[RESEND PATCHv1 7/8] mmc: sdhci-msm: Make HS400 tuning follow as per recommeneded HW sequence

Ritesh Harjani
2017-01-10T07:00:51Z

During tuning execution for HS400 mode, HW sequence recommends
to select MCLK_SEL/2(0x3) in VENDOR_SPEC & sdhc msm clock at GCC
to be 400MHZ (nearest supported clk). Add this change in tuning
sequence during HS400 tuning.

Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
---
drivers/mmc/host/sdhci-msm.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
index 84d29dd..fa9bce3 100644
--- a/drivers/mmc/host/sdhci-msm.c
+++ b/drivers/mmc/host/sdhci-msm.c
@@ -151,7 +151,8 @@ static unsigned int msm_get_clock_rate_for_bus_mode(struct sdhci_host *host,
*/
if (ios.timing == MMC_TIMING_UHS_DDR50 ||
ios.timing == MMC_TIMING_MMC_DDR52 ||
- ios.timing == MMC_TIMING_MMC_HS400)
+ ios.timing == MMC_TIMING_MMC_HS400 ||
+ host->flags & SDHCI_HS400_TUNING)
clock *= 2;
return clock;
}
@@ -611,7 +612,8 @@ void sdhci_msm_hc_select_mode(struct sdhci_host *host)
{
struct mmc_ios ios = host->mmc->ios;

- if (ios.timing == MMC_TIMING_MMC_HS400)
+ if (ios.timing == MMC_TIMING_MMC_HS400 ||
+ host->flags & SDHCI_HS400_TUNING)
msm_hc_select_hs400(host);
else
msm_hc_select_default(host);
@@ -831,6 +833,16 @@ static int sdhci_msm_execute_tuning(struct sdhci_host *host, u32 opcode)
ios.timing == MMC_TIMING_UHS_SDR104))
return 0;

+ /*
+ * For HS400 tuning in HS200 timing requires:
+ * - select MCLK/2 in VENDOR_SPEC
+ * - program MCLK to 400MHz (or nearest supported) in GCC
+ */
+ if (host->flags & SDHCI_HS400_TUNING) {
+ sdhci_msm_hc_select_mode(host);
+ msm_set_clock_rate_for_bus_mode(host, ios.clock);
+ }
+
retry:
/* First of all reset the tuning block */
rc = msm_init_cm_dll(host);
--
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