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 X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_NEOMUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B5BA2C282D8 for ; Fri, 1 Feb 2019 13:12:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8E849218AF for ; Fri, 1 Feb 2019 13:12:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729746AbfBANMV (ORCPT ); Fri, 1 Feb 2019 08:12:21 -0500 Received: from relay4-d.mail.gandi.net ([217.70.183.196]:54363 "EHLO relay4-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726450AbfBANMV (ORCPT ); Fri, 1 Feb 2019 08:12:21 -0500 X-Originating-IP: 90.88.147.226 Received: from localhost (aaubervilliers-681-1-27-226.w90-88.abo.wanadoo.fr [90.88.147.226]) (Authenticated sender: maxime.ripard@bootlin.com) by relay4-d.mail.gandi.net (Postfix) with ESMTPSA id 87834E0007; Fri, 1 Feb 2019 13:12:18 +0000 (UTC) Date: Fri, 1 Feb 2019 14:12:18 +0100 From: Maxime Ripard To: Paul Kocialkowski Cc: dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-sunxi@googlegroups.com, David Airlie , Chen-Yu Tsai Subject: Re: [PATCH] drm/sun4i: tcon: Prepare and enable TCON channel 0 clock at init Message-ID: <20190201131218.633gv3npsekliezj@flea> References: <20190131132550.26355-1-paul.kocialkowski@bootlin.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="mw7tj6i6edxi3mtm" Content-Disposition: inline In-Reply-To: <20190131132550.26355-1-paul.kocialkowski@bootlin.com> User-Agent: NeoMutt/20180716 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --mw7tj6i6edxi3mtm Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Jan 31, 2019 at 02:25:50PM +0100, Paul Kocialkowski wrote: > When initializing clocks, a reference to the TCON channel 0 clock is > obtained. However, the clock is never prepared and enabled later. > Switching from simplefb to DRM actually disables the clock (that was > usually configured by U-Boot) because of that. >=20 > On the V3s, this results in a hang when writing to some mixer registers > when switching over to DRM from simplefb. >=20 > Fix this by preparing and enabling the clock when initializing other > clocks. Waiting for sun4i_tcon_channel_enable to enable the clock is > apparently too late and results in the same mixer register access hang. >=20 > Signed-off-by: Paul Kocialkowski Applied, thanks! Maxime --=20 Maxime Ripard, Bootlin Embedded Linux and Kernel engineering https://bootlin.com --mw7tj6i6edxi3mtm Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQRcEzekXsqa64kGDp7j7w1vZxhRxQUCXFRFsgAKCRDj7w1vZxhR xWwCAP9nOM5TEB8sq5A3dUGCZ7iQqjy0qQCGIFOMG2kI5sFgNgD8D0dRKAXCf1j5 TIxNDj5ErrqgTSJqEagzyWos9NDO5QA= =PWKT -----END PGP SIGNATURE----- --mw7tj6i6edxi3mtm--