File:  [NetBSD Developer Wiki] / wikisrc / ports / evbarm / raspberry_pi.mdwn
Revision 1.96: download - view: text, annotated - select for diffs
Tue Nov 6 17:34:03 2018 UTC (2 years, 10 months ago) by gdt
Branches: MAIN
CVS tags: HEAD
raspberry_pi: add questions

    1: [[!meta title="NetBSD/evbarm on Raspberry Pi"]]
    3: This page attempts to document and coordinate efforts towards NetBSD/evbarm on [Raspberry Pi]( All board variants are supported.
    5: 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.)
    7: [[images/raspberrypi.jpg]]
    9: [[!toc levels=2]]
   11: <small>([Raspberry Pi image]( by Christopher Lee used under CC-By-2.0 license)</small>
   13: # What works (and what doesn't yet)
   15: \todo Add information  on Pi Zero and Pi Zero W.
   17: ## NetBSD 7 and NetBSD 8
   19:  - RaspberryPi 1, 2, 3 (except Pi 3 builtin WiFi and bluetooth)
   20:  - multiple processors on 2/3
   21:  - boots normally to multiuser, with FAT32 boot partition on uSD
   22:  - root filesystem can be uSD or USB-attached mass storage
   23:  - serial or graphics console (with EDID query / parsing)
   24:  - X11 via HDMI
   25:  - GPU (VCHIQ) - 3D and video decode. man page missing.
   26:  - USB host controller - dwctwo(4) and most devices work
   27:  - USB Ethernet - usmsc(4)
   28:  - DMA controller driver and sdhc(4) support
   29:  - RNG
   30:  - Audio: works. man page missing.
   31:  - GPIO
   32:  - I²C: works, could use enhancements, man page
   33:  - SPI: could use enhancements, man page
   35: ## NetBSD current
   37:  - Raspberry Pi 3 builtin bluetooth
   38:  - Raspberry Pi 3 new SD host controller driver
   40: ## What needs work
   42:  - USB (host); isochronous transfers.
   43:  - Raspberry Pi 3 builtin WiFi
   45: # CPU types
   47:  - Raspberry Pi 1 uses "earmv6hf".
   48:  - Raspberry Pi Zero uses "\todo".
   49:  - Raspberry Pi 2 uses "earmv7hf".
   50:  - Raspberry Pi 3 uses "earmv7hf".
   51:  - Raspberry Pi Zero W uses "\todo".
   53: 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.
   55: \todo Explain if systems built with earm or earmv5 will work on RPI or RPI2/3.
   57: See also [[NetBSD/aarch64|aarch64]] for running the Pi 2/3 in 64-bit mode.
   59: # Installation
   61: ## SD card structure
   63: 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.
   64: 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.
   66: 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.
   68: 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.
   70: ## Choosing a version
   72: 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.
   74: See also "ebijun's image", below, which is NetBSD-current and includes packages.
   76: ## Getting bits to install
   78: You can either build a release yourself with, or get a release from the NetBSD HTTPS/FTP servers.  The bits from both sources should match, except for things like  timestamps, or because the sources are from slightly different points along branches.
   80: ### Building yourself
   82: Getting sources and building a release with is not special for evbarm.  However, the evbarm port has a very large number of CPU types, compared to i386 and amd64 which have one each.  The standard approach is to use -m to define MACHINE and -a to define MACHINE_ARCH. supports aliases that can be passed as a MACHINE value, but denote both MACHINE and a MACHINE_ARCH.   The third line uses an alias and is equal to the second, for RPI2/3.  Note that the aliases start with "evb" while the MACHINE_ARCH values do not, and that aliases have "-el" or "-eb", while the MACHINE_ARCH values have no suffix or "eb".
   84:  - ./ -m evbarm -a earmv6hf -u release
   85:  - ./ -m evbarm -a earmv7hf -u release
   86:  - ./ -m evbearmv7hf-el -u release
   88: Consider setting RELEASEMACHINEDIR if you wish to build multiple MACHINE_ARCH values for a MACHINE; see  Use something like "evbarm-earmv7hf", so that 1) earvm6 and earmv7 don't collide and 2) anita will recognize it as a type of evbarm.
   90: ### NetBSD autobuild HTTPS/FTP servers
   92: NetBSD provides nightly builds on [](  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.
   94: An example URL, arguably the standard approach for first-time NetBSD/RPI users, is
   96: ### release layout
   98: Once you get to the releasedir, self-built and autobuild releases have the same structure.
  100:  - The 'evbarm-earmv6hf/binary/gzimg/' directory contains an rpi.img file that will run on any of the RPI boards.
  101:  - 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.
  103: \todo Explain why there is no armv7_inst.gz.
  105: ## Preparing a uSD card
  107: Once you have rpi.img.gz (or rpi_inst), put it on a uSD card using gunzip and dd, for example:
  109:  - gunzip rpi.img.gz
  110:  - dd if=rpi.img of=/dev/disk1
  112: ## Console approaches
  114: The standard approach is to use a USB keyboard and an HDMI monitor for installation.
  116: ### Serial Console
  118: 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"'.
  120:  - 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".
  122:    - In Kermit, the command is "set flow none".
  123:    - In minicom, run "minicom -s" and set hardware flow control to "no".
  125: ### Enabling ssh for installation without any console
  127: If you want to enable ssh with the standard image, so that you can log in over the net without either a serial or HDMI console, you can edit the configuration of a uSD card before booting.   On another computer, mount the ffs partition, place /root/.ssh/authorized_keys, uncomment PermitRootLogin in /etc/ssh/sshd_config, and comment out the rc_configure=NO in /etc/rc.conf.  Besides having to find the IP address (e.g. from DHCP server logs), you will have to wait for the partition resizing and reboot.
  129: ### Installation with sshramdisk image
  131: (and hence the FTP site) also creates an image 'rpi_inst.img.gz' specifically for installation without HDMI or a serial console, when built for earmv6hf.  Note that this image is much smaller and that you will need to fetch the sets over the network.  To use this method, write that image to a uSD card as above, and then:
  133:  - Connect an Ethernet cable from the RPI to a LAN with a DHCP server, and another host you can use for ssh.
  134:  - Power on the RPI, and wait.  Watch the logs on the DHCP server, and find the IP address assigned to the RPI.
  135:  - Use ssh to login to the address you found with user "sysinst", and password "netbsd".
  136:  - When installing, ensure that you enable DHCP and ssh, so that you can log in again after the system is installed.
  138: \todo Verify that the above is accurate and sufficient.
  140: ## Installation via ebijun's image
  142: As an alternative to the standard installation images, Jun Ebihara
  143: provides an install image for Raspberry Pi that includes packages.  It
  144: is based on NetBSD-current and is built for earmv6hf, and thus will
  145: work on Raspberry Pi 1, 2 and 3.  This image is typically updated
  146: every few weeks.
  148:  - [](
  150: ## Links
  152: The following pages have been published by NetBSD community members.  (Note that some of them are old.)
  154:  -
  156: # Maintaining a system
  158: ## vcgencmd
  160: The program vcgencmd, referenced in the boot section,  can be found in pkgsrc/misc/raspberrypi-userland.
  162: ## Updating the kernel
  164:  - Build a new kernel, e.g. using It will tell you where the ELF version of the kernel is, e.g.
  166:          ...
  167:          Kernels built from RPI2:
  168:           /Users/feyrer/work/NetBSD/cvs/src-current/obj.evbarm-Darwin-XXX/sys/arch/evbarm/compile/RPI2/netbsd
  169:          ...
  171:  - 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.
  172:  - 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)
  173:  - reboot
  175: ## Updating the firmware
  177: 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.
  179: \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.
  181: ## Booting
  183: 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]( and read all the subpages.
  185: 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.
  187: 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.
  189: 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.
  191: 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]( will function on a NetBSD system because the programming is done by bootcode.bin.
  192: \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.
  194: \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.
  196: # Wireless Networking
  198: Note that the built-in WiFi in the RPI3 is not yet supported.   USB WiFi interfaces (that work on NetBSD in general) should all work.
  200:  - A Realtek 802.11n USB adaptor configures as urtwn(4).
  201:    - Configure with wpa_supplicant in /etc/rc.conf -
  203:            ifconfig_urtwn0=dhcp
  204:            dhcpcd=YES
  205:            dhcpcd_flags="-q -b"
  206:            wpa_supplicant=YES
  207:            wpa_supplicant_flags="-B -i urtwn0 -c /etc/wpa_supplicant.conf"
  208:    - A sample wpa_supplicant.conf can be found at /usr/share/examples/wpa_supplicant/wpa_supplicant.conf
  210: # X11 and GPU
  212: ## Console font
  214: Some find the default font to be too small.  \todo Give a link to the normal instructions on how to change it.
  216: ## Video playback
  217: Accelerated video playback is supported in NetBSD 7 with the [OMXPlayer]( application and through GStreamer with the [omx]( plugin.
  219: ## OpenGL ES
  220: Accelerated OpenGL ES is supported in NetBSD 7. The GL ES client libraries are included with the [misc/raspberrypi-userland]( package.
  222: ## Quake 3
  223: A Raspberry Pi optimized build of *ioquake3* is available in the [games/ioquake3-raspberrypi]( package. To use it, the following additional resources are required:
  225:  - pak0.pk3 from Quake 3 CD
  226:  - additional pak files from the [games/ioquake3-pk3]( package
  227:  - read/write permissions on /dev/vchiq and /dev/wsmouse
  229: Place the pak0.pk3 file in the /usr/pkg/lib/ioquake3/baseq3 directory.
  231: ## RetroArch / Libretro
  232: Using [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-*]( packages. To begin using retroarch:
  234:  - Install [emulators/retroarch](
  235:  - Install the libretro core for the system you would like to emulate (lets take [emulators/libretro-gambatte](, a GameBoy Color emulator, as an example).
  236:  - Plug in a USB HID compatible Gamepad, such as the Logitech F710 in "DirectInput" mode (set "D/X" switch to "D").
  237:  - Create a config file for your gamepad using *retroarch-joyconfig*.
  238: [[!template  id=programlisting text="""
  239: $ retroarch-joyconfig -o gamepad.cfg
  240: """]]
  241:  - Launch the emulator from the command-line (no X required):
  242: [[!template  id=programlisting text="""
  243: $ retroarch --appendconfig gamepad.cfg -L /usr/pkg/lib/libretro/ game.gbc
  244: """]]
  246: # Developer notes
  248: These notes are for people working on improvements to RPI support in NetBSD.
  250: ## Updating the firmware version in the NetBSD sources
  252: (Note that trying new firmware may result in a non-bootable system, so
  253: be prepared to recover the bootable media with another system.)
  255: Upstream firmware releases are
  256: [on GitHub](
  257: Copy all files except `kernel*.img` into `/boot` and reboot.
  259: New firmware should pass all of the following tests before being committed to NetBSD.
  261: - Audio
  262: - OMXPlayer (and [[!template id=man name="vchiq"]])
  263: - Serial/framebuffer console
  264: - CPU frequency scaling
  266: Tests should be run on all of `rpi[0123]`.
  268: ## Testing with anita and qemu
  270: 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.
  272: \todo Explain how to select various RPI models to emulate.
  273: \todo Explain about how DTB works.

CVSweb for NetBSD wikisrc <> software: FreeBSD-CVSweb