On 10/20/23 14:27, Ard Biesheuvel wrote: > On Fri, 20 Oct 2023 at 14:17, Laszlo Ersek <ler...@redhat.com> wrote: >> >> 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 ArmPlatformPkg/PL031RealTimeClockLib accordingly (it only has >> code that's redundant for step (3); it does not try to set "gRT" fields). >> >> (Note that the lib instance INF file already does not list >> gEfiRealTimeClockArchProtocolGuid.) >> >> Tested with ArmVirtQemu. >> >> Cc: Ard Biesheuvel <ardb+tianoc...@kernel.org> >> Cc: Leif Lindholm <quic_llind...@quicinc.com> >> Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=4565 >> Signed-off-by: Laszlo Ersek <ler...@redhat.com> >> --- >> >> Notes: >> context:-W >> >> ArmPlatformPkg/Library/PL031RealTimeClockLib/PL031RealTimeClockLib.c | 13 >> ------------- >> 1 file changed, 13 deletions(-) >> > > Acked-by: Ard Biesheuvel <a...@kernel.org> > > Thanks a lot for cleaning up this mess.
Merged via <https://github.com/tianocore/edk2/pull/4950> as commit d85bf54b7f46. Thanks! Laszlo > > >> diff --git >> a/ArmPlatformPkg/Library/PL031RealTimeClockLib/PL031RealTimeClockLib.c >> b/ArmPlatformPkg/Library/PL031RealTimeClockLib/PL031RealTimeClockLib.c >> index 9e852696d2fd..1896f9d16d3b 100644 >> --- a/ArmPlatformPkg/Library/PL031RealTimeClockLib/PL031RealTimeClockLib.c >> +++ b/ArmPlatformPkg/Library/PL031RealTimeClockLib/PL031RealTimeClockLib.c >> @@ -1,34 +1,32 @@ >> /** @file >> Implement EFI RealTimeClock runtime services via RTC Lib. >> >> Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR> >> Copyright (c) 2011 - 2020, Arm Limited. All rights reserved.<BR> >> Copyright (c) 2019, Linaro Ltd. All rights reserved.<BR> >> >> SPDX-License-Identifier: BSD-2-Clause-Patent >> >> **/ >> >> #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/UefiLib.h> >> #include <Library/UefiRuntimeServicesTableLib.h> >> #include <Library/UefiRuntimeLib.h> >> >> -#include <Protocol/RealTimeClock.h> >> - >> #include "PL031RealTimeClock.h" >> >> STATIC BOOLEAN mPL031Initialized = FALSE; >> @@ -307,52 +305,41 @@ EFIAPI >> LibRtcInitialize ( >> IN EFI_HANDLE ImageHandle, >> IN EFI_SYSTEM_TABLE *SystemTable >> ) >> { >> EFI_STATUS Status; >> - EFI_HANDLE Handle; >> >> // Initialize RTC Base Address >> mPL031RtcBase = PcdGet32 (PcdPL031RtcBase); >> >> // Declare the controller as EFI_MEMORY_RUNTIME >> Status = gDS->AddMemorySpace ( >> EfiGcdMemoryTypeMemoryMappedIo, >> mPL031RtcBase, >> SIZE_4KB, >> EFI_MEMORY_UC | EFI_MEMORY_RUNTIME >> ); >> if (EFI_ERROR (Status)) { >> return Status; >> } >> >> Status = gDS->SetMemorySpaceAttributes (mPL031RtcBase, SIZE_4KB, >> EFI_MEMORY_UC | EFI_MEMORY_RUNTIME); >> if (EFI_ERROR (Status)) { >> return Status; >> } >> >> - // 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; >> } > > > > > -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#110008): https://edk2.groups.io/g/devel/message/110008 Mute This Topic: https://groups.io/mt/102079629/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/leave/9847357/21656/1706620634/xyzzy [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
