compile gcc on odroid-u2 with mfpu=neon – Arch linux

currently gcc 4.8.1 on Arch (07.10.13)

Flags in makepkg.conf

CPPFLAGS=""
CFLAGS="-O3 -pipe -march=armv7-a -mcpu=cortex-a9 -mfloat-abi=hard -mfpu=neon -fstack-protector --param=ssp-buffer-size=4"
CXXFLAGS="-O3 -pipe -march=armv7-a -mcpu=cortex-a9 -mfloat-abi=hard -mfpu=neon -fstack-protector --param=ssp-buffer-size=4"

PKGBUILD needs one patch adding (neon-update3.patch) and one removing (armhf-triplet-trunk.diff)
As it is patch will fail to find the file to be patched and you will have to supply the full path.
in my case

 /var/build/gcc/src/gcc-4.8-20130725/gcc/config/arm/neon.md

Also need to change flags pass to GCC by configure.

[[ $CARCH == "armv7h" ]] && CONFIGFLAG="--host=armv7l-unknown-linux-gnueabihf --build=armv7l-unknown-linux-gnueabihf --with-arch=armv7-a --with-float=hard --with-fpu=neon"

The PKGBUILD with the changes is attached as is neon-update3.patch

The original PKGBUILD is from https://github.com/archlinuxarm/PKGBUILDs/blob/master/core/gcc/PKGBUILD

neon-update3.patch is from http://gcc.1065356.n5.nabble.com/PATCH-ARM-Fix-unrecognizable-vector-comparisons-td947064.html

PKGBUILD.orig

PKGBUILD

neon-update3.patch

Force Mono (Black and White) with LPR

In the below substitute HL4140CN with the printer name. (also the option names may difer, this is for a brother)

List the options with:

lpoptions -p HL4140CN -l

Add an “instance” of the printer with the option for Mono printing

lpoptions -p HL4140CN/bw -o BRMonoColor=Mono

Now the following will print Mono

lpr -P HL4140CN/bw any.txt

Disable Nvidia HDMI sound under Linux

Sound under linux and KDE seems to able to get itself confused with its settings easily enough so their is no point adding to the confusion. I’m sure that HDMI is hugely useful to those that want it and use it but up to now I never have.
Among the issues I’ve noticed is that at seemingly random times the KDE mixer Kmix will revert to setting the Nvidia HDMI output as the master channel. Then I have to change it back which starts to get old fairly rapidly. Continue reading

Postfixadmin on iredmail with mysql backend

iredmail is very useful as even though I have set up mail servers myself I tend to struggle with it and then feel it is probably less than secure / optimal.

iredmail used to come with postfixadmin as an option , then there were some instructions on adding it, but for the last couple of years the instructions no longer work fully. postfixadmin does what I need but the free iredadmin is lacking some needed (by me) features. The pro version is very expensive and has way more features than I need.
Continue reading

Nvidia – Chromium Zombie processes Arch Linux fix

When using the the Nvidia blob the Chromium (and Chrome) browser leaves zombie processes behind causing the system to slow over time. This is apparently caused by nvidia threads forking  when according to POSIX specs they probably shouldn’t, and Chromium’s custom malloc  (tmalloc) not playing nicely with this out of spec behaviour whereas the glib malloc does cope with it !
Continue reading

What this blog is and isn’t

What this blog is

This blog is something I’ve been meaning to do for a very long time.

I’ve been messing around with Linux, servers and websites for years. Some parts come easy, some parts I have trouble with. Some things I (almost) always remember, some things I never do.

So I intend to record ‘snippets’ of information, as and when I come across them, which I believe I may find helpful to myself in the future. So that I don’t have to go google hunting for the same  information every time I encounter the same problem.

If anyone else come across this blog and it helps them all good. But it probably won’t.

What this blog isn’t

A step by step guide on anything.

Guaranteed to be accurate.

Well written.

PS

I sell electronic cigarettes and e-liquid