ArmVirtPkg/Library/XenVirtMemInfoLib/AArch64/PhysAddrTop.S

   1 #
   2 #  Copyright (c) 2011-2013, ARM Limited. All rights reserved.
   3 #  Copyright (c) 2016-2017, Linaro Limited. All rights reserved.
   4 #
   5 #  This program and the accompanying materials
   6 #  are licensed and made available under the terms and conditions of the BSD License
   7 #  which accompanies this distribution.  The full text of the license may be found at
   8 #  http://opensource.org/licenses/bsd-license.php
   9 #
  10 #  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11 #  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12 #
  13 #
  14
  15 #include <AsmMacroIoLibV8.h>
  16
  17 //EFI_PHYSICAL_ADDRESS
  18 //GetPhysAddrTop (
  19 //  VOID
  20 //  );
  21 ASM_FUNC(ArmGetPhysAddrTop)
  22   mrs   x0, id_aa64mmfr0_el1
  23   adr   x1, .LPARanges
  24   and   x0, x0, #7
  25   ldrb  w1, [x1, x0]
  26   mov   x0, #1
  27   lsl   x0, x0, x1
  28   ret
  29
  30 //
  31 // Bits 0..2 of the AA64MFR0_EL1 system register encode the size of the
  32 // physical address space support on this CPU:
  33 // 0 == 32 bits, 1 == 36 bits, etc etc
  34 // 6 and 7 are reserved
  35 //
  36 .LPARanges:
  37   .byte 32, 36, 40, 42, 44, 48, -1, -1
  38
  39 ASM_FUNCTION_REMOVE_IF_UNREFERENCED