-----邮件原件-----
发件人: devel@edk2.groups.io <devel@edk2.groups.io> 代表 gaoliming
发送时间: 2021年5月26日 10:22
收件人: devel@edk2.groups.io; lersek@...;
sami.mujawar@...
抄送: ardb@...; leif@...; Matteo.Carlini@...;
Andreas.Sandberg@...; joey.gouly@...; nd@...
主题: 回复: [edk2-devel] [edk2-devel202105 PATCH v2 1/1] ArmPkg/ArmGic:
Fix maximum number of interrupts in GICv3

Laszlo, Ard, Sami:
I am OK to merge this patch for stable tag 202105.

Thanks
Liming

-----邮件原件-----
发件人: devel@edk2.groups.io <devel@edk2.groups.io> 代表 Laszlo

Ersek

发送时间: 2021年5月25日 19:55
收件人: devel@edk2.groups.io; sami.mujawar@...
抄送: ardb@...; leif@...; Matteo.Carlini@...;
Andreas.Sandberg@...; joey.gouly@...; nd@...
主题: Re: [edk2-devel] [edk2-devel202105 PATCH v2 1/1] ArmPkg/ArmGic:
Fix maximum number of interrupts in GICv3

Hi Sami,

On 05/24/21 15:01, Sami Mujawar wrote:

From: Andreas Sandberg <andreas.sandberg@...>

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 <andreas.sandberg@...>
Signed-off-by: Joey Gouly <joey.gouly@...>
Signed-off-by: Sami Mujawar <sami.mujawar@...>
Reviewed-by: Ard Biesheuvel <ardb@...>
---
The changes can be seen at:
https://github.com/samimujawar/edk2/tree/1396_gic_max_num_intr_v2

Notes:
v2:
- Fix comment style.

[Laszlo]

- Updated comment style.

[Sami]

ArmPkg/Drivers/ArmGic/ArmGicLib.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)

I think this patch should be merged really soon, as long as Ard agrees.

Thanks,
Laszlo

diff --git a/ArmPkg/Drivers/ArmGic/ArmGicLib.c

b/ArmPkg/Drivers/ArmGic/ArmGicLib.c

index

6b01c88206ad8adef3100dd44c0d57660db77783..bd4b5edb903f3846f4f0e43

1f93e001f01cd9e7d 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