The generic watchdog offset register is 48 bits wide, and can be set by performing two 32-bit writes.
Add support for writing the high 16 bits of the offset register and update the signature of the WatchdogWriteOffsetRegister function to take a UINT64 value. Signed-off-by: Rebecca Cran <rebe...@os.amperecomputing.com> --- ArmPkg/Drivers/GenericWatchdogDxe/GenericWatchdog.h | 11 +++++++++- ArmPkg/Drivers/GenericWatchdogDxe/GenericWatchdogDxe.c | 23 +++++++++++++++----- 2 files changed, 27 insertions(+), 7 deletions(-) diff --git a/ArmPkg/Drivers/GenericWatchdogDxe/GenericWatchdog.h b/ArmPkg/Drivers/GenericWatchdogDxe/GenericWatchdog.h index 9bc3bf47047c..fb117832683f 100644 --- a/ArmPkg/Drivers/GenericWatchdogDxe/GenericWatchdog.h +++ b/ArmPkg/Drivers/GenericWatchdogDxe/GenericWatchdog.h @@ -1,9 +1,13 @@ /** @file * +* Copyright (c) 2023, Ampere Computing LLC. All rights reserved.<BR> * Copyright (c) 2013-2017, ARM Limited. All rights reserved. * * SPDX-License-Identifier: BSD-2-Clause-Patent * +* @par Reference(s): +* - Generic Watchdog specification in Arm Base System Architecture 1.0C: +* https://developer.arm.com/documentation/den0094/c/ **/ #ifndef GENERIC_WATCHDOG_H_ @@ -14,12 +18,17 @@ // Control Frame: #define GENERIC_WDOG_CONTROL_STATUS_REG ((UINTN)FixedPcdGet64 (PcdGenericWatchdogControlBase) + 0x000) -#define GENERIC_WDOG_OFFSET_REG ((UINTN)FixedPcdGet64 (PcdGenericWatchdogControlBase) + 0x008) +#define GENERIC_WDOG_OFFSET_REG_LOW ((UINTN)FixedPcdGet64 (PcdGenericWatchdogControlBase) + 0x008) +#define GENERIC_WDOG_OFFSET_REG_HIGH ((UINTN)FixedPcdGet64 (PcdGenericWatchdogControlBase) + 0x00C) #define GENERIC_WDOG_COMPARE_VALUE_REG_LOW ((UINTN)FixedPcdGet64 (PcdGenericWatchdogControlBase) + 0x010) #define GENERIC_WDOG_COMPARE_VALUE_REG_HIGH ((UINTN)FixedPcdGet64 (PcdGenericWatchdogControlBase) + 0x014) +#define GENERIC_WDOG_IID_REG ((UINTN)FixedPcdGet64 (PcdGenericWatchdogControlBase) + 0xFCC) // Values of bit 0 of the Control/Status Register #define GENERIC_WDOG_ENABLED 1 #define GENERIC_WDOG_DISABLED 0 +#define GENERIC_WDOG_IID_REV_SHIFT 16 +#define GENERIC_WDOG_IID_REV_MASK 0xF + #endif // GENERIC_WATCHDOG_H_ diff --git a/ArmPkg/Drivers/GenericWatchdogDxe/GenericWatchdogDxe.c b/ArmPkg/Drivers/GenericWatchdogDxe/GenericWatchdogDxe.c index 66c6c37c08b0..20549aa91d94 100644 --- a/ArmPkg/Drivers/GenericWatchdogDxe/GenericWatchdogDxe.c +++ b/ArmPkg/Drivers/GenericWatchdogDxe/GenericWatchdogDxe.c @@ -1,5 +1,6 @@ /** @file * +* Copyright (c) 2023, Ampere Computing LLC. All rights reserved.<BR> * Copyright (c) 2013-2018, ARM Limited. All rights reserved. * * SPDX-License-Identifier: BSD-2-Clause-Patent @@ -35,16 +36,23 @@ STATIC UINTN mTimerFrequencyHz = 0; It is therefore stored here. 0 means the timer is not running. */ STATIC UINT64 mNumTimerTicks = 0; +STATIC UINT8 WatchdogRevision; + +#define MAX_UINT48 0xFFFFFFFFFFFFULL + STATIC EFI_HARDWARE_INTERRUPT2_PROTOCOL *mInterruptProtocol; STATIC EFI_WATCHDOG_TIMER_NOTIFY mWatchdogNotify; STATIC VOID WatchdogWriteOffsetRegister ( - UINT32 Value + UINT64 Value ) { - MmioWrite32 (GENERIC_WDOG_OFFSET_REG, Value); + MmioWrite32 (GENERIC_WDOG_OFFSET_REG_LOW, Value & MAX_UINT32); + if (WatchdogRevision == 1) { + MmioWrite32 (GENERIC_WDOG_OFFSET_REG_HIGH, (Value >> 32) & MAX_UINT16); + } } STATIC @@ -211,17 +219,17 @@ WatchdogSetTimerPeriod ( /* If the number of required ticks is greater than the max the watchdog's offset register (WOR) can hold, we need to manually compute and set the compare register (WCV) */ - if (mNumTimerTicks > MAX_UINT32) { + if (mNumTimerTicks > MAX_UINT48) { /* We need to enable the watchdog *before* writing to the compare register, because enabling the watchdog causes an "explicit refresh", which clobbers the compare register (WCV). In order to make sure this doesn't trigger an interrupt, set the offset to max. */ - WatchdogWriteOffsetRegister (MAX_UINT32); + WatchdogWriteOffsetRegister (MAX_UINT48); WatchdogEnable (); SystemCount = ArmGenericTimerGetSystemCount (); WatchdogWriteCompareRegister (SystemCount + mNumTimerTicks); } else { - WatchdogWriteOffsetRegister ((UINT32)mNumTimerTicks); + WatchdogWriteOffsetRegister (mNumTimerTicks); WatchdogEnable (); } @@ -310,6 +318,7 @@ GenericWatchdogEntry ( { EFI_STATUS Status; EFI_HANDLE Handle; + UINT32 WatchdogIId; Status = gBS->LocateProtocol ( &gHardwareInterrupt2ProtocolGuid, @@ -367,7 +376,9 @@ GenericWatchdogEntry ( ); ASSERT_EFI_ERROR (Status); - mNumTimerTicks = 0; + mNumTimerTicks = 0; + WatchdogIId = MmioRead32 (GENERIC_WDOG_IID_REG); + WatchdogRevision = (WatchdogIId >> GENERIC_WDOG_IID_REV_SHIFT) & GENERIC_WDOG_IID_REV_MASK; WatchdogDisable (); return EFI_SUCCESS; -- 2.34.1 -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#114088): https://edk2.groups.io/g/devel/message/114088 Mute This Topic: https://groups.io/mt/103832319/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
