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 955C9C433EF for ; Mon, 11 Apr 2022 07:54:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237098AbiDKH4Z (ORCPT ); Mon, 11 Apr 2022 03:56:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45170 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230254AbiDKH4Y (ORCPT ); Mon, 11 Apr 2022 03:56:24 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EDE6ABC09 for ; Mon, 11 Apr 2022 00:54:10 -0700 (PDT) Received: from ptx.hi.pengutronix.de ([2001:67c:670:100:1d::c0]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1ndos4-00080i-BK; Mon, 11 Apr 2022 09:54:00 +0200 Received: from sha by ptx.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1ndos1-0007qZ-Jk; Mon, 11 Apr 2022 09:53:57 +0200 Date: Mon, 11 Apr 2022 09:53:57 +0200 From: Sascha Hauer To: Alex Bee Cc: dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, devicetree@vger.kernel.org, kernel@pengutronix.de, Andy Yan , Benjamin Gaignard , Michael Riesch , Sandy Huang , Heiko =?iso-8859-15?Q?St=FCbner?= , Peter Geis Subject: Re: [PATCH v10 12/24] drm/rockchip: dw_hdmi: drop mode_valid hook Message-ID: <20220411075357.GQ4012@pengutronix.de> References: <20220408112238.1274817-1-s.hauer@pengutronix.de> <20220408112238.1274817-13-s.hauer@pengutronix.de> <8fac5d72-c635-521c-e7d1-a3980a4ed719@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8fac5d72-c635-521c-e7d1-a3980a4ed719@gmail.com> X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-IRC: #ptxdist @freenode X-Accept-Language: de,en X-Accept-Content-Type: text/plain X-Uptime: 09:14:52 up 11 days, 19:44, 70 users, load average: 0.07, 0.26, 0.26 User-Agent: Mutt/1.10.1 (2018-07-13) X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c0 X-SA-Exim-Mail-From: sha@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: devicetree@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Sun, Apr 10, 2022 at 01:31:23PM +0200, Alex Bee wrote: > Am 08.04.22 um 13:22 schrieb Sascha Hauer: > > The driver checks if the pixel clock of the given mode matches an entry > > in the mpll config table. The frequencies in the mpll table are meant as > > a frequency range up to which the entry works, not as a frequency that > > must match the pixel clock. The downstream Kernel also does not have > > this check, so drop it to allow for more display resolutions. > > > > Signed-off-by: Sascha Hauer > > --- > > > You're correct: That frequency is meant to be greater or equal. But I'm > not sure if it makes sense to completely drop it - what happens for > clocks rates > 600 MHz which might be supported by later generation > sinks (HDMI 2.1 or later)? > As these are not supported by the IPs/PHYs currently supported by that > driver a reason a simple > > int i; > > > > for (i = 0; mpll_cfg[i].mpixelclock != (~0UL); i++) { > > - if (pclk == mpll_cfg[i].mpixelclock) { > > + if (pclk >= mpll_cfg[i].mpixelclock) { Should be <= No other user currently in the tree has this check. hdmi_phy_configure_dwc_hdmi_3d_tx() has this: > /* PLL/MPLL Cfg - always match on final entry */ > for (; mpll_config->mpixelclock != ~0UL; mpll_config++) > if (mpixelclock <= mpll_config->mpixelclock) > break; > > for (; curr_ctrl->mpixelclock != ~0UL; curr_ctrl++) > if (mpixelclock <= curr_ctrl->mpixelclock) > break; > > for (; phy_config->mpixelclock != ~0UL; phy_config++) > if (mpixelclock <= phy_config->mpixelclock) > break; > > if (mpll_config->mpixelclock == ~0UL || > curr_ctrl->mpixelclock == ~0UL || > phy_config->mpixelclock == ~0UL) > return -EINVAL; This means we already have this check and others already in the generic part of the dw-hdmi driver. Should we maybe do the above in dw_hdmi_bridge_mode_valid() instead of doing it in the users? Sascha -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |