mmc: atmel-mci: add pdc support and runtime capabilities detection

Add pdc support for atmel-mci. It makes at91-mci driver useless because it
was only used for the old atmel MCI core which has pdc but no dma support.
To allow removing at91-mci, the capabilities of the MCI core are detected
at runtime -- then the driver will use pio, pdc or dma transfers.
Warning: at91rm9200 is not supported, to support it we need to use swab32
on data but I have no board to test it.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

1 files changed, 409 insertions, 118 deletions

diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index 87eeccc6d9a4..57596782061b 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -30,6 +30,7 @@
 
 #include <mach/atmel-mci.h>
 #include <linux/atmel-mci.h>
+#include <linux/atmel_pdc.h>
 
 #include <asm/io.h>
 #include <asm/unaligned.h>
@@ -58,18 +59,35 @@ enum atmel_mci_state {
         STATE_DATA_ERROR,
 };
 
+enum atmci_xfer_dir {
+        XFER_RECEIVE = 0,
+        XFER_TRANSMIT,
+};
+
+enum atmci_pdc_buf {
+        PDC_FIRST_BUF = 0,
+        PDC_SECOND_BUF,
+};
+
+struct atmel_mci_caps {
+        bool    has_dma;
+        bool    has_pdc;
+        bool    has_cfg_reg;
+        bool    has_cstor_reg;
+        bool    has_highspeed;
+        bool    has_rwproof;
+};
+
 struct atmel_mci_dma {
-#ifdef CONFIG_MMC_ATMELMCI_DMA
         struct dma_chan                 *chan;
         struct dma_async_tx_descriptor  *data_desc;
-#endif
 };
 
 /**
  * struct atmel_mci - MMC controller state shared between all slots
  * @lock: Spinlock protecting the queue and associated data.
  * @regs: Pointer to MMIO registers.
- * @sg: Scatterlist entry currently being processed by PIO code, if any.
+ * @sg: Scatterlist entry currently being processed by PIO or PDC code.
  * @pio_offset: Offset into the current scatterlist entry.
  * @cur_slot: The slot which is currently using the controller.
  * @mrq: The request currently being processed on @cur_slot,
@@ -77,6 +95,7 @@ struct atmel_mci_dma {
  * @cmd: The command currently being sent to the card, or NULL.
  * @data: The data currently being transferred, or NULL if no data
  *      transfer is in progress.
+ * @data_size: just data->blocks * data->blksz.
  * @dma: DMA client state.
  * @data_chan: DMA channel being used for the current data transfer.
  * @cmd_status: Snapshot of SR taken upon completion of the current
@@ -103,6 +122,13 @@ struct atmel_mci_dma {
  * @mck: The peripheral bus clock hooked up to the MMC controller.
  * @pdev: Platform device associated with the MMC controller.
  * @slot: Slots sharing this MMC controller.
+ * @caps: MCI capabilities depending on MCI version.
+ * @prepare_data: function to setup MCI before data transfer which
+ * depends on MCI capabilities.
+ * @submit_data: function to start data transfer which depends on MCI
+ * capabilities.
+ * @stop_transfer: function to stop data transfer which depends on MCI
+ * capabilities.
  *
  * Locking
  * =======
@@ -143,6 +169,7 @@ struct atmel_mci {
         struct mmc_request      *mrq;
         struct mmc_command      *cmd;
         struct mmc_data         *data;
+        unsigned int            data_size;
 
         struct atmel_mci_dma    dma;
         struct dma_chan         *data_chan;
@@ -167,6 +194,12 @@ struct atmel_mci {
         struct platform_device  *pdev;
 
         struct atmel_mci_slot   *slot[ATMCI_MAX_NR_SLOTS];
+
+        struct atmel_mci_caps   caps;
+
+        u32 (*prepare_data)(struct atmel_mci *host, struct mmc_data *data);
+        void (*submit_data)(struct atmel_mci *host, struct mmc_data *data);
+        void (*stop_transfer)(struct atmel_mci *host);
 };
 
 /**
@@ -220,31 +253,6 @@ struct atmel_mci_slot {
         set_bit(event, &host->pending_events)
 
 /*
- * Enable or disable features/registers based on
- * whether the processor supports them
- */
-static bool atmci_has_rwproof(void)
-{
-        if (cpu_is_at91sam9261() || cpu_is_at91rm9200())
-                return false;
-        else
-                return true;
-}
-
-/*
- * The new MCI2 module isn't 100% compatible with the old MCI module,
- * and it has a few nice features which we want to use...
- */
-static inline bool atmci_is_mci2(void)
-{
-        if (cpu_is_at91sam9g45())
-                return true;
-
-        return false;
-}
-
-
-/*
  * The debugfs stuff below is mostly optimized away when
  * CONFIG_DEBUG_FS is not set.
  */
@@ -379,7 +387,7 @@ static int atmci_regs_show(struct seq_file *s, void *v)
                         buf[ATMCI_BLKR / 4],
                         buf[ATMCI_BLKR / 4] & 0xffff,
                         (buf[ATMCI_BLKR / 4] >> 16) & 0xffff);
-        if (atmci_is_mci2())
+        if (host->caps.has_cstor_reg)
                 seq_printf(s, "CSTOR:\t0x%08x\n", buf[ATMCI_CSTOR / 4]);
 
         /* Don't read RSPR and RDR; it will consume the data there */
@@ -387,7 +395,7 @@ static int atmci_regs_show(struct seq_file *s, void *v)
         atmci_show_status_reg(s, "SR", buf[ATMCI_SR / 4]);
         atmci_show_status_reg(s, "IMR", buf[ATMCI_IMR / 4]);
 
-        if (atmci_is_mci2()) {
+        if (host->caps.has_dma) {
                 u32 val;
 
                 val = buf[ATMCI_DMA / 4];
@@ -396,6 +404,9 @@ static int atmci_regs_show(struct seq_file *s, void *v)
                                 ((val >> 4) & 3) ?
                                         1 << (((val >> 4) & 3) + 1) : 1,
                                 val & ATMCI_DMAEN ? " DMAEN" : "");
+        }
+        if (host->caps.has_cfg_reg) {
+                u32 val;
 
                 val = buf[ATMCI_CFG / 4];
                 seq_printf(s, "CFG:\t0x%08x%s%s%s%s\n",
@@ -574,33 +585,109 @@ static void atmci_send_stop_cmd(struct atmel_mci *host, struct mmc_data *data)
         atmci_writel(host, ATMCI_IER, ATMCI_CMDRDY);
 }
 
-#ifdef CONFIG_MMC_ATMELMCI_DMA
-static void atmci_dma_cleanup(struct atmel_mci *host)
+/*
+ * Configure given PDC buffer taking care of alignement issues.
+ * Update host->data_size and host->sg.
+ */
+static void atmci_pdc_set_single_buf(struct atmel_mci *host,
+        enum atmci_xfer_dir dir, enum atmci_pdc_buf buf_nb)
 {
-        struct mmc_data                 *data = host->data;
+        u32 pointer_reg, counter_reg;
+
+        if (dir == XFER_RECEIVE) {
+                pointer_reg = ATMEL_PDC_RPR;
+                counter_reg = ATMEL_PDC_RCR;
+        } else {
+                pointer_reg = ATMEL_PDC_TPR;
+                counter_reg = ATMEL_PDC_TCR;
+        }
+
+        if (buf_nb == PDC_SECOND_BUF) {
+                pointer_reg += 0x10;
+                counter_reg += 0x10;
+        }
+
+        atmci_writel(host, pointer_reg, sg_dma_address(host->sg));
+        if (host->data_size <= PAGE_SIZE) {
+                if (host->data_size & 0x3) {
+                        /* If size is different from modulo 4, transfer bytes */
+                        atmci_writel(host, counter_reg, host->data_size);
+                        atmci_writel(host, ATMCI_MR, host->mode_reg | ATMCI_MR_PDCFBYTE);
+                } else {
+                        /* Else transfer 32-bits words */
+                        atmci_writel(host, counter_reg, host->data_size / 4);
+                }
+                host->data_size = 0;
+        } else {
+                /* We assume the size of a page is 32-bits aligned */
+                atmci_writel(host, counter_reg, PAGE_SIZE / 4);
+                host->data_size -= PAGE_SIZE;
+                if (host->data_size)
+                        host->sg = sg_next(host->sg);
+        }
+}
+
+/*
+ * Configure PDC buffer according to the data size ie configuring one or two
+ * buffers. Don't use this function if you want to configure only the second
+ * buffer. In this case, use atmci_pdc_set_single_buf.
+ */
+static void atmci_pdc_set_both_buf(struct atmel_mci *host, int dir)
+{
+        atmci_pdc_set_single_buf(host, dir, PDC_FIRST_BUF);
+        if (host->data_size)
+                atmci_pdc_set_single_buf(host, dir, PDC_SECOND_BUF);
+}
+
+/*
+ * Unmap sg lists, called when transfer is finished.
+ */
+static void atmci_pdc_cleanup(struct atmel_mci *host)
+{
+        struct mmc_data         *data = host->data;
 
         if (data)
-                dma_unmap_sg(host->dma.chan->device->dev,
-                             data->sg, data->sg_len,
-                             ((data->flags & MMC_DATA_WRITE)
-                              ? DMA_TO_DEVICE : DMA_FROM_DEVICE));
+                dma_unmap_sg(&host->pdev->dev,
+                                data->sg, data->sg_len,
+                                ((data->flags & MMC_DATA_WRITE)
+                                 ? DMA_TO_DEVICE : DMA_FROM_DEVICE));
 }
 
-static void atmci_stop_dma(struct atmel_mci *host)
+/*
+ * Disable PDC transfers. Update pending flags to EVENT_XFER_COMPLETE after
+ * having received ATMCI_TXBUFE or ATMCI_RXBUFF interrupt. Enable ATMCI_NOTBUSY
+ * interrupt needed for both transfer directions.
+ */
+static void atmci_pdc_complete(struct atmel_mci *host)
 {
-        struct dma_chan *chan = host->data_chan;
+        atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
+        atmci_pdc_cleanup(host);
 
-        if (chan) {
-                dmaengine_terminate_all(chan);
-                atmci_dma_cleanup(host);
-        } else {
-                /* Data transfer was stopped by the interrupt handler */
+        /*
+         * If the card was removed, data will be NULL. No point trying
+         * to send the stop command or waiting for NBUSY in this case.
+         */
+        if (host->data) {
                 atmci_set_pending(host, EVENT_XFER_COMPLETE);
+                tasklet_schedule(&host->tasklet);
                 atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
         }
 }
 
-/* This function is called by the DMA driver from tasklet context. */
+static void atmci_dma_cleanup(struct atmel_mci *host)
+{
+        struct mmc_data                 *data = host->data;
+
+        if (data)
+                dma_unmap_sg(host->dma.chan->device->dev,
+                                data->sg, data->sg_len,
+                                ((data->flags & MMC_DATA_WRITE)
+                                 ? DMA_TO_DEVICE : DMA_FROM_DEVICE));
+}
+
+/*
+ * This function is called by the DMA driver from tasklet context.
+ */
 static void atmci_dma_complete(void *arg)
 {
         struct atmel_mci        *host = arg;
@@ -608,7 +695,7 @@ static void atmci_dma_complete(void *arg)
 
         dev_vdbg(&host->pdev->dev, "DMA complete\n");
 
-        if (atmci_is_mci2())
+        if (host->caps.has_dma)
                 /* Disable DMA hardware handshaking on MCI */
                 atmci_writel(host, ATMCI_DMA, atmci_readl(host, ATMCI_DMA) & ~ATMCI_DMAEN);
 
@@ -646,7 +733,90 @@ static void atmci_dma_complete(void *arg)
         }
 }
 
-static int
+/*
+ * Returns a mask of interrupt flags to be enabled after the whole
+ * request has been prepared.
+ */
+static u32 atmci_prepare_data(struct atmel_mci *host, struct mmc_data *data)
+{
+        u32 iflags;
+
+        data->error = -EINPROGRESS;
+
+        host->sg = data->sg;
+        host->data = data;
+        host->data_chan = NULL;
+
+        iflags = ATMCI_DATA_ERROR_FLAGS;
+
+        /*
+         * Errata: MMC data write operation with less than 12
+         * bytes is impossible.
+         *
+         * Errata: MCI Transmit Data Register (TDR) FIFO
+         * corruption when length is not multiple of 4.
+         */
+        if (data->blocks * data->blksz < 12
+                        || (data->blocks * data->blksz) & 3)
+                host->need_reset = true;
+
+        host->pio_offset = 0;
+        if (data->flags & MMC_DATA_READ)
+                iflags |= ATMCI_RXRDY;
+        else
+                iflags |= ATMCI_TXRDY;
+
+        return iflags;
+}
+
+/*
+ * Set interrupt flags and set block length into the MCI mode register even
+ * if this value is also accessible in the MCI block register. It seems to be
+ * necessary before the High Speed MCI version. It also map sg and configure
+ * PDC registers.
+ */
+static u32
+atmci_prepare_data_pdc(struct atmel_mci *host, struct mmc_data *data)
+{
+        u32 iflags, tmp;
+        unsigned int sg_len;
+        enum dma_data_direction dir;
+
+        data->error = -EINPROGRESS;
+
+        host->data = data;
+        host->sg = data->sg;
+        iflags = ATMCI_DATA_ERROR_FLAGS;
+
+        /* Enable pdc mode */
+        atmci_writel(host, ATMCI_MR, host->mode_reg | ATMCI_MR_PDCMODE);
+
+        if (data->flags & MMC_DATA_READ) {
+                dir = DMA_FROM_DEVICE;
+                iflags |= ATMCI_ENDRX | ATMCI_RXBUFF;
+        } else {
+                dir = DMA_TO_DEVICE;
+                iflags |= ATMCI_ENDTX | ATMCI_TXBUFE;
+        }
+
+        /* Set BLKLEN */
+        tmp = atmci_readl(host, ATMCI_MR);
+        tmp &= 0x0000ffff;
+        tmp |= ATMCI_BLKLEN(data->blksz);
+        atmci_writel(host, ATMCI_MR, tmp);
+
+        /* Configure PDC */
+        host->data_size = data->blocks * data->blksz;
+        sg_len = dma_map_sg(&host->pdev->dev, data->sg, data->sg_len, dir);
+        BUG_ON(sg_len < host->data_size / PAGE_SIZE);
+        if (host->data_size)
+                atmci_pdc_set_both_buf(host,
+                        ((dir == DMA_FROM_DEVICE) ? XFER_RECEIVE : XFER_TRANSMIT));
+
+        return iflags;
+}
+
+static u32
 atmci_prepare_data_dma(struct atmel_mci *host, struct mmc_data *data)
 {
         struct dma_chan                 *chan;
@@ -655,20 +825,29 @@ atmci_prepare_data_dma(struct atmel_mci *host, struct mmc_data *data)
         unsigned int                    i;
         enum dma_data_direction         direction;
         unsigned int                    sglen;
+        u32 iflags;
+
+        data->error = -EINPROGRESS;
+
+        WARN_ON(host->data);
+        host->sg = NULL;
+        host->data = data;
+
+        iflags = ATMCI_DATA_ERROR_FLAGS;
 
         /*
          * We don't do DMA on "complex" transfers, i.e. with
          * non-word-aligned buffers or lengths. Also, we don't bother
          * with all the DMA setup overhead for short transfers.
          */
-        if (data->blocks * data->blksz < ATATMCI_DMA_THRESHOLD)
-                return -EINVAL;
+        if (data->blocks * data->blksz < ATMCI_DMA_THRESHOLD)
+                return atmci_prepare_data(host, data);
         if (data->blksz & 3)
-                return -EINVAL;
+                return atmci_prepare_data(host, data);
 
         for_each_sg(data->sg, sg, data->sg_len, i) {
                 if (sg->offset & 3 || sg->length & 3)
-                        return -EINVAL;
+                        return atmci_prepare_data(host, data);
         }
 
         /* If we don't have a channel, we can't do DMA */
@@ -679,7 +858,7 @@ atmci_prepare_data_dma(struct atmel_mci *host, struct mmc_data *data)
         if (!chan)
                 return -ENODEV;
 
-        if (atmci_is_mci2())
+        if (host->caps.has_dma)
                 atmci_writel(host, ATMCI_DMA, ATMCI_DMA_CHKSIZE(3) | ATMCI_DMAEN);
 
         if (data->flags & MMC_DATA_READ)
@@ -688,7 +867,7 @@ atmci_prepare_data_dma(struct atmel_mci *host, struct mmc_data *data)
                 direction = DMA_TO_DEVICE;
 
         sglen = dma_map_sg(chan->device->dev, data->sg,
-                           data->sg_len, direction);
+                        data->sg_len, direction);
 
         desc = chan->device->device_prep_slave_sg(chan,
                         data->sg, sglen, direction,
@@ -700,13 +879,32 @@ atmci_prepare_data_dma(struct atmel_mci *host, struct mmc_data *data)
         desc->callback = atmci_dma_complete;
         desc->callback_param = host;
 
-        return 0;
+        return iflags;
 unmap_exit:
         dma_unmap_sg(chan->device->dev, data->sg, data->sg_len, direction);
         return -ENOMEM;
 }
 
-static void atmci_submit_data(struct atmel_mci *host)
+static void
+atmci_submit_data(struct atmel_mci *host, struct mmc_data *data)
+{
+        return;
+}
+
+/*
+ * Start PDC according to transfer direction.
+ */
+static void
+atmci_submit_data_pdc(struct atmel_mci *host, struct mmc_data *data)
+{
+        if (data->flags & MMC_DATA_READ)
+                atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTEN);
+        else
+                atmci_writel(host, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN);
+}
+
+static void
+atmci_submit_data_dma(struct atmel_mci *host, struct mmc_data *data)
 {
         struct dma_chan                 *chan = host->data_chan;
         struct dma_async_tx_descriptor  *desc = host->dma.data_desc;
@@ -717,64 +915,39 @@ static void atmci_submit_data(struct atmel_mci *host)
         }
 }
 
-#else /* CONFIG_MMC_ATMELMCI_DMA */
-
-static int atmci_prepare_data_dma(struct atmel_mci *host, struct mmc_data *data)
+static void atmci_stop_transfer(struct atmel_mci *host)
 {
-        return -ENOSYS;
-}
-
-static void atmci_submit_data(struct atmel_mci *host) {}
-
-static void atmci_stop_dma(struct atmel_mci *host)
-{
-        /* Data transfer was stopped by the interrupt handler */
         atmci_set_pending(host, EVENT_XFER_COMPLETE);
         atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
 }
 
-#endif /* CONFIG_MMC_ATMELMCI_DMA */
-
 /*
- * Returns a mask of interrupt flags to be enabled after the whole
- * request has been prepared.
+ * Stop data transfer because error(s) occured.
  */
-static u32 atmci_prepare_data(struct atmel_mci *host, struct mmc_data *data)
+static void atmci_stop_transfer_pdc(struct atmel_mci *host)
 {
-        u32 iflags;
-
-        data->error = -EINPROGRESS;
-
-        WARN_ON(host->data);
-        host->sg = NULL;
-        host->data = data;
-
-        iflags = ATMCI_DATA_ERROR_FLAGS;
-        if (atmci_prepare_data_dma(host, data)) {
-                host->data_chan = NULL;
+        atmci_set_pending(host, EVENT_XFER_COMPLETE);
+        atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
+}
 
-                /*
-                 * Errata: MMC data write operation with less than 12
-                 * bytes is impossible.
-                 *
-                 * Errata: MCI Transmit Data Register (TDR) FIFO
-                 * corruption when length is not multiple of 4.
-                 */
-                if (data->blocks * data->blksz < 12
-                                || (data->blocks * data->blksz) & 3)
-                        host->need_reset = true;
+static void atmci_stop_transfer_dma(struct atmel_mci *host)
+{
+        struct dma_chan *chan = host->data_chan;
 
-                host->sg = data->sg;
-                host->pio_offset = 0;
-                if (data->flags & MMC_DATA_READ)
-                        iflags |= ATMCI_RXRDY;
-                else
-                        iflags |= ATMCI_TXRDY;
+        if (chan) {
+                dmaengine_terminate_all(chan);
+                atmci_dma_cleanup(host);
+        } else {
+                /* Data transfer was stopped by the interrupt handler */
+                atmci_set_pending(host, EVENT_XFER_COMPLETE);
+                atmci_writel(host, ATMCI_IER, ATMCI_NOTBUSY);
         }
-
-        return iflags;
 }
 
+/*
+ * Start a request: prepare data if needed, prepare the command and activate
+ * interrupts.
+ */
 static void atmci_start_request(struct atmel_mci *host,
                 struct atmel_mci_slot *slot)
 {
@@ -796,7 +969,7 @@ static void atmci_start_request(struct atmel_mci *host,
                 atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
                 atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
                 atmci_writel(host, ATMCI_MR, host->mode_reg);
-                if (atmci_is_mci2())
+                if (host->caps.has_cfg_reg)
                         atmci_writel(host, ATMCI_CFG, host->cfg_reg);
                 host->need_reset = false;
         }
@@ -824,7 +997,7 @@ static void atmci_start_request(struct atmel_mci *host,
                 dev_vdbg(&slot->mmc->class_dev, "BLKR=0x%08x\n",
                         ATMCI_BCNT(data->blocks) | ATMCI_BLKLEN(data->blksz));
 
-                iflags |= atmci_prepare_data(host, data);
+                iflags |= host->prepare_data(host, data);
         }
 
         iflags |= ATMCI_CMDRDY;
@@ -833,7 +1006,7 @@ static void atmci_start_request(struct atmel_mci *host,
         atmci_start_command(host, cmd, cmdflags);
 
         if (data)
-                atmci_submit_data(host);
+                host->submit_data(host, data);
 
         if (mrq->stop) {
                 host->stop_cmdr = atmci_prepare_command(slot->mmc, mrq->stop);
@@ -929,7 +1102,7 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
                         clk_enable(host->mck);
                         atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
                         atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
-                        if (atmci_is_mci2())
+                        if (host->caps.has_cfg_reg)
                                 atmci_writel(host, ATMCI_CFG, host->cfg_reg);
                 }
 
@@ -960,10 +1133,10 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
                  * stopping the clock when the FIFO is full/empty.
                  * This state is not expected to last for long.
                  */
-                if (atmci_has_rwproof())
+                if (host->caps.has_rwproof)
                         host->mode_reg |= (ATMCI_MR_WRPROOF | ATMCI_MR_RDPROOF);
 
-                if (atmci_is_mci2()) {
+                if (host->caps.has_cfg_reg) {
                         /* setup High Speed mode in relation with card capacity */
                         if (ios->timing == MMC_TIMING_SD_HS)
                                 host->cfg_reg |= ATMCI_CFG_HSMODE;
@@ -973,7 +1146,7 @@ static void atmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 
                 if (list_empty(&host->queue)) {
                         atmci_writel(host, ATMCI_MR, host->mode_reg);
-                        if (atmci_is_mci2())
+                        if (host->caps.has_cfg_reg)
                                 atmci_writel(host, ATMCI_CFG, host->cfg_reg);
                 } else {
                         host->need_clock_update = true;
@@ -1088,7 +1261,7 @@ static void atmci_request_end(struct atmel_mci *host, struct mmc_request *mrq)
          */
         if (host->need_clock_update) {
                 atmci_writel(host, ATMCI_MR, host->mode_reg);
-                if (atmci_is_mci2())
+                if (host->caps.has_cfg_reg)
                         atmci_writel(host, ATMCI_CFG, host->cfg_reg);
         }
 
@@ -1137,7 +1310,7 @@ static void atmci_command_complete(struct atmel_mci *host,
                         "command error: status=0x%08x\n", status);
 
                 if (cmd->data) {
-                        atmci_stop_dma(host);
+                        host->stop_transfer(host);
                         host->data = NULL;
                         atmci_writel(host, ATMCI_IDR, ATMCI_NOTBUSY
                                         | ATMCI_TXRDY | ATMCI_RXRDY
@@ -1195,7 +1368,7 @@ static void atmci_detect_change(unsigned long data)
                                 atmci_writel(host, ATMCI_CR, ATMCI_CR_SWRST);
                                 atmci_writel(host, ATMCI_CR, ATMCI_CR_MCIEN);
                                 atmci_writel(host, ATMCI_MR, host->mode_reg);
-                                if (atmci_is_mci2())
+                                if (host->caps.has_cfg_reg)
                                         atmci_writel(host, ATMCI_CFG, host->cfg_reg);
 
                                 host->data = NULL;
@@ -1211,7 +1384,7 @@ static void atmci_detect_change(unsigned long data)
                                         /* fall through */
                                 case STATE_SENDING_DATA:
                                         mrq->data->error = -ENOMEDIUM;
-                                        atmci_stop_dma(host);
+                                        host->stop_transfer(host);
                                         break;
                                 case STATE_DATA_BUSY:
                                 case STATE_DATA_ERROR:
@@ -1290,7 +1463,7 @@ static void atmci_tasklet_func(unsigned long priv)
                 case STATE_SENDING_DATA:
                         if (atmci_test_and_clear_pending(host,
                                                 EVENT_DATA_ERROR)) {
-                                atmci_stop_dma(host);
+                                host->stop_transfer(host);
                                 if (data->stop)
                                         atmci_send_stop_cmd(host, data);
                                 state = STATE_DATA_ERROR;
@@ -1556,6 +1729,56 @@ static irqreturn_t atmci_interrupt(int irq, void *dev_id)
                         atmci_set_pending(host, EVENT_DATA_ERROR);
                         tasklet_schedule(&host->tasklet);
                 }
+
+                if (pending & ATMCI_ENDTX) {
+                        atmci_writel(host, ATMCI_IDR, ATMCI_ENDTX);
+                        if (host->data_size) {
+                                atmci_pdc_set_single_buf(host,
+                                                XFER_TRANSMIT, PDC_SECOND_BUF);
+                                atmci_writel(host, ATMCI_IER, ATMCI_ENDTX);
+                        }
+                }
+
+                if (pending & ATMCI_TXBUFE) {
+                        atmci_writel(host, ATMCI_IDR, ATMCI_TXBUFE);
+                        /*
+                         * We can receive this interruption before having configured
+                         * the second pdc buffer, so we need to reconfigure first and
+                         * second buffers again
+                         */
+                        if (host->data_size) {
+                                atmci_pdc_set_both_buf(host, XFER_TRANSMIT);
+                                atmci_writel(host, ATMCI_IER, ATMCI_TXBUFE);
+                        } else {
+                                atmci_pdc_complete(host);
+                        }
+                }
+
+                if (pending & ATMCI_ENDRX) {
+                        atmci_writel(host, ATMCI_IDR, ATMCI_ENDRX);
+
+                        if (host->data_size) {
+                                atmci_pdc_set_single_buf(host,
+                                                XFER_RECEIVE, PDC_SECOND_BUF);
+                                atmci_writel(host, ATMCI_IER, ATMCI_ENDRX);
+                        }
+                }
+
+                if (pending & ATMCI_RXBUFF) {
+                        atmci_writel(host, ATMCI_IDR, ATMCI_RXBUFF);
+                        /*
+                         * We can receive this interruption before having configured
+                         * the second pdc buffer, so we need to reconfigure first and
+                         * second buffers again
+                         */
+                        if (host->data_size) {
+                                atmci_pdc_set_both_buf(host, XFER_RECEIVE);
+                                atmci_writel(host, ATMCI_IER, ATMCI_RXBUFF);
+                        } else {
+                                atmci_pdc_complete(host);
+                        }
+                }
+
                 if (pending & ATMCI_NOTBUSY) {
                         atmci_writel(host, ATMCI_IDR,
                                         ATMCI_DATA_ERROR_FLAGS | ATMCI_NOTBUSY);
@@ -1622,7 +1845,7 @@ static int __init atmci_init_slot(struct atmel_mci *host,
         mmc->ocr_avail  = MMC_VDD_32_33 | MMC_VDD_33_34;
         if (sdio_irq)
                 mmc->caps |= MMC_CAP_SDIO_IRQ;
-        if (atmci_is_mci2())
+        if (host->caps.has_highspeed)
                 mmc->caps |= MMC_CAP_SD_HIGHSPEED;
         if (slot_data->bus_width >= 4)
                 mmc->caps |= MMC_CAP_4_BIT_DATA;
@@ -1705,7 +1928,6 @@ static void __exit atmci_cleanup_slot(struct atmel_mci_slot *slot,
         mmc_free_host(slot->mmc);
 }
 
-#ifdef CONFIG_MMC_ATMELMCI_DMA
 static bool atmci_filter(struct dma_chan *chan, void *slave)
 {
         struct mci_dma_data     *sl = slave;
@@ -1747,9 +1969,60 @@ static void atmci_configure_dma(struct atmel_mci *host)
                                         "Using %s for DMA transfers\n",
                                         dma_chan_name(host->dma.chan));
 }
+
+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
+ * PDC.
+ */
+static void __init atmci_get_cap(struct atmel_mci *host)
+{
+        unsigned int version;
+
+        version = atmci_get_version(host);
+        dev_info(&host->pdev->dev,
+                        "version: 0x%x\n", version);
+
+        host->caps.has_dma = 0;
+        host->caps.has_pdc = 0;
+        host->caps.has_cfg_reg = 0;
+        host->caps.has_cstor_reg = 0;
+        host->caps.has_highspeed = 0;
+        host->caps.has_rwproof = 0;
+
+        /* keep only major version number */
+        switch (version & 0xf00) {
+        case 0x100:
+        case 0x200:
+                host->caps.has_pdc = 1;
+                host->caps.has_rwproof = 1;
+                break;
+        case 0x300:
+        case 0x400:
+        case 0x500:
+#ifdef CONFIG_AT_HDMAC
+                host->caps.has_dma = 1;
 #else
-static void atmci_configure_dma(struct atmel_mci *host) {}
+                host->caps.has_dma = 0;
+                dev_info(&host->pdev->dev,
+                        "has dma capability but dma engine is not selected, then use pio\n");
 #endif
+                host->caps.has_cfg_reg = 1;
+                host->caps.has_cstor_reg = 1;
+                host->caps.has_highspeed = 1;
+                host->caps.has_rwproof = 1;
+                break;
+        default:
+                dev_warn(&host->pdev->dev,
+                                "Unmanaged mci version, set minimum capabilities\n");
+                break;
+        }
+}
 
 static int __init atmci_probe(struct platform_device *pdev)
 {
@@ -1802,7 +2075,27 @@ static int __init atmci_probe(struct platform_device *pdev)
         if (ret)
                 goto err_request_irq;
 
-        atmci_configure_dma(host);
+        /* Get MCI capabilities and set operations according to it */
+        atmci_get_cap(host);
+        if (host->caps.has_dma) {
+                dev_info(&pdev->dev, "using DMA\n");
+                host->prepare_data = &atmci_prepare_data_dma;
+                host->submit_data = &atmci_submit_data_dma;
+                host->stop_transfer = &atmci_stop_transfer_dma;
+        } else if (host->caps.has_pdc) {
+                dev_info(&pdev->dev, "using PDC\n");
+                host->prepare_data = &atmci_prepare_data_pdc;
+                host->submit_data = &atmci_submit_data_pdc;
+                host->stop_transfer = &atmci_stop_transfer_pdc;
+        } else {
+                dev_info(&pdev->dev, "no DMA, no PDC\n");
+                host->prepare_data = &atmci_prepare_data;
+                host->submit_data = &atmci_submit_data;
+                host->stop_transfer = &atmci_stop_transfer;
+        }
+
+        if (host->caps.has_dma)
+                atmci_configure_dma(host);
 
         platform_set_drvdata(pdev, host);
 
@@ -1834,10 +2127,8 @@ static int __init atmci_probe(struct platform_device *pdev)
         return 0;
 
 err_init_slot:
-#ifdef CONFIG_MMC_ATMELMCI_DMA
         if (host->dma.chan)
                 dma_release_channel(host->dma.chan);
-#endif
         free_irq(irq, host);
 err_request_irq:
         iounmap(host->regs);