From ffa19162767aac8d96124bc79d1c8df4af53e04a Mon Sep 17 00:00:00 2001 From: Ruiyu Ni Date: Tue, 9 Jan 2018 16:46:40 +0800 Subject: [PATCH] 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 (cherry picked from commit 579510336e2ccbb22fa706c49baa07969e3d60f6) --- UefiCpuPkg/Library/MtrrLib/MtrrLib.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/UefiCpuPkg/Library/MtrrLib/MtrrLib.c b/UefiCpuPkg/Library/MtrrLib/MtrrLib.c index 4f7c28bf92..ba8fabfd9a 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;