From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Shevchenko Subject: Re: [PATCH v5 00/11] serial: 8250: split LPSS to 8250_lpss, enable DMA on Quark Date: Tue, 24 May 2016 20:37:28 +0300 Message-ID: <1464111448.31269.67.camel@linux.intel.com> References: <1462547840-14091-1-git-send-email-andriy.shevchenko@linux.intel.com> <1463065601.17131.319.camel@linux.intel.com> <1463620733.4224.75.camel@nexus-software.ie> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1463620733.4224.75.camel@nexus-software.ie> Sender: linux-kernel-owner@vger.kernel.org To: Bryan O'Donoghue , Peter Hurley , linux-serial@vger.kernel.org, Vinod Koul , linux-kernel@vger.kernel.org, dmaengine@vger.kernel.org, Greg Kroah-Hartman , ismo.puustinen@intel.com, Heikki Krogerus List-Id: linux-serial@vger.kernel.org On Thu, 2016-05-19 at 02:18 +0100, Bryan O'Donoghue wrote: > On Thu, 2016-05-12 at 18:06 +0300, Andy Shevchenko wrote: > > On Fri, 2016-05-06 at 18:17 +0300, Andy Shevchenko wrote: > > > This is combined series of two things: > > > - split out the Intel LPSS specific driver from 8250_pci into > > > 8250_lpss > > > - enable DMA support on Intel Quark UART > > >=20 > > > The patch has been tested on few Intel SoCs / platforms. In any > > > case I > > > would > > > like to ask Bryan to do independent test. >=20 > Andy. >=20 > It looks as though there's a performance drop when enabling the DMA > here (v) stock PIO mode with the 8250 driver. Below results doesn't show DMA case (by the way, how did you disable DM= A in 3.8.7?) for stock kernel. Anyway, I added preliminary support to change DMA mode run-time. Check my today topic/dw/qrk branch. It would be nice to see all 4 cases: DMA vs non-DMA on stock kernel (Yocto) and mine. P.S. What is the point to test arbitrary tip branch? >=20 > Test setup Galileo Gen1 transmitter - Galileo Gen2 receiver. TX/RX > cross-wired between the Arduino UART headers respectively (pins 0 & 1 > on the "Digital PWM" header), GND pin14 similarly cross-wired. >=20 > User-space: > =C2=A0=C2=A0=C2=A0=C2=A0Receiver: Stock on-flash yocto-tiny kernel 3.= 8.7 > =C2=A0=C2=A0=C2=A0=C2=A0Transmitter: Galileo Debian image : > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0https://sourceforge.net/projects/galil= eodebian/ > =C2=A0=C2=A0=C2=A0=C2=A03.8.7 kernel: On SPI-flash BSP kernel > =C2=A0=C2=A0=C2=A0=C2=A0andy-v4: From your tree > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0d13ffcf ('serial: 8250: attempt to keep Kconfig and > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0Ma= kefile in order') > =C2=A0=C2=A0=C2=A0=C2=A0tip-of-tree : 97f0090 ('Merge tag 'rproc-v4.7= ' of > =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0git://github.com/andersson/remoteproc') >=20 > Results: >=20 > ### Test0 ### >=20 > galileo dma andy-v4 9600 8n1=C2=A0 >=20 > root@galileo:~# time echo "abcdefghijklmnopqrstuvwxyz0123456789" > > /dev/ttyS0 >=20 > real=C2=A0=C2=A0=C2=A0=C2=A00m0.060s > user=C2=A0=C2=A0=C2=A0=C2=A00m0.000s > sys=C2=A0=C2=A0=C2=A0=C2=A0=C2=A00m0.000s >=20 >=20 > galileo non-dma Linux 3.8.7 9600 8n1: >=20 > 9600 8n1 > root@galileo:~# time echo "abcdefghijklmnopqrstuvwxyz0123456789" > > /dev/ttyS0 >=20 > real=C2=A0=C2=A0=C2=A0=C2=A00m0.051s > user=C2=A0=C2=A0=C2=A0=C2=A00m0.000s > sys=C2=A0=C2=A0=C2=A0=C2=A0=C2=A00m0.000s >=20 > galileo non-dma tip-of-tree 9600 8n1: >=20 > root@galileo:~# time echo "abcdefghijklmnopqrstuvwxyz0123456789" > > /dev/ttyS0 >=20 > real=C2=A0=C2=A0=C2=A0=C2=A00m0.048s > user=C2=A0=C2=A0=C2=A0=C2=A00m0.000s > sys=C2=A0=C2=A0=C2=A0=C2=A0=C2=A00m0.000s >=20 >=20 > ### Test1 ### >=20 > galileo dma andy-v4 9600 8n1: >=20 > root@galileo:~# time echo > "abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz012345= 6 > 7 > 89abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz01234= 5 > 6 > 789abcdefghijklmnopqrstuvwxyz0123456789" > /dev/ttyS0 >=20 > real=C2=A0=C2=A0=C2=A0=C2=A00m0.209s > user=C2=A0=C2=A0=C2=A0=C2=A00m0.000s > sys=C2=A0=C2=A0=C2=A0=C2=A0=C2=A00m0.000s >=20 > galileo non-dma Linux 3.8.7 9600 8n1: >=20 > root@galileo:~# time echo > "abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz012345= 6 > 7 > 89abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz01234= 5 > 6 > 789abcdefghijklmnopqrstuvwxyz0123456789" > /dev/ttyS0 >=20 > real=C2=A0=C2=A0=C2=A0=C2=A00m0.206s > user=C2=A0=C2=A0=C2=A0=C2=A00m0.000s > sys=C2=A0=C2=A0=C2=A0=C2=A0=C2=A00m0.000s >=20 >=20 > galileo non-dma tip-of-tree 9600 8n1: >=20 > root@galileo:~# time echo > "abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz012345= 6 > 7 > 89abcdefghijklmnopqrstuvwxyz0123456789abcdefghijklmnopqrstuvwxyz01234= 5 > 6 > 789abcdefghijklmnopqrstuvwxyz0123456789" > /dev/ttyS0 >=20 > real=C2=A0=C2=A0=C2=A0=C2=A00m0.199s > user=C2=A0=C2=A0=C2=A0=C2=A00m0.010s > sys=C2=A0=C2=A0=C2=A0=C2=A0=C2=A00m0.000s >=20 >=20 > --- > bod --=20 Andy Shevchenko Intel Finland Oy