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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 315F3C282C8 for ; Mon, 28 Jan 2019 17:29:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F34422147A for ; Mon, 28 Jan 2019 17:29:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548696576; bh=Ru2iY6QwaG4AzxIx3U2e7jA9yB0+C7uyLouWhzd/ilw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=iQCjtuA6Ueus/nYJjDj0RyygFiLMlUCmw7reKbQWD5FlyTHeU4lybe+Kw4PqQs4qV Y/9dZF3HRs+BXkbsK53Ax/BGlECeAXCqquEub2HEn9E1MUtAiptHfBKRvsa6jZR+dC cJKZgf2RihiK/ksoi6i5Okt5K0Y6wiXTdFmb/OsQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730996AbfA1R3e (ORCPT ); Mon, 28 Jan 2019 12:29:34 -0500 Received: from mail.kernel.org ([198.145.29.99]:45054 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730622AbfA1P7r (ORCPT ); Mon, 28 Jan 2019 10:59:47 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 68E702082E; Mon, 28 Jan 2019 15:59:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548691186; bh=Ru2iY6QwaG4AzxIx3U2e7jA9yB0+C7uyLouWhzd/ilw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OQMAknXcfeYIGj0suu0xQPZIPY5ctcNAFMMOSbmlESrRRgHggtwDqQMP40nYce1sa 7EgOf42XIt7foRpxGNKn86LDMPORQuFQB6526m63o7t7tY6vlm0Z3YJZxn9EvlK9dV ZYHgKKNGT1nx/eokvJmLUv7wQY4Dk7Aya8o0GyqY= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Jernej Skrabec , Maxime Ripard , Sasha Levin , dri-devel@lists.freedesktop.org Subject: [PATCH AUTOSEL 4.19 007/258] drm/sun4i: Initialize registers in tcon-top driver Date: Mon, 28 Jan 2019 10:55:13 -0500 Message-Id: <20190128155924.51521-7-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190128155924.51521-1-sashal@kernel.org> References: <20190128155924.51521-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jernej Skrabec [ Upstream commit c96d62215fb540e2ae61de44cb7caf4db50958e3 ] It turns out that TCON TOP registers in H6 SoC have non-zero reset value. This may cause issues if bits are not changed during configuration. To prevent that, initialize registers to 0. Signed-off-by: Jernej Skrabec Signed-off-by: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/20181104182705.18047-24-jernej.skrabec@siol.net Signed-off-by: Sasha Levin --- drivers/gpu/drm/sun4i/sun8i_tcon_top.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/gpu/drm/sun4i/sun8i_tcon_top.c b/drivers/gpu/drm/sun4i/sun8i_tcon_top.c index d5240b777a8f..adcdf946c365 100644 --- a/drivers/gpu/drm/sun4i/sun8i_tcon_top.c +++ b/drivers/gpu/drm/sun4i/sun8i_tcon_top.c @@ -168,6 +168,13 @@ static int sun8i_tcon_top_bind(struct device *dev, struct device *master, goto err_assert_reset; } + /* + * At least on H6, some registers have some bits set by default + * which may cause issues. Clear them here. + */ + writel(0, regs + TCON_TOP_PORT_SEL_REG); + writel(0, regs + TCON_TOP_GATE_SRC_REG); + /* * TCON TOP has two muxes, which select parent clock for each TCON TV * channel clock. Parent could be either TCON TV or TVE clock. For now -- 2.19.1