[edk2-devel] [PATCH] MdeModulePkg/Bus/Pci/PciBusDxe: Increase the width of the data read during oprom shadow

[Michael D Kinney]

Sumana,

One minor change below.

>From reviewing the code before this point, it looks like RomBar, RomImageSize, and Image are all aligned
no checking or handling of unaligned start or end needs to be added.

Thanks,

Mike

> -----Original Message-----
> From: devel at edk2.groups.io <devel at edk2.groups.io> On Behalf Of Sumana Venur
> Sent: Thursday, January 7, 2021 6:33 PM
> To: devel at edk2.groups.io
> Cc: Venur, Sumana <sumana.venur at intel.com>
> Subject: [edk2-devel] [PATCH] MdeModulePkg/Bus/Pci/PciBusDxe: Increase the width of the data read during oprom shadow
> 
> REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2989
> 
> Long times spent on shadowing oprom from graphics card to system memory. We are currently using 8 bit read cycles.
> This needs to be wider, at least 32bit reads to reduce the time for oprom shadow
> 
> Signed-off-by: Sumana Venur <sumana.venur at intel.com>
> ---
>  MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c
> index c994ed5fe3..19dceb3f91 100644
> --- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c
> +++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciOptionRomSupport.c
> @@ -521,9 +521,9 @@ LoadOpRomImage (
>      //
>      PciDevice->PciRootBridgeIo->Mem.Read (
>                                        PciDevice->PciRootBridgeIo,
> -                                      EfiPciWidthUint8,
> +                                      EfiPciWidthUint32,
>                                        RomBar,
> -                                      (UINT32) RomImageSize,
> +                                      (UINT32) RomImageSize/4,

Recommend using: RomImageSize / sizeof (UINT32)

>                                        Image
>                                        );
>      RomInMemory = Image;
> --
> 2.16.2.windows.1
> 
> 
> 
> 
> 



-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#70011): https://edk2.groups.io/g/devel/message/70011
Mute This Topic: https://groups.io/mt/79498239/1813853
Group Owner: devel+owner at edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub [edk2-devel-archive at redhat.com]
-=-=-=-=-=-=-=-=-=-=-=-