Re: [PATCH V2 1/2] MdeModulePkg/CapsuleRuntimeDxe: IA32 add cache flush function

["Gao, Liming" <liming.gao@intel.com>]

Zhichao:
  Could you help clarify the commit message? Does IA32 and X64 Arch implementation need flush function or not? 

>The IA32 ARCH need cache flush function during capsule update.
>Both arm ARCH and IA32 do not need flush cache function,

Thanks
Liming
>-----Original Message-----
>From: Gao, Zhichao
>Sent: Friday, March 22, 2019 11:07 AM
>To: edk2-devel@lists.01.org
>Cc: Wang, Jian J <jian.j.wang@intel.com>; Wu, Hao A <hao.a.wu@intel.com>;
>Ni, Ray <ray.ni@intel.com>; Zeng, Star <star.zeng@intel.com>; Gao, Liming
><liming.gao@intel.com>; Ard Biesheuvel <ard.biesheuvel@linaro.org>
>Subject: [PATCH V2 1/2] MdeModulePkg/CapsuleRuntimeDxe: IA32 add cache
>flush function
>
>BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=1462
>
>The IA32 ARCH need cache flush function during capsule update.
>Both arm ARCH and IA32 do not need flush cache function, so
>merge the CapsuleCacheWriteBack() to one file. And add a null
>version for EBC.
>
>Contributed-under: TianoCore Contribution Agreement 1.1
>Signed-off-by: Zhichao Gao <zhichao.gao@intel.com>
>Cc: Jian J Wang <jian.j.wang@intel.com>
>Cc: Hao Wu <hao.a.wu@intel.com>
>Cc: Ray Ni <ray.ni@intel.com>
>Cc: Star Zeng <star.zeng@intel.com>
>Cc: Liming Gao <liming.gao@intel.com>
>Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
>---
> .../Universal/CapsuleRuntimeDxe/Arm/CapsuleReset.c | 35 +-----------
> .../Universal/CapsuleRuntimeDxe/CapsuleCache.c     | 63
>++++++++++++++++++++++
> .../Universal/CapsuleRuntimeDxe/CapsuleCacheNull.c | 38 +++++++++++++
> .../Universal/CapsuleRuntimeDxe/CapsuleReset.c     | 16 +-----
> .../CapsuleRuntimeDxe/CapsuleRuntimeDxe.inf        | 20 ++++---
> 5 files changed, 115 insertions(+), 57 deletions(-)
> create mode 100644
>MdeModulePkg/Universal/CapsuleRuntimeDxe/CapsuleCache.c
> create mode 100644
>MdeModulePkg/Universal/CapsuleRuntimeDxe/CapsuleCacheNull.c
>
>diff --git
>a/MdeModulePkg/Universal/CapsuleRuntimeDxe/Arm/CapsuleReset.c
>b/MdeModulePkg/Universal/CapsuleRuntimeDxe/Arm/CapsuleReset.c
>index d79d2fc693..ec630ab7a8 100644
>--- a/MdeModulePkg/Universal/CapsuleRuntimeDxe/Arm/CapsuleReset.c
>+++ b/MdeModulePkg/Universal/CapsuleRuntimeDxe/Arm/CapsuleReset.c
>@@ -3,6 +3,7 @@
>   PersistAcrossReset capsules
>
>   Copyright (c) 2018, Linaro, Ltd. All rights reserved.<BR>
>+  Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
>
>   This program and the accompanying materials are licensed and made
>available
>   under the terms and conditions of the BSD License which accompanies this
>@@ -16,8 +17,6 @@
>
> #include "CapsuleService.h"
>
>-#include <Library/CacheMaintenanceLib.h>
>-
> /**
>   Whether the platform supports capsules that persist across reset. Note that
>   some platforms only support such capsules at boot time.
>@@ -41,35 +40,3 @@ IsPersistAcrossResetCapsuleSupported (
>   return FeaturePcdGet (PcdSupportUpdateCapsuleReset) && !EfiAtRuntime
>();
> }
>
>-/**
>-  Writes Back a range of data cache lines covering a set of capsules in memory.
>-
>-  Writes Back the data cache lines specified by ScatterGatherList.
>-
>-  @param  ScatterGatherList Physical address of the data structure that
>-                            describes a set of capsules in memory
>-
>-**/
>-VOID
>-CapsuleCacheWriteBack (
>-  IN  EFI_PHYSICAL_ADDRESS    ScatterGatherList
>-  )
>-{
>-  EFI_CAPSULE_BLOCK_DESCRIPTOR    *Desc;
>-
>-  Desc = (EFI_CAPSULE_BLOCK_DESCRIPTOR *)(UINTN)ScatterGatherList;
>-  do {
>-    WriteBackDataCacheRange (Desc, sizeof *Desc);
>-
>-    if (Desc->Length > 0) {
>-      WriteBackDataCacheRange ((VOID *)(UINTN)Desc->Union.DataBlock,
>-                               Desc->Length
>-                               );
>-      Desc++;
>-    } else if (Desc->Union.ContinuationPointer > 0) {
>-      Desc = (EFI_CAPSULE_BLOCK_DESCRIPTOR *)(UINTN)Desc-
>>Union.ContinuationPointer;
>-    }
>-  } while (Desc->Length > 0 || Desc->Union.ContinuationPointer > 0);
>-
>-  WriteBackDataCacheRange (Desc, sizeof *Desc);
>-}
>diff --git a/MdeModulePkg/Universal/CapsuleRuntimeDxe/CapsuleCache.c
>b/MdeModulePkg/Universal/CapsuleRuntimeDxe/CapsuleCache.c
>new file mode 100644
>index 0000000000..ab81296a65
>--- /dev/null
>+++ b/MdeModulePkg/Universal/CapsuleRuntimeDxe/CapsuleCache.c
>@@ -0,0 +1,63 @@
>+/** @file
>+  Flush the cache is required for most architectures while do capsule
>+  update. It is not support at Runtime.
>+
>+  Copyright (c) 2018, Linaro, Ltd. All rights reserved.<BR>
>+  Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
>+
>+  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 "CapsuleService.h"
>+
>+#include <Library/CacheMaintenanceLib.h>
>+
>+/**
>+  Writes Back a range of data cache lines covering a set of capsules in memory.
>+
>+  Writes Back the data cache lines specified by ScatterGatherList.
>+
>+  @param  ScatterGatherList Physical address of the data structure that
>+                            describes a set of capsules in memory
>+
>+**/
>+VOID
>+CapsuleCacheWriteBack (
>+  IN  EFI_PHYSICAL_ADDRESS    ScatterGatherList
>+  )
>+{
>+  EFI_CAPSULE_BLOCK_DESCRIPTOR    *Desc;
>+
>+  if (!EfiAtRuntime ()) {
>+    Desc = (EFI_CAPSULE_BLOCK_DESCRIPTOR *)(UINTN)ScatterGatherList;
>+    do {
>+      WriteBackDataCacheRange (
>+        (VOID *)(UINTN)Desc,
>+        (UINTN)sizeof (*Desc)
>+        );
>+
>+      if (Desc->Length > 0) {
>+        WriteBackDataCacheRange (
>+          (VOID *)(UINTN)Desc->Union.DataBlock,
>+          (UINTN)Desc->Length
>+          );
>+        Desc++;
>+      } else if (Desc->Union.ContinuationPointer > 0) {
>+        Desc = (EFI_CAPSULE_BLOCK_DESCRIPTOR *)(UINTN)Desc-
>>Union.ContinuationPointer;
>+      }
>+    } while (Desc->Length > 0 || Desc->Union.ContinuationPointer > 0);
>+
>+    WriteBackDataCacheRange (
>+      (VOID *)(UINTN)Desc,
>+      (UINTN)sizeof (*Desc)
>+      );
>+  }
>+}
>+
>diff --git
>a/MdeModulePkg/Universal/CapsuleRuntimeDxe/CapsuleCacheNull.c
>b/MdeModulePkg/Universal/CapsuleRuntimeDxe/CapsuleCacheNull.c
>new file mode 100644
>index 0000000000..cfb9bb1bf1
>--- /dev/null
>+++ b/MdeModulePkg/Universal/CapsuleRuntimeDxe/CapsuleCacheNull.c
>@@ -0,0 +1,38 @@
>+/** @file
>+  Null function version of cache function.
>+
>+  Copyright (c) 2018, Linaro, Ltd. All rights reserved.<BR>
>+  Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
>+
>+  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 "CapsuleService.h"
>+
>+#include <Library/CacheMaintenanceLib.h>
>+
>+/**
>+  Writes Back a range of data cache lines covering a set of capsules in memory.
>+
>+  Writes Back the data cache lines specified by ScatterGatherList.
>+
>+  Null version, do nothing.
>+
>+  @param  ScatterGatherList Physical address of the data structure that
>+                            describes a set of capsules in memory
>+
>+**/
>+VOID
>+CapsuleCacheWriteBack (
>+  IN  EFI_PHYSICAL_ADDRESS    ScatterGatherList
>+  )
>+{
>+}
>+
>diff --git a/MdeModulePkg/Universal/CapsuleRuntimeDxe/CapsuleReset.c
>b/MdeModulePkg/Universal/CapsuleRuntimeDxe/CapsuleReset.c
>index 353f6f2090..8990cf2a35 100644
>--- a/MdeModulePkg/Universal/CapsuleRuntimeDxe/CapsuleReset.c
>+++ b/MdeModulePkg/Universal/CapsuleRuntimeDxe/CapsuleReset.c
>@@ -3,6 +3,7 @@
>   PersistAcrossReset capsules
>
>   Copyright (c) 2018, Linaro, Ltd. All rights reserved.<BR>
>+  Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
>
>   This program and the accompanying materials are licensed and made
>available
>   under the terms and conditions of the BSD License which accompanies this
>@@ -32,18 +33,3 @@ IsPersistAcrossResetCapsuleSupported (
>   return FeaturePcdGet (PcdSupportUpdateCapsuleReset);
> }
>
>-/**
>-  Writes Back a range of data cache lines covering a set of capsules in memory.
>-
>-  Writes Back the data cache lines specified by ScatterGatherList.
>-
>-  @param  ScatterGatherList Physical address of the data structure that
>-                            describes a set of capsules in memory
>-
>-**/
>-VOID
>-CapsuleCacheWriteBack (
>-  IN  EFI_PHYSICAL_ADDRESS    ScatterGatherList
>-  )
>-{
>-}
>diff --git
>a/MdeModulePkg/Universal/CapsuleRuntimeDxe/CapsuleRuntimeDxe.inf
>b/MdeModulePkg/Universal/CapsuleRuntimeDxe/CapsuleRuntimeDxe.inf
>index ad7af5fe62..a0cb32a06f 100644
>--- a/MdeModulePkg/Universal/CapsuleRuntimeDxe/CapsuleRuntimeDxe.inf
>+++
>b/MdeModulePkg/Universal/CapsuleRuntimeDxe/CapsuleRuntimeDxe.inf
>@@ -4,7 +4,7 @@
> #  It installs the Capsule Architectural Protocol defined in PI1.0a to signify
> #  the capsule runtime services are ready.
> #
>-#  Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
>+#  Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
> #  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
>@@ -36,16 +36,22 @@
>
> [Sources.Ia32, Sources.EBC, Sources.ARM, Sources.AARCH64]
>   SaveLongModeContext.c
>-  CapsuleReset.c
>
>-[Sources.X64]
>-  X64/SaveLongModeContext.c
>+[Sources.Ia32, Sources.X64, Sources.ARM, Sources.AARCH64]
>+  CapsuleCache.c
>+
>+[Sources.Ia32, Sources.X64, Sources.EBC]
>   CapsuleReset.c
>
> [Sources.ARM, Sources.AARCH64]
>-  SaveLongModeContext.c
>   Arm/CapsuleReset.c
>
>+[Sources.EBC]
>+  CapsuleCacheNull.c
>+
>+[Sources.X64]
>+  X64/SaveLongModeContext.c
>+
> [Packages]
>   MdePkg/MdePkg.dec
>   MdeModulePkg/MdeModulePkg.dec
>@@ -61,14 +67,12 @@
>   BaseLib
>   PrintLib
>   BaseMemoryLib
>+  CacheMaintenanceLib
>
> [LibraryClasses.X64]
>   UefiLib
>   BaseMemoryLib
>
>-[LibraryClasses.ARM, LibraryClasses.AARCH64]
>-  CacheMaintenanceLib
>-
> [Guids]
>   ## SOMETIMES_PRODUCES   ## Variable:L"CapsuleUpdateData" # (Process
>across reset capsule image) for capsule updated data
>   ## SOMETIMES_PRODUCES   ## Variable:L"CapsuleLongModeBuffer" # The
>long mode buffer used by IA32 Capsule PEIM to call X64 CapsuleCoalesce code
>to handle >4GB capsule blocks
>--
>2.16.2.windows.1