From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=185.70.43.100 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794293493; b=bYi6wWHo+dtgVCYCxvwLvtEjjIHpoBmNR0FTiC2gjIfJNIXlhAF0B8P8+yxFQbaadTli O3QI2eufUxLKC4AHiRPDpREa9UoofCAqIw/oS1xI5LMoCgkcSLeR1e8lGB982vxZLZKpL g5RbEMrtlVmrdtAzFZYExz+qKjyl+muYyMK2gTgm2sJQtmhN07FEUbI7m1XPBNt7c9jrE 9F2iEoJCCvitW5y/l881EKXgGUQjj6nfa9O+15xsrAUU7QywlX4fNh8aCfLdrYm3/IAUP ec6xtO6pqqOyglPowBKnS67IWVKwT2RV4usFAUrVgXUw6x3KiVoH+kE22FYcAvP4uCw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794293493; h=DMARC-Filter:DKIM-Signature:Date:To:From:Cc:Subject:Message-ID: In-Reply-To:References:Feedback-ID:X-Pm-Message-ID:MIME-Version: Content-Type:Content-Transfer-Encoding; bh=AQk2bWnn9qEiJB55CfKKDZX/EDk/uqfS9SOxZvrUyFI=; b=RGbRRm7XjA2rOpIpIwpS70DfFvridrVsM4Occe8rA+tZX4lGEdtn55BXSO5BGHGV5YbG /FnlGvqniOw+elNOk4UdhcN7F/j3Q+YZ5X2Sn4Jz0fuDwF0uqxw0m5t4vuxHoUhBGi+sl lcf1zsjRJ+z02fEkuOW3/MwtZpvBdPh8L+bSF9iSlPqsQIN+6xlHoU8h6OHkwKna46+Vf M0HnZnbE/ozudVUAkT1TednMNQkWOrzZ0gMThocLzWnfvgXR+ZYkoW7GKQ9+48vYX2AvF yjZl4Y6HXfirqlcy4JfWta7hoYVqgaFe3xQFhZWVYoliyeVX09FWnDKN9NfPoLgxN5g== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=pm.me; spf=pass smtp.mailfrom=pm.me; dkim=pass header.d=pm.me header.i=@pm.me header.a=rsa-sha256 header.s=protonmail3 header.b=nvcJZWW5; arc=none smtp.remote-ip=185.70.43.100 Received: from mail-43100.protonmail.ch (mail-43100.protonmail.ch [185.70.43.100]) (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 326A0606A31C for ; Tue, 10 Nov 2026 06:51:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 326A0606A31C 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, unprotected) header.d=pm.me header.i=@pm.me header.a=rsa-sha256 header.s=protonmail3 header.b=nvcJZWW5 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pm.me; s=protonmail3; t=1794293489; x=1794552689; bh=AQk2bWnn9qEiJB55CfKKDZX/EDk/uqfS9SOxZvrUyFI=; 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=nvcJZWW5UYLD+L8c0CIhmpOFLYBxA/XgI2e3MQNTIZ9dezhvbModSbSWDbNG6NMru tz94klciV1ccErUrZgATbxtZlFW27+oiTkJ732ruO5TvcMhGC5AeOCGEI02FrIMH5i FLYVU4tK+LY6wmYpp7V5/6aMaNIFqcHNkoo/z5kzEbDwHLDmy6zbHXwO+CFXdSGNzV N075A9DOC6CW+WgzUU+/+TchZoRylwTVTFGsothmWm4tpu/pUGzLiXl4E1/21eTJWN dalYu7erMAR4WGWkLZSl6WUQYN7FsKy/HgB3QHjaTRPy611vZZbueiOiigwq6k0fOA IA1YK/QvGJX4Q== Date: Tue, 10 Nov 2026 06:51:25 +0000 To: Manik Bajpai , Divyamani Tripathi From: Sergey Lebedev Cc: Sakari Ailus , Bingbu Cao , Antti Laakso , German Pablo Lindo , Christian Murphy , Hans Verkuil , Mauro Carvalho Chehab , Greg Kroah-Hartman , linux-media@vger.kernel.org, linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH] media: staging/ipu7: snoop ISYS writes to capture buffers Message-ID: <20261110065119.20575-1-lsa.uz@pm.me> In-Reply-To: References: <20261007183311.24637-1-lsa.uz@pm.me> Feedback-ID: 113843758:user:proton X-Pm-Message-ID: 90cce48b7b9b0d962718d9c5e3831106eccc5c1f X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Hi Manik, Divyamani, Sakari added you to this patch in October. Is is_snoop =3D 1 on the capture pin right for IPU7, and for IPU 7.5, which I could not test? Christian Murphy sent a different fix for the same rows in August, which I missed: a clflush of each capture buffer in buf_prepare and buf_finish, with is_snoop left at 0. If the snoop bit cannot be relied on, his is the one to take: https://lore.kernel.org/all/20260824224139.21256-1-christian@themurphys.eu/ With is_snoop =3D 1, frames holding rows of the buffer's previous fill went from 301 of 698 and 684 of 697 to none, reading every frame with the CPU, and 4224x3136 raw at about 790 MB/s still ran at 29.95 fps. The patch applies to v7.4-rc1 unchanged. It carries an Assisted-by tag, which 7.4-rc1 no longer accepts; Sakari, please drop it when applying, or I will resend without it. Sergey