Re: [PATCH] drm/meson: add size and alignment requirements for dumb buffers

[Sky Zhou]

On 2019/4/8 17:01, Neil Armstrong wrote:
> The Amlogic SoCs Canvas buffers stride must be aligned on 64bytes
> and overall size should be aligned on PAGE width.
> 
> Adds a custom dumb_create op to adds these requirements.
> 
> Fixes: bbbe775ec5b5 ("drm: Add support for Amlogic Meson Graphic Controller")
> Suggested-by: Sky Zhou <sky.zhou@xxxxxxxxxxx>
> Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
> ---
>   drivers/gpu/drm/meson/meson_drv.c | 14 +++++++++++++-
>   1 file changed, 13 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/meson/meson_drv.c b/drivers/gpu/drm/meson/meson_drv.c
> index faf1b1b0357c..72b01e6be0d9 100644
> --- a/drivers/gpu/drm/meson/meson_drv.c
> +++ b/drivers/gpu/drm/meson/meson_drv.c
> @@ -90,6 +90,18 @@ static irqreturn_t meson_irq(int irq, void *arg)
>   	return IRQ_HANDLED;
>   }
>   
> +static int meson_dumb_create(struct drm_file *file, struct drm_device *dev,
> +			     struct drm_mode_create_dumb *args)
> +{
> +	/*
> +	 * We need 64bytes aligned stride, and PAGE aligned size
> +	 */
> +	args->pitch = ALIGN(DIV_ROUND_UP(args->width * args->bpp, 8), SZ_64);
> +	args->size = PAGE_ALIGN(args->pitch * args->height);
> +
> +	return drm_gem_cma_dumb_create_internal(file, dev, args);
> +}
> +
>   DEFINE_DRM_GEM_CMA_FOPS(fops);
>   
>   static struct drm_driver meson_driver = {
> @@ -112,7 +124,7 @@ static struct drm_driver meson_driver = {
>   	.gem_prime_mmap		= drm_gem_cma_prime_mmap,
>   
>   	/* GEM Ops */
> -	.dumb_create		= drm_gem_cma_dumb_create,
> +	.dumb_create		= meson_dumb_create,
>   	.gem_free_object_unlocked = drm_gem_cma_free_object,
>   	.gem_vm_ops		= &drm_gem_cma_vm_ops,
>   
> 

Reviewed-by: Sky Zhou <sky.zhou@xxxxxxxxxxx>