Re: [edk2-devel] [PATCH v2 1/1] MdeModulePkg: UsbBusDxe: Rebuild Descriptor Table

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

> -----Original Message-----
> From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of
> brit.chesley via groups.io
> Sent: Saturday, July 8, 2023 1:07 AM
> To: devel@edk2.groups.io
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Gao, Liming
> <gaoliming@byosoft.com.cn>; Wu, Hao A <hao.a.wu@intel.com>; Ni, Ray
> <ray.ni@intel.com>; Abner Chang <Abner.Chang@amd.com>
> Subject: [edk2-devel] [PATCH v2 1/1] MdeModulePkg: UsbBusDxe: Rebuild
> Descriptor Table
> 
> From: Britton Chesley <Brit.Chesley@amd.com>
> 
> Fixed a bug which led to an ASSERT due to the USB device context being
> maintained after a port reset, but the underlying XHCI context was
> uninitialized. Specifically, Xhc->UsbDevContext is freed after a reset
> and only re-allocates the default [0] enpoint transfer ring. Added build


Really sorry for another question.

My take is that the transfer ring of other endpoints (besides the Default
Control Endpoint) will be re-initialized by the below flow:
UsbSetConfig -> UsbCtrlRequest (USB_REQ_SET_CONFIG) ->
XhcSetConfigCmd(64) -> XhcInitializeEndpointContext(64)

Could you help to elaborate a bit more on what is the issue with the above
(current) flow and why rebuilding the Descriptor Table before UsbSetConfig can
resolve it?

Thanks in advance.

Best Regards,
Hao Wu


> descriptor table call in UsbIoPortReset. BZ 4456
> 
> Cc: Jian J Wang <jian.j.wang@intel.com>
> Cc: Liming Gao <gaoliming@byosoft.com.cn>
> Cc: Hao A Wu <hao.a.wu@intel.com>
> Cc: Ray Ni <ray.ni@intel.com>
> Cc: Abner Chang <Abner.Chang@amd.com>
> Signed-off-by: Britton Chesley <Brit.Chesley@amd.com>
> ---
>  MdeModulePkg/Bus/Usb/UsbBusDxe/UsbBus.c | 26
> ++++++++++++++++++++++++-
>  1 file changed, 25 insertions(+), 1 deletion(-)
> 
> diff --git a/MdeModulePkg/Bus/Usb/UsbBusDxe/UsbBus.c
> b/MdeModulePkg/Bus/Usb/UsbBusDxe/UsbBus.c
> index c25f3cc2f279..a5b798bd8d6c 100644
> --- a/MdeModulePkg/Bus/Usb/UsbBusDxe/UsbBus.c
> +++ b/MdeModulePkg/Bus/Usb/UsbBusDxe/UsbBus.c
> @@ -821,6 +821,7 @@ UsbIoPortReset (
>    EFI_TPL        OldTpl;
>    EFI_STATUS     Status;
>    UINT8          DevAddress;
> +  UINT8          Config;
> 
>    OldTpl = gBS->RaiseTPL (USB_BUS_TPL);
> 
> @@ -882,8 +883,26 @@ UsbIoPortReset (
>    // is in CONFIGURED state.
>    //
>    if (Dev->ActiveConfig != NULL) {
> -    Status = UsbSetConfig (Dev, Dev->ActiveConfig->Desc.ConfigurationValue);
> +    UsbFreeDevDesc (Dev->DevDesc);
> 
> +    Status = UsbRemoveConfig (Dev);
> +    if (EFI_ERROR (Status)) {
> +      DEBUG ((DEBUG_ERROR, "UsbIoPortReset: Failed to remove
> configuration - %r\n", Status));
> +    }
> +
> +    Status = UsbGetMaxPacketSize0 (Dev);
> +    if (EFI_ERROR (Status)) {
> +      DEBUG ((DEBUG_ERROR, "UsbIoPortReset: Failed to get max packet size -
>  %r\n", Status));
> +    }
> +
> +    Status = UsbBuildDescTable (Dev);
> +    if (EFI_ERROR (Status)) {
> +      DEBUG ((DEBUG_ERROR, "UsbIoPortReset: Failed to build descriptor
> table - %r\n", Status));
> +    }
> +
> +    Config = Dev->DevDesc->Configs[0]->Desc.ConfigurationValue;
> +
> +    Status = UsbSetConfig (Dev, Config);
>      if (EFI_ERROR (Status)) {
>        DEBUG ((
>          DEBUG_ERROR,
> @@ -892,6 +911,11 @@ UsbIoPortReset (
>          Status
>          ));
>      }
> +
> +    Status = UsbSelectConfig (Dev, Config);
> +    if (EFI_ERROR (Status)) {
> +      DEBUG ((DEBUG_ERROR, "UsbIoPortReset: Failed to set configuration -
>  %r\n", Status));
> +    }
>    }
> 
>  ON_EXIT:
> --
> 2.36.1
> 
> 
> 
> 
> 



-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#107396): https://edk2.groups.io/g/devel/message/107396
Mute This Topic: https://groups.io/mt/100010162/7686176
Group Owner: devel+owner@edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub [rebecca@openfw.io]
-=-=-=-=-=-=-=-=-=-=-=-