Re: [PATCH] drm/msm: Fix wrong size calculation

[Dmitry Baryshkov]

On 12/01/2022 15:33, Xianting Tian wrote:
> For example, memory-region in .dts as below,
> 	reg = <0x0 0x50000000 0x0 0x20000000>
>
> We can get below values,
> struct resource r;
> r.start = 0x50000000;
> r.end	= 0x6fffffff;
>
> So the size should be:
> size = r.end - r.start + 1 = 0x20000000
>
> Signed-off-by: Xianting Tian <xianting.tian@xxxxxxxxxxxxxxxxx>

Fixes: 072f1f9168ed ("drm/msm: add support for "stolen" mem")
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>

> ---
>   drivers/gpu/drm/msm/msm_drv.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
> index 892c04365..f04a2337d 100644
> --- a/drivers/gpu/drm/msm/msm_drv.c
> +++ b/drivers/gpu/drm/msm/msm_drv.c
> @@ -466,7 +466,7 @@ static int msm_init_vram(struct drm_device *dev)
>   		of_node_put(node);
>   		if (ret)
>   			return ret;
> -		size = r.end - r.start;
> +		size = r.end - r.start + 1;
>   		DRM_INFO("using VRAM carveout: %lx@%pa\n", size, &r.start);
>   
>   		/* if we have no IOMMU, then we need to use carveout allocator.


--
With best wishes
Dmitry