From 8222bfe56d4dabe8d92fc4b25ea1b0163b16f3e1 Mon Sep 17 00:00:00 2001 From: 3gg <3gg@shellblade.net> Date: Sat, 4 May 2024 16:51:29 -0700 Subject: Initial commit. --- src/contrib/SDL-2.30.2/docs/README-raspberrypi.md | 180 ++++++++++++++++++++++ 1 file changed, 180 insertions(+) create mode 100644 src/contrib/SDL-2.30.2/docs/README-raspberrypi.md (limited to 'src/contrib/SDL-2.30.2/docs/README-raspberrypi.md') diff --git a/src/contrib/SDL-2.30.2/docs/README-raspberrypi.md b/src/contrib/SDL-2.30.2/docs/README-raspberrypi.md new file mode 100644 index 0000000..7f9bfb1 --- /dev/null +++ b/src/contrib/SDL-2.30.2/docs/README-raspberrypi.md @@ -0,0 +1,180 @@ +Raspberry Pi +============ + +Requirements: + +Raspbian (other Linux distros may work as well). + +Features +-------- + +* Works without X11 +* Hardware accelerated OpenGL ES 2.x +* Sound via ALSA +* Input (mouse/keyboard/joystick) via EVDEV +* Hotplugging of input devices via UDEV + + +Raspbian Build Dependencies +--------------------------- + +sudo apt-get install libudev-dev libasound2-dev libdbus-1-dev + +You also need the VideoCore binary stuff that ships in /opt/vc for EGL and +OpenGL ES 2.x, it usually comes pre-installed, but in any case: + +sudo apt-get install libraspberrypi0 libraspberrypi-bin libraspberrypi-dev + + +NEON +---- + +If your Pi has NEON support, make sure you add -mfpu=neon to your CFLAGS so +that SDL will select some otherwise-disabled highly-optimized code. The +original Pi units don't have NEON, the Pi2 probably does, and the Pi3 +definitely does. + + +Cross compiling from x86 Linux +------------------------------ + +To cross compile SDL for Raspbian from your desktop machine, you'll need a +Raspbian system root and the cross compilation tools. We'll assume these tools +will be placed in /opt/rpi-tools + + sudo git clone --depth 1 https://github.com/raspberrypi/tools /opt/rpi-tools + +You'll also need a Raspbian binary image. +Get it from: http://downloads.raspberrypi.org/raspbian_latest +After unzipping, you'll get file with a name like: "-wheezy-raspbian.img" +Let's assume the sysroot will be built in /opt/rpi-sysroot. + + export SYSROOT=/opt/rpi-sysroot + sudo kpartx -a -v .img + sudo mount -o loop /dev/mapper/loop0p2 /mnt + sudo cp -r /mnt $SYSROOT + sudo apt-get install qemu binfmt-support qemu-user-static + sudo cp /usr/bin/qemu-arm-static $SYSROOT/usr/bin + sudo mount --bind /dev $SYSROOT/dev + sudo mount --bind /proc $SYSROOT/proc + sudo mount --bind /sys $SYSROOT/sys + +Now, before chrooting into the ARM sysroot, you'll need to apply a workaround, +edit $SYSROOT/etc/ld.so.preload and comment out all lines in it. + + sudo chroot $SYSROOT + 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 libxss-dev + exit + sudo umount $SYSROOT/dev + sudo umount $SYSROOT/proc + sudo umount $SYSROOT/sys + sudo umount /mnt + +There's one more fix required, as the libdl.so symlink uses an absolute path +which doesn't quite work in our setup. + + sudo rm -rf $SYSROOT/usr/lib/arm-linux-gnueabihf/libdl.so + sudo ln -s ../../../lib/arm-linux-gnueabihf/libdl.so.2 $SYSROOT/usr/lib/arm-linux-gnueabihf/libdl.so + +The final step is compiling SDL itself. + + export CC="/opt/rpi-tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/bin/arm-linux-gnueabihf-gcc --sysroot=$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" + cd + mkdir -p build;cd build + LDFLAGS="-L$SYSROOT/opt/vc/lib" ../configure --with-sysroot=$SYSROOT --host=arm-raspberry-linux-gnueabihf --prefix=$PWD/rpi-sdl2-installed --disable-pulseaudio --disable-esd + make + make install + +To be able to deploy this to /usr/local in the Raspbian system you need to fix up a few paths: + + perl -w -pi -e "s#$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 + +Apps don't work or poor video/audio performance +----------------------------------------------- + +If you get sound problems, buffer underruns, etc, run "sudo rpi-update" to +update the RPi's firmware. Note that doing so will fix these problems, but it +will also render the CMA - Dynamic Memory Split functionality useless. + +Also, by default the Raspbian distro configures the GPU RAM at 64MB, this is too +low in general, specially if a 1080p TV is hooked up. + +See here how to configure this setting: http://elinux.org/RPiconfig + +Using a fixed gpu_mem=128 is the best option (specially if you updated the +firmware, using CMA probably won't work, at least it's the current case). + +No input +-------- + +Make sure you belong to the "input" group. + + sudo usermod -aG input `whoami` + +No HDMI Audio +------------- + +If you notice that ALSA works but there's no audio over HDMI, try adding: + + hdmi_drive=2 + +to your config.txt file and reboot. + +Reference: http://www.raspberrypi.org/phpBB3/viewtopic.php?t=5062 + +Text Input API support +---------------------- + +The Text Input API is supported, with translation of scan codes done via the +kernel symbol tables. For this to work, SDL needs access to a valid console. +If you notice there's no SDL_TEXTINPUT message being emitted, double check that +your app has read access to one of the following: + +* /proc/self/fd/0 +* /dev/tty +* /dev/tty[0...6] +* /dev/vc/0 +* /dev/console + +This is usually not a problem if you run from the physical terminal (as opposed +to running from a pseudo terminal, such as via SSH). If running from a PTS, a +quick workaround is to run your app as root or add yourself to the tty group, +then re-login to the system. + + sudo usermod -aG tty `whoami` + +The keyboard layout used by SDL is the same as the one the kernel uses. +To configure the layout on Raspbian: + + sudo dpkg-reconfigure keyboard-configuration + +To configure the locale, which controls which keys are interpreted as letters, +this determining the CAPS LOCK behavior: + + sudo dpkg-reconfigure locales + + +OpenGL problems +--------------- + +If you have desktop OpenGL headers installed at build time in your RPi or cross +compilation environment, support for it will be built in. However, the chipset +does not actually have support for it, which causes issues in certain SDL apps +since the presence of OpenGL support supersedes the ES/ES2 variants. +The workaround is to disable OpenGL at configuration time: + + ./configure --disable-video-opengl + +Or if the application uses the Render functions, you can use the SDL_RENDER_DRIVER +environment variable: + + export SDL_RENDER_DRIVER=opengles2 + +Notes +----- + +* When launching apps remotely (via SSH), SDL can prevent local keystrokes from + leaking into the console only if it has root privileges. Launching apps locally + does not suffer from this issue. + + -- cgit v1.2.3