[PATCH v3 12/13] mmc: meson-gx: change default tx phase
From: jbrunet@baylibre.com (Jerome Brunet)
Date: 2017-08-28 14:30:16
Also in:
linux-amlogic, linux-mmc, lkml
Subsystem:
arm/amlogic meson soc support, multimedia card (mmc), secure digital (sd) and sdio subsystem, the rest · Maintainers:
Neil Armstrong, Kevin Hilman, Ulf Hansson, Linus Torvalds
Initial default tx phase was set to 0 while the datasheet recommends 270. Some cards fails to initialize with this setting and eMMC mode DDR52 does not work. Changing this setting to 270 fixes these issues, without any regression so far Reviewed-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> --- drivers/mmc/host/meson-gx-mmc.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c
index 0cffc705bfe3..efffd36c8d77 100644
--- a/drivers/mmc/host/meson-gx-mmc.c
+++ b/drivers/mmc/host/meson-gx-mmc.c@@ -1156,8 +1156,14 @@ static int meson_mmc_probe(struct platform_device *pdev) if (ret) goto free_host; + /* + * Set phases : These values are mostly the datasheet recommended ones + * except for the Tx phase. Datasheet recommends 180 but some cards + * fail at initialisation with it. 270 works just fine, it fixes these + * initialisation issues and enable eMMC DDR52 mode. + */ host->tp.core_phase = 180; - host->tp.tx_phase = 0; + host->tp.tx_phase = 270; host->tp.rx_phase = 0; ret = meson_mmc_clk_init(host);
--
2.9.5