From nobody Mon Apr 6 19:59:50 2026 Received: from mail-4322.protonmail.ch (mail-4322.protonmail.ch [185.70.43.22]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8297A354AF2 for ; Wed, 18 Mar 2026 07:33:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.70.43.22 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773819185; cv=none; b=YvdV6ZM1qwgJUrTHnFX0z/vnGmBsfD5tVPNDrlPH/IlplyjRIyiNIvRgtX1aUeNXkYfntYpqVkxmOXJW6wSQ3Ky+uzLo3wvQ7iBPKQx9owrVjmAOZDep7YXMJDiuf1XKrs8UMkcV0y39/2CR4/FjeWDzTGRpCQQlsN16dmeT2tc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773819185; c=relaxed/simple; bh=Wy7pmybLcN2EzDYfooh+oiFyI7YbhcMFju9H5ENgtVI=; h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=trWoyO7xIX6phraJdURj21yW7MELMlBl7wCfAfIAqgRbfqmvKJadRno9LUFM8w+0XX5ExXPEPLeiC+bceOIL6IY/qj1xi50HKziRAklmZVjHdQdpxSi2nfQmH+q+3pL5QdU9QkmRr7hC3x9whiSeF0a8zwKS3Pc1/8qH2EKNE/k= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=pm.me; spf=pass smtp.mailfrom=pm.me; dkim=pass (2048-bit key) header.d=pm.me header.i=@pm.me header.b=Y2LADrkC; arc=none smtp.client-ip=185.70.43.22 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=pm.me Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pm.me Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=pm.me header.i=@pm.me header.b="Y2LADrkC" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pm.me; s=protonmail3; t=1773819182; x=1774078382; bh=Wy7pmybLcN2EzDYfooh+oiFyI7YbhcMFju9H5ENgtVI=; h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: Feedback-ID:From:To:Cc:Date:Subject:Reply-To:Feedback-ID: Message-ID:BIMI-Selector; b=Y2LADrkCf8lllWlZ9vKGIPTzW8ZRniVnXdoqByJztTOKg4HhBQBqZhPuhVv1Io7cq IPBF7C53yR1e2YC/g/eOFWjlJKkDTOryK1T4bHI3ApXPrCGtfD3T4gUAOTJ4wATmQH +piLr85kuSZY5rL0erFA487BND7Du9XQYsC0EBgMSMXKzLfmYL6ZT00BxREGODjh1/ 4B8LHcPjmw17IlniRdJbPjDpNSp831gO23mu1kt/nUi2TLyjNys2ScUkLm4cdny23w 5C/93nUpWMjOHvn1IiGiju74r8Op7SIpj/rv5ryDre+kg15+GFgs0IKa67fq5BceHC ayu+E3Kn/R/OA== Date: Wed, 18 Mar 2026 07:32:58 +0000 To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Rob Clark , Dmitry Baryshkov , Abhinav Kumar , Jessica Zhang , Sean Paul , Marijn Suijten From: Alexander Koskovich Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org, Alexander Koskovich Subject: [PATCH 1/2] drm/mipi-dsi: add flag for sending all DSC slices in one packet Message-ID: <20260318-dsi-dsc-slice-per-pkt-v1-1-1bd66b7f9e0c@pm.me> In-Reply-To: <20260318-dsi-dsc-slice-per-pkt-v1-0-1bd66b7f9e0c@pm.me> References: <20260318-dsi-dsc-slice-per-pkt-v1-0-1bd66b7f9e0c@pm.me> Feedback-ID: 37836894:user:proton X-Pm-Message-ID: e025ce9a6b601b1cd23397e38e9cee7c0f03c5db Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" The MIPI DSI v1.3 spec defines two modes for transporting compressed pixel data: one slice per packet or multiple slice widths in a single packet (Section 8.8.24 Figure 40). Add a MIPI_DSI_MODE_DSC_ALL_SLICES_IN_PKT flag that panel drivers can set to indicate that all DSC slices for a line should be packed into a single packet. When unset should default to 1 slice per packet. Signed-off-by: Alexander Koskovich Reviewed-by: Dmitry Baryshkov --- include/drm/drm_mipi_dsi.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h index 3aba7b380c8d..d3ad8c5d3ebe 100644 --- a/include/drm/drm_mipi_dsi.h +++ b/include/drm/drm_mipi_dsi.h @@ -138,6 +138,8 @@ struct mipi_dsi_host *of_find_mipi_dsi_host_by_node(str= uct device_node *node); #define MIPI_DSI_MODE_LPM BIT(11) /* transmit data ending at the same time for all lanes within one hsync */ #define MIPI_DSI_HS_PKT_END_ALIGNED BIT(12) +/* pack all DSC slices for a line into a single packet */ +#define MIPI_DSI_MODE_DSC_ALL_SLICES_IN_PKT BIT(13) =20 enum mipi_dsi_pixel_format { MIPI_DSI_FMT_RGB888, --=20 2.53.0 From nobody Mon Apr 6 19:59:50 2026 Received: from mail-43100.protonmail.ch (mail-43100.protonmail.ch [185.70.43.100]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A283F354AF2 for ; Wed, 18 Mar 2026 07:33:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.70.43.100 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773819189; cv=none; b=dTYs1e8YenQiWAiHjhb7pzZKqDuEBHtyH/75U8JCy1IS4WWm/SCNH46goFGSVpArI+8AkbA4Z6e1Ts58dZObV2khTtKF12j5Ztl8dr8BZ0pGTjuXoPWDgaB+wzRzAEfI+lO9UXSojSlacIAwn+OgoAZoG4WoweTqgUYAxt2eSXM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773819189; c=relaxed/simple; bh=nosWJtdJO+rItmKOlIOhbi7d9qOwJndqlYLazOCdtkg=; h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=G1ZG0eeHLZKnAm7jDmp6aMLJqCBqjyha6WO6pGMl+BJE7YV+67pcf5eoHLehE25srJ0+D9ispvPAiPd7Swhv+DCzcnYU7FWIx/rNzckmpQYe8RObbHA9z+I+z8QhzuBOXt+uHrpWTAspfm60cD99D0iEYta08GbsW6eT7cNMdCU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=pm.me; spf=pass smtp.mailfrom=pm.me; dkim=pass (2048-bit key) header.d=pm.me header.i=@pm.me header.b=dkqfPUl3; arc=none smtp.client-ip=185.70.43.100 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=pm.me Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pm.me Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=pm.me header.i=@pm.me header.b="dkqfPUl3" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pm.me; s=protonmail3; t=1773819186; x=1774078386; bh=HEEHya28D9AzgK7IMREp/bxt0n4mna9PaQwrUvZ8aHg=; h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: Feedback-ID:From:To:Cc:Date:Subject:Reply-To:Feedback-ID: Message-ID:BIMI-Selector; b=dkqfPUl3ZNRqI4GJi21Sqga9kiHiY2bb89QmGr9t+4t3A9lWc0F4Z12X6tuRYTr7F j3E74ff2LTOGuGuRY95XcBUAsgo+KkGIxyFdfV83PKSe11sOFq266YVWc+7x7XBRbw DiJnOu/0uaepLD34uvEeSuqwLeIaBF6OZNJhV9iIIaeFDuq8wuT0NWwG4bq97fHkIf cqLTEReBFlLVf7L8xawBwEWcypH1U6qT4smtPHkKIa6OvIb61SymXumm5Qkh6jZuYi Btw+SSN33mJOvu04W3xXcmGmpTds5HZoIuSZSl+iiTF2QREUZ0M51ZbHCXiUfD49uW qF9fjeRhq0BFw== Date: Wed, 18 Mar 2026 07:33:03 +0000 To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Rob Clark , Dmitry Baryshkov , Abhinav Kumar , Jessica Zhang , Sean Paul , Marijn Suijten From: Alexander Koskovich Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org, Alexander Koskovich Subject: [PATCH 2/2] drm/msm/dsi: support DSC configurations with slice_per_pkt > 1 Message-ID: <20260318-dsi-dsc-slice-per-pkt-v1-2-1bd66b7f9e0c@pm.me> In-Reply-To: <20260318-dsi-dsc-slice-per-pkt-v1-0-1bd66b7f9e0c@pm.me> References: <20260318-dsi-dsc-slice-per-pkt-v1-0-1bd66b7f9e0c@pm.me> Feedback-ID: 37836894:user:proton X-Pm-Message-ID: da70dc4b6326ffeb32679cd1fe636db6e5a0f639 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Some panels support multiple slice to be sent in a single DSC packet and this feature is a must for specific panels, such as the JDI LPM026M648C. Use the MIPI_DSI_MODE_DSC_ALL_SLICES_IN_PKT flag to derive slice_per_pkt from slice_count, note that most panels are expected to just work with just one slice per packet. This change was originally authored by Jonathan Marek: https://lore.kernel.org/all/20231114174218.19765-3-jonathan@marek.ca Signed-off-by: Alexander Koskovich --- drivers/gpu/drm/msm/dsi/dsi_host.c | 25 ++++++++++--------------- 1 file changed, 10 insertions(+), 15 deletions(-) diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/d= si_host.c index db6da99375a1..758b076ee4bf 100644 --- a/drivers/gpu/drm/msm/dsi/dsi_host.c +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c @@ -166,6 +166,7 @@ struct msm_dsi_host { =20 struct drm_display_mode *mode; struct drm_dsc_config *dsc; + unsigned int dsc_slice_per_pkt; =20 /* connected device info */ unsigned int channel; @@ -927,17 +928,10 @@ static void dsi_update_dsc_timing(struct msm_dsi_host= *msm_host, bool is_cmd_mod slice_per_intf =3D dsc->slice_count; =20 total_bytes_per_intf =3D dsc->slice_chunk_size * slice_per_intf; - bytes_per_pkt =3D dsc->slice_chunk_size; /* * slice_per_pkt; */ + bytes_per_pkt =3D dsc->slice_chunk_size * msm_host->dsc_slice_per_pkt; =20 eol_byte_num =3D total_bytes_per_intf % 3; - - /* - * Typically, pkt_per_line =3D slice_per_intf * slice_per_pkt. - * - * Since the current driver only supports slice_per_pkt =3D 1, - * pkt_per_line will be equal to slice per intf for now. - */ - pkt_per_line =3D slice_per_intf; + pkt_per_line =3D slice_per_intf / msm_host->dsc_slice_per_pkt; =20 if (is_cmd_mode) /* packet data type */ reg =3D DSI_COMMAND_COMPRESSION_MODE_CTRL_STREAM0_DATATYPE(MIPI_DSI_DCS_= LONG_WRITE); @@ -1088,12 +1082,8 @@ static void dsi_timing_setup(struct msm_dsi_host *ms= m_host, bool is_bonded_dsi) else /* * When DSC is enabled, WC =3D slice_chunk_size * slice_per_pkt + 1. - * Currently, the driver only supports default value of slice_per_pkt = =3D 1 - * - * TODO: Expand mipi_dsi_device struct to hold slice_per_pkt info - * and adjust DSC math to account for slice_per_pkt. */ - wc =3D msm_host->dsc->slice_chunk_size + 1; + wc =3D msm_host->dsc->slice_chunk_size * msm_host->dsc_slice_per_pkt + = 1; =20 dsi_write(msm_host, REG_DSI_CMD_MDP_STREAM0_CTRL, DSI_CMD_MDP_STREAM0_CTRL_WORD_COUNT(wc) | @@ -1702,8 +1692,13 @@ static int dsi_host_attach(struct mipi_dsi_host *hos= t, msm_host->lanes =3D dsi->lanes; msm_host->format =3D dsi->format; msm_host->mode_flags =3D dsi->mode_flags; - if (dsi->dsc) + if (dsi->dsc) { msm_host->dsc =3D dsi->dsc; + if (dsi->mode_flags & MIPI_DSI_MODE_DSC_ALL_SLICES_IN_PKT) + msm_host->dsc_slice_per_pkt =3D dsi->dsc->slice_count; + else + msm_host->dsc_slice_per_pkt =3D 1; + } =20 ret =3D dsi_dev_attach(msm_host->pdev); if (ret) --=20 2.53.0