From 298f83612375bda69e8a7230dfea036e85eda553 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Fri, 5 Aug 2016 16:41:32 +0200 Subject: [PATCH] ArmVirtPkg/PrePi: use correct callee saved regs Both the ARM and the AARCH64 versions of the PrePi code (shared between ArmVirtQemuKernel and ArmVirtXen) 'preserve' values across a function call using registers that are not in fact callee saved. So fix that. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Ard Biesheuvel Acked-by: Laszlo Ersek --- ArmVirtPkg/PrePi/AArch64/ModuleEntryPoint.S | 30 ++++++++++----------- ArmVirtPkg/PrePi/Arm/ModuleEntryPoint.S | 10 +++---- 2 files changed, 20 insertions(+), 20 deletions(-) diff --git a/ArmVirtPkg/PrePi/AArch64/ModuleEntryPoint.S b/ArmVirtPkg/PrePi/AArch64/ModuleEntryPoint.S index 68049d5df2..d6be345418 100644 --- a/ArmVirtPkg/PrePi/AArch64/ModuleEntryPoint.S +++ b/ArmVirtPkg/PrePi/AArch64/ModuleEntryPoint.S @@ -71,7 +71,7 @@ ASM_PFX(_ModuleEntryPoint): // Get ID of this CPU in Multicore system bl ASM_PFX(ArmReadMpidr) // Keep a copy of the MpId register value - mov x10, x0 + mov x20, x0 // Check if we can install the stack at the top of the System Memory or if we need // to install the stacks at the bottom of the Firmware Device (case the FD is located @@ -113,40 +113,40 @@ _SetupStack: // Because the 'push' instruction is equivalent to 'stmdb' (decrement before), we need to increment // one to the top of the stack. We check if incrementing one does not overflow (case of DRAM at the // top of the memory space) - adds x11, x1, #1 + adds x21, x1, #1 b.cs _SetupOverflowStack _SetupAlignedStack: - mov x1, x11 + mov x1, x21 b _GetBaseUefiMemory _SetupOverflowStack: // Case memory at the top of the address space. Ensure the top of the stack is EFI_PAGE_SIZE // aligned (4KB) - LoadConstantToReg (EFI_PAGE_MASK, x11) - and x11, x11, x1 - sub x1, x1, x11 + LoadConstantToReg (EFI_PAGE_MASK, x21) + and x21, x21, x1 + sub x1, x1, x21 _GetBaseUefiMemory: // Calculate the Base of the UEFI Memory - sub x11, x1, x4 + sub x21, x1, x4 _GetStackBase: // r1 = The top of the Mpcore Stacks // Stack for the primary core = PrimaryCoreStack LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), x2) - sub x12, x1, x2 + sub x22, x1, x2 // Stack for the secondary core = Number of Cores - 1 LoadConstantToReg (FixedPcdGet32(PcdCoreCount), x0) sub x0, x0, #1 LoadConstantToReg (FixedPcdGet32(PcdCPUCoreSecondaryStackSize), x1) mul x1, x1, x0 - sub x12, x12, x1 + sub x22, x22, x1 - // x12 = The base of the MpCore Stacks (primary stack & secondary stacks) - mov x0, x12 - mov x1, x10 + // x22 = The base of the MpCore Stacks (primary stack & secondary stacks) + mov x0, x22 + mov x1, x20 //ArmPlatformStackSet(StackBase, MpId, PrimaryStackSize, SecondaryStackSize) LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), x2) LoadConstantToReg (FixedPcdGet32(PcdCPUCoreSecondaryStackSize), x3) @@ -159,9 +159,9 @@ _GetStackBase: bne _PrepareArguments _PrepareArguments: - mov x0, x10 - mov x1, x11 - mov x2, x12 + mov x0, x20 + mov x1, x21 + mov x2, x22 // Move sec startup address into a data register // Ensure we're jumping to FV version of the code (not boot remapped alias) diff --git a/ArmVirtPkg/PrePi/Arm/ModuleEntryPoint.S b/ArmVirtPkg/PrePi/Arm/ModuleEntryPoint.S index 441db36857..3215c7d558 100644 --- a/ArmVirtPkg/PrePi/Arm/ModuleEntryPoint.S +++ b/ArmVirtPkg/PrePi/Arm/ModuleEntryPoint.S @@ -154,17 +154,17 @@ _GetStackBase: // r1 = The top of the Mpcore Stacks // Stack for the primary core = PrimaryCoreStack LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), r2) - sub r12, r1, r2 + sub r9, r1, r2 // Stack for the secondary core = Number of Cores - 1 LoadConstantToReg (FixedPcdGet32(PcdCoreCount), r0) sub r0, r0, #1 LoadConstantToReg (FixedPcdGet32(PcdCPUCoreSecondaryStackSize), r1) mul r1, r1, r0 - sub r12, r12, r1 + sub r9, r9, r1 - // r12 = The base of the MpCore Stacks (primary stack & secondary stacks) - mov r0, r12 + // r9 = The base of the MpCore Stacks (primary stack & secondary stacks) + mov r0, r9 mov r1, r10 //ArmPlatformStackSet(StackBase, MpId, PrimaryStackSize, SecondaryStackSize) LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), r2) @@ -180,7 +180,7 @@ _GetStackBase: _PrepareArguments: mov r0, r10 mov r1, r11 - mov r2, r12 + mov r2, r9 // Move sec startup address into a data register // Ensure we're jumping to FV version of the code (not boot remapped alias)