linux-kernel - Re: [PATCH v7 12/18] drm/mediatek: Support "Pre-multiplied" blending in Mixer

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <86db6c04cf2e3873232c93f8c7d33814a1a42edd.camel@mediatek.com>
Date: Fri, 3 May 2024 09:28:52 +0000
From: CK Hu (胡俊光) <ck.hu@...iatek.com>
To: Shawn Sung (宋孝謙) <Shawn.Sung@...iatek.com>,
	"chunkuang.hu@...nel.org" <chunkuang.hu@...nel.org>,
	"angelogioacchino.delregno@...labora.com"
	<angelogioacchino.delregno@...labora.com>
CC: "linux-mediatek@...ts.infradead.org" <linux-mediatek@...ts.infradead.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	Bibby Hsieh (謝濟遠) <Bibby.Hsieh@...iatek.com>,
	"jason-ch.chen@...iatek.corp-partner.google.com"
	<jason-ch.chen@...iatek.corp-partner.google.com>,
	Nancy Lin (林欣螢) <Nancy.Lin@...iatek.com>,
	"daniel@...ll.ch" <daniel@...ll.ch>, "p.zabel@...gutronix.de"
	<p.zabel@...gutronix.de>, "dri-devel@...ts.freedesktop.org"
	<dri-devel@...ts.freedesktop.org>, "airlied@...il.com" <airlied@...il.com>,
	"sean@...rly.run" <sean@...rly.run>, "matthias.bgg@...il.com"
	<matthias.bgg@...il.com>, "fshao@...omium.org" <fshao@...omium.org>,
	"linux-arm-kernel@...ts.infradead.org" <linux-arm-kernel@...ts.infradead.org>
Subject: Re: [PATCH v7 12/18] drm/mediatek: Support "Pre-multiplied" blending
 in Mixer

Hi, Shawn:

On Thu, 2024-05-02 at 18:38 +0800, Shawn Sung wrote:
> From: Hsiao Chien Sung <shawn.sung@...iatek.com>
> 
> Support "Pre-multiplied" alpha blending mode in Mixer.
> Before this patch, only the coverage mode is supported.
> 
> Signed-off-by: Hsiao Chien Sung <shawn.sung@...iatek.com>
> ---
>  drivers/gpu/drm/mediatek/mtk_ethdr.c | 15 ++++++++++-----
>  1 file changed, 10 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_ethdr.c
> b/drivers/gpu/drm/mediatek/mtk_ethdr.c
> index 5283e0993ed65..4f043be21ee36 100644
> --- a/drivers/gpu/drm/mediatek/mtk_ethdr.c
> +++ b/drivers/gpu/drm/mediatek/mtk_ethdr.c
> @@ -5,6 +5,7 @@
>  
>  #include <drm/drm_fourcc.h>
>  #include <drm/drm_framebuffer.h>
> +#include <drm/drm_blend.h>
>  #include <linux/clk.h>
>  #include <linux/component.h>
>  #include <linux/of.h>
> @@ -35,6 +36,7 @@
>  #define MIX_SRC_L0_EN				BIT(0)
>  #define MIX_L_SRC_CON(n)		(0x28 + 0x18 * (n))
>  #define NON_PREMULTI_SOURCE			(2 << 12)
> +#define PREMULTI_SOURCE				(3 << 12)
>  #define MIX_L_SRC_SIZE(n)		(0x30 + 0x18 * (n))
>  #define MIX_L_SRC_OFFSET(n)		(0x34 + 0x18 * (n))
>  #define MIX_FUNC_DCM0			0x120
> @@ -153,7 +155,7 @@ void mtk_ethdr_layer_config(struct device *dev,
> unsigned int idx,
>  	struct mtk_plane_pending_state *pending = &state->pending;
>  	unsigned int offset = (pending->x & 1) << 31 | pending->y << 16
> | pending->x;
>  	unsigned int align_width = ALIGN_DOWN(pending->width, 2);
> -	unsigned int alpha_con = 0;
> +	unsigned int mix_con = 0;
>  	bool replace_src_a = false;
>  
>  	dev_dbg(dev, "%s+ idx:%d", __func__, idx);
> @@ -171,8 +173,12 @@ void mtk_ethdr_layer_config(struct device *dev,
> unsigned int idx,
>  		return;
>  	}
>  
> -	if (state->base.fb && state->base.fb->format->has_alpha)
> -		alpha_con = MIXER_ALPHA_AEN | MIXER_ALPHA;
> +	mix_con |= MIXER_ALPHA_AEN | (state->base.alpha & MIXER_ALPHA);

This looks like plane alpha (the whole video plane use single alpha
value), not related to pre-multiplied blending, so separate this to
another patch.

For no alpha format, you change the setting. If this is bug fix, add
fixes tag.

> +
> +	if (state->base.pixel_blend_mode != DRM_MODE_BLEND_COVERAGE)
> +		mix_con |= PREMULTI_SOURCE;
> +	else
> +		mix_con |= NON_PREMULTI_SOURCE;
>  
>  	if (state->base.fb && !state->base.fb->format->has_alpha) {
>  		/*
> @@ -189,8 +195,7 @@ void mtk_ethdr_layer_config(struct device *dev,
> unsigned int idx,
>  	mtk_ddp_write(cmdq_pkt, pending->height << 16 | align_width,
> &mixer->cmdq_base,
>  		      mixer->regs, MIX_L_SRC_SIZE(idx));
>  	mtk_ddp_write(cmdq_pkt, offset, &mixer->cmdq_base, mixer->regs, 
> MIX_L_SRC_OFFSET(idx));
> -	mtk_ddp_write_mask(cmdq_pkt, alpha_con, &mixer->cmdq_base,
> mixer->regs, MIX_L_SRC_CON(idx),
> -			   0x1ff);
> +	mtk_ddp_write(cmdq_pkt, mix_con, &mixer->cmdq_base, mixer-
> >regs, MIX_L_SRC_CON(idx));
>  	mtk_ddp_write_mask(cmdq_pkt, BIT(idx), &mixer->cmdq_base,
> mixer->regs, MIX_SRC_CON,
>  			   BIT(idx));
>  }