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=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,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 78619C282D7 for ; Mon, 11 Feb 2019 14:39:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3E13B2082F for ; Mon, 11 Feb 2019 14:39:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549895970; bh=ywSlGih1xJ1zeJ0aRYg854WIFpWbT+2j4njnGz2CsYA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ysemmgwfOTRQW13vV/R5SubIZEvwXOUQa41m5KGopRNTm5DPpoTEab+M049wfgUse w7dOmAS+m5UNihfTWSWXjWCRuSDBW2cRobBPHMCaUpyePIQNM2i4jJIOxyhZSZ/ihj 5wsuBX2qv+fTBtslsw/uKnTluR7xtuOFI8Temgck= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731880AbfBKOjY (ORCPT ); Mon, 11 Feb 2019 09:39:24 -0500 Received: from mail.kernel.org ([198.145.29.99]:49626 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728002AbfBKOjW (ORCPT ); Mon, 11 Feb 2019 09:39:22 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E7F3320700; Mon, 11 Feb 2019 14:39:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549895962; bh=ywSlGih1xJ1zeJ0aRYg854WIFpWbT+2j4njnGz2CsYA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UfxN61y6kVHL1GNZrHAR9aVkf3wEA/9XmlRc/r72JezH6HKsPcMUd78eeEik6/bje WXI7s6lIRLRbkNZVskYoVIOxDZv4RF+qHm96s79v5vl/9Tbg02opYsshpdF3ftB8TM uOSpaQL6nhJWpCaSjNNgzoJuWnjnqBniAAzxgAKY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jernej Skrabec , Maxime Ripard , Sasha Levin Subject: [PATCH 4.19 008/313] drm/sun4i: Initialize registers in tcon-top driver Date: Mon, 11 Feb 2019 15:14:48 +0100 Message-Id: <20190211141853.481248310@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190211141852.749630980@linuxfoundation.org> References: <20190211141852.749630980@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ [ 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