From patchwork Thu Jan 14 08:17:32 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Giulio Benetti X-Patchwork-Id: 12018987 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=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 4078EC433E0 for ; Thu, 14 Jan 2021 09:29:45 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id AF07B23741 for ; Thu, 14 Jan 2021 09:29:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AF07B23741 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=benettiengineering.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A153E6E15D; Thu, 14 Jan 2021 09:29:04 +0000 (UTC) Received: from smtpcmd02101.aruba.it (smtpcmd02101.aruba.it [62.149.158.101]) by gabe.freedesktop.org (Postfix) with ESMTP id 5B9486E05F for ; Thu, 14 Jan 2021 08:17:46 +0000 (UTC) Received: from ubuntu.localdomain ([146.241.213.249]) by Aruba Outgoing Smtp with ESMTPSA id zxp6kTFwPytJRzxp7k7D6v; Thu, 14 Jan 2021 09:17:45 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=aruba.it; s=a1; t=1610612265; bh=q9tueK9HEveBIOB8QrMmLAUmWUHC2u5Y0+MdQPVjTIE=; h=From:To:Subject:Date:MIME-Version:Content-Type; b=ewDfyysXYQny7iV4C97hOUvVlJ2OLe14AtC5hSFEgcteYN6eozPt3z5x2Co5jbgyk laP44spnPMwob+qJDmBdyj/RP0HPS8EvWHBnEzkbeheEdqaFAOLmIyD4xY8rFhlois kFmJHKNClAHG+bHxVsNJVRZVgKm3jslI38tW4FGZ5dp5TxvvkBGqJfVQdtuTQK3pIS afmsbAP9hAZ5qRWOeDnG3GImfCtzydZlUKxr/ZheN6jBErwOhNBHozchNf1ihFBFiy kgHVg88AV2U8OtX//wODjT/eXX4VubKekWWQTLRWU0Es2Cq6MHr1vfFuZ1EpY5bru3 Ho8pU85ql+B2g== From: Giulio Benetti To: Maxime Ripard Subject: [PATCH v6] drm/sun4i: tcon: fix inverted DCLK polarity Date: Thu, 14 Jan 2021 09:17:32 +0100 Message-Id: <20210114081732.9386-1-giulio.benetti@benettiengineering.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 X-CMAE-Envelope: MS4wfAGxm1wXP7WDU9n8Y3GoHjUuJw0ErOooXMnbt1lHUamPDJFDY73JmY397X+QMkzt+JIddcsWmy0ToiK6rYPYMssLsfK3GB0ODoH2uUhSe/jo65oJeKEa 09jlDX+51JqJFmb30T5Yp+N3cf7pNvBlEEeeMm/TYHF551iAt/Gz7o2n9euV6CVgW3vpIMxP4NcuWo27vI9BjZhYNSdGJDY5lvLjJr0kJ6yi2XroP9TuR+0D McPqrX4AnQySdF04Hzxvd1fFnQFOi2JRVS9XY5TZdDIT2AAX6VvuzCratmHztgQ9yr+sQzqj5/02FV6mUSaNXMIaI+q3PMF0NNX4doArC1bmZo+CPh6WI3+p tix0d8/mzt8MWlk+vy/R28ssBmnNXWVOW6avcNKxO3V5M0XhqA6EO7mHdGH8WGMKh3Eh4GcsHdpILwpWivaE50j7l5GTw9V+NUQaQ4qGGHkq2s63e1bvWUTm D7EzNRjM/S0i3V5Nti+5tXAamTVWQejgrhNYbEpUQ4biIYIa8Nyzq/bL90WwYFyNIM5f3gvkIi2bAkvR0v14u7YkO443ispsdYLJ6w== X-Mailman-Approved-At: Thu, 14 Jan 2021 09:28:31 +0000 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jernej Skrabec , airlied@linux.ie, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, wens@csie.org, linux-arm-kernel@lists.infradead.org, treding@nvidia.com, Giulio Benetti , Marjan Pascolo Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Giulio Benetti During commit 88bc4178568b ("drm: Use new DRM_BUS_FLAG_*_(DRIVE|SAMPLE)_(POS|NEG)EDGE flags") DRM_BUS_FLAG_* macros have been changed to avoid ambiguity but just because of this ambiguity previous DRM_BUS_FLAG_PIXDATA_(POS/NEG)EDGE were used meaning _SAMPLE_ not _DRIVE_. This leads to DLCK inversion and need to fix but instead of swapping phase values, let's adopt an easier approach Maxime suggested: It turned out that bit 26 of SUN4I_TCON0_IO_POL_REG is dedicated to invert DCLK polarity and this makes things really easier than before. So let's handle DCLK polarity by adding SUN4I_TCON0_IO_POL_DCLK_DRIVE_NEGEDGE as bit 26 and activating according to bus_flags the same way it is done for all the other signals polarity. Fixes: 88bc4178568b ("drm: Use new DRM_BUS_FLAG_*_(DRIVE|SAMPLE)_(POS|NEG)EDGE flags") Suggested-by: Maxime Ripard Signed-off-by: Giulio Benetti Tested-by: Marjan Pascolo --- V2->V3: - squash 2 patches into 1 V3->V4: - add SUN4I_TCON0_IO_POL_DCLK_POSITIVE to regmap_update_bits() as suggested by Maxime V4->V5: polarity is still wrong so: - let's use SUN4I_TCON0_IO_POL_DCLK_DRIVE_NEGEDGE macro instead of _DCLK_POSITIVE(that would make sense only in realtion with DCLK) - invert condition using _NEGEDGE instead of _POSEDGE and then matching with register bit SUN4I_TCON0_IO_POL_DCLK_DRIVE_NEGEDGE - correct commit log according to V4->V5 changes V5->V6: - fix typo in SUN4I_TCON0_IO_POL_DCLK_DRIVE_NEGEDGE as suggested by Marjan --- drivers/gpu/drm/sun4i/sun4i_tcon.c | 21 ++------------------- drivers/gpu/drm/sun4i/sun4i_tcon.h | 1 + 2 files changed, 3 insertions(+), 19 deletions(-) diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c index eaaf5d70e352..6b9af4c08cd6 100644 --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c @@ -569,30 +569,13 @@ static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon, if (info->bus_flags & DRM_BUS_FLAG_DE_LOW) val |= SUN4I_TCON0_IO_POL_DE_NEGATIVE; - /* - * On A20 and similar SoCs, the only way to achieve Positive Edge - * (Rising Edge), is setting dclk clock phase to 2/3(240°). - * By default TCON works in Negative Edge(Falling Edge), - * this is why phase is set to 0 in that case. - * Unfortunately there's no way to logically invert dclk through - * IO_POL register. - * The only acceptable way to work, triple checked with scope, - * is using clock phase set to 0° for Negative Edge and set to 240° - * for Positive Edge. - * On A33 and similar SoCs there would be a 90° phase option, - * but it divides also dclk by 2. - * Following code is a way to avoid quirks all around TCON - * and DOTCLOCK drivers. - */ - if (info->bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE) - clk_set_phase(tcon->dclk, 240); - if (info->bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE) - clk_set_phase(tcon->dclk, 0); + val |= SUN4I_TCON0_IO_POL_DCLK_DRIVE_NEGEDGE; regmap_update_bits(tcon->regs, SUN4I_TCON0_IO_POL_REG, SUN4I_TCON0_IO_POL_HSYNC_POSITIVE | SUN4I_TCON0_IO_POL_VSYNC_POSITIVE | + SUN4I_TCON0_IO_POL_DCLK_DRIVE_NEGEDGE | SUN4I_TCON0_IO_POL_DE_NEGATIVE, val); diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.h b/drivers/gpu/drm/sun4i/sun4i_tcon.h index cfbf4e6c1679..c5ac1b02482c 100644 --- a/drivers/gpu/drm/sun4i/sun4i_tcon.h +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.h @@ -113,6 +113,7 @@ #define SUN4I_TCON0_IO_POL_REG 0x88 #define SUN4I_TCON0_IO_POL_DCLK_PHASE(phase) ((phase & 3) << 28) #define SUN4I_TCON0_IO_POL_DE_NEGATIVE BIT(27) +#define SUN4I_TCON0_IO_POL_DCLK_DRIVE_NEGEDGE BIT(26) #define SUN4I_TCON0_IO_POL_HSYNC_POSITIVE BIT(25) #define SUN4I_TCON0_IO_POL_VSYNC_POSITIVE BIT(24)