Re: ArmPlatformPkg: Allocate VRAM as RuntimeServicesData

[Ryan Harkin <ryan.harkin@linaro.org>]

Hi Evan,

This was sent to the list with no subject line and I wasn't on CC, so
I didn't see it.

Are you still using this patch and want it in, i.e. does it need
review and test?

Cheers,
Ryan.

On 4 March 2016 at 15:57,  <evan.lloyd@arm.com> wrote:
> Code at: https://github.com/EvanLloyd/tianocore/commit/
> From: Sami Mujawar <sami.mujawar@arm.com>
> Date: Thu, 25 Feb 2016 15:07:40 +0000
> Subject: [PATCH] ArmPlatformPkg: Allocate VRAM as RuntimeServicesData
>
> The UEFI specification allows the operating system (OS) to use the
> Graphics Output Protocol (GOP) in the following scenarios:
>  a. as part of the startup process and
>  b. prior to loading of a high performance OS graphics driver
>
> If the VRAM is allocated as BootServicesData, then it is unmapped on
> exit boot services. This prevents GOP usage by the OS post exit boot
> services (the second scenario); as it results in a crash when the VRAM
> is accessed.
>
> This patch fixes the issue by allocating VRAM as RuntimeServicesData.
>
> Code at: https://github.com/EvanLloyd/tianocore/commit/18fab16a63c59c84c71cd81089a55a4081ebe253
>
> Contributed-under: TianoCore Contribution Agreement 1.0
> Signed-off-by: Alexei Fedorov <alexei.fedorov@arm.com>
> Signed-off-by: Girish Pathak <girish.pathak@arm.com>
> Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
> Signed-off-by: Evan Lloyd <evan.lloyd@arm.com>
> ---
>  ArmPlatformPkg/ArmVExpressPkg/Library/HdLcdArmVExpressLib/HdLcdArmVExpress.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/ArmPlatformPkg/ArmVExpressPkg/Library/HdLcdArmVExpressLib/HdLcdArmVExpress.c b/ArmPlatformPkg/ArmVExpressPkg/Library/HdLcdArmVExpressLib/HdLcdArmVExpress.c
> index a578467..4ab8862 100644
> --- a/ArmPlatformPkg/ArmVExpressPkg/Library/HdLcdArmVExpressLib/HdLcdArmVExpress.c
> +++ b/ArmPlatformPkg/ArmVExpressPkg/Library/HdLcdArmVExpressLib/HdLcdArmVExpress.c
> @@ -133,7 +133,7 @@ LcdPlatformGetVram (
>    } else {
>      AllocationType = AllocateAddress;
>    }
> -  Status = gBS->AllocatePages (AllocationType, EfiBootServicesData, EFI_SIZE_TO_PAGES(((UINTN)LCD_VRAM_SIZE)), VramBaseAddress);
> +  Status = gBS->AllocatePages (AllocationType, EfiRuntimeServicesData, EFI_SIZE_TO_PAGES(((UINTN)LCD_VRAM_SIZE)), VramBaseAddress);
>    if (EFI_ERROR(Status)) {
>      return Status;
>    }
> --
> 2.7.0
>
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