On 07/19/2012 02:46 PM, Laurent Pinchart wrote:
> Hi Lars,
>
> Thank you for the patch.
>
> On Monday 02 July 2012 16:37:47 Lars-Peter Clausen wrote:
>> This patchset introduces a set of helper function for implementing the KMS
>> framebuffer layer for drivers which use the drm gem CMA helper function.
>>
>> Signed-off-by: Lars-Peter Clausen <lars at metafoo.de>
>>
>> ---
>> Note: This patch depends on Sascha's "DRM: add drm gem CMA helper" patch
>>
>> Changes since v2:
>> * Adapt to changes in the GEM CMA helper
>> * Add basic buffer size checking in drm_fb_cma_create
>> Changes since v1:
>> * Some spelling fixes
>> * Add missing kfree in drm_fb_cma_alloc error path
>> * Add multi-plane support
>> ---
>> drivers/gpu/drm/Kconfig | 10 +
>> drivers/gpu/drm/Makefile | 1 +
>> drivers/gpu/drm/drm_fb_cma_helper.c | 393 ++++++++++++++++++++++++++++++++
>> include/drm/drm_fb_cma_helper.h | 27 +++
>> 4 files changed, 431 insertions(+)
>> create mode 100644 drivers/gpu/drm/drm_fb_cma_helper.c
>> create mode 100644 include/drm/drm_fb_cma_helper.h
>
> [snip]
>
>> diff --git a/drivers/gpu/drm/drm_fb_cma_helper.c
>> b/drivers/gpu/drm/drm_fb_cma_helper.c new file mode 100644
>> index 0000000..9042233
>> --- /dev/null
>> +++ b/drivers/gpu/drm/drm_fb_cma_helper.c
>
> [snip]
>
>> +/**
>> + * drm_fb_cma_create() - (struct drm_mode_config_funcs *)->fb_create
>> callback function
>> + *
>> + * If your hardware has special alignment or pitch requirements these
>> should be
>> + * checked before calling this function.
>> + */
>> +struct drm_framebuffer *drm_fb_cma_create(struct drm_device *dev,
>> + struct drm_file *file_priv, struct drm_mode_fb_cmd2 *mode_cmd)
>> +{
>> + struct drm_fb_cma *fb_cma;
>> + struct drm_gem_cma_object *objs[4];
>> + struct drm_gem_object *obj;
>> + int ret;
>> + int i;
>> +
>> + for (i = 0; i < drm_format_num_planes(mode_cmd->pixel_format); i++) {
>> + obj = drm_gem_object_lookup(dev, file_priv,
>> mode_cmd->handles[i]);
>> + if (!obj) {
>> + dev_err(dev->dev, "Failed to lookup GEM object\n");
>> + ret = -ENXIO;
>> + goto err_gem_object_unreference;
>> + }
>> +
>> + if (obj->size < mode_cmd->height * mode_cmd->pitches[i]) {
>
> Shouldn't this be
>
> if (obj->size < mode_cmd->height * mode_cmd->pitches[i]
> + mode_cmd->offsets[i])
>
> ?
That's actually a good question. I'd expect the offset to be included in the
pitch.
If you access pixels like mem[offset + x * bpp + y * pitch] then pitch has
to be greater equal to offset + max_x * bpp, otherwise you'd have
overlapping lines.
Thanks,
- Lars
