[PATCH] mci: am654-sdhci: Clear SDHCI_CTRL_HISPD bit for some speed modes
Sascha Hauer
s.hauer at pengutronix.de
Thu May 15 07:32:19 PDT 2025
Normally we would set the SDHCI_CTRL_HISPD bit for MMC_TIMING_SD_HS and
MMC_TIMING_MMC_HS. This however doesn't seem to work on AM62x and AM62L
SoCs.
Based on U-Boot commit 27a87c834fd ("mmc: am654_sdhci: Fix HISPD bit
configuration in some lower speed modes") clear the SDHCI_CTRL_HISPD bit
in these modes. Unfortunately I can't find the information in the data
sheet referenced in that commit, so I can't verify it, but it seems
to be necessary not only on AM6548, but on other SoCs as well.
Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
---
drivers/mci/am654-sdhci.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
diff --git a/drivers/mci/am654-sdhci.c b/drivers/mci/am654-sdhci.c
index 2c1fa5d804..8d6fa9c999 100644
--- a/drivers/mci/am654-sdhci.c
+++ b/drivers/mci/am654-sdhci.c
@@ -520,10 +520,20 @@ static void am654_sdhci_set_ios(struct mci_host *mci, struct mci_ios *ios)
val = sdhci_read8(&plat->sdhci, SDHCI_HOST_CONTROL);
- if (ios->clock > 26000000)
- val |= SDHCI_CTRL_HISPD;
- else
+ switch (ios->timing) {
+ /*
+ * According to the data manual, HISPD bit
+ * should not be set in these speed modes.
+ */
+ case MMC_TIMING_SD_HS:
+ case MMC_TIMING_MMC_HS:
+ case MMC_TIMING_LEGACY:
val &= ~SDHCI_CTRL_HISPD;
+ break;
+ default:
+ val |= SDHCI_CTRL_HISPD;
+ break;
+ }
sdhci_write8(&plat->sdhci, SDHCI_HOST_CONTROL, val);
--
2.39.5
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