### Start VLC with MMAL Output Plugin

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

This command-line example shows how to start VLC using the `cvlc` command with the `mmal_vout` plugin for hardware-accelerated video output. It dynamically determines the correct HDMI display number and sets various VLC settings such as running in dummy mode (`-I dummy`), using MMAL for output (`--vout=mmal_vout`), enabling resizing (`--mmal-resize`), specifying the HDMI display (`--mmal-display hdmi-$MMAL_DISPLAY`), and disabling D-Bus (`--no-dbus`). This is useful for running VLC without an active display server.

```bash
DISPLAYNUM=$(tvservice -l | tail -c 2)
MMAL_DISPLAY=$(expr $DISPLAYNUM + 1)
VLC_SETTINGS="-I dummy --vout=mmal_vout --mmal-resize --mmal-display hdmi-$MMAL_DISPLAY --no-dbus"
cvlc $VLC_SETTINGS <video/playlist>
```

--------------------------------

### Raspberry Pi Yocto Build Workflow (Bash)

Source: https://context7.com/agherzan/meta-raspberrypi/llms.txt

This bash script outlines the complete workflow for building a Raspberry Pi image using Yocto. It includes installing 'kas', cloning repositories, building with 'kas', or setting up a traditional Yocto build environment, configuring layers, customizing 'local.conf', building the image with 'bitbake', and flashing it to an SD card.

```bash
#!/bin/bash
# Build workflow for Raspberry Pi 4 image

# 1. Install kas build tool
pip3 install kas

# 2. Clone the meta-raspberrypi layer
git clone https://github.com/agherzan/meta-raspberrypi.git
cd meta-raspberrypi

# 3. Build using kas
kas build kas-poky-rpi.yml

# 4. Or use traditional Yocto build setup
mkdir -p yocto-rpi && cd yocto-rpi
git clone https://git.yoctoproject.org/git/poky
git clone https://github.com/agherzan/meta-raspberrypi.git

source poky/oe-init-build-env build

# 5. Add layer to bblayers.conf
bitbake-layers add-layer ../meta-raspberrypi

# 6. Configure local.conf for Raspberry Pi 4
cat >> conf/local.conf << EOF
MACHINE = "raspberrypi4"
GPU_MEM = "256"
ENABLE_UART = "1"
ENABLE_I2C = "1"
ENABLE_SPI_BUS = "1"
RPI_EXTRA_CONFIG = "dtoverlay=gpio-shutdown,gpio_pin=3"
EOF

# 7. Build the image
bitbake core-image-base

# 8. Flash to SD card
sudo dd if=tmp/deploy/images/raspberrypi4/core-image-base-raspberrypi4.wic.bz2 of=/dev/sdX bs=4M status=progress

```

--------------------------------

### Raspberry Pi Hardware Configuration Examples (Bash)

Source: https://context7.com/agherzan/meta-raspberrypi/llms.txt

This section provides examples of common hardware configuration variables used in the 'local.conf' file for Raspberry Pi Yocto builds. These settings control features like GPU memory, UART, I2C, and SPI.

```bash
# local.conf configuration examples

# MACHINE = "raspberrypi4"
# GPU_MEM = "256"
# ENABLE_UART = "1"
# ENABLE_I2C = "1"
# ENABLE_SPI_BUS = "1"
# RPI_EXTRA_CONFIG = "dtoverlay=gpio-shutdown,gpio_pin=3"

```

--------------------------------

### Set Overclocking Options (Yocto/BitBake)

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Configures overclocking settings for Raspberry Pi devices, including CPU, GPU, and RAM frequencies, as well as core voltage. Supported variables are ARM_FREQ, GPU_FREQ, CORE_FREQ, SDRAM_FREQ, and OVER_VOLTAGE. Official 'Turbo Mode' settings are provided as an example.

```bitbake
ARM_FREQ = "1000"
CORE_FREQ = "500"
SDRAM_FREQ = "500"
OVER_VOLTAGE = "6"
```

--------------------------------

### Select Raspberry Pi Distro VLC and FFmpeg Providers

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

These configuration settings specify the preferred providers for VLC, FFmpeg, libav, and libpostproc to ensure the use of the Raspberry Pi Distro's optimized implementations. This is essential for utilizing hardware-accelerated video decoding through MMAL with VLC and FFmpeg, especially when running on a 64-bit OS where default support might be limited. These settings should be added to your `local.conf` file.

```none
PREFERRED_PROVIDER_vlc = "rpidistro-vlc"
PREFERRED_PROVIDER_ffmpeg = "rpidistro-ffmpeg"
PREFERRED_PROVIDER_libav = "rpidistro-ffmpeg"
PREFERRED_PROVIDER_libpostproc = "rpidistro-ffmpeg"
```

--------------------------------

### Add Purchased License Codecs (Yocto/BitBake)

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Enables the addition of purchased license codecs for media playback, such as MPG2 and WVC1. Users specify their license keys using KEY_DECODE_MPG2 and KEY_DECODE_WVC1 variables in local.conf. Multiple licenses can be added, separated by commas.

```bitbake
KEY_DECODE_MPG2 = "12345678"
KEY_DECODE_WVC1 = "0x12345678,0xabcdabcd,0x87654321"
```

--------------------------------

### Include Additional Files in SD Card Boot Partition (Deploy Directory)

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Specifies files from the build image deploy directory to be copied into the SD card's boot partition. DEPLOYPAYLOAD lists files and optional destination names, while RPI_SDIMG_EXTRA_DEPENDS ensures necessary deploy tasks are executed.

```none
DEPLOYPAYLOAD = "example1-${MACHINE}:example1 example2"
RPI_SDIMG_EXTRA_DEPENDS:append = " example:do_deploy"
```

--------------------------------

### Enable Raspberry Pi Camera Module V3

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Enables the Raspberry Pi Camera Module V3 by activating the unicam device and adding the imx708 device tree overlay to config.txt.

```shell
RASPBERRYPI_CAMERA_V3 = "1"
```

--------------------------------

### Enable WM8960 Soundcard Support

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Enables support for WM8960-based sound cards. Includes commands to adjust volume and toggle switches for optimal audio performance. Notes potential noise issues with specific audio capture devices.

```shell
MACHINE_FEATURES += "wm8960"
amixer -c1 sset 'Headphone',0 80%,80%
amixer -c1 sset 'Speaker',0 80%,80%
amixer -c1 sset 'Left Input Mixer Boost' toggle
amixer -c1 sset 'Left Output Mixer PCM' toggle
amixer -c1 sset 'Right Input Mixer Boost' toggle
amixer -c1 sset 'Right Output Mixer PCM' toggle
```

--------------------------------

### Manual config.txt Additions

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Allows manual addition of configuration lines to the `config.txt` file using the `RPI_EXTRA_CONFIG` variable. Supports multiple lines via `\n` separators and single quotes for strings containing double quotes.

```shell
RPI_EXTRA_CONFIG = ' \n \
    # Raspberry Pi 7" display/touch screen \n \
    lcd_rotate=2 \n \
    '
```

--------------------------------

### Configure Boot Delay (Yocto/BitBake)

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Adjusts or removes the delay between loading the GPU firmware and the kernel during boot. BOOT_DELAY controls the delay in seconds, and BOOT_DELAY_MS controls it in milliseconds. Setting these to "0" eliminates the delay.

```bitbake
BOOT_DELAY = "0"
BOOT_DELAY_MS = "0"
```

--------------------------------

### Include Additional Files in SD Card Boot Partition (Root Partition)

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Specifies files from the image's root partition to be copied into the SD card's boot partition. The FATPAYLOAD variable takes a space-separated list of file paths relative to the root partition.

```none
FATPAYLOAD = "/boot/example1 /boot/example2"
```

--------------------------------

### Create Custom Yocto Layer for Raspberry Pi

Source: https://context7.com/agherzan/meta-raspberrypi/llms.txt

Bash script to create a new Yocto Project custom layer extending meta-raspberrypi. Includes creating a custom machine configuration and an image recipe.

```bash
# Create custom layer structure
bitbake-layers create-layer meta-custom-rpi
cd meta-custom-rpi

# Create custom machine configuration
cat > conf/machine/custom-rpi4.conf << 'EOF'
require conf/machine/raspberrypi4.conf

# Custom configurations
GPU_MEM = "512"
MACHINE_FEATURES += "custom-feature"

# Add custom packages
MACHINE_EXTRA_RRECOMMENDS += "custom-app"
EOF

# Create custom image recipe
mkdir -p recipes-core/images
cat > recipes-core/images/custom-rpi-image.bb << 'EOF'
require recipes-core/images/rpi-test-image.bb

DESCRIPTION = "Custom Raspberry Pi image with additional packages"

IMAGE_INSTALL:append = " 
    python3 
    nodejs 
    custom-application 
    htop 
    vim 
"

IMAGE_FEATURES += "ssh-server-dropbear"
EOF

# Build the custom image
bitbake custom-rpi-image

```

--------------------------------

### Deploy Raspberry Pi Boot Files (BitBake)

Source: https://context7.com/agherzan/meta-raspberrypi/llms.txt

This BitBake recipe deploys configuration files for Raspberry Pi boot, including options for GPU memory, SPI, I2C, and VC4 graphics support. It modifies the 'config.txt' file based on environment variables.

```bitbake
DESCRIPTION = "Commented config.txt file for the Raspberry Pi"
LICENSE = "MIT"
COMPATIBLE_MACHINE = "^rpi$"

SRCREV = "6ac2d832c6c3b208e2669f50ec1abf2c20cb7ff4"
SRC_URI = "git://github.com/Evilpaul/RPi-config.git;protocol=https;branch=master"

inherit deploy nopackages

do_deploy() {
    install -d ${DEPLOYDIR}/${BOOTFILES_DIR_NAME}
    CONFIG=${DEPLOYDIR}/${BOOTFILES_DIR_NAME}/config.txt
    cp ${S}/config.txt $CONFIG

    # GPU memory configuration
    if [ -n "${GPU_MEM}" ]; then
        sed -i '/#gpu_mem=/ c\gpu_mem=${GPU_MEM}' $CONFIG
    fi

    # Enable SPI bus
    if [ "${ENABLE_SPI_BUS}" = "1" ]; then
        echo "dtparam=spi=on" >>$CONFIG
    fi

    # Enable I2C
    if [ "${ENABLE_I2C}" = "1" ]; then
        echo "dtparam=i2c1=on" >>$CONFIG
        echo "dtparam=i2c_arm=on" >>$CONFIG
    fi

    # VC4 Graphics support
    if [ "${VC4GRAPHICS}" = "1" ]; then
        echo "dtoverlay=${VC4DTBO}" >> $CONFIG
    fi
}

```

--------------------------------

### Enable Raspberry Pi Camera Module V2

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Enables the Raspberry Pi Camera Module V2 by activating the unicam device and adding the imx219 device tree overlay to config.txt. Also enables contiguous memory allocation in cmdline.txt.

```shell
RASPBERRYPI_CAMERA_V2 = "1"
```

--------------------------------

### Configure Boot Media (Yocto/BitBake)

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Selects the boot media for the Raspberry Pi 4, allowing booting from either SD card or USB memory. CMDLINE_ROOT_PARTITION specifies the root partition, and BOOT_MEDIA can be set to "mmc" or "usb". Default is SD card.

```bitbake
CMDLINE_ROOT_PARTITION = "/dev/sda2"
BOOT_MEDIA = "usb"
```

--------------------------------

### Create Raspberry Pi SD Card Image (BitBake Class)

Source: https://context7.com/agherzan/meta-raspberrypi/llms.txt

This BitBake class defines the process for creating bootable SD card images for Raspberry Pi, including partition layout and filesystem creation. It uses 'dd' and 'parted' for disk operations and 'mkfs.vfat' for the boot partition.

```bitbake
# classes/sdcard_image-rpi.bbclass
inherit image_types

# Disk layout:
#    0                      -> IMAGE_ROOTFS_ALIGNMENT (4MiB) - reserved
#    IMAGE_ROOTFS_ALIGNMENT -> BOOT_SPACE (48MiB)             - boot partition
#    BOOT_SPACE             -> SDIMG_SIZE                     - rootfs partition

BOOT_SPACE ?= "49152"
IMAGE_ROOTFS_ALIGNMENT = "4096"
SDIMG_ROOTFS_TYPE ?= "ext3"

IMAGE_CMD:rpi-sdimg () {
    # Align partitions
    BOOT_SPACE_ALIGNED=$(expr ${BOOT_SPACE} + ${IMAGE_ROOTFS_ALIGNMENT} - 1)
    BOOT_SPACE_ALIGNED=$(expr ${BOOT_SPACE_ALIGNED} - ${BOOT_SPACE_ALIGNED} % ${IMAGE_ROOTFS_ALIGNMENT})

    # Initialize SD card image
    dd if=/dev/zero of=${SDIMG} bs=1024 count=0 seek=${SDIMG_SIZE}

    # Create partition table
    parted -s ${SDIMG} mklabel msdos
    parted -s ${SDIMG} unit KiB mkpart primary fat32 ${IMAGE_ROOTFS_ALIGNMENT} $(expr ${BOOT_SPACE_ALIGNED} \+ ${IMAGE_ROOTFS_ALIGNMENT})
    parted -s ${SDIMG} set 1 boot on
    parted -s ${SDIMG} -- unit KiB mkpart primary ext2 $(expr ${BOOT_SPACE_ALIGNED} \+ ${IMAGE_ROOTFS_ALIGNMENT}) -1s

    # Create boot partition
    mkfs.vfat -F32 -n "${BOOTDD_VOLUME_ID}" -S 512 -C ${WORKDIR}/boot.img $BOOT_BLOCKS
    mcopy -v -i ${WORKDIR}/boot.img -s ${DEPLOY_DIR_IMAGE}/${BOOTFILES_DIR_NAME}/* ::/

    # Write partitions to image
    dd if=${WORKDIR}/boot.img of=${SDIMG} conv=notrunc seek=1 bs=$(expr ${IMAGE_ROOTFS_ALIGNMENT} \* 1024)
    dd if=${SDIMG_ROOTFS} of=${SDIMG} conv=notrunc seek=1 bs=$(expr 1024 \* ${BOOT_SPACE_ALIGNED} + ${IMAGE_ROOTFS_ALIGNMENT} \* 1024)
}

```

--------------------------------

### Configure Boot to U-Boot Bootloader

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Configures the system to use U-Boot as the primary bootloader, which will load the kernel image. Set RPI_USE_U_BOOT to '1' in local.conf. This may require specific UART configurations for certain Raspberry Pi models.

```none
RPI_USE_U_BOOT = "1"
```

--------------------------------

### Yocto Layer Configuration and Dynamic Layers (BitBake)

Source: https://context7.com/agherzan/meta-raspberrypi/llms.txt

Configures how BitBake finds and processes recipes within the meta-raspberrypi layer. It defines the layer's scope, priority, and compatibility, and enables dynamic inclusion of optional layers like OpenEmbedded and Qt5. Dependencies include the Yocto Project build system.

```bitbake
# conf/layer.conf
BBPATH .= ":${LAYERDIR}"

BBFILES += "${LAYERDIR}/recipes*/*/*.bb \
            ${LAYERDIR}/recipes*/*/*.bbappend"

BBFILE_COLLECTIONS += "raspberrypi"
BBFILE_PATTERN_raspberrypi := "^${LAYERDIR}/"
BBFILE_PRIORITY_raspberrypi = "9"

LAYERSERIES_COMPAT_raspberrypi = "whinlatter"
LAYERDEPENDS_raspberrypi = "core"

# Dynamic layer support for optional dependencies
BBFILES_DYNAMIC += " \
    openembedded-layer:${LAYERDIR}/dynamic-layers/openembedded-layer/*/*/*.bb \
    openembedded-layer:${LAYERDIR}/dynamic-layers/openembedded-layer/*/*/*.bbappend \
    qt5-layer:${LAYERDIR}/dynamic-layers/qt5-layer/*/*/*.bb \
    qt5-layer:${LAYERDIR}/dynamic-layers/qt5-layer/*/*/*.bbappend \
    multimedia-layer:${LAYERDIR}/dynamic-layers/multimedia-layer/*/*/*.bb \
    multimedia-layer:${LAYERDIR}/dynamic-layers/multimedia-layer/*/*/*.bbappend \
"

```

--------------------------------

### Enable Infrared Support (LIRC)

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Enables infrared support for LIRC by adding device tree overlays and kernel modules. Configures default GPIO pins for infrared reception and transmission, which can be customized.

```shell
ENABLE_IR = "1"
```

--------------------------------

### Enable Dispmanx Offline Compositing Support

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Enables support for dispmanx offline compositing, allowing the firmware to fall back to off-line compositing of Dispmanx elements when scene complexity is high. This is recommended for Wayland/Weston. Set DISPMANX_OFFLINE to '1' in local.conf.

```none
DISPMANX_OFFLINE = "1"
```

--------------------------------

### Enable I2C Support and Auto-load Modules

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Enables I2C support for device tree kernels and configures automatic loading of I2C kernel modules. Set ENABLE_I2C to '1' and use KERNEL_MODULE_AUTOLOAD:rpi to specify modules like 'i2c-dev' and 'i2c-bcm2708'.

```none
ENABLE_I2C = "1"
KERNEL_MODULE_AUTOLOAD:rpi += "i2c-dev i2c-bcm2708"
```

--------------------------------

### Python Package Recipe for Sense HAT

Source: https://context7.com/agherzan/meta-raspberrypi/llms.txt

BitBake recipe for the Python Sense HAT library, commonly used with Raspberry Pi. It specifies source URI, revision, build system, and runtime dependencies.

```bitbake
# dynamic-layers/meta-python/recipes-devtools/python/python3-sense-hat_2.2.0.bb
SUMMARY = "Python module for the Raspberry Pi Sense HAT"
HOMEPAGE = "https://github.com/astro-pi/python-sense-hat"
LICENSE = "BSD-3-Clause"

SRC_URI = "git://github.com/astro-pi/python-sense-hat.git;protocol=https;branch=master"
SRCREV = "a794c388d1e0c19391e41354e41c2e20fc3a8f81"

inherit setuptools3

RDEPENDS:${PN} += " 
    python3-numpy 
    python3-pillow 
    sense-hat-driver 
"

```

--------------------------------

### Enable KGDB over Console Support

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Adds the kgdb over console (kgdboc) parameter to the kernel command line, facilitating remote debugging. Set the ENABLE_KGDB variable to '1' in local.conf.

```none
ENABLE_KGDB = "1"
```

--------------------------------

### Kas Configuration for Raspberry Pi (YAML)

Source: https://context7.com/agherzan/meta-raspberrypi/llms.txt

This YAML file configures the kas build system for Raspberry Pi 4, specifying the machine, distribution, target image, and required Yocto layers. It also includes a local configuration header for package class settings.

```yaml
# kas-poky-rpi.yml
header:
  version: 8

machine: raspberrypi4
distro: poky
target:
  - core-image-base

repos:
  meta-raspberry:

  poky:
    url: https://git.yoctoproject.org/git/poky
    path: layers/poky
    branch: master
    layers:
      - meta
      - meta-poky
      - meta-yocto-bsp

  meta-openembedded:
    url: http://git.openembedded.org/meta-openembedded
    path: layers/meta-openembedded
    branch: master
    layers:
      - meta-oe
      - meta-python

local_conf_header:
  standard: |
    CONF_VERSION = "2"
    PACKAGE_CLASSES = "package_rpm"

```

--------------------------------

### Build Initramfs Image Configuration

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Settings for building an initramfs image. This involves configuring kernel variables like BLK_DEV_INITRD, INITRAMFS_SOURCE, and RD_GZIP, as well as Yocto variables such as INITRAMFS_IMAGE, INITRAMFS_IMAGE_BUNDLE, BOOT_SPACE, INITRAMFS_MAXSIZE, and IMAGE_FSTYPES.

```none
kernel_configure_variable BLK_DEV_INITRD y
kernel_configure_variable INITRAMFS_SOURCE ""
kernel_configure_variable RD_GZIP y
INITRAMFS_IMAGE = "<name for your initramfs image>"
INITRAMFS_IMAGE_BUNDLE = "1"
BOOT_SPACE = "1073741"
INITRAMFS_MAXSIZE = "315400"
IMAGE_FSTYPES:pn-${INITRAMFS_IMAGE} = "${INITRAMFS_FSTYPES}"
```

--------------------------------

### Base Raspberry Pi Machine Configuration with Device Tree (BitBake)

Source: https://context7.com/agherzan/meta-raspberrypi/llms.txt

Provides common configuration for all Raspberry Pi machines, including image file system types, kernel device tree configurations, and optional device tree overlays. It also specifies general machine features like APM, USB host, keyboard, and graphics support. This file is included by specific machine configurations.

```bitbake
# conf/machine/include/rpi-base.inc
IMAGE_FSTYPES ?= "tar.bz2 ext3 wic.bz2 wic.bmap"
WKS_FILE ?= "sdimage-raspberrypi.wks"

KERNEL_DEVICETREE ??= " \
    ${RPI_KERNEL_DEVICETREE} \
    ${RPI_KERNEL_DEVICETREE_OVERLAYS} \
"

RPI_KERNEL_DEVICETREE_OVERLAYS ?= " \
    overlays/vc4-kms-v3d.dtbo \
    overlays/gpio-shutdown.dtbo \
    overlays/i2c-rtc.dtbo \
    overlays/mcp2515-can0.dtbo \
    overlays/uart0.dtbo \
    overlays/w1-gpio.dtbo \
"

MACHINE_FEATURES += "apm usbhost keyboard vfat ext2 screen touchscreen alsa bluetooth wifi sdio vc4graphics"
MACHINE_FEATURES_BACKFILL_CONSIDERED = "rtc"

IMAGE_BOOT_FILES ?= "${BOOTFILES_DIR_NAME}/* \
                 ${@make_dtb_boot_files(d)} \
                 ${RPI_EXTRA_IMAGE_BOOT_FILES} \
"

```

--------------------------------

### Enable Video Camera Support with V4L2 Drivers

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Enables support for the Raspberry Pi's video camera using V4L2 drivers. This requires Linux kernel version 3.12.4 or newer. The VIDEO_CAMERA variable should be set to '1' in local.conf.

```none
VIDEO_CAMERA = "1"
```

--------------------------------

### Disable Splash Screen (Yocto/BitBake)

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Disables the default rainbow splash screen that appears after the GPU firmware loads during boot. Set DISABLE_SPLASH to "1" in local.conf to prevent this visual indicator.

```bitbake
DISABLE_SPLASH = "1"
```

--------------------------------

### Enable GPIO Shutdown

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Activates GPIO shutdown functionality, adding the corresponding device tree overlay and kernel module. It handles initialization with System V init or Systemd. Allows customization of the GPIO pin used for shutdown, especially when conflicts arise with I2C or PiTFT.

```shell
ENABLE_GPIO_SHUTDOWN = "1"
GPIO_SHUTDOWN_PIN = "25"
```

--------------------------------

### Configure Compressed Deployed Files (Yocto/BitBake)

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Allows users to specify the desired file system types for compressed deployed images. This is achieved by overwriting the IMAGE_FSTYPES variable in local.conf. Users can choose from various compression formats and file system types like tar.bz2, ext3.xz, or ext4.

```bitbake
IMAGE_FSTYPES = "tar.bz2 ext3.xz"
SDIMG_ROOTFS_TYPE = "ext3.xz"
```

--------------------------------

### Custom Raspberry Pi Test Image Recipe (BitBake)

Source: https://context7.com/agherzan/meta-raspberrypi/llms.txt

This BitBake recipe defines a custom image for Raspberry Pi, inheriting from 'core-image-base' and appending a Raspberry Pi-specific package group. It ensures compatibility with Raspberry Pi machines.

```bitbake
# recipes-core/images/rpi-test-image.bb
include recipes-core/images/core-image-base.bb

COMPATIBLE_MACHINE = "^rpi$"
IMAGE_INSTALL:append = " packagegroup-rpi-test"

```

--------------------------------

### Enable One-Wire Interface

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Enables the one-wire communication bus, typically used for connecting sensors. The default GPIO pin is 4, but it can be configured. After enabling, devices can be listed using a system command.

```shell
ENABLE_W1 = "1"
ls /sys/bus/w1/devices/
```

--------------------------------

### Raspberry Pi Configuration Variables

Source: https://context7.com/agherzan/meta-raspberrypi/llms.txt

Common configuration variables for customizing Raspberry Pi hardware settings in a Yocto Project build. These include GPU memory, peripheral enablement, display settings, and more.

```config
# GPU Memory allocation (in MB)
GPU_MEM = "256"
GPU_MEM_1024 = "512"

# Enable peripheral interfaces
ENABLE_UART = "1"
ENABLE_I2C = "1"
ENABLE_SPI_BUS = "1"

# Camera module support
RASPBERRYPI_CAMERA_V2 = "1"
RASPBERRYPI_CAMERA_V3 = "1"

# Display configuration
DISABLE_OVERSCAN = "1"
HDMI_FORCE_HOTPLUG = "1"
HDMI_GROUP = "2"
HDMI_MODE = "82"

# USB configuration
ENABLE_DWC2_PERIPHERAL = "1"

# CAN bus support
ENABLE_CAN = "1"
CAN_OSCILLATOR = "16000000"
CAN0_INTERRUPT_PIN = "25"

# GPIO shutdown
ENABLE_GPIO_SHUTDOWN = "1"
GPIO_SHUTDOWN_PIN = "3"

# One-Wire interface
ENABLE_W1 = "1"

# Custom config.txt additions
RPI_EXTRA_CONFIG = " 
    dtoverlay=gpio-shutdown,gpio_pin=3 
    dtoverlay=w1-gpio 
    hdmi_force_hotplug=1 
"

# U-Boot support
RPI_USE_U_BOOT = "1"

# Boot media (SD card or USB)
CMDLINE_ROOT_PARTITION = "/dev/sda2"
BOOT_MEDIA = "usb"

# Video codec licenses (purchased from Raspberry Pi)
KEY_DECODE_MPG2 = "0x12345678"
KEY_DECODE_WVC1 = "0xabcdefgh"

# Disable VC4 graphics (fallback to userland - 32-bit only)
DISABLE_VC4GRAPHICS = "1"

# Image compression
IMAGE_FSTYPES = "tar.bz2 ext3.xz wic.bz2"
SDIMG_ROOTFS_TYPE = "ext3.xz"

```

--------------------------------

### Enable SPI Bus Support

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Enables the SPI bus on the Raspberry Pi when using device tree kernels. Set the ENABLE_SPI_BUS variable to '1' in local.conf.

```none
ENABLE_SPI_BUS = "1"
```

--------------------------------

### Raspberry Pi 4 Machine Configuration (BitBake)

Source: https://context7.com/agherzan/meta-raspberrypi/llms.txt

Defines hardware-specific settings for the RaspberryPi 4 in 32-bit mode. It sets the default tune, includes base Raspberry Pi configurations, and specifies firmware, kernel image, bootloader, serial console, and device tree configurations. Dependencies include BitBake and ARM architecture tune files.

```bitbake
# conf/machine/raspberrypi4.conf
#@TYPE: Machine
#@NAME: RaspberryPi 4 Development Board (32bit)
#@DESCRIPTION: Machine configuration for the RaspberryPi 4 in 32 bit mode

DEFAULTTUNE ?= "cortexa7thf-neon-vfpv4"
require conf/machine/include/arm/armv7a/tune-cortexa7.inc
include conf/machine/include/rpi-base.inc

MACHINE_FEATURES += "pci"
MACHINE_EXTRA_RRECOMMENDS += "
    linux-firmware-rpidistro-bcm43455 \
    bluez-firmware-rpidistro-bcm4345c0-hcd \
    linux-firmware-rpidistro-bcm43456 \
    bluez-firmware-rpidistro-bcm4345c5-hcd \
"

SDIMG_KERNELIMAGE ?= "kernel7l.img"
UBOOT_MACHINE = "rpi_4_32b_config"
SERIAL_CONSOLES ?= "115200;ttyS0"
VC4DTBO ?= "vc4-kms-v3d"
ARMSTUB ?= "armstub7.bin"

```

--------------------------------

### Configure GPU Memory (Yocto/BitBake)

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Sets the amount of memory allocated to the GPU on Raspberry Pi devices. Variables like GPU_MEM, GPU_MEM_256, GPU_MEM_512, and GPU_MEM_1024 allow fine-grained control based on the Raspberry Pi model and desired memory split. Minimum values and overrides are detailed in the documentation.

```bitbake
# Example: Set GPU memory to 128MB
GPU_MEM = "128"

# Example: Specific GPU memory for 512MB RPi
GPU_MEM_512 = "384"
```

--------------------------------

### Disable Overscan (Yocto/BitBake)

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Removes the black border (overscan) that the GPU typically adds around the video output. This setting is controlled by the DISABLE_OVERSCAN variable in local.conf, allowing for full-screen display on compatible monitors.

```bitbake
DISABLE_OVERSCAN = "1"
```

--------------------------------

### Disable VC4 Graphics (Yocto/BitBake)

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Disables the default VC4 graphics driver, causing the build to fall back to using 'userland'. This option is controlled by the DISABLE_VC4GRAPHICS variable. Caution is advised when using this on 64-bit Raspberry Pi machines due to potential build breakage.

```bitbake
DISABLE_VC4GRAPHICS = "1"
```

--------------------------------

### Disable Raspberry Pi Boot Logo

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Disables the Raspberry Pi boot logo displayed during the system startup process. Set the DISABLE_RPI_BOOT_LOGO variable to '1' in local.conf.

```none
DISABLE_RPI_BOOT_LOGO = "1"
```

--------------------------------

### Force HDMI Output to 720p in CEA Mode

Source: https://github.com/agherzan/meta-raspberrypi/blob/master/docs/extra-build-config.md

Configures the Raspberry Pi to force HDMI output to a specific mode (720p in CEA mode). This is done by setting HDMI_GROUP and HDMI_MODE variables. These settings are typically used in local.conf files.

```none
HDMI_GROUP = "1"
HDMI_MODE = "4"
```