Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752718Ab2H0HIX (ORCPT ); Mon, 27 Aug 2012 03:08:23 -0400 Received: from cassarossa.samfundet.no ([129.241.93.19]:35834 "EHLO cassarossa.samfundet.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752336Ab2H0HIW (ORCPT ); Mon, 27 Aug 2012 03:08:22 -0400 Date: Mon, 27 Aug 2012 09:08:18 +0200 From: Hans-Christian Egtvedt To: Hein Tibosch Cc: Andrew Morton , Linux Kernel Mailing List , Nicolas Ferre , "ludovic.desroches" , Havard Skinnemoen , "linux-mmc@vger.kernel.org" , Chris Ball Subject: Re: [PATCH] avr32-linux: at32ap700x: set DMA slave properties for MCI dw_dmac Message-ID: <20120827070818.GD28721@samfundet.no> References: <503A8D97.4070403@yahoo.es> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <503A8D97.4070403@yahoo.es> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2378 Lines: 67 Around Mon 27 Aug 2012 04:56:55 +0800 or thereabout, Hein Tibosch wrote: PS: I prefer avr32: prefix in the Subject for AVR32 kernel stuff, we already know this is for the Linux kernel ;) > @Andrew: could you please push the patch below? Hans-Christian > doesn't have a GIT tree on kernel.org > > Thanks, Hein > > The MCI makes use of the dw_dmac driver when DMA is being used. > Due to recent changes the driver was broken because: > - the SMS field in the CTLL register received the wrong value 0 > - a patch in dw_dmac allowed for 64-bit transfers on the > memory side, giving an illegal value of 3 in the SRC/DST_TR_WIDTH > register. > This patch sets the SMS to 1 and limits the maximum transfer > width to 2 (32 bits) > > Note: this can only be applied after my patch: > [PATCH 2/2] dw_dmac: max_mem_width limits value for > SRC/DST_TR_WID register Thanks for going through this and fixing the MCI/DMA-combo on AVR32. > Signed-off-by: Hein Tibosch > --- > arch/avr32/mach-at32ap/at32ap700x.c | 4 ++++ > 1 files changed, 4 insertions(+), 0 deletions(-) > diff --git a/arch/avr32/mach-at32ap/at32ap700x.c b/arch/avr32/mach-at32ap/at32ap700x.c > index 0445c4f..e7202af 100644 > --- a/arch/avr32/mach-at32ap/at32ap700x.c > +++ b/arch/avr32/mach-at32ap/at32ap700x.c > @@ -1355,6 +1355,10 @@ at32_add_device_mci(unsigned int id, struct mci_platform_data *data) > | DWC_CFGH_DST_PER(1)); > slave->sdata.cfg_lo &= ~(DWC_CFGL_HS_DST_POL > | DWC_CFGL_HS_SRC_POL); > + /* Give CTLL SMS value 1 */ This comment gives me no information, I don't know what CTLL and SMS are, and what does the magic value 1 do? Either skip the comment, or give a short block here describing why src_master must be one, and max_mem_width must be 2. > + slave->sdata.src_master = 1; > + /* SRC/DST_TR_WIDTH register only accepts 0,1,2 */ > + slave->sdata.max_mem_width = 2; Something like: /* * Setup DMA controller to let source be master, and transfer width to * 32-bit. */ slave->sdata.src_master = 1; slave->sdata.max_mem_width = 2; > > data->dma_slave = slave; > -- mvh Hans-Christian Egtvedt -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/