On Tue, May 12, 2026 at 4:54 AM Boris Brezillon
<[email protected]> wrote:
>
> Now that everything is set to allow processing FW events in IRQ context,
> go for it. This should reduce the dma_fence signaling latency.
>
> Signed-off-by: Boris Brezillon <[email protected]>
> ---
> drivers/gpu/drm/panthor/panthor_fw.c | 27 +++++++++++++++++++++++----
> 1 file changed, 23 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/panthor/panthor_fw.c
> b/drivers/gpu/drm/panthor/panthor_fw.c
> index f5e0ceca4130..8cfebf180de7 100644
> --- a/drivers/gpu/drm/panthor/panthor_fw.c
> +++ b/drivers/gpu/drm/panthor/panthor_fw.c
> @@ -1087,9 +1087,29 @@ static void panthor_job_irq_handler(struct panthor_irq
> *pirq, u32 status)
> }
> }
>
> -static irqreturn_t panthor_job_irq_threaded_handler(int irq, void *data)
> +static irqreturn_t panthor_job_irq_raw_handler(int irq, void *data)
> {
> - return panthor_irq_default_threaded_handler(data,
> panthor_job_irq_handler);
> + struct panthor_irq *pirq = data;
> +
> + if (!gpu_read(pirq->iomem, INT_STAT))
> + return IRQ_NONE;
> +
> + scoped_guard(spinlock_irqsave, &pirq->mask_lock) {
> + if (pirq->state != PANTHOR_IRQ_STATE_ACTIVE)
> + return IRQ_NONE;
> +
> + pirq->state = PANTHOR_IRQ_STATE_PROCESSING;
> + }
> +
> + /* We can use INT_STAT here, because we didn't mask the IRQs. */
> + panthor_job_irq_handler(pirq, gpu_read(pirq->iomem, INT_STAT));
We should loop here until INT_STAT is cleared.
> +
> + scoped_guard(spinlock_irqsave, &pirq->mask_lock) {
> + if (pirq->state == PANTHOR_IRQ_STATE_PROCESSING)
> + pirq->state = PANTHOR_IRQ_STATE_ACTIVE;
> + }
> +
> + return IRQ_HANDLED;
> }
>
> static int panthor_fw_start(struct panthor_device *ptdev)
> @@ -1489,8 +1509,7 @@ int panthor_fw_init(struct panthor_device *ptdev)
>
> ret = panthor_irq_request(ptdev, &fw->irq, irq, 0,
> ptdev->iomem + JOB_INT_BASE, "job",
> - panthor_irq_default_raw_handler,
> - panthor_job_irq_threaded_handler);
> + panthor_job_irq_raw_handler, NULL);
> if (ret) {
> drm_err(&ptdev->base, "failed to request job irq");
> return ret;
>
> --
> 2.54.0
>
