From patchwork Thu Apr 21 04:15:50 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bjorn Andersson X-Patchwork-Id: 564564 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CF6B8C4332F for ; Thu, 21 Apr 2022 04:13:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231648AbiDUEQk (ORCPT ); Thu, 21 Apr 2022 00:16:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53698 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1384064AbiDUEQj (ORCPT ); Thu, 21 Apr 2022 00:16:39 -0400 Received: from mail-oa1-x2c.google.com (mail-oa1-x2c.google.com [IPv6:2001:4860:4864:20::2c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3F2CCE0DD for ; Wed, 20 Apr 2022 21:13:49 -0700 (PDT) Received: by mail-oa1-x2c.google.com with SMTP id 586e51a60fabf-e656032735so2947797fac.0 for ; Wed, 20 Apr 2022 21:13:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=YxJkE8G1CRaDGILe7+GoWJTE8swqHANzIKXbTjCxfWA=; b=wmc+QCZr7W/1S6Qi4m8vCRTullRSJITUAjG2JkXsl8y5jZBmRrU28R4meMbAFMy3j4 xQHQfXWzBZdgs6/PiN1QjCK7nca7KkIULjqpfArwqsljTp9SwXfgOAPvYa/92cfETLAO LH346HKowgQBSMij8Rm6I/QklFiHzmza27cpSEJEdeZ83KaCQ/3QihpNz/jZGXDcdZXB rgfhCdFLPpwEhmrawwEsfA7x/XzslBP9+9jEx720HPu5cdO5e9TWoRCQ+S0ou0bYepRe DpwKKaqQtinBGgGsOfZBxZeQVVlZTAvWQhsNDyFZh2IskOh9wH/UhEVMJURzOankc7i2 6Jog== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=YxJkE8G1CRaDGILe7+GoWJTE8swqHANzIKXbTjCxfWA=; b=ejDKid5cd5zBIRJwEZD4R51V11OG2apzglc4PHS1ZXgC06241XcGpZK5MSk24XTiFc tl6NAso5hKdZI4hLxtotZs9qWHVFnM4MGq0ER5yRBi4VYVkZTW282inYIvjlK6dLi3I7 UinxrBRWr/cyV+NDvH1yJD5gvnspQsDgrvqmFASG10NJT8AhNwjIXYI3ZK/lTtcV14z6 4h9ndEsN3djO13Zja+Q301xUNIQrgvPgsLRx/yZIxeYMWXx4DLzrrGoxuP5TgeYbLRbe DfLBG92psdsfy9XWXN4NWXwC/mtWO4c1TMPVTVRk9F3rLg+27gNKK50DNWIP8PJecOaH kAqQ== X-Gm-Message-State: AOAM532nQNGMia5brmv0JbY0wtdBuJAIt86uU7W61qeqANIHtR9Czpn5 ARUKDIwiSGxFF/y4lZsrvSbSFw== X-Google-Smtp-Source: ABdhPJwj+TTo8+SybVk/1ckcBy63VRtH0SyOXR6xQENQRDdLYgNccjsgslQORDGkN774JfFw5rMNyQ== X-Received: by 2002:a05:6870:a707:b0:e2:cc85:d98 with SMTP id g7-20020a056870a70700b000e2cc850d98mr3085213oam.131.1650514427764; Wed, 20 Apr 2022 21:13:47 -0700 (PDT) Received: from ripper.. ([2600:1700:a0:3dc8:205:1bff:fec0:b9b3]) by smtp.gmail.com with ESMTPSA id h186-20020acab7c3000000b002ef5106248asm7115512oif.45.2022.04.20.21.13.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Apr 2022 21:13:47 -0700 (PDT) From: Bjorn Andersson To: Rob Clark , Abhinav Kumar , Rob Herring , Krzysztof Kozlowski , Dmitry Baryshkov Cc: Sean Paul , David Airlie , Daniel Vetter , Philipp Zabel , linux-arm-msm@vger.kernel.org, dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v4 2/2] drm/msm/dpu: Issue MDSS reset during initialization Date: Wed, 20 Apr 2022 21:15:50 -0700 Message-Id: <20220421041550.643964-2-bjorn.andersson@linaro.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220421041550.643964-1-bjorn.andersson@linaro.org> References: <20220421041550.643964-1-bjorn.andersson@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org It's typical for the bootloader to bring up the display for showing a boot splash or efi framebuffer. But in some cases the kernel driver ends up only partially configuring (in particular) the DPU, which might result in e.g. that two different data paths attempts to push data to the interface - with resulting graphical artifacts. Naturally the end goal would be to inherit the bootloader's configuration and provide the user with a glitch free handover from the boot configuration to a running DPU. But as implementing seamless transition from the bootloader configuration to the running OS will be a considerable effort, start by simply resetting the entire MDSS to its power-on state, to avoid the partial configuration. Signed-off-by: Bjorn Andersson Reviewed-by: Dmitry Baryshkov --- Changes since v3: - Rebased upon the mdss dpu/mdp restructuring (https://patchwork.freedesktop.org/series/98525/) drivers/gpu/drm/msm/msm_mdss.c | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/drivers/gpu/drm/msm/msm_mdss.c b/drivers/gpu/drm/msm/msm_mdss.c index f6f0d0fa5ab2..20f154dda9cf 100644 --- a/drivers/gpu/drm/msm/msm_mdss.c +++ b/drivers/gpu/drm/msm/msm_mdss.c @@ -4,11 +4,13 @@ */ #include +#include #include #include #include #include #include +#include #include "msm_drv.h" #include "msm_kms.h" @@ -193,6 +195,32 @@ static void msm_mdss_destroy(struct msm_mdss *msm_mdss) irq_set_chained_handler_and_data(irq, NULL, NULL); } +static int msm_mdss_reset(struct device *dev) +{ + struct reset_control *reset; + + reset = reset_control_get_optional_exclusive(dev, NULL); + if (!reset) { + /* Optional reset not specified */ + return 0; + } else if (IS_ERR(reset)) { + return dev_err_probe(dev, PTR_ERR(reset), + "failed to acquire mdss reset\n"); + } + + reset_control_assert(reset); + /* + * Tests indicate that reset has to be held for some period of time, + * make it one frame in a typical system + */ + msleep(20); + reset_control_deassert(reset); + + reset_control_put(reset); + + return 0; +} + /* * MDP5 MDSS uses at most three specified clocks. */ @@ -229,6 +257,10 @@ static struct msm_mdss *msm_mdss_init(struct platform_device *pdev, bool is_mdp5 int ret; int irq; + ret = msm_mdss_reset(&pdev->dev); + if (ret) + return ERR_PTR(ret); + msm_mdss = devm_kzalloc(&pdev->dev, sizeof(*msm_mdss), GFP_KERNEL); if (!msm_mdss) return ERR_PTR(-ENOMEM);