Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751404AbdFEPLo (ORCPT ); Mon, 5 Jun 2017 11:11:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:46852 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751182AbdFEPLm (ORCPT ); Mon, 5 Jun 2017 11:11:42 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 88A9E23A06 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=atull@kernel.org MIME-Version: 1.0 In-Reply-To: <684ea151ba9aa2c6555a299daf56552ddc11f596.1496434383.git.stillcompiling@gmail.com> References: <20170525172911.11467-1-stillcompiling@gmail.com> <684ea151ba9aa2c6555a299daf56552ddc11f596.1496434383.git.stillcompiling@gmail.com> From: Alan Tull Date: Mon, 5 Jun 2017 10:11:00 -0500 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v12 1/6] fpga: Add flag to indicate SPI bitstream is bit-reversed To: Joshua Clayton Cc: Moritz Fischer , Anatolij Gustschin , Bastian Stender , Shawn Guo , Rob Herring , Mark Rutland , Sascha Hauer , Fabio Estevam , Russell King , linux-fpga@vger.kernel.org, "devicetree@vger.kernel.org" , linux-kernel , "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 Content-Length: 1883 Lines: 49 On Fri, Jun 2, 2017 at 3:30 PM, Joshua Clayton wrote: > From: Anatolij Gustschin > > Add a flag that is passed to the write_init() callback, > indicating that the SPI bitstream starts with LSB first. > SPI controllers usually send data with MSB first. If an > FPGA expects bitstream data as LSB first, the data must > be reversed either by the SPI controller or by the driver. > > Alternatively the bitstream could be prepared as bit-reversed > to avoid the bit-swapping while sending. This flag indicates > such bit-reversed SPI bitstream. The low-level driver will > deal with the flag and perform bit-reversing if needed. > > Signed-off-by: Anatolij Gustschin > Signed-off-by: Joshua Clayton Signed-off-by: Alan Tull > --- > > Changes from v11 (all in patch 4/4) > - Change "Altera V FPGA" to simply "Altera FPGA" > - Change the devicetree name to a generic "fpga: fpga@0" > from "fpga_spi: cyclonespi@0" > > include/linux/fpga/fpga-mgr.h | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/include/linux/fpga/fpga-mgr.h b/include/linux/fpga/fpga-mgr.h > index b4ac24c4411d..01c348ca38b7 100644 > --- a/include/linux/fpga/fpga-mgr.h > +++ b/include/linux/fpga/fpga-mgr.h > @@ -67,10 +67,12 @@ enum fpga_mgr_states { > * FPGA Manager flags > * FPGA_MGR_PARTIAL_RECONFIG: do partial reconfiguration if supported > * FPGA_MGR_EXTERNAL_CONFIG: FPGA has been configured prior to Linux booting > + * FPGA_MGR_BITSTREAM_LSB_FIRST: SPI bitstream bit order is LSB first > */ > #define FPGA_MGR_PARTIAL_RECONFIG BIT(0) > #define FPGA_MGR_EXTERNAL_CONFIG BIT(1) > #define FPGA_MGR_ENCRYPTED_BITSTREAM BIT(2) > +#define FPGA_MGR_BITSTREAM_LSB_FIRST BIT(3) > > /** > * struct fpga_image_info - information specific to a FPGA image > -- > 2.11.0 >