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 EDF4EC77B7A for ; Fri, 26 May 2023 12:52:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236495AbjEZMw0 (ORCPT ); Fri, 26 May 2023 08:52:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41956 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230421AbjEZMwZ (ORCPT ); Fri, 26 May 2023 08:52:25 -0400 Received: from mx1.tq-group.com (mx1.tq-group.com [93.104.207.81]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 62E0B114 for ; Fri, 26 May 2023 05:52:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tq-group.com; i=@tq-group.com; q=dns/txt; s=key1; t=1685105543; x=1716641543; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=P56jRYx8x4wiLyblEJCYsDvHn8dkjs3K/b4UWx2IjD8=; b=m5rJiYviUmmf6KuHWee9TkbZ3/LYrIYI6jyCUUIqWpqYipeaYJXCNhSh Pwk/BIXnecml2bX2/9zhkAk9D/7WFCXZwml0lFzQZjmHTwgYGJlkYE6oS I6ZP8/w85QxGXNpkEwzm4oa369VdtFD2IMGvc/QnJoYJlJSDQfqH0G6WF MyRYm8LH48uThtVslq1rhnNyVHv6Mdbgvng9X3aD6LkK6iB0B0ca2BjwY V4h4gdRQUThfi+HHwgSWfe9+RFujG8KIHgMiQmWW+BAN8433sfuEy5wuo CJXGxhIsw9Y/Gb6AX7bB4mb6AsI96TMkPQWjc04OUaXwuhUrn6EtMfokc Q==; X-IronPort-AV: E=Sophos;i="6.00,194,1681164000"; d="scan'208";a="31128837" Received: from unknown (HELO tq-pgp-pr1.tq-net.de) ([192.168.6.15]) by mx1-pgp.tq-group.com with ESMTP; 26 May 2023 14:52:21 +0200 Received: from mx1.tq-group.com ([192.168.6.7]) by tq-pgp-pr1.tq-net.de (PGP Universal service); Fri, 26 May 2023 14:52:21 +0200 X-PGP-Universal: processed; by tq-pgp-pr1.tq-net.de on Fri, 26 May 2023 14:52:21 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tq-group.com; i=@tq-group.com; q=dns/txt; s=key1; t=1685105541; x=1716641541; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=P56jRYx8x4wiLyblEJCYsDvHn8dkjs3K/b4UWx2IjD8=; b=XtHxJgaFzNgqe1Zu1AOsjHGfuE9A/6NgT7djD9nkyi6A/p2UW+vftRxa YNRyuB0L3CeqCOJUn2P2JTc9qAjURkzfP/VvqZrd0ZdYXoPM4jWYPDCdv yvpR2mlrZg1OZe5DRIVLbVWopBJE++DXpiDNHTI7ZIhFCvV9oTPPqea5/ zrzuTa8Q+UQ9ltnY1wd8RuibKb6ycOyqMtxqPmuhOJnOONNr+Ejan8pN8 ftTatV16rGYHkXVLfBA9sXEfxZfVzVGABmmAYuaMk9OnWCq1Y8Y0XURD2 /zUIegsFxdWTsccLF2ixZhwg1NoKej8iQa6CxEWbnTRc5mkz2rWFRsP/G Q==; X-IronPort-AV: E=Sophos;i="6.00,194,1681164000"; d="scan'208";a="31128836" Received: from vtuxmail01.tq-net.de ([10.115.0.20]) by mx1.tq-group.com with ESMTP; 26 May 2023 14:52:21 +0200 Received: from steina-w.localnet (unknown [10.123.53.21]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by vtuxmail01.tq-net.de (Postfix) with ESMTPSA id 64188280082; Fri, 26 May 2023 14:52:21 +0200 (CEST) From: Alexander Stein To: Marek Vasut Cc: linux-arm-kernel@lists.infradead.org, Conor Dooley , Fabio Estevam , Krzysztof Kozlowski , NXP Linux Team , Pengutronix Kernel Team , Rob Herring , Sascha Hauer , Shawn Guo , devicetree@vger.kernel.org Subject: Re: [PATCH] arm64: dts: imx8mp: Add TC9595 bridge on DH electronics i.MX8M Plus DHCOM Date: Fri, 26 May 2023 14:52:21 +0200 Message-ID: <7530294.EvYhyI6sBW@steina-w> Organization: TQ-Systems GmbH In-Reply-To: <75c45018-fae3-aa9d-db5d-7d378f69b53c@denx.de> References: <20230515162424.67597-1-marex@denx.de> <1953702.usQuhbGJ8B@steina-w> <75c45018-fae3-aa9d-db5d-7d378f69b53c@denx.de> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="iso-8859-1" Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hi Marek, Am Mittwoch, 24. Mai 2023, 12:37:50 CEST schrieb Marek Vasut: > On 5/24/23 12:24, Alexander Stein wrote: >=20 > Hi, >=20 > >>> Looking at the AUX_CH+/- signals, I can see the native aux request and > >>> the > >>> (presumable) correct answer (DP_DPCD_REV register) from the display. = But > >>> for some reason the bridge runs into a aux timeout. > >>> I can see in the DP0_AUXSTATUS register the bus gets busy (0x1) after > >>> starting transfer. But after the tc_aux_wait_busy() call DP0_AUXSTATUS > >>> his indicating a timeout and sync error (0x310002). > >>> When changing the "Aux Bit Period Calculator Threshold" to 5 (register > >>> AUXCFG1), the sync error is gone, but the timeout still happens. > >>>=20 > >>> The frequency used from the display is ~1MHz, which should be okay. So > >>> on > >>> the electrical side all seems okay, but the native aux transfer don't > >>> work. > >>=20 > >> I recall DPCD read timeouts, but those were usually triggered by either > >> bad clock or wiring problems (the devkit wiring I used was horrible at > >> the beginning) from what I can recall. > >=20 > > bad clock in the sense of badly configured or bad xtal hardware? >=20 > As in, the xtal clock drives the internal PLLs and if those are > misconfigured for whatever reason, the chip can misbehave. You might > want to double-check the clock routing chapter in the toshiba bridge > datasheet and matching registers. >=20 > Have you tried forcing the chip into 1.62G (instead of 2.7G) operation > and into 1-lane DP instead of 2-lane DP mode ? Does that make any > difference ? The initial AUX problem is unrelated to DP link. I had problems way before= =20 2.7G or 2-lane DP comes into play. The problem in aux channel was caused by= =20 bad clock input :( and the DSI host not putting all DSI lines into LP-11. =46or some reason apparently nobody had to do these kind of changes on=20 samsung_dsim. I had to enable all DSI lines (incl. clock) on dsim for the=20 bridge to properly use the AUX channel. With that fixed, DPCD read is successfull and DP link training seems okay, = as=20 I can enable the test pattern on the bridge. But displaying regular DSI stream is not working. I see the DSI error count= er=20 continuously increasing in the DSIERRCNT register (0x300). =46orcing 1-lane DP or 1.62G operation reduces the possible resolution but= =20 displaying does still not work. Best regards Alexander =2D-=20 TQ-Systems GmbH | M=FChlstra=DFe 2, Gut Delling | 82229 Seefeld, Germany Amtsgericht M=FCnchen, HRB 105018 Gesch=E4ftsf=FChrer: Detlef Schneider, R=FCdiger Stahl, Stefan Schneider http://www.tq-group.com/