lkml.org 
[lkml]   [2017]   [Nov]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH 2/2] drm/vc4: Ensure interrupts are disabled
Date
Stefan Schake <stschake@gmail.com> writes:

> On Tue, Nov 14, 2017 at 1:18 AM, Eric Anholt <eric@anholt.net> wrote:
>> Stefan Schake <stschake@gmail.com> writes:
>>
>>> The overflow mem work callback vc4_overflow_mem_work reenables its
>>> associated interrupt upon completion. To ensure all interrupts are disabled
>>> when we return from vc4_irq_uninstall, we need to disable it again if
>>> cancel_work_sync indicated pending work.
>>
>> Is there a reason we need the interrupts disabled at the V3D level while
>> we have the IRQ disabled at the irqchip level? Once we re-enable at the
>> irqchip, we immediately V3D_WRITE(V3D_INTENA, V3D_DRIVER_IRQS) anyway.
>
> irqchip will mask it in the ARM interrupt controller, so we will certainly never
> see an interrupt. I'm not sure on the exact guarantees V3D_INTENA and
> V3D_INTCTL make - does the state in INTENA affect if V3D will signal an
> interrupt in INTCTL? We're not currently clearing the latter in postinstall.

INTENA/INTDIS writes update the state of the single register that
controls which bits of INTCTL get ORed together to raise the interrupt
outside the V3D block.
[unhandled content-type:application/pgp-signature]
\
 
 \ /
  Last update: 2017-11-14 20:45    [W:0.042 / U:3.440 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site