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[edk2-devel] [edk2-platforms PATCH 2/7] LoongArchQemuPkg/LsRealTimeClockLib: remove superfluous instance init steps

Laszlo Ersek posted 7 patches 2 years, 3 months ago
[edk2-devel] [edk2-platforms PATCH 2/7] LoongArchQemuPkg/LsRealTimeClockLib: remove superfluous instance init steps
Posted by Laszlo Ersek 2 years, 3 months ago 
RealTimeClockLib instances are consumed by edk2's
EmbeddedPkg/RealTimeClockRuntimeDxe driver. In its entry point function
InitializeRealTimeClock(), the driver:

(1) calls LibRtcInitialize(),

(2) sets the GetTime(), SetTime(), GetWakeupTime() and SetWakeupTime()
    runtime services to its own similarly-named functions -- where those
    functions wrap the corresponding RealTimeClockLib APIs,

(3) installs EFI_REAL_TIME_CLOCK_ARCH_PROTOCOL with a NULL protocol
    interface.

Steps (2) and (3) conform to PI v1.8 sections II-9.7.2.4 through
II-9.7.2.7.

However, this means that LibRtcInitialize() (of any RealTimeClockLib
instance) should not itself (a) set the GetTime(), SetTime(),
GetWakeupTime() and SetWakeupTime() runtime services, nor (b) install
EFI_REAL_TIME_CLOCK_ARCH_PROTOCOL. The runtime service pointers will be
overwritten in step (2) anyway, and step (3) will uselessly install a
second (NULL-interface) EFI_REAL_TIME_CLOCK_ARCH_PROTOCOL instance in the
protocol database. (The protocol only serves to notify the DXE Foundation
about said runtime services being available.)

Clean up LoongArchQemuPkg/LsRealTimeClockLib accordingly.

(Note that the lib instance INF file already does not list
UefiRuntimeServicesTableLib.)

Build-tested only (with "Loongson.dsc").

Cc: Bibo Mao <maobibo@loongson.cn>
Cc: Chao Li <lichao@loongson.cn>
Cc: Xianglai li <lixianglai@loongson.cn>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=4565
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
---

Notes:
    context:-W

 Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.inf |  3 ---
 Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.c   | 16 ----------------
 2 files changed, 19 deletions(-)

diff --git a/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.inf b/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.inf
index 5aa95650f8ba..c5ab1a702167 100644
--- a/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.inf
+++ b/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.inf
@@ -40,8 +40,5 @@ [Pcd]
 [Guids]
   gEfiEventVirtualAddressChangeGuid
 
-[Protocols]
-  gEfiRealTimeClockArchProtocolGuid             # PROTOCOL ALWAYS_PRODUCED
-
 [Depex]
   TRUE
diff --git a/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.c b/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.c
index eeac011a9400..954589ecb328 100644
--- a/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.c
+++ b/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.c
@@ -1,30 +1,28 @@
 /** @file
   Implement EFI RealTimeClock runtime services via RTC Lib.
 
   Copyright (c) 2022, Loongson Limited. All rights reserved.
 
   SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
 #include <Uefi.h>
 #include <PiDxe.h>
 
 #include <Guid/EventGroup.h>
 #include <Guid/GlobalVariable.h>
 
 #include <Library/BaseLib.h>
 #include <Library/DebugLib.h>
 #include <Library/DxeServicesTableLib.h>
 #include <Library/IoLib.h>
 #include <Library/MemoryAllocationLib.h>
 #include <Library/PcdLib.h>
 #include <Library/RealTimeClockLib.h>
 #include <Library/TimeBaseLib.h>
 #include <Library/UefiBootServicesTableLib.h>
-#include <Library/UefiRuntimeServicesTableLib.h>
 #include <Library/UefiRuntimeLib.h>
-#include <Protocol/RealTimeClock.h>
 #include "LsRealTimeClock.h"
 
 STATIC BOOLEAN                mInitialized = FALSE;
@@ -291,46 +289,32 @@ EFIAPI
 LibRtcInitialize (
   IN EFI_HANDLE                            ImageHandle,
   IN EFI_SYSTEM_TABLE                      *SystemTable
   )
 {
   EFI_STATUS    Status;
-  EFI_HANDLE    Handle;
 
   InitRtc ();
   Status = KvmtoolRtcMapMemory (ImageHandle, (mRtcBase & ~EFI_PAGE_MASK));
   if (EFI_ERROR (Status)) {
     DEBUG ((
       DEBUG_ERROR,
       "Failed to map memory for loongson 7A RTC. Status = %r\n",
       Status
       ));
     return Status;
   }
 
-  // Setup the setters and getters
-  gRT->GetTime       = LibGetTime;
-  gRT->SetTime       = LibSetTime;
-
-  // Install the protocol
-  Handle = NULL;
-  Status = gBS->InstallMultipleProtocolInterfaces (
-                  &Handle,
-                  &gEfiRealTimeClockArchProtocolGuid,  NULL,
-                  NULL
-                 );
-  ASSERT_EFI_ERROR (Status);
-
   //
   // Register for the virtual address change event
   //
   Status = gBS->CreateEventEx (
                   EVT_NOTIFY_SIGNAL,
                   TPL_NOTIFY,
                   VirtualNotifyEvent,
                   NULL,
                   &gEfiEventVirtualAddressChangeGuid,
                   &mRtcVirtualAddrChangeEvent
                   );
   ASSERT_EFI_ERROR (Status);
   return Status;
 }



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Re: [edk2-devel] [edk2-platforms PATCH 2/7] LoongArchQemuPkg/LsRealTimeClockLib: remove superfluous instance init steps
Posted by Chao Li 2 years, 3 months ago 
Hi Laszlo,

This change is look good to me and I will take this change into 
edk2/OvmfPkg/LoongArchVirt/ which I'm porting. Thanks.

Reviewed-by: Chao Li <lichao@loongson.cn>



Thanks,
Chao
在 2023/10/20 20:18, Laszlo Ersek 写道:
> RealTimeClockLib instances are consumed by edk2's
> EmbeddedPkg/RealTimeClockRuntimeDxe driver. In its entry point function
> InitializeRealTimeClock(), the driver:
>
> (1) calls LibRtcInitialize(),
>
> (2) sets the GetTime(), SetTime(), GetWakeupTime() and SetWakeupTime()
>      runtime services to its own similarly-named functions -- where those
>      functions wrap the corresponding RealTimeClockLib APIs,
>
> (3) installs EFI_REAL_TIME_CLOCK_ARCH_PROTOCOL with a NULL protocol
>      interface.
>
> Steps (2) and (3) conform to PI v1.8 sections II-9.7.2.4 through
> II-9.7.2.7.
>
> However, this means that LibRtcInitialize() (of any RealTimeClockLib
> instance) should not itself (a) set the GetTime(), SetTime(),
> GetWakeupTime() and SetWakeupTime() runtime services, nor (b) install
> EFI_REAL_TIME_CLOCK_ARCH_PROTOCOL. The runtime service pointers will be
> overwritten in step (2) anyway, and step (3) will uselessly install a
> second (NULL-interface) EFI_REAL_TIME_CLOCK_ARCH_PROTOCOL instance in the
> protocol database. (The protocol only serves to notify the DXE Foundation
> about said runtime services being available.)
>
> Clean up LoongArchQemuPkg/LsRealTimeClockLib accordingly.
>
> (Note that the lib instance INF file already does not list
> UefiRuntimeServicesTableLib.)
>
> Build-tested only (with "Loongson.dsc").
>
> Cc: Bibo Mao<maobibo@loongson.cn>
> Cc: Chao Li<lichao@loongson.cn>
> Cc: Xianglai li<lixianglai@loongson.cn>
> Ref:https://bugzilla.tianocore.org/show_bug.cgi?id=4565
> Signed-off-by: Laszlo Ersek<lersek@redhat.com>
> ---
>
> Notes:
>      context:-W
>
>   Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.inf |  3 ---
>   Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.c   | 16 ----------------
>   2 files changed, 19 deletions(-)
>
> diff --git a/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.inf b/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.inf
> index 5aa95650f8ba..c5ab1a702167 100644
> --- a/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.inf
> +++ b/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.inf
> @@ -40,8 +40,5 @@ [Pcd]
>   [Guids]
>     gEfiEventVirtualAddressChangeGuid
>   
> -[Protocols]
> -  gEfiRealTimeClockArchProtocolGuid             # PROTOCOL ALWAYS_PRODUCED
> -
>   [Depex]
>     TRUE
> diff --git a/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.c b/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.c
> index eeac011a9400..954589ecb328 100644
> --- a/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.c
> +++ b/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.c
> @@ -1,30 +1,28 @@
>   /** @file
>     Implement EFI RealTimeClock runtime services via RTC Lib.
>   
>     Copyright (c) 2022, Loongson Limited. All rights reserved.
>   
>     SPDX-License-Identifier: BSD-2-Clause-Patent
>   
>   **/
>   
>   #include <Uefi.h>
>   #include <PiDxe.h>
>   
>   #include <Guid/EventGroup.h>
>   #include <Guid/GlobalVariable.h>
>   
>   #include <Library/BaseLib.h>
>   #include <Library/DebugLib.h>
>   #include <Library/DxeServicesTableLib.h>
>   #include <Library/IoLib.h>
>   #include <Library/MemoryAllocationLib.h>
>   #include <Library/PcdLib.h>
>   #include <Library/RealTimeClockLib.h>
>   #include <Library/TimeBaseLib.h>
>   #include <Library/UefiBootServicesTableLib.h>
> -#include <Library/UefiRuntimeServicesTableLib.h>
>   #include <Library/UefiRuntimeLib.h>
> -#include <Protocol/RealTimeClock.h>
>   #include "LsRealTimeClock.h"
>   
>   STATIC BOOLEAN                mInitialized = FALSE;
> @@ -291,46 +289,32 @@ EFIAPI
>   LibRtcInitialize (
>     IN EFI_HANDLE                            ImageHandle,
>     IN EFI_SYSTEM_TABLE                      *SystemTable
>     )
>   {
>     EFI_STATUS    Status;
> -  EFI_HANDLE    Handle;
>   
>     InitRtc ();
>     Status = KvmtoolRtcMapMemory (ImageHandle, (mRtcBase & ~EFI_PAGE_MASK));
>     if (EFI_ERROR (Status)) {
>       DEBUG ((
>         DEBUG_ERROR,
>         "Failed to map memory for loongson 7A RTC. Status = %r\n",
>         Status
>         ));
>       return Status;
>     }
>   
> -  // Setup the setters and getters
> -  gRT->GetTime       = LibGetTime;
> -  gRT->SetTime       = LibSetTime;
> -
> -  // Install the protocol
> -  Handle = NULL;
> -  Status = gBS->InstallMultipleProtocolInterfaces (
> -                  &Handle,
> -                  &gEfiRealTimeClockArchProtocolGuid,  NULL,
> -                  NULL
> -                 );
> -  ASSERT_EFI_ERROR (Status);
> -
>     //
>     // Register for the virtual address change event
>     //
>     Status = gBS->CreateEventEx (
>                     EVT_NOTIFY_SIGNAL,
>                     TPL_NOTIFY,
>                     VirtualNotifyEvent,
>                     NULL,
>                     &gEfiEventVirtualAddressChangeGuid,
>                     &mRtcVirtualAddrChangeEvent
>                     );
>     ASSERT_EFI_ERROR (Status);
>     return Status;
>   }
>
>
>
> 
>
>


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