[U-Boot] [PATCH v5 13/21] mmc: dw_mmc: support fifo mode in dwc mmc driver
Simon Glass
sjg at chromium.org
Fri Nov 13 19:13:35 CET 2015
+Pantelis (mmc maintainer)
Hi Lin,
On 10 November 2015 at 03:24, Lin Huang <hl at rock-chips.com> wrote:
> 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;
> }
>
This looks too long to me. Can you first add a patch to move
everything inside the 'if (data)' block to a separate static function?
> + /* only fifo mode need it */
> + if (data->flags == MMC_DATA_READ && host->fifo_mode) {
I think both of these blocks should be in the same 'if (host->fifo_mode)'
In fact, can it be 'if (host->fifo_mode && size)' ?
> + 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;
Then the above line can be common at the end of the if ()/
> + }
> + } 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;
Can this be bool?
> };
>
> struct dwmci_idmac {
> --
> 1.9.1
>
Regards,
Simon
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