[PATCH] mmc: dw_mmc: change to use recommended reset procedure
From: Sonny Rao <hidden>
Date: 2014-08-05 01:19:56
This patch changes the fifo reset code to follow the reset procedure outlined in the documentation of Synopsys Mobile storage host databook. Signed-off-by: Sonny Rao <redacted> Signed-off-by: Yuvaraj Kumar C D <redacted> Acked-by: Seungwon Jeon <redacted> Signed-off-by: Ulf Hansson <redacted> [sonnyrao: fix compile for !CONFIG_MMC_DW_IDMAC case] --- drivers/mmc/host/dw_mmc.c | 87 ++++++++++++++++++++++++++++++++++------------- drivers/mmc/host/dw_mmc.h | 5 +++ 2 files changed, 69 insertions(+), 23 deletions(-)
diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 1ac227c..39cf54f 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c@@ -111,8 +111,7 @@ static const u8 tuning_blk_pattern_8bit[] = { 0xff, 0x77, 0x77, 0xff, 0x77, 0xbb, 0xdd, 0xee, }; -static inline bool dw_mci_fifo_reset(struct dw_mci *host); -static inline bool dw_mci_ctrl_all_reset(struct dw_mci *host); +static bool dw_mci_reset(struct dw_mci *host); #if defined(CONFIG_DEBUG_FS) static int dw_mci_req_show(struct seq_file *s, void *v)
@@ -1235,7 +1234,7 @@ static int dw_mci_data_complete(struct dw_mci *host, struct mmc_data *data) * After an error, there may be data lingering * in the FIFO */ - dw_mci_fifo_reset(host); + dw_mci_reset(host); } else { data->bytes_xfered = data->blocks * data->blksz; data->error = 0;
@@ -1352,7 +1351,7 @@ static void dw_mci_tasklet_func(unsigned long priv) /* CMD error in data command */ if (mrq->cmd->error && mrq->data) - dw_mci_fifo_reset(host); + dw_mci_reset(host); host->cmd = NULL; host->data = NULL;
@@ -1963,14 +1962,8 @@ static void dw_mci_work_routine_card(struct work_struct *work) } /* Power down slot */ - if (present == 0) { - /* Clear down the FIFO */ - dw_mci_fifo_reset(host); -#ifdef CONFIG_MMC_DW_IDMAC - dw_mci_idmac_reset(host); -#endif - - } + if (present == 0) + dw_mci_reset(host); spin_unlock_bh(&host->lock);
@@ -2208,8 +2201,11 @@ static bool dw_mci_ctrl_reset(struct dw_mci *host, u32 reset) return false; } -static inline bool dw_mci_fifo_reset(struct dw_mci *host) +static bool dw_mci_reset(struct dw_mci *host) { + u32 flags = SDMMC_CTRL_RESET | SDMMC_CTRL_FIFO_RESET; + bool ret = false; + /* * Reseting generates a block interrupt, hence setting * the scatter-gather pointer to NULL.
@@ -2219,15 +2215,60 @@ static inline bool dw_mci_fifo_reset(struct dw_mci *host) host->sg = NULL; } - return dw_mci_ctrl_reset(host, SDMMC_CTRL_FIFO_RESET); -} + if (host->use_dma) + flags |= SDMMC_CTRL_DMA_RESET; -static inline bool dw_mci_ctrl_all_reset(struct dw_mci *host) -{ - return dw_mci_ctrl_reset(host, - SDMMC_CTRL_FIFO_RESET | - SDMMC_CTRL_RESET | - SDMMC_CTRL_DMA_RESET); + if (dw_mci_ctrl_reset(host, flags)) { + /* + * In all cases we clear the RAWINTS register to clear any + * interrupts. + */ + mci_writel(host, RINTSTS, 0xFFFFFFFF); + + /* if using dma we wait for dma_req to clear */ + if (host->use_dma) { + unsigned long timeout = jiffies + msecs_to_jiffies(500); + u32 status; + do { + status = mci_readl(host, STATUS); + if (!(status & SDMMC_STATUS_DMA_REQ)) + break; + cpu_relax(); + } while (time_before(jiffies, timeout)); + + if (status & SDMMC_STATUS_DMA_REQ) { + dev_err(host->dev, + "%s: Timeout waiting for dma_req to " + "clear during reset\n", __func__); + goto ciu_out; + } + + /* when using DMA next we reset the fifo again */ + if (!dw_mci_ctrl_reset(host, SDMMC_CTRL_FIFO_RESET)) + goto ciu_out; + } + } else { + /* if the controller reset bit did clear, then set clock regs */ + if (!(mci_readl(host, CTRL) & SDMMC_CTRL_RESET)) { + dev_err(host->dev, "%s: fifo/dma reset bits didn't " + "clear but ciu was reset, doing clock update\n", + __func__); + goto ciu_out; + } + } + +#if IS_ENABLED(CONFIG_MMC_DW_IDMAC) + /* It is also recommended that we reset and reprogram idmac */ + dw_mci_idmac_reset(host); +#endif + + ret = true; + +ciu_out: + /* After a CTRL reset we need to have CIU set clock registers */ + mci_send_cmd(host->cur_slot, SDMMC_CMD_UPD_CLK, 0); + + return ret; } #ifdef CONFIG_OF
@@ -2425,7 +2466,7 @@ int dw_mci_probe(struct dw_mci *host) } /* Reset all blocks */ - if (!dw_mci_ctrl_all_reset(host)) + if (!dw_mci_ctrl_reset(host, SDMMC_CTRL_ALL_RESET_FLAGS)) return -ENODEV; host->dma_ops = host->pdata->dma_ops;
@@ -2612,7 +2653,7 @@ int dw_mci_resume(struct dw_mci *host) } } - if (!dw_mci_ctrl_all_reset(host)) { + if (!dw_mci_ctrl_reset(host, SDMMC_CTRL_ALL_RESET_FLAGS)) { ret = -ENODEV; return ret; }
diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h
index 738fa24..08fd956 100644
--- a/drivers/mmc/host/dw_mmc.h
+++ b/drivers/mmc/host/dw_mmc.h@@ -129,6 +129,7 @@ #define SDMMC_CMD_INDX(n) ((n) & 0x1F) /* Status register defines */ #define SDMMC_GET_FCNT(x) (((x)>>17) & 0x1FFF) +#define SDMMC_STATUS_DMA_REQ BIT(31) /* FIFOTH register defines */ #define SDMMC_SET_FIFOTH(m, r, t) (((m) & 0x7) << 28 | \ ((r) & 0xFFF) << 16 | \
@@ -150,6 +151,10 @@ /* Card read threshold */ #define SDMMC_SET_RD_THLD(v, x) (((v) & 0x1FFF) << 16 | (x)) +/* All ctrl reset bits */ +#define SDMMC_CTRL_ALL_RESET_FLAGS \ + (SDMMC_CTRL_RESET | SDMMC_CTRL_FIFO_RESET | SDMMC_CTRL_DMA_RESET) + /* Register access macros */ #define mci_readl(dev, reg) \ __raw_readl((dev)->regs + SDMMC_##reg)
--
1.8.3.2