2 // Copyright (c) 2011-2015, ARM Limited. All rights reserved.
4 // This program and the accompanying materials
5 // are licensed and made available under the terms and conditions of the BSD License
6 // which accompanies this distribution. The full text of the license may be found at
7 // http://opensource.org/licenses/bsd-license.php
9 // THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
10 // WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
14 #include <AsmMacroIoLib.h>
16 #include <Library/PcdLib.h>
19 #include <Chipset/ArmV7.h>
24 GCC_ASM_IMPORT(CEntryPoint)
25 GCC_ASM_IMPORT(ArmPlatformIsPrimaryCore)
26 GCC_ASM_IMPORT(ArmReadMpidr)
27 GCC_ASM_IMPORT(ArmPlatformPeiBootAction)
28 GCC_ASM_IMPORT(ArmPlatformStackSet)
29 GCC_ASM_EXPORT(_ModuleEntryPoint)
30 GCC_ASM_EXPORT(mSystemMemoryEnd)
32 StartupAddr: .word CEntryPoint
33 mSystemMemoryEnd: .8byte 0
36 ASM_PFX(_ModuleEntryPoint):
37 // Do early platform specific actions
38 bl ASM_PFX(ArmPlatformPeiBootAction)
40 // Get ID of this CPU in Multicore system
41 bl ASM_PFX(ArmReadMpidr)
42 // Keep a copy of the MpId register value
46 // Enter SVC mode, Disable FIQ and IRQ
47 mov r1, #(CPSR_MODE_SVC | CPSR_IRQ | CPSR_FIQ)
50 // Check if we can install the stack at the top of the System Memory or if we need
51 // to install the stacks at the bottom of the Firmware Device (case the FD is located
52 // at the top of the DRAM)
54 ldr r1, mSystemMemoryEnd
56 // Is mSystemMemoryEnd initialized?
58 bne _SetupStackPosition
60 LoadConstantToReg (FixedPcdGet32(PcdSystemMemoryBase), r1)
61 LoadConstantToReg (FixedPcdGet32(PcdSystemMemorySize), r2)
64 // Update the global variable
65 adr r2, mSystemMemoryEnd
69 // r1 = SystemMemoryTop
71 // Calculate Top of the Firmware Device
72 LoadConstantToReg (FixedPcdGet32(PcdFdBaseAddress), r2)
73 LoadConstantToReg (FixedPcdGet32(PcdFdSize), r3)
75 add r3, r3, r2 // r3 = FdTop = PcdFdBaseAddress + PcdFdSize
77 // UEFI Memory Size (stacks are allocated in this region)
78 LoadConstantToReg (FixedPcdGet32(PcdSystemMemoryUefiRegionSize), r4)
81 // Reserve the memory for the UEFI region (contain stacks on its top)
84 // Calculate how much space there is between the top of the Firmware and the Top of the System Memory
85 subs r0, r1, r3 // r0 = SystemMemoryTop - FdTop
86 bmi _SetupStack // Jump if negative (FdTop > SystemMemoryTop). Case when the PrePi is in XIP memory outside of the DRAM
90 // Case the top of stacks is the FdBaseAddress
94 // r1 contains the top of the stack (and the UEFI Memory)
96 // Because the 'push' instruction is equivalent to 'stmdb' (decrement before), we need to increment
97 // one to the top of the stack. We check if incrementing one does not overflow (case of DRAM at the
98 // top of the memory space)
100 bcs _SetupOverflowStack
107 // Case memory at the top of the address space. Ensure the top of the stack is EFI_PAGE_SIZE
109 LoadConstantToReg (EFI_PAGE_MASK, r9)
114 // Calculate the Base of the UEFI Memory
118 // r1 = The top of the Mpcore Stacks
119 // Stack for the primary core = PrimaryCoreStack
120 LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), r2)
123 // Stack for the secondary core = Number of Cores - 1
124 LoadConstantToReg (FixedPcdGet32(PcdCoreCount), r0)
126 LoadConstantToReg (FixedPcdGet32(PcdCPUCoreSecondaryStackSize), r1)
130 // r10 = The base of the MpCore Stacks (primary stack & secondary stacks)
133 //ArmPlatformStackSet(StackBase, MpId, PrimaryStackSize, SecondaryStackSize)
134 LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), r2)
135 LoadConstantToReg (FixedPcdGet32(PcdCPUCoreSecondaryStackSize), r3)
136 bl ASM_PFX(ArmPlatformStackSet)
138 // Is it the Primary Core ?
140 bl ASM_PFX(ArmPlatformIsPrimaryCore)
142 bne _PrepareArguments
150 // Move sec startup address into a data register
151 // Ensure we're jumping to FV version of the code (not boot remapped alias)
154 // Jump to PrePiCore C code
156 // r1 = UefiMemoryBase