linux-kernel - Re: [PATCH v1 1/1] drm/mediatek: fix CCORR mtk_ctm_s31_32_to_s1

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] [day] [month] [year] [list]

Message-ID: <CAAOTY_8awo9B857BRdgNoh_350VHa8eTaxh0ALWbT287ZNstAw@mail.gmail.com>
Date: Tue, 18 Nov 2025 13:50:05 +0000
From: Chun-Kuang Hu <chunkuang.hu@...nel.org>
To: Jay Liu <jay.liu@...iatek.com>
Cc: Chun-Kuang Hu <chunkuang.hu@...nel.org>, Philipp Zabel <p.zabel@...gutronix.de>, 
	David Airlie <airlied@...il.com>, Simona Vetter <simona@...ll.ch>, 
	Matthias Brugger <matthias.bgg@...il.com>, 
	AngeloGioacchino Del Regno <angelogioacchino.delregno@...labora.com>, 
	Yongqiang Niu <yongqiang.niu@...iatek.com>, CK Hu <ck.hu@...iatek.com>, 
	Hsin-Yi Wang <hsinyi@...omium.org>, dri-devel@...ts.freedesktop.org, 
	linux-mediatek@...ts.infradead.org, linux-kernel@...r.kernel.org, 
	linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH v1 1/1] drm/mediatek: fix CCORR mtk_ctm_s31_32_to_s1_n
 function issue

Hi, Jay:

Jay Liu <jay.liu@...iatek.com> 於 2025年9月21日 週日 上午5:55寫道：
>
> if matrixbit is 11,
> The range of color matrix is from 0 to (BIT(12) - 1).
> Values from 0 to (BIT(11) - 1) represent positive numbers,
> values from BIT(11) to (BIT(12) - 1) represent negative numbers.
> For example, -1 need converted to 8191.
> so convert S31.32 to HW Q2.11 format by drm_color_ctm_s31_32_to_qm_n,
> and set int_bits to 2.
>
> Fixes: 738ed4156fba ("drm/mediatek: Add matrix_bits private data for ccorr")
> Change-Id: Icb2aae1dee21d9ea34f263a54850fee26d97d455

With some fixed up, applied to mediatek-drm-next [1], thanks.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/chunkuang.hu/linux.git/log/?h=mediatek-drm-next

Regards,
Chun-Kuang.

> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@...labora.com>
> Signed-off-by: Jay Liu <jay.liu@...iatek.com>
> ---
>  drivers/gpu/drm/mediatek/mtk_disp_ccorr.c | 26 +++--------------------
>  1 file changed, 3 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ccorr.c b/drivers/gpu/drm/mediatek/mtk_disp_ccorr.c
> index 10d60d2c2a56..634b31346921 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_ccorr.c
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_ccorr.c
> @@ -80,28 +80,7 @@ void mtk_ccorr_stop(struct device *dev)
>         writel_relaxed(0x0, ccorr->regs + DISP_CCORR_EN);
>  }
>
> -/* Converts a DRM S31.32 value to the HW S1.n format. */
> -static u16 mtk_ctm_s31_32_to_s1_n(u64 in, u32 n)
> -{
> -       u16 r;
> -
> -       /* Sign bit. */
> -       r = in & BIT_ULL(63) ? BIT(n + 1) : 0;
> -
> -       if ((in & GENMASK_ULL(62, 33)) > 0) {
> -               /* identity value 0x100000000 -> 0x400(mt8183), */
> -               /* identity value 0x100000000 -> 0x800(mt8192), */
> -               /* if bigger this, set it to max 0x7ff. */
> -               r |= GENMASK(n, 0);
> -       } else {
> -               /* take the n+1 most important bits. */
> -               r |= (in >> (32 - n)) & GENMASK(n, 0);
> -       }
> -
> -       return r;
> -}
> -
> -void mtk_ccorr_ctm_set(struct device *dev, struct drm_crtc_state *state)
> +bool mtk_ccorr_ctm_set(struct device *dev, struct drm_crtc_state *state)
>  {
>         struct mtk_disp_ccorr *ccorr = dev_get_drvdata(dev);
>         struct drm_property_blob *blob = state->ctm;
> @@ -109,6 +88,7 @@ void mtk_ccorr_ctm_set(struct device *dev, struct drm_crtc_state *state)
>         const u64 *input;
>         uint16_t coeffs[9] = { 0 };
>         int i;
> +       int int_bits = 2;
>         struct cmdq_pkt *cmdq_pkt = NULL;
>         u32 matrix_bits = ccorr->data->matrix_bits;
>
> @@ -119,7 +99,7 @@ void mtk_ccorr_ctm_set(struct device *dev, struct drm_crtc_state *state)
>         input = ctm->matrix;
>
>         for (i = 0; i < ARRAY_SIZE(coeffs); i++)
> -               coeffs[i] = mtk_ctm_s31_32_to_s1_n(input[i], matrix_bits);
> +               coeffs[i] = drm_color_ctm_s31_32_to_qm_n(input[i], int_bits, matrix_bits);
>
>         mtk_ddp_write(cmdq_pkt, coeffs[0] << 16 | coeffs[1],
>                       &ccorr->cmdq_reg, ccorr->regs, DISP_CCORR_COEF_0);
> --
> 2.46.0
>