audk/ArmPlatformPkg/PrePi/AArch64/ModuleEntryPoint.S

147 lines
4.7 KiB
ArmAsm

//
// 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 <AsmMacroIoLibV8.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)
StartupAddr: .dword ASM_PFX(CEntryPoint)
ASM_PFX(_ModuleEntryPoint):
// 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 x10, x0
_SetSVCMode:
// 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
LoadConstantToReg (FixedPcdGet32(PcdSystemMemoryBase), x1)
LoadConstantToReg (FixedPcdGet32(PcdSystemMemorySize), x2)
sub x2, x2, #1
add x1, x1, x2 // x1 = SystemMemoryTop = PcdSystemMemoryBase + PcdSystemMemorySize
// Calculate Top of the Firmware Device
LoadConstantToReg (FixedPcdGet32(PcdFdBaseAddress), x2)
LoadConstantToReg (FixedPcdGet32(PcdFdSize), x3)
sub x3, x3, #1
add x3, x3, x2 // x3 = FdTop = PcdFdBaseAddress + PcdFdSize
// UEFI Memory Size (stacks are allocated in this region)
LoadConstantToReg (FixedPcdGet32(PcdSystemMemoryUefiRegionSize), x4)
//
// 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 x0, x1, x3 // x0 = SystemMemoryTop - FdTop
b.mi _SetupStack // Jump if negative (FdTop > SystemMemoryTop). Case when the PrePi is in XIP memory outside of the DRAM
cmp x0, x4
b.ge _SetupStack
// Case the top of stacks is the FdBaseAddress
mov x1, x2
_SetupStack:
// x1 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 x11, x1, #1
b.cs _SetupOverflowStack
_SetupAlignedStack:
mov x1, x11
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
_GetBaseUefiMemory:
// Calculate the Base of the UEFI Memory
sub x11, x1, x4
_GetStackBase:
// r1 = The top of the Mpcore Stacks
// Stack for the primary core = PrimaryCoreStack
LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), x2)
sub x12, 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
// x12 = The base of the MpCore Stacks (primary stack & secondary stacks)
mov x0, x12
mov x1, x10
//ArmPlatformStackSet(StackBase, MpId, PrimaryStackSize, SecondaryStackSize)
LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), x2)
LoadConstantToReg (FixedPcdGet32(PcdCPUCoreSecondaryStackSize), x3)
bl ASM_PFX(ArmPlatformStackSet)
// Is it the Primary Core ?
mov x0, x10
bl ASM_PFX(ArmPlatformIsPrimaryCore)
cmp x0, #1
bne _PrepareArguments
_ReserveGlobalVariable:
LoadConstantToReg (FixedPcdGet32(PcdPeiGlobalVariableSize), x0)
// InitializePrimaryStack($GlobalVariableSize, $Tmp1, $Tmp2)
InitializePrimaryStack(x0, x1, x2)
_PrepareArguments:
mov x0, x10
mov x1, x11
mov x2, x12
mov x3, sp
// Move sec startup address into a data register
// Ensure we're jumping to FV version of the code (not boot remapped alias)
ldr x4, StartupAddr
// Jump to PrePiCore C code
// x0 = MpId
// x1 = UefiMemoryBase
// x2 = StacksBase
// x3 = GlobalVariableBase
blr x4
_NeverReturn:
b _NeverReturn