From patchwork Thu Nov 2 14:26:40 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: AngeloGioacchino Del Regno X-Patchwork-Id: 13443806 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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id E6814C4167B for ; Thu, 2 Nov 2023 14:27:05 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C851710E8CE; Thu, 2 Nov 2023 14:26:57 +0000 (UTC) Received: from madras.collabora.co.uk (madras.collabora.co.uk [46.235.227.172]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9E66910E8CD for ; Thu, 2 Nov 2023 14:26:55 +0000 (UTC) Received: from IcarusMOD.eternityproject.eu (cola.collaboradmins.com [195.201.22.229]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: kholk11) by madras.collabora.co.uk (Postfix) with ESMTPSA id 9461A66071A3; Thu, 2 Nov 2023 14:26:53 +0000 (GMT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1698935214; bh=/LtYZX88iauWNQZJUo4rCxgbBpDr9xze3AUhEtbVTX4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lvCYDqjfsnlTfsTUF/eGRTtWeN06O3QFIIgwOJE09mRbW8MjPHG1/i43A+8/nblLF p+E3VMrHJD5qpmnaxqxCumtS1z2BrlDmtmX8sk/GycpwBkjj+DglrTVqL4sFFaVcIA mDY8v7I6SxgubAArRmtIzOscjqMEmow1sr9XbJfDrmYhrw5bd/8a25/isvw4Vd+EB2 PnGNLBcJVqguD8Dtf+wt87G6W3LOzTvN+WdZgVQ0+DSpDYcbGjeqlj7xJZzGvIhT/D yi2c43PAITxkqG1psxvhQyXW1jUSq2TUp4v7ohJYSBW0qvrUY40AqbmX11RD9UlA1A sJI57ISmuQnLQ== From: AngeloGioacchino Del Regno To: boris.brezillon@collabora.com Subject: [PATCH v2 3/6] drm/panfrost: Implement ability to turn on/off GPU clocks in suspend Date: Thu, 2 Nov 2023 15:26:40 +0100 Message-ID: <20231102142643.75288-4-angelogioacchino.delregno@collabora.com> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231102142643.75288-1-angelogioacchino.delregno@collabora.com> References: <20231102142643.75288-1-angelogioacchino.delregno@collabora.com> MIME-Version: 1.0 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: linux-kernel@vger.kernel.org, mripard@kernel.org, steven.price@arm.com, dri-devel@lists.freedesktop.org, tzimmermann@suse.de, wenst@chromium.org, kernel@collabora.com, AngeloGioacchino Del Regno Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Currently, the GPU is being internally powered off for runtime suspend and turned back on for runtime resume through commands sent to it, but note that the GPU doesn't need to be clocked during the poweroff state, hence it is possible to save some power on selected platforms. Add suspend and resume handlers for full system sleep and then add a new panfrost_gpu_pm enumeration and a pm_features variable in the panfrost_compatible structure: BIT(GPU_PM_CLK_DIS) will be used to enable this power saving technique only on SoCs that are able to safely use it. Note that this was implemented only for the system sleep case and not for runtime PM because testing on one of my MediaTek platforms showed issues when turning on and off clocks aggressively (in PM runtime) resulting in a full system lockup. Doing this only for full system sleep never showed issues during my testing by suspending and resuming the system continuously for more than 100 cycles. Signed-off-by: AngeloGioacchino Del Regno Reviewed-by: Steven Price --- Note: Even after fixing the panfrost_power_off() function, I'm still getting issues with turning off the clocks at .runtime_suspend() but this time, instead of getting a GPU lockup, the entire SoC will deadlock bringing down the entire system with it (so it's even worst!) :-) drivers/gpu/drm/panfrost/panfrost_device.c | 61 ++++++++++++++++++++-- drivers/gpu/drm/panfrost/panfrost_device.h | 11 ++++ 2 files changed, 68 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/panfrost/panfrost_device.c b/drivers/gpu/drm/panfrost/panfrost_device.c index 28f7046e1b1a..2022ed76a620 100644 --- a/drivers/gpu/drm/panfrost/panfrost_device.c +++ b/drivers/gpu/drm/panfrost/panfrost_device.c @@ -403,7 +403,7 @@ void panfrost_device_reset(struct panfrost_device *pfdev) panfrost_job_enable_interrupts(pfdev); } -static int panfrost_device_resume(struct device *dev) +static int panfrost_device_runtime_resume(struct device *dev) { struct panfrost_device *pfdev = dev_get_drvdata(dev); @@ -413,7 +413,7 @@ static int panfrost_device_resume(struct device *dev) return 0; } -static int panfrost_device_suspend(struct device *dev) +static int panfrost_device_runtime_suspend(struct device *dev) { struct panfrost_device *pfdev = dev_get_drvdata(dev); @@ -426,5 +426,58 @@ static int panfrost_device_suspend(struct device *dev) return 0; } -EXPORT_GPL_RUNTIME_DEV_PM_OPS(panfrost_pm_ops, panfrost_device_suspend, - panfrost_device_resume, NULL); +static int panfrost_device_resume(struct device *dev) +{ + struct panfrost_device *pfdev = dev_get_drvdata(dev); + int ret; + + if (pfdev->comp->pm_features & BIT(GPU_PM_CLK_DIS)) { + ret = clk_enable(pfdev->clock); + if (ret) + return ret; + + if (pfdev->bus_clock) { + ret = clk_enable(pfdev->bus_clock); + if (ret) + goto err_bus_clk; + } + } + + ret = pm_runtime_force_resume(dev); + if (ret) + goto err_resume; + + return 0; + +err_resume: + if (pfdev->comp->pm_features & BIT(GPU_PM_CLK_DIS) && pfdev->bus_clock) + clk_disable(pfdev->bus_clock); +err_bus_clk: + if (pfdev->comp->pm_features & BIT(GPU_PM_CLK_DIS)) + clk_disable(pfdev->clock); + return ret; +} + +static int panfrost_device_suspend(struct device *dev) +{ + struct panfrost_device *pfdev = dev_get_drvdata(dev); + int ret; + + ret = pm_runtime_force_suspend(dev); + if (ret) + return ret; + + if (pfdev->comp->pm_features & BIT(GPU_PM_CLK_DIS)) { + clk_disable(pfdev->clock); + + if (pfdev->bus_clock) + clk_disable(pfdev->bus_clock); + } + + return 0; +} + +EXPORT_GPL_DEV_PM_OPS(panfrost_pm_ops) = { + RUNTIME_PM_OPS(panfrost_device_runtime_suspend, panfrost_device_runtime_resume, NULL) + SYSTEM_SLEEP_PM_OPS(panfrost_device_suspend, panfrost_device_resume) +}; diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h b/drivers/gpu/drm/panfrost/panfrost_device.h index 1ef38f60d5dc..d7f179eb8ea3 100644 --- a/drivers/gpu/drm/panfrost/panfrost_device.h +++ b/drivers/gpu/drm/panfrost/panfrost_device.h @@ -25,6 +25,14 @@ struct panfrost_perfcnt; #define NUM_JOB_SLOTS 3 #define MAX_PM_DOMAINS 5 +/** + * enum panfrost_gpu_pm - Supported kernel power management features + * @GPU_PM_CLK_DIS: Allow disabling clocks during system suspend + */ +enum panfrost_gpu_pm { + GPU_PM_CLK_DIS, +}; + struct panfrost_features { u16 id; u16 revision; @@ -75,6 +83,9 @@ struct panfrost_compatible { /* Vendor implementation quirks callback */ void (*vendor_quirk)(struct panfrost_device *pfdev); + + /* Allowed PM features */ + u8 pm_features; }; struct panfrost_device {