This change helps to choose msize, rx_watermark and tx_watermak depending on block size for IDMAC mode. For SDIO block size can be variable, so if these values are set incorrectly, card clock may stop.
Signed-off-by: Seungwon Jeon <[email protected]> --- drivers/mmc/host/dw_mmc.c | 74 ++++++++++++++++++++++++++++++++++++++++++-- drivers/mmc/host/dw_mmc.h | 4 ++ include/linux/mmc/dw_mmc.h | 1 + 3 files changed, 76 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c index 296d4a4..b8ba707 100644 --- a/drivers/mmc/host/dw_mmc.c +++ b/drivers/mmc/host/dw_mmc.c @@ -529,6 +529,47 @@ static void dw_mci_post_req(struct mmc_host *mmc, data->host_cookie = 0; } +static void dw_mci_adjust_fifoth(struct dw_mci *host, struct mmc_data *data) +{ +#ifdef CONFIG_MMC_DW_IDMAC + unsigned int blksz = data->blksz; + const u32 mszs[] = {1, 4, 8, 16, 32, 64, 128, 256}; + u32 fifo_width = 1 << host->data_shift; + u32 blksz_depth = blksz / fifo_width, fifoth_val; + u32 msize = 0, rx_wmark = 1, tx_wmark, tx_wmark_invers; + int idx = (sizeof(mszs) / sizeof(mszs[0])) - 1; + + tx_wmark = (host->fifo_depth) / 2; + tx_wmark_invers = host->fifo_depth - tx_wmark; + + /* + * MSIZE is '1', + * if blksz is not a multiple of the FIFO width + */ + if (blksz % fifo_width) { + msize = 0; + rx_wmark = 1; + goto done; + } + + do { + if (!((blksz_depth % mszs[idx]) || + (tx_wmark_invers % mszs[idx]))) { + msize = idx; + rx_wmark = mszs[idx] - 1; + break; + } + } while (--idx > 0); + /* + * If idx is '0', it won't be tried + * Thus, initial values are uesed + */ +done: + fifoth_val = SDMMC_SET_FIFOTH(msize, rx_wmark, tx_wmark); + mci_writel(host, FIFOTH, fifoth_val); +#endif +} + static int dw_mci_submit_data_dma(struct dw_mci *host, struct mmc_data *data) { int sg_len; @@ -553,6 +594,14 @@ static int dw_mci_submit_data_dma(struct dw_mci *host, struct mmc_data *data) (unsigned long)host->sg_cpu, (unsigned long)host->sg_dma, sg_len); + /* + * Decide the MSIZE and RX/TX Watermark. + * If current block size is same with previous size, + * no need to update fifoth. + */ + if (host->prev_blksz != data->blksz) + dw_mci_adjust_fifoth(host, data); + /* Enable the DMA interface */ temp = mci_readl(host, CTRL); temp |= SDMMC_CTRL_DMA_ENABLE; @@ -603,6 +652,21 @@ static void dw_mci_submit_data(struct dw_mci *host, struct mmc_data *data) temp = mci_readl(host, CTRL); temp &= ~SDMMC_CTRL_DMA_ENABLE; mci_writel(host, CTRL, temp); + + /* + * Use the initial fifoth_val for PIO mode. + * If next issued data may be transfered by DMA mode, + * prev_blksz should be invalidated. + */ + mci_writel(host, FIFOTH, host->fifoth_val); + host->prev_blksz = 0; + } else { + /* + * Keep the current block size. + * It will be used to decide whether to update + * fifoth register next time. + */ + host->prev_blksz = data->blksz; } } @@ -2358,8 +2422,8 @@ int dw_mci_probe(struct dw_mci *host) fifo_size = host->pdata->fifo_depth; } host->fifo_depth = fifo_size; - host->fifoth_val = ((0x2 << 28) | ((fifo_size/2 - 1) << 16) | - ((fifo_size/2) << 0)); + host->fifoth_val = + SDMMC_SET_FIFOTH(0x2, fifo_size / 2 - 1, fifo_size / 2); mci_writel(host, FIFOTH, host->fifoth_val); /* disable clock to CIU */ @@ -2542,8 +2606,12 @@ int dw_mci_resume(struct dw_mci *host) if (host->use_dma && host->dma_ops->init) host->dma_ops->init(host); - /* Restore the old value at FIFOTH register */ + /* + * Restore the initial value at FIFOTH register + * And Invalidate the prev_blksz with zero + */ mci_writel(host, FIFOTH, host->fifoth_val); + host->prev_blksz = 0; mci_writel(host, RINTSTS, 0xFFFFFFFF); mci_writel(host, INTMASK, SDMMC_INT_CMD_DONE | SDMMC_INT_DATA_OVER | diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h index 661c6f9..4002c84 100644 --- a/drivers/mmc/host/dw_mmc.h +++ b/drivers/mmc/host/dw_mmc.h @@ -128,6 +128,10 @@ #define SDMMC_CMD_INDX(n) ((n) & 0x1F) /* Status register defines */ #define SDMMC_GET_FCNT(x) (((x)>>17) & 0x1FFF) +/* FIFOTH register defines */ +#define SDMMC_SET_FIFOTH(m, r, t) (((m) & 0x7) << 28 | \ + ((r) & 0xFFF) << 16 | \ + ((t) & 0xFFF)) /* Internal DMAC interrupt defines */ #define SDMMC_IDMAC_INT_AI BIT(9) #define SDMMC_IDMAC_INT_NI BIT(8) diff --git a/include/linux/mmc/dw_mmc.h b/include/linux/mmc/dw_mmc.h index 198f0fa..4ec9dcc 100644 --- a/include/linux/mmc/dw_mmc.h +++ b/include/linux/mmc/dw_mmc.h @@ -129,6 +129,7 @@ struct dw_mci { struct mmc_request *mrq; struct mmc_command *cmd; struct mmc_data *data; + unsigned int prev_blksz; struct workqueue_struct *card_workqueue; /* DMA interface members*/ -- 1.7.0.4 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
