From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?iso-8859-1?Q?M=E5ns_Rullg=E5rd?= Subject: Re: [PATCH 03/15] dmaengine: dw: rename masters to reflect actual topology Date: Sun, 24 Jan 2016 20:19:46 +0000 Message-ID: References: <1453663322-14474-1-git-send-email-mans@mansr.com> <1453663322-14474-4-git-send-email-mans@mansr.com> <20160124200959.GA15633@samfundet.no> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20160124200959.GA15633-BrfabpQBY5qlHtIdYg32fQ@public.gmane.org> (Hans-Christian Noren Egtvedt's message of "Sun, 24 Jan 2016 21:09:59 +0100") Sender: linux-spi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Hans-Christian Noren Egtvedt Cc: Viresh Kumar , Andy Shevchenko , Vinod Koul , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, dmaengine-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Haavard Skinnemoen , Tejun Heo , Dan Williams , Daniel Mack , Haojian Zhuang , Robert Jarzmik , Mark Brown , Greg Kroah-Hartman , Jiri Slaby , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-ide-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-serial-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: devicetree@vger.kernel.org Hans-Christian Noren Egtvedt writes: > Around Sun 24 Jan 2016 19:21:50 +0000 or thereabout, Mans Rullgard wr= ote: >> From: Andy Shevchenko >>=20 >> The source and destination masters are reflecting buses or their lay= ers to >> where the different devices can be connected. The patch changes the = master >> names to reflect which one is related to which independently on the = transfer >> direction. >>=20 >> The outcome of the change is that the memory data width is now alway= s limited >> by a data width of the master which is dedicated to communicate to m= emory. >>=20 >> The patch will not break anything since all current users have the s= ame data >> width for all masters. Though it would be nice to revisit avr32 plaf= orms to >> check what is the actual hardware topology is used there. It seems t= hat it has >> one bus and two masters on it as stated by Table 8-2, that's why eve= rything >> works independently on the master in use. The purpose of the sequent= ial patch >> is to fix the driver for configuration of more that one bus. > > Not entirely sure what you want to have confirmed here. There are mul= tiple > masters and slaves on the HMATRIX internal bus on AVR32, and the DMA > controller supports up to three simultaneous configurations. > > Sounds good to support configuration of more than one bus. I thought = we > always did support that? Perhaps it was a non-standard avr32 implemen= tation. The DW DMA controller on the AT32AP7000 serves the MCI, AC97, and ABDAC peripherals. It appears to work regardless of the values put in the various master select fields. Perhaps the topology is hardwired in the DMA controller and those fields are ignored. The AVR32 works both before and after this patch series, the main purpose of which (at least my patches) is to fix the SATA driver on 460EX. >> The change is done in the assumption that src_master and dst_master = are >> reflecting a connection to the memory and peripheral correspondently= on all >> platforms except 460ex. >>=20 >> Signed-off-by: Andy Shevchenko >> Signed-off-by: Mans Rullgard > > For the avr32 related stuff: > > Acked-by: Hans-Christian Egtvedt > >> --- >> Documentation/devicetree/bindings/dma/snps-dma.txt | 4 ++-- >> arch/avr32/mach-at32ap/at32ap700x.c | 16 ++++++++---= ----- >> drivers/ata/sata_dwc_460ex.c | 4 ++-- >> drivers/dma/dw/core.c | 15 +++++++----= ---- >> drivers/dma/dw/platform.c | 12 ++++++-----= - >> drivers/dma/dw/regs.h | 4 ++-- >> drivers/spi/spi-pxa2xx-pci.c | 8 ++++---- >> drivers/tty/serial/8250/8250_pci.c | 8 ++++---- >> include/linux/platform_data/dma-dw.h | 8 ++++---- >> 9 files changed, 39 insertions(+), 40 deletions(-) > > > > --=20 > Best regards, Hans-Christian Egtvedt --=20 M=E5ns Rullg=E5rd -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html