docs/README-raspberrypi.md
changeset 9025 d09d4b578e77
parent 9023 276802355854
child 9066 c2af3ff967cc
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/docs/README-raspberrypi.md	Tue Jul 29 08:04:15 2014 -0700
     1.3 @@ -0,0 +1,160 @@
     1.4 +Raspberry Pi
     1.5 +================================================================================
     1.6 +
     1.7 +Requirements:
     1.8 +
     1.9 +Raspbian (other Linux distros may work as well).
    1.10 +
    1.11 +================================================================================
    1.12 + Features
    1.13 +================================================================================
    1.14 +
    1.15 +* Works without X11
    1.16 +* Hardware accelerated OpenGL ES 2.x
    1.17 +* Sound via ALSA
    1.18 +* Input (mouse/keyboard/joystick) via EVDEV
    1.19 +* Hotplugging of input devices via UDEV
    1.20 +
    1.21 +================================================================================
    1.22 + Raspbian Build Dependencies
    1.23 +================================================================================
    1.24 +
    1.25 +sudo apt-get install libudev-dev libasound2-dev libdbus-1-dev
    1.26 +
    1.27 +You also need the VideoCore binary stuff that ships in /opt/vc for EGL and 
    1.28 +OpenGL ES 2.x, it usually comes pre installed, but in any case:
    1.29 +    
    1.30 +sudo apt-get install libraspberrypi0 libraspberrypi-bin libraspberrypi-dev
    1.31 +
    1.32 +================================================================================
    1.33 + Cross compiling from x86 Linux
    1.34 +================================================================================
    1.35 +
    1.36 +To cross compile SDL for Raspbian from your desktop machine, you'll need a
    1.37 +Raspbian system root and the cross compilation tools. We'll assume these tools
    1.38 +will be placed in /opt/rpi-tools
    1.39 +
    1.40 +    sudo git clone --depth 1 https://github.com/raspberrypi/tools /opt/rpi-tools
    1.41 +
    1.42 +You'll also need a Rasbian binary image.
    1.43 +Get it from: http://downloads.raspberrypi.org/raspbian_latest 
    1.44 +After unzipping, you'll get file with a name like: <date>-wheezy-raspbian.img
    1.45 +Let's assume the sysroot will be built in /opt/rpi-sysroot.
    1.46 +
    1.47 +    export SYSROOT=/opt/rpi-sysroot
    1.48 +    sudo kpartx -a -v <path_to_raspbian_image>.img
    1.49 +    sudo mount -o loop /dev/mapper/loop0p2 /mnt
    1.50 +    sudo cp -r /mnt $SYSROOT
    1.51 +    sudo apt-get install qemu binfmt-support qemu-user-static
    1.52 +    sudo cp /usr/bin/qemu-arm-static $SYSROOT/usr/bin
    1.53 +    sudo mount --bind /dev $SYSROOT/dev
    1.54 +    sudo mount --bind /proc $SYSROOT/proc
    1.55 +    sudo mount --bind /sys $SYSROOT/sys
    1.56 +
    1.57 +Now, before chrooting into the ARM sysroot, you'll need to apply a workaround,
    1.58 +edit $SYSROOT/etc/ld.so.preload and comment out all lines in it.
    1.59 +
    1.60 +    sudo chroot $SYSROOT
    1.61 +    apt-get install libudev-dev libasound2-dev libdbus-1-dev libraspberrypi0 libraspberrypi-bin libraspberrypi-dev libx11-dev libxext-dev libxrandr-dev libxcursor-dev libxi-dev libxinerama-dev libxxf86vm-dev libxss-dev
    1.62 +    exit
    1.63 +    sudo umount $SYSROOT/dev
    1.64 +    sudo umount $SYSROOT/proc
    1.65 +    sudo umount $SYSROOT/sys
    1.66 +    sudo umount /mnt
    1.67 +    
    1.68 +There's one more fix required, as the libdl.so symlink uses an absolute path 
    1.69 +which doesn't quite work in our setup.
    1.70 +
    1.71 +    sudo rm -rf $SYSROOT/usr/lib/arm-linux-gnueabihf/libdl.so
    1.72 +    sudo ln -s ../../../lib/arm-linux-gnueabihf/libdl.so.2 $SYSROOT/usr/lib/arm-linux-gnueabihf/libdl.so
    1.73 +
    1.74 +The final step is compiling SDL itself.
    1.75 +
    1.76 +    export CC="/opt/rpi-tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/bin/arm-linux-gnueabihf-gcc --sysroot=$SYSROOT -I$SYSROOT/opt/vc/include -I$SYSROOT/usr/include -I$SYSROOT/opt/vc/include/interface/vcos/pthreads -I$SYSROOT/opt/vc/include/interface/vmcs_host/linux"
    1.77 +    cd <SDL SOURCE>
    1.78 +    mkdir -p build;cd build
    1.79 +    ../configure --with-sysroot=$SYSROOT --host=arm-raspberry-linux-gnueabihf --prefix=$PWD/rpi-sdl2-installed --disable-pulseaudio --disable-esd
    1.80 +    make
    1.81 +    make install
    1.82 +
    1.83 +To be able to deploy this to /usr/local in the Raspbian system you need to fix up a few paths:
    1.84 +    
    1.85 +    perl -w -pi -e "s#$PWD/rpi-sdl2-installed#/usr/local#g;" ./rpi-sdl2-installed/lib/libSDL2.la ./rpi-sdl2-installed/lib/pkgconfig/sdl2.pc ./rpi-sdl2-installed/bin/sdl2-config
    1.86 +    
    1.87 +================================================================================
    1.88 + Apps don't work or poor video/audio performance
    1.89 +================================================================================
    1.90 +
    1.91 +If you get sound problems, buffer underruns, etc, run "sudo rpi-update" to 
    1.92 +update the RPi's firmware. Note that doing so will fix these problems, but it
    1.93 +will also render the CMA - Dynamic Memory Split functionality useless.
    1.94 +
    1.95 +Also, by default the Raspbian distro configures the GPU RAM at 64MB, this is too
    1.96 +low in general, specially if a 1080p TV is hooked up.
    1.97 +
    1.98 +See here how to configure this setting: http://elinux.org/RPiconfig
    1.99 +
   1.100 +Using a fixed gpu_mem=128 is the best option (specially if you updated the 
   1.101 +firmware, using CMA probably won't work, at least it's the current case).
   1.102 +
   1.103 +================================================================================
   1.104 + No input
   1.105 +================================================================================
   1.106 +
   1.107 +Make sure you belong to the "input" group.
   1.108 +
   1.109 +    sudo usermod -aG input `whoami`
   1.110 +
   1.111 +================================================================================
   1.112 + No HDMI Audio
   1.113 +================================================================================
   1.114 +
   1.115 +If you notice that ALSA works but there's no audio over HDMI, try adding:
   1.116 +    
   1.117 +    hdmi_drive=2
   1.118 +    
   1.119 +to your config.txt file and reboot.
   1.120 +
   1.121 +Reference: http://www.raspberrypi.org/phpBB3/viewtopic.php?t=5062
   1.122 +
   1.123 +================================================================================
   1.124 + Text Input API support
   1.125 +================================================================================
   1.126 +
   1.127 +The Text Input API is supported, with translation of scan codes done via the
   1.128 +kernel symbol tables. For this to work, SDL needs access to a valid console.
   1.129 +If you notice there's no SDL_TEXTINPUT message being emitted, double check that
   1.130 +your app has read access to one of the following:
   1.131 +    
   1.132 +* /proc/self/fd/0
   1.133 +* /dev/tty
   1.134 +* /dev/tty[0...6]
   1.135 +* /dev/vc/0
   1.136 +* /dev/console
   1.137 +
   1.138 +This is usually not a problem if you run from the physical terminal (as opposed
   1.139 +to running from a pseudo terminal, such as via SSH). If running from a PTS, a 
   1.140 +quick workaround is to run your app as root or add yourself to the tty group,
   1.141 +then re login to the system.
   1.142 +
   1.143 +   sudo usermod -aG tty `whoami`
   1.144 +    
   1.145 +The keyboard layout used by SDL is the same as the one the kernel uses.
   1.146 +To configure the layout on Raspbian:
   1.147 +    
   1.148 +    sudo dpkg-reconfigure keyboard-configuration
   1.149 +    
   1.150 +To configure the locale, which controls which keys are interpreted as letters,
   1.151 +this determining the CAPS LOCK behavior:
   1.152 +
   1.153 +    sudo dpkg-reconfigure locales
   1.154 +
   1.155 +================================================================================
   1.156 + Notes
   1.157 +================================================================================
   1.158 +
   1.159 +* When launching apps remotely (via SSH), SDL can prevent local keystrokes from
   1.160 +  leaking into the console only if it has root privileges. Launching apps locally
   1.161 +  does not suffer from this issue.
   1.162 +  
   1.163 +