From: Andreas Sandberg <andreas.sandb...@arm.com> 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 <andreas.sandb...@arm.com> Signed-off-by: Joey Gouly <joey.go...@arm.com> --- The changes can be seen at https://github.com/jgouly/edk2/tree/1396_gic_max_num_intr_v1 ArmPkg/Drivers/ArmGic/ArmGicLib.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/ArmPkg/Drivers/ArmGic/ArmGicLib.c b/ArmPkg/Drivers/ArmGic/ArmGicLib.c index 6b01c88206ad8adef3100dd44c0d57660db77783..c4996970eb299776552fe7b54f34fd5a68afff29 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 +120,12 @@ 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 -- Guid("CE165669-3EF3-493F-B85D-6190EE5B9759") -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#72596): https://edk2.groups.io/g/devel/message/72596 Mute This Topic: https://groups.io/mt/81205553/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
