Thanks for your feedback, Peng.
On 11/18/2025 11:43 AM, Peng Fan wrote:
On Mon, Nov 10, 2025 at 09:37:31AM -0800, Tanmay Kathpalia wrote:
When f_max parameter is 0 in sdhci_setup_cfg(), the function defaults
to using the maximum frequency from host controller capabilities register
instead of the max-frequency property parsed from device tree.
The max-frequency property from device tree is parsed by mmc_of_parse()
and stored in plat->cfg.f_max, but sdhci_setup_cfg() was being called
with f_max=0, causing it to ignore the device tree value and use the
host capabilities register value instead.
Fix this by passing plat->cfg.f_max to sdhci_setup_cfg() to ensure
the device tree specified maximum frequency is respected over the
hardware default.
Signed-off-by: Tanmay Kathpalia <[email protected]>
Reviewed-by: Balsundar Ponnusamy <[email protected]>
---
drivers/mmc/sdhci-cadence.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/mmc/sdhci-cadence.c b/drivers/mmc/sdhci-cadence.c
index d9fda902076..f31437e5eeb 100644
--- a/drivers/mmc/sdhci-cadence.c
+++ b/drivers/mmc/sdhci-cadence.c
@@ -255,7 +255,7 @@ static int sdhci_cdns_probe(struct udevice *dev)
host->mmc = &plat->mmc;
host->mmc->dev = dev;
- ret = sdhci_setup_cfg(&plat->cfg, host, 0, 0);
+ ret = sdhci_setup_cfg(&plat->cfg, host, plat->cfg.f_max, 0);
plat is allocated by setting plat_auto in U_BOOT_DRIVER, but it is not
zeroed. So f_max maybe a random value if max frequency is not set in
device tree. You need clear it before mmc_of_parse or
change to use dev_read_u32_default for parsing max frequency in mmc_of_parse.
I agree with your suggestion to use dev_read_u32_default in
mmc_of_parse() for parsing the max-frequency property. This will ensure
that plat->cfg.f_max is correctly set from the device tree, and if
max-frequency is not specified, it will default to 0.
Since this change affects mmc-uclass.c in the MMC subsystem, I plan to
submit a separate patch for that update to keep the changes organized.
Regards
Peng
if (ret)
return ret;
--
2.43.7
