From mboxrd@z Thu Jan 1 00:00:00 1970 From: Geert Uytterhoeven Date: Thu, 20 Mar 2014 19:04:22 +0000 Subject: Re: DMABOUNCE in pci-rcar Message-Id: List-Id: References: <201402241200.21944.arnd@arndb.de> <20140320173106.GA19395@obsidianresearch.com> <532B2628.5080305@codethink.co.uk> <201403201929.13633.arnd@arndb.de> <20140320183932.GA7528@n2100.arm.linux.org.uk> In-Reply-To: <20140320183932.GA7528@n2100.arm.linux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-arm-kernel@lists.infradead.org Hi Russell, On Thu, Mar 20, 2014 at 7:39 PM, Russell King - ARM Linux wrote: > That all said, what I find most annoying is that Ben has ignored my > question about exactly what the nature of the limitation is on this > platform. My response to that is - if you're not going to do the > curtesy of answering such a simple question, then you don't get to > patch the kernel for this problem. Ben did answer: "If the window is set to 2GiB it can only access 2GiB aligned to 2GiB boundary, however DRAM spans a 2GiB boundary (being at 1-3GiB)" Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759630AbaCTTE0 (ORCPT ); Thu, 20 Mar 2014 15:04:26 -0400 Received: from mail-pb0-f43.google.com ([209.85.160.43]:59910 "EHLO mail-pb0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758670AbaCTTEX (ORCPT ); Thu, 20 Mar 2014 15:04:23 -0400 MIME-Version: 1.0 In-Reply-To: <20140320183932.GA7528@n2100.arm.linux.org.uk> References: <201402241200.21944.arnd@arndb.de> <20140320173106.GA19395@obsidianresearch.com> <532B2628.5080305@codethink.co.uk> <201403201929.13633.arnd@arndb.de> <20140320183932.GA7528@n2100.arm.linux.org.uk> Date: Thu, 20 Mar 2014 20:04:22 +0100 X-Google-Sender-Auth: C3ybQ64I-OhR66iHI02qdQaTX68 Message-ID: Subject: Re: DMABOUNCE in pci-rcar From: Geert Uytterhoeven To: Russell King - ARM Linux Cc: Arnd Bergmann , Ben Dooks , Jason Gunthorpe , Linux-sh list , "linux-pci@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Magnus Damm , Ben Dooks , Bjorn Helgaas , Simon Horman , "linux-arm-kernel@lists.infradead.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Russell, On Thu, Mar 20, 2014 at 7:39 PM, Russell King - ARM Linux wrote: > That all said, what I find most annoying is that Ben has ignored my > question about exactly what the nature of the limitation is on this > platform. My response to that is - if you're not going to do the > curtesy of answering such a simple question, then you don't get to > patch the kernel for this problem. Ben did answer: "If the window is set to 2GiB it can only access 2GiB aligned to 2GiB boundary, however DRAM spans a 2GiB boundary (being at 1-3GiB)" Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pb0-f43.google.com ([209.85.160.43]:59910 "EHLO mail-pb0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758670AbaCTTEX (ORCPT ); Thu, 20 Mar 2014 15:04:23 -0400 MIME-Version: 1.0 In-Reply-To: <20140320183932.GA7528@n2100.arm.linux.org.uk> References: <201402241200.21944.arnd@arndb.de> <20140320173106.GA19395@obsidianresearch.com> <532B2628.5080305@codethink.co.uk> <201403201929.13633.arnd@arndb.de> <20140320183932.GA7528@n2100.arm.linux.org.uk> Date: Thu, 20 Mar 2014 20:04:22 +0100 Message-ID: Subject: Re: DMABOUNCE in pci-rcar From: Geert Uytterhoeven To: Russell King - ARM Linux Cc: Arnd Bergmann , Ben Dooks , Jason Gunthorpe , Linux-sh list , "linux-pci@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Magnus Damm , Ben Dooks , Bjorn Helgaas , Simon Horman , "linux-arm-kernel@lists.infradead.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-pci-owner@vger.kernel.org List-ID: Hi Russell, On Thu, Mar 20, 2014 at 7:39 PM, Russell King - ARM Linux wrote: > That all said, what I find most annoying is that Ben has ignored my > question about exactly what the nature of the limitation is on this > platform. My response to that is - if you're not going to do the > curtesy of answering such a simple question, then you don't get to > patch the kernel for this problem. Ben did answer: "If the window is set to 2GiB it can only access 2GiB aligned to 2GiB boundary, however DRAM spans a 2GiB boundary (being at 1-3GiB)" Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds From mboxrd@z Thu Jan 1 00:00:00 1970 From: geert@linux-m68k.org (Geert Uytterhoeven) Date: Thu, 20 Mar 2014 20:04:22 +0100 Subject: DMABOUNCE in pci-rcar In-Reply-To: <20140320183932.GA7528@n2100.arm.linux.org.uk> References: <201402241200.21944.arnd@arndb.de> <20140320173106.GA19395@obsidianresearch.com> <532B2628.5080305@codethink.co.uk> <201403201929.13633.arnd@arndb.de> <20140320183932.GA7528@n2100.arm.linux.org.uk> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Russell, On Thu, Mar 20, 2014 at 7:39 PM, Russell King - ARM Linux wrote: > That all said, what I find most annoying is that Ben has ignored my > question about exactly what the nature of the limitation is on this > platform. My response to that is - if you're not going to do the > curtesy of answering such a simple question, then you don't get to > patch the kernel for this problem. Ben did answer: "If the window is set to 2GiB it can only access 2GiB aligned to 2GiB boundary, however DRAM spans a 2GiB boundary (being at 1-3GiB)" Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds