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| author | ian <ian@FreeBSD.org> | 2015-01-17 19:57:03 +0000 |
|---|---|---|
| committer | ian <ian@FreeBSD.org> | 2015-01-17 19:57:03 +0000 |
| commit | b011ed33bbed20028d149d6090fd65f096b5693f (patch) | |
| tree | 1881198f953b9ee508b3e61f65f78aa2df5f0575 /sys/dev/sdhci/sdhci.h | |
| parent | 730949356cff34f3c184fbbbe7beeadd32537c2e (diff) | |
| download | FreeBSD-src-b011ed33bbed20028d149d6090fd65f096b5693f.zip FreeBSD-src-b011ed33bbed20028d149d6090fd65f096b5693f.tar.gz | |
Add a new SDHCI quirk, SDHCI_QUIRK_DONT_SET_HISPD_BIT. Apparently some
sdhci controllers, such as the one on a Raspberry Pi, mishandle the signal
timing in high speed signaling mode, but run just fine in standard mode
with the bus running at frequencies between 25-50MHz (which shouldn't work).
This is the solution adopted by U-Boot and other OSes (linux and *BSD)
for the timeouts on Raspberry Pi boards with certain SD cards. Some
research shows that this quirk is also used on a few other boards, so the
fix is a generic quirk instead of being in the RPi-specific driver code.
This change is based on information discovered by Michal Meloun.
Diffstat (limited to 'sys/dev/sdhci/sdhci.h')
| -rw-r--r-- | sys/dev/sdhci/sdhci.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/sys/dev/sdhci/sdhci.h b/sys/dev/sdhci/sdhci.h index 80479b7..b7d1960 100644 --- a/sys/dev/sdhci/sdhci.h +++ b/sys/dev/sdhci/sdhci.h @@ -61,6 +61,8 @@ #define SDHCI_QUIRK_DONT_SHIFT_RESPONSE (1<<13) /* Wait to see reset bit asserted before waiting for de-asserted */ #define SDHCI_QUIRK_WAITFOR_RESET_ASSERTED (1<<14) +/* Leave controller in standard mode when putting card in HS mode. */ +#define SDHCI_QUIRK_DONT_SET_HISPD_BIT (1<<15) /* * Controller registers |
