Re: [PATCH] drm/i915: Align initial plane backing objects correctly

[Jani Nikula <jani.nikula@linux.intel.com>]

On Mon, 16 Feb 2015, Jani Nikula <jani.nikula@linux.intel.com> wrote:
> On Wed, 11 Feb 2015, Daniel Vetter <daniel.vetter@ffwll.ch> wrote:
>> Some bios really like to joke and start the planes at an offset ...
>> hooray!
>>
>> Align start and end to fix this.
>>
>> v2: Fixup calculation of size, spotted by Chris Wilson.
>>
>> v3: Fix serious fumble I've just spotted.
>>
>> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=86883
>> Cc: stable@vger.kernel.org
>> Cc: Johannes W <jargon@molb.org>
>> Cc: Chris Wilson <chris@chris-wilson.co.uk>
>> Cc: Jani Nikula <jani.nikula@linux.intel.com>
>> Reported-by: Johannes W <jargon@molb.org>
>> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
>
> Tested-by: Johannes W <jargon@molb.org>

Pushed to drm-intel-fixes, with the WARN_ONs split up separately, thanks
for the patch.

BR,
Jani.


>
>>
>> --
>>
>> Johannes, can you please test this patch instead of the one from
>> Chris?
>>
>> Thanks, Daniel
>> ---
>>  drivers/gpu/drm/i915/i915_gem_stolen.c |  5 +----
>>  drivers/gpu/drm/i915/intel_display.c   | 18 ++++++++++++------
>>  2 files changed, 13 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
>> index 59401f3b902c..4382696087c9 100644
>> --- a/drivers/gpu/drm/i915/i915_gem_stolen.c
>> +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
>> @@ -485,10 +485,7 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
>>  			stolen_offset, gtt_offset, size);
>>  
>>  	/* KISS and expect everything to be page-aligned */
>> -	BUG_ON(stolen_offset & 4095);
>> -	BUG_ON(size & 4095);
>> -
>> -	if (WARN_ON(size == 0))
>> +	if (WARN_ON(size == 0 || stolen_offset & 4095 || size & 4095))
>>  		return NULL;
>>  
>>  	stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
>> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
>> index 2655b63d65e9..fc855b9548ec 100644
>> --- a/drivers/gpu/drm/i915/intel_display.c
>> +++ b/drivers/gpu/drm/i915/intel_display.c
>> @@ -2372,13 +2372,19 @@ intel_alloc_plane_obj(struct intel_crtc *crtc,
>>  	struct drm_i915_gem_object *obj = NULL;
>>  	struct drm_mode_fb_cmd2 mode_cmd = { 0 };
>>  	struct drm_framebuffer *fb = &plane_config->fb->base;
>> -	u32 base = plane_config->base;
>> +	u32 base_aligned = round_down(plane_config->base, PAGE_SIZE);
>> +	u32 size_aligned = round_up(plane_config->base + plane_config->size,
>> +				    PAGE_SIZE);
>> +
>> +	size_aligned -= base_aligned;
>>  
>>  	if (plane_config->size == 0)
>>  		return false;
>>  
>> -	obj = i915_gem_object_create_stolen_for_preallocated(dev, base, base,
>> -							     plane_config->size);
>> +	obj = i915_gem_object_create_stolen_for_preallocated(dev,
>> +							     base_aligned,
>> +							     base_aligned,
>> +							     size_aligned);
>>  	if (!obj)
>>  		return false;
>>  
>> @@ -6654,7 +6660,7 @@ i9xx_get_initial_plane_config(struct intel_crtc *crtc,
>>  	aligned_height = intel_fb_align_height(dev, fb->height,
>>  					       plane_config->tiling);
>>  
>> -	plane_config->size = PAGE_ALIGN(fb->pitches[0] * aligned_height);
>> +	plane_config->size = fb->pitches[0] * aligned_height;
>>  
>>  	DRM_DEBUG_KMS("pipe/plane %c/%d with fb: size=%dx%d@%d, offset=%x, pitch %d, size 0x%x\n",
>>  		      pipe_name(pipe), plane, fb->width, fb->height,
>> @@ -7694,7 +7700,7 @@ skylake_get_initial_plane_config(struct intel_crtc *crtc,
>>  	aligned_height = intel_fb_align_height(dev, fb->height,
>>  					       plane_config->tiling);
>>  
>> -	plane_config->size = ALIGN(fb->pitches[0] * aligned_height, PAGE_SIZE);
>> +	plane_config->size = fb->pitches[0] * aligned_height;
>>  
>>  	DRM_DEBUG_KMS("pipe %c with fb: size=%dx%d@%d, offset=%x, pitch %d, size 0x%x\n",
>>  		      pipe_name(pipe), fb->width, fb->height,
>> @@ -7787,7 +7793,7 @@ ironlake_get_initial_plane_config(struct intel_crtc *crtc,
>>  	aligned_height = intel_fb_align_height(dev, fb->height,
>>  					       plane_config->tiling);
>>  
>> -	plane_config->size = PAGE_ALIGN(fb->pitches[0] * aligned_height);
>> +	plane_config->size = fb->pitches[0] * aligned_height;
>>  
>>  	DRM_DEBUG_KMS("pipe %c with fb: size=%dx%d@%d, offset=%x, pitch %d, size 0x%x\n",
>>  		      pipe_name(pipe), fb->width, fb->height,
>> -- 
>> 2.1.4
>>
>
> -- 
> Jani Nikula, Intel Open Source Technology Center

-- 
Jani Nikula, Intel Open Source Technology Center