[PATCH v2 3/3] MdeModulePkg/DxeIplPeim : RISC-V platform level DxeIPL

["Abner Chang" <abner.chang@hpe.com>]

Implementation of RISC-V DxeIPL.

Signed-off-by: Abner Chang <abner.chang@hpe.com>
Co-authored-by: Gilbert Chen <gilbert.chen@hpe.com>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>

Cc: Dandan Bi <dandan.bi@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Gilbert Chen <gilbert.chen@hpe.com>
---
 MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf       |  6 +-
 .../Core/DxeIplPeim/RiscV64/DxeLoadFunc.c     | 74 +++++++++++++++++++
 2 files changed, 79 insertions(+), 1 deletion(-)
 create mode 100644 MdeModulePkg/Core/DxeIplPeim/RiscV64/DxeLoadFunc.c

diff --git a/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf b/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf
index 98bc17fc9d..3f17028546 100644
--- a/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf
+++ b/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf
@@ -7,6 +7,7 @@
 #
 #  Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
 #  Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR>
+#  Copyright (c) 2020, Hewlett Packard Enterprise Development LP. All rights reserved.<BR>
 #
 #  SPDX-License-Identifier: BSD-2-Clause-Patent
 #
@@ -25,7 +26,7 @@
 #
 # The following information is for reference only and not required by the build tools.
 #
-#  VALID_ARCHITECTURES           = IA32 X64 EBC (EBC is for build only) AARCH64
+#  VALID_ARCHITECTURES           = IA32 X64 EBC (EBC is for build only) AARCH64 RISCV64
 #
 
 [Sources]
@@ -49,6 +50,9 @@
 [Sources.ARM, Sources.AARCH64]
   Arm/DxeLoadFunc.c
 
+[Sources.RISCV64]
+  RiscV64/DxeLoadFunc.c
+
 [Packages]
   MdePkg/MdePkg.dec
   MdeModulePkg/MdeModulePkg.dec
diff --git a/MdeModulePkg/Core/DxeIplPeim/RiscV64/DxeLoadFunc.c b/MdeModulePkg/Core/DxeIplPeim/RiscV64/DxeLoadFunc.c
new file mode 100644
index 0000000000..2ce52eb0ec
--- /dev/null
+++ b/MdeModulePkg/Core/DxeIplPeim/RiscV64/DxeLoadFunc.c
@@ -0,0 +1,74 @@
+/** @file
+  RISC-V specific functionality for DxeLoad.
+
+  Copyright (c) 2020, Hewlett Packard Enterprise Development LP. All rights reserved.<BR>
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include "DxeIpl.h"
+
+/**
+   Transfers control to DxeCore.
+
+   This function performs a CPU architecture specific operations to execute
+   the entry point of DxeCore with the parameters of HobList.
+   It also installs EFI_END_OF_PEI_PPI to signal the end of PEI phase.
+
+   @param DxeCoreEntryPoint         The entry point of DxeCore.
+   @param HobList                   The start of HobList passed to DxeCore.
+
+**/
+VOID
+HandOffToDxeCore (
+  IN EFI_PHYSICAL_ADDRESS   DxeCoreEntryPoint,
+  IN EFI_PEI_HOB_POINTERS   HobList
+  )
+{
+  VOID                            *BaseOfStack;
+  VOID                            *TopOfStack;
+  EFI_STATUS                      Status;
+  //
+  //
+  // Allocate 128KB for the Stack
+  //
+  BaseOfStack = AllocatePages (EFI_SIZE_TO_PAGES (STACK_SIZE));
+  if (BaseOfStack == NULL) {
+    DEBUG((DEBUG_ERROR, "%a: Can't allocate memory for stack.", __FUNCTION__));
+    ASSERT(FALSE);
+  }
+
+  //
+  // Compute the top of the stack we were allocated. Pre-allocate a UINTN
+  // for safety.
+  //
+  TopOfStack = (VOID *)((UINTN) BaseOfStack + EFI_SIZE_TO_PAGES (STACK_SIZE) * EFI_PAGE_SIZE - CPU_STACK_ALIGNMENT);
+  TopOfStack = ALIGN_POINTER (TopOfStack, CPU_STACK_ALIGNMENT);
+
+  //
+  // End of PEI phase signal
+  //
+  Status = PeiServicesInstallPpi (&gEndOfPeiSignalPpi);
+  if (EFI_ERROR (Status)) {
+    DEBUG((DEBUG_ERROR, "%a: Fail to signal End of PEI event.", __FUNCTION__));
+    ASSERT(FALSE);
+  }
+  //
+  // Update the contents of BSP stack HOB to reflect the real stack info passed to DxeCore.
+  //
+  UpdateStackHob ((EFI_PHYSICAL_ADDRESS)(UINTN) BaseOfStack, STACK_SIZE);
+
+  DEBUG ((DEBUG_INFO, "DXE Core new stack at %x, stack pointer at %x\n", BaseOfStack, TopOfStack));
+
+  //
+  // Transfer the control to the entry point of DxeCore.
+  //
+  SwitchStack (
+    (SWITCH_STACK_ENTRY_POINT)(UINTN)DxeCoreEntryPoint,
+    HobList.Raw,
+    NULL,
+    TopOfStack
+    );
+}
+
-- 
2.25.0