From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751677AbcFWJz0 (ORCPT ); Thu, 23 Jun 2016 05:55:26 -0400 Received: from fw-tnat.cambridge.arm.com ([217.140.96.140]:56425 "EHLO cam-smtp0.cambridge.arm.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751504AbcFWJzX (ORCPT ); Thu, 23 Jun 2016 05:55:23 -0400 From: Punit Agrawal To: Ard Biesheuvel Cc: nouveau@lists.freedesktop.org, dri-devel@lists.freedesktop.org, bskeggs@redhat.com, airlied@linux.ie, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH] drm/nouveau/fb/nv50: set DMA mask before mapping scratch page References: <1466425804-7229-1-git-send-email-ard.biesheuvel@linaro.org> Date: Thu, 23 Jun 2016 10:55:11 +0100 In-Reply-To: <1466425804-7229-1-git-send-email-ard.biesheuvel@linaro.org> (Ard Biesheuvel's message of "Mon, 20 Jun 2016 14:30:04 +0200") Message-ID: <87a8ic44cg.fsf@e105922-lin.cambridge.arm.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.5 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Ard Biesheuvel writes: > The 100c08 scratch page is mapped using dma_map_page() before the TTM > layer has had a chance to set the DMA mask. This means we are still > running with the default of 32 when this code executes, and this causes > problems for platforms with no memory below 4 GB (such as AMD Seattle) > > So move the dma_map_page() to the .init hook, and set the streaming DMA > mask based on the MMU subdev parameters before performing the call. > > Signed-off-by: Ard Biesheuvel Hi Ard, Thanks for posting this patch. With the patch, I am able to see console output on a screen attached to the NVS 300 PCIe card in an AMD Seattle system. It was failing with a message similar to what you've posted below. For some reason, X refuses to start up but that, I think, is a problem with my userspace setup. Cheers, Punit [...]