mmc: dw_mmc: support fifo mode in dwc mmc driver

some soc(rk3036 etc) use dw_mmc but do not have internal dma,
so we implement fifo mode to read and write data.

Signed-off-by: Lin Huang <hl@rock-chips.com>
Acked-by: Simon Glass <sjg@chromium.org>

diff --git a/drivers/mmc/dw_mmc.c b/drivers/mmc/dw_mmc.c
index bee8fab332d6ae2605c7e083826d08e9602dcd4a..909e3caf18b142a36abc96ddce626d1d10220394 100644 (file)
--- a/drivers/mmc/dw_mmc.c
+++ b/drivers/mmc/dw_mmc.c
@@ -94,12 +94,21 @@ static void dwmci_prepare_data(struct dwmci_host *host,
        dwmci_writel(host, DWMCI_BYTCNT, data->blocksize * data->blocks);
 }
 
-static int dwmci_data_transfer(struct dwmci_host *host)
+static int dwmci_data_transfer(struct dwmci_host *host, struct mmc_data *data)
 {
        int ret = 0;
-       unsigned int timeout = 240000;
-       u32 mask;
+       u32 timeout = 240000;
+       u32 mask, size, i, len = 0;
+       u32 *buf = NULL;
        ulong start = get_timer(0);
+       u32 fifo_depth = (((host->fifoth_val & RX_WMARK_MASK) >>
+                           RX_WMARK_SHIFT) + 1) * 2;
+
+       size = data->blocksize * data->blocks / 4;
+       if (data->flags == MMC_DATA_READ)
+               buf = (unsigned int *)data->dest;
+       else
+               buf = (unsigned int *)data->src;
 
        for (;;) {
                mask = dwmci_readl(host, DWMCI_RINTSTS);
@@ -110,6 +119,36 @@ static int dwmci_data_transfer(struct dwmci_host *host)
                        break;
                }
 
+               if (host->fifo_mode && size) {
+                       if (data->flags == MMC_DATA_READ) {
+                               if ((dwmci_readl(host, DWMCI_RINTSTS) &&
+                                    DWMCI_INTMSK_RXDR)) {
+                                       len = dwmci_readl(host, DWMCI_STATUS);
+                                       len = (len >> DWMCI_FIFO_SHIFT) &
+                                                   DWMCI_FIFO_MASK;
+                                       for (i = 0; i < len; i++)
+                                               *buf++ =
+                                               dwmci_readl(host, DWMCI_DATA);
+                                       dwmci_writel(host, DWMCI_RINTSTS,
+                                                    DWMCI_INTMSK_RXDR);
+                               }
+                       } else {
+                               if ((dwmci_readl(host, DWMCI_RINTSTS) &&
+                                    DWMCI_INTMSK_TXDR)) {
+                                       len = dwmci_readl(host, DWMCI_STATUS);
+                                       len = fifo_depth - ((len >>
+                                                  DWMCI_FIFO_SHIFT) &
+                                                  DWMCI_FIFO_MASK);
+                                       for (i = 0; i < len; i++)
+                                               dwmci_writel(host, DWMCI_DATA,
+                                                            *buf++);
+                                       dwmci_writel(host, DWMCI_RINTSTS,
+                                                    DWMCI_INTMSK_TXDR);
+                               }
+                       }
+                       size = size > len ? (size - len) : 0;
+               }
+
                /* Data arrived correctly. */
                if (mask & DWMCI_INTMSK_DTO) {
                        ret = 0;
@@ -165,17 +204,24 @@ static int dwmci_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
        dwmci_writel(host, DWMCI_RINTSTS, DWMCI_INTMSK_ALL);
 
        if (data) {
-               if (data->flags == MMC_DATA_READ) {
-                       bounce_buffer_start(&bbstate, (void*)data->dest,
-                                           data->blocksize *
-                                           data->blocks, GEN_BB_WRITE);
+               if (host->fifo_mode) {
+                       dwmci_writel(host, DWMCI_BLKSIZ, data->blocksize);
+                       dwmci_writel(host, DWMCI_BYTCNT,
+                                    data->blocksize * data->blocks);
+                       dwmci_wait_reset(host, DWMCI_CTRL_FIFO_RESET);
                } else {
-                       bounce_buffer_start(&bbstate, (void*)data->src,
-                                           data->blocksize *
-                                           data->blocks, GEN_BB_READ);
+                       if (data->flags == MMC_DATA_READ) {
+                               bounce_buffer_start(&bbstate, (void*)data->dest,
+                                               data->blocksize *
+                                               data->blocks, GEN_BB_WRITE);
+                       } else {
+                               bounce_buffer_start(&bbstate, (void*)data->src,
+                                               data->blocksize *
+                                               data->blocks, GEN_BB_READ);
+                       }
+                       dwmci_prepare_data(host, data, cur_idmac,
+                                          bbstate.bounce_buffer);
                }
-               dwmci_prepare_data(host, data, cur_idmac,
-                                  bbstate.bounce_buffer);
        }
 
        dwmci_writel(host, DWMCI_CMDARG, cmd->cmdarg);
@@ -249,12 +295,15 @@ static int dwmci_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
        }
 
        if (data) {
-               ret = dwmci_data_transfer(host);
-
-               ctrl = dwmci_readl(host, DWMCI_CTRL);
-               ctrl &= ~(DWMCI_DMA_EN);
-               dwmci_writel(host, DWMCI_CTRL, ctrl);
-               bounce_buffer_stop(&bbstate);
+               ret = dwmci_data_transfer(host, data);
+
+               /* only dma mode need it */
+               if (!host->fifo_mode) {
+                       ctrl = dwmci_readl(host, DWMCI_CTRL);
+                       ctrl &= ~(DWMCI_DMA_EN);
+                       dwmci_writel(host, DWMCI_CTRL, ctrl);
+                       bounce_buffer_stop(&bbstate);
+               }
        }
 
        udelay(100);

diff --git a/include/dwmmc.h b/include/dwmmc.h
index 25cf42c606c993331ee82cfc314df27524b108d3..05b0817fe1e1834b10bef69f892bd3fdc3d083c6 100644 (file)
--- a/include/dwmmc.h
+++ b/include/dwmmc.h
@@ -105,6 +105,8 @@
 
 /* Status Register */
 #define DWMCI_BUSY             (1 << 9)
+#define DWMCI_FIFO_MASK                0x1ff
+#define DWMCI_FIFO_SHIFT       17
 
 /* FIFOTH Register */
 #define MSIZE(x)               ((x) << 28)
@@ -180,6 +182,9 @@ struct dwmci_host {
        unsigned int (*get_mmc_clk)(struct dwmci_host *host, uint freq);
 
        struct mmc_config cfg;
+
+       /* use fifo mode to read and write data */
+       bool fifo_mode;
 };
 
 struct dwmci_idmac {