--- wikisrc/ports/evbarm/raspberry_pi.mdwn 2018/11/06 18:16:43 1.100 +++ wikisrc/ports/evbarm/raspberry_pi.mdwn 2020/10/16 17:44:01 1.140 @@ -1,8 +1,12 @@ [[!meta title="NetBSD/evbarm on Raspberry Pi"]] -This page attempts to document and coordinate efforts towards NetBSD/evbarm on [Raspberry Pi](http://www.raspberrypi.org). All board variants are supported. +This page describes the NetBSD/evbarm port on [Raspberry Pi](http://www.raspberrypi.org) hardware. All [board variants](https://en.wikipedia.org/wiki/Raspberry_Pi#Specifications) earlier than the RPI4 are believed supported, and specific boards known to work are listed. We use e.g. "RPI2" to refer to "Raspberry Pi 2" to save precious bytes on this page. This web page is still 32-bit (aarch32) centric, even though as of mid-2020 aarch64 is also a normal approach. -Initial, limited, Raspberry Pi support was introduced in NetBSD 6.0. NetBSD 7.0 adds complete support for the board, along with introducing support for the quad-core Raspberry Pi 2 board. Raspberry Pi 3 support was added for NetBSD 8, and backported to NetBSD 7 in July of 2017. (This page assumes those using NetBSD 7 are using 7.2, or the netbsd-7 branch after mid 2018.) +Initial, limited, Raspberry Pi support was introduced in NetBSD 6.0. NetBSD 7.0 added complete support for the board, along with introducing support for the quad-core Raspberry Pi 2 board. Raspberry Pi 3 support was added for NetBSD 8. NetBSD 9 supports aarch64, meaning using the newer processors in 64-bit mode (via -current in mid 2018). + +Overall, this page takes the view that NetBSD 7 and earlier are obsolete; aside from history, it is written as if those versions don't exist. + +The HOWTO is written for what works on formal releases, release branches (e.g. netbsd-9) and NetBSD-current. It purposefully does not contain instructions about how to get things to work by installing code that is still being tested and not yet in -current. [[images/raspberrypi.jpg]] @@ -12,12 +16,13 @@ Initial, limited, Raspberry Pi support w # What works (and what doesn't yet) -\todo Add information on Pi Zero and Pi Zero W. +"Works" is primarily relative to the earmv6hf-el and earmv7hf-el CPU targets (32-bit). -## NetBSD 7 and NetBSD 8 +## NetBSD 8 - - RaspberryPi 1, 2, 3 (except Pi 3 builtin WiFi and bluetooth) - - multiple processors on 2/3 + - RPI1, RPI2, RPI2-1.2, RPI3, RPI3+ (except RPI3 builtin WiFi and bluetooth) + - RPI0 and RPI0W are expected to work (without WiFi, and one needs fdt files \todo where from?) + - multiple processors on RPI2/RPI3 - boots normally to multiuser, with FAT32 boot partition on uSD - root filesystem can be uSD or USB-attached mass storage - serial or graphics console (with EDID query / parsing) @@ -32,31 +37,51 @@ Initial, limited, Raspberry Pi support w - I²C: works, could use enhancements, man page - SPI: could use enhancements, man page +## NetBSD 9 + + - aarch64 support (RPI3, and should work on all supported systems with 64-bit CPUs) + - RPI3 new SD host controller driver + ## NetBSD current - - Raspberry Pi 3 builtin bluetooth - - Raspberry Pi 3 new SD host controller driver + - RPI3 builtin bluetooth + +## (maybe) NetBSD current, with manual steps + + These items do not work in the sense that they simply function after a standard install. Being listed here implies only that there has been list traffic that implies that after taking a bunch of steps (e.g. new firmware, new dtbs, enabling drivers, applying patches), one can end up with the feature working. The HOWTO explicitly refrains from describing these steps because they are ephemeral. However, the fact that list traffic indicates success is possible is a clue that proper support is on the horizon, and that is notable. + + - RPI3 and RPI0W builtin WiFi + - RPI4 + +## What needs documenting if it works + + - (Everything listed in the previous section.) + - CM1 + - CM3 + - CM3lite ## What needs work - USB (host); isochronous transfers. - - Raspberry Pi 3 builtin WiFi + - RPI0W Bluetooth Low Energy (probably) # CPU types - - Raspberry Pi 1 uses "earmv6hf". - - Raspberry Pi Zero uses "\todo". - - Raspberry Pi 2 uses "earmv7hf". - - Raspberry Pi 3 uses "earmv7hf". - - Raspberry Pi Zero W uses "\todo". + - RPI1 uses "earmv6hf". + - RPI0 uses "earmv6hf". + - RPI0W uses "earmv6hf". + - RPI2 uses "earmv7hf". + - RPI2-1.2 uses "earmv7hf" or "aarch64" (armv8 CPU hardware) + - RPI3 uses "earmv7hf" or "aarch64" (armv8 CPU hardware) + - RPI4 \todo -Note that one can run earmv6hf userland code on the 2 and 3. In theory the code compiled for earmv7hf will be faster. \todo Benchmark and explain. \todo Explain if one can run the earmv6hf RPI2 kernel on RPI1. \todo Explain if the earmv6hf rpi.img.gz will run on a RPI2/3. +Note that one can run a build of earmv6hf on the 2 and 3. There will still be a kernel7, built to use the 2/3 hardware, but with the armv6 instruction set. -\todo Explain if one can run "eb" variants. (However, using eb is likely to find more bugs because almost everyone uses el. That can either be a reason to run it or not run it.) +In theory the code compiled for earmv7hf will be faster, but anecdotal experience is that it doesn't matter that much. \todo Post a link to a quality benchmark. -\todo Explain if systems built with earm or earmv5 will work on RPI or RPI2/3. +While the evbarm port has "eb" variants (for big-endian mode), the RPI systems do not support eb and these variants will not work. Systems built for older CPU architectures (earm, earmv4, earmv5) are not expected to work on RPI. -See also [[NetBSD/aarch64|aarch64]] for running the Pi 2/3 in 64-bit mode. +The RPI2-1.2, RPI3 and RPI4 have an armv8 CPU that supports aarch64 (64-bit mode) in addition to aarch32 (regular 32-bit ARM). This is supported, from 9 onwards, by the "aarch64" MACHINE_ARCH of evbarm, also available in build.sh via the alias evbarm64. This is also referred to as [[NetBSD/aarch64|aarch64]]. # Installation @@ -65,13 +90,13 @@ See also [[NetBSD/aarch64|aarch64]] for The Raspberry Pi looks for firmware and kernel.img on the first FAT32 MBR partition of the uSD card. A separate kernel (kernel7.img) is used on RPI2 and RPI3. The NetBSD kernel will then find NetBSD MBR partition and within that the root disklabel partition, and use that FFS partition as the root filesystem. -A 2 GB card is the smallest workable size, and the installation image will fit. After the first boot, the system resizes the NetBSD root partition to fill the card. Note that swap is after /boot and before /, and not contained in the NetBSD fdisk partition. However, if you don't try to change the partition structure, this should not cause you any trouble. +A 2 GB card is the smallest workable size that the installation image will fit on. After the first boot, the system resizes the NetBSD root partition to fill the card. Note that swap is after /boot and before /, and not contained in the NetBSD fdisk partition. However, if you don't try to change the partition structure, this should not cause you any trouble. Note that SD cards generally have limited write tolerance, so you may wish to disable atime updates via the noatime option, as is done by the default installation. ## Choosing a version -First, decide if you want to install a formal release (7.2 or 8.0), a stable branch build (netbsd-7, netbsd-8), or NetBSD-current. For people who don't know how to choose among those, a recent build of netbsd-8 is probably best, with 8.0 the choice for those who value being at exactly a formal release. +First, decide if you want to install a formal release (8.0 or 9.0), a stable branch build (netbsd-8, netbsd-9), or NetBSD-current. For people who don't know how to choose among those, a recent build of netbsd-9 is probably best, with 9.0 the choice for those who value being at exactly a formal release. See also "ebijun's image", below, which is NetBSD-current and includes packages. @@ -91,22 +116,22 @@ Consider setting RELEASEMACHINEDIR if yo ### NetBSD autobuild HTTPS/FTP servers -NetBSD provides nightly builds on [nyftp.netbsd.org](https://nyftp.netbsd.org/pub/NetBSD-daily/). The next directory level is the branch being built (netbsd-7, netbsd-8, HEAD, and more), plus optionally things like compiler type. It is followed by date/time, e.g. "HEAD/201811051650Z"; once a build is complete the symlink "latest" is adjusted to point to it. The next level is "${MACHINE}-${MACHINE_ARCH}", e.g. "evbarm-earmv7hf", and multiple combinations are provided. +NetBSD provides nightly builds on [nycdn.netbsd.org](https://nycdn.netbsd.org/pub/NetBSD-daily/). The next directory level is the branch being built (netbsd-8, netbsd-9, HEAD, and more), plus optionally things like compiler type. It is followed by date/time, e.g. "HEAD/201811051650Z"; once a build is complete the symlink "latest" is adjusted to point to it. The next level is "${MACHINE}-${MACHINE_ARCH}", e.g. "evbarm-earmv7hf", and multiple combinations are provided. -An example URL, arguably the standard approach for first-time NetBSD/RPI users, is https://nyftp.netbsd.org/pub/NetBSD-daily/netbsd-8/latest/evbarm-earmv7hf/binary/gzimg/ +An example URL, arguably the standard approach for first-time NetBSD/RPI users, is ### release layout Once you get to the releasedir, self-built and autobuild releases have the same structure. - The 'evbarm-earmv6hf/binary/gzimg/' directory contains an rpi.img file that will run on any of the RPI boards. - - The 'evbarm-earmv7hf/binary/gzimg/' directory contains an armv7.img file that uses the armv7 instruction set, and thus can run only on the Raspberry Pi 2/3. + - The 'evbarm-earmv7hf/binary/gzimg/' directory contains an armv7.img file that uses the armv7 instruction set, and thus can run only on the RPI2 and RPI3 (and perhaps the CM3). It also supports systems other than the RPI family. \todo Explain why there is no armv7_inst.gz. ## Preparing a uSD card -Once you have rpi.img.gz (or rpi_inst), put it on a uSD card using gunzip and dd, for example: +Once you have rpi.img.gz (or rpi_inst for earmv6 boards), put it on a uSD card using gunzip and dd, for example: - gunzip rpi.img.gz - dd if=rpi.img of=/dev/disk1 @@ -119,9 +144,9 @@ The standard approach is to use a USB ke By default the rpi.img is set to use the HDMI output. If you wish to use a serial console, mount the FAT32 partition on another system and edit cmdline.txt and remove '"console=fb"'. - - Most (all?) USB-to-TTL serial adapters have wires for Tx, Rx and ground, and not RTS/CTS or other flow control lines. Thus, your terminal program (or terminal) must be configured to not require flow control; a symptom of misconfiguration is that you see console output, but cannot type anything. If so, adjust your serial console application's flow control settings to "none". + - Most (all?) USB-to-TTL serial adapters have wires for TX, RX and ground, and not RTS/CTS or other flow control lines. Thus, your terminal program (or terminal) must be configured to not require flow control; a symptom of misconfiguration is that you see console output, but cannot type anything. If so, adjust your serial console application's flow control settings to "none". The serial port is at 115200 baud. - - In Kermit, the command is "set flow none". + - In Kermit, the commands are "set flow none", "set carrier-watch off", "set baud 115200", and, often on NetBSD, "set line /dev/dtyU0". - In minicom, run "minicom -s" and set hardware flow control to "no". ### Enabling ssh for installation without any console @@ -134,10 +159,10 @@ build.sh (and hence the FTP site) also c - Connect an Ethernet cable from the RPI to a LAN with a DHCP server, and another host you can use for ssh. - Power on the RPI, and wait. Watch the logs on the DHCP server, and find the IP address assigned to the RPI. - - Use ssh to login to the address you found with user "sysinst", and password "netbsd". + - Use ssh to log in to the address you found with user "sysinst", and password "netbsd". - When installing, ensure that you enable DHCP and ssh, so that you can log in again after the system is installed. -\todo Verify that the above is accurate and sufficient. +The rpi_inst.img.gz image will only work for systems that use earmv6hf kernels (so not RPI2/3). See [this port-arm message](https://mail-index.netbsd.org/port-arm/2017/08/18/msg004374.html) for details. ## Installation via ebijun's image @@ -147,7 +172,40 @@ is based on NetBSD-current and is built work on Raspberry Pi 1, 2 and 3. This image is typically updated every few weeks. - - [https://github.com/ebijun/NetBSD/blob/master/RPI/RPIimage/Image/README](https://github.com/ebijun/NetBSD/blob/master/RPI/RPIimage/Image/README) + - + +## Boot Process + +https://www.raspberrypi.org/documentation/configuration/config-txt/boot.md + +### DTBs + +Note that generally, a single dtb is loaded. On NetBSD 9, the dtb +file for the system is loaded by the bootloader (in flash). + +The RPI bootloader looks for a magic string in a trailer after the kernel to determine if it should use DTB support (the new normal) or something called ATAG (apparently the old way). See [upstream commit introducing DTB trailer](https://github.com/raspberrypi/linux/commit/2367d8a42e2717d8d15a39a9085cc2909fae033a#diff-8f088aca645d10d79b594d58db4136f3e09caee077fe373bb08f02f2040900a9) for more information. + +### Kernel format variants + +In netbsd-8, only the ELF and bin variants of RPI2 are built. The bin version is used. + +In netbsd-9 releasedir/binary/kernels, the following 4 versions of GENERIC are produced. (This might be the same in current.) + +#### netbsd-GENERIC.gz + +This is regular ELF and not used on RPI. + +#### netbsd-GENERIC.bin.gz + +It is unclear why this file exists on 9. It seems to be like img, but without the trailer for DTB; this makes sense for 8. + +#### netbsd-GENERIC.img.gz + +On NetBSD >=9, the kernel with the .img suffix has the trailer to cause the bootloader to load DTB files. + +#### netbsd-GENERIC.ub.gz + +This is for u-boot and not used on RPI. ## Configuring 802.11 @@ -161,32 +219,71 @@ Note that the built-in WiFi in the RPI3 The following pages have been published by NetBSD community members. (Note that some of them are old.) - - https://www.cambus.net/netbsd-on-the-raspberry-pi/ + - # Maintaining a system +## Booting single user + +\todo Describe how to boot single user via the serial console and via the fb console. + ## vcgencmd The program vcgencmd, referenced in the boot section, can be found in pkgsrc/misc/raspberrypi-userland. ## Updating the kernel - - Build a new kernel, e.g. using build.sh. It will tell you where the ELF version of the kernel is, e.g. - + - Run uname -a to determine the name of the config of your current kernel. For NetBSD <= 8, one ran RPI or RPI2. For NetBSD >=9, one uses GENERIC. + - Build a new kernel, e.g. using build.sh. Ideally, run "build.sh release" and look in releasedir/binary/kernels. If building just a kernel, it will tell you where the ELF version of the kernel is, e.g. ... - Kernels built from RPI2: - /Users/feyrer/work/NetBSD/cvs/src-current/obj.evbarm-Darwin-XXX/sys/arch/evbarm/compile/RPI2/netbsd + Kernels built from GENERIC: + /Users/feyrer/work/NetBSD/cvs/src-current/obj.evbarm-Darwin-XXX/sys/arch/evbarm/compile/GENERIC/netbsd ... - - - Besides the "netbsd" kernel in ELF format, there is also a "netbsd.img" (for current) or "netbsd.bin" (for 7 and 8) kernel that is in a format that the Raspberry can boot. + - There are multiple kernel formats produced by a release build, for use with different boot loader schemes.. For GENERIC: + - netbsd-GENERIC: A normal kernel in ELF format. + - netbsd-GENERIC.img: In NetBSD >= 9, formatted for the RPI bootloader. + - netbsd-GENERIC.bin: In NetBSD <= 8, formatted for the RPI bootloader. In NetBSD >= 9, ?????? In NetBSD 9, this kernel WILL NOT boot. + - netbsd-GENERIC.ub: A kernel in uboot format. - Depending on your hardware version, copy this either to /boot/kernel.img (First generation Pi, Pi Zero hardware) or to /boot/kernel7.img (Pi 2, Pi 3 hardware) - reboot +\todo Explain if updating firmware is necessary when e.g. moving from 8 to 9, or 9 to current. + +## Updating dtb files + +### NetBSD 8 + +On NetBSD 8, dtb files are not used. (\todo Really?) + +### NetBSD 9 + +(This is harder than it should be.) +Build a release. gunzip the armv7.img, vnconfig it, and mount the MSDOS partition (e) e.g. on /mnt. Copy the dtb files from /mnt/foo.dtb to /boot, and from /mnt/dtb/foo.dtb to /boot/dtb. + +It seems that some systems, including RPI, require dtb files in /boot, and some expect them in /boot/dtb. + +\todo Explain if you only really need the right one for your system type. + +\todo Explain how one is supposed to be able to update these from the dtb files in releasedir/binary/kernel, or fix it to have the same structure. + +### NetBSD current + +When updating, ensure that /boot is mounted and that you unpack the dtb set. + ## Updating the firmware +It is highly likely that running NetBSD from a given branch X with firmware from a branch Y < X will not go well. It is unclear if firmware from a branch Y > X will work. It is standard practice to use firmware from the right branch. + A section below describes the process of updating NetBSD's copy of the firmware from upstream, with testing, by NetBSD developers. This section is about updating a system's firmware from the firmware in a version of NetBSD. -\todo Explain where the firmware is in the source tree, and if it is in the installed system image (such as /usr/mdec). Explain how to update a system (presumably /boot) from either an installed system's new firmware files, or the source tree. Explain any particular cautions. +(Updating the firmware is harder than it should be.) +Build a release. gunzip the armv7.img, vnconfig it, and mount the MSDOS partition (e) e.g. on /mnt. Copy files from that to /boot that have changes, carefully. + +Relevant files include bootcode.bin, start.elf and start_cd.elf. + +Compare cmdline.txt, but beware that just overwriting it will lose customizations like using the serial console instead of the framebuffer. + +\todo Explain where the firmware is in the source tree, and note that it is not in the installed system image (such as /usr/mdec). Explain how to update a system (presumably /boot) from either an installed system's new firmware files, or the source tree. Explain any particular cautions. \todo Explain if using updated firmware from one branch (e.g. netbsd-current) on a system using a different branch (e.g. netbsd-8) is safe. Explain if pullups are done to release branches with new firmware. @@ -194,30 +291,35 @@ A section below describes the process of The device boots by finding a file "bootcode.bin". The primary location is a FAT32 partition on the uSD card, and an additional location is on a USB drive. See the [upstream documentation on booting](https://www.raspberrypi.org/documentation/hardware/raspberrypi/bootmodes/) and read all the subpages. -The standard approach is to use a uSD card, with a fdisk partition table containing a FAT32 partition marked active, and a NetBSD partition. The NetBSD partition will then contain a disklabel, pointing to an FFS partition (a), a swap paritiion (b) and the FAT32 boot partition mounted as /boot (e). The file /boot/cmdline.txt has a line to set the root partition. +The standard approach is to use a uSD card, with a fdisk partition table containing a FAT32 partition marked active, and a NetBSD partition. The NetBSD partition will then contain a disklabel, pointing to an FFS partition (a), a swap partition (b) and the FAT32 boot partition mounted as /boot (e). The file /boot/cmdline.txt has a line to set the root partition. -One wrinkle in the standard approach is that the disk layout is "boot swap /", but the NetBSD fdisk partition starts at the location of /. The / partition can hold a disklabel, while swap cannot. It is normal to have swap after / (and thus within the fdisk partition), but the arrangement used permits growing / on first boot, for the typical case where a larger uSD is used, compared to the minimum image size. +One wrinkle in the standard approach is that the disk layout is "boot swap /", but the NetBSD fdisk partition starts at the location of /, so the swap partition is not within the NetBSD fdisk partition. The / partition can hold a disklabel, while swap cannot. It is normal to have swap after / (and thus within the fdisk partition), but the arrangement used permits growing / on first boot, for the typical case where a larger uSD is used, compared to the minimum image size. An alternate approach is to have the boot FAT32 partition as above, but to have the entire system including root on an external disk. This is configured by changing root=ld0a to root=sd0a or root=dk0 (depending on disklabel/GPT). Besides greater space, part of the point is to avoid writing to the uSD card. -A third approach, workable on the Pi 3 only, is to configure USB host booting (already enableed on the 3+; see the upstream documentation) and have the boot partition also on the external device. In this case the external device must have an MBR because the hardware's first-stage boot does not have GPT support. In theory the [procedure to program USB host boot mode](https://www.raspberrypi.org/documentation/hardware/raspberrypi/bootmodes/msd.md) will function on a NetBSD system because the programming is done by bootcode.bin. +A third approach, workable on the Pi 3 only, is to configure USB host booting (already enabled on the 3+; see the upstream documentation) and have the boot partition also on the external device. In this case the external device must have an MBR because the hardware's first-stage boot does not have GPT support. In theory the [procedure to program USB host boot mode](https://www.raspberrypi.org/documentation/hardware/raspberrypi/bootmodes/msd.md) will function on a NetBSD system because the programming is done by bootcode.bin. \todo Confirm that putting program_usb_boot_mode=1 in config.txt and booting works to program the OTP bit. Confirm that one can then boot NetBSD from external USB. -\todo Explain USB enumeration and how to ensure that the correct boot and root devices are found if one has e.g. a small SSD for the system and a big disk. +There is no well-defined USB enumeration order, so the preferred approach if one has multiple USB mass storage devices is to use named wedges in both fstab and cmdline.txt. -# X11 and GPU +## Split-mode aarch32/aarch64 -## Console font +\todo Verify this, and add any necessary cautions about boot code. -Some find the default font to be too small. \todo Give a link to the normal instructions on how to change it. +The aarch64 kernel can run aarch32 binaries, so one can boot an aarch64 kernel on a system with an aarch32 userland. + +# X11 and GPU ## Video playback -Accelerated video playback is supported in NetBSD 7 with the [OMXPlayer](http://pkgsrc.se/multimedia/omxplayer) application and through GStreamer with the [omx](http://pkgsrc.se/multimedia/gst-plugins1-omx) plugin. + +Accelerated video playback is supported with the [OMXPlayer](http://pkgsrc.se/multimedia/omxplayer) application and through GStreamer with the [omx](http://pkgsrc.se/multimedia/gst-plugins1-omx) plugin. ## OpenGL ES -Accelerated OpenGL ES is supported in NetBSD 7. The GL ES client libraries are included with the [misc/raspberrypi-userland](http://pkgsrc.se/misc/raspberrypi-userland) package. + +Accelerated OpenGL ES is supported. The GL ES client libraries are included with the [misc/raspberrypi-userland](http://pkgsrc.se/misc/raspberrypi-userland) package. ## Quake 3 + A Raspberry Pi optimized build of *ioquake3* is available in the [games/ioquake3-raspberrypi](http://pkgsrc.se/games/ioquake3-raspberrypi) package. To use it, the following additional resources are required: - pak0.pk3 from Quake 3 CD @@ -227,19 +329,18 @@ A Raspberry Pi optimized build of *ioqua Place the pak0.pk3 file in the /usr/pkg/lib/ioquake3/baseq3 directory. ## RetroArch / Libretro + Using [emulators/retroarch](http://pkgsrc.se/emulators/retroarch) it is possible to run many emulators at full speed the Raspberry Pi. Emulator cores for various gaming consoles are available in the [emulators/libretro-*](http://pkgsrc.se/search.php?so=libretro-) packages. To begin using retroarch: - Install [emulators/retroarch](http://pkgsrc.se/emulators/retroarch) - Install the libretro core for the system you would like to emulate (lets take [emulators/libretro-gambatte](http://pkgsrc.se/emulators/libretro-gambatte), a GameBoy Color emulator, as an example). - - Plug in a USB HID compatible Gamepad, such as the Logitech F710 in "DirectInput" mode (set "D/X" switch to "D"). - - Create a config file for your gamepad using *retroarch-joyconfig*. -[[!template id=programlisting text=""" -$ retroarch-joyconfig -o gamepad.cfg -"""]] - - Launch the emulator from the command-line (no X required): -[[!template id=programlisting text=""" -$ retroarch --appendconfig gamepad.cfg -L /usr/pkg/lib/libretro/gambatte_libretro.so game.gbc -"""]] + - Make sure your user has read and write permissions on `/dev/vchiq`. + - Plug in a USB HID compatible Gamepad, such as the Logitech F710 in "DirectInput" mode (set "D/X" switch to "D"). Note that since the framebuffer GL driver will not allow for keyboard input in RetroArch, you will have to copy your joypad configuration from another system. + - Configure retroarch by editing $HOME/.config/retroarch/retroarch.cfg: + video_driver = "gl" + input_driver = "null" + joypad_driver = "sdl2" + menu_driver = "rgui" # Developer notes @@ -265,8 +366,36 @@ Tests should be run on all of `rpi[0123] ## Testing with anita and qemu -anita has support for evbarm. Install qemu and dtb-arm-vexpress from pkgsrc. Note that the release subdirectory should be evbarm-earmv6hf or evbarm-earmv7hf. +See the anita section in the evbarm page. + +It is not currently known how to emulate a RPI in qemu, and therefore anita does not yet have support for this. \todo Add a command-line example to run qemu emulating some RPI model. + +# Misc notes + +Miscellaneous notes about Raspberry PI. + +## Power supply needed (or: why there is a little rainbow square in the top-right corner?) + +Raspberry Pi devices are powered by 5V micro USB and a 2.5A (2500mA) +power supply is recommended. For more information please read: + + + +Power glitches can also manifest in other ways, e.g. with an USB +disk plugged: + +[[!template id=programlisting text=""" +sd0(umass0:0:0:0): generic HBA error +sd0: cache synchronization failed +"""]] + +Using a recommended power supply avoid such issues. + +## Xenon death flash (Raspberry Pi 2 is camera-shy) + +When using laser pointers or xenon flashes in cameras (or other +flashes of high-intensity long-wave light) against a Raspberry Pi +2 the Pi can power itself off. +For more information please read: -\todo Explain how to select various RPI models to emulate. -\todo Explain about how DTB works. -\todo Give a command line example to run qemu (without anita). +