From: Ruiyu Ni Date: Tue, 9 Jan 2018 08:46:40 +0000 (+0800) Subject: UefiCpuPkg/MtrrLib: Fix a MTRR calculation bug X-Git-Tag: edk2-stable201903~2633 X-Git-Url: https://git.proxmox.com/?p=mirror_edk2.git;a=commitdiff_plain;h=579510336e2ccbb22fa706c49baa07969e3d60f6 UefiCpuPkg/MtrrLib: Fix a MTRR calculation bug 80 A8 B0 B8 C0 +----------WB--------+-UC-+-WT-+-WB-+ For above memory settings, current code caused the final MTRR settings miss [A8, B0, UC] when default memory type is UC. The root cause is the code only checks the mandatory weight between A8 to B0, but skips to check the optional weight. The patch fixes this issue. Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Ruiyu Ni Reviewed-by: Eric Dong --- diff --git a/UefiCpuPkg/Library/MtrrLib/MtrrLib.c b/UefiCpuPkg/Library/MtrrLib/MtrrLib.c index fafa15fd63..768d4d5cff 100644 --- a/UefiCpuPkg/Library/MtrrLib/MtrrLib.c +++ b/UefiCpuPkg/Library/MtrrLib/MtrrLib.c @@ -47,7 +47,7 @@ typedef struct { UINT64 Address; UINT64 Alignment; UINT64 Length; - UINT8 Type : 7; + MTRR_MEMORY_CACHE_TYPE Type : 7; // // Temprary use for calculating the best MTRR settings. @@ -1429,7 +1429,7 @@ MtrrLibCalculateSubtractivePath ( while (SubStart != SubStop) { Status = MtrrLibAppendVariableMtrr ( Mtrrs, MtrrCapacity, MtrrCount, - Vertices[SubStart].Address, Vertices[SubStart].Length, (MTRR_MEMORY_CACHE_TYPE) Vertices[SubStart].Type + Vertices[SubStart].Address, Vertices[SubStart].Length, Vertices[SubStart].Type ); if (RETURN_ERROR (Status)) { return Status; @@ -1450,10 +1450,11 @@ MtrrLibCalculateSubtractivePath ( Pre = Vertices[Cur].Previous; SubStop = Pre; - if (Weight[M (Pre, Cur)] != 0) { + if (Weight[M (Pre, Cur)] + Weight[O (Pre, Cur)] != 0) { Status = MtrrLibAppendVariableMtrr ( Mtrrs, MtrrCapacity, MtrrCount, - Vertices[Pre].Address, Vertices[Cur].Address - Vertices[Pre].Address, LowestPrecedentType + Vertices[Pre].Address, Vertices[Cur].Address - Vertices[Pre].Address, + (Pre != Cur - 1) ? LowestPrecedentType : Vertices[Pre].Type ); if (RETURN_ERROR (Status)) { return Status;