1 files changed, 78 insertions, 14 deletions

diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index e94476beca18..6f56ef025ab5 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -91,6 +91,11 @@ struct atmel_mci_dma {
  * @regs: Pointer to MMIO registers.
  * @sg: Scatterlist entry currently being processed by PIO or PDC code.
  * @pio_offset: Offset into the current scatterlist entry.
+ * @buffer: Buffer used if we don't have the r/w proof capability. We
+ *      don't have the time to switch pdc buffers so we have to use only
+ *      one buffer for the full transaction.
+ * @buf_size: size of the buffer.
+ * @phys_buf_addr: buffer address needed for pdc.
  * @cur_slot: The slot which is currently using the controller.
  * @mrq: The request currently being processed on @cur_slot,
  *      or NULL if the controller is idle.
@@ -166,6 +171,9 @@ struct atmel_mci {
 
         struct scatterlist      *sg;
         unsigned int            pio_offset;
+        unsigned int            *buffer;
+        unsigned int            buf_size;
+        dma_addr_t              buf_phys_addr;
 
         struct atmel_mci_slot   *cur_slot;
         struct mmc_request      *mrq;
@@ -480,6 +488,11 @@ err:
         dev_err(&mmc->class_dev, "failed to initialize debugfs for slot\n");
 }
 
+static inline unsigned int atmci_get_version(struct atmel_mci *host)
+{
+        return atmci_readl(host, ATMCI_VERSION) & 0x00000fff;
+}
+
 static inline unsigned int atmci_ns_to_clocks(struct atmel_mci *host,
                                         unsigned int ns)
 {
@@ -603,6 +616,7 @@ static void atmci_pdc_set_single_buf(struct atmel_mci *host,
         enum atmci_xfer_dir dir, enum atmci_pdc_buf buf_nb)
 {
         u32 pointer_reg, counter_reg;
+        unsigned int buf_size;
 
         if (dir == XFER_RECEIVE) {
                 pointer_reg = ATMEL_PDC_RPR;
@@ -617,8 +631,15 @@ static void atmci_pdc_set_single_buf(struct atmel_mci *host,
                 counter_reg += ATMEL_PDC_SCND_BUF_OFF;
         }
 
-        atmci_writel(host, pointer_reg, sg_dma_address(host->sg));
-        if (host->data_size <= sg_dma_len(host->sg)) {
+        if (!host->caps.has_rwproof) {
+                buf_size = host->buf_size;
+                atmci_writel(host, pointer_reg, host->buf_phys_addr);
+        } else {
+                buf_size = sg_dma_len(host->sg);
+                atmci_writel(host, pointer_reg, sg_dma_address(host->sg));
+        }
+
+        if (host->data_size <= buf_size) {
                 if (host->data_size & 0x3) {
                         /* If size is different from modulo 4, transfer bytes */
                         atmci_writel(host, counter_reg, host->data_size);
@@ -670,7 +691,15 @@ static void atmci_pdc_cleanup(struct atmel_mci *host)
  */
 static void atmci_pdc_complete(struct atmel_mci *host)
 {
+        int transfer_size = host->data->blocks * host->data->blksz;
+
         atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
+
+        if ((!host->caps.has_rwproof)
+            && (host->data->flags & MMC_DATA_READ))
+                sg_copy_from_buffer(host->data->sg, host->data->sg_len,
+                                    host->buffer, transfer_size);
+
         atmci_pdc_cleanup(host);
 
         /*
@@ -818,6 +847,12 @@ atmci_prepare_data_pdc(struct atmel_mci *host, struct mmc_data *data)
         /* Configure PDC */
         host->data_size = data->blocks * data->blksz;
         sg_len = dma_map_sg(&host->pdev->dev, data->sg, data->sg_len, dir);
+
+        if ((!host->caps.has_rwproof)
+            && (host->data->flags & MMC_DATA_WRITE))
+                sg_copy_to_buffer(host->data->sg, host->data->sg_len,
+                                  host->buffer, host->data_size);
+
         if (host->data_size)
                 atmci_pdc_set_both_buf(host,
                         ((dir == DMA_FROM_DEVICE) ? XFER_RECEIVE : XFER_TRANSMIT));
@@ -1877,13 +1912,26 @@ static int __init atmci_init_slot(struct atmel_mci *host,
                 mmc->caps |= MMC_CAP_SDIO_IRQ;
         if (host->caps.has_highspeed)
                 mmc->caps |= MMC_CAP_SD_HIGHSPEED;
-        if (slot_data->bus_width >= 4)
+        /*
+         * Without the read/write proof capability, it is strongly suggested to
+         * use only one bit for data to prevent fifo underruns and overruns
+         * which will corrupt data.
+         */
+        if ((slot_data->bus_width >= 4) && host->caps.has_rwproof)
                 mmc->caps |= MMC_CAP_4_BIT_DATA;
 
-        mmc->max_segs = 64;
-        mmc->max_req_size = 32768 * 512;
-        mmc->max_blk_size = 32768;
-        mmc->max_blk_count = 512;
+        if (atmci_get_version(host) < 0x200) {
+                mmc->max_segs = 256;
+                mmc->max_blk_size = 4095;
+                mmc->max_blk_count = 256;
+                mmc->max_req_size = mmc->max_blk_size * mmc->max_blk_count;
+                mmc->max_seg_size = mmc->max_blk_size * mmc->max_segs;
+        } else {
+                mmc->max_segs = 64;
+                mmc->max_req_size = 32768 * 512;
+                mmc->max_blk_size = 32768;
+                mmc->max_blk_count = 512;
+        }
 
         /* Assume card is present initially */
         set_bit(ATMCI_CARD_PRESENT, &slot->flags);
@@ -2007,11 +2055,6 @@ static bool atmci_configure_dma(struct atmel_mci *host)
         }
 }
 
-static inline unsigned int atmci_get_version(struct atmel_mci *host)
-{
-        return atmci_readl(host, ATMCI_VERSION) & 0x00000fff;
-}
-
 /*
  * HSMCI (High Speed MCI) module is not fully compatible with MCI module.
  * HSMCI provides DMA support and a new config register but no more supports
@@ -2138,14 +2181,20 @@ static int __init atmci_probe(struct platform_device *pdev)
         if (pdata->slot[0].bus_width) {
                 ret = atmci_init_slot(host, &pdata->slot[0],
                                 0, ATMCI_SDCSEL_SLOT_A, ATMCI_SDIOIRQA);
-                if (!ret)
+                if (!ret) {
                         nr_slots++;
+                        host->buf_size = host->slot[0]->mmc->max_req_size;
+                }
         }
         if (pdata->slot[1].bus_width) {
                 ret = atmci_init_slot(host, &pdata->slot[1],
                                 1, ATMCI_SDCSEL_SLOT_B, ATMCI_SDIOIRQB);
-                if (!ret)
+                if (!ret) {
                         nr_slots++;
+                        if (host->slot[1]->mmc->max_req_size > host->buf_size)
+                                host->buf_size =
+                                        host->slot[1]->mmc->max_req_size;
+                }
         }
 
         if (!nr_slots) {
@@ -2153,6 +2202,17 @@ static int __init atmci_probe(struct platform_device *pdev)
                 goto err_init_slot;
         }
 
+        if (!host->caps.has_rwproof) {
+                host->buffer = dma_alloc_coherent(&pdev->dev, host->buf_size,
+                                                  &host->buf_phys_addr,
+                                                  GFP_KERNEL);
+                if (!host->buffer) {
+                        ret = -ENOMEM;
+                        dev_err(&pdev->dev, "buffer allocation failed\n");
+                        goto err_init_slot;
+                }
+        }
+
         dev_info(&pdev->dev,
                         "Atmel MCI controller at 0x%08lx irq %d, %u slots\n",
                         host->mapbase, irq, nr_slots);
@@ -2179,6 +2239,10 @@ static int __exit atmci_remove(struct platform_device *pdev)
 
         platform_set_drvdata(pdev, NULL);
 
+        if (host->buffer)
+                dma_free_coherent(&pdev->dev, host->buf_size,
+                                  host->buffer, host->buf_phys_addr);
+
         for (i = 0; i < ATMCI_MAX_NR_SLOTS; i++) {
                 if (host->slot[i])
                         atmci_cleanup_slot(host->slot[i], i);