Re: [PATCH v2 1/5] drm/exynos: mixer: refactor layer setup

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

Hi Tobias,

2015년 11월 23일 01:09에 Tobias Jakobi 이(가) 쓴 글:
> First step in allowing a more generic way to setup complex
> blending for the different layers.
> 
> Signed-off-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
> ---
>  drivers/gpu/drm/exynos/exynos_mixer.c | 84 ++++++++++++++++++++++++++++++-----
>  1 file changed, 73 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/gpu/drm/exynos/exynos_mixer.c b/drivers/gpu/drm/exynos/exynos_mixer.c
> index 7498c6e..2c1cea3 100644
> --- a/drivers/gpu/drm/exynos/exynos_mixer.c
> +++ b/drivers/gpu/drm/exynos/exynos_mixer.c
> @@ -63,6 +63,11 @@ struct mixer_resources {
>  	struct clk		*mout_mixer;
>  };
>  
> +struct layer_cfg {
> +	unsigned int index;
> +	unsigned int priority;
> +};
> +
>  enum mixer_version_id {
>  	MXR_VER_0_0_0_16,
>  	MXR_VER_16_0_33_0,
> @@ -92,6 +97,8 @@ struct mixer_context {
>  	struct drm_device	*drm_dev;
>  	struct exynos_drm_crtc	*crtc;
>  	struct exynos_drm_plane	planes[MIXER_WIN_NR];
> +	const struct layer_cfg	*layer_cfg;
> +	unsigned int		num_layer;
>  	int			pipe;
>  	unsigned long		flags;
>  	bool			interlace;
> @@ -110,6 +117,34 @@ struct mixer_drv_data {
>  	bool					has_sclk;
>  };
>  
> +/*
> + * The default layer priorities for non-VP (video processor)
> + * and VP mixer configurations.
> + *
> + * A higher priority means that the layer is at the top of
> + * the layer stack.
> + * Configurations have to be specified with its entries
> + * sorted with increasing priority.
> + *
> + * The default config assumes the following usage scenario:
> + * layer1: OSD [top]
> + * layer0: main framebuffer
> + * video layer: video overlay [bottom]
> + * Note that the video layer is only usable when the
> + * VP is available.
> + */
> +
> +static const struct layer_cfg nonvp_default_cfg[] = {
> +	{ .index = 0, .priority = 1 },		/* layer0 */
> +	{ .index = 1, .priority = 2 },		/* layer1 */
> +};
> +
> +static const struct layer_cfg vp_default_cfg[] = {
> +	{ .index = 2, .priority = 1 },		/* video layer */
> +	{ .index = 0, .priority = 2 },		/* layer0 */
> +	{ .index = 1, .priority = 3 },		/* layer1 */
> +};
> +
>  static const u8 filter_y_horiz_tap8[] = {
>  	0,	-1,	-1,	-1,	-1,	-1,	-1,	-1,
>  	-1,	-1,	-1,	-1,	-1,	0,	0,	0,
> @@ -268,6 +303,34 @@ static void vp_default_filter(struct mixer_resources *res)
>  		filter_cr_horiz_tap4, sizeof(filter_cr_horiz_tap4));
>  }
>  
> +static void mixer_layer_priority(struct mixer_context *ctx)
> +{
> +	u32 val = 0;
> +	unsigned int i, priority;
> +
> +	for (i = 0; i < ctx->num_layer; ++i) {
> +		priority = ctx->layer_cfg[i].priority;
> +		BUG_ON(priority > 15);

What doesn constant, 15 mean? You need to clarify the meaning
and please, use a macro instead.
And it'd better to just return in this case so that the layer
configuration can be set with a default value.
I think it'd be enough to print out warning message.

Thanks,
Inki Dae

> +
> +		switch (ctx->layer_cfg[i].index) {
> +		case 0:
> +			val |= MXR_LAYER_CFG_GRP0_VAL(priority);
> +			break;
> +		case 1:
> +			val |= MXR_LAYER_CFG_GRP1_VAL(priority);
> +			break;
> +		case 2:
> +			val |= MXR_LAYER_CFG_VP_VAL(priority);
> +			break;
> +		default:
> +			BUG_ON(true);
> +			break;
> +		}
> +	}
> +
> +	mixer_reg_write(&ctx->mixer_res, MXR_LAYER_CFG, val);
> +}
> +
>  static void mixer_vsync_set_update(struct mixer_context *ctx, bool enable)
>  {
>  	struct mixer_resources *res = &ctx->mixer_res;
> @@ -673,17 +736,7 @@ static void mixer_win_reset(struct mixer_context *ctx)
>  	mixer_reg_writemask(res, MXR_STATUS, MXR_STATUS_16_BURST,
>  		MXR_STATUS_BURST_MASK);
>  
> -	/* setting default layer priority: layer1 > layer0 > video
> -	 * because typical usage scenario would be
> -	 * layer1 - OSD
> -	 * layer0 - framebuffer
> -	 * video - video overlay
> -	 */
> -	val = MXR_LAYER_CFG_GRP1_VAL(3);
> -	val |= MXR_LAYER_CFG_GRP0_VAL(2);
> -	if (ctx->vp_enabled)
> -		val |= MXR_LAYER_CFG_VP_VAL(1);
> -	mixer_reg_write(res, MXR_LAYER_CFG, val);
> +	mixer_layer_priority(ctx);
>  
>  	/* setting background color */
>  	mixer_reg_write(res, MXR_BG_COLOR0, 0x008080);
> @@ -1209,6 +1262,15 @@ static int mixer_probe(struct platform_device *pdev)
>  	ctx->vp_enabled = drv->is_vp_enabled;
>  	ctx->has_sclk = drv->has_sclk;
>  	ctx->mxr_ver = drv->version;
> +
> +	if (drv->is_vp_enabled) {
> +		ctx->layer_cfg = vp_default_cfg;
> +		ctx->num_layer = ARRAY_SIZE(vp_default_cfg);
> +	} else {
> +		ctx->layer_cfg = nonvp_default_cfg;
> +		ctx->num_layer = ARRAY_SIZE(nonvp_default_cfg);
> +	}
> +
>  	init_waitqueue_head(&ctx->wait_vsync_queue);
>  	atomic_set(&ctx->wait_vsync_event, 0);
>  
>