ArmPlatformPkg/ArmVExpressPkg/Library/ArmVExpressSecLibRTSM/Arm/RTSMHelper.asm

   1 //
   2 //  Copyright (c) 2011-2012, 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 <AsmMacroIoLib.h>
  15 #include <Base.h>
  16 #include <Library/PcdLib.h>
  17
  18 #include <Chipset/ArmCortexA9.h>
  19
  20 #include <AutoGen.h>
  21
  22   INCLUDE AsmMacroIoLib.inc
  23
  24   EXPORT    ArmGetCpuCountPerCluster
  25
  26   AREA RTSMHelper, CODE, READONLY
  27
  28 // IN None
  29 // OUT r0 = SCU Base Address
  30 ArmGetScuBaseAddress
  31   // Read Configuration Base Address Register. ArmCBar cannot be called to get
  32   // the Configuration BAR as a stack is not necessary setup. The SCU is at the
  33   // offset 0x0000 from the Private Memory Region.
  34   mrc   p15, 4, r0, c15, c0, 0
  35   bx  lr
  36
  37 // IN None
  38 // OUT r0 = number of cores present in the system
  39 ArmGetCpuCountPerCluster
  40   stmfd SP!, {r1-r2}
  41
  42   // Read CP15 MIDR
  43   mrc   p15, 0, r1, c0, c0, 0
  44
  45   // Check if the CPU is A15
  46   mov   r1, r1, LSR #4
  47   mov   r0, #ARM_CPU_TYPE_MASK
  48   and   r1, r1, r0
  49
  50   mov   r0, #ARM_CPU_TYPE_A15
  51   cmp   r1, r0
  52   beq   _Read_cp15_reg
  53
  54 _CPU_is_not_A15
  55   mov   r2, lr                              ; Save link register
  56   bl    ArmGetScuBaseAddress                ; Read SCU Base Address
  57   mov   lr, r2                              ; Restore link register val
  58   ldr   r0, [r0, #A9_SCU_CONFIG_OFFSET]     ; Read SCU Config reg to get CPU count
  59   b     _Return
  60
  61 _Read_cp15_reg
  62   mrc   p15, 1, r0, c9, c0, 2            ; Read C9 register of CP15 to get CPU count
  63   lsr   r0, #24
  64
  65
  66 _Return
  67   and   r0, r0, #3
  68   // Add '1' to the number of CPU on the Cluster
  69   add   r0, r0, #1
  70   ldmfd SP!, {r1-r2}
  71   bx lr
  72
  73   END