[PATCH 8/8] drm/exynos: fimd: add complete_scanout function

[Sean Paul]

On Wed, Dec 26, 2012 at 6:27 AM, Prathyush K <prathyush.k at samsung.com> wrote:
> The wait_for_vblank interface is modified to the complete_scanout
> function in fimd. This patch adds the fimd_complete_scanout function
>
> Inside fimd_complete_scanout, we read the shadow register for each
> window and compare it with the dma address of the framebuffer. If
> the dma_address is in the shadow register, then the function waits
> for the next vblank and returns.
>
> Signed-off-by: Prathyush K <prathyush.k at samsung.com>
> ---
>  drivers/gpu/drm/exynos/exynos_drm_fimd.c | 32 +++++++++++++++++++++++++++++++-
>  include/video/samsung_fimd.h             |  1 +
>  2 files changed, 32 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/exynos/exynos_drm_fimd.c b/drivers/gpu/drm/exynos/exynos_drm_fimd.c
> index 3aeedf5..190ffde9 100644
> --- a/drivers/gpu/drm/exynos/exynos_drm_fimd.c
> +++ b/drivers/gpu/drm/exynos/exynos_drm_fimd.c
> @@ -46,6 +46,7 @@
>  #define VIDOSD_D(win)          (VIDOSD_BASE + 0x0C + (win) * 16)
>
>  #define VIDWx_BUF_START(win, buf)      (VIDW_BUF_START(buf) + (win) * 8)
> +#define VIDWx_BUF_START_S(win, buf)    (VIDW_BUF_START_S(buf) + (win) * 8)
>  #define VIDWx_BUF_END(win, buf)                (VIDW_BUF_END(buf) + (win) * 8)
>  #define VIDWx_BUF_SIZE(win, buf)       (VIDW_BUF_SIZE(buf) + (win) * 4)
>
> @@ -363,13 +364,42 @@ static void fimd_wait_for_vblank(struct device *dev)
>                 fimd_disable_vblank(dev);
>  }
>
> +static void fimd_complete_scanout(struct device *dev, dma_addr_t dma_addr,
> +                                       unsigned long size)
> +{
> +       struct fimd_context *ctx = get_fimd_context(dev);
> +       int win;
> +       bool in_use = false;
> +
> +       if (ctx->suspended)
> +               return;
> +

Is this really possible? If it is, I think there's potential for
trouble. It seems possible that an fb is current, but we're suspended.
If we exit early here, the fb will be freed and we'll be sad when we
come out of suspend.

> +       for (win = 0; win < WINDOWS_NR; win++) {
> +               dma_addr_t dma_addr_in_use;
> +
> +               if (!ctx->win_data[win].enabled)
> +                       continue;
> +
> +               dma_addr_in_use = readl(ctx->regs + VIDWx_BUF_START_S(win, 0));
> +               if (dma_addr_in_use >= dma_addr &&
> +                       dma_addr_in_use < (dma_addr + size)) {
> +                               in_use = true;
> +                               break;
> +               }

I think this has the opposite problem as your mixer patch. You're
checking if the framebuffer is in the shadow register, but I don't
think this code will wait if the fb is currently being scanned out. I
hope I'm just missing something :)

Sean



> +       }
> +
> +       if (in_use)
> +               fimd_wait_for_vblank(dev);
> +       return;
> +}
> +
>  static struct exynos_drm_manager_ops fimd_manager_ops = {
>         .dpms = fimd_dpms,
>         .apply = fimd_apply,
>         .commit = fimd_commit,
>         .enable_vblank = fimd_enable_vblank,
>         .disable_vblank = fimd_disable_vblank,
> -       .wait_for_vblank = fimd_wait_for_vblank,
> +       .complete_scanout = fimd_complete_scanout,
>  };
>
>  static void fimd_win_mode_set(struct device *dev,
> diff --git a/include/video/samsung_fimd.h b/include/video/samsung_fimd.h
> index 7ae6c07..382eaec 100644
> --- a/include/video/samsung_fimd.h
> +++ b/include/video/samsung_fimd.h
> @@ -274,6 +274,7 @@
>
>  /* Video buffer addresses */
>  #define VIDW_BUF_START(_buff)                  (0xA0 + ((_buff) * 8))
> +#define VIDW_BUF_START_S(_buff)                        (0x40A0 + ((_buff) * 8))
>  #define VIDW_BUF_START1(_buff)                 (0xA4 + ((_buff) * 8))
>  #define VIDW_BUF_END(_buff)                    (0xD0 + ((_buff) * 8))
>  #define VIDW_BUF_END1(_buff)                   (0xD4 + ((_buff) * 8))
> --
> 1.8.0
>
> _______________________________________________
> dri-devel mailing list
> dri-devel at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/dri-devel