drm/msm: Fix wrong size calculation

commit 0a727b459ee39bd4c5ced19d6024258ac87b6b2e upstream.

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@linux.alibaba.com>
Fixes: 072f1f9168ed ("drm/msm: add support for "stolen" mem")
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20220112123334.749776-1-xianting.tian@linux.alibaba.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
index 08ff9d7645d74c3868d3f5edb8332e4608d0bc27..11bad11101b9e107d0056eb22b493e4d749100ff 100644 (file)
--- a/drivers/gpu/drm/msm/msm_drv.c
+++ b/drivers/gpu/drm/msm/msm_drv.c
@@ -388,7 +388,7 @@ 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.