[U-Boot] [PATCH v5 13/21] mmc: dw_mmc: support fifo mode in dwc mmc driver

[Lin Huang]

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 at rock-chips.com>
---
 drivers/mmc/dw_mmc.c | 81 +++++++++++++++++++++++++++++++++++++++++++---------
 include/dwmmc.h      |  5 ++++
 2 files changed, 72 insertions(+), 14 deletions(-)

diff --git a/drivers/mmc/dw_mmc.c b/drivers/mmc/dw_mmc.c
index 26d34ae..18be055 100644
--- a/drivers/mmc/dw_mmc.c
+++ b/drivers/mmc/dw_mmc.c
@@ -118,6 +118,8 @@ static int dwmci_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
 	u32 mask, ctrl;
 	ulong start = get_timer(0);
 	struct bounce_buffer bbstate;
+	unsigned int fifo_len, fifo_depth, size;
+	unsigned int *buf = NULL;
 
 	while (dwmci_readl(host, DWMCI_STATUS) & DWMCI_BUSY) {
 		if (get_timer(start) > timeout) {
@@ -129,17 +131,28 @@ 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) {
+			if (data->flags == MMC_DATA_READ)
+				buf = (unsigned int *)data->dest;
+			else
+				buf = (unsigned int *)data->src;
+			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);
@@ -215,6 +228,7 @@ static int dwmci_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
 	if (data) {
 		start = get_timer(0);
 		timeout = 240000;
+		size = data->blocksize * data->blocks / 4;
 		for (;;) {
 			mask = dwmci_readl(host, DWMCI_RINTSTS);
 			/* Error during data transfer. */
@@ -224,6 +238,44 @@ static int dwmci_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
 				break;
 			}
 
+			/* only fifo mode need it */
+			if (data->flags == MMC_DATA_READ && host->fifo_mode) {
+				if ((dwmci_readl(host, DWMCI_RINTSTS) &&
+				     DWMCI_INTMSK_RXDR) && size) {
+					fifo_len = dwmci_readl(host,
+							       DWMCI_STATUS);
+					fifo_len = (fifo_len >> DWMCI_FIFO_SHIFT)
+						    & DWMCI_FIFO_MASK;
+					for (i = 0; i < fifo_len; i++)
+						*buf++ = dwmci_readl(host,
+								DWMCI_DATA);
+					dwmci_writel(host, DWMCI_RINTSTS,
+						     DWMCI_INTMSK_RXDR);
+					size = size > fifo_len ?
+							(size - fifo_len) : 0;
+				}
+			} else if (data->flags == MMC_DATA_WRITE &&
+				   host->fifo_mode) {
+				fifo_depth = (((host->fifoth_val &
+						RX_WMARK_MASK) >>
+						RX_WMARK_SHIFT) + 1) * 2;
+				if ((dwmci_readl(host, DWMCI_RINTSTS) &&
+				     DWMCI_INTMSK_TXDR) && size) {
+					fifo_len = dwmci_readl(host,
+							DWMCI_STATUS);
+					fifo_len = fifo_depth -
+						((fifo_len >> DWMCI_FIFO_SHIFT)
+						& DWMCI_FIFO_MASK);
+					for (i = 0; i < fifo_len; i++)
+						dwmci_writel(host, DWMCI_DATA,
+							     *buf++);
+					dwmci_writel(host, DWMCI_RINTSTS,
+						     DWMCI_INTMSK_TXDR);
+					size = size > fifo_len ?
+							(size - fifo_len) : 0;
+				}
+			}
+
 			/* Data arrived correctly. */
 			if (mask & DWMCI_INTMSK_DTO) {
 				ret = 0;
@@ -241,11 +293,12 @@ static int dwmci_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd,
 
 		dwmci_writel(host, DWMCI_RINTSTS, mask);
 
-		ctrl = dwmci_readl(host, DWMCI_CTRL);
-		ctrl &= ~(DWMCI_DMA_EN);
-		dwmci_writel(host, DWMCI_CTRL, ctrl);
-
-		bounce_buffer_stop(&bbstate);
+		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 25cf42c..8d26e5e 100644
--- 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 */
+	u32 fifo_mode;
 };
 
 struct dwmci_idmac {
-- 
1.9.1