Re: [edk2-devel] [PATCH v3] MdeModulePkg: Enabling OS boot from SD card through UEFI payload

["Wu, Hao A" <hao.a.wu@intel.com>]

(Add missing maintainers/reviewers)

Reviewed-by: Hao A Wu <hao.a.wu@intel.com>
Will wait until early next week for the merging to see if any comment from other reviewers.

Best Regards,
Hao Wu

> -----Original Message-----
> From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Aiman
> Rosli
> Sent: Friday, January 21, 2022 2:53 AM
> To: devel@edk2.groups.io
> Cc: Rosli, Muhammad Aiman <muhammad.aiman.rosli@intel.com>
> Subject: [edk2-devel] [PATCH v3] MdeModulePkg: Enabling OS boot from SD
> card through UEFI payload
> 
> This changes is by adding 50ms delay during voltage switching from 3.3V to
> 1.8V, plus adding a goto Voltage33Retry for 3.3V checking and retrying.
> 
> Signed-off-by: Aiman Rosli <muhammad.aiman.rosli@intel.com>
> ---
>  MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdDevice.c | 39
> +++++++++++++++++--
>  1 file changed, 36 insertions(+), 3 deletions(-)
> 
> diff --git a/MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdDevice.c
> b/MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdDevice.c
> index 662f9f483c..f5a3607e47 100644
> --- a/MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdDevice.c
> +++ b/MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdDevice.c
> @@ -1213,9 +1213,14 @@ SdCardIdentification (
>    UINT32                         PresentState;
>    UINT8                          HostCtrl2;
>    UINTN                          Retry;
> +  BOOLEAN                        ForceVoltage33;
> +
> +  ForceVoltage33 = FALSE;
> 
>    PciIo    = Private->PciIo;
>    PassThru = &Private->PassThru;
> +
> +Voltage33Retry:
>    //
>    // 1. Send Cmd0 to the device
>    //
> @@ -1294,6 +1299,13 @@ SdCardIdentification (
>      return EFI_UNSUPPORTED;
>    }
> 
> +  //
> +  // 1.8V had failed in the previous run, forcing a retry with 3.3V
> + instead  //  if (ForceVoltage33 == TRUE) {
> +    S18r = FALSE;
> +  }
> +
>    //
>    // 5. Repeatly send Acmd41 with supply voltage window to the device.
>    //    Note here we only support the cards complied with SD physical
> @@ -1366,9 +1378,30 @@ SdCardIdentification (
> 
>        SdMmcHcRwMmio (PciIo, Slot, SD_MMC_HC_PRESENT_STATE, TRUE,
> sizeof (PresentState), &PresentState);
>        if (((PresentState >> 20) & 0xF) != 0xF) {
> -        DEBUG ((DEBUG_ERROR, "SdCardIdentification: SwitchVoltage fails with
> PresentState = 0x%x, It should be 0xF\n", PresentState));
> -        Status = EFI_DEVICE_ERROR;
> -        goto Error;
> +        //
> +        // Delay 50 milliseconds in order for clock to stabilize, retry reading the
> SD_MMC_HC_PRESENT_STATE
> +        //
> +        gBS->Stall (50000);
> +        SdMmcHcRwMmio (PciIo, Slot, SD_MMC_HC_PRESENT_STATE, TRUE,
> sizeof (PresentState), &PresentState);
> +        if (((PresentState >> 20) & 0xF) != 0xF) {
> +          DEBUG ((DEBUG_ERROR, "SdCardIdentification: SwitchVoltage fails
> with PresentState = 0x%x, It should be 0xF\n", PresentState));
> +          //
> +          // Reset and reinitialize the slot before the 3.3V retry.
> +          //
> +          Status = SdMmcHcReset (Private, Slot);
> +          if (EFI_ERROR (Status)) {
> +            goto Error;
> +          }
> +
> +          Status = SdMmcHcInitHost (Private, Slot);
> +          if (EFI_ERROR (Status)) {
> +            goto Error;
> +          }
> +
> +          DEBUG ((DEBUG_ERROR, "SdCardIdentification: Switching to 1.8V
> failed, forcing a retry with 3.3V instead\n"));
> +          ForceVoltage33 = TRUE;
> +          goto Voltage33Retry;
> +        }
>        }
>      }
> 
> --
> 2.34.1.windows.1
> 
> 
> 
> 
>