mmc: renesas_sdhi: Fix sampling clock position selecting
When tuning each tap is issued CMD19 twice and the result of both runs
recorded in host->taps. If the result is different between the two runs
the wrong sampling clock position was selected. Fix this by merging the
two runs and only keep the result for each tap if it was good in both
sets.
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
(cherry picked from commit 5c99826b27d0afd4c05c2013385b17037f579cf9)
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
diff --git a/drivers/mmc/host/renesas_sdhi_core.c b/drivers/mmc/host/renesas_sdhi_core.c
index 45c015da..f087ac7 100644
--- a/drivers/mmc/host/renesas_sdhi_core.c
+++ b/drivers/mmc/host/renesas_sdhi_core.c
@@ -302,6 +302,18 @@
sd_scc_write32(host, priv, SH_MOBILE_SDHI_SCC_RVSREQ, 0);
/*
+ * When tuning CMD19 is issued twice for each tap, merge the
+ * result requiring the tap to be good in both runs before
+ * considering it for tuning selection.
+ */
+ for (i = 0; i < host->tap_num * 2; i++) {
+ int offset = host->tap_num * (i < host->tap_num ? 1 : -1);
+
+ if (!test_bit(i, host->taps))
+ clear_bit(i + offset, host->taps);
+ }
+
+ /*
* Find the longest consecutive run of successful probes. If that
* is more than SH_MOBILE_SDHI_MAX_TAP probes long then use the
* center index as the tap.
