From mboxrd@z Thu Jan 1 00:00:00 1970 From: Catalin Marinas Subject: Re: [PATCH V3] of: Set the DMA mask to 64 bits when dma_addr_t is 64-bits Date: Fri, 26 Apr 2013 21:52:00 +0100 Message-ID: <20130426205159.GA48325@MacBook-Pro.local> References: <1367008266-1431-1-git-send-email-lauraa@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1367008266-1431-1-git-send-email-lauraa@codeaurora.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Laura Abbott Cc: "devicetree-discuss@lists.ozlabs.org" , "linux-arm-kernel@lists.infradead.org" List-Id: devicetree@vger.kernel.org On Fri, Apr 26, 2013 at 09:31:06PM +0100, Laura Abbott wrote: > Currently, of_platform_device_create_pdata always sets the > coherent DMA mask to 32 bits. On ARM systems without CONFIG_ZONE_DMA, > arm_dma_limit gets set to ~0 or 0xFFFFFFFFFFFFFFFF on LPAE based > systems. Since arm_dma_limit represents the smallest dma_mask > on the system, the default of 32 bits prevents any dma_coherent > allocation from succeeding unless clients manually set the > dma mask first. Rather than make every client on an LPAE system set > the mask manually, account for the size of dma_addr_t when setting > the coherent mask. > > Signed-off-by: Laura Abbott Looks good. Acked-by: Catalin Marinas