From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754798AbbLJJ2i (ORCPT ); Thu, 10 Dec 2015 04:28:38 -0500 Received: from mout.kundenserver.de ([212.227.126.133]:62912 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753907AbbLJJ2e (ORCPT ); Thu, 10 Dec 2015 04:28:34 -0500 From: Arnd Bergmann To: linux-arm-kernel@lists.infradead.org Cc: Geert Uytterhoeven , Brian Norris , Boris BREZILLON , Kuninori Morimoto , Linux-sh list , Magnus Damm , "linux-kernel@vger.kernel.org" , Simon Horman , MTD Maling List , Frans Klaver , David Woodhouse Subject: Re: [PATCH] mtd: sh_flctl: pass FIFO as physical address Date: Thu, 10 Dec 2015 10:27:25 +0100 Message-ID: <6087453.7mT0kthNee@wuerfel> User-Agent: KMail/4.11.5 (Linux/3.16.0-10-generic; KDE/4.11.5; x86_64; ; ) In-Reply-To: References: <3152458.D3kElfhRW2@wuerfel> <20151210022146.GH144338@google.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Provags-ID: V03:K0:Ilb3SaKbzwd1D8zhYPTA8w/uGVaWUijtvLrHaEUerpAOP+HZTLe 7tJQAHBVeuy7ZSAJ67camC76mJ9FYgtLUEUFmm9IzXFmtKUKWg5w5ZamxiwLjIE7TNGVb7G ASdy1QJL6AukZBqgVNwQN4nkslA+iIgWzqPaofgEF2ueemtDsdx5jcXiaeT7P3GJPCyrma7 L7l3K2AWk18wkvVmLA85A== X-UI-Out-Filterresults: notjunk:1;V01:K0:tvjeF+RSsN0=:EyO98tQoJHmvAxAnA7q+M8 siYdgKipjyqqTjDnvNhiSfta3BLGp8i+WWSDNDjyLBc4NWI3LDJVCdhDV19YO/bS09ric2GkI boZOtKd/wwVvlsk/aZXnFBwLz3g6/+qOCoqSDBVP+R8OvargsmOrkszIXZV7edM4DNwY16gpR kGQhEsnWY5YXm+iZojTtRlnto6K6jBSA1/Jqjb+u0BhclS43sUzB4G5l+D56FIV0zeYVz9rvK V8To0VkSYy/Jsti8prEaqRBWioBDWPawFXwttZ87/spnRQBOziIV4+uMbJi7BNmIHkCnKp8BN vaX03lrbYETjWym5FcSlOlrPdLj3ft1oHtEZ+9yIsWrgpeV4fxh7XcgzKQuKOuFtDvcOhh2+9 GvSMaXUVN8hny5yVbEkOhuNvXzh9Gq+2OajpALCIUfL3FNyoMgn9gdC64p+Sp1vj9T2z8r2Bf WzQukjtUcHHCnNRa1DOv5SAXtvW2yDp35f0lTorSlpw98vSyb7rH+Sxsa3sWZSoPOZoH6BBH8 KWXVK9MDJye30TDacvrjbwmzr2Ob6+Zj1FAq11Yx6S54Najq7Vl9MTi+Us4GuLneDci8ha5FM qQHwgCxpGrNPjunItUljW3e9vaLKqiXMOXRwayxD0hcRlhfayBzgVRX1eh8BvkvvGePmo5JzD BJNfPZz/6e86jzUCTdEkeREUJfJTn8ExcSGveiqgewMnd7niNhXyWBCbPNYeciFEbZHBkuJfp un+zLJzIkzRNvQMx Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thursday 10 December 2015 10:02:06 Geert Uytterhoeven wrote: > > On Thu, Dec 10, 2015 at 3:21 AM, Brian Norris > wrote: > > On Tue, Dec 08, 2015 at 05:30:02PM +0100, Geert Uytterhoeven wrote: > >> On Tue, Dec 8, 2015 at 4:38 PM, Arnd Bergmann wrote: > >> > By convention, the FIFO address we pass using dmaengine_slave_config > >> > is a physical address in the form that is understood by the DMA > >> > engine, as a dma_addr_t, phys_addr_t or resource_size_t. > >> > > >> > The sh_flctl driver however passes a virtual __iomem address that > >> > gets cast to dma_addr_t in the slave driver. This happens to work > >> > on shmobile because that platform sets up an identity mapping for > >> > its MMIO regions, but such code is not portable to other platforms, > >> > and prevents us from ever changing the platform mapping or reusing > >> > the driver on other architectures like ARM64 that might not have the > >> > mapping. > >> > >> Note that since the removal of (ARM) sh7367/sh7377/sh7372 support, this > >> driver is used on SH only. > > > > It's still available as COMPILE_TEST, so it's still worth fixing. > > > > But really, does anyone use this driver any more? > > It's used on the sh7723-based AP-325RXA board. > No idea if anyone is really using it. If the question is about removing the driver, I think the answer then is that we should either remove the platform and the driver, or neither of them. sh7723 seems to be one of the more recent ones (added in 2009, only 7 of the 40 CPU subtypes are more recent, the last ones were added in 2012). Arnd