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-rw-r--r--ArmPlatformPkg/PrePeiCore/AArch64/PrePeiCoreEntryPoint.S114
1 files changed, 114 insertions, 0 deletions
diff --git a/ArmPlatformPkg/PrePeiCore/AArch64/PrePeiCoreEntryPoint.S b/ArmPlatformPkg/PrePeiCore/AArch64/PrePeiCoreEntryPoint.S
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index 0000000000..5bdbe4585f
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+++ b/ArmPlatformPkg/PrePeiCore/AArch64/PrePeiCoreEntryPoint.S
@@ -0,0 +1,114 @@
+//
+// Copyright (c) 2011-2013, ARM Limited. All rights reserved.
+//
+// This program and the accompanying materials
+// are licensed and made available under the terms and conditions of the BSD License
+// which accompanies this distribution. The full text of the license may be found at
+// http://opensource.org/licenses/bsd-license.php
+//
+// THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+// WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+//
+//
+
+#include <AsmMacroIoLibV8.h>
+#include <Base.h>
+#include <Library/PcdLib.h>
+#include <AutoGen.h>
+
+.text
+.align 3
+
+GCC_ASM_IMPORT(CEntryPoint)
+GCC_ASM_IMPORT(ArmPlatformGetCorePosition)
+GCC_ASM_IMPORT(ArmPlatformIsPrimaryCore)
+GCC_ASM_IMPORT(ArmReadMpidr)
+GCC_ASM_IMPORT(ArmPlatformPeiBootAction)
+GCC_ASM_EXPORT(_ModuleEntryPoint)
+
+StartupAddr: .dword CEntryPoint
+
+ASM_PFX(_ModuleEntryPoint):
+ // Do early platform specific actions
+ bl ASM_PFX(ArmPlatformPeiBootAction)
+
+// NOTE: We could be booting from EL3, EL2 or EL1. Need to correctly detect
+// and configure the system accordingly. EL2 is default if possible.
+// If we started in EL3 we need to switch and run at EL2.
+// If we are running at EL2 stay in EL2
+// If we are starting at EL1 stay in EL1.
+
+// If started at EL3 Sec is run and switches to EL2 before jumping to PEI.
+// If started at EL1 or EL2 Sec jumps directly to PEI without making any
+// changes.
+
+// Which EL are we running at? Every EL needs some level of setup...
+ EL1_OR_EL2_OR_EL3(x0)
+1:bl ASM_PFX(SetupExceptionLevel1)
+ b ASM_PFX(MainEntryPoint)
+2:bl ASM_PFX(SetupExceptionLevel2)
+ b ASM_PFX(MainEntryPoint)
+3:// If we are at EL3 we die.
+ b dead
+
+ASM_PFX(MainEntryPoint):
+ // Identify CPU ID
+ bl ASM_PFX(ArmReadMpidr)
+ // Keep a copy of the MpId register value
+ mov x5, x0
+
+ // Is it the Primary Core ?
+ bl ASM_PFX(ArmPlatformIsPrimaryCore)
+
+ // Get the top of the primary stacks (and the base of the secondary stacks)
+ LoadConstantToReg (FixedPcdGet32(PcdCPUCoresStackBase), x1)
+ LoadConstantToReg (FixedPcdGet32(PcdCPUCorePrimaryStackSize), x2)
+ add x1, x1, x2
+
+ // x0 is equal to 1 if I am the primary core
+ cmp x0, #1
+ b.eq _SetupPrimaryCoreStack
+
+_SetupSecondaryCoreStack:
+ // x1 contains the base of the secondary stacks
+
+ // Get the Core Position
+ mov x6, x1 // Save base of the secondary stacks
+ mov x0, x5
+ bl ASM_PFX(ArmPlatformGetCorePosition)
+ // The stack starts at the top of the stack region. Add '1' to the Core Position to get the top of the stack
+ add x0, x0, #1
+
+ // StackOffset = CorePos * StackSize
+ LoadConstantToReg (FixedPcdGet32(PcdCPUCoreSecondaryStackSize), x2)
+ mul x0, x0, x2
+ // SP = StackBase + StackOffset
+ add sp, x6, x0
+
+_PrepareArguments:
+ // The PEI Core Entry Point has been computed by GenFV and stored in the second entry of the Reset Vector
+ LoadConstantToReg (FixedPcdGet64(PcdFvBaseAddress), x2)
+ add x2, x2, #8
+ ldr x1, [x2]
+
+ // Move sec startup address into a data register
+ // Ensure we're jumping to FV version of the code (not boot remapped alias)
+ ldr x3, StartupAddr
+
+ // Jump to PrePeiCore C code
+ // x0 = mp_id
+ // x1 = pei_core_address
+ mov x0, x5
+ blr x3
+
+_SetupPrimaryCoreStack:
+ // x1 contains the top of the primary stack
+ LoadConstantToReg (FixedPcdGet32(PcdPeiGlobalVariableSize), x2)
+
+ // The reserved space for global variable must be 16-bytes aligned for pushing
+ // 128-bit variable on the stack
+ SetPrimaryStack (x1, x2, x3, x4)
+ b _PrepareArguments
+
+dead:
+ b dead