Re: [PATCH v2 14/22] drm/exynos: fimd: fix dma burst size setting for small plane size

[Inki Dae <inki.dae@samsung.com>]

2015년 12월 10일 21:59에 Marek Szyprowski 이(가) 쓴 글:
> Hello,
> 
> On 2015-12-10 12:35, Inki Dae wrote:
>> Hi Marek,
>>
>> 2015년 11월 30일 22:53에 Marek Szyprowski 이(가) 쓴 글:
>>> This patch fixes trashed display of buffers cropped to very small width.
>>> Even if DMA is unstable and causes tearing when changing the burst size,
>>> it is still better than displaying a garbage.
>> It seems that this patch is different from above description. I think below patch is just cleanup,
>> which passes each member necessary instead of passing a drm_framebuffer object.
> 
> Please note the last chunk of this patch. After applying it width is
> taken from state->src.w instead of fb->width. If you want, I can split
> this patch into 2 parts - one cleanup without functional change, and
> second, replacement of fb->width with state->src.w.

Will just merge it.

Thanks,
Inki Dae

> 
> 
>>
>>> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
>>> ---
>>>   drivers/gpu/drm/exynos/exynos_drm_fimd.c | 24 +++++++++++-------------
>>>   1 file changed, 11 insertions(+), 13 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/exynos/exynos_drm_fimd.c b/drivers/gpu/drm/exynos/exynos_drm_fimd.c
>>> index 70cd2681e343..2e2247126581 100644
>>> --- a/drivers/gpu/drm/exynos/exynos_drm_fimd.c
>>> +++ b/drivers/gpu/drm/exynos/exynos_drm_fimd.c
>>> @@ -487,7 +487,7 @@ static void fimd_commit(struct exynos_drm_crtc *crtc)
>>>       static void fimd_win_set_pixfmt(struct fimd_context *ctx, unsigned int win,
>>> -                struct drm_framebuffer *fb)
>>> +                uint32_t pixel_format, int width)
>>>   {
>>>       unsigned long val;
>>>   @@ -498,11 +498,11 @@ static void fimd_win_set_pixfmt(struct fimd_context *ctx, unsigned int win,
>>>        * So the request format is ARGB8888 then change it to XRGB8888.
>>>        */
>>>       if (ctx->driver_data->has_limited_fmt && !win) {
>>> -        if (fb->pixel_format == DRM_FORMAT_ARGB8888)
>>> -            fb->pixel_format = DRM_FORMAT_XRGB8888;
>>> +        if (pixel_format == DRM_FORMAT_ARGB8888)
>>> +            pixel_format = DRM_FORMAT_XRGB8888;
>>>       }
>>>   -    switch (fb->pixel_format) {
>>> +    switch (pixel_format) {
>>>       case DRM_FORMAT_C8:
>>>           val |= WINCON0_BPPMODE_8BPP_PALETTE;
>>>           val |= WINCONx_BURSTLEN_8WORD;
>>> @@ -538,17 +538,15 @@ static void fimd_win_set_pixfmt(struct fimd_context *ctx, unsigned int win,
>>>           break;
>>>       }
>>>   -    DRM_DEBUG_KMS("bpp = %d\n", fb->bits_per_pixel);
>>> -
>>>       /*
>>> -     * In case of exynos, setting dma-burst to 16Word causes permanent
>>> -     * tearing for very small buffers, e.g. cursor buffer. Burst Mode
>>> -     * switching which is based on plane size is not recommended as
>>> -     * plane size varies alot towards the end of the screen and rapid
>>> -     * movement causes unstable DMA which results into iommu crash/tear.
>>> +     * Setting dma-burst to 16Word causes permanent tearing for very small
>>> +     * buffers, e.g. cursor buffer. Burst Mode switching which based on
>>> +     * plane size is not recommended as plane size varies alot towards the
>>> +     * end of the screen and rapid movement causes unstable DMA, but it is
>>> +     * still better to change dma-burst than displaying garbage.
>>>        */
>>>   -    if (fb->width < MIN_FB_WIDTH_FOR_16WORD_BURST) {
>>> +    if (width < MIN_FB_WIDTH_FOR_16WORD_BURST) {
>>>           val &= ~WINCONx_BURSTLEN_MASK;
>>>           val |= WINCONx_BURSTLEN_4WORD;
>>>       }
>>> @@ -723,7 +721,7 @@ static void fimd_update_plane(struct exynos_drm_crtc *crtc,
>>>           DRM_DEBUG_KMS("osd size = 0x%x\n", (unsigned int)val);
>>>       }
>>>   -    fimd_win_set_pixfmt(ctx, win, fb);
>>> +    fimd_win_set_pixfmt(ctx, win, fb->pixel_format, state->src.w);
>>>         /* hardware window 0 doesn't support color key. */
>>>       if (win != 0)
>>>
> 
> Best regards