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 97A74C982D7 for ; Fri, 16 Jan 2026 15:55:59 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 0826D10E123; Fri, 16 Jan 2026 15:55:59 +0000 (UTC) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by gabe.freedesktop.org (Postfix) with ESMTP id 78BFF10E123 for ; Fri, 16 Jan 2026 15:55:57 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 2CB391515; Fri, 16 Jan 2026 07:55:50 -0800 (PST) Received: from [10.1.27.18] (e122027.cambridge.arm.com [10.1.27.18]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id DF9D63F632; Fri, 16 Jan 2026 07:55:54 -0800 (PST) Message-ID: <9bf6ac3b-5b14-4844-98be-7cd1fa5e00c3@arm.com> Date: Fri, 16 Jan 2026 15:55:53 +0000 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v10 1/4] drm/panthor: Rework panthor_irq::suspended into panthor_irq::state To: Nicolas Frattaroli , Boris Brezillon , Liviu Dudau , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Chia-I Wu , Karunika Choo Cc: kernel@collabora.com, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org References: <20260116-panthor-tracepoints-v10-0-d925986e3d1b@collabora.com> <20260116-panthor-tracepoints-v10-1-d925986e3d1b@collabora.com> From: Steven Price Content-Language: en-GB In-Reply-To: <20260116-panthor-tracepoints-v10-1-d925986e3d1b@collabora.com> Content-Type: text/plain; charset=UTF-8 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 16/01/2026 12:57, 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. > > Co-developed-by: Boris Brezillon > Signed-off-by: Boris Brezillon > Signed-off-by: Nicolas Frattaroli Reviewed-by: Steven Price > --- > drivers/gpu/drm/panthor/panthor_device.h | 35 +++++++++++++++++++++++++------- > 1 file changed, 28 insertions(+), 7 deletions(-) > > diff --git a/drivers/gpu/drm/panthor/panthor_device.h b/drivers/gpu/drm/panthor/panthor_device.h > index f35e52b9546a..8597b388cc40 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; > }; > > /** > @@ -409,12 +420,17 @@ 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 old_state; \ > \ > - if (atomic_read(&pirq->suspended)) \ > - return IRQ_NONE; \ > 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; \ > + \ > gpu_write(ptdev, __reg_prefix ## _INT_MASK, 0); \ > return IRQ_WAKE_THREAD; \ > } \ > @@ -423,6 +439,7 @@ 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 old_state; \ > irqreturn_t ret = IRQ_NONE; \ > \ > while (true) { \ > @@ -435,7 +452,10 @@ static irqreturn_t panthor_ ## __name ## _irq_threaded_handler(int irq, void *da > ret = IRQ_HANDLED; \ > } \ > \ > - if (!atomic_read(&pirq->suspended)) \ > + 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 +465,15 @@ 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); \ > } \ >