[PATCH 3/4] drm/sdma6: properly reference trap interrupts for userqs

[Alex Deucher]

On Mon, Apr 14, 2025 at 5:59 AM Khatri, Sunil <sukhatri at amd.com> wrote:
>
> Same explanation as patch 1 of the series here too. Do we want to depend
> on the disable_kq flag solely to enable/disable sdma trap.
> IIUC, we dont want to do it in case of kernel queues at all and only
> needed when using userqueue and that is taken care by using the flag
> disable_kq.

I think doing it this way makes the most sense because you are using
the presence of user queues to determine whether or not to take the
extra references.  We don't really care what the status of kernel
queues are.

Alex

>
> Regards
> Sunil Khatri
>
> On 4/13/2025 9:36 PM, Alex Deucher wrote:
> > We need to take a reference to the interrupts to make
> > sure they stay enabled even if the kernel queues have
> > disabled them.
> >
> > Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
> > ---
> >   drivers/gpu/drm/amd/amdgpu/sdma_v6_0.c | 31 +++++++++++++++++++++++++-
> >   1 file changed, 30 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v6_0.c b/drivers/gpu/drm/amd/amdgpu/sdma_v6_0.c
> > index 2249a1ef057bf..c3d53974e7f53 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/sdma_v6_0.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/sdma_v6_0.c
> > @@ -1377,11 +1377,39 @@ static int sdma_v6_0_sw_fini(struct amdgpu_ip_block *ip_block)
> >       return 0;
> >   }
> >
> > +static int sdma_v6_0_set_userq_trap_interrupts(struct amdgpu_device *adev,
> > +                                            bool enable)
> > +{
> > +     unsigned int irq_type;
> > +     int i, r;
> > +
> > +     if (adev->userq_funcs[AMDGPU_HW_IP_DMA]) {
> > +             for (i = 0; i < adev->sdma.num_instances; i++) {
> > +                     irq_type = AMDGPU_SDMA_IRQ_INSTANCE0 + i;
> > +                     if (enable)
> > +                             r = amdgpu_irq_get(adev, &adev->sdma.trap_irq,
> > +                                                irq_type);
> > +                     else
> > +                             r = amdgpu_irq_put(adev, &adev->sdma.trap_irq,
> > +                                                irq_type);
> > +                     if (r)
> > +                             return r;
> > +             }
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> >   static int sdma_v6_0_hw_init(struct amdgpu_ip_block *ip_block)
> >   {
> >       struct amdgpu_device *adev = ip_block->adev;
> > +     int r;
> >
> > -     return sdma_v6_0_start(adev);
> > +     r = sdma_v6_0_start(adev);
> > +     if (r)
> > +             return r;
> > +
> > +     return sdma_v6_0_set_userq_trap_interrupts(adev, true);
> >   }
> >
> >   static int sdma_v6_0_hw_fini(struct amdgpu_ip_block *ip_block)
> > @@ -1393,6 +1421,7 @@ static int sdma_v6_0_hw_fini(struct amdgpu_ip_block *ip_block)
> >
> >       sdma_v6_0_ctxempty_int_enable(adev, false);
> >       sdma_v6_0_enable(adev, false);
> > +     sdma_v6_0_set_userq_trap_interrupts(adev, false);
> >
> >       return 0;
> >   }