It has been reported that some platforms (odroid-c2) may require
a different tx phase setting to operate at high speed (hs200 and hs400)
To improve the situation, this patch includes tx phase in the tuning
process.
Fixes: d341ca88eead ("mmc: meson-gx: rework tuning function")
Reported-by: Heiner Kallweit <hkallweit1@xxxxxxxxx>
Signed-off-by: Jerome Brunet <jbrunet@xxxxxxxxxxxx>
---
drivers/mmc/host/meson-gx-mmc.c | 19 ++++++++++++++++++-
1 file changed, 18 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c
index 08a55c2e96e1..85745ef179e2 100644
--- a/drivers/mmc/host/meson-gx-mmc.c
+++ b/drivers/mmc/host/meson-gx-mmc.c
@@ -716,6 +716,22 @@ static int meson_mmc_clk_phase_tuning(struct mmc_host *mmc, u32 opcode,
static int meson_mmc_execute_tuning(struct mmc_host *mmc, u32 opcode)
{
struct meson_host *host = mmc_priv(mmc);
+ int ret;
+
+ /*
+ * If this is the initial tuning, try to get a sane Rx starting
+ * phase before doing the actual tuning.
+ */
+ if (!mmc->doing_retune) {
+ ret = meson_mmc_clk_phase_tuning(mmc, opcode, host->rx_clk);
+
+ if (ret)
+ return ret;
+ }
+
+ ret = meson_mmc_clk_phase_tuning(mmc, opcode, host->tx_clk);
+ if (ret)
+ return ret;
return meson_mmc_clk_phase_tuning(mmc, opcode, host->rx_clk);
}
@@ -746,8 +762,9 @@ static void meson_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
if (!IS_ERR(mmc->supply.vmmc))
mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, ios->vdd);
- /* Reset rx phase */
+ /* Reset phases */
clk_set_phase(host->rx_clk, 0);
+ clk_set_phase(host->tx_clk, 270);
break;
--
2.13.5
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