From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1F607D44C5E for ; Thu, 15 Jan 2026 14:55:35 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 80D0610E777; Thu, 15 Jan 2026 14:55:34 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=collabora.com header.i=@collabora.com header.b="IEZ1eogv"; dkim-atps=neutral Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9418D10E777 for ; Thu, 15 Jan 2026 14:55:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; 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x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Thu, 15 Jan 2026 14:58:59 +0100 Nicolas Frattaroli wrote: > To deal with the threaded interrupt handler and a suspend action > overlapping, the boolean panthor_irq::suspended is not sufficient. > > Rework it into taking several different values depending on the current > state, and check it and set it within the IRQ helper functions. > > Signed-off-by: Nicolas Frattaroli > --- > drivers/gpu/drm/panthor/panthor_device.h | 32 ++++++++++++++++++++++++++------ > 1 file changed, 26 insertions(+), 6 deletions(-) > > diff --git a/drivers/gpu/drm/panthor/panthor_device.h b/drivers/gpu/drm/panthor/panthor_device.h > index f35e52b9546a..2bf9a8434dc5 100644 > --- a/drivers/gpu/drm/panthor/panthor_device.h > +++ b/drivers/gpu/drm/panthor/panthor_device.h > @@ -61,6 +61,17 @@ enum panthor_device_pm_state { > PANTHOR_DEVICE_PM_STATE_SUSPENDING, > }; > > +enum panthor_irq_state { > + /** @PANTHOR_IRQ_STATE_ACTIVE: IRQ is active and ready to process events. */ > + PANTHOR_IRQ_STATE_ACTIVE = 0, > + /** @PANTHOR_IRQ_STATE_PROCESSING: IRQ is currently processing events. */ > + PANTHOR_IRQ_STATE_PROCESSING, > + /** @PANTHOR_IRQ_STATE_SUSPENDED: IRQ is suspended. */ > + PANTHOR_IRQ_STATE_SUSPENDED, > + /** @PANTHOR_IRQ_STATE_SUSPENDING: IRQ is being suspended. */ > + PANTHOR_IRQ_STATE_SUSPENDING, > +}; > + > /** > * struct panthor_irq - IRQ data > * > @@ -76,8 +87,8 @@ struct panthor_irq { > /** @mask: Current mask being applied to xxx_INT_MASK. */ > u32 mask; > > - /** @suspended: Set to true when the IRQ is suspended. */ > - atomic_t suspended; > + /** @state: one of &enum panthor_irq_state reflecting the current state. */ > + atomic_t state; > }; > > /** > @@ -409,8 +420,10 @@ static irqreturn_t panthor_ ## __name ## _irq_raw_handler(int irq, void *data) > { \ > struct panthor_irq *pirq = data; \ > struct panthor_device *ptdev = pirq->ptdev; \ > + enum panthor_irq_state state; \ > \ > - if (atomic_read(&pirq->suspended)) \ > + state = atomic_read(&pirq->state); \ > + if (state == PANTHOR_IRQ_STATE_SUSPENDED || state == PANTHOR_IRQ_STATE_SUSPENDING) \ > return IRQ_NONE; \ > if (!gpu_read(ptdev, __reg_prefix ## _INT_STAT)) \ > return IRQ_NONE; \ I was imagining something like: if (!gpu_read(ptdev, __reg_prefix ## _INT_STAT)) return IRQ_NONE; old_state = atomic_cmpxchg(&pirq->state, PANTHOR_IRQ_STATE_ACTIVE, PANTHOR_IRQ_STATE_PROCESSING); if (old_state != PANTHOR_IRQ_STATE_ACTIVE) return IRQ_NONE; such that the processing phase starts as soon as we know we're going to wake up the irq thread, not when we enter the threaded handler. > @@ -423,8 +436,11 @@ static irqreturn_t panthor_ ## __name ## _irq_threaded_handler(int irq, void *da > { \ > struct panthor_irq *pirq = data; \ > struct panthor_device *ptdev = pirq->ptdev; \ > + enum panthor_irq_state state; \ > irqreturn_t ret = IRQ_NONE; \ > \ > + atomic_cmpxchg(&pirq->state, PANTHOR_IRQ_STATE_ACTIVE, PANTHOR_IRQ_STATE_PROCESSING); \ I think this is better done in the raw_handler (see above). > + \ > while (true) { \ > u32 status = gpu_read(ptdev, __reg_prefix ## _INT_RAWSTAT) & pirq->mask; \ > \ > @@ -435,8 +451,11 @@ static irqreturn_t panthor_ ## __name ## _irq_threaded_handler(int irq, void *da > ret = IRQ_HANDLED; \ > } \ > \ > - if (!atomic_read(&pirq->suspended)) \ > + state = atomic_read(&pirq->state); \ > + if (state != PANTHOR_IRQ_STATE_SUSPENDED && state != PANTHOR_IRQ_STATE_SUSPENDING) { \ > gpu_write(ptdev, __reg_prefix ## _INT_MASK, pirq->mask); \ > + atomic_set(&pirq->state, PANTHOR_IRQ_STATE_ACTIVE); \ > + } \ Similarly, I think I'd go for old_state = atomic_cmpxchg(&pirq->state, PANTHOR_IRQ_STATE_PROCESSING, PANTHOR_IRQ_STATE_ACTIVE); if (old_state == PANTHOR_IRQ_STATE_PROCESSING) gpu_write(ptdev, __reg_prefix ## _INT_MASK, pirq->mask); > \ > return ret; \ > } \ > @@ -445,14 +464,15 @@ static inline void panthor_ ## __name ## _irq_suspend(struct panthor_irq *pirq) > { \ > pirq->mask = 0; \ > gpu_write(pirq->ptdev, __reg_prefix ## _INT_MASK, 0); \ > + atomic_set(&pirq->state, PANTHOR_IRQ_STATE_SUSPENDING); \ > synchronize_irq(pirq->irq); \ > - atomic_set(&pirq->suspended, true); \ > + atomic_set(&pirq->state, PANTHOR_IRQ_STATE_SUSPENDED); \ > } \ > \ > static inline void panthor_ ## __name ## _irq_resume(struct panthor_irq *pirq, u32 mask) \ > { \ > - atomic_set(&pirq->suspended, false); \ > pirq->mask = mask; \ > + atomic_set(&pirq->state, PANTHOR_IRQ_STATE_ACTIVE); \ > gpu_write(pirq->ptdev, __reg_prefix ## _INT_CLEAR, mask); \ > gpu_write(pirq->ptdev, __reg_prefix ## _INT_MASK, mask); \ > } \ >