From 58d8ace12be763351df37cdcf6fdfceb646fb4dd Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Fri, 14 Feb 2020 16:40:26 +0900 Subject: [PATCH] mmc: sdhci: use dma_map_single() instead of flush_cache() before DMA Currently, sdhci_prepare_dma() calls flush_cache() regardless of the DMA direction. Actually, cache invalidation is enough when reading data from the device. This is correctly handled by dma_map_single(), which mimics the DMA-API in Linux kernel. Drivers can be agnostic which cache operation occurs behind the scene. This commit also sanitizes the difference between the virtual address and the dma address. Signed-off-by: Masahiro Yamada --- drivers/mmc/sdhci.c | 51 ++++++++++++++++++++++----------------------- 1 file changed, 25 insertions(+), 26 deletions(-) diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c index ee54d78a28..77a88bc043 100644 --- a/drivers/mmc/sdhci.c +++ b/drivers/mmc/sdhci.c @@ -15,6 +15,7 @@ #include #include #include +#include static void sdhci_reset(struct sdhci_host *host, u8 mask) { @@ -65,8 +66,8 @@ static void sdhci_transfer_pio(struct sdhci_host *host, struct mmc_data *data) } #if CONFIG_IS_ENABLED(MMC_SDHCI_ADMA) -static void sdhci_adma_desc(struct sdhci_host *host, char *buf, u16 len, - bool end) +static void sdhci_adma_desc(struct sdhci_host *host, dma_addr_t dma_addr, + u16 len, bool end) { struct sdhci_adma_desc *desc; u8 attr; @@ -82,9 +83,9 @@ static void sdhci_adma_desc(struct sdhci_host *host, char *buf, u16 len, desc->attr = attr; desc->len = len; desc->reserved = 0; - desc->addr_lo = (dma_addr_t)buf; + desc->addr_lo = lower_32_bits(dma_addr); #ifdef CONFIG_DMA_ADDR_T_64BIT - desc->addr_hi = (u64)buf >> 32; + desc->addr_hi = upper_32_bits(dma_addr); #endif } @@ -94,22 +95,17 @@ static void sdhci_prepare_adma_table(struct sdhci_host *host, uint trans_bytes = data->blocksize * data->blocks; uint desc_count = DIV_ROUND_UP(trans_bytes, ADMA_MAX_LEN); int i = desc_count; - char *buf; + dma_addr_t dma_addr = host->start_addr; host->desc_slot = 0; - if (data->flags & MMC_DATA_READ) - buf = data->dest; - else - buf = (char *)data->src; - while (--i) { - sdhci_adma_desc(host, buf, ADMA_MAX_LEN, false); - buf += ADMA_MAX_LEN; + sdhci_adma_desc(host, dma_addr, ADMA_MAX_LEN, false); + dma_addr += ADMA_MAX_LEN; trans_bytes -= ADMA_MAX_LEN; } - sdhci_adma_desc(host, buf, trans_bytes, true); + sdhci_adma_desc(host, dma_addr, trans_bytes, true); flush_cache((dma_addr_t)host->adma_desc_table, ROUND(desc_count * sizeof(struct sdhci_adma_desc), @@ -125,11 +121,12 @@ static void sdhci_prepare_dma(struct sdhci_host *host, struct mmc_data *data, int *is_aligned, int trans_bytes) { unsigned char ctrl; + void *buf; if (data->flags == MMC_DATA_READ) - host->start_addr = (dma_addr_t)data->dest; + buf = data->dest; else - host->start_addr = (dma_addr_t)data->src; + buf = (void *)data->src; ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL); ctrl &= ~SDHCI_CTRL_DMA_MASK; @@ -139,16 +136,20 @@ static void sdhci_prepare_dma(struct sdhci_host *host, struct mmc_data *data, ctrl |= SDHCI_CTRL_ADMA32; sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL); + if (host->flags & USE_SDMA && + (host->force_align_buffer || + (host->quirks & SDHCI_QUIRK_32BIT_DMA_ADDR && + ((unsigned long)buf & 0x7) != 0x0))) { + *is_aligned = 0; + if (data->flags != MMC_DATA_READ) + memcpy(host->align_buffer, buf, trans_bytes); + buf = host->align_buffer; + } + + host->start_addr = dma_map_single(buf, trans_bytes, + mmc_get_dma_dir(data)); + if (host->flags & USE_SDMA) { - if (host->force_align_buffer || - (host->quirks & SDHCI_QUIRK_32BIT_DMA_ADDR && - (host->start_addr & 0x7) != 0x0)) { - *is_aligned = 0; - host->start_addr = (unsigned long)host->align_buffer; - if (data->flags != MMC_DATA_READ) - memcpy(host->align_buffer, data->src, - trans_bytes); - } sdhci_writel(host, host->start_addr, SDHCI_DMA_ADDRESS); } else if (host->flags & (USE_ADMA | USE_ADMA64)) { sdhci_prepare_adma_table(host, data); @@ -159,8 +160,6 @@ static void sdhci_prepare_dma(struct sdhci_host *host, struct mmc_data *data, sdhci_writel(host, upper_32_bits(host->adma_addr), SDHCI_ADMA_ADDRESS_HI); } - - flush_cache(host->start_addr, ROUND(trans_bytes, ARCH_DMA_MINALIGN)); } #else static void sdhci_prepare_dma(struct sdhci_host *host, struct mmc_data *data, -- 2.25.1