Laszlo, We can keep compatibility.
The value of the GUID in the DEC/Include files can be the current SerialDxe FFS FILE_GUID. Then the device path can use the GUID defined in the DEC/Include file and it will have the same value as today. In the future, the SerialDxe FILE_GUID can be changed as needed with no impacts. There is actually a build feature in the DSC file to override the FILE_GUID value of a single module in the module scoped <Defines> section. If these feature was ever used with SerialDxe, then the generated device path would be wrong if EFI_CALLER_ID_GUID is used. Mike > -----Original Message----- > From: devel@edk2.groups.io > [mailto:devel@edk2.groups.io] On Behalf Of Laszlo Ersek > Sent: Monday, June 3, 2019 5:02 AM > To: Kinney, Michael D <michael.d.kin...@intel.com>; > devel@edk2.groups.io; anthony.per...@citrix.com > Cc: Wang, Jian J <jian.j.w...@intel.com>; Ni, Ray > <ray...@intel.com>; Ard Biesheuvel > <ard.biesheu...@linaro.org>; Zeng, Star > <star.z...@intel.com>; Wu, Hao A <hao.a...@intel.com>; > Julien Grall <julien.gr...@arm.com>; Leif Lindholm > <leif.lindh...@linaro.org> > Subject: Re: [edk2-devel] [PATCH 0/4] Define > SERIAL_DXE_FILE_GUID only once > > On 06/01/19 19:00, Kinney, Michael D wrote: > > Anthony, > > > > I am curious. I agree that a GUID can be defined in > DEC file and > > in an include file that is used as a Vendor GUID in a > device path. > > > > Is there any reason that the FILE_GUID for the module > needs to be > > the same GUID value? Is there any code that looks > for an FFS file > > with that GUID value as the FFS file name? > > It's the other way around. > "MdeModulePkg/Universal/SerialDxe" uses its own > FILE_GUID for populating a device path node on a handle > that it creates. Please see in "SerialIo.c": > > SERIAL_DEVICE_PATH mSerialDevicePath = { > { > { HARDWARE_DEVICE_PATH, HW_VENDOR_DP, { sizeof > (VENDOR_DEVICE_PATH), 0} }, > EFI_CALLER_ID_GUID // Use the driver's GUID > }, > > In turn, PlatformBootManagerLib instances have to refer > to this device path (including said FILE_GUID) for > setting up their console UEFI variables. > > > If not, then it would be better to not over use that > GUID value. > > The FILE_GUID of the SerialDxe can be different. > > This would be a valid change, but for that, the device > path protocol installed by SerialDxe should be > decoupled from SerialDxe's own FILE_GUID. > > Dependent on platform circumstances, that could be a > compatibility issue, because the old ConIn / ConOut / > ErrOut variables could stop working (still referencing > the original FILE_GUID in the devpath). > > Thanks! > Laszlo > > > > > Thanks, > > > > Mike > > > >> -----Original Message----- > >> From: devel@edk2.groups.io > >> [mailto:devel@edk2.groups.io] On Behalf Of Anthony > >> PERARD > >> Sent: Wednesday, May 29, 2019 4:37 AM > >> To: devel@edk2.groups.io > >> Cc: Wang, Jian J <jian.j.w...@intel.com>; Ni, Ray > >> <ray...@intel.com>; Ard Biesheuvel > >> <ard.biesheu...@linaro.org>; Zeng, Star > >> <star.z...@intel.com>; Wu, Hao A > <hao.a...@intel.com>; > >> Julien Grall <julien.gr...@arm.com>; Leif Lindholm > >> <leif.lindh...@linaro.org>; Laszlo Ersek > >> <ler...@redhat.com>; Anthony PERARD > >> <anthony.per...@citrix.com> > >> Subject: [edk2-devel] [PATCH 0/4] Define > >> SERIAL_DXE_FILE_GUID only once > >> > >> The macro SERIAL_DXE_FILE_GUID is already been > defined > >> twice and the GUID is > >> been used once without defining the macro. This > patch > >> series define the macro > >> in MdeModulePkg where the SerialDxe is, and replace > all > >> other use by this new > >> one. > >> > >> Note that I haven't build/test those changes, but I > >> have test the first patch > >> by applying a similar change to a patch series I'm > >> working on. > >> > >> Patch series available in this git branch: > >> https://xenbits.xen.org/git- > >> http/people/aperard/ovmf.git br.serial-dxe-guid-v1 > >> > >> Anthony PERARD (4): > >> MdeModulePkg: Add SERIAL_DXE_FILE_GUID > >> ArmVirtPkg/PlatformBootManagerLib: Use > >> SERIAL_DXE_FILE_GUID from > >> MdeModulePkg > >> ArmPkg/PlatformBootManagerLib: Use > >> SERIAL_DXE_FILE_GUID from > >> MdeModulePkg > >> UefiPayloadPkg/PlatformBootManagerLib: Use > >> SERIAL_DXE_FILE_GUID from > >> MdeModulePkg > >> > >> MdeModulePkg/MdeModulePkg.dec | 3 > +++ > >> MdeModulePkg/Include/Guid/SerialDxe.h | 19 > >> +++++++++++++++++++ > >> .../PlatformBootManagerLib/PlatformBm.c | 6 > +-- > >> --- > >> .../PlatformBootManagerLib/PlatformBm.c | 6 > +-- > >> --- > >> .../PlatformBootManagerLib/PlatformConsole.c | 3 > ++- > >> 5 files changed, 26 insertions(+), 11 deletions(-) > >> create mode 100644 > >> MdeModulePkg/Include/Guid/SerialDxe.h > >> > >> -- > >> Anthony PERARD > >> > >> > >> > > > > > -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. 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