This adds support to the self relocating PrePi instance that is built as a PIE ET_DYN executable. It primarily involves porting the relocation routine to use ELF32 REL entries instead of ELF64 RELA entries which is what AArch64 uses.
Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Ard Biesheuvel <ard.biesheu...@linaro.org> Acked-by: Laszlo Ersek <ler...@redhat.com> --- ArmVirtPkg/PrePi/Arm/ArchPrePi.c | 26 +++ ArmVirtPkg/PrePi/Arm/ModuleEntryPoint.S | 196 ++++++++++++++++++++ ArmVirtPkg/PrePi/ArmVirtPrePiUniCoreRelocatable.inf | 6 +- ArmVirtPkg/PrePi/Scripts/PrePi-PIE.lds | 29 +-- 4 files changed, 242 insertions(+), 15 deletions(-) diff --git a/ArmVirtPkg/PrePi/Arm/ArchPrePi.c b/ArmVirtPkg/PrePi/Arm/ArchPrePi.c new file mode 100644 index 000000000000..2ca9fdf97903 --- /dev/null +++ b/ArmVirtPkg/PrePi/Arm/ArchPrePi.c @@ -0,0 +1,26 @@ +/** @file +* +* Copyright (c) 2011-2013, ARM Limited. All rights reserved. +* +* This program and the accompanying materials +* are licensed and made available under the terms and conditions of the BSD License +* which accompanies this distribution. The full text of the license may be found at +* http://opensource.org/licenses/bsd-license.php +* +* THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, +* WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. +* +**/ + +#include "PrePi.h" + +VOID +ArchInitialize ( + VOID + ) +{ + // Enable Floating Point + if (FixedPcdGet32 (PcdVFPEnabled)) { + ArmEnableVFP (); + } +} diff --git a/ArmVirtPkg/PrePi/Arm/ModuleEntryPoint.S b/ArmVirtPkg/PrePi/Arm/ModuleEntryPoint.S new file mode 100644 index 000000000000..441db36857de --- /dev/null +++ b/ArmVirtPkg/PrePi/Arm/ModuleEntryPoint.S @@ -0,0 +1,196 @@ +// +// Copyright (c) 2011-2013, ARM Limited. All rights reserved. +// Copyright (c) 2015, Linaro Limited. All rights reserved. +// +// This program and the accompanying materials +// are licensed and made available under the terms and conditions of the BSD License +// which accompanies this distribution. The full text of the license may be found at +// http://opensource.org/licenses/bsd-license.php +// +// THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, +// WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. +// +// + +#include <AsmMacroIoLib.h> +#include <Base.h> +#include <Library/PcdLib.h> +#include <AutoGen.h> + +.text +.align 3 + +GCC_ASM_IMPORT(ArmPlatformIsPrimaryCore) +GCC_ASM_IMPORT(ArmReadMpidr) +GCC_ASM_IMPORT(ArmPlatformPeiBootAction) +GCC_ASM_IMPORT(ArmPlatformStackSet) +GCC_ASM_EXPORT(_ModuleEntryPoint) +ASM_GLOBAL ASM_PFX(mSystemMemoryEnd) + +StartupAddr: .long ASM_PFX(CEntryPoint) +ASM_PFX(mSystemMemoryEnd): .quad 0 + +__relocs: + .long __reloc_base - __relocs + .long __reloc_start - __relocs + .long __reloc_end - __relocs + +ASM_PFX(_ModuleEntryPoint): + // + // We are built as a ET_DYN PIE executable, so we need to process all + // relative relocations if we are executing from a different offset than we + // were linked at. This is only possible if we are running from RAM. + // + + adr r12, __relocs + ldrd r4, r5, [r12] + ldr r6, [r12, #8] + + add r4, r4, r12 + add r5, r5, r12 + add r6, r6, r12 + +.Lreloc_loop: + cmp r5, r6 + bhs .Lreloc_done + + // + // AArch32 uses the ELF32 REL format, which means each entry in the + // relocation table consists of + // + // UINT32 offset : the relative offset of the value that needs to + // be relocated + // UINT32 info : relocation type and symbol index (the latter is + // not used for R_ARM_RELATIVE relocations) + // + ldrd r8, r9, [r5], #8 // read offset into r8 and info into r9 + cmp r9, #23 // check info == R_ARM_RELATIVE? + bne .Lreloc_loop // not a relative relocation? then skip + + ldr r9, [r8, r4] // read addend into r9 + add r9, r9, r1 // add image base to addend to get relocated value + str r9, [r8, r4] // write relocated value at offset + b .Lreloc_loop +.Lreloc_done: + + // Do early platform specific actions + bl ASM_PFX(ArmPlatformPeiBootAction) + + // Get ID of this CPU in Multicore system + bl ASM_PFX(ArmReadMpidr) + // Keep a copy of the MpId register value + mov r10, r0 + +// 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 +// at the top of the DRAM) +_SetupStackPosition: + // Compute Top of System Memory + ldr r12, =PcdGet64 (PcdSystemMemoryBase) + ldr r1, [r12] + ldr r12, =PcdGet64 (PcdSystemMemorySize) + ldrd r2, r3, [r12] + + // calculate the top of memory, and record it in mSystemMemoryEnd + adds r2, r2, r1 + sub r2, r2, #1 + addcs r3, r3, #1 + adr r12, mSystemMemoryEnd + strd r2, r3, [r12] + + // truncate the memory used by UEFI to 4 GB range + teq r3, #0 + movne r1, #-1 + moveq r1, r2 + + // Calculate Top of the Firmware Device + ldr r12, =PcdGet64 (PcdFdBaseAddress) + ldr r2, [r12] + ldr r3, =FixedPcdGet32 (PcdFdSize) + sub r3, r3, #1 + add r3, r3, r2 // r3 = FdTop = PcdFdBaseAddress + PcdFdSize + + // UEFI Memory Size (stacks are allocated in this region) + LoadConstantToReg (FixedPcdGet32(PcdSystemMemoryUefiRegionSize), r4) + + // + // Reserve the memory for the UEFI region (contain stacks on its top) + // + + // Calculate how much space there is between the top of the Firmware and the Top of the System Memory + subs r0, r1, r3 // r0 = SystemMemoryTop - FdTop + bmi _SetupStack // Jump if negative (FdTop > SystemMemoryTop). Case when the PrePi is in XIP memory outside of the DRAM + cmp r0, r4 + bge _SetupStack + + // Case the top of stacks is the FdBaseAddress + mov r1, r2 + +_SetupStack: + // r1 contains the top of the stack (and the UEFI Memory) + + // 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 r11, r1, #1 + bcs _SetupOverflowStack + +_SetupAlignedStack: + mov r1, r11 + 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, r11) + and r11, r11, r1 + sub r1, r1, r11 + +_GetBaseUefiMemory: + // Calculate the Base of the UEFI Memory + sub r11, r1, r4 + +_GetStackBase: + // r1 = The top of the Mpcore Stacks + // Stack for the primary core = PrimaryCoreStack + LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), r2) + sub r12, 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 + + // r12 = The base of the MpCore Stacks (primary stack & secondary stacks) + mov r0, r12 + mov r1, r10 + //ArmPlatformStackSet(StackBase, MpId, PrimaryStackSize, SecondaryStackSize) + LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), r2) + LoadConstantToReg (FixedPcdGet32(PcdCPUCoreSecondaryStackSize), r3) + bl ASM_PFX(ArmPlatformStackSet) + + // Is it the Primary Core ? + mov r0, r10 + bl ASM_PFX(ArmPlatformIsPrimaryCore) + cmp r0, #1 + bne _PrepareArguments + +_PrepareArguments: + mov r0, r10 + mov r1, r11 + mov r2, r12 + + // Move sec startup address into a data register + // Ensure we're jumping to FV version of the code (not boot remapped alias) + ldr r4, StartupAddr + + // Jump to PrePiCore C code + // r0 = MpId + // r1 = UefiMemoryBase + // r2 = StacksBase + blx r4 + +_NeverReturn: + b _NeverReturn diff --git a/ArmVirtPkg/PrePi/ArmVirtPrePiUniCoreRelocatable.inf b/ArmVirtPkg/PrePi/ArmVirtPrePiUniCoreRelocatable.inf index 966f0185bbda..a4ea5a05b652 100755 --- a/ArmVirtPkg/PrePi/ArmVirtPrePiUniCoreRelocatable.inf +++ b/ArmVirtPkg/PrePi/ArmVirtPrePiUniCoreRelocatable.inf @@ -28,6 +28,10 @@ [Sources.AArch64] AArch64/ArchPrePi.c AArch64/ModuleEntryPoint.S +[Sources.ARM] + Arm/ArchPrePi.c + Arm/ModuleEntryPoint.S + [Packages] MdePkg/MdePkg.dec MdeModulePkg/MdeModulePkg.dec @@ -103,4 +107,4 @@ [Pcd] gArmTokenSpaceGuid.PcdFvBaseAddress [BuildOptions] - GCC:*_*_AARCH64_DLINK_FLAGS = -pie -T $(MODULE_DIR)/Scripts/PrePi-PIE.lds + GCC:*_*_*_DLINK_FLAGS = -pie -T $(MODULE_DIR)/Scripts/PrePi-PIE.lds diff --git a/ArmVirtPkg/PrePi/Scripts/PrePi-PIE.lds b/ArmVirtPkg/PrePi/Scripts/PrePi-PIE.lds index 3c89722dcaab..832ad1474468 100644 --- a/ArmVirtPkg/PrePi/Scripts/PrePi-PIE.lds +++ b/ArmVirtPkg/PrePi/Scripts/PrePi-PIE.lds @@ -1,16 +1,16 @@ -#/** @file -# -# Copyright (c) 2015, Linaro Ltd. All rights reserved.<BR> -# -# This program and the accompanying materials -# are licensed and made available under the terms and conditions of the BSD License -# which accompanies this distribution. The full text of the license may be found at -# http://opensource.org/licenses/bsd-license.php -# -# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, -# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. -# -#**/ +/** @file + + Copyright (c) 2015, Linaro Ltd. All rights reserved.<BR> + + This program and the accompanying materials + are licensed and made available under the terms and conditions of the BSD License + which accompanies this distribution. The full text of the license may be found at + http://opensource.org/licenses/bsd-license.php + + THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, + WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. + +**/ SECTIONS { @@ -25,7 +25,8 @@ SECTIONS . = ALIGN(0x20); PROVIDE(__reloc_start = .); - *(.rela .rela*) + *(.rel .rel.*) + *(.rela .rela.*) PROVIDE(__reloc_end = .); } -- 2.5.0 _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
