The eSDHC controller on the i.MX53 needs an additional, non spec
compliant CMD12 after a multiblock read with a predefined number of
blocks. Otherwise the internal state machine won't go back to the
idle state.
This commit effectively reverts 5b6b0ad6 (mmc: sdhci-esdhc-imx:
fix for mmc cards on i.MX5), which fixed part of the problem by
making multiblock reads work, however this fix was not sufficient
when multi- and singleblock reads got intermixed.
This implements the recommended workaround (Freescale i.MX Reference
Manual, section 29.6.8 "Multi-block Read") by manually sending a
CMD12 with the RSPTYP bits cleared.
Signed-off-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
---
v2:
- clarified and fixed commit msg
- converted multiblock state to an enum
---
drivers/mmc/host/sdhci-esdhc-imx.c | 37 +++++++++++++++++++++++++++++++++---
1 file changed, 34 insertions(+), 3 deletions(-)
diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index 78ac002..4bc0dd4 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -85,6 +85,12 @@ struct pltfm_imx_data {
struct clk *clk_ipg;
struct clk *clk_ahb;
struct clk *clk_per;
+ enum {
+ NO_CMD_PENDING, /* no multiblock command pending*/
+ MULTIBLK_IN_PROCESS, /* exact multiblock cmd in process */
+ WAIT_FOR_INT, /* sent CMD12, waiting for response INT */
+ } multiblock_status;
+
};
static struct platform_device_id imx_esdhc_devtype[] = {
@@ -154,6 +160,8 @@ static inline void esdhc_clrset_le(struct sdhci_host *host, u32 mask, u32 val, i
static u32 esdhc_readl_le(struct sdhci_host *host, int reg)
{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct pltfm_imx_data *imx_data = pltfm_host->priv;
u32 val = readl(host->ioaddr + reg);
if (unlikely(reg == SDHCI_CAPABILITIES)) {
@@ -175,6 +183,18 @@ static u32 esdhc_readl_le(struct sdhci_host *host, int reg)
val &= ~ESDHC_INT_VENDOR_SPEC_DMA_ERR;
val |= SDHCI_INT_ADMA_ERROR;
}
+
+ /*
+ * mask off the interrupt we get in response to the manually
+ * sent CMD12
+ */
+ if ((imx_data->multiblock_status == WAIT_FOR_INT) &&
+ ((val & SDHCI_INT_RESPONSE) == SDHCI_INT_RESPONSE)) {
+ val &= ~SDHCI_INT_RESPONSE;
+ writel(SDHCI_INT_RESPONSE, host->ioaddr +
+ SDHCI_INT_STATUS);
+ imx_data->multiblock_status = NO_CMD_PENDING;
+ }
}
return val;
@@ -211,6 +231,15 @@ static void esdhc_writel_le(struct sdhci_host *host, u32 val, int reg)
v = readl(host->ioaddr + ESDHC_VENDOR_SPEC);
v &= ~ESDHC_VENDOR_SPEC_SDIO_QUIRK;
writel(v, host->ioaddr + ESDHC_VENDOR_SPEC);
+
+ if (imx_data->multiblock_status == MULTIBLK_IN_PROCESS)
+ {
+ /* send a manual CMD12 with RESPTYP=none */
+ data = MMC_STOP_TRANSMISSION << 24 |
+ SDHCI_CMD_ABORTCMD << 16;
+ writel(data, host->ioaddr + SDHCI_TRANSFER_MODE);
+ imx_data->multiblock_status = WAIT_FOR_INT;
+ }
}
if (unlikely(reg == SDHCI_INT_ENABLE || reg == SDHCI_SIGNAL_ENABLE)) {
@@ -277,11 +306,13 @@ static void esdhc_writew_le(struct sdhci_host *host, u16 val, int reg)
}
return;
case SDHCI_COMMAND:
- if ((host->cmd->opcode == MMC_STOP_TRANSMISSION ||
- host->cmd->opcode == MMC_SET_BLOCK_COUNT) &&
- (imx_data->flags & ESDHC_FLAG_MULTIBLK_NO_INT))
+ if (host->cmd->opcode == MMC_STOP_TRANSMISSION)
val |= SDHCI_CMD_ABORTCMD;
+ if ((host->cmd->opcode == MMC_SET_BLOCK_COUNT) &&
+ (imx_data->flags & ESDHC_FLAG_MULTIBLK_NO_INT))
+ imx_data->multiblock_status = MULTIBLK_IN_PROCESS;
+
if (is_imx6q_usdhc(imx_data))
writel(val << 16,
host->ioaddr + SDHCI_TRANSFER_MODE);
--
1.7.10.4
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