[PATCH v4] drm/exynos: Add fallback option to get non physically contiguous memory for fb

[Sachin Kamat]

On 6 August 2013 17:22, Vikas Sajjan <vikas.sajjan at linaro.org> wrote:
> While trying to get boot-logo up on exynos5420 SMDK which has eDP panel
> connected with resolution 2560x1600, following error occured even with
> IOMMU enabled:
> [0.880000] [drm:lowlevel_buffer_allocate] *ERROR* failed to allocate buffer.
> [0.890000] [drm] Initialized exynos 1.0.0 20110530 on minor 0
>
> To address the cases where physically contiguous memory MAY NOT be a
> mandatory requirement for fb, the patch adds a feature to get non physically
> contiguous memory for fb if physically contiguous memory allocation fails
> and if IOMMU is supported.
>
> Signed-off-by: Vikas Sajjan <vikas.sajjan at linaro.org>
> Signed-off-by: Arun Kumar <arun.kk at samsung.com>
> Reviewed-by: Rob Clark <robdclark at gmail.com>
> ---
> changes since v3:
>         - addressed nits pointed out by Sylwester Nawrocki <s.nawrocki at samsung.com>
>         and Sachin Kamat <sachin.kamat at linaro.org>.
>
> changes since v2:
>         - addressed comments given by Tomasz Figa <tomasz.figa at gmail.com>.
>
> changes since v1:
>          - Modified to add the fallback patch if CONTIG alloc fails as suggested
>          by Rob Clark robdclark at gmail.com and Tomasz Figa <tomasz.figa at gmail.com>.
>
>          - changed the commit message.
> ---
>  drivers/gpu/drm/exynos/exynos_drm_fbdev.c |   15 +++++++++++++--
>  1 file changed, 13 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
> index 8e60bd6..5292fc7 100644
> --- a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
> +++ b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
> @@ -16,6 +16,7 @@
>  #include <drm/drm_crtc.h>
>  #include <drm/drm_fb_helper.h>
>  #include <drm/drm_crtc_helper.h>
> +#include <drm/exynos_drm.h>
>
>  #include "exynos_drm_drv.h"
>  #include "exynos_drm_fb.h"
> @@ -165,8 +166,18 @@ static int exynos_drm_fbdev_create(struct drm_fb_helper *helper,
>
>         size = mode_cmd.pitches[0] * mode_cmd.height;
>
> -       /* 0 means to allocate physically continuous memory */
> -       exynos_gem_obj = exynos_drm_gem_create(dev, 0, size);
> +       exynos_gem_obj = exynos_drm_gem_create(dev, EXYNOS_BO_CONTIG, size);
> +       /*
> +        * If physically contiguous memory allocation fails and if IOMMU is
> +        * supported then try to get buffer from non physically contiguous
> +        * memory area.
> +        */
> +       if (IS_ERR(exynos_gem_obj) && is_drm_iommu_supported(dev)) {
> +               dev_warn(&pdev->dev, "contiguous FB allocation failed, falling back to non-contiguous\n");
> +               exynos_gem_obj = exynos_drm_gem_create(dev, EXYNOS_BO_NONCONTIG,
> +                                                       size);
> +       }
> +
>         if (IS_ERR(exynos_gem_obj)) {
>                 ret = PTR_ERR(exynos_gem_obj);
>                 goto err_release_framebuffer;
> --
> 1.7.9.5

Looks good to me.

-- 
With warm regards,
Sachin