This commit fixes a bug in the GIC v2 and v3 drivers where the GICC_EOIR
(End Of Interrupt Register) is written twice for a single interrupt.
GicV(2|3)IrqInterruptHandler() calls the Interrupt Handler and then
GicV(2|3)EndOfInterrupt() on exit:
InterruptHandler = gRegisteredInterruptHandlers[GicInterrupt];
if (InterruptHandler != NULL) {
// Call the registered interrupt handler.
InterruptHandler (GicInterrupt, SystemContext);
} else {
DEBUG ((EFI_D_ERROR, "Spurious GIC interrupt: 0x%x\n", GicInterrupt));
}
GicV2EndOfInterrupt (&gHardwareInterruptV2Protocol, GicInterrupt);
although gInterrupt->EndOfInterrupt() can be expected to have already
been called by InterruptHandler() [which is the case for the primary
in-tree handler in TimerDxe]
The fix moves the EndOfInterrupt() call inside the else case for
unregistered/spurious interrupts. This removes a potential race
condition that might have lost interrupts.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Alexei Fedorov <alexei.fedorov@arm.com>
Signed-off-by: Evan Lloyd <evan.lloyd@arm.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
7989300df7