ArmPlatformPkg/PrePi/AArch64/ArchPrePi.c

   1 /** @file
   2 *
   3 *  Copyright (c) 2011-2017, ARM 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 "PrePi.h"
  16
  17 #include <Chipset/AArch64.h>
  18
  19 VOID
  20 ArchInitialize (
  21   VOID
  22   )
  23 {
  24   // Enable Floating Point
  25   if (FixedPcdGet32 (PcdVFPEnabled)) {
  26     ArmEnableVFP ();
  27   }
  28
  29   if (ArmReadCurrentEL () == AARCH64_EL2) {
  30     // Trap General Exceptions. All exceptions that would be routed to EL1 are routed to EL2
  31     ArmWriteHcr (ARM_HCR_TGE);
  32
  33     /* Enable Timer access for non-secure EL1 and EL0
  34        The cnthctl_el2 register bits are architecturally
  35        UNKNOWN on reset.
  36        Disable event stream as it is not in use at this stage
  37     */
  38     ArmWriteCntHctl (CNTHCTL_EL2_EL1PCTEN | CNTHCTL_EL2_EL1PCEN);
  39   }
  40 }