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 930A6CDB465 for ; Mon, 16 Oct 2023 12:19:15 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2948D10E1C5; Mon, 16 Oct 2023 12:19:15 +0000 (UTC) Received: from mail-lf1-x12d.google.com (mail-lf1-x12d.google.com [IPv6:2a00:1450:4864:20::12d]) by gabe.freedesktop.org (Postfix) with ESMTPS id F141E10E1C5; Mon, 16 Oct 2023 12:19:13 +0000 (UTC) Received: by mail-lf1-x12d.google.com with SMTP id 2adb3069b0e04-5079f6efd64so2734623e87.2; Mon, 16 Oct 2023 05:19:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1697458752; x=1698063552; darn=lists.freedesktop.org; h=mime-version:references:in-reply-to:message-id:subject:cc:to:from :date:from:to:cc:subject:date:message-id:reply-to; bh=6EhyDqUQjEdCPm8wLm8OFPGsaItsVSXANH1gNBCUPXs=; b=BuRPzH2f+Ad6zXuI+q/My/wciYlDe4MYL7XjPzhR2FevHnNBMQmj06UE/q+onyclnq yQS/8WdmlGKdnkWmSiqeTI/gJSYuo61L2YjUocvcSDuGgcvTNmC/hErP7hAe+f3qfqcp zurQa7CvaQGrp138ckYVp34F4/murKI/Ab3+kAUFf2ayiaoC8hgNy0N9P8tmH6rXdBKZ V4S5oIbUhldp8z4vsu/Cwqkfbg1Zg/MYjvzAR9Kxb7JrcFZm5GPl1qHqafumzNTNcQWc i09EBH+dlfvtHTh6+L579SpC+XdkT+kThuUMwK47I9MYeGcL6rcNc+Urv3xz83uuRGAt CKzA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697458752; x=1698063552; h=mime-version:references:in-reply-to:message-id:subject:cc:to:from :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=6EhyDqUQjEdCPm8wLm8OFPGsaItsVSXANH1gNBCUPXs=; b=DW/JYkUCWZ/p/bWMzy9ChMnEFlknPRu5F5ArWqMl30fszgte9sZSEWSOmyuYpasnc0 IiSsSade8Z6zD/nrUd8pEg1ICof4z+0gUhR+uTDbu3PT5lsJK0vmp+mrjCWL5MWbCEGx LhMEQj89DKvWYNP8ZgxeChjDwW8FFlRNHWQyMLs3Bc5tzb+aMhYFasOdenQqN4PTQ+qz /rY2ifdzS+Y/ZQD6CChArp2GEvuxNZTZWaUtv7vhVXwUoa/3F52Dro3im3txC/L2I8N4 zf9ou9oEGzS8KtQRie8m8m0v9cpZYLpPCdz54Mn8ZChpj9rPAKa2xZaZNpTn6eQ1ST+B 7sOQ== X-Gm-Message-State: AOJu0YxXgdyQTctBl8J+JtpTrC4R+EqtTAXg5dQI4OptQ1At/c5jPZgP EyGAve+mkpJUOCj3J1BVV1A= X-Google-Smtp-Source: AGHT+IFEsLXStxwkdwRXiQB2HK7VTB81PgSSMx0CUVuOSYNVWvv3i/9WVm8Y1nugkxm6d3lmo6GTdA== X-Received: by 2002:a05:6512:132a:b0:503:2877:67e3 with SMTP id x42-20020a056512132a00b00503287767e3mr32451180lfu.6.1697458751652; Mon, 16 Oct 2023 05:19:11 -0700 (PDT) Received: from eldfell ([194.136.85.206]) by smtp.gmail.com with ESMTPSA id x9-20020a056512078900b00507a0098424sm1175692lfr.109.2023.10.16.05.19.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 16 Oct 2023 05:19:10 -0700 (PDT) Date: Mon, 16 Oct 2023 15:18:56 +0300 From: Pekka Paalanen To: =?UTF-8?B?QW5kcsOp?= Almeida Subject: Re: [PATCH v6 6/6] drm/doc: Define KMS atomic state set Message-ID: <20231016151856.74af9305@eldfell> In-Reply-To: References: <20230815185710.159779-1-andrealmeid@igalia.com> <20230815185710.159779-7-andrealmeid@igalia.com> <1b23576d-1649-ff5c-6273-b54729ea46d8@mailbox.org> X-Mailer: Claws Mail 4.1.1 (GTK 3.24.38; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: multipart/signed; boundary="Sig_/69O8rYFAi5QP/ITj8UsboXe"; protocol="application/pgp-signature"; micalg=pgp-sha256 X-BeenThere: amd-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Discussion list for AMD gfx List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: pierre-eric.pelloux-prayer@amd.com, kernel-dev@igalia.com, 'Marek =?UTF-8?B?T2zFocOhayc=?= , Michel =?UTF-8?B?RMOkbnplcg==?= , Dave Airlie , dri-devel@lists.freedesktop.org, Randy Dunlap , xaver.hugl@gmail.com, Daniel Stone , linux-kernel@vger.kernel.org, Rob Clark , amd-gfx@lists.freedesktop.org, Daniel Vetter , alexander.deucher@amd.com, joshua@froggi.es, wayland-devel@lists.freedesktop.org, hwentlan@amd.com, christian.koenig@amd.com, ville.syrjala@linux.intel.com Errors-To: amd-gfx-bounces@lists.freedesktop.org Sender: "amd-gfx" --Sig_/69O8rYFAi5QP/ITj8UsboXe Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Mon, 16 Oct 2023 12:52:32 +0200 Andr=C3=A9 Almeida wrote: > Hi Michel, >=20 > On 8/17/23 12:37, Michel D=C3=A4nzer wrote: > > On 8/15/23 20:57, Andr=C3=A9 Almeida wrote: =20 > >> From: Pekka Paalanen > >> > >> Specify how the atomic state is maintained between userspace and > >> kernel, plus the special case for async flips. > >> > >> Signed-off-by: Pekka Paalanen > >> Signed-off-by: Andr=C3=A9 Almeida =20 > > [...] > > =20 > >> +An atomic commit with the flag DRM_MODE_PAGE_FLIP_ASYNC is allowed to > >> +effectively change only the FB_ID property on any planes. No-operatio= n changes > >> +are ignored as always. [...] =20 > > During the hackfest in Brno, it was mentioned that a commit which re-se= ts the same FB_ID could actually have an effect with VRR: It could trigger = scanout of the next frame before vertical blank has reached its maximum dur= ation. Some kind of mechanism is required for this in order to allow user s= pace to perform low frame rate compensation. > > =20 > Xaver tested this hypothesis in a flipping the same fb in a VRR monitor=20 > and it worked as expected, so this shouldn't be a concern. Right, so it must have some effect. It cannot be simply ignored like in the proposed doc wording. Do we special-case re-setting the same FB_ID as "not a no-op" or "not ignored" or some other way? Thanks, pq --Sig_/69O8rYFAi5QP/ITj8UsboXe Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEJQjwWQChkWOYOIONI1/ltBGqqqcFAmUtKjAACgkQI1/ltBGq qqf20RAAnw0oZXemzgfErYkfbspei2AiW5NBarJedqPGc6nsl6TnUV3oNRGogGLL vJpsyTvfxmYgb79fTvuB5fc0nJJecuwtQ17W6x9VcwJkZOpdRi2Uez2AO9dvNpSW VKVVuyujVmyCk+UofjyHa+zUJC31YakmhiF6LFPB0IyYdo/+o6svRpn2lmHNXRU/ v4KFGi8S1wsg3iokMemnpJZYvdc+mSH0W9WJ0kaesv3Wn05xnBpmfySR9DZzUq9t qUoGipgOnfQ/LLfkvLqece8bxP6ENtFNERXfE6YpWz0LTIqsW+TCV/QfmcgrD6iU 2R/+LH8GzZ2pjovxbqXsps5QKTB+wkSydkDQuwt0eR4Rx7k1NAzaKWP2Xg934wDB BIOzsHzjB8dchzjf3+8/ezSuocAxWtGRV6eaJ8sFLYFh6OB+bi6K00v7eg4J5scK aSjf5fmeP2JNWbfEqLlK1tWYAsT37g08MUEIewGXBceG3C3vaNgwLjgKFbL/KNff uLL0zgusaKtDxxKsDCti6bVJb+ntmpnp92PGh2lPp33DplZ32/5/kd7fwe9Sh21K iPFaqtyBR4u1BadTVhekLmXNY0YIpevjdNl+B+EBRvM6HaxHRdrnakLgg6IWDEsY 8oEZ3kIQ1cJxtNVktLqy6X8T9fZL4U7emXJKvYdJMiubbMq5MFs= =ZKmt -----END PGP SIGNATURE----- --Sig_/69O8rYFAi5QP/ITj8UsboXe-- 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 7C90ECDB482 for ; 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Mon, 16 Oct 2023 05:19:10 -0700 (PDT) Date: Mon, 16 Oct 2023 15:18:56 +0300 From: Pekka Paalanen To: =?UTF-8?B?QW5kcsOp?= Almeida Subject: Re: [PATCH v6 6/6] drm/doc: Define KMS atomic state set Message-ID: <20231016151856.74af9305@eldfell> In-Reply-To: References: <20230815185710.159779-1-andrealmeid@igalia.com> <20230815185710.159779-7-andrealmeid@igalia.com> <1b23576d-1649-ff5c-6273-b54729ea46d8@mailbox.org> X-Mailer: Claws Mail 4.1.1 (GTK 3.24.38; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: multipart/signed; boundary="Sig_/69O8rYFAi5QP/ITj8UsboXe"; protocol="application/pgp-signature"; micalg=pgp-sha256 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: pierre-eric.pelloux-prayer@amd.com, kernel-dev@igalia.com, 'Marek =?UTF-8?B?T2zFocOhayc=?= , Michel =?UTF-8?B?RMOkbnplcg==?= , dri-devel@lists.freedesktop.org, Randy Dunlap , xaver.hugl@gmail.com, linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org, alexander.deucher@amd.com, joshua@froggi.es, wayland-devel@lists.freedesktop.org, hwentlan@amd.com, christian.koenig@amd.com Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" --Sig_/69O8rYFAi5QP/ITj8UsboXe Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Mon, 16 Oct 2023 12:52:32 +0200 Andr=C3=A9 Almeida wrote: > Hi Michel, >=20 > On 8/17/23 12:37, Michel D=C3=A4nzer wrote: > > On 8/15/23 20:57, Andr=C3=A9 Almeida wrote: =20 > >> From: Pekka Paalanen > >> > >> Specify how the atomic state is maintained between userspace and > >> kernel, plus the special case for async flips. > >> > >> Signed-off-by: Pekka Paalanen > >> Signed-off-by: Andr=C3=A9 Almeida =20 > > [...] > > =20 > >> +An atomic commit with the flag DRM_MODE_PAGE_FLIP_ASYNC is allowed to > >> +effectively change only the FB_ID property on any planes. No-operatio= n changes > >> +are ignored as always. [...] =20 > > During the hackfest in Brno, it was mentioned that a commit which re-se= ts the same FB_ID could actually have an effect with VRR: It could trigger = scanout of the next frame before vertical blank has reached its maximum dur= ation. Some kind of mechanism is required for this in order to allow user s= pace to perform low frame rate compensation. > > =20 > Xaver tested this hypothesis in a flipping the same fb in a VRR monitor=20 > and it worked as expected, so this shouldn't be a concern. Right, so it must have some effect. It cannot be simply ignored like in the proposed doc wording. Do we special-case re-setting the same FB_ID as "not a no-op" or "not ignored" or some other way? Thanks, pq --Sig_/69O8rYFAi5QP/ITj8UsboXe Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEJQjwWQChkWOYOIONI1/ltBGqqqcFAmUtKjAACgkQI1/ltBGq qqf20RAAnw0oZXemzgfErYkfbspei2AiW5NBarJedqPGc6nsl6TnUV3oNRGogGLL vJpsyTvfxmYgb79fTvuB5fc0nJJecuwtQ17W6x9VcwJkZOpdRi2Uez2AO9dvNpSW VKVVuyujVmyCk+UofjyHa+zUJC31YakmhiF6LFPB0IyYdo/+o6svRpn2lmHNXRU/ v4KFGi8S1wsg3iokMemnpJZYvdc+mSH0W9WJ0kaesv3Wn05xnBpmfySR9DZzUq9t qUoGipgOnfQ/LLfkvLqece8bxP6ENtFNERXfE6YpWz0LTIqsW+TCV/QfmcgrD6iU 2R/+LH8GzZ2pjovxbqXsps5QKTB+wkSydkDQuwt0eR4Rx7k1NAzaKWP2Xg934wDB BIOzsHzjB8dchzjf3+8/ezSuocAxWtGRV6eaJ8sFLYFh6OB+bi6K00v7eg4J5scK aSjf5fmeP2JNWbfEqLlK1tWYAsT37g08MUEIewGXBceG3C3vaNgwLjgKFbL/KNff uLL0zgusaKtDxxKsDCti6bVJb+ntmpnp92PGh2lPp33DplZ32/5/kd7fwe9Sh21K iPFaqtyBR4u1BadTVhekLmXNY0YIpevjdNl+B+EBRvM6HaxHRdrnakLgg6IWDEsY 8oEZ3kIQ1cJxtNVktLqy6X8T9fZL4U7emXJKvYdJMiubbMq5MFs= =ZKmt -----END PGP SIGNATURE----- --Sig_/69O8rYFAi5QP/ITj8UsboXe-- 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5F9AFCDB474 for ; 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Mon, 16 Oct 2023 05:19:11 -0700 (PDT) Received: from eldfell ([194.136.85.206]) by smtp.gmail.com with ESMTPSA id x9-20020a056512078900b00507a0098424sm1175692lfr.109.2023.10.16.05.19.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 16 Oct 2023 05:19:10 -0700 (PDT) Date: Mon, 16 Oct 2023 15:18:56 +0300 From: Pekka Paalanen To: =?UTF-8?B?QW5kcsOp?= Almeida Cc: Michel =?UTF-8?B?RMOkbnplcg==?= , xaver.hugl@gmail.com, pierre-eric.pelloux-prayer@amd.com, Daniel Vetter , 'Marek =?UTF-8?B?T2zFocOhayc=?= , Randy Dunlap , Daniel Stone , linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, hwentlan@amd.com, Rob Clark , ville.syrjala@linux.intel.com, kernel-dev@igalia.com, alexander.deucher@amd.com, Dave Airlie , christian.koenig@amd.com, joshua@froggi.es, wayland-devel@lists.freedesktop.org Subject: Re: [PATCH v6 6/6] drm/doc: Define KMS atomic state set Message-ID: <20231016151856.74af9305@eldfell> In-Reply-To: References: <20230815185710.159779-1-andrealmeid@igalia.com> <20230815185710.159779-7-andrealmeid@igalia.com> <1b23576d-1649-ff5c-6273-b54729ea46d8@mailbox.org> X-Mailer: Claws Mail 4.1.1 (GTK 3.24.38; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: multipart/signed; boundary="Sig_/69O8rYFAi5QP/ITj8UsboXe"; protocol="application/pgp-signature"; micalg=pgp-sha256 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --Sig_/69O8rYFAi5QP/ITj8UsboXe Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Mon, 16 Oct 2023 12:52:32 +0200 Andr=C3=A9 Almeida wrote: > Hi Michel, >=20 > On 8/17/23 12:37, Michel D=C3=A4nzer wrote: > > On 8/15/23 20:57, Andr=C3=A9 Almeida wrote: =20 > >> From: Pekka Paalanen > >> > >> Specify how the atomic state is maintained between userspace and > >> kernel, plus the special case for async flips. > >> > >> Signed-off-by: Pekka Paalanen > >> Signed-off-by: Andr=C3=A9 Almeida =20 > > [...] > > =20 > >> +An atomic commit with the flag DRM_MODE_PAGE_FLIP_ASYNC is allowed to > >> +effectively change only the FB_ID property on any planes. No-operatio= n changes > >> +are ignored as always. [...] =20 > > During the hackfest in Brno, it was mentioned that a commit which re-se= ts the same FB_ID could actually have an effect with VRR: It could trigger = scanout of the next frame before vertical blank has reached its maximum dur= ation. Some kind of mechanism is required for this in order to allow user s= pace to perform low frame rate compensation. > > =20 > Xaver tested this hypothesis in a flipping the same fb in a VRR monitor=20 > and it worked as expected, so this shouldn't be a concern. Right, so it must have some effect. It cannot be simply ignored like in the proposed doc wording. Do we special-case re-setting the same FB_ID as "not a no-op" or "not ignored" or some other way? 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