The FVP_PLATFORM_TIMER_COUNT is the sum of the memory mapped platform timers and the watchdog timers.
The watchdog timers can be disabled by setting the FVP_WATCHDOG_COUNT (defined by PcdWatchdogCount) to zero. On the VExpress platform, if the FVP_WATCHDOG_COUNT is set to zero, the FVP_PLATFORM_TIMER_COUNT is 1 as VExpress has one memory mapped timer. The code however incorrectly sets the platform timer offset to zero in the GTDT. This causes the OS to read the platform timer information from an invalid offset, and may crash. Updated the GTDT table to set the platform timer offset to zero only when the FVP_PLATFORM_TIMER_COUNT is zero. Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Sami Mujawar <[email protected]> Reviewed-by: Evan Lloyd <[email protected]> --- Notes: v1: - Fix platform timer offset in GTDT for FVP [SAMI] Platform/ARM/VExpressPkg/AcpiTables/Gtdt.aslc | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Platform/ARM/VExpressPkg/AcpiTables/Gtdt.aslc b/Platform/ARM/VExpressPkg/AcpiTables/Gtdt.aslc index ae570574b298094ff468f30b78fbd8c98db506c5..1cb4b498300cf1a08514835677154eace1dd1803 100644 --- a/Platform/ARM/VExpressPkg/AcpiTables/Gtdt.aslc +++ b/Platform/ARM/VExpressPkg/AcpiTables/Gtdt.aslc @@ -108,7 +108,7 @@ FVP_GENERIC_TIMER_DESCRIPTION_TABLES Gtdt = { FVP_GTDT_GTIMER_FLAGS, // UINT32 NonSecurePL2TimerFlags FVP_CNT_READ_BASE_ADDRESS, // UINT64 CntReadBasePhysicalAddress FVP_PLATFORM_TIMER_COUNT, // UINT32 PlatformTimerCount -#if (FVP_WATCHDOG_COUNT != 0) +#if (FVP_PLATFORM_TIMER_COUNT != 0) sizeof (EFI_ACPI_6_1_GENERIC_TIMER_DESCRIPTION_TABLE) // UINT32 PlatfromTimerOffset #else 0 -- 'Guid(CE165669-3EF3-493F-B85D-6190EE5B9759)' _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
