After commit e992cc3f4859 ("UefiCpuPkg PiSmmCpuDxeSmm: Reduce SMRAM consumption in CpuS3.c", 2021-01-11), it is valid for a CPU S3 Data DXE Driver to set "ACPI_CPU_DATA.PreSmmInitRegisterTable" and/or "ACPI_CPU_DATA.RegisterTable" to 0, in case none of the CPUs needs a register table of the corresponding kind, during S3 resume.
Document this fact in the "UefiCpuPkg/Include/AcpiCpuData.h" header file. Cc: Eric Dong <eric.d...@intel.com> Cc: Philippe Mathieu-Daudé <phi...@redhat.com> Cc: Rahul Kumar <rahul1.ku...@intel.com> Cc: Ray Ni <ray...@intel.com> Cc: Star Zeng <star.z...@intel.com> Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3159 Signed-off-by: Laszlo Ersek <ler...@redhat.com> Reviewed-by: Ray Ni <ray...@intel.com> Reviewed-by: Philippe Mathieu-Daudé <phi...@redhat.com> --- Notes: v2: - no changes, pick up feedback tags UefiCpuPkg/Include/AcpiCpuData.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/UefiCpuPkg/Include/AcpiCpuData.h b/UefiCpuPkg/Include/AcpiCpuData.h index b5a69ad80c88..62a01b2c6bac 100644 --- a/UefiCpuPkg/Include/AcpiCpuData.h +++ b/UefiCpuPkg/Include/AcpiCpuData.h @@ -178,6 +178,8 @@ typedef struct { // If TableLength is > 0, then elements of RegisterTableEntry are used to // initialize the CPU that matches InitialApicId, during an ACPI S3 resume, // before SMBASE relocation is performed. + // If a register table is not required for any one of the CPUs, then + // PreSmmInitRegisterTable may be set to 0. // EFI_PHYSICAL_ADDRESS PreSmmInitRegisterTable; // @@ -187,6 +189,8 @@ typedef struct { // If TableLength is > 0, then elements of RegisterTableEntry are used to // initialize the CPU that matches InitialApicId, during an ACPI S3 resume, // after SMBASE relocation is performed. + // If a register table is not required for any one of the CPUs, then + // RegisterTable may be set to 0. // EFI_PHYSICAL_ADDRESS RegisterTable; // -- 2.19.1.3.g30247aa5d201 -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#70551): https://edk2.groups.io/g/devel/message/70551 Mute This Topic: https://groups.io/mt/79954427/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-