From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1CE54606A326 for ; Thu, 5 Nov 2026 08:59:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=SIyCfcaf; dkim=pass (2048-bit key, unprotected) header.d=collabora.com header.i=@collabora.com header.a=rsa-sha256 header.s=mail header.b=D8hkm7cL DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Unsubscribe-Post: List-Owner; bh=bBn1ykyRQWqMly5VMYEBKX4QjwJ5XVSM4rfTKbZt6Os=; b=SIyCfcafgIOjuK oFhs+25MSGvnndndHzAHAWcEzLGVOkRb2DiFq8J37nK1JMB9CGQU/h5pRB5mW6Gh2rrzWJ4SCdZKW 1QzYviV0mvHIUnHL60fTSVevjo2nCsyRMMX3cuP4xxzhqHJocAuXq/cuRhOIc9xfR1yj+EguTSuC/ 4ftNwtus4PL/nAlGoaXV80Cmfgjj4FUYQjPvFKVbaqD3aRTUaz+VqZ1BMT8fYbgBTFi52+BwOxcl1 sZqMbbc0C4BgsBL+4e9hqxl84WFWwBcxMGNSwMayGDXpUSRg20LWUefNuBPU8adtXJYRssOYNa7Wp XgnS6deex0CZakfr64Uw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xOtJd-00000008Dv3-3Zha; Thu, 05 Nov 2026 08:59:25 +0000 Received: from bali.collaboradmins.com ([148.251.105.195]) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xOtJb-00000008Dtz-1PVt; Thu, 05 Nov 2026 08:59:25 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1793869160; bh=ZKaZFFHipOBBEL4aN3JZCurDbr471IQ5mAHx+yt6YDI=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=D8hkm7cLJ7S+YmF4PZLUoJwECskt1Lx2wBGPwMxKGB7U+y+B1ib+bRRjrhTYsxFfw uIHzv5kGUcdqzY7GQvciwIRUnjE6E1bjhIAm02/rvqjKZ4cMuSbwVViK78+8ioi4mp eds24T+OXz4w10VRzgrjCm/MNXaYzxHaTm/CjNuYotXypSNeel73uJThZZWhRkrGHb zYQghiYqQPaW8FT/Oc+6gAA7+/0J7UQTy9aPUips21sAW2f9qfwXovX73eEfDlXyK2 qEJkPV5RCAnKVk4ouAglPbYCYECNTQKSLvYyyHXgWUEYrEZ4891C0BvrPwQ6SfXsc0 LF7orzWiVgBsQ== Received: from [100.64.1.21] (unknown [100.64.1.21]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange x25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: kholk11) by bali.collaboradmins.com (Postfix) with ESMTPSA id 50DF617E05D6; Thu, 05 Nov 2026 09:59:19 +0100 (CET) Message-ID: Date: Thu, 5 Nov 2026 09:59:18 +0100 X-Archived-By: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v9 02/13] drm/mediatek: Implement Display Stream Compression support To: Roman Vivchar , chunkuang.hu@kernel.org Cc: p.zabel@pengutronix.de, maarten.lankhorst@linux.intel.com, mripard@kernel.org, tzimmermann@suse.de, airlied@gmail.com, simona@ffwll.ch, robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org, matthias.bgg@gmail.com, jitao.shi@mediatek.com, dri-devel@lists.freedesktop.org, linux-mediatek@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kernel@collabora.com, justin.yeh@mediatek.com, jason-jh.lin@mediatek.com References: <8fcdd2fa-7c9c-4af5-a7b4-45fb881d88a8@protonmail.com> From: AngeloGioacchino Del Regno Content-Language: en-US In-Reply-To: <8fcdd2fa-7c9c-4af5-a7b4-45fb881d88a8@protonmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261105_005923_987688_EE4F0550 X-CRM114-Status: GOOD ( 27.12 ) X-Spam-Score: -2.1 (--) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-17.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On 11/4/26 19:51, Roman Vivchar wrote: > Hi Angelo, > > I have tested this series with my out-of-tree mt6595 (command mode > panel) and mt6768 (video mode) DRM. There's no regressions, but I > spotted an issue with kconfig. > > On 9/16/26 14:08, AngeloGioacchino Del Regno wrote: >> Add a real driver for the Display Stream Compression (DSC) Display >> Controller IP, implementing support for DSC v1.1 to v1.2. >> >> In order to do this, it was necessary to remove the basic DSC IP >> bypass setup from mtk_ddp_comp: this functionality is retained in >> the new mtk_disp_dsc driver, which checks if DSC was actually >> requested by other components (with the only one that currently >> supports this being DSI) and, if not, it will set BYPASS mode in >> the DSC IP. >> >> Like before, the BYPASS mode is set before starting the DSC IP, >> but unlike before, this is being done in the component start >> callback instead of the config one. >> Notably, the config callback is called by mtk_crtc always >> immediately before the calling start callback, so the order of >> register writes is retained. >> The only real difference is that now this is being done through >> CPU writes instead of CMDQ, but since that's called only once >> and since it's just three registers, the performance impact will >> not be minimal and not even measurable. >> >> As anticipated, DSC handling was also introduced in the mtk_dsi >> driver: when performing dsi_host_attach, the driver now checks >> if the DSI panel adds the DSC configuration structure to the >> mipi_dsi_device structure and, if it does, it will store a >> pointer in the driver-local mtk_dsi structure's `dsc` member. >> >> The DSI driver will then check whether the DSC configuration >> that comes from the panel is valid (in regard to MediaTek DSI) >> and will call the DRM API's DSC helpers to calculate and set >> all of the const and RC parameters for the actual DSC setup. >> >> For the time being, even though the latest MediaTek SoCs do >> support DSC v1.2, only DSC v1.1 pre-scr support is implemented >> as an initial contribution (which is rather big, and 1.2 would >> make it even bigger - but that can anyway be implemented later). >> >> As a last step for validation of DSC parameters in DSI, a check >> for the hdisplay against DSC slice sidth and one for vdisplay >> against DSC slice height was added to the mode_valid callback, >> making sure that H/V are, as expected, multiples of slice W/H. >> >> Signed-off-by: AngeloGioacchino Del Regno > > ... > >> --- a/drivers/gpu/drm/mediatek/mtk_dsi.c >> +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c >> @@ -18,6 +18,8 @@ >> #include