mmc: at91_mci: fix hanging and rework to match flowcharts
authorNicolas Ferre <nicolas.ferre@rfo.atmel.com>
Mon, 9 Jul 2007 12:58:16 +0000 (14:58 +0200)
committerPierre Ossman <drzeus@drzeus.cx>
Mon, 9 Jul 2007 19:29:07 +0000 (21:29 +0200)
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>
drivers/mmc/host/at91_mci.c

index 647f29473cf92391b0b43800aa4a05bac1bcc023..28c881895ab79c42a154481644cae2366d5bd47b 100644 (file)
@@ -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");
        }
 
        /*