回复: [edk2-devel] [edk2-devel202105 PATCH v2 1/1] ArmPkg/ArmGic: Fix maximum number of interrupts in GICv3

["gaoliming" <gaoliming@byosoft.com.cn>]

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@arm.com
> 抄送: ardb@kernel.org; leif@nuviainc.com; Matteo.Carlini@arm.com;
> Andreas.Sandberg@arm.com; joey.gouly@arm.com; nd@arm.com
> 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@arm.com>
> >
> > 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@arm.com>
> > Signed-off-by: Joey Gouly <joey.gouly@arm.com>
> > Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
> > Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
> > ---
> > 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
> >
> 
> 
> 
> 
>