From 20255900b9963a47afb4f3bdc4c9ecb40aaae73b Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Fri, 6 Jul 2012 21:25:56 +0000 Subject: MX28: Transfer small blocks via PIO in MXS MMC Large blocks (> 512b) shall be transfered via DMA to make things a bit faster. Signed-off-by: Marek Vasut Cc: Wolfgang Denk Cc: Stefano Babic Cc: Fabio Estevam Cc: Andy Fleming --- drivers/mmc/mxsmmc.c | 46 ++++++++++++++++++++-------------------------- 1 file changed, 20 insertions(+), 26 deletions(-) (limited to 'drivers') diff --git a/drivers/mmc/mxsmmc.c b/drivers/mmc/mxsmmc.c index 8e2016f..c2aa4aa 100644 --- a/drivers/mmc/mxsmmc.c +++ b/drivers/mmc/mxsmmc.c @@ -43,13 +43,6 @@ #include #include -/* - * 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); - - 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); + if (data->blocksize * data->blocks < MXSMMC_SMALL_TRANSFER) { + writel(SSP_CTRL1_DMA_ENABLE, &ssp_regs->hw_ssp_ctrl1_set); - 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_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; + } } -#endif /* Check data errors */ reg = readl(&ssp_regs->hw_ssp_status); -- cgit v1.1