When running the ARTPEC-8 DWMMC IP version, and a data error interrupt
comes during a data read transfer, there is no guarantee for the data
transfer over interrupt (DTO) to come within the specified data timeout.
This case is handled by the dto_timer handler which will complete the
request with the comment:
/*
* If DTO interrupt does NOT come in sending data state,
* we should notify the driver to terminate current transfer
* and report a data timeout to the core.
*/
But since the ARTPEC-8 DWMMC IP version, supports an extended TMOUT
register which allows longer timeouts than the non ARTPEC-8 version
does, waiting for the dto_timer to complete the request in error cases
may cause the request to take significantly longer time than necessary.
This is specifically true for the failing steps during tuning of a
device.
Fix this by completing the request when the error interrupt comes. Since
this fix is specific for the ARTPEC-8, a quirk is added.
Signed-off-by: Mårten Lindahl <marten.lindahl@xxxxxxxx>
---
v3:
- Define DW_MMC_QUIRK_EXTENDED_TMOUT.
- Implement DW_MMC_QUIRK_EXTENDED_TMOUT for the ARTPEC-8 SoC.
drivers/mmc/host/dw_mmc-exynos.c | 5 +++++
drivers/mmc/host/dw_mmc.c | 9 +++++++++
drivers/mmc/host/dw_mmc.h | 5 +++++
3 files changed, 19 insertions(+)
diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c
index 4e5612d04504..70ff7597f2b0 100644
--- a/drivers/mmc/host/dw_mmc-exynos.c
+++ b/drivers/mmc/host/dw_mmc-exynos.c
@@ -127,6 +127,11 @@ static int dw_mci_exynos_priv_init(struct dw_mci *host)
DQS_CTRL_GET_RD_DELAY(priv->saved_strobe_ctrl);
}
+ if (priv->ctrl_type == DW_MCI_TYPE_ARTPEC8) {
+ /* Quirk needed for the ARTPEC-8 SoC */
+ host->quirks |= DW_MMC_QUIRK_EXTENDED_TMOUT;
+ }
+
host->bus_hz /= (priv->ciu_div + 1);
return 0;
diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index a7745e193afa..da09a06898c9 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -2762,11 +2762,20 @@ static irqreturn_t dw_mci_interrupt(int irq, void *dev_id)
if (pending & DW_MCI_DATA_ERROR_FLAGS) {
spin_lock(&host->irq_lock);
+ if (host->quirks & DW_MMC_QUIRK_EXTENDED_TMOUT)
+ del_timer(&host->dto_timer);
+
/* if there is an error report DATA_ERROR */
mci_writel(host, RINTSTS, DW_MCI_DATA_ERROR_FLAGS);
host->data_status = pending;
smp_wmb(); /* drain writebuffer */
set_bit(EVENT_DATA_ERROR, &host->pending_events);
+
+ if (host->quirks & DW_MMC_QUIRK_EXTENDED_TMOUT)
+ /* In case of error, we cannot expect a DTO */
+ set_bit(EVENT_DATA_COMPLETE,
+ &host->pending_events);
+
tasklet_schedule(&host->tasklet);
spin_unlock(&host->irq_lock);
diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h
index 0a85d05eaf12..7f1e38621d13 100644
--- a/drivers/mmc/host/dw_mmc.h
+++ b/drivers/mmc/host/dw_mmc.h
@@ -118,6 +118,7 @@ struct dw_mci_dma_slave {
* @part_buf: Simple buffer for partial fifo reads/writes.
* @push_data: Pointer to FIFO push function.
* @pull_data: Pointer to FIFO pull function.
+ * @quirks: Set of quirks that apply to specific versions of the IP.
* @vqmmc_enabled: Status of vqmmc, should be true or false.
* @irq_flags: The flags to be passed to request_irq.
* @irq: The irq value to be passed to request_irq.
@@ -223,6 +224,7 @@ struct dw_mci {
void (*push_data)(struct dw_mci *host, void *buf, int cnt);
void (*pull_data)(struct dw_mci *host, void *buf, int cnt);
+ u32 quirks;
bool vqmmc_enabled;
unsigned long irq_flags; /* IRQ flags */
int irq;
@@ -274,6 +276,9 @@ struct dw_mci_board {
struct dma_pdata *data;
};
+/* Support for longer data read timeout */
+#define DW_MMC_QUIRK_EXTENDED_TMOUT BIT(0)
+
#define DW_MMC_240A 0x240a
#define DW_MMC_280A 0x280a
--
2.20.1
