From d85bf54b7f462eb0297351b5f8dfde09adf617fb Mon Sep 17 00:00:00 2001 From: Laszlo Ersek Date: Fri, 20 Oct 2023 14:17:48 +0200 Subject: ArmPlatformPkg/PL031RealTimeClockLib: remove needless instance init steps 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 Cc: Leif Lindholm Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=4565 Signed-off-by: Laszlo Ersek Message-Id: <20231020121748.44862-1-lersek@redhat.com> Acked-by: Ard Biesheuvel [lersek@redhat.com: shorten patch subject line] --- .../Library/PL031RealTimeClockLib/PL031RealTimeClockLib.c | 13 ------------- 1 file changed, 13 deletions(-) diff --git a/ArmPlatformPkg/Library/PL031RealTimeClockLib/PL031RealTimeClockLib.c b/ArmPlatformPkg/Library/PL031RealTimeClockLib/PL031RealTimeClockLib.c index 9e85269..1896f9d 100644 --- a/ArmPlatformPkg/Library/PL031RealTimeClockLib/PL031RealTimeClockLib.c +++ b/ArmPlatformPkg/Library/PL031RealTimeClockLib/PL031RealTimeClockLib.c @@ -27,8 +27,6 @@ #include #include -#include - #include "PL031RealTimeClock.h" STATIC BOOLEAN mPL031Initialized = FALSE; @@ -310,7 +308,6 @@ LibRtcInitialize ( ) { EFI_STATUS Status; - EFI_HANDLE Handle; // Initialize RTC Base Address mPL031RtcBase = PcdGet32 (PcdPL031RtcBase); @@ -331,16 +328,6 @@ LibRtcInitialize ( 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 // -- cgit v1.1