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 453F8CA1005 for ; Tue, 2 Sep 2025 12:30:50 +0000 (UTC) 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:MIME-Version:Message-ID:Date:References:In-Reply-To:Subject:Cc: To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=GNCNaMiPJDXvB/7iEX4grRokMrqO0VUFGnAoYlmBZNk=; b=xp1hP/HOMgfiMYdZsNCNc8VoAH NG39uH1lZObCh7aLvwCIpp/a9xmzAYxJmDJyZ/iBDq1Hlh/bPYSdI9Hv3SVnFZH1jbDK4cGA8uybA bbAdPrL/pBPBQxJzoB4oyj/xnIRevIBsLyyj4jrYLT8t3EzJVBYaQWM1Z0dLkOw7JHJmg1Hc7/3WD f4xAbHUGVdMO3JYSaJS7n5YE3vqYRnAGnOW5nBKfbqFh78E8yn9TIha78trGXpKhyDtJikiJoNEgp XsupFTJyuIrp+c5Vd+cG/y3oQMCVLN4OQRYStCuepN5suFhAhIy2inMQmpYQL+CJwGFlFYmZpS1Xx FuFMzbvg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1utQ9r-0000000HI1E-0ARb; Tue, 02 Sep 2025 12:30:43 +0000 Received: from [195.187.100.5] (helo=ni.piap.pl) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1utNil-0000000GVYY-048k; Tue, 02 Sep 2025 09:54:40 +0000 Received: from t19.piap.pl (OSB1819.piap.pl [10.0.9.19]) by ni.piap.pl (Postfix) with ESMTPS id 16763C3EEACD; Tue, 2 Sep 2025 11:54:28 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 ni.piap.pl 16763C3EEACD From: =?utf-8?Q?Krzysztof_Ha=C5=82asa?= To: Adam Ford Cc: Stefan Klug , Laurent Pinchart , Dafna Hirschfeld , Heiko Stuebner , Paul Elder , Jacopo Mondi , Ondrej Jirman , linux-media@vger.kernel.org, linux-rockchip@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: FYI: i.MX8MP ISP (RKISP1) MI registers corruption: resolved In-Reply-To: (Adam Ford's message of "Tue, 12 Aug 2025 13:22:54 -0500") References: <175308758352.3134829.9472501038683860006@localhost> <175326599663.2811177.16620980968274114885@localhost> <175344176070.2811177.10693943493658922992@localhost> <20250812103243.GK30054@pendragon.ideasonboard.com> <175501095338.74722.11604545949710100799@localhost> Date: Tue, 02 Sep 2025 11:54:27 +0200 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250902_025435_291490_900C423C X-CRM114-Status: UNSURE ( 8.33 ) X-CRM114-Notice: Please train this message. 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi, summary: I've done a few additional tests and it seems the MEDIA_AXI clock is the problem. Reducing it to 400 MHz while still running MEDIA_ISP at 500 MHz produces no errors. MEDIA_ISP at 400 MHz and MEDIA_AXI at 500 MHz produces errors, though (register address errors while reading and writing from/to ISP MI (memory interface) registers, only on the secondary ISP (isp1), and generally only while streaming data from the ISP). What is driven by MEDIA_AXI clock root? MEDIAMIX: ISI, LCDIF, ISP, DWE. According to both datasheets (industrial and commercial), MEDIA_AXI is limited to 400 MHz in normal mode and 500 MHz in overdrive mode. All my hardware is setup for overdrive mode, though (two manufacturers, both using the same PMIC setup). Since no hardware in the official Linux kernel tree (DT) uses the second ISP... Should we just add a warning to the imx8mp.dtsi and be done with it? Out of tree hardware using isp1 (csi1) obviously exists. --=20 Krzysztof "Chris" Ha=C5=82asa Sie=C4=87 Badawcza =C5=81ukasiewicz Przemys=C5=82owy Instytut Automatyki i Pomiar=C3=B3w PIAP Al. Jerozolimskie 202, 02-486 Warszawa