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=-9.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 7D1A9C65BAF for ; Wed, 12 Dec 2018 19:43:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3E16820811 for ; Wed, 12 Dec 2018 19:43:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=amarulasolutions.com header.i=@amarulasolutions.com header.b="Sb05uGfb" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3E16820811 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=amarulasolutions.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727204AbeLLTny (ORCPT ); Wed, 12 Dec 2018 14:43:54 -0500 Received: from mail-it1-f195.google.com ([209.85.166.195]:33908 "EHLO mail-it1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726243AbeLLTny (ORCPT ); Wed, 12 Dec 2018 14:43:54 -0500 Received: by mail-it1-f195.google.com with SMTP id x124so14462596itd.1 for ; Wed, 12 Dec 2018 11:43:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amarulasolutions.com; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=4O6JG1fVoPe87+m+7CKj+JrKSi1kqsDwdZDPItQ/pA0=; b=Sb05uGfbdr7z4FnGnb4D/kUUmIfzmo3odrVflDV1XVuhnZJPmNva5KvEQwonoUjaiB cwUNLq26JgT+KV7RJnvSOp0BHkRj5uFypzqd8Bt49rWLi+riB8+/okVk7ia6P+BsLNoF Y7Zxygg5zGL82coTqYvBobiDl6bdxOyA72YTI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=4O6JG1fVoPe87+m+7CKj+JrKSi1kqsDwdZDPItQ/pA0=; b=lGqPwlHjGSV3GOFwhweSee2nU3o2QvjmE+EWL6APUYjmdOgIErU7/CM1wX4xpDZlIe Raja7zEJquQs9q/AgNLskAjGqNRrWRs2SbaKKPzhqAUhzccCxv9TP83JzhSFvHrxvHhL N1tUyZ6J+LPqE0Mh+YHA8cGNK+Qj0mFj8crKv1M7QSWm6dAyRjSG40TQiSuJcOOSZmk1 8Yt9BOllZ7jN0HXjTUm8HuVNQZA6aHDl2AA2jlzxOQxVkpjIA8iI2cQDCImk6/yUjzGa 5eYq1zqrJzQZN4UQ0Uxn9ufYFgb/lpq339QC/DTnYYW/FX26uktTlkPq0++DLtw3MVWE bE8g== X-Gm-Message-State: AA+aEWY85Fou6196YJqqzXmIei/pqSvZFIXRqFwpQuQavdFMV9aDpDpA nq5t3FyB/bNPWx1hjNgmKkiaCGclamBuNy2q9Ioouw== X-Google-Smtp-Source: AFSGD/WW7e7ICAd+v20UL5gdUicwYrot3Fa4beMJiVhdcY5ooGvbDA8745sOnShAYWDncU9ioD1jjIVU7VpW9Xhq5ps= X-Received: by 2002:a24:4f07:: with SMTP id c7mr7161579itb.107.1544643833171; Wed, 12 Dec 2018 11:43:53 -0800 (PST) MIME-Version: 1.0 References: <20181210161729.29720-1-jagan@amarulasolutions.com> <20181210161729.29720-8-jagan@amarulasolutions.com> <20181211164900.wfmkmbrbj3nmlb3h@flea> In-Reply-To: From: Jagan Teki Date: Thu, 13 Dec 2018 01:13:40 +0530 Message-ID: Subject: Re: [PATCH v5 07/17] drm/sun4i: sun6i_mipi_dsi: Refactor vertical video start delay To: Maxime Ripard Cc: Chen-Yu Tsai , Michael Turquette , Stephen Boyd , linux-arm-kernel , linux-clk , linux-kernel , dri-devel , Michael Trimarchi , linux-sunxi , linux-amarula@amarulasolutions.com Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Maxime, On Tue, Dec 11, 2018 at 10:30 PM Jagan Teki wrote: > > On Tue, Dec 11, 2018 at 10:19 PM Maxime Ripard > wrote: > > > > On Mon, Dec 10, 2018 at 09:47:19PM +0530, Jagan Teki wrote: > > > Video start delay can be computed by subtracting total vertical > > > timing with front porch timing and with adding 1 delay line for TCON. > > > > > > BSP code form BPI-M64-bsp is computing video start delay as > > > (from linux-sunxi/ > > > drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/de_dsi.c) > > > > > > u32 vfp = panel->lcd_vt - panel->lcd_y - panel->lcd_vbp; > > > => (panel->lcd_vt) - panel->lcd_y - (panel->lcd_vbp) > > > => (timmings->ver_front_porch + panel->lcd_vbp + panel->lcd_y) > > > - panel->lcd_y - (panel->lcd_vbp) > > > => timmings->ver_front_porch + panel->lcd_vbp + panel->lcd_y > > > - panel->lcd_y - panel->lcd_vbp > > > => timmings->ver_front_porch > > > > > > So, update the start delay computation accordingly. > > > > > > Signed-off-by: Jagan Teki > > > > Even though it's a bit better now on my A33 board and I don't have the > > white stripes on the bottom of the display, there's still some > > flickering with your patches applied. > > > > Bisecting it seems to point at that patch, but reverting it doesn't > > make the issue go away, so it's not really clear which one exactly is > > at fault. > > > > So, just like I asked in your v4, twice, > > > > http://lists.infradead.org/pipermail/linux-arm-kernel/2018-November/615339.html > > I don't know how can I comment here. Not quite clearly understand your > setup, because I have verified 3 different panels from different > vendors one with 2-lane, another with 4-lane and one with video format > and another one is burstmode format. I even verified with the clock > rate and register details. > > Please suggest me, what can look further on this. >From the BSP point-of-view I couldn't find have any difference in start_delay computation between A64, and A33[1]. In fact the driver initialization code is same, here is A64 dsi driver[2]. 1) The only difference that I observe is dsi_gen_wr in BSP [3], the A33 is right shifting message tx length to 0, 8 for first and next packet where as A64 did the same by adding +1 before. Please try to check that If your panel is using long write. and 2) Also every dsi transaction in A33 occupy some delay code in dsi_gen_wr[4], please check the same. and 3) Also If possible please check your panel timings or initialization sequence, because I don't have any panel with A33. 4) other than these I have didn't notice any differences atleast from my knowledge, Please suggest me where can I look further. [1] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/lowlevel_sun8iw5/de_dsi.c#L813 [2] https://github.com/BPI-SINOVOIP/BPI-M64-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp2/disp/de/lowlevel_sun50iw1/de_dsi.c [3] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/lowlevel_sun8iw5/de_dsi.c#L402 [4] https://github.com/BPI-SINOVOIP/BPI-M2M-bsp/blob/master/linux-sunxi/drivers/video/sunxi/disp/de/lowlevel_sun8iw5/de_dsi.c#L378