[PATCH v2 2/6] mmc: sunxi: Enable the new timings for the A64 MMC controllers

Maxime Ripard maxime.ripard at free-electrons.com
Mon Jan 9 08:46:51 PST 2017


The A64 MMC controllers need to set a "new timings" bit when a new rate is
set.

The actual meaning of that bit is not clear yet, but not setting it leads
to some corner-case issues, like the CMD53 failing, which is used to
implement SDIO packet aggregation.

Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>
---
 drivers/mmc/host/sunxi-mmc.c | 6 ++++++
 1 file changed, 6 insertions(+), 0 deletions(-)

diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c
index ea9552a0d820..9a860bcac154 100644
--- a/drivers/mmc/host/sunxi-mmc.c
+++ b/drivers/mmc/host/sunxi-mmc.c
@@ -253,6 +253,8 @@ struct sunxi_mmc_cfg {
 
 	/* does the IP block support autocalibration? */
 	bool can_calibrate;
+
+	bool needs_new_timings;
 };
 
 struct sunxi_mmc_host {
@@ -776,6 +778,9 @@ static int sunxi_mmc_clk_set_rate(struct sunxi_mmc_host *host,
 	}
 	mmc_writel(host, REG_CLKCR, rval);
 
+	if (host->cfg->needs_new_timings)
+		mmc_writel(host, REG_SD_NTSR, SDXC_2X_TIMING_MODE);
+
 	ret = sunxi_mmc_clk_set_phase(host, ios, rate);
 	if (ret)
 		return ret;
@@ -1073,6 +1078,7 @@ static const struct sunxi_mmc_cfg sun50i_a64_cfg = {
 	.idma_des_size_bits = 16,
 	.clk_delays = NULL,
 	.can_calibrate = true,
+	.needs_new_timings = true,
 };
 
 static const struct of_device_id sunxi_mmc_of_match[] = {
-- 
git-series 0.8.11



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