diff options
Diffstat (limited to 'drm-enable-uncached-DMA-optimization-for-ARM-and-arm64.patch')
| -rw-r--r-- | drm-enable-uncached-DMA-optimization-for-ARM-and-arm64.patch | 196 |
1 files changed, 0 insertions, 196 deletions
diff --git a/drm-enable-uncached-DMA-optimization-for-ARM-and-arm64.patch b/drm-enable-uncached-DMA-optimization-for-ARM-and-arm64.patch deleted file mode 100644 index 5e151ce57..000000000 --- a/drm-enable-uncached-DMA-optimization-for-ARM-and-arm64.patch +++ /dev/null @@ -1,196 +0,0 @@ -From patchwork Thu Jan 24 12:06:58 2019 -Content-Type: text/plain; charset="utf-8" -MIME-Version: 1.0 -Content-Transfer-Encoding: 7bit -X-Patchwork-Submitter: Ard Biesheuvel <ard.biesheuvel@linaro.org> -X-Patchwork-Id: 10778815 -Return-Path: - <linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org> -Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org - [172.30.200.125]) - by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B27A191E - for <patchwork-linux-arm@patchwork.kernel.org>; - Thu, 24 Jan 2019 12:07:20 +0000 (UTC) -Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) - by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DFBE72EC6C - for <patchwork-linux-arm@patchwork.kernel.org>; - Thu, 24 Jan 2019 12:07:17 +0000 (UTC) -Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) - id D30BC2ECE2; Thu, 24 Jan 2019 12:07:17 +0000 (UTC) -X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on - pdx-wl-mail.web.codeaurora.org -X-Spam-Level: -X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, - DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 -Received: from bombadil.infradead.org (bombadil.infradead.org - [198.137.202.133]) - (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) - (No client certificate requested) - by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id C03122EC6C - for <patchwork-linux-arm@patchwork.kernel.org>; - Thu, 24 Jan 2019 12:07:16 +0000 (UTC) -DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; - d=lists.infradead.org; s=bombadil.20170209; h=Sender: - Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: - List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:To - :From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: - Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: - List-Owner; bh=xo5AgoUtS0FBdf9ZXAO75L7eu+GEGqebznBMcwnNXS0=; b=EUK2XskaTLLGNd - PLBm/AVgfZr2j3GzaOOAh6rJqVHuQ4k98saArkFu8aSFtVkvkSPF3PKCDKnV+7mZibl17Kqiup2Cv - HsRzfxwZzeksoNjDcZMYK82pttYA+iizpIYq16Wp+SXMzm6HRuku9XhW7tygG9zNr+cUVzaN6QU6b - mO5CAPgeGsluExNwC+4i4fRNqtN4z7rTMPuHkZ6jSy6tTy/OyKUApjhrgphDWEjtelAKeqn8Jwg+i - YnZQMi8l6B4Ffn7IlU2wHVKU7/yk9hO46AC+uKKYTV5RmcC0xFqKNK0TnBQzum5FdK2/h7h/3f0CA - GflIczkPfOItaFoJvs3g==; -Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) - by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) - id 1gmdmr-0000p2-1K; Thu, 24 Jan 2019 12:07:13 +0000 -Received: from mail-wm1-x341.google.com ([2a00:1450:4864:20::341]) - by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) - id 1gmdmm-0000oP-Sk - for linux-arm-kernel@lists.infradead.org; Thu, 24 Jan 2019 12:07:11 +0000 -Received: by mail-wm1-x341.google.com with SMTP id b11so2875125wmj.1 - for <linux-arm-kernel@lists.infradead.org>; - Thu, 24 Jan 2019 04:07:07 -0800 (PST) -DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; - h=from:to:cc:subject:date:message-id:mime-version - :content-transfer-encoding; - bh=GsPSU83pbk1uWSobF359Hmb25tSiPCSXYSiAdhiX2K0=; - b=MVHv9eioSsA83BVb2J9fi21oGdNAhe8L5mYX67nd+XBNW59IxbYWyPCjLtaUXXFxQx - C8eDCimc2jtV5LiHYUHkJKhoQYN40/4u2K6EOoUunE10yy3C+J6aGY9JX5gh7mgstcNp - Dvdm9CHYXs35/N3s4bzP1fUHVnLbpVKVammw0= -X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; - d=1e100.net; s=20161025; - h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version - :content-transfer-encoding; - bh=GsPSU83pbk1uWSobF359Hmb25tSiPCSXYSiAdhiX2K0=; - b=DtNKUeOnwDAjpgolmP7hnQugxkX3XqgSxg6WUAlVeQyxIk+8QlEAWLNFtKPL57EnLP - G9R1qiTnF1TI4PM8DFH+URNkVNcI9hvhGKtO4fya+BjPd6dqPJVwct1+KZWM8lTJfDX+ - pMKL1ZiDeYMlHAMkd2CfCckaEptq5FjtvwJ8pyPbdN5qNxVJ6CEPIl9HORWWMuwrsxaj - xo5MK/UpOqhomOXRe5WxGor2JPNit68hT1PvHQwqNXCoRRTtCUANoV7s1nJ2Ad+pkhV7 - FW5IV/JnVetKbeCIhe2I/m6VlJ+6x3wPOpiWN/Fd8z5tYX0zI0vjKqdjdfr/QJCNF69Z - +cuw== -X-Gm-Message-State: AJcUukcCDAeH11orvgS33hS4OKLhp1Vglp0ChrGS5Ol91KaBPDqURaLX - WKQRIEAwB4phU3pS/I/nkTBzdQ== -X-Google-Smtp-Source: - ALg8bN55gm82WRKfoWS5g8dy3rATbR8W4MaKwupN1EALKBkI9t9KdMSE60V2HSnI4wy7yU44++cGoA== -X-Received: by 2002:a1c:bdc5:: with SMTP id n188mr2530824wmf.69.1548331626262; - Thu, 24 Jan 2019 04:07:06 -0800 (PST) -Received: from localhost.localdomain - (laubervilliers-657-1-83-120.w92-154.abo.wanadoo.fr. [92.154.90.120]) - by smtp.gmail.com with ESMTPSA id t12sm98842348wrr.65.2019.01.24.04.07.04 - (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); - Thu, 24 Jan 2019 04:07:05 -0800 (PST) -From: Ard Biesheuvel <ard.biesheuvel@linaro.org> -To: linux-kernel@vger.kernel.org -Subject: [PATCH] drm: enable uncached DMA optimization for ARM and arm64 -Date: Thu, 24 Jan 2019 13:06:58 +0100 -Message-Id: <20190124120658.30288-1-ard.biesheuvel@linaro.org> -X-Mailer: git-send-email 2.20.1 -MIME-Version: 1.0 -X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 -X-CRM114-CacheID: sfid-20190124_040708_952827_D4810358 -X-CRM114-Status: GOOD ( 13.64 ) -X-BeenThere: linux-arm-kernel@lists.infradead.org -X-Mailman-Version: 2.1.21 -Precedence: list -List-Id: <linux-arm-kernel.lists.infradead.org> -List-Unsubscribe: - <http://lists.infradead.org/mailman/options/linux-arm-kernel>, - <mailto:linux-arm-kernel-request@lists.infradead.org?subject=unsubscribe> -List-Archive: <http://lists.infradead.org/pipermail/linux-arm-kernel/> -List-Post: <mailto:linux-arm-kernel@lists.infradead.org> -List-Help: <mailto:linux-arm-kernel-request@lists.infradead.org?subject=help> -List-Subscribe: - <http://lists.infradead.org/mailman/listinfo/linux-arm-kernel>, - <mailto:linux-arm-kernel-request@lists.infradead.org?subject=subscribe> -Cc: David Zhou <David1.Zhou@amd.com>, - Maxime Ripard <maxime.ripard@bootlin.com>, - Benjamin Herrenschmidt <benh@kernel.crashing.org>, - Carsten Haitzler <Carsten.Haitzler@arm.com>, - Ard Biesheuvel <ard.biesheuvel@linaro.org>, David Airlie <airlied@linux.ie>, - Maarten Lankhorst <maarten.lankhorst@linux.intel.com>, - dri-devel <dri-devel@lists.freedesktop.org>, - Michel Daenzer <michel.daenzer@amd.com>, Robin Murphy <robin.murphy@arm.com>, - Will Deacon <will.deacon@arm.com>, Christoph Hellwig <hch@infradead.org>, - Junwei Zhang <Jerry.Zhang@amd.com>, Huang Rui <ray.huang@amd.com>, - amd-gfx list <amd-gfx@lists.freedesktop.org>, - Daniel Vetter <daniel@ffwll.ch>, - Michael Ellerman <mpe@ellerman.id.au>, - Alex Deucher <alexander.deucher@amd.com>, Sean Paul <sean@poorly.run>, - Christian Koenig <christian.koenig@amd.com>, - linux-arm-kernel@lists.infradead.org -Content-Type: text/plain; charset="us-ascii" -Sender: "linux-arm-kernel" <linux-arm-kernel-bounces@lists.infradead.org> -Errors-To: - linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org -X-Virus-Scanned: ClamAV using ClamSMTP - -The DRM driver stack is designed to work with cache coherent devices -only, but permits an optimization to be enabled in some cases, where -for some buffers, both the CPU and the GPU use uncached mappings, -removing the need for DMA snooping and allocation in the CPU caches. - -The use of uncached GPU mappings relies on the correct implementation -of the PCIe NoSnoop TLP attribute by the platform, otherwise the GPU -will use cached mappings nonetheless. On x86 platforms, this does not -seem to matter, as uncached CPU mappings will snoop the caches in any -case. However, on ARM and arm64, enabling this optimization on a -platform where NoSnoop is ignored results in loss of coherency, which -breaks correct operation of the device. Since we have no way of -detecting whether NoSnoop works or not, just disable this -optimization entirely for ARM and arm64. - -Cc: Christian Koenig <christian.koenig@amd.com> -Cc: Alex Deucher <alexander.deucher@amd.com> -Cc: David Zhou <David1.Zhou@amd.com> -Cc: Huang Rui <ray.huang@amd.com> -Cc: Junwei Zhang <Jerry.Zhang@amd.com> -Cc: Michel Daenzer <michel.daenzer@amd.com> -Cc: David Airlie <airlied@linux.ie> -Cc: Daniel Vetter <daniel@ffwll.ch> -Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> -Cc: Maxime Ripard <maxime.ripard@bootlin.com> -Cc: Sean Paul <sean@poorly.run> -Cc: Michael Ellerman <mpe@ellerman.id.au> -Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> -Cc: Will Deacon <will.deacon@arm.com> -Cc: Christoph Hellwig <hch@infradead.org> -Cc: Robin Murphy <robin.murphy@arm.com> -Cc: amd-gfx list <amd-gfx@lists.freedesktop.org> -Cc: dri-devel <dri-devel@lists.freedesktop.org> -Reported-by: Carsten Haitzler <Carsten.Haitzler@arm.com> -Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> -Reviewed-by: Alex Deucher <alexander.deucher@amd.com> ---- - include/drm/drm_cache.h | 18 ++++++++++++++++++ - 1 file changed, 18 insertions(+) - -diff --git a/include/drm/drm_cache.h b/include/drm/drm_cache.h -index bfe1639df02d..97fc498dc767 100644 ---- a/include/drm/drm_cache.h -+++ b/include/drm/drm_cache.h -@@ -47,6 +47,24 @@ static inline bool drm_arch_can_wc_memory(void) - return false; - #elif defined(CONFIG_MIPS) && defined(CONFIG_CPU_LOONGSON3) - return false; -+#elif defined(CONFIG_ARM) || defined(CONFIG_ARM64) -+ /* -+ * The DRM driver stack is designed to work with cache coherent devices -+ * only, but permits an optimization to be enabled in some cases, where -+ * for some buffers, both the CPU and the GPU use uncached mappings, -+ * removing the need for DMA snooping and allocation in the CPU caches. -+ * -+ * The use of uncached GPU mappings relies on the correct implementation -+ * of the PCIe NoSnoop TLP attribute by the platform, otherwise the GPU -+ * will use cached mappings nonetheless. On x86 platforms, this does not -+ * seem to matter, as uncached CPU mappings will snoop the caches in any -+ * case. However, on ARM and arm64, enabling this optimization on a -+ * platform where NoSnoop is ignored results in loss of coherency, which -+ * breaks correct operation of the device. Since we have no way of -+ * detecting whether NoSnoop works or not, just disable this -+ * optimization entirely for ARM and arm64. -+ */ -+ return false; - #else - return true; - #endif |