From e1999b264f1f9d7230edf2448f757c73da567832 Mon Sep 17 00:00:00 2001 From: Andreas Sandberg Date: Tue, 9 Mar 2021 16:45:10 +0000 Subject: ArmPkg/ArmGic: Fix maximum number of interrupts in GICv3 Bugzilla: 3415 (https://bugzilla.tianocore.org/show_bug.cgi?id=3415) The GICv3 architecture supports up to 1020 ordinary interrupt lines. The actual number of interrupts supported is described by the ITLinesNumber field in the GICD_TYPER register. The total number of implemented registers is normally calculated as 32*(ITLinesNumber+1). However, maximum value (0x1f) is a special case since that would indicate that 1024 interrupts are implemented. Add handling for this special case in ArmGicGetMaxNumInterrupts. Signed-off-by: Andreas Sandberg Signed-off-by: Joey Gouly Signed-off-by: Sami Mujawar Reviewed-by: Ard Biesheuvel Reviewed-by: Philippe Mathieu-Daude --- ArmPkg/Drivers/ArmGic/ArmGicLib.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'ArmPkg/Drivers/ArmGic') diff --git a/ArmPkg/Drivers/ArmGic/ArmGicLib.c b/ArmPkg/Drivers/ArmGic/ArmGicLib.c index 6b01c88206..bd4b5edb90 100644 --- a/ArmPkg/Drivers/ArmGic/ArmGicLib.c +++ b/ArmPkg/Drivers/ArmGic/ArmGicLib.c @@ -1,6 +1,6 @@ /** @file * -* Copyright (c) 2011-2018, ARM Limited. All rights reserved. +* Copyright (c) 2011-2021, Arm Limited. All rights reserved. * * SPDX-License-Identifier: BSD-2-Clause-Patent * @@ -120,7 +120,14 @@ ArmGicGetMaxNumInterrupts ( IN INTN GicDistributorBase ) { - return 32 * ((MmioRead32 (GicDistributorBase + ARM_GIC_ICDICTR) & 0x1F) + 1); + UINTN ItLines; + + ItLines = MmioRead32 (GicDistributorBase + ARM_GIC_ICDICTR) & 0x1F; + + // + // Interrupt ID 1020-1023 are reserved. + // + return (ItLines == 0x1f) ? 1020 : 32 * (ItLines + 1); } VOID -- cgit v1.2.3