On Sun, Apr 07, 2024 at 10:04:51PM +0200, Hans de Goede wrote: > Unlike all other Bay Trail devices I have (quite a few) the BIOS on > the Lenovo Yoga Tablet 2 830 / 1050 and Lenovo Yoga Tablet 2 Pro 1380 (8", > 10" and 13") models sets the SDHCI_SUPPORT_DDR50 bit in the sdcard slots' > SDHCI controller's Caps_1 register which causes Linux to try and use > UHS SDR12 / SDR25 and DDR50 modes on UHS cards. > > These tablets do have 1.8V signalling implemented in the hw level through > the Bay Trail SoC's SD3_1P8EN pin. But trying to use UHS modes leads to > lots of errors like these: > > [ 225.272001] mmc2: Unexpected interrupt 0x04000000. > [ 225.272024] mmc2: sdhci: ============ SDHCI REGISTER DUMP =========== > [ 225.272034] mmc2: sdhci: Sys addr: 0x0712c400 | Version: 0x0000b502 > [ 225.272044] mmc2: sdhci: Blk size: 0x00007200 | Blk cnt: 0x00000007 > [ 225.272054] mmc2: sdhci: Argument: 0x00000000 | Trn mode: 0x00000023 > [ 225.272064] mmc2: sdhci: Present: 0x01e20002 | Host ctl: 0x00000016 > [ 225.272073] mmc2: sdhci: Power: 0x0000000f | Blk gap: 0x00000000 > [ 225.272082] mmc2: sdhci: Wake-up: 0x00000000 | Clock: 0x00000107 > [ 225.272092] mmc2: sdhci: Timeout: 0x0000000e | Int stat: 0x00000001 > [ 225.272101] mmc2: sdhci: Int enab: 0x03ff000b | Sig enab: 0x03ff000b > [ 225.272110] mmc2: sdhci: ACmd stat: 0x00000000 | Slot int: 0x00000001 > [ 225.272119] mmc2: sdhci: Caps: 0x076864b2 | Caps_1: 0x00000004 > [ 225.272129] mmc2: sdhci: Cmd: 0x00000c1b | Max curr: 0x00000000 > [ 225.272138] mmc2: sdhci: Resp[0]: 0x00000c00 | Resp[1]: 0x00000000 > [ 225.272147] mmc2: sdhci: Resp[2]: 0x00000000 | Resp[3]: 0x00000900 > [ 225.272155] mmc2: sdhci: Host ctl2: 0x0000000c > [ 225.272164] mmc2: sdhci: ADMA Err: 0x00000003 | ADMA Ptr: 0x0712c200 > [ 225.272172] mmc2: sdhci: ============================================ > Since sdhci_acpi_slot_int_emmc sets SDHCI_QUIRK2_PRESET_VALUE_BROKEN sdhci_acpi_slot_int_emmc() > I tried setting that for sdhci_acpi_slot_int_sd too and that does makes sdhci_acpi_slot_int_sd() > things mostly work, but the above error still sometimes happen and > regularly access to the card simply freezes for seconds, which are > problems which do not happen with the non UHS SDR50 mode. > > Add a new DMI_QUIRK_SD_NO_1_8_V DMI quirk flag and set that for these > tablets to disable sdcard slot UHS modes by setting SDHCI_QUIRK2_NO_1_8_V > for the sdcard slot when this quirk is set. -- With Best Regards, Andy Shevchenko
