From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from new4-smtp.messagingengine.com (new4-smtp.messagingengine.com [66.111.4.230]) (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 55ADF20F8 for ; Wed, 7 Sep 2022 14:34:28 +0000 (UTC) Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailnew.nyi.internal (Postfix) with ESMTP id 1F2A25804F0; Wed, 7 Sep 2022 10:34:27 -0400 (EDT) Received: from mailfrontend1 ([10.202.2.162]) by compute3.internal (MEProxy); Wed, 07 Sep 2022 10:34:27 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cerno.tech; h=cc :cc:content-type:date:date:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:sender:subject :subject:to:to; s=fm2; t=1662561267; x=1662568467; bh=JgmI+KGSUN 45Wie/3+bjGkbyz5oOCqNiJe6kdug5myc=; b=fEOSeRjgEOD6B/j91iz7LAm2nV zm9is7Er/ViHIxBpgpZb6lwibFClewD+iIDcvBDRp+1lmhPCyaLqGg7IA7cP8Xoc wuPl4RWLG7DFN/l8Ef3DsxfT1cd2zQLRfIYCirzpNWoWvJn1u1DHeJKGdSUDI28z 1jY0sVontbTSiey/BmEiACSSDUwkweDEP8Y88zWm/rexWHXi4G8cMuE0k+2Ubav8 yVcnkHbvjTtEanw7DdeSQbMbBEQZUlGAaHFddXqW8+k9yjnOhCF7l9h878Ua8DYW sgayo4HxqN7j7DCzmcPR4NNETP7WQrV7L9DlqdV2OvKcqO+2mZ+6pYjLKaNA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:date:date:feedback-id :feedback-id:from:from:in-reply-to:in-reply-to:message-id :mime-version:references:reply-to:sender:subject:subject:to:to :x-me-proxy:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s= fm2; t=1662561267; x=1662568467; bh=JgmI+KGSUN45Wie/3+bjGkbyz5oO CqNiJe6kdug5myc=; b=QZsve74EP24R9KWs9WZsCIVkxBNujxPG60TN9puqze3c o6aNhrxKdPVbGh09EQgmTIu30mCjSkY9oBqwNWg3cRbVT9CSGDTSlxglGLwGruZV vARWixq4SBADNaeBNbJTGCIG9odD6/9WAWxTk4aOKFPICop9IO3pcwWu9wND5de0 WZ78qWyg0sbruHsLAn0/vTLXw7MuMI08liDizfiz6oJ2b/8T5ZAp2EpYm9J/sOJe 0O49dbliLK8gjn2pXV+ferzud7lC4N6BLE7ZvbYFTFT4O8aQGL1u1rHr3lvb7iPF JbqQ9W8hlaP3qBDs1foUJk1yTi+UzY3FpobNfifkdg== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvfedrfedttddgjeejucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhepfffhvfevuffkfhggtggujgesghdtreertddtudenucfhrhhomhepofgrgihi mhgvucftihhprghrugcuoehmrgigihhmvgestggvrhhnohdrthgvtghhqeenucggtffrrg htthgvrhhnpeejveefheefkeeiffegveelveetgffffeektdefuefhtedtgeejhefggedu ffffudenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpe hmrgigihhmvgestggvrhhnohdrthgvtghh X-ME-Proxy: Feedback-ID: i8771445c:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Wed, 7 Sep 2022 10:34:24 -0400 (EDT) Date: Wed, 7 Sep 2022 16:34:21 +0200 From: Maxime Ripard To: Mateusz Kwiatkowski Cc: Ben Skeggs , David Airlie , Chen-Yu Tsai , Thomas Zimmermann , Jani Nikula , Lyude Paul , Philipp Zabel , Maarten Lankhorst , Rodrigo Vivi , Tvrtko Ursulin , Jernej Skrabec , Samuel Holland , Karol Herbst , Noralf =?utf-8?Q?Tr=C3=B8nnes?= , Emma Anholt , Daniel Vetter , Joonas Lahtinen , Hans de Goede , linux-arm-kernel@lists.infradead.org, Phil Elwell , intel-gfx@lists.freedesktop.org, Dave Stevenson , dri-devel@lists.freedesktop.org, Dom Cobley , linux-kernel@vger.kernel.org, nouveau@lists.freedesktop.org, linux-sunxi@lists.linux.dev, Geert Uytterhoeven Subject: Re: [PATCH v2 10/41] drm/modes: Add a function to generate analog display modes Message-ID: <20220907143421.4iopqwhp3yfircsh@houat> References: <20220728-rpi-analog-tv-properties-v2-0-459522d653a7@cerno.tech> <20220728-rpi-analog-tv-properties-v2-10-459522d653a7@cerno.tech> <242d272b-5b79-986c-9aaf-64e62f6b37ff@gmail.com> <20220905133755.gcmmntg3wnecyqjq@houat> <10ce686a-d7c8-9ce4-3979-735ad8eab3b5@gmail.com> Precedence: bulk X-Mailing-List: linux-sunxi@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="xs3njf2uogpsrjq3" Content-Disposition: inline In-Reply-To: <10ce686a-d7c8-9ce4-3979-735ad8eab3b5@gmail.com> --xs3njf2uogpsrjq3 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Sep 05, 2022 at 06:44:42PM +0200, Mateusz Kwiatkowski wrote: > Hi Maxime, >=20 > W dniu 5.09.2022 o 15:37, Maxime Ripard pisze: > >>> +=A0=A0=A0 vfp =3D vfp_min + (porches_rem / 2); > >>> +=A0=A0=A0 vbp =3D porches - vfp; > >> > >> Relative position of the vertical sync within the VBI effectively move= s the > >> image up and down. Adding that (porches_rem / 2) moves the image up of= f center > >> by that many pixels. I'd keep the VFP always at minimum to keep the im= age > >> centered. > > > > And you would increase the back porch only then? >=20 > Well, increasing vbp only gives a centered image with the default 480i/57= 6i > resolutions. However, only ever changing vbp will cause the image to be a= lways > at the bottom of the screen when the active line count is decreased (e.g. > setting the resolution to 720x480 but for 50Hz "PAL" - like many game con= soles > did back in the day). >=20 > I believe that the perfect solution would: >=20 > - Use the canonical / standard-defined blanking line counts for the stand= ard > =A0 vertical resolutions (480/486/576) > - Increase vfp and vbp from there by the same number if a smaller number = of > =A0 active lines is specified, so that the resulting image is centered > - Likewise, decrease vfp and vbp by the same number if the active line nu= mber > =A0 is larger and there is still leeway (this should allow for seamless h= andling > =A0 of 480i vs. 486i for 60 Hz "NTSC") I'm not sure I understand how that's any different than the code you initially commented on. I would start by taking the entire blanking area, remove the sync period. We only have the two porches now, and I'm starting from the minimum, adding as many pixels in both (unless it's not an even number, in which case the backporch will have the extra pixel). Isn't it the same thing? > - If even more active lines are specified, once the limit for vfp is hit,= then > =A0 decrease vbp only - the resulting image will definitely be off-center= , but > =A0 there's no other way Unless you only want me to consider the front porch maximum? Maxime --xs3njf2uogpsrjq3 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRcEzekXsqa64kGDp7j7w1vZxhRxQUCYxir7QAKCRDj7w1vZxhR xYnUAQDKFDkrZV/fLpjtD+btaCpKvPKkEUm37bnBk3TyD3SBTAD+I0kVAytjVinQ y5KTIrc3dKg0llXX1SWgrvw0OE2vMAI= =QW9g -----END PGP SIGNATURE----- --xs3njf2uogpsrjq3-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 98597C54EE9 for ; Wed, 7 Sep 2022 14:34:34 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 4EB5110E786; Wed, 7 Sep 2022 14:34:33 +0000 (UTC) Received: from new4-smtp.messagingengine.com (new4-smtp.messagingengine.com [66.111.4.230]) by gabe.freedesktop.org (Postfix) with ESMTPS id 05FC110E786; 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Wed, 7 Sep 2022 10:34:24 -0400 (EDT) Date: Wed, 7 Sep 2022 16:34:21 +0200 From: Maxime Ripard To: Mateusz Kwiatkowski Message-ID: <20220907143421.4iopqwhp3yfircsh@houat> References: <20220728-rpi-analog-tv-properties-v2-0-459522d653a7@cerno.tech> <20220728-rpi-analog-tv-properties-v2-10-459522d653a7@cerno.tech> <242d272b-5b79-986c-9aaf-64e62f6b37ff@gmail.com> <20220905133755.gcmmntg3wnecyqjq@houat> <10ce686a-d7c8-9ce4-3979-735ad8eab3b5@gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="xs3njf2uogpsrjq3" Content-Disposition: inline In-Reply-To: <10ce686a-d7c8-9ce4-3979-735ad8eab3b5@gmail.com> Subject: Re: [Nouveau] [PATCH v2 10/41] drm/modes: Add a function to generate analog display modes X-BeenThere: nouveau@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Nouveau development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: David Airlie , nouveau@lists.freedesktop.org, Joonas Lahtinen , dri-devel@lists.freedesktop.org, Phil Elwell , Emma Anholt , Samuel Holland , Jernej Skrabec , Chen-Yu Tsai , Geert Uytterhoeven , Ben Skeggs , linux-sunxi@lists.linux.dev, intel-gfx@lists.freedesktop.org, Maarten Lankhorst , Jani Nikula , Hans de Goede , Rodrigo Vivi , Daniel Vetter , linux-arm-kernel@lists.infradead.org, Tvrtko Ursulin , Dom Cobley , linux-kernel@vger.kernel.org, Noralf =?utf-8?Q?Tr=C3=B8nnes?= , Philipp Zabel Errors-To: nouveau-bounces@lists.freedesktop.org Sender: "Nouveau" --xs3njf2uogpsrjq3 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Sep 05, 2022 at 06:44:42PM +0200, Mateusz Kwiatkowski wrote: > Hi Maxime, >=20 > W dniu 5.09.2022 o 15:37, Maxime Ripard pisze: > >>> +=A0=A0=A0 vfp =3D vfp_min + (porches_rem / 2); > >>> +=A0=A0=A0 vbp =3D porches - vfp; > >> > >> Relative position of the vertical sync within the VBI effectively move= s the > >> image up and down. Adding that (porches_rem / 2) moves the image up of= f center > >> by that many pixels. I'd keep the VFP always at minimum to keep the im= age > >> centered. > > > > And you would increase the back porch only then? >=20 > Well, increasing vbp only gives a centered image with the default 480i/57= 6i > resolutions. However, only ever changing vbp will cause the image to be a= lways > at the bottom of the screen when the active line count is decreased (e.g. > setting the resolution to 720x480 but for 50Hz "PAL" - like many game con= soles > did back in the day). >=20 > I believe that the perfect solution would: >=20 > - Use the canonical / standard-defined blanking line counts for the stand= ard > =A0 vertical resolutions (480/486/576) > - Increase vfp and vbp from there by the same number if a smaller number = of > =A0 active lines is specified, so that the resulting image is centered > - Likewise, decrease vfp and vbp by the same number if the active line nu= mber > =A0 is larger and there is still leeway (this should allow for seamless h= andling > =A0 of 480i vs. 486i for 60 Hz "NTSC") I'm not sure I understand how that's any different than the code you initially commented on. I would start by taking the entire blanking area, remove the sync period. We only have the two porches now, and I'm starting from the minimum, adding as many pixels in both (unless it's not an even number, in which case the backporch will have the extra pixel). Isn't it the same thing? > - If even more active lines are specified, once the limit for vfp is hit,= then > =A0 decrease vbp only - the resulting image will definitely be off-center= , but > =A0 there's no other way Unless you only want me to consider the front porch maximum? Maxime --xs3njf2uogpsrjq3 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRcEzekXsqa64kGDp7j7w1vZxhRxQUCYxir7QAKCRDj7w1vZxhR xYnUAQDKFDkrZV/fLpjtD+btaCpKvPKkEUm37bnBk3TyD3SBTAD+I0kVAytjVinQ y5KTIrc3dKg0llXX1SWgrvw0OE2vMAI= =QW9g -----END PGP SIGNATURE----- --xs3njf2uogpsrjq3-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id CF17FC6FA86 for ; Wed, 7 Sep 2022 14:34:50 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B204D10E789; Wed, 7 Sep 2022 14:34:37 +0000 (UTC) Received: from new4-smtp.messagingengine.com (new4-smtp.messagingengine.com [66.111.4.230]) by gabe.freedesktop.org (Postfix) with ESMTPS id 05FC110E786; 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Wed, 7 Sep 2022 10:34:24 -0400 (EDT) Date: Wed, 7 Sep 2022 16:34:21 +0200 From: Maxime Ripard To: Mateusz Kwiatkowski Subject: Re: [PATCH v2 10/41] drm/modes: Add a function to generate analog display modes Message-ID: <20220907143421.4iopqwhp3yfircsh@houat> References: <20220728-rpi-analog-tv-properties-v2-0-459522d653a7@cerno.tech> <20220728-rpi-analog-tv-properties-v2-10-459522d653a7@cerno.tech> <242d272b-5b79-986c-9aaf-64e62f6b37ff@gmail.com> <20220905133755.gcmmntg3wnecyqjq@houat> <10ce686a-d7c8-9ce4-3979-735ad8eab3b5@gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="xs3njf2uogpsrjq3" Content-Disposition: inline In-Reply-To: <10ce686a-d7c8-9ce4-3979-735ad8eab3b5@gmail.com> X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Karol Herbst , David Airlie , nouveau@lists.freedesktop.org, dri-devel@lists.freedesktop.org, Phil Elwell , Emma Anholt , Samuel Holland , Jernej Skrabec , Chen-Yu Tsai , Geert Uytterhoeven , Ben Skeggs , linux-sunxi@lists.linux.dev, Thomas Zimmermann , intel-gfx@lists.freedesktop.org, Hans de Goede , Rodrigo Vivi , linux-arm-kernel@lists.infradead.org, Tvrtko Ursulin , Dom Cobley , Dave Stevenson , linux-kernel@vger.kernel.org, Noralf =?utf-8?Q?Tr=C3=B8nnes?= Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" --xs3njf2uogpsrjq3 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Sep 05, 2022 at 06:44:42PM +0200, Mateusz Kwiatkowski wrote: > Hi Maxime, >=20 > W dniu 5.09.2022 o 15:37, Maxime Ripard pisze: > >>> +=A0=A0=A0 vfp =3D vfp_min + (porches_rem / 2); > >>> +=A0=A0=A0 vbp =3D porches - vfp; > >> > >> Relative position of the vertical sync within the VBI effectively move= s the > >> image up and down. Adding that (porches_rem / 2) moves the image up of= f center > >> by that many pixels. I'd keep the VFP always at minimum to keep the im= age > >> centered. > > > > And you would increase the back porch only then? >=20 > Well, increasing vbp only gives a centered image with the default 480i/57= 6i > resolutions. However, only ever changing vbp will cause the image to be a= lways > at the bottom of the screen when the active line count is decreased (e.g. > setting the resolution to 720x480 but for 50Hz "PAL" - like many game con= soles > did back in the day). >=20 > I believe that the perfect solution would: >=20 > - Use the canonical / standard-defined blanking line counts for the stand= ard > =A0 vertical resolutions (480/486/576) > - Increase vfp and vbp from there by the same number if a smaller number = of > =A0 active lines is specified, so that the resulting image is centered > - Likewise, decrease vfp and vbp by the same number if the active line nu= mber > =A0 is larger and there is still leeway (this should allow for seamless h= andling > =A0 of 480i vs. 486i for 60 Hz "NTSC") I'm not sure I understand how that's any different than the code you initially commented on. I would start by taking the entire blanking area, remove the sync period. We only have the two porches now, and I'm starting from the minimum, adding as many pixels in both (unless it's not an even number, in which case the backporch will have the extra pixel). Isn't it the same thing? > - If even more active lines are specified, once the limit for vfp is hit,= then > =A0 decrease vbp only - the resulting image will definitely be off-center= , but > =A0 there's no other way Unless you only want me to consider the front porch maximum? Maxime --xs3njf2uogpsrjq3 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRcEzekXsqa64kGDp7j7w1vZxhRxQUCYxir7QAKCRDj7w1vZxhR xYnUAQDKFDkrZV/fLpjtD+btaCpKvPKkEUm37bnBk3TyD3SBTAD+I0kVAytjVinQ y5KTIrc3dKg0llXX1SWgrvw0OE2vMAI= =QW9g -----END PGP SIGNATURE----- --xs3njf2uogpsrjq3-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 108AFC38145 for ; Wed, 7 Sep 2022 14:34:45 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id DDB2710E78C; Wed, 7 Sep 2022 14:34:34 +0000 (UTC) Received: from new4-smtp.messagingengine.com (new4-smtp.messagingengine.com [66.111.4.230]) by gabe.freedesktop.org (Postfix) with ESMTPS id 05FC110E786; 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Wed, 7 Sep 2022 10:34:24 -0400 (EDT) Date: Wed, 7 Sep 2022 16:34:21 +0200 From: Maxime Ripard To: Mateusz Kwiatkowski Message-ID: <20220907143421.4iopqwhp3yfircsh@houat> References: <20220728-rpi-analog-tv-properties-v2-0-459522d653a7@cerno.tech> <20220728-rpi-analog-tv-properties-v2-10-459522d653a7@cerno.tech> <242d272b-5b79-986c-9aaf-64e62f6b37ff@gmail.com> <20220905133755.gcmmntg3wnecyqjq@houat> <10ce686a-d7c8-9ce4-3979-735ad8eab3b5@gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="xs3njf2uogpsrjq3" Content-Disposition: inline In-Reply-To: <10ce686a-d7c8-9ce4-3979-735ad8eab3b5@gmail.com> Subject: Re: [Intel-gfx] [PATCH v2 10/41] drm/modes: Add a function to generate analog display modes X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Karol Herbst , David Airlie , nouveau@lists.freedesktop.org, dri-devel@lists.freedesktop.org, Phil Elwell , Emma Anholt , Samuel Holland , Jernej Skrabec , Chen-Yu Tsai , Geert Uytterhoeven , Ben Skeggs , linux-sunxi@lists.linux.dev, Thomas Zimmermann , intel-gfx@lists.freedesktop.org, Rodrigo Vivi , Daniel Vetter , linux-arm-kernel@lists.infradead.org, Dom Cobley , Dave Stevenson , linux-kernel@vger.kernel.org, Noralf =?utf-8?Q?Tr=C3=B8nnes?= , Philipp Zabel Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" --xs3njf2uogpsrjq3 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Sep 05, 2022 at 06:44:42PM +0200, Mateusz Kwiatkowski wrote: > Hi Maxime, >=20 > W dniu 5.09.2022 o 15:37, Maxime Ripard pisze: > >>> +=A0=A0=A0 vfp =3D vfp_min + (porches_rem / 2); > >>> +=A0=A0=A0 vbp =3D porches - vfp; > >> > >> Relative position of the vertical sync within the VBI effectively move= s the > >> image up and down. Adding that (porches_rem / 2) moves the image up of= f center > >> by that many pixels. I'd keep the VFP always at minimum to keep the im= age > >> centered. > > > > And you would increase the back porch only then? >=20 > Well, increasing vbp only gives a centered image with the default 480i/57= 6i > resolutions. However, only ever changing vbp will cause the image to be a= lways > at the bottom of the screen when the active line count is decreased (e.g. > setting the resolution to 720x480 but for 50Hz "PAL" - like many game con= soles > did back in the day). >=20 > I believe that the perfect solution would: >=20 > - Use the canonical / standard-defined blanking line counts for the stand= ard > =A0 vertical resolutions (480/486/576) > - Increase vfp and vbp from there by the same number if a smaller number = of > =A0 active lines is specified, so that the resulting image is centered > - Likewise, decrease vfp and vbp by the same number if the active line nu= mber > =A0 is larger and there is still leeway (this should allow for seamless h= andling > =A0 of 480i vs. 486i for 60 Hz "NTSC") I'm not sure I understand how that's any different than the code you initially commented on. I would start by taking the entire blanking area, remove the sync period. We only have the two porches now, and I'm starting from the minimum, adding as many pixels in both (unless it's not an even number, in which case the backporch will have the extra pixel). Isn't it the same thing? > - If even more active lines are specified, once the limit for vfp is hit,= then > =A0 decrease vbp only - the resulting image will definitely be off-center= , but > =A0 there's no other way Unless you only want me to consider the front porch maximum? Maxime --xs3njf2uogpsrjq3 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRcEzekXsqa64kGDp7j7w1vZxhRxQUCYxir7QAKCRDj7w1vZxhR xYnUAQDKFDkrZV/fLpjtD+btaCpKvPKkEUm37bnBk3TyD3SBTAD+I0kVAytjVinQ y5KTIrc3dKg0llXX1SWgrvw0OE2vMAI= =QW9g -----END PGP SIGNATURE----- --xs3njf2uogpsrjq3-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 085A4C54EE9 for ; Wed, 7 Sep 2022 14:38:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: List-Subscribe:List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: In-Reply-To:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Reply-To:Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date :Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; 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Wed, 7 Sep 2022 10:34:24 -0400 (EDT) Date: Wed, 7 Sep 2022 16:34:21 +0200 From: Maxime Ripard To: Mateusz Kwiatkowski Cc: Ben Skeggs , David Airlie , Chen-Yu Tsai , Thomas Zimmermann , Jani Nikula , Lyude Paul , Philipp Zabel , Maarten Lankhorst , Rodrigo Vivi , Tvrtko Ursulin , Jernej Skrabec , Samuel Holland , Karol Herbst , Noralf =?utf-8?Q?Tr=C3=B8nnes?= , Emma Anholt , Daniel Vetter , Joonas Lahtinen , Hans de Goede , linux-arm-kernel@lists.infradead.org, Phil Elwell , intel-gfx@lists.freedesktop.org, Dave Stevenson , dri-devel@lists.freedesktop.org, Dom Cobley , linux-kernel@vger.kernel.org, nouveau@lists.freedesktop.org, linux-sunxi@lists.linux.dev, Geert Uytterhoeven Subject: Re: [PATCH v2 10/41] drm/modes: Add a function to generate analog display modes Message-ID: <20220907143421.4iopqwhp3yfircsh@houat> References: <20220728-rpi-analog-tv-properties-v2-0-459522d653a7@cerno.tech> <20220728-rpi-analog-tv-properties-v2-10-459522d653a7@cerno.tech> <242d272b-5b79-986c-9aaf-64e62f6b37ff@gmail.com> <20220905133755.gcmmntg3wnecyqjq@houat> <10ce686a-d7c8-9ce4-3979-735ad8eab3b5@gmail.com> MIME-Version: 1.0 In-Reply-To: <10ce686a-d7c8-9ce4-3979-735ad8eab3b5@gmail.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220907_073430_123225_59004A98 X-CRM114-Status: GOOD ( 26.15 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============3291222146452857060==" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org --===============3291222146452857060== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="xs3njf2uogpsrjq3" Content-Disposition: inline --xs3njf2uogpsrjq3 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Sep 05, 2022 at 06:44:42PM +0200, Mateusz Kwiatkowski wrote: > Hi Maxime, >=20 > W dniu 5.09.2022 o 15:37, Maxime Ripard pisze: > >>> +=A0=A0=A0 vfp =3D vfp_min + (porches_rem / 2); > >>> +=A0=A0=A0 vbp =3D porches - vfp; > >> > >> Relative position of the vertical sync within the VBI effectively move= s the > >> image up and down. Adding that (porches_rem / 2) moves the image up of= f center > >> by that many pixels. I'd keep the VFP always at minimum to keep the im= age > >> centered. > > > > And you would increase the back porch only then? >=20 > Well, increasing vbp only gives a centered image with the default 480i/57= 6i > resolutions. However, only ever changing vbp will cause the image to be a= lways > at the bottom of the screen when the active line count is decreased (e.g. > setting the resolution to 720x480 but for 50Hz "PAL" - like many game con= soles > did back in the day). >=20 > I believe that the perfect solution would: >=20 > - Use the canonical / standard-defined blanking line counts for the stand= ard > =A0 vertical resolutions (480/486/576) > - Increase vfp and vbp from there by the same number if a smaller number = of > =A0 active lines is specified, so that the resulting image is centered > - Likewise, decrease vfp and vbp by the same number if the active line nu= mber > =A0 is larger and there is still leeway (this should allow for seamless h= andling > =A0 of 480i vs. 486i for 60 Hz "NTSC") I'm not sure I understand how that's any different than the code you initially commented on. I would start by taking the entire blanking area, remove the sync period. We only have the two porches now, and I'm starting from the minimum, adding as many pixels in both (unless it's not an even number, in which case the backporch will have the extra pixel). Isn't it the same thing? > - If even more active lines are specified, once the limit for vfp is hit,= then > =A0 decrease vbp only - the resulting image will definitely be off-center= , but > =A0 there's no other way Unless you only want me to consider the front porch maximum? Maxime --xs3njf2uogpsrjq3 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRcEzekXsqa64kGDp7j7w1vZxhRxQUCYxir7QAKCRDj7w1vZxhR xYnUAQDKFDkrZV/fLpjtD+btaCpKvPKkEUm37bnBk3TyD3SBTAD+I0kVAytjVinQ y5KTIrc3dKg0llXX1SWgrvw0OE2vMAI= =QW9g -----END PGP SIGNATURE----- --xs3njf2uogpsrjq3-- --===============3291222146452857060== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel --===============3291222146452857060==--