Re: [PATCH v3] drm/tyr: add Job IRQ handling

[Link Mauve <linkmauve@linkmauve.fr>]

Hi,

On Mon, Aug 03, 2026 at 03:34:37PM +0200, Laura Nao wrote:
> Add a threaded IRQ wrapper for Tyr interrupt sources and use it to
> handle the firmware Job IRQ.
> 
> The Job IRQ reports requests from the CSF firmware, including global
> interface requests and CSG attention bits. Only the GLB bit is currently
> handled, as it will be used to check firmware readiness. CSG bits
> handling will be added at a later stage. Add a Job IRQ handler that
> masks the interrupt in the primary IRQ handler, processes pending raw
> status in the threaded handler, clears the handled bit, and reenables
> the mask before returning.
> Add a wait queue and a bool flag so the handler can signal firmware
> readiness when the GLB bit is set.
[…]
> diff --git a/drivers/gpu/drm/tyr/fw/irq.rs b/drivers/gpu/drm/tyr/fw/irq.rs
> new file mode 100644
> index 000000000000..6eeb1399a7b3
> --- /dev/null
> +++ b/drivers/gpu/drm/tyr/fw/irq.rs
> @@ -0,0 +1,105 @@
[…]
> +/// Requests a threaded IRQ registration for the Job IRQ.
> +///
> +/// # Safety
> +///
> +/// Callers must not `mem::forget()` the resulting registration or otherwise prevent its
> +/// [`Drop`] implementation from running.
> +pub(crate) unsafe fn job_irq_init<'a>(
> +    pdev: &'a platform::Device<Bound>,
> +    iomem: Arc<IoMem<'a>>,
> +    fw_ready: Arc<AtomicBool>,
> +    job_irq_wait: Arc<WaitQueue>,
> +) -> Result<impl PinInit<ThreadedRegistration<'a, TyrIrq<JobIrq<'a>>>, Error> + 'a> {
> +    iomem.write_reg(JOB_IRQ_MASK::zeroed().with_glb(true));
> +    let job_irq = JobIrq {
> +        iomem: iomem.clone(),
> +        fw_ready,
> +        job_irq_wait,
> +    };
> +    // SAFETY: The caller guarantees the resulting registration will not be leaked.
> +    unsafe { TyrIrq::request(pdev, c_str!("job"), job_irq) }

Nowadays we use the shorter c"job" way of creating a &CStr, and I think
the macro will even generate warnings in some configurations (perhaps
CLIPPY=1?).

> +}
> +
> +impl TyrIrqTrait for JobIrq<'_> {
> +    fn read_status(&self) -> u32 {
> +        self.iomem.read(JOB_IRQ_STATUS).into_raw()
> +    }
> +
> +    fn clear_mask(&self) {
> +        self.iomem.write_reg(JOB_IRQ_MASK::zeroed());
> +    }
> +
> +    fn reenable_mask(&self) {
> +        self.iomem.write_reg(JOB_IRQ_MASK::zeroed().with_glb(true));
> +    }
> +
> +    fn read_raw_status(&self) -> u32 {
> +        self.iomem.read(JOB_IRQ_RAWSTAT).into_raw()
> +    }
> +
> +    fn clear_status(&self, status: u32) {
> +        self.iomem.write_reg(JOB_IRQ_CLEAR::from_raw(status));
> +    }
> +
> +    fn mask(&self) -> u32 {
> +        JOB_IRQ_MASK::zeroed().with_glb(true).into_raw()
> +    }
> +
> +    fn handle(&self, status: u32) {
> +        // TODO: handle other Job IRQ events (e.g. CSG attention bits) here once
> +        // support for them is added.
> +        if JOB_IRQ_RAWSTAT::from_raw(status).glb() {
> +            self.fw_ready.store(true, Ordering::Release);
> +            self.job_irq_wait.wake_up_all();
> +        }
> +    }
> +}
> 
> ---
> base-commit: 98ae54f97175c4992b4e5bff53f3c6bc24f0f491
> change-id: 20260728-tyr-irq-v2-0b3c5022be33
> 
> Best regards,
> -- 
> Laura Nao <laura.nao@collabora.com>
> 
> 

Thanks,

-- 
Link Mauve