We already disable SDR104 support on the SynQuacer eMMC controller to work around the need for a special tuning quirk that is difficult to implement without modifying the generic driver, even in the presence of a SD/MMC override protocol designed to carry such quirks.
Unfortunately, as it turns out, DDR50 does not work either with the particular 8 GB Kingston part that has been fitted on the rev0.2/0.3 96board samples. Since the mode UEFI drives the eMMC in is independent from what the OS chooses, and the fact that you would not use eMMC in the first place if performance was a major concern, let's just disable DDR50 as well, and fall back to SDR50 mode. Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Ard Biesheuvel <ard.biesheu...@linaro.org> --- Silicon/Socionext/SynQuacer/Drivers/PlatformDxe/Emmc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/Silicon/Socionext/SynQuacer/Drivers/PlatformDxe/Emmc.c b/Silicon/Socionext/SynQuacer/Drivers/PlatformDxe/Emmc.c index c40b30929d5d..6875dfe6b319 100644 --- a/Silicon/Socionext/SynQuacer/Drivers/PlatformDxe/Emmc.c +++ b/Silicon/Socionext/SynQuacer/Drivers/PlatformDxe/Emmc.c @@ -52,6 +52,7 @@ #define SYNQUACER_CLOCK_CTRL_VAL 0xBC01 #define SD_HC_CAP_SDR104 BIT33 +#define SD_HC_CAP_DDR50 BIT34 #define ESD_CONTROL_RESET_DELAY (20 * 1000) #define IO_CONTROL2_SETTLE_US 3000 @@ -95,7 +96,7 @@ SynQuacerSdMmcCapability ( // quirk that is difficult to support using the generic driver. // Capability = ReadUnaligned64 (SdMmcHcSlotCapability); - Capability &= ~(UINT64)SD_HC_CAP_SDR104; + Capability &= ~(UINT64)(SD_HC_CAP_SDR104 | SD_HC_CAP_DDR50); WriteUnaligned64 (SdMmcHcSlotCapability, Capability); return EFI_SUCCESS; -- 2.11.0 _______________________________________________ edk2-devel mailing list email@example.com https://lists.01.org/mailman/listinfo/edk2-devel