[PATCH v3 5/13] mmc: sunxi: Mask DATA0 when updating the clock

From: Maxime Ripard
Date: Mon Jan 16 2017 - 11:59:36 EST


The A64 MMC controllers need DATA0 to be masked while updating the clock,
otherwise any subsequent command will result in a timeout.

Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
---
drivers/mmc/host/sunxi-mmc.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c
index 51d6388a194e..6bbe61397b7c 100644
--- a/drivers/mmc/host/sunxi-mmc.c
+++ b/drivers/mmc/host/sunxi-mmc.c
@@ -101,6 +101,7 @@
(SDXC_SOFT_RESET | SDXC_FIFO_RESET | SDXC_DMA_RESET)

/* clock control bits */
+#define SDXC_MASK_DATA0 BIT(31)
#define SDXC_CARD_CLOCK_ON BIT(16)
#define SDXC_LOW_POWER_ON BIT(17)

@@ -254,6 +255,9 @@ struct sunxi_mmc_cfg {
/* does the IP block support autocalibration? */
bool can_calibrate;

+ /* Does DATA0 needs to be masked while the clock is updated */
+ bool mask_data0;
+
bool needs_new_timings;
};

@@ -657,10 +661,12 @@ static int sunxi_mmc_oclk_onoff(struct sunxi_mmc_host *host, u32 oclk_en)
u32 rval;

rval = mmc_readl(host, REG_CLKCR);
- rval &= ~(SDXC_CARD_CLOCK_ON | SDXC_LOW_POWER_ON);
+ rval &= ~(SDXC_CARD_CLOCK_ON | SDXC_LOW_POWER_ON | SDXC_MASK_DATA0);

if (oclk_en)
rval |= SDXC_CARD_CLOCK_ON;
+ if (host->cfg->mask_data0)
+ rval |= SDXC_MASK_DATA0;

mmc_writel(host, REG_CLKCR, rval);

@@ -680,6 +686,11 @@ static int sunxi_mmc_oclk_onoff(struct sunxi_mmc_host *host, u32 oclk_en)
return -EIO;
}

+ if (host->cfg->mask_data0) {
+ rval = mmc_readl(host, REG_CLKCR);
+ mmc_writel(host, REG_CLKCR, rval & ~SDXC_MASK_DATA0);
+ }
+
return 0;
}

@@ -1081,6 +1092,7 @@ static const struct sunxi_mmc_cfg sun50i_a64_cfg = {
.idma_des_size_bits = 16,
.clk_delays = NULL,
.can_calibrate = true,
+ .mask_data0 = true,
.needs_new_timings = true,
};

--
git-series 0.8.11