Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752840AbdI3L6Q (ORCPT ); Sat, 30 Sep 2017 07:58:16 -0400 Received: from mail-pf0-f193.google.com ([209.85.192.193]:37646 "EHLO mail-pf0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752157AbdI3L6M (ORCPT ); Sat, 30 Sep 2017 07:58:12 -0400 X-Google-Smtp-Source: AOwi7QCyAVsawnbxUbPN/oK62WWAu6y/dHhN38+lPAqTq+4JjZigcBNlZ2KKYFo2HAV/q6ZmAbNLmw== Subject: Re: [RESEND RFC PATCH 0/7] sun8i H3 HDMI glue driver for DW HDMI To: Jernej Skrabec , maxime.ripard@free-electrons.com, wens@csie.org Cc: Laurent.pinchart@ideasonboard.com, hans.verkuil@cisco.com, narmstrong@baylibre.com, dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org, icenowy@aosc.io, linux-sunxi@googlegroups.com, linux-media@vger.kernel.org References: <20170920200124.20457-1-jernej.skrabec@siol.net> From: Alexey Kardashevskiy Message-ID: <51c50157-6794-852b-f89d-647b9cf06ef2@ozlabs.ru> Date: Sat, 30 Sep 2017 21:58:03 +1000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <20170920200124.20457-1-jernej.skrabec@siol.net> Content-Type: text/plain; charset=utf-8 Content-Language: en-AU Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4450 Lines: 105 On 21/09/17 06:01, Jernej Skrabec wrote: > [added media mailing list due to CEC question] > > This patch series adds a HDMI glue driver for Allwinner H3 SoC. For now, only > video and CEC functionality is supported. Audio needs more tweaks. > > Series is based on the H3 DE2 patch series available on mailing list: > http://lists.infradead.org/pipermail/linux-arm-kernel/2017-August/522697.html > (ignore patches marked with [NOT FOR REVIEW NOW] tag) > > Patch 1 adds support for polling plug detection since custom PHY used here > doesn't support HPD interrupt. > > Patch 2 enables overflow workaround for v1.32a. This HDMI controller exhibits > same issues as HDMI controller used in iMX6 SoCs. > > Patch 3 adds CLK_SET_RATE_PARENT to hdmi clock. > > Patch 4 adds dt bindings documentation. > > Patch 5 adds actual H3 HDMI glue driver. > > Patch 6 and 7 add HDMI node to DT and enable it where needed. > > Allwinner used DW HDMI controller in a non standard way: > - register offsets obfuscation layer, which can fortunately be turned off > - register read lock, which has to be disabled by magic number > - custom PHY, which have to be initialized before DW HDMI controller > - non standard clocks > - no HPD interrupt > > Because of that, I have two questions: > - Since HPD have to be polled, is it enough just to enable poll mode? I'm > mainly concerned about invalidating CEC address here. > - PHY has to be initialized before DW HDMI controller to disable offset > obfuscation and read lock among other things. This means that all clocks have > to be enabled in glue driver. This poses a problem, since when using > component model, dw-hdmi bridge uses drvdata for it's own private data and > prevents glue layer to pass a pointer to unbind function, where clocks should > be disabled. I noticed same issue in meson DW HDMI glue driver, where clocks > are also not disabled when unbind callback is called. I noticed that when H3 > SoC is shutdown, HDMI output is still enabled and lastest image is shown on > monitor until it is unplugged from power supply. Is there any simple solution > to this? > > Chen-Yu, > TL Lim was unable to obtain any answer from Allwinner about HDMI clocks. I think > it is safe to assume that divider in HDMI clock doesn't have any effect. > > Branch based on linux-next from 1. September with integrated patches is > available here: > https://github.com/jernejsk/linux-1/tree/h3_hdmi_rfc Out of curiosity I tried this one and got: [ 0.071711] sun4i-usb-phy 1c19400.phy: Couldn't request ID GPIO [ 0.074809] sun8i-h3-pinctrl 1c20800.pinctrl: initialized sunXi PIO driver [ 0.076167] sun8i-h3-r-pinctrl 1f02c00.pinctrl: initialized sunXi PIO driver [ 0.148009] ------------[ cut here ]------------ [ 0.148035] WARNING: CPU: 0 PID: 1 at drivers/clk/sunxi-ng/ccu_common.c:41 ccu_nm_set_rate+0x1d0/0x274 [ 0.148046] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.13.0-rc6-next-20170825-aik-aik #24 [ 0.148051] Hardware name: Allwinner sun8i Family [ 0.148082] [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [ 0.148101] [] (show_stack) from [] (dump_stack+0x84/0x98) [ 0.148117] [] (dump_stack) from [] (__warn+0xe0/0xfc) [ 0.148132] [] (__warn) from [] (warn_slowpath_null+0x20/0x28) [ 0.148145] [] (warn_slowpath_null) from [] (ccu_nm_set_rate+0x1d0/0x274) [ 0.148161] [] (ccu_nm_set_rate) from [] (clk_change_rate+0x19c/0x250) [ 0.148175] [] (clk_change_rate) from [] (clk_core_set_rate_nolock+0x68/0xb0) [ 0.148187] [] (clk_core_set_rate_nolock) from [] (clk_set_rate+0x20/0x30) [ 0.148202] [] (clk_set_rate) from [] (of_clk_set_defaults+0x200/0x364) [ 0.148219] [] (of_clk_set_defaults) from [] (platform_drv_probe+0x18/0xb0) [ 0.148233] [] (platform_drv_probe) from [] (driver_probe_device+0x234/0x2e8) [ 0.148246] [] (driver_probe_device) from [] (__driver_attach+0xb8/0xbc) [ 0.148258] [] (__driver_attach) from [