From: Per Forlin <per.for...@stericsson.com> Buffers must be 4-byte aligned due to restrictions that the PL18x FIFO accesses must be done in a 4-byte aligned manner.
Moreover DPSM_DMAREQCTL must be enabled for SDIO to support writes for non 32-byte aligned sg element lengths. In PIO mode any buffer length can be handled as long as the buffer address is 4-byte aligned. Signed-off-by: Ulf Hansson <ulf.hans...@stericsson.com> Signed-off-by: Per Forlin <per.for...@stericsson.com> Signed-off-by: Stefan Nilsson XK <stefan.xk.nils...@stericsson.com> --- drivers/mmc/host/mmci.c | 51 +++++++++++++++++++++++++++++++++++++++++----- drivers/mmc/host/mmci.h | 7 ++++++ 2 files changed, 52 insertions(+), 6 deletions(-) diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c index b949e07..9ea2f13 100644 --- a/drivers/mmc/host/mmci.c +++ b/drivers/mmc/host/mmci.c @@ -45,6 +45,7 @@ static unsigned int fmax = 515633; * struct variant_data - MMCI variant-specific quirks * @clkreg: default value for MCICLOCK register * @clkreg_enable: enable value for MMCICLOCK register + * @dma_sdio_req_ctrl: enable value for DMAREQCTL register for SDIO write * @datalength_bits: number of bits in the MMCIDATALENGTH register * @fifosize: number of bytes that can be written when MMCI_TXFIFOEMPTY * is asserted (likewise for RX) @@ -60,6 +61,7 @@ static unsigned int fmax = 515633; struct variant_data { unsigned int clkreg; unsigned int clkreg_enable; + unsigned int dma_sdio_req_ctrl; unsigned int datalength_bits; unsigned int fifosize; unsigned int fifohalfsize; @@ -102,6 +104,7 @@ static struct variant_data variant_ux500 = { .fifohalfsize = 8 * 4, .clkreg = MCI_CLK_ENABLE, .clkreg_enable = MCI_ST_UX500_HWFCEN, + .dma_sdio_req_ctrl = MCI_ST_DPSM_DMAREQCTL, .datalength_bits = 24, .sdio = true, .st_clkdiv = true, @@ -114,6 +117,7 @@ static struct variant_data variant_ux500v2 = { .fifohalfsize = 8 * 4, .clkreg = MCI_CLK_ENABLE, .clkreg_enable = MCI_ST_UX500_HWFCEN, + .dma_sdio_req_ctrl = MCI_ST_DPSM_DMAREQCTL, .datalength_bits = 24, .sdio = true, .st_clkdiv = true, @@ -123,6 +127,30 @@ static struct variant_data variant_ux500v2 = { }; /* + * Validate mmc prerequisites + */ +static int mmci_validate_data(struct mmci_host *host, + struct mmc_data *data) +{ + if (!data) + return 0; + + if (!is_power_of_2(data->blksz)) { + dev_err(mmc_dev(host->mmc), + "unsupported block size (%d bytes)\n", data->blksz); + return -EINVAL; + } + + if (data->sg->offset & 3) { + dev_err(mmc_dev(host->mmc), + "unsupported alignment (0x%x)\n", data->sg->offset); + return -EINVAL; + } + + return 0; +} + +/* * This must be called with host->lock held */ static void mmci_write_clkreg(struct mmci_host *host, u32 clk) @@ -432,8 +460,12 @@ static int mmci_dma_prep_data(struct mmci_host *host, struct mmc_data *data, if (!chan) return -EINVAL; - /* If less than or equal to the fifo size, don't bother with DMA */ - if (data->blksz * data->blocks <= variant->fifosize) + /* + * If less than or equal to the fifo size, don't bother with DMA. + * SDIO transfers may not be 4-byte aligned, fall back to PIO. + */ + if (data->blksz * data->blocks <= variant->fifosize || + (data->blksz * data->blocks) & 3) return -EINVAL; device = chan->device; @@ -468,6 +500,7 @@ static int mmci_dma_start_data(struct mmci_host *host, unsigned int datactrl) { int ret; struct mmc_data *data = host->data; + struct variant_data *variant = host->variant; ret = mmci_dma_prep_data(host, host->data, NULL); if (ret) @@ -482,6 +515,11 @@ static int mmci_dma_start_data(struct mmci_host *host, unsigned int datactrl) datactrl |= MCI_DPSM_DMAENABLE; + /* Some hardware versions need special flags for SDIO DMA write. */ + if (variant->sdio && host->mmc->card && mmc_card_sdio(host->mmc->card) + && (data->flags & MMC_DATA_WRITE)) + datactrl |= variant->dma_sdio_req_ctrl; + /* Trigger the DMA transfer */ writel(datactrl, host->base + MMCIDATACTRL); @@ -526,6 +564,9 @@ static void mmci_pre_request(struct mmc_host *mmc, struct mmc_request *mrq, if (!data) return; + if (mmci_validate_data(host, mrq->data)) + return; + if (data->host_cookie) { data->host_cookie = 0; return; @@ -1019,10 +1060,8 @@ static void mmci_request(struct mmc_host *mmc, struct mmc_request *mrq) WARN_ON(host->mrq != NULL); - if (mrq->data && !is_power_of_2(mrq->data->blksz)) { - dev_err(mmc_dev(mmc), "unsupported block size (%d bytes)\n", - mrq->data->blksz); - mrq->cmd->error = -EINVAL; + mrq->cmd->error = mmci_validate_data(host, mrq->data); + if (mrq->cmd->error) { mmc_request_done(mmc, mrq); return; } diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h index d437ccf..095c01c 100644 --- a/drivers/mmc/host/mmci.h +++ b/drivers/mmc/host/mmci.h @@ -60,6 +60,13 @@ #define MCI_ST_DPSM_RWMOD (1 << 10) #define MCI_ST_DPSM_SDIOEN (1 << 11) /* Control register extensions in the ST Micro Ux500 versions */ +/* + * DMA request control is required for write + * if transfer size is not 32-byte aligned. + * DMA request control is also needed if the total + * transfer size is 32-byte aligned but any of the + * sg element lengths are not 32-byte aligned. + */ #define MCI_ST_DPSM_DMAREQCTL (1 << 12) #define MCI_ST_DPSM_DBOOTMODEEN (1 << 13) #define MCI_ST_DPSM_BUSYMODE (1 << 14) -- 1.7.5.4 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html