SDHC MSM controller need 2x clock for MCLK at GCC.
Hence make required changes to have 2x clock for
DDR timing modes.
Signed-off-by: Ritesh Harjani <riteshh@xxxxxxxxxxxxxx>
Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
---
drivers/mmc/host/sdhci-msm.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)
diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
index b96a4a7..41a4ea7 100644
--- a/drivers/mmc/host/sdhci-msm.c
+++ b/drivers/mmc/host/sdhci-msm.c
@@ -637,6 +637,7 @@ static void sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
+ struct mmc_ios curr_ios = host->mmc->ios;
int rc;
if (!clock) {
@@ -645,11 +646,23 @@ static void sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
}
spin_unlock_irq(&host->lock);
+ /*
+ * The SDHC requires internal clock frequency to be double the
+ * actual clock that will be set for DDR mode. The controller
+ * uses the faster clock(100/400MHz) for some of its parts and
+ * send the actual required clock (50/200MHz) to the card.
+ */
+ if ((curr_ios.timing == MMC_TIMING_UHS_DDR50) ||
+ (curr_ios.timing == MMC_TIMING_MMC_DDR52) ||
+ (curr_ios.timing == MMC_TIMING_MMC_HS400))
+ clock *= 2;
+
if (clock != msm_host->clk_rate) {
rc = clk_set_rate(msm_host->clk, clock);
if (rc) {
- pr_err("%s: Failed to set clock at rate %u\n",
- mmc_hostname(host->mmc), clock);
+ pr_err("%s: Failed to set clock at rate %u at timing %d\n",
+ mmc_hostname(host->mmc), clock,
+ curr_ios.timing);
spin_lock_irq(&host->lock);
goto out;
}
--
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