diff options
| author | Tanmay Kathpalia <tanmay.kathpalia@altera.com> | 2026-05-14 11:54:11 -0700 |
|---|---|---|
| committer | Peng Fan <peng.fan@nxp.com> | 2026-07-06 14:06:08 +0800 |
| commit | aa2561443c88c00abf7a6f1f77f4976392409771 (patch) | |
| tree | 899edcbbf61294244d3375c9749fd999025b1986 | |
| parent | 780084d7c07f511da4a39b43277c573156ed42e0 (diff) | |
| download | u-boot-aa2561443c88c00abf7a6f1f77f4976392409771.tar.gz u-boot-aa2561443c88c00abf7a6f1f77f4976392409771.zip | |
mmc: sd: fix redundant 1.8V voltage switch on cold boot with UHS card
When a UHS card successfully negotiates 1.8V signaling during normal
initialization, the host voltage switch is performed as part of the
ACMD41 handshake. Without this fix, the warm-reboot recovery path
would fire again immediately after, switching the host voltage a
second time unnecessarily.
Add a check so the recovery path is only entered when the voltage
switch was not already performed during the current initialization
session.
Fixes: 906ee6785b1c ("mmc: sd: Handle UHS-I voltage signaling without power cycle")
Signed-off-by: Tanmay Kathpalia <tanmay.kathpalia@altera.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
| -rw-r--r-- | drivers/mmc/mmc.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c index f0e38efb262..2e565560656 100644 --- a/drivers/mmc/mmc.c +++ b/drivers/mmc/mmc.c @@ -2721,10 +2721,11 @@ static int mmc_startup(struct mmc *mmc) #if CONFIG_IS_ENABLED(MMC_UHS_SUPPORT) /* - * If the card has already switched to 1.8V signaling, then - * set the signal voltage to 1.8V. + * If voltage switch was skipped during ACMD41 but the card is + * already at 1.8V (retained from a previous session, e.g. warm + * reboot), re-configure the host to match. */ - if (mmc_sd_card_using_v18(mmc)) { + if (!(mmc->ocr & OCR_S18R) && mmc_sd_card_using_v18(mmc)) { /* * During a signal voltage level switch, the clock must be gated * for 5 ms according to the SD spec. |