Hi Roman, On 05/14/18 19:35, Ard Biesheuvel wrote: > On 14 May 2018 at 19:28, Roman Bacik <[email protected]> wrote: >> Ard, >> >> Thank you very much for your comment. >> >>> -----Original Message----- >>> From: Ard Biesheuvel [mailto:[email protected]] >>> Sent: Sunday, May 13, 2018 3:25 AM >>> To: Roman Bacik >>> Cc: [email protected]; Ruiyu Ni; Vladimir Olovyannikov >>> Subject: Re: [edk2] [PATCH] Enable using device address when >>> programming BARs >>> >>> On 9 May 2018 at 22:17, Roman Bacik <[email protected]> >>> wrote: >>>> I will upload v2 with the corrected subject - add package name >>>> MdeModulePkg/Bus . >>>> >>> >>> I don't think this is the correct approach. Please use the address >>> translation >>> support that has been added recently to PciHostBridgeDxe and >>> PciHostBridgeLib. >>> >> >> Would you like to see this change: >> >> Address = Base + Node->Offset; >> + if (UseDeviceAddress) >> + Address = TO_DEVICE_ADDRESS(Address, -Base); >> >> Instead of: >> >> - Address = Base + Node->Offset; >> + Address = UseDeviceAddress? Node->Offset: Base + Node->Offset; >> > > No. > > Programming BARs should always involve device addresses, never CPU > addresses. If you wire up the MMIO translation support correctly, the > existing code will already do what you want.
To clarify a bit, please look at the following commits: 1 5bb1866e5383 MdeModulePkg/PciHostBridgeLib.h: add address Translation 2 74d0a339b832 MdeModulePkg/PciHostBridgeDxe: Add support for address translation 3 c03860d05233 MdeModulePkg/PciBus: convert host address to device address 4 dc080d3b61e5 MdeModulePkg/PciBus: return CPU address for GetBarAttributes in particular, as Ard's first response suggests, the new field introduced in commit 5bb1866e5383. The PciHostBridgeLib instance that your platform plugs into MdeModulePkg/PciHostBridgeDxe should populate this field correctly. Then PciHostBridgeDxe and PciBusDxe will do the right thing for you. Thanks Laszlo _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
