From 3fc05b04735d40429ff3953810b1df76918e97f4 Mon Sep 17 00:00:00 2001
From: Mikhail Krichanov <mikhailkrichanov@gmail.com>
Date: Mon, 20 May 2024 17:27:09 +0300
Subject: [PATCH] Ring3: Defined CallRing3() for AARCH64.
---
.../AArch64/DefaultExceptionHandler.c | 4 +++
MdeModulePkg/Core/Dxe/DxeMain.h | 2 ++
.../Core/Dxe/DxeRing3/AARCH64/SysCall.S | 8 ++---
.../Dxe/SysCall/AARCH64/CoreBootServices.S | 36 +++++++++++++++++--
.../Core/Dxe/SysCall/AARCH64/InitializeMsr.c | 17 +++++++++
5 files changed, 60 insertions(+), 7 deletions(-)
diff --git a/ArmPkg/Library/DefaultExceptionHandlerLib/AArch64/DefaultExceptionHandler.c b/ArmPkg/Library/DefaultExceptionHandlerLib/AArch64/DefaultExceptionHandler.c
index 65e9a81e2d..7e5460aa58 100644
--- a/ArmPkg/Library/DefaultExceptionHandlerLib/AArch64/DefaultExceptionHandler.c
+++ b/ArmPkg/Library/DefaultExceptionHandlerLib/AArch64/DefaultExceptionHandler.c
@@ -8,6 +8,8 @@
**/
+#include <Chipset/AArch64.h>
+
#include <Uefi.h>
#include <Library/UefiLib.h>
#include <Library/BaseLib.h>
@@ -233,6 +235,8 @@ DefaultExceptionHandler (
DEBUG ((DEBUG_ERROR, "PC 0x%012lx\n", SystemContext.SystemContextAArch64->ELR));
}
+ ArmClearPan ();
+
if ((UINT64 *)SystemContext.SystemContextAArch64->FP != 0) {
Idx = 0;
diff --git a/MdeModulePkg/Core/Dxe/DxeMain.h b/MdeModulePkg/Core/Dxe/DxeMain.h
index 2a78eb063d..f50bf3de02 100644
--- a/MdeModulePkg/Core/Dxe/DxeMain.h
+++ b/MdeModulePkg/Core/Dxe/DxeMain.h
@@ -276,6 +276,8 @@ extern VOID *gRing3Interfaces;
extern VOID *gCoreSysCallStackBase;
extern VOID *gCoreSysCallStackTop;
extern VOID *gRing3CallStackBase;
+extern VOID *gRing3CallStackTop;
+extern VOID *gRing3EntryPoint;
//
// Service Initialization Functions
diff --git a/MdeModulePkg/Core/Dxe/DxeRing3/AARCH64/SysCall.S b/MdeModulePkg/Core/Dxe/DxeRing3/AARCH64/SysCall.S
index 2a22be0c0a..8678dacbfe 100644
--- a/MdeModulePkg/Core/Dxe/DxeRing3/AARCH64/SysCall.S
+++ b/MdeModulePkg/Core/Dxe/DxeRing3/AARCH64/SysCall.S
@@ -5,6 +5,8 @@
#include <AsmMacroIoLibV8.h>
+.extern ASM_PFX(Ring3Call)
+
//------------------------------------------------------------------------------
// EFI_STATUS
// EFIAPI
@@ -24,9 +26,7 @@ ASM_FUNC(SysCall)
// IN RING3_CALL_DATA *Data
// );
//
-// (rcx) RIP of Ring3EntryPoint saved for SYSRET in CallRing3().
-// (rdx) Data
+// (x0) Data
//------------------------------------------------------------------------------
ASM_FUNC(Ring3EntryPoint)
-
- ret
+ b ASM_PFX(Ring3Call)
diff --git a/MdeModulePkg/Core/Dxe/SysCall/AARCH64/CoreBootServices.S b/MdeModulePkg/Core/Dxe/SysCall/AARCH64/CoreBootServices.S
index 35e0c3f6c9..06d28f0c3e 100644
--- a/MdeModulePkg/Core/Dxe/SysCall/AARCH64/CoreBootServices.S
+++ b/MdeModulePkg/Core/Dxe/SysCall/AARCH64/CoreBootServices.S
@@ -47,7 +47,37 @@ ASM_FUNC(CoreBootServices)
// IN RING3_CALL_DATA *Data
// );
//
-// (rcx) Data
+// (x0) Data
+// (x1) gRing3CallStackTop
+// (x2) gRing3EntryPoint
//------------------------------------------------------------------------------
-ASM_FUNC(CallRing3)
- ret
+ASM_FUNC(ArmCallRing3)
+ // Disable interrupts
+ msr daifset, #0xf
+ isb
+
+ // Use SP_ELx for Exception level ELx.
+ msr SPsel, #1
+
+ msr sp_el0, x1
+
+ msr elr_el1, x2
+
+ // Copy PSTATE to SPSR.
+ mrs x1, nzcv
+ mrs x2, pan
+ orr x1, x1, x2
+ mrs x2, daif
+ orr x1, x1, x2
+ //
+ // M[3:0], bits [3:0] AArch64 Exception level and selected Stack Pointer.
+ // 0b0000 - EL0.
+ // 0b0100 - EL1 with SP_EL0 (ELt).
+ // 0b0101 - EL1 with SP_EL1 (EL1h).
+ //
+ msr spsr_el1, x1
+
+ isb
+ dsb sy
+
+ eret
diff --git a/MdeModulePkg/Core/Dxe/SysCall/AARCH64/InitializeMsr.c b/MdeModulePkg/Core/Dxe/SysCall/AARCH64/InitializeMsr.c
index 470773a19a..0510fc5957 100644
--- a/MdeModulePkg/Core/Dxe/SysCall/AARCH64/InitializeMsr.c
+++ b/MdeModulePkg/Core/Dxe/SysCall/AARCH64/InitializeMsr.c
@@ -10,6 +10,14 @@
#include "DxeMain.h"
+EFI_STATUS
+EFIAPI
+ArmCallRing3 (
+ IN RING3_CALL_DATA *Data,
+ IN VOID *StackPointer,
+ IN VOID *EntryPoint
+ );
+
VOID
EFIAPI
InitializeMsr (
@@ -59,3 +67,12 @@ EnableSMAP (
{
ArmSetPan ();
}
+
+EFI_STATUS
+EFIAPI
+CallRing3 (
+ IN RING3_CALL_DATA *Data
+ )
+{
+ return ArmCallRing3 (Data, gRing3CallStackTop, gRing3EntryPoint);
+}