2 // Copyright (c) 2011-2012, 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 AsmMacroIoLib.inc
24 EXPORT _ModuleEntryPoint
27 AREA PrePiCoreEntryPoint, CODE, READONLY
29 StartupAddr DCD CEntryPoint
32 // Get ID of this CPU in Multicore system
34 LoadConstantToReg (FixedPcdGet32(PcdArmPrimaryCoreMask), r1)
38 // Enter SVC mode, Disable FIQ and IRQ
39 mov r1, #0x13 :OR: 0x80 :OR: 0x40
42 // Check if we can install the stack at the top of the System Memory or if we need
43 // to install the stacks at the bottom of the Firmware Device (case the FD is located
44 // at the top of the DRAM)
46 // Compute Top of System Memory
47 LoadConstantToReg (FixedPcdGet32(PcdSystemMemoryBase), r1)
48 LoadConstantToReg (FixedPcdGet32(PcdSystemMemorySize), r2)
50 add r1, r1, r2 // r1 = SystemMemoryTop = PcdSystemMemoryBase + PcdSystemMemorySize
52 // Calculate Top of the Firmware Device
53 LoadConstantToReg (FixedPcdGet32(PcdFdBaseAddress), r2)
54 LoadConstantToReg (FixedPcdGet32(PcdFdSize), r3)
56 add r3, r3, r2 // r3 = FdTop = PcdFdBaseAddress + PcdFdSize
58 // UEFI Memory Size (stacks are allocated in this region)
59 LoadConstantToReg (FixedPcdGet32(PcdSystemMemoryUefiRegionSize), r4)
62 // Reserve the memory for the UEFI region (contain stacks on its top)
65 // Calculate how much space there is between the top of the Firmware and the Top of the System Memory
66 subs r0, r1, r3 // r0 = SystemMemoryTop - FdTop
67 bmi _SetupStack // Jump if negative (FdTop > SystemMemoryTop). Case when the PrePi is in XIP memory outside of the DRAM
71 // Case the top of stacks is the FdBaseAddress
75 // r1 contains the top of the stack (and the UEFI Memory)
77 // Because the 'push' instruction is equivalent to 'stmdb' (decrement before), we need to increment
78 // one to the top of the stack. We check if incrementing one does not overflow (case of DRAM at the
79 // top of the memory space)
81 bcs _SetupOverflowStack
88 // Case memory at the top of the address space. Ensure the top of the stack is EFI_PAGE_SIZE
90 LoadConstantToReg (EFI_PAGE_MASK, r6)
95 // Calculate the Base of the UEFI Memory
99 // Compute Base of Normal stacks for CPU Cores
100 // Is it MpCore system
103 // Case it is not an MP Core system. Just setup the primary core
104 beq _SetupUnicoreStack
107 // r1 = The top of the Mpcore Stacks
108 // Stack for the primary core = PrimaryCoreStack
109 LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), r2)
112 // Stack for the secondary core = Number of Cluster * (4 Core per cluster) * SecondaryStackSize
113 LoadConstantToReg (FixedPcdGet32(PcdClusterCount), r2)
115 LoadConstantToReg (FixedPcdGet32(PcdCPUCoreSecondaryStackSize), r3)
119 // The base of the secondary Stacks = Top of Primary stack
120 LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), r2)
123 // r7 = The base of the MpCore Stacks (primary stack + cluster_count * 4 * secondary stacks)
124 // r1 = The base of the secondary Stacks = Top of the Primary stack
126 // Is it the Primary Core ?
127 LoadConstantToReg (FixedPcdGet32(PcdArmPrimaryCore), r4)
129 beq _SetupPrimaryCoreStack
131 _SetupSecondaryCoreStack
132 // r1 = The base of the secondary Stacks
134 // Get the position of the cores (ClusterId * 4) + CoreId
135 GetCorePositionFromMpId(r0, r5, r4)
136 // The stack starts at the top of the stack region. Add '1' to the Core Position to get the top of the stack
138 // Get the offset for the Secondary Stack
142 bne _PrepareArguments
144 _SetupPrimaryCoreStack
145 // r1 = Top of the primary stack
146 LoadConstantToReg (FixedPcdGet32(PcdPeiGlobalVariableSize), r2)
147 b _PreparePrimaryStack
150 // The top of the Unicore Stack is in r1
151 LoadConstantToReg (FixedPcdGet32(PcdPeiGlobalVariableSize), r2)
152 LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), r3)
154 // Calculate the bottom of the primary stack (StackBase)
158 // The reserved space for global variable must be 8-bytes aligned for pushing
159 // 64-bit variable on the stack
160 SetPrimaryStack (r1, r2, r3)
168 // Move sec startup address into a data register
169 // Ensure we're jumping to FV version of the code (not boot remapped alias)
172 // Jump to PrePiCore C code
174 // r1 = UefiMemoryBase
176 // r3 = GlobalVariableBase