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MX28: Transfer small blocks via PIO in MXS MMC

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Large blocks (> 512b) shall be transfered via DMA to make
things a bit faster.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Wolfgang Denk <wd@denx.de>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Fabio Estevam <festevam@freescale.com>
Cc: Andy Fleming <afleming@freescale.com>
This commit is contained in:
Marek Vasut 2012-07-06 21:25:56 +00:00 committed by Albert ARIBAUD
parent 869833285b
commit 20255900b9
1 changed files with 19 additions and 25 deletions
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44
drivers/mmc/mxsmmc.c
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@ -43,13 +43,6 @@
#include <asm/arch/sys_proto.h>
#include <asm/arch/dma.h>
/*
* CONFIG_MXS_MMC_DMA: This feature is highly experimental and has no
* performance benefit unless you operate the platform with
* data cache enabled. This is disabled by default, enable
* only if you know what you're doing.
*/
struct mxsmmc_priv {
int id;
struct mxs_ssp_regs *regs;
@ -61,8 +54,8 @@ struct mxsmmc_priv {
};
#define MXSMMC_MAX_TIMEOUT 10000
#define MXSMMC_SMALL_TRANSFER 512
#ifndef CONFIG_MXS_MMC_DMA
static int mxsmmc_send_cmd_pio(struct mxsmmc_priv *priv, struct mmc_data *data)
{
struct mxs_ssp_regs *ssp_regs = priv->regs;
@ -98,7 +91,7 @@ static int mxsmmc_send_cmd_pio(struct mxsmmc_priv *priv, struct mmc_data *data)
return timeout ? 0 : COMM_ERR;
}
#else
static int mxsmmc_send_cmd_dma(struct mxsmmc_priv *priv, struct mmc_data *data)
{
uint32_t data_count = data->blocksize * data->blocks;
@ -139,7 +132,6 @@ static int mxsmmc_send_cmd_dma(struct mxsmmc_priv *priv, struct mmc_data *data)
return 0;
}
#endif
/*
* Sends a command out on the bus. Takes the mmc pointer,
@ -271,24 +263,26 @@ mxsmmc_send_cmd(struct mmc *mmc, struct mmc_cmd *cmd, struct mmc_data *data)
if (!data)
return 0;
#ifdef CONFIG_MXS_MMC_DMA
writel(SSP_CTRL1_DMA_ENABLE, &ssp_regs->hw_ssp_ctrl1_set);
if (data->blocksize * data->blocks < MXSMMC_SMALL_TRANSFER) {
writel(SSP_CTRL1_DMA_ENABLE, &ssp_regs->hw_ssp_ctrl1_set);
ret = mxsmmc_send_cmd_dma(priv, data);
if (ret) {
printf("MMC%d: DMA transfer failed\n", mmc->block_dev.dev);
return ret;
}
#else
writel(SSP_CTRL1_DMA_ENABLE, &ssp_regs->hw_ssp_ctrl1_clr);
ret = mxsmmc_send_cmd_dma(priv, data);
if (ret) {
printf("MMC%d: DMA transfer failed\n",
mmc->block_dev.dev);
return ret;
}
} else {
writel(SSP_CTRL1_DMA_ENABLE, &ssp_regs->hw_ssp_ctrl1_clr);
ret = mxsmmc_send_cmd_pio(priv, data);
if (ret) {
printf("MMC%d: Data timeout with command %d (status 0x%08x)!\n",
mmc->block_dev.dev, cmd->cmdidx, reg);
return ret;
ret = mxsmmc_send_cmd_pio(priv, data);
if (ret) {
printf("MMC%d: Data timeout with command %d "
"(status 0x%08x)!\n",
mmc->block_dev.dev, cmd->cmdidx, reg);
return ret;
}
}
#endif
/* Check data errors */
reg = readl(&ssp_regs->hw_ssp_status);