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Message-ID: <45ef7d6e-d029-4b02-be9e-736dff3724af@collabora.com>
Date: Mon, 25 Mar 2024 09:20:17 +0100
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Subject: Re: [PATCH] drm/panfrost: fix power transition timeout warnings
To: Christian Hewitt <christianshewitt@gmail.com>,
 Boris Brezillon <boris.brezillon@collabora.com>,
 Rob Herring <robh@kernel.org>, Steven Price <steven.price@arm.com>,
 Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
 Maxime Ripard <mripard@kernel.org>, Thomas Zimmermann <tzimmermann@suse.de>,
 David Airlie <airlied@gmail.com>, Daniel Vetter <daniel@ffwll.ch>,
 dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
References: <20240322164525.2617508-1-christianshewitt@gmail.com>
From: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
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In-Reply-To: <20240322164525.2617508-1-christianshewitt@gmail.com>
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Il 22/03/24 17:45, Christian Hewitt ha scritto:
> Increase the timeout value to prevent system logs on Amlogic boards flooding
> with power transition warnings:
> 
> [   13.047638] panfrost ffe40000.gpu: shader power transition timeout
> [   13.048674] panfrost ffe40000.gpu: l2 power transition timeout
> [   13.937324] panfrost ffe40000.gpu: shader power transition timeout
> [   13.938351] panfrost ffe40000.gpu: l2 power transition timeout
> ...
> [39829.506904] panfrost ffe40000.gpu: shader power transition timeout
> [39829.507938] panfrost ffe40000.gpu: l2 power transition timeout
> [39949.508369] panfrost ffe40000.gpu: shader power transition timeout
> [39949.509405] panfrost ffe40000.gpu: l2 power transition timeout
> 
> The 2000 value has been found through trial and error testing with devices
> using G52 and G31 GPUs.
> 
> Fixes: 22aa1a209018 ("drm/panfrost: Really power off GPU cores in panfrost_gpu_power_off()")
> Signed-off-by: Christian Hewitt <christianshewitt@gmail.com>
> ---
>   drivers/gpu/drm/panfrost/panfrost_gpu.c | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/panfrost/panfrost_gpu.c b/drivers/gpu/drm/panfrost/panfrost_gpu.c
> index 9063ce254642..fd8e44992184 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_gpu.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_gpu.c
> @@ -441,19 +441,19 @@ void panfrost_gpu_power_off(struct panfrost_device *pfdev)
>   
>   	gpu_write(pfdev, SHADER_PWROFF_LO, pfdev->features.shader_present);
>   	ret = readl_relaxed_poll_timeout(pfdev->iomem + SHADER_PWRTRANS_LO,
> -					 val, !val, 1, 1000);
> +					 val, !val, 1, 2000);
>   	if (ret)
>   		dev_err(pfdev->dev, "shader power transition timeout");
>   
>   	gpu_write(pfdev, TILER_PWROFF_LO, pfdev->features.tiler_present);
>   	ret = readl_relaxed_poll_timeout(pfdev->iomem + TILER_PWRTRANS_LO,
> -					 val, !val, 1, 1000);
> +					 val, !val, 1, 2000);

Are you sure that you need to raise the timeout for TILER as well?

Cheers,
Angelo

>   	if (ret)
>   		dev_err(pfdev->dev, "tiler power transition timeout");
>   
>   	gpu_write(pfdev, L2_PWROFF_LO, pfdev->features.l2_present);
>   	ret = readl_poll_timeout(pfdev->iomem + L2_PWRTRANS_LO,
> -				 val, !val, 0, 1000);
> +				 val, !val, 0, 2000);
>   	if (ret)
>   		dev_err(pfdev->dev, "l2 power transition timeout");
>   }