Hi Ray, Please find my inline comments with [Ted].
Thanks, Ted -----Original Message----- From: Ni, Ray <ray...@intel.com> Sent: Thursday, March 10, 2022 12:15 PM To: Kuo, Ted <ted....@intel.com>; devel@edk2.groups.io Cc: De, Debkumar <debkumar...@intel.com>; Han, Harry <harry....@intel.com>; West, Catharine <catharine.w...@intel.com> Subject: RE: [edk2-devel][PATCH] UefiCpuPkg: Support FFS3 GUID in SearchForBfvBase.asm 3 comments starting with "[Ray]". ;#define EFI_FIRMWARE_FILE_SYSTEM2_GUID \ ; { 0x8c8ce578, 0x8a3d, 0x4f1c, { 0x99, 0x35, 0x89, 0x61, 0x85, 0xc3, 0x2d, 0xd3 } } -%define FFS_GUID_DWORD0 0x8c8ce578 -%define FFS_GUID_DWORD1 0x4f1c8a3d -%define FFS_GUID_DWORD2 0x61893599 -%define FFS_GUID_DWORD3 0xd32dc385 +%define FFS2_GUID_DWORD0 0x8c8ce578 +%define FFS2_GUID_DWORD1 0x4f1c8a3d +%define FFS2_GUID_DWORD2 0x61893599 +%define FFS2_GUID_DWORD3 0xd32dc385 + +;#define EFI_FIRMWARE_FILE_SYSTEM3_GUID \ ; { 0x8c8ce578, 0x3dcb, +0x4dca, { 0xbd, 0x6f, 0x1e, 0x96, 0x89, 0xe7, 0x34, 0x9a } } %define +FFS3_GUID_DWORD0 0x5473c07a %define FFS3_GUID_DWORD1 0x4dca3dcb %define +FFS3_GUID_DWORD2 0x961e6fbd %define FFS3_GUID_DWORD3 0x9a34e789 [Ray] 1. I am not sure if it's the best representation of GUID in NASM? I am not the NASM expert. If there is no recommendation, I am ok with this. [Ted] Somehow the diff doesn't reflect the actual representation in my editor. I'll check and update the patch. BITS 32 @@ -25,6 +32,7 @@ BITS 32 Flat32SearchForBfvBase: xor eax, eax + mov ecx, 2 ; 2: FFS3 GUID, 1: FFS2 GUID, 0: Not Found [Ray] 2. Can you map ECX 2 to FFS2 GUID, ECX 3 to FFS3 GUID? [Ted] Yes, will update in next patch. searchingForBfvHeaderLoop: ; ; We check for a firmware volume at every 4KB address in the top 16MB @@ -32,20 +40,37 @@ searchingForBfvHeaderLoop: ; sub eax, 0x1000 cmp eax, 0xff000000 - jb searchedForBfvHeaderButNotFound + jb searchingForBfvWithOtherFfsGuid + cmp ecx, 2 + jne searchingForFfs2Guid ; - ; Check FFS GUID + ; Check FFS3 GUID ; - cmp dword [eax + 0x10], FFS_GUID_DWORD0 + cmp dword [eax + 0x10], FFS3_GUID_DWORD0 jne searchingForBfvHeaderLoop - cmp dword [eax + 0x14], FFS_GUID_DWORD1 + cmp dword [eax + 0x14], FFS3_GUID_DWORD1 jne searchingForBfvHeaderLoop - cmp dword [eax + 0x18], FFS_GUID_DWORD2 + cmp dword [eax + 0x18], FFS3_GUID_DWORD2 jne searchingForBfvHeaderLoop - cmp dword [eax + 0x1c], FFS_GUID_DWORD3 + cmp dword [eax + 0x1c], FFS3_GUID_DWORD3 jne searchingForBfvHeaderLoop + jmp checkingFvLength +searchingForFfs2Guid: + ; + ; Check FFS2 GUID + ; + cmp dword [eax + 0x10], FFS2_GUID_DWORD0 + jne searchingForBfvHeaderLoop + cmp dword [eax + 0x14], FFS2_GUID_DWORD1 + jne searchingForBfvHeaderLoop + cmp dword [eax + 0x18], FFS2_GUID_DWORD2 + jne searchingForBfvHeaderLoop + cmp dword [eax + 0x1c], FFS2_GUID_DWORD3 + jne searchingForBfvHeaderLoop + +checkingFvLength: [Ray] 3. Why is this label added? [Ted] You meant searchingForBfvWithOtherFfsGuid? This is used to restart a new search with a new target guid before reaching the end of the supported ffs guid list. ; ; Check FV Length ; @@ -57,6 +82,12 @@ searchingForBfvHeaderLoop: jmp searchedForBfvHeaderAndItWasFound +searchingForBfvWithOtherFfsGuid: + xor eax, eax + dec ecx + cmp ecx, 0 + jne searchingForBfvHeaderLoop + searchedForBfvHeaderButNotFound: ; ; Hang if the SEC entry point was not found -- 2.16.2.windows.1 -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#87405): https://edk2.groups.io/g/devel/message/87405 Mute This Topic: https://groups.io/mt/89613429/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-