From patchwork Tue Sep 22 14:16:49 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Robin Murphy X-Patchwork-Id: 11792675 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A55F0112C for ; Tue, 22 Sep 2020 14:23:05 +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 34E28239A1 for ; Tue, 22 Sep 2020 14:23:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 34E28239A1 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.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 81C1789F85; Tue, 22 Sep 2020 14:23:01 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by gabe.freedesktop.org (Postfix) with ESMTP id 4D5676E86E for ; Tue, 22 Sep 2020 14:17:01 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C104B12FC; Tue, 22 Sep 2020 07:17:00 -0700 (PDT) Received: from e121345-lin.cambridge.arm.com (e121345-lin.cambridge.arm.com [10.1.196.37]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 363353F718; Tue, 22 Sep 2020 07:16:59 -0700 (PDT) From: Robin Murphy To: will@kernel.org, robh@kernel.org, tomeu.vizoso@collabora.com, steven.price@arm.com, alyssa.rosenzweig@collabora.com, khilman@baylibre.com, narmstrong@baylibre.com, jbrunet@baylibre.com Subject: [PATCH v2 2/3] drm/panfrost: Support cache-coherent integrations Date: Tue, 22 Sep 2020 15:16:49 +0100 Message-Id: <7024ce18c1cb1a226e918037d49175571db0b436.1600780574.git.robin.murphy@arm.com> X-Mailer: git-send-email 2.28.0.dirty In-Reply-To: References: 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-amlogic@lists.infradead.org, iommu@lists.linux-foundation.org, dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" When the GPU's ACE-Lite interface is fully wired up and capable of snooping CPU caches, it may be described as "dma-coherent" in devicetree, which will already inform the DMA layer not to perform unnecessary cache maintenance. However, we still need to ensure that the GPU uses the appropriate cacheable outer-shareable attributes in order to generate the requisite snoop signals, and that CPU mappings don't create a mismatch by using a non-cacheable type either. Reviewed-by: Steven Price Tested-by: Neil Armstrong Signed-off-by: Robin Murphy --- drivers/gpu/drm/panfrost/panfrost_device.h | 1 + drivers/gpu/drm/panfrost/panfrost_drv.c | 2 ++ drivers/gpu/drm/panfrost/panfrost_gem.c | 2 ++ drivers/gpu/drm/panfrost/panfrost_mmu.c | 1 + 4 files changed, 6 insertions(+) diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h b/drivers/gpu/drm/panfrost/panfrost_device.h index c30c719a8059..b31f45315e96 100644 --- a/drivers/gpu/drm/panfrost/panfrost_device.h +++ b/drivers/gpu/drm/panfrost/panfrost_device.h @@ -84,6 +84,7 @@ struct panfrost_device { /* pm_domains for devices with more than one. */ struct device *pm_domain_devs[MAX_PM_DOMAINS]; struct device_link *pm_domain_links[MAX_PM_DOMAINS]; + bool coherent; struct panfrost_features features; const struct panfrost_compatible *comp; diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c b/drivers/gpu/drm/panfrost/panfrost_drv.c index ada51df9a7a3..2a6f2f716b2f 100644 --- a/drivers/gpu/drm/panfrost/panfrost_drv.c +++ b/drivers/gpu/drm/panfrost/panfrost_drv.c @@ -588,6 +588,8 @@ static int panfrost_probe(struct platform_device *pdev) if (!pfdev->comp) return -ENODEV; + pfdev->coherent = device_get_dma_attr(&pdev->dev) == DEV_DMA_COHERENT; + /* Allocate and initialze the DRM device. */ ddev = drm_dev_alloc(&panfrost_drm_driver, &pdev->dev); if (IS_ERR(ddev)) diff --git a/drivers/gpu/drm/panfrost/panfrost_gem.c b/drivers/gpu/drm/panfrost/panfrost_gem.c index 33355dd302f1..cdf1a8754eba 100644 --- a/drivers/gpu/drm/panfrost/panfrost_gem.c +++ b/drivers/gpu/drm/panfrost/panfrost_gem.c @@ -220,6 +220,7 @@ static const struct drm_gem_object_funcs panfrost_gem_funcs = { */ struct drm_gem_object *panfrost_gem_create_object(struct drm_device *dev, size_t size) { + struct panfrost_device *pfdev = dev->dev_private; struct panfrost_gem_object *obj; obj = kzalloc(sizeof(*obj), GFP_KERNEL); @@ -229,6 +230,7 @@ struct drm_gem_object *panfrost_gem_create_object(struct drm_device *dev, size_t INIT_LIST_HEAD(&obj->mappings.list); mutex_init(&obj->mappings.lock); obj->base.base.funcs = &panfrost_gem_funcs; + obj->base.map_cached = pfdev->coherent; return &obj->base.base; } diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c index e8f7b11352d2..8852fd378f7a 100644 --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c @@ -371,6 +371,7 @@ int panfrost_mmu_pgtable_alloc(struct panfrost_file_priv *priv) .pgsize_bitmap = SZ_4K | SZ_2M, .ias = FIELD_GET(0xff, pfdev->features.mmu_features), .oas = FIELD_GET(0xff00, pfdev->features.mmu_features), + .coherent_walk = pfdev->coherent, .tlb = &mmu_tlb_ops, .iommu_dev = pfdev->dev, };