From mboxrd@z Thu Jan 1 00:00:00 1970 From: joerg.krause@embedded.rocks (=?ISO-8859-1?Q?J=F6rg?= Krause) Date: Wed, 02 Nov 2016 09:30:18 +0100 Subject: Low network throughput on i.MX28 In-Reply-To: References: <1476313753.2065.11.camel@embedded.rocks> <20161013084807.6a231fdb@ipc1.ka-ro> <20161014081349.1afb22c6@ipc1.ka-ro> <1476521171.1670.2.camel@embedded.rocks> <2131339088.8778.d47a56f6-921e-4d6c-9a5c-2e77bfd5d281.open-xchange@email.1und1.de> <8C3BD5BA-252F-4A95-B938-50356A23974E@embedded.rocks> <2003579366.391192.0cc5acd0-af27-4ef7-892f-3c2dd86176ba.open-xchange@email.1und1.de> <1477696028.31471.3.camel@embedded.rocks> <1143135945.89173.6f7a3a9a-5120-4cc2-a76b-92a516ab6500.open-xchange@email.1und1.de> <1478074489.19127.7.camel@embedded.rocks> Message-ID: <1478075418.19127.9.camel@embedded.rocks> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wed, 2016-11-02 at 09:24 +0100, Stefan Wahren wrote: > Am 02.11.2016 um 09:14 schrieb J?rg Krause: > > On Sat, 2016-10-29 at 11:08 +0200, Stefan Wahren wrote: > > > > J?rg Krause hat am 29. Oktober > > > > 2016 > > > > um 01:07 > > > > geschrieben: > > > > > > > > > > > > You mentioned [1] an optimization in the Freescale vendor Linux > > > > kernel > > > > [2]. I would really like to see this optimization in the > > > > mainline > > > > kernel. > > > > > > > > Did you ever tried to port this code from Freescale to > > > > mainline? > > > > > > Yes, i tried once but i was frustrated soon because of the lot of > > > required > > > changes and resulting issues. > > > > I got the PIO mode working for the mxs-mmc driver. For this I > > ported > > the PIO code from the vendor kernel and removed the usage of the > > DMA > > engine entirely. > > Good job Thanks! > > > > Testing network bandwidth with iperf, I get about ~10Mbit/sec with > > PIO > > mode compared to ~6.5Mbit/sec with DMA mode for UDP and about > > ~6.5Mbit/sec compared to ~4.5Mbit/sec with DMA mode for TCP. > > And how about MMC / sd card performance? Can't tell as my custom i.MX28 board does not have a SD card interface. I will share the code after doing some cleanups and further tests so you might test it as well. J?rg