1//
2//  Copyright (c) 2011-2015, ARM Limited. All rights reserved.
3//
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
8//
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.
11//
12//
13
14#include <AutoGen.h>
15#include <Chipset/ArmV7.h>
16
17  INCLUDE AsmMacroIoLib.inc
18
19  IMPORT  CEntryPoint
20  IMPORT  ArmPlatformIsPrimaryCore
21  IMPORT  ArmReadMpidr
22  IMPORT  ArmPlatformPeiBootAction
23  IMPORT  ArmPlatformStackSet
24  IMPORT  mSystemMemoryEnd
25
26  EXPORT  _ModuleEntryPoint
27
28  PRESERVE8
29  AREA    PrePiCoreEntryPoint, CODE, READONLY
30
31StartupAddr        DCD      CEntryPoint
32
33_ModuleEntryPoint
34  // Do early platform specific actions
35  bl    ArmPlatformPeiBootAction
36
37  // Get ID of this CPU in Multicore system
38  bl    ArmReadMpidr
39  // Keep a copy of the MpId register value
40  mov   r8, r0
41
42_SetSVCMode
43  // Enter SVC mode, Disable FIQ and IRQ
44  mov     r1, #(CPSR_MODE_SVC :OR: CPSR_IRQ :OR: CPSR_FIQ)
45  msr     CPSR_c, r1
46
47// Check if we can install the stack at the top of the System Memory or if we need
48// to install the stacks at the bottom of the Firmware Device (case the FD is located
49// at the top of the DRAM)
50_SystemMemoryEndInit
51  adrll r1, mSystemMemoryEnd
52  ldrd  r2, r3, [r1]
53  teq   r3, #0
54  moveq r1, r2
55  mvnne r1, #0
56
57_SetupStackPosition
58  // r1 = SystemMemoryTop
59
60  // Calculate Top of the Firmware Device
61  mov32 r2, FixedPcdGet32(PcdFdBaseAddress)
62  mov32 r3, FixedPcdGet32(PcdFdSize)
63  sub   r3, r3, #1
64  add   r3, r3, r2      // r3 = FdTop = PcdFdBaseAddress + PcdFdSize
65
66  // UEFI Memory Size (stacks are allocated in this region)
67  mov32 r4, FixedPcdGet32(PcdSystemMemoryUefiRegionSize)
68
69  //
70  // Reserve the memory for the UEFI region (contain stacks on its top)
71  //
72
73  // Calculate how much space there is between the top of the Firmware and the Top of the System Memory
74  subs  r0, r1, r3      // r0 = SystemMemoryTop - FdTop
75  bmi   _SetupStack     // Jump if negative (FdTop > SystemMemoryTop). Case when the PrePi is in XIP memory outside of the DRAM
76  cmp   r0, r4
77  bge   _SetupStack
78
79  // Case the top of stacks is the FdBaseAddress
80  mov   r1, r2
81
82_SetupStack
83  // r1 contains the top of the stack (and the UEFI Memory)
84
85  // Because the 'push' instruction is equivalent to 'stmdb' (decrement before), we need to increment
86  // one to the top of the stack. We check if incrementing one does not overflow (case of DRAM at the
87  // top of the memory space)
88  adds  r9, r1, #1
89  bcs   _SetupOverflowStack
90
91_SetupAlignedStack
92  mov   r1, r9
93  b     _GetBaseUefiMemory
94
95_SetupOverflowStack
96  // Case memory at the top of the address space. Ensure the top of the stack is EFI_PAGE_SIZE
97  // aligned (4KB)
98  mov32 r9, EFI_PAGE_MASK
99  and   r9, r9, r1
100  sub   r1, r1, r9
101
102_GetBaseUefiMemory
103  // Calculate the Base of the UEFI Memory
104  sub   r9, r1, r4
105
106_GetStackBase
107  // r1 = The top of the Mpcore Stacks
108  // Stack for the primary core = PrimaryCoreStack
109  mov32 r2, FixedPcdGet32(PcdCPUCorePrimaryStackSize)
110  sub   r10, r1, r2
111
112  // Stack for the secondary core = Number of Cores - 1
113  mov32 r1, (FixedPcdGet32(PcdCoreCount) - 1) * FixedPcdGet32(PcdCPUCoreSecondaryStackSize)
114  sub   r10, r10, r1
115
116  // r10 = The base of the MpCore Stacks (primary stack & secondary stacks)
117  mov   r0, r10
118  mov   r1, r8
119  //ArmPlatformStackSet(StackBase, MpId, PrimaryStackSize, SecondaryStackSize)
120  mov32 r2, FixedPcdGet32(PcdCPUCorePrimaryStackSize)
121  mov32 r3, FixedPcdGet32(PcdCPUCoreSecondaryStackSize)
122  bl    ArmPlatformStackSet
123
124  // Is it the Primary Core ?
125  mov   r0, r8
126  bl    ArmPlatformIsPrimaryCore
127  cmp   r0, #1
128  bne   _PrepareArguments
129
130_PrepareArguments
131  mov   r0, r8
132  mov   r1, r9
133  mov   r2, r10
134
135  // Move sec startup address into a data register
136  // Ensure we're jumping to FV version of the code (not boot remapped alias)
137  ldr   r4, StartupAddr
138
139  // Jump to PrePiCore C code
140  //    r0 = MpId
141  //    r1 = UefiMemoryBase
142  //    r2 = StacksBase
143  blx   r4
144
145_NeverReturn
146  b _NeverReturn
147
148  END
149