mmc: at91_mci: fix hanging and rework to match flowcharts

Fixes hanging using multi block operations (seen during CMD25).
Follows closely the datasheet flowcharts.

This piece of code handles better big file writing. I had to take care
of the notbusy signal during write (at91_mci_handle_cmdrdy function) and
to rearrange the AT91_MCI_ENDRX and AT91_MCI_RXBUFF flag usage.

Signed-off-by: Nicolas Ferre <nicolas.ferre@rfo.atmel.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>

1 files changed, 108 insertions, 91 deletions

diff --git a/drivers/mmc/host/at91_mci.c b/drivers/mmc/host/at91_mci.c
index 647f29473cf9..28c881895ab7 100644
--- a/drivers/mmc/host/at91_mci.c
+++ b/drivers/mmc/host/at91_mci.c
@@ -78,8 +78,6 @@
 
 #define DRIVER_NAME "at91_mci"
 
-#undef  SUPPORT_4WIRE
-
 #define FL_SENT_COMMAND (1 << 0)
 #define FL_SENT_STOP    (1 << 1)
 
@@ -268,8 +266,6 @@ static void at91_mci_post_dma_read(struct at91mci_host *host)
         }
 
         while (host->in_use_index < host->transfer_index) {
-                unsigned int *buffer;
-
                 struct scatterlist *sg;
 
                 pr_debug("finishing index %d\n", host->in_use_index);
@@ -280,20 +276,22 @@ static void at91_mci_post_dma_read(struct at91mci_host *host)
 
                 dma_unmap_page(NULL, sg->dma_address, sg->length, DMA_FROM_DEVICE);
 
-                /* Swap the contents of the buffer */
-                buffer = kmap_atomic(sg->page, KM_BIO_SRC_IRQ) + sg->offset;
-                pr_debug("buffer = %p, length = %d\n", buffer, sg->length);
-
                 data->bytes_xfered += sg->length;
 
                 if (cpu_is_at91rm9200()) {      /* AT91RM9200 errata */
+                        unsigned int *buffer;
                         int index;
 
+                        /* Swap the contents of the buffer */
+                        buffer = kmap_atomic(sg->page, KM_BIO_SRC_IRQ) + sg->offset;
+                        pr_debug("buffer = %p, length = %d\n", buffer, sg->length);
+
                         for (index = 0; index < (sg->length / 4); index++)
                                 buffer[index] = swab32(buffer[index]);
+
+                        kunmap_atomic(buffer, KM_BIO_SRC_IRQ);
                 }
 
-                kunmap_atomic(buffer, KM_BIO_SRC_IRQ);
                 flush_dcache_page(sg->page);
         }
 
@@ -301,8 +299,8 @@ static void at91_mci_post_dma_read(struct at91mci_host *host)
         if (host->transfer_index < data->sg_len)
                 at91_mci_pre_dma_read(host);
         else {
+                at91_mci_write(host, AT91_MCI_IDR, AT91_MCI_ENDRX);
                 at91_mci_write(host, AT91_MCI_IER, AT91_MCI_RXBUFF);
-                at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
         }
 
         pr_debug("post dma read done\n");
@@ -323,7 +321,6 @@ static void at91_mci_handle_transmitted(struct at91mci_host *host)
 
         /* Now wait for cmd ready */
         at91_mci_write(host, AT91_MCI_IDR, AT91_MCI_TXBUFE);
-        at91_mci_write(host, AT91_MCI_IER, AT91_MCI_NOTBUSY);
 
         cmd = host->cmd;
         if (!cmd) return;
@@ -331,18 +328,53 @@ static void at91_mci_handle_transmitted(struct at91mci_host *host)
         data = cmd->data;
         if (!data) return;
 
+        if (cmd->data->flags & MMC_DATA_MULTI) {
+                pr_debug("multiple write : wait for BLKE...\n");
+                at91_mci_write(host, AT91_MCI_IER, AT91_MCI_BLKE);
+        } else
+                at91_mci_write(host, AT91_MCI_IER, AT91_MCI_NOTBUSY);
+
         data->bytes_xfered = host->total_length;
 }
 
+/*Handle after command sent ready*/
+static int at91_mci_handle_cmdrdy(struct at91mci_host *host)
+{
+        if (!host->cmd)
+                return 1;
+        else if (!host->cmd->data) {
+                if (host->flags & FL_SENT_STOP) {
+                        /*After multi block write, we must wait for NOTBUSY*/
+                        at91_mci_write(host, AT91_MCI_IER, AT91_MCI_NOTBUSY);
+                } else return 1;
+        } else if (host->cmd->data->flags & MMC_DATA_WRITE) {
+                /*After sendding multi-block-write command, start DMA transfer*/
+                at91_mci_write(host, AT91_MCI_IER, AT91_MCI_TXBUFE);
+                at91_mci_write(host, AT91_MCI_IER, AT91_MCI_BLKE);
+                at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN);
+        }
+
+        /* command not completed, have to wait */
+        return 0;
+}
+
+
 /*
  * Enable the controller
  */
 static void at91_mci_enable(struct at91mci_host *host)
 {
+        unsigned int mr;
+
         at91_mci_write(host, AT91_MCI_CR, AT91_MCI_MCIEN);
         at91_mci_write(host, AT91_MCI_IDR, 0xffffffff);
         at91_mci_write(host, AT91_MCI_DTOR, AT91_MCI_DTOMUL_1M | AT91_MCI_DTOCYC);
-        at91_mci_write(host, AT91_MCI_MR, AT91_MCI_PDCMODE | 0x34a);
+        mr = AT91_MCI_PDCMODE | 0x34a;
+
+        if (cpu_is_at91sam9260() || cpu_is_at91sam9263())
+                mr |= AT91_MCI_RDPROOF | AT91_MCI_WRPROOF;
+
+        at91_mci_write(host, AT91_MCI_MR, mr);
 
         /* use Slot A or B (only one at same time) */
         at91_mci_write(host, AT91_MCI_SDCR, host->board->slot_b);
@@ -358,9 +390,8 @@ static void at91_mci_disable(struct at91mci_host *host)
 
 /*
  * Send a command
- * return the interrupts to enable
  */
-static unsigned int at91_mci_send_command(struct at91mci_host *host, struct mmc_command *cmd)
+static void at91_mci_send_command(struct at91mci_host *host, struct mmc_command *cmd)
 {
         unsigned int cmdr, mr;
         unsigned int block_length;
@@ -371,8 +402,7 @@ static unsigned int at91_mci_send_command(struct at91mci_host *host, struct mmc_
 
         host->cmd = cmd;
 
-        /* Not sure if this is needed */
-#if 0
+        /* Needed for leaving busy state before CMD1 */
         if ((at91_mci_read(host, AT91_MCI_SR) & AT91_MCI_RTOE) && (cmd->opcode == 1)) {
                 pr_debug("Clearing timeout\n");
                 at91_mci_write(host, AT91_MCI_ARGR, 0);
@@ -382,7 +412,7 @@ static unsigned int at91_mci_send_command(struct at91mci_host *host, struct mmc_
                         pr_debug("Clearing: SR = %08X\n", at91_mci_read(host, AT91_MCI_SR));
                 }
         }
-#endif
+
         cmdr = cmd->opcode;
 
         if (mmc_resp_type(cmd) == MMC_RSP_NONE)
@@ -439,50 +469,48 @@ static unsigned int at91_mci_send_command(struct at91mci_host *host, struct mmc_
                 at91_mci_write(host, ATMEL_PDC_TCR, 0);
                 at91_mci_write(host, ATMEL_PDC_TNPR, 0);
                 at91_mci_write(host, ATMEL_PDC_TNCR, 0);
+                ier = AT91_MCI_CMDRDY;
+        } else {
+                /* zero block length and PDC mode */
+                mr = at91_mci_read(host, AT91_MCI_MR) & 0x7fff;
+                at91_mci_write(host, AT91_MCI_MR, mr | (block_length << 16) | AT91_MCI_PDCMODE);
 
-                at91_mci_write(host, AT91_MCI_ARGR, cmd->arg);
-                at91_mci_write(host, AT91_MCI_CMDR, cmdr);
-                return AT91_MCI_CMDRDY;
-        }
-
-        mr = at91_mci_read(host, AT91_MCI_MR) & 0x7fff; /* zero block length and PDC mode */
-        at91_mci_write(host, AT91_MCI_MR, mr | (block_length << 16) | AT91_MCI_PDCMODE);
-
-        /*
-         * Disable the PDC controller
-         */
-        at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
-
-        if (cmdr & AT91_MCI_TRCMD_START) {
-                data->bytes_xfered = 0;
-                host->transfer_index = 0;
-                host->in_use_index = 0;
-                if (cmdr & AT91_MCI_TRDIR) {
-                        /*
-                         * Handle a read
-                         */
-                        host->buffer = NULL;
-                        host->total_length = 0;
-
-                        at91_mci_pre_dma_read(host);
-                        ier = AT91_MCI_ENDRX /* | AT91_MCI_RXBUFF */;
-                }
-                else {
-                        /*
-                         * Handle a write
-                         */
-                        host->total_length = block_length * blocks;
-                        host->buffer = dma_alloc_coherent(NULL,
-                                                  host->total_length,
-                                                  &host->physical_address, GFP_KERNEL);
-
-                        at91_mci_sg_to_dma(host, data);
-
-                        pr_debug("Transmitting %d bytes\n", host->total_length);
+                /*
+                 * Disable the PDC controller
+                 */
+                at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
 
-                        at91_mci_write(host, ATMEL_PDC_TPR, host->physical_address);
-                        at91_mci_write(host, ATMEL_PDC_TCR, host->total_length / 4);
-                        ier = AT91_MCI_TXBUFE;
+                if (cmdr & AT91_MCI_TRCMD_START) {
+                        data->bytes_xfered = 0;
+                        host->transfer_index = 0;
+                        host->in_use_index = 0;
+                        if (cmdr & AT91_MCI_TRDIR) {
+                                /*
+                                 * Handle a read
+                                 */
+                                host->buffer = NULL;
+                                host->total_length = 0;
+
+                                at91_mci_pre_dma_read(host);
+                                ier = AT91_MCI_ENDRX /* | AT91_MCI_RXBUFF */;
+                        }
+                        else {
+                                /*
+                                 * Handle a write
+                                 */
+                                host->total_length = block_length * blocks;
+                                host->buffer = dma_alloc_coherent(NULL,
+                                                host->total_length,
+                                                &host->physical_address, GFP_KERNEL);
+
+                                at91_mci_sg_to_dma(host, data);
+
+                                pr_debug("Transmitting %d bytes\n", host->total_length);
+
+                                at91_mci_write(host, ATMEL_PDC_TPR, host->physical_address);
+                                at91_mci_write(host, ATMEL_PDC_TCR, host->total_length / 4);
+                                ier = AT91_MCI_CMDRDY;
+                        }
                 }
         }
 
@@ -497,24 +525,9 @@ static unsigned int at91_mci_send_command(struct at91mci_host *host, struct mmc_
         if (cmdr & AT91_MCI_TRCMD_START) {
                 if (cmdr & AT91_MCI_TRDIR)
                         at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTEN);
-                else
-                        at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN);
         }
-        return ier;
-}
 
-/*
- * Wait for a command to complete
- */
-static void at91_mci_process_command(struct at91mci_host *host, struct mmc_command *cmd)
-{
-        unsigned int ier;
-
-        ier = at91_mci_send_command(host, cmd);
-
-        pr_debug("setting ier to %08X\n", ier);
-
-        /* Stop on errors or the required value */
+        /* Enable selected interrupts */
         at91_mci_write(host, AT91_MCI_IER, AT91_MCI_ERRORS | ier);
 }
 
@@ -525,11 +538,11 @@ static void at91_mci_process_next(struct at91mci_host *host)
 {
         if (!(host->flags & FL_SENT_COMMAND)) {
                 host->flags |= FL_SENT_COMMAND;
-                at91_mci_process_command(host, host->request->cmd);
+                at91_mci_send_command(host, host->request->cmd);
         }
         else if ((!(host->flags & FL_SENT_STOP)) && host->request->stop) {
                 host->flags |= FL_SENT_STOP;
-                at91_mci_process_command(host, host->request->stop);
+                at91_mci_send_command(host, host->request->stop);
         }
         else
                 mmc_request_done(host->mmc, host->request);
@@ -698,29 +711,33 @@ static irqreturn_t at91_mci_irq(int irq, void *devid)
                         at91_mci_handle_transmitted(host);
                 }
 
+                if (int_status & AT91_MCI_ENDRX) {
+                        pr_debug("ENDRX\n");
+                        at91_mci_post_dma_read(host);
+                }
+
                 if (int_status & AT91_MCI_RXBUFF) {
                         pr_debug("RX buffer full\n");
-                        at91_mci_write(host, AT91_MCI_IER, AT91_MCI_CMDRDY);
+                        at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
+                        at91_mci_write(host, AT91_MCI_IDR, AT91_MCI_RXBUFF | AT91_MCI_ENDRX);
+                        completed = 1;
                 }
 
                 if (int_status & AT91_MCI_ENDTX)
                         pr_debug("Transmit has ended\n");
 
-                if (int_status & AT91_MCI_ENDRX) {
-                        pr_debug("Receive has ended\n");
-                        at91_mci_post_dma_read(host);
-                }
-
                 if (int_status & AT91_MCI_NOTBUSY) {
                         pr_debug("Card is ready\n");
-                        at91_mci_write(host, AT91_MCI_IER, AT91_MCI_CMDRDY);
+                        completed = 1;
                 }
 
                 if (int_status & AT91_MCI_DTIP)
                         pr_debug("Data transfer in progress\n");
 
-                if (int_status & AT91_MCI_BLKE)
+                if (int_status & AT91_MCI_BLKE) {
                         pr_debug("Block transfer has ended\n");
+                        completed = 1;
+                }
 
                 if (int_status & AT91_MCI_TXRDY)
                         pr_debug("Ready to transmit\n");
@@ -730,7 +747,7 @@ static irqreturn_t at91_mci_irq(int irq, void *devid)
 
                 if (int_status & AT91_MCI_CMDRDY) {
                         pr_debug("Command ready\n");
-                        completed = 1;
+                        completed = at91_mci_handle_cmdrdy(host);
                 }
         }
 
@@ -830,11 +847,11 @@ static int __init at91_mci_probe(struct platform_device *pdev)
         host->bus_mode = 0;
         host->board = pdev->dev.platform_data;
         if (host->board->wire4) {
-#ifdef SUPPORT_4WIRE
-                mmc->caps |= MMC_CAP_4_BIT_DATA;
-#else
-                printk("AT91 MMC: 4 wire bus mode not supported by this driver - using 1 wire\n");
-#endif
+                if (cpu_is_at91sam9260() || cpu_is_at91sam9263())
+                        mmc->caps |= MMC_CAP_4_BIT_DATA;
+                else
+                        printk("AT91 MMC: 4 wire bus mode not supported"
+                                " - using 1 wire\n");
         }
 
         /*