Current dw_mci driver supports a TMOUT register which consists of a 24
bit field (TMOUT[31:8]) for the DATA_TIMEOUT. The maximum value of this
field is 0xFFFFFF, which with a 200MHz clock will give a full DRTO of:
0xFFFFFF / 200000000 => ~84 ms
However, the ARTPEC-8 SoC DWMMC IP version has a TMOUT register with an
extended DATA_TIMEOUT field, which supports longer timers for the DRTO.
In this version the DATA_TIMEOUT field is split into two, which with the
same 200MHz clock as above will allow a maximum timeout of:
((TMOUT[10:8] -1) * 0xFFFFFF + TMOUT[31:11] * 8) / 200000000 => ~587 ms
Add a quirk to support this. The quirk is enabled for ARTPEC-8 SoCs.
Signed-off-by: Mårten Lindahl <marten.lindahl@xxxxxxxx>
---
v2:
- Removed unnecessary comment
- Change 1<<0 to BIT(0)
drivers/mmc/host/dw_mmc-exynos.c | 5 +++++
drivers/mmc/host/dw_mmc.c | 33 ++++++++++++++++++++++++++++----
drivers/mmc/host/dw_mmc.h | 6 ++++++
3 files changed, 40 insertions(+), 4 deletions(-)
diff --git a/drivers/mmc/host/dw_mmc-exynos.c b/drivers/mmc/host/dw_mmc-exynos.c
index 86486e6659de..1b625642c5b4 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 ARTPEC-8 SoCs */
+ 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 f2a14a434bef..45ea9fd97a6a 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -1289,6 +1289,7 @@ static void dw_mci_set_data_timeout(struct dw_mci *host,
{
u32 clk_div, tmout;
u64 tmp;
+ unsigned int tmp2;
clk_div = (mci_readl(host, CLKDIV) & 0xFF) * 2;
if (clk_div == 0)
@@ -1301,10 +1302,28 @@ static void dw_mci_set_data_timeout(struct dw_mci *host,
tmout = 0xFF; /* Set maximum */
/* TMOUT[31:8] (DATA_TIMEOUT) */
- if (!tmp || tmp > 0xFFFFFF)
- tmout |= (0xFFFFFF << 8);
- else
- tmout |= (tmp & 0xFFFFFF) << 8;
+ if (host->quirks & DW_MMC_QUIRK_EXTENDED_TMOUT) {
+ /*
+ * Extended HW timer (max = 0x6FFFFF2):
+ * ((TMOUT[10:8] - 1) * 0xFFFFFF + TMOUT[31:11] * 8)
+ */
+ if (!tmp || tmp > 0x6FFFFF2)
+ tmout |= (0xFFFFFF << 8);
+ else {
+ /* TMOUT[10:8] */
+ tmp2 = (((unsigned int)tmp / 0xFFFFFF) + 1) & 0x7;
+ tmout |= tmp2 << 8;
+
+ /* TMOUT[31:11] */
+ tmp = tmp - ((tmp2 - 1) * 0xFFFFFF);
+ tmout |= (tmp & 0xFFFFF8) << 8;
+ }
+ } else {
+ if (!tmp || tmp > 0xFFFFFF)
+ tmout |= (0xFFFFFF << 8);
+ else
+ tmout |= (tmp & 0xFFFFFF) << 8;
+ }
mci_writel(host, TMOUT, tmout);
dev_dbg(host->dev, "timeout_ns: %u => TMOUT[31:8]: 0x%#08x",
@@ -2005,9 +2024,15 @@ static void dw_mci_set_drto(struct dw_mci *host)
if (drto_div == 0)
drto_div = 1;
+ if (host->quirks & DW_MMC_QUIRK_EXTENDED_TMOUT)
+ drto_clks = (((drto_clks & 0x7) - 1) * 0xFFFFFF) +
+ ((drto_clks & 0xFFFFF8));
+
drto_ms = DIV_ROUND_UP_ULL((u64)MSEC_PER_SEC * drto_clks * drto_div,
host->bus_hz);
+ dev_dbg(host->dev, "drto_ms: %u\n", drto_ms);
+
/* add a bit spare time */
drto_ms += 10;
diff --git a/drivers/mmc/host/dw_mmc.h b/drivers/mmc/host/dw_mmc.h
index 771d5afa3136..3b6510d4a684 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 +224,8 @@ 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 +277,9 @@ 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
