ArmVirtPkg/Library/ArmXenRelocatablePlatformLib/AARCH64/RelocatableVirtHelper.S

   1 #
   2 #  Copyright (c) 2011-2013, 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 <AsmMacroIoLibV8.h>
  15 #include <Base.h>
  16 #include <Library/ArmLib.h>
  17 #include <Library/PcdLib.h>
  18 #include <AutoGen.h>
  19
  20 .text
  21 .align 2
  22
  23 GCC_ASM_EXPORT(ArmPlatformPeiBootAction)
  24 GCC_ASM_EXPORT(ArmPlatformIsPrimaryCore)
  25 GCC_ASM_EXPORT(ArmPlatformGetPrimaryCoreMpId)
  26 GCC_ASM_EXPORT(ArmPlatformGetCorePosition)
  27 GCC_ASM_EXPORT(ArmGetPhysAddrTop)
  28
  29 GCC_ASM_IMPORT(_gPcd_FixedAtBuild_PcdArmPrimaryCore)
  30 GCC_ASM_IMPORT(_gPcd_FixedAtBuild_PcdArmPrimaryCoreMask)
  31 GCC_ASM_IMPORT(_gPcd_FixedAtBuild_PcdCoreCount)
  32
  33 .LArm64LinuxMagic:
  34   .byte   0x41, 0x52, 0x4d, 0x64
  35
  36 // VOID
  37 // ArmPlatformPeiBootAction (
  38 //   VOID   *DeviceTreeBaseAddress,   // passed by loader in x0
  39 //   VOID   *ImageBase                // passed by FDF trampoline in x1
  40 //   );
  41 ASM_PFX(ArmPlatformPeiBootAction):
  42   mov   x29, x30            // preserve LR
  43   mov   x28, x0             // preserve DTB pointer
  44   mov   x27, x1             // preserve base of image pointer
  45
  46   //
  47   // If we are booting from RAM using the Linux kernel boot protocol, x0 will
  48   // point to the DTB image in memory. Otherwise, we are just coming out of
  49   // reset, and x0 will be 0.
  50   //
  51   cbz   x0, .Lout
  52
  53   //
  54   // The base of the runtime image has been preserved in x1. Check whether
  55   // the expected magic number can be found in the header.
  56   //
  57   ldr   w8, .LArm64LinuxMagic
  58   ldr   w9, [x1, #0x38]
  59   cmp   w8, w9
  60   bne   .Lout
  61
  62   //
  63   //
  64   // OK, so far so good. We have confirmed that we likely have a DTB and are
  65   // booting via the arm64 Linux boot protocol. Update the base-of-image PCD
  66   // to the actual relocated value, and add the shift of PcdFdBaseAddress to
  67   // PcdFvBaseAddress as well
  68   //
  69   adr   x8, PcdGet64 (PcdFdBaseAddress)
  70   adr   x9, PcdGet64 (PcdFvBaseAddress)
  71   ldr   x6, [x8]
  72   ldr   x7, [x9]
  73   sub   x7, x7, x6
  74   add   x7, x7, x1
  75   str   x1, [x8]
  76   str   x7, [x9]
  77
  78   //
  79   // Discover the memory size and offset from the DTB, and record in the
  80   // respective PCDs. This will also return false if a corrupt DTB is
  81   // encountered. Since we are calling a C function, use the window at the
  82   // beginning of the FD image as a temp stack.
  83   //
  84   adr   x1, PcdGet64 (PcdSystemMemoryBase)
  85   adr   x2, PcdGet64 (PcdSystemMemorySize)
  86   mov   sp, x7
  87   bl    FindMemnode
  88   cbz   x0, .Lout
  89
  90   //
  91   // Copy the DTB to the slack space right after the 64 byte arm64/Linux style
  92   // image header at the base of this image (defined in the FDF), and record the
  93   // pointer in PcdDeviceTreeInitialBaseAddress.
  94   //
  95   adr   x8, PcdGet64 (PcdDeviceTreeInitialBaseAddress)
  96   add   x27, x27, #0x40
  97   str   x27, [x8]
  98
  99   mov   x0, x27
 100   mov   x1, x28
 101   bl    CopyFdt
 102
 103 .Lout:
 104   ret    x29
 105
 106 //UINTN
 107 //ArmPlatformGetPrimaryCoreMpId (
 108 //  VOID
 109 //  );
 110 ASM_PFX(ArmPlatformGetPrimaryCoreMpId):
 111   LoadConstantToReg (_gPcd_FixedAtBuild_PcdArmPrimaryCore, x0)
 112   ldrh   w0, [x0]
 113   ret
 114
 115 //UINTN
 116 //ArmPlatformIsPrimaryCore (
 117 //  IN UINTN MpId
 118 //  );
 119 ASM_PFX(ArmPlatformIsPrimaryCore):
 120   mov   x0, #1
 121   ret
 122
 123 //UINTN
 124 //ArmPlatformGetCorePosition (
 125 //  IN UINTN MpId
 126 //  );
 127 // With this function: CorePos = (ClusterId * 4) + CoreId
 128 ASM_PFX(ArmPlatformGetCorePosition):
 129   and   x1, x0, #ARM_CORE_MASK
 130   and   x0, x0, #ARM_CLUSTER_MASK
 131   add   x0, x1, x0, LSR #6
 132   ret
 133
 134 //EFI_PHYSICAL_ADDRESS
 135 //GetPhysAddrTop (
 136 //  VOID
 137 //  );
 138 ASM_PFX(ArmGetPhysAddrTop):
 139   mrs   x0, id_aa64mmfr0_el1
 140   adr   x1, .LPARanges
 141   and   x0, x0, #7
 142   ldrb  w1, [x1, x0]
 143   mov   x0, #1
 144   lsl   x0, x0, x1
 145   ret
 146
 147 //
 148 // Bits 0..2 of the AA64MFR0_EL1 system register encode the size of the
 149 // physical address space support on this CPU:
 150 // 0 == 32 bits, 1 == 36 bits, etc etc
 151 // 6 and 7 are reserved
 152 //
 153 .LPARanges:
 154   .byte 32, 36, 40, 42, 44, 48, -1, -1
 155
 156 ASM_FUNCTION_REMOVE_IF_UNREFERENCED