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[[!meta title="NetBSD/evbarm on Raspberry Pi"]]	[[!meta title="NetBSD/evbarm on Raspberry Pi"]]

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 32-bit (aarch32) centric, as that has been until mid-2018 the only approach.	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.

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 later, but note that everyone uses 8 or -current.)	Initial 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.

In mid-2018, -current gained support for 64-bit ARM (aarch64) support. This will be in NetBSD 9.

[[images/raspberrypi.jpg]]	[[images/raspberrypi.jpg]]

Line 12 In mid-2018, -current gained support for	Line 10 In mid-2018, -current gained support for

<small>([Raspberry Pi image](http://www.flickr.com/photos/42325803@N07/8118758647/) by Christopher Lee used under CC-By-2.0 license)</small>	<small>([Raspberry Pi image](http://www.flickr.com/photos/42325803@N07/8118758647/) by Christopher Lee used under CC-By-2.0 license)</small>

# What works (and what doesn't yet)	# What works

"Works" is primarily relative to the earmv6hf-el and earmv7hf-el CPU targets (32-bit).

## NetBSD 7 and NetBSD 8	## NetBSD 8

- RPI1, RPI2, RPI2-1.2, RPI3, RPI3+ (except RPI3 builtin WiFi and bluetooth)	- 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?)	- RPI0 and RPI0W are expected to work (without WiFi, and one needs fdt files \todo where from?)
Line 27 In mid-2018, -current gained support for	Line 23 In mid-2018, -current gained support for
- X11 via HDMI	- X11 via HDMI
- GPU (VCHIQ) - 3D and video decode. man page missing.	- GPU (VCHIQ) - 3D and video decode. man page missing.
- USB host controller - dwctwo(4) and most devices work	- USB host controller - dwctwo(4) and most devices work
- USB Ethernet - usmsc(4)	- Ethernet - usmsc(4), mue(4)
- DMA controller driver and sdhc(4) support	- DMA controller driver and sdhc(4) support
- RNG	- RNG
- Audio: works. man page missing.	- Audio: works. man page missing.
Line 42 In mid-2018, -current gained support for	Line 38 In mid-2018, -current gained support for

## NetBSD current	## NetBSD current

	- RPI4 (using EDK2 UEFI firmware)
	- RPI4 Ethernet (Broadcom GENETv5) - genet(4)
	- RPI3/RPI4 audio with aarch64 kernels
	- Previously the driver was only included with 32-bit (ARMv7/ARMv6)
	kernels and images due to the Broadcom code having 64-bit cleanliness
	issues.
- RPI3 builtin bluetooth	- RPI3 builtin bluetooth
	- RPI3 and RPI0W builtin WiFi - bwfm(4)
## (maybe) NetBSD current, with manual steps	- Big endian support

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, RPI0W builtin WiFi

## What needs documenting if it works	## What needs documenting if it works

Line 58 In mid-2018, -current gained support for	Line 56 In mid-2018, -current gained support for

## What needs work	## What needs work

- RPI4 (as of 2020-01, still does not work in current)
- USB (host); isochronous transfers.	- USB (host); isochronous transfers.
- RPI0W Bluetooth Low Energy (probably)	- RPI0W Bluetooth Low Energy (probably)
	- DRM/KMS

# CPU types	# CPU types

Line 68 In mid-2018, -current gained support for	Line 66 In mid-2018, -current gained support for
- RPI0 uses "earmv6hf".	- RPI0 uses "earmv6hf".
- RPI0W uses "earmv6hf".	- RPI0W uses "earmv6hf".
- RPI2 uses "earmv7hf".	- RPI2 uses "earmv7hf".
- RPI2-1.2 uses "earmv7hf" or "aarch64" (armv8 CPU hardware)	- RPI2-1.2 uses "earmv7hf" or "aarch64" (ARMv8 CPU hardware)
- RPI3 uses "earmv7hf" or "aarch64" (armv8 CPU hardware)	- RPI3 uses "earmv7hf" or "aarch64" (ARMv8 CPU hardware)
	- RPI4 uses "aarch64" (ARMv8 CPU hardware)

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.	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. In theory the code compiled for earmv7hf will be faster, but anecdotal experience is that it doesn't matter that much. Builds of NetBSD for earlier revisions of ARM are unsupported.

In theory the code compiled for earmv7hf will be faster, but anecdotal experience is that it doesn't matter that much.	# Installation

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 with older CPU architectures (earm, earmv4, earmv5) are not expected to work on RPI.	## Using standard images

The RPI2-1.2 and RPI3 have an armv8 CPU that supports aarch64 (64-bit	The simplest way is to download the appropriate SD card image from the NetBSD mirrors:
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	- The Raspberry Pi 1 requires the ARMv6 [rpi.img.gz](http://nycdn.netbsd.org/pub/NetBSD-daily/netbsd-9/latest/evbarm-earmv6hf/binary/gzimg/rpi.img.gz).
	- The Raspberry Pi 2-3 can use the standard ARMv7 [armv7.img.gz](https://nycdn.netbsd.org/pub/NetBSD-daily/netbsd-9/latest/evbarm-earmv7hf/binary/gzimg/armv7.img.gz) image.
	- The Raspberry Pi 3 can also use [arm64.img.gz](https://nycdn.netbsd.org/pub/NetBSD-daily/netbsd-9/latest/evbarm-aarch64/binary/gzimg/arm64.img.gz).

## SD card structure	Decompress it and write it to the SD card:

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.	$ gunzip armv7.img.gz
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.	$ dd if=armv7.img of=/dev/rld0d conv=sync bs=1m progress=1

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.	If you're not using NetBSD, your operating system's dd command's arguments may vary. On Windows, try [Rawrite32](https://www.netbsd.org/~martin/rawrite32/).

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.	The Raspberry Pi 4 requires the [UEFI firmware](https://github.com/pftf/RPi4/releases). Write the UEFI firmware to the SD card, and then insert an USB drive with the standard NetBSD `arm64.img` written to it. The Pi will then boot from USB.

## Choosing a version	The Raspberry Pi 3 can also [boot NetBSD from UEFI firmware](https://washbear.neocities.org/rpi3-netbsd-uefi.html), but the installation process is currently more complicated. However, there are some advantages, so you might want to try anyway.

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.	## SD card structure

See also "ebijun's image", below, which is NetBSD-current and includes packages.	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.

## Getting bits to install	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.

You can either build a release yourself with build.sh, 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.	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.

### Building yourself	## Building yourself

Getting sources and building a release with build.sh 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. build.sh 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".	Getting sources and building a release with build.sh 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. build.sh 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".

Line 114 Getting sources and building a release w	Line 112 Getting sources and building a release w

Consider setting RELEASEMACHINEDIR if you wish to build multiple MACHINE_ARCH values for a MACHINE; see build.sh. 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.	Consider setting RELEASEMACHINEDIR if you wish to build multiple MACHINE_ARCH values for a MACHINE; see build.sh. 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.

### NetBSD autobuild HTTPS/FTP servers

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-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.

An example URL, arguably the standard approach for first-time NetBSD/RPI users, is https://nycdn.netbsd.org/pub/NetBSD-daily/netbsd-8/latest/evbarm-earmv7hf/binary/gzimg/

### 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 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 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

## Console approaches	## Console approaches

The standard approach is to use a USB keyboard and an HDMI monitor for installation.	The standard approach is to use a USB keyboard and an HDMI monitor for installation.
Line 144 The standard approach is to use a USB ke	Line 120 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"'.	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".	- In minicom, run "minicom -s" and set hardware flow control to "no".

### Enabling ssh for installation without any console	### Enabling ssh for installation without any console
Line 159 build.sh (and hence the FTP site) also c	Line 135 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.	- 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.	- 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.	- When installing, ensure that you enable DHCP and ssh, so that you can log in again after the system is installed.

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.	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.
Line 174 every few weeks.	Line 150 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	## Configuring 802.11

After installation, the Ethernet will function as on any other NetBSD system; simply enable dhcpcd or configure a static address. USB WiFi devices will also function as on any other NetBSD system; in addition to dhcpcd or static, configure and enable wpa_supplicant.	After installation, the Ethernet will function as on any other NetBSD system; simply enable dhcpcd or configure a static address. USB WiFi devices will also function as on any other NetBSD system; in addition to dhcpcd or static, configure and enable wpa_supplicant.
Line 186 Note that the built-in WiFi in the RPI3	Line 195 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.)	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/	- <https://www.cambus.net/netbsd-on-the-raspberry-pi/>

# Maintaining a system	# Maintaining a system

	## Booting single user

	\todo Describe how to boot single user via the serial console and via the fb console.

## vcgencmd	## vcgencmd

The program vcgencmd, referenced in the boot section, can be found in pkgsrc/misc/raspberrypi-userland.	The program vcgencmd, referenced in the boot section, can be found in pkgsrc/misc/raspberrypi-userland.

## Updating the kernel	## 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:	Kernels built from GENERIC:
/Users/feyrer/work/NetBSD/cvs/src-current/obj.evbarm-Darwin-XXX/sys/arch/evbarm/compile/RPI2/netbsd	/Users/feyrer/work/NetBSD/cvs/src-current/obj.evbarm-Darwin-XXX/sys/arch/evbarm/compile/GENERIC/netbsd
...	...
	- There are multiple kernel formats produced by a release build, for use with different boot loader schemes.. For GENERIC:
- 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.	- 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)	- 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	- 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.

	### NetBSD 9

	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.

	### NetBSD current

	When updating, ensure that /boot is mounted and that you unpack the dtb set.

## Updating the firmware	## 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.	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.

Probably, for the RPI3+, one needs to use -current, or use -8 with firmware from -current. \todo Defuzz.	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.	\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.

Line 227 One wrinkle in the standard approach is	Line 268 One wrinkle in the standard approach is

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.	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 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.

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.	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.
Line 236 There is no well-defined USB enumeration	Line 277 There is no well-defined USB enumeration

\todo Verify this, and add any necessary cautions about boot code.	\todo Verify this, and add any necessary cautions about boot code.

The aarch64 kernel can run aarch32 binaries, so one can boot a aarch64 kernel on a system with aarch32 userland.	The aarch64 kernel can run aarch32 binaries, so one can boot an aarch64 kernel on a system with an aarch32 userland.

# X11 and GPU	# X11 and GPU

	Video acceleration currently only works with 32-bit (ARMv7 and ARMv6) kernels due to the Broadcom code not being 64-bit clean.

	Since applications require specialized support for the GPU, only a few applications are normally accelerated. NetBSD/aarch64 normally uses `llvmpipe` to provide fast parallel CPU-driven support for OpenGL, so should be faster when running normal applications.

	The situation should be improved, ideally by writing a DRM/KMS driver.

## Video playback	## 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	## 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	## 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:	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	- pak0.pk3 from Quake 3 CD
Line 256 A Raspberry Pi optimized build of *ioqua	Line 306 A Raspberry Pi optimized build of *ioqua
Place the pak0.pk3 file in the /usr/pkg/lib/ioquake3/baseq3 directory.	Place the pak0.pk3 file in the /usr/pkg/lib/ioquake3/baseq3 directory.

## RetroArch / Libretro	## 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:	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 [emulators/retroarch](http://pkgsrc.se/emulators/retroarch)
Line 296 See the anita section in the evbarm page	Line 347 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.	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	# Misc notes

Miscellaneous notes about Raspberry PI.	Miscellaneous notes about Raspberry PI.

## Power supply needed (or: why there is a little rainbow square in the top-right corner?)	## 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)	Raspberry Pi devices are powered by 5V micro USB and a 2.5A (2500mA)
power supply is recommended. For more information please read:	power supply is recommended. For more information please read:

Line 317 sd0: cache synchronization failed	Line 369 sd0: cache synchronization failed
Using a recommended power supply avoid such issues.	Using a recommended power supply avoid such issues.

## Xenon death flash (Raspberry Pi 2 is camera-shy)	## Xenon death flash (Raspberry Pi 2 is camera-shy)

When using laser pointers or xenon flashes in cameras (or other	When using laser pointers or xenon flashes in cameras (or other
flashes of high-intensity long-wave light) against a Raspberry Pi	flashes of high-intensity long-wave light) against a Raspberry Pi
2 the Pi can power itself off.	2 the Pi can power itself off.

CVSweb for NetBSD wikisrc <wikimaster@NetBSD.org> software: FreeBSD-CVSweb

Removed from v.1.126
changed lines
	Added in v.1.143