Re: [PATCH 4/6] mmc: sdhci-acpi: Disable UHS/1.8V modes on Lenovo Yoga Tablet 2 series sdcard slot

[Andy Shevchenko <andy@xxxxxxxxxx>]

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