Hi
Am 12.06.25 um 10:43 schrieb Tomi Valkeinen:
Hi,
On 11/03/2025 17:47, Thomas Zimmermann wrote:
Call drm_mode_size_dumb() to compute dumb-buffer scanline pitch and
buffer size. Align the pitch to a multiple of 8.
Push the current calculation into the only direct caller imx. Imx's
hardware requires the framebuffer width to be aligned to 8. The
driver's current approach is actually incorrect, as it only guarantees
this implicitly and requires bpp to be a multiple of 8 already. A
later commit will fix this problem by aligning the scanline pitch
such that an aligned width still fits into each scanline's memory.
A number of other drivers are build on top of gem-dma helpers and
implement their own dumb-buffer allocation. These drivers invoke
drm_gem_dma_dumb_create_internal(), which is not affected by this
commit.
Signed-off-by: Thomas Zimmermann <tzimmerm...@suse.de>
---
drivers/gpu/drm/drm_gem_dma_helper.c | 7 +++++--
drivers/gpu/drm/imx/ipuv3/imx-drm-core.c | 2 ++
2 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/drm_gem_dma_helper.c
b/drivers/gpu/drm/drm_gem_dma_helper.c
index b7f033d4352a..49be9b033610 100644
--- a/drivers/gpu/drm/drm_gem_dma_helper.c
+++ b/drivers/gpu/drm/drm_gem_dma_helper.c
@@ -20,6 +20,7 @@
#include <drm/drm.h>
#include <drm/drm_device.h>
#include <drm/drm_drv.h>
+#include <drm/drm_dumb_buffers.h>
#include <drm/drm_gem_dma_helper.h>
#include <drm/drm_vma_manager.h>
@@ -304,9 +305,11 @@ int drm_gem_dma_dumb_create(struct drm_file *file_priv,
struct drm_mode_create_dumb *args)
{
struct drm_gem_dma_object *dma_obj;
+ int ret;
- args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
- args->size = args->pitch * args->height;
+ ret = drm_mode_size_dumb(drm, args, SZ_8, 0);
+ if (ret)
+ return ret;
dma_obj = drm_gem_dma_create_with_handle(file_priv, drm, args->size,
&args->handle);
diff --git a/drivers/gpu/drm/imx/ipuv3/imx-drm-core.c
b/drivers/gpu/drm/imx/ipuv3/imx-drm-core.c
index ec5fd9a01f1e..e7025df7b978 100644
--- a/drivers/gpu/drm/imx/ipuv3/imx-drm-core.c
+++ b/drivers/gpu/drm/imx/ipuv3/imx-drm-core.c
@@ -145,6 +145,8 @@ static int imx_drm_dumb_create(struct drm_file *file_priv,
int ret;
args->width = ALIGN(width, 8);
+ args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
+ args->size = args->pitch * args->height;
ret = drm_gem_dma_dumb_create(file_priv, drm, args);
if (ret)
Won't the pitch and size just be overwritten by the
drm_gem_dma_dumb_create() call?
Right, looks like it. Thanks for looking over this. The call to
drm_gem_dma_dumb_create() needs to be changed
drm_gem_dma_dumb_create_internal(). The latter doesn't modify the
arguments besides some sanity checks. BTW patch 10 cleans up imx
entirely. Best regards Thomas
Tomi
--
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstrasse 146, 90461 Nuernberg, Germany
GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
HRB 36809 (AG Nuernberg)
