMA_END_b, &host->pending_events);
                        imxmci_data_done(host, stat);
@@ -775,10 +806,6 @@ static void imxmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
        struct imxmci_host *host = mmc_priv(mmc);
        int prescaler;
 
-       dev_dbg(mmc_dev(host->mmc), "clock %u power %u vdd %u width %u\n",
-               ios->clock, ios->power_mode, ios->vdd,
-               (ios->bus_width==MMC_BUS_WIDTH_4)?4:1);
-
        if( ios->bus_width==MMC_BUS_WIDTH_4 ) {
                host->actual_bus_width = MMC_BUS_WIDTH_4;
                imx_gpio_mode(PB11_PF_SD_DAT3);
@@ -837,7 +864,11 @@ static void imxmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 
                imxmci_stop_clock(host);
                MMC_CLK_RATE = (prescaler<<3) | clk;
-               imxmci_start_clock(host);
+               /*
+                * Under my understanding, clock should not be started there, because it would
+                * initiate SDHC sequencer and send last or random command into card
+                */
+               /*imxmci_start_clock(host);*/
 
                dev_dbg(mmc_dev(host->mmc), "MMC_CLK_RATE: 0x%08x\n", MMC_CLK_RATE);
        } else {