Re: [edk2-devel] [PATCH] MdeModulePkg/PciHostBridgeDxe: Add readback after final Cfg-Write

2023-11-08 Thread Laszlo Ersek
On 11/6/23 07:55, Joe L wrote: > (1) I'd like (a) the problem report, and the full reasoning by Ard and > Michael to be captured in the commit message, and (b) *minimally* a hint > at the possible reordering, and at the PCI spec-based workaround, to be > placed in the code comment

Re: [edk2-devel] [PATCH] MdeModulePkg/PciHostBridgeDxe: Add readback after final Cfg-Write

2023-11-05 Thread Joe L
> > (1) I'd like (a) the problem report, and the full reasoning by Ard and > Michael to be captured in the commit message, and (b) *minimally* a hint > at the possible reordering, and at the PCI spec-based workaround, to be > placed in the code comment as well. > Laszlo, please forgive me if

Re: [edk2-devel] [PATCH] MdeModulePkg/PciHostBridgeDxe: Add readback after final Cfg-Write

2023-11-03 Thread Michael Brown
On 03/11/2023 16:03, Kinney, Michael D wrote: PCI Configuration read/write operations are non-posted, so the PCI Configuration write operation should complete without the need for an additional transaction. If you are seeing an issue, then it may be in the implementation of the

Re: [edk2-devel] [PATCH] MdeModulePkg/PciHostBridgeDxe: Add readback after final Cfg-Write

2023-11-03 Thread Michael D Kinney
, Hao A ; Ni, Ray > ; Pedro Falcato ; Michael > Brown > Subject: Re: [edk2-devel] [PATCH] MdeModulePkg/PciHostBridgeDxe: Add > readback after final Cfg-Write > > On 11/3/23 01:03, Joe L wrote: > > From: joelopez333 > > > > REF:https://edk2.groups.io/g/devel/

Re: [edk2-devel] [PATCH] MdeModulePkg/PciHostBridgeDxe: Add readback after final Cfg-Write

2023-11-03 Thread Laszlo Ersek
On 11/3/23 01:03, Joe L wrote: > From: joelopez333 > > REF:https://edk2.groups.io/g/devel/topic/102310377#110456 > > - Add a read after the final PCI Configuration space write > in RootBridgeIoPciAccess. > > - When configuration space is strongly ordered, this ensures > that program

[edk2-devel] [PATCH] MdeModulePkg/PciHostBridgeDxe: Add readback after final Cfg-Write

2023-11-02 Thread Joe L
From: joelopez333 REF:https://edk2.groups.io/g/devel/topic/102310377#110456 - Add a read after the final PCI Configuration space write in RootBridgeIoPciAccess. - When configuration space is strongly ordered, this ensures that program execution cannot continue until the completion is