The Yocto Project provides an integrated environment to develop and debug custom embedded Linux systems, similar to commercial embedded Linux development environments.
In this talk, we will introduce the different parts and lexicon of the Yocto Project: poky, OpenEmbedded-core, bitbake, layers, recipes, machine, distro, etc. Different “How to” will be detailed: how to configure it, build an image from layers, create recipes and add a custom machine.
Throughout the talk, many good practices will be detailed. Thanks to that, the audience will have a good overview of Yocto Project and will know how to start using it in an effective way.
This talk is intended for developers or technical people who want to work/start with Yocto/Openembedded. Good practices are important when working with Yocto Project and will be detailed in this presentation.
No particular knowledge is required to attend this talk.
Mylène Josserand, Free Electrons
1. Embedded Recipes Conference - 2017
Introduction to the Yocto Project /
OpenEmbedded-core
Mylène Josserand
Free Electrons
mylene@free-electrons.com
Embedded Linux
Experts
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 1/35
2. Mylène Josserand
▶ Embedded Linux engineer at Free Electrons
since 2016
▶ Embedded Linux expertise
▶ Development, consulting and training around
the Yocto Project
▶ One of the authors of Free Electrons’ Yocto
Project / OpenEmbedded training
materials.
▶ Kernel contributor: audio driver, touchscreen,
RTC and more to come!
Embedded Linux
Experts
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 2/35
3. Introduction
▶ In this talk, we will:
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 3/35
4. Introduction
▶ In this talk, we will:
▶ Understand why we should use a build system
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 3/35
5. Introduction
▶ In this talk, we will:
▶ Understand why we should use a build system
▶ How the Yocto Project / OpenEmbedded core are structured
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 3/35
6. Introduction
▶ In this talk, we will:
▶ Understand why we should use a build system
▶ How the Yocto Project / OpenEmbedded core are structured
▶ How we can use it
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 3/35
7. Introduction
▶ In this talk, we will:
▶ Understand why we should use a build system
▶ How the Yocto Project / OpenEmbedded core are structured
▶ How we can use it
▶ How we can update it to fit our needs
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 3/35
8. Introduction
▶ In this talk, we will:
▶ Understand why we should use a build system
▶ How the Yocto Project / OpenEmbedded core are structured
▶ How we can use it
▶ How we can update it to fit our needs
▶ Give some good practices to start using the Yocto Project correctly
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 3/35
9. Introduction
▶ In this talk, we will:
▶ Understand why we should use a build system
▶ How the Yocto Project / OpenEmbedded core are structured
▶ How we can use it
▶ How we can update it to fit our needs
▶ Give some good practices to start using the Yocto Project correctly
▶ Allows to customize many things: it is easy to do things the wrong way
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 3/35
10. Introduction
▶ In this talk, we will:
▶ Understand why we should use a build system
▶ How the Yocto Project / OpenEmbedded core are structured
▶ How we can use it
▶ How we can update it to fit our needs
▶ Give some good practices to start using the Yocto Project correctly
▶ Allows to customize many things: it is easy to do things the wrong way
▶ When you see a ✓, it means it is a good practice!
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 3/35
11. Why use a build system?
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 4/35
12. Why use a build system?
▶ In the Embedded world, we have many constraints
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 4/35
13. Why use a build system?
▶ In the Embedded world, we have many constraints
▶ Nice to reduce the system to a minimal one + add our custom application
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 4/35
14. Why use a build system?
▶ In the Embedded world, we have many constraints
▶ Nice to reduce the system to a minimal one + add our custom application
▶ A build system will automate the creation of the system in a reproducible way
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 4/35
15. Why use a build system?
▶ In the Embedded world, we have many constraints
▶ Nice to reduce the system to a minimal one + add our custom application
▶ A build system will automate the creation of the system in a reproducible way
▶ Integration means packaging applications to create a final image
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 4/35
16. System integration: several possibilities
▶ Building everything manually:
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 5/35
17. System integration: several possibilities
▶ Building everything manually:
⊕
Full flexibility
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 5/35
18. System integration: several possibilities
▶ Building everything manually:
⊕
Full flexibility⊗
Dependency hell
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 5/35
19. System integration: several possibilities
▶ Building everything manually:
⊕
Full flexibility⊗
Dependency hell⊗
Lack of reproducibility
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 5/35
20. System integration: several possibilities
▶ Building everything manually:
⊕
Full flexibility⊗
Dependency hell⊗
Lack of reproducibility
▶ Binary distribution (Debian, Ubuntu, Fedora, etc):
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 5/35
21. System integration: several possibilities
▶ Building everything manually:
⊕
Full flexibility⊗
Dependency hell⊗
Lack of reproducibility
▶ Binary distribution (Debian, Ubuntu, Fedora, etc):
⊕
Easy to create and extend
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 5/35
22. System integration: several possibilities
▶ Building everything manually:
⊕
Full flexibility⊗
Dependency hell⊗
Lack of reproducibility
▶ Binary distribution (Debian, Ubuntu, Fedora, etc):
⊕
Easy to create and extend⊗
Hard to customize and optimize (boot time, size)
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 5/35
23. System integration: several possibilities
▶ Building everything manually:
⊕
Full flexibility⊗
Dependency hell⊗
Lack of reproducibility
▶ Binary distribution (Debian, Ubuntu, Fedora, etc):
⊕
Easy to create and extend⊗
Hard to customize and optimize (boot time, size)⊗
Hard to rebuild from source
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 5/35
24. System integration: several possibilities
▶ Building everything manually:
⊕
Full flexibility⊗
Dependency hell⊗
Lack of reproducibility
▶ Binary distribution (Debian, Ubuntu, Fedora, etc):
⊕
Easy to create and extend⊗
Hard to customize and optimize (boot time, size)⊗
Hard to rebuild from source⊗
Native-compilation
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 5/35
25. System integration: several possibilities
▶ Building everything manually:
⊕
Full flexibility⊗
Dependency hell⊗
Lack of reproducibility
▶ Binary distribution (Debian, Ubuntu, Fedora, etc):
⊕
Easy to create and extend⊗
Hard to customize and optimize (boot time, size)⊗
Hard to rebuild from source⊗
Native-compilation⊗
Not available for all architectures
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 5/35
26. System integration: several possibilities
▶ Building everything manually:
⊕
Full flexibility⊗
Dependency hell⊗
Lack of reproducibility
▶ Binary distribution (Debian, Ubuntu, Fedora, etc):
⊕
Easy to create and extend⊗
Hard to customize and optimize (boot time, size)⊗
Hard to rebuild from source⊗
Native-compilation⊗
Not available for all architectures
▶ Build systems (Buildroot, the Yocto Project, etc):
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 5/35
27. System integration: several possibilities
▶ Building everything manually:
⊕
Full flexibility⊗
Dependency hell⊗
Lack of reproducibility
▶ Binary distribution (Debian, Ubuntu, Fedora, etc):
⊕
Easy to create and extend⊗
Hard to customize and optimize (boot time, size)⊗
Hard to rebuild from source⊗
Native-compilation⊗
Not available for all architectures
▶ Build systems (Buildroot, the Yocto Project, etc):
⊗
Not as easy as a binary distribution
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 5/35
28. System integration: several possibilities
▶ Building everything manually:
⊕
Full flexibility⊗
Dependency hell⊗
Lack of reproducibility
▶ Binary distribution (Debian, Ubuntu, Fedora, etc):
⊕
Easy to create and extend⊗
Hard to customize and optimize (boot time, size)⊗
Hard to rebuild from source⊗
Native-compilation⊗
Not available for all architectures
▶ Build systems (Buildroot, the Yocto Project, etc):
⊗
Not as easy as a binary distribution⊕
Nearly full flexibility
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 5/35
29. System integration: several possibilities
▶ Building everything manually:
⊕
Full flexibility⊗
Dependency hell⊗
Lack of reproducibility
▶ Binary distribution (Debian, Ubuntu, Fedora, etc):
⊕
Easy to create and extend⊗
Hard to customize and optimize (boot time, size)⊗
Hard to rebuild from source⊗
Native-compilation⊗
Not available for all architectures
▶ Build systems (Buildroot, the Yocto Project, etc):
⊗
Not as easy as a binary distribution⊕
Nearly full flexibility⊕
Built from source: customization and optimization are easy
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 5/35
30. System integration: several possibilities
▶ Building everything manually:
⊕
Full flexibility⊗
Dependency hell⊗
Lack of reproducibility
▶ Binary distribution (Debian, Ubuntu, Fedora, etc):
⊕
Easy to create and extend⊗
Hard to customize and optimize (boot time, size)⊗
Hard to rebuild from source⊗
Native-compilation⊗
Not available for all architectures
▶ Build systems (Buildroot, the Yocto Project, etc):
⊗
Not as easy as a binary distribution⊕
Nearly full flexibility⊕
Built from source: customization and optimization are easy⊕
Fully reproducible
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 5/35
31. System integration: several possibilities
▶ Building everything manually:
⊕
Full flexibility⊗
Dependency hell⊗
Lack of reproducibility
▶ Binary distribution (Debian, Ubuntu, Fedora, etc):
⊕
Easy to create and extend⊗
Hard to customize and optimize (boot time, size)⊗
Hard to rebuild from source⊗
Native-compilation⊗
Not available for all architectures
▶ Build systems (Buildroot, the Yocto Project, etc):
⊗
Not as easy as a binary distribution⊕
Nearly full flexibility⊕
Built from source: customization and optimization are easy⊕
Fully reproducible⊕
Cross-compilation
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 5/35
32. Representation in the Yocto Project
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 6/35
33. Representation in the Yocto Project
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 6/35
34. Representation in the Yocto Project
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 6/35
35. Representation in the Yocto Project
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 6/35
36. Representation in the Yocto Project
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 6/35
37. Representation in the Yocto Project
▶ Common tasks defined in OpenEmbedded core
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 6/35
38. Representation in the Yocto Project
▶ Common tasks defined in OpenEmbedded core
▶ Many recipes availables for many applications: organized in layers
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 6/35
39. Representation in the Yocto Project
▶ Common tasks defined in OpenEmbedded core
▶ Many recipes availables for many applications: organized in layers
▶ Allow to build custom embedded Linux-based systems
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 6/35
40. Representation in the Yocto Project
▶ Common tasks defined in OpenEmbedded core
▶ Many recipes availables for many applications: organized in layers
▶ Allow to build custom embedded Linux-based systems
⇒ This is the aim of the Yocto Project
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 6/35
41. OpenEmbedded core & Poky
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 7/35
42. OpenEmbedded core & Poky
▶ Co-maintained by the Yocto
Project and OpenEmbedded
Project
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 7/35
43. OpenEmbedded core & Poky
▶ Co-maintained by the Yocto
Project and OpenEmbedded
Project
▶ Set of base layer with recipes
and classes
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 7/35
44. OpenEmbedded core & Poky
▶ Co-maintained by the Yocto
Project and OpenEmbedded
Project
▶ Set of base layer with recipes
and classes
▶ It is the core of all the magic
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 7/35
45. OpenEmbedded core & Poky
▶ Co-maintained by the Yocto
Project and OpenEmbedded
Project
▶ Set of base layer with recipes
and classes
▶ It is the core of all the magic
▶ It supports the ARM, MIPS (32
and 64 bits), PowerPC and x86
(32 and 64 bits) architectures +
QEMU
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 7/35
46. OpenEmbedded core & Poky
▶ Co-maintained by the Yocto
Project and OpenEmbedded
Project
▶ Set of base layer with recipes
and classes
▶ It is the core of all the magic
▶ It supports the ARM, MIPS (32
and 64 bits), PowerPC and x86
(32 and 64 bits) architectures +
QEMU
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 7/35
47. OpenEmbedded core & Poky
▶ Co-maintained by the Yocto
Project and OpenEmbedded
Project
▶ Set of base layer with recipes
and classes
▶ It is the core of all the magic
▶ It supports the ARM, MIPS (32
and 64 bits), PowerPC and x86
(32 and 64 bits) architectures +
QEMU
▶ Reference distribution of the Yocto Project
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 7/35
48. OpenEmbedded core & Poky
▶ Co-maintained by the Yocto
Project and OpenEmbedded
Project
▶ Set of base layer with recipes
and classes
▶ It is the core of all the magic
▶ It supports the ARM, MIPS (32
and 64 bits), PowerPC and x86
(32 and 64 bits) architectures +
QEMU
▶ Reference distribution of the Yocto Project
▶ Contains everything you need to start a
project:
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 7/35
49. OpenEmbedded core & Poky
▶ Co-maintained by the Yocto
Project and OpenEmbedded
Project
▶ Set of base layer with recipes
and classes
▶ It is the core of all the magic
▶ It supports the ARM, MIPS (32
and 64 bits), PowerPC and x86
(32 and 64 bits) architectures +
QEMU
▶ Reference distribution of the Yocto Project
▶ Contains everything you need to start a
project:
▶ OpenEmbedded-core
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 7/35
50. OpenEmbedded core & Poky
▶ Co-maintained by the Yocto
Project and OpenEmbedded
Project
▶ Set of base layer with recipes
and classes
▶ It is the core of all the magic
▶ It supports the ARM, MIPS (32
and 64 bits), PowerPC and x86
(32 and 64 bits) architectures +
QEMU
▶ Reference distribution of the Yocto Project
▶ Contains everything you need to start a
project:
▶ OpenEmbedded-core
▶ Bitbake
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 7/35
51. OpenEmbedded core & Poky
▶ Co-maintained by the Yocto
Project and OpenEmbedded
Project
▶ Set of base layer with recipes
and classes
▶ It is the core of all the magic
▶ It supports the ARM, MIPS (32
and 64 bits), PowerPC and x86
(32 and 64 bits) architectures +
QEMU
▶ Reference distribution of the Yocto Project
▶ Contains everything you need to start a
project:
▶ OpenEmbedded-core
▶ Bitbake
▶ Additional layers
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 7/35
52. OpenEmbedded core & Poky
▶ Co-maintained by the Yocto
Project and OpenEmbedded
Project
▶ Set of base layer with recipes
and classes
▶ It is the core of all the magic
▶ It supports the ARM, MIPS (32
and 64 bits), PowerPC and x86
(32 and 64 bits) architectures +
QEMU
▶ Reference distribution of the Yocto Project
▶ Contains everything you need to start a
project:
▶ OpenEmbedded-core
▶ Bitbake
▶ Additional layers
▶ Also contains some useful tools to ease
recipes and layers’ creation
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 7/35
53. The Yocto Project / OpenEmbedded Core / Poky
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 8/35
54. Workflow - General
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 9/35
55. Workflow - General
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 9/35
56. Workflow - General
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 9/35
57. Workflow - Users/Developers actions
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 10/35
58. Workflow - 1. Download
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 11/35
59. Workflow - 1. Download
▶ Find which version you want to use:
Figure: https://wiki.yoctoproject.org/wiki/Releases
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 11/35
60. Workflow - 1. Download
▶ Find which version you want to use:
Figure: https://wiki.yoctoproject.org/wiki/Releases
▶ Support level: Development, Stable, Community
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 11/35
61. Workflow - 1. Download
▶ Find which version you want to use:
Figure: https://wiki.yoctoproject.org/wiki/Releases
▶ Support level: Development, Stable, Community
▶ A codename corresponds to a Poky and Bitbake versions
Pyro = Yocto Project v2.3 → Poky v17.0 & Bitbake v1.34
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 11/35
62. Workflow - 1. Download
▶ Find which version you want to use:
Figure: https://wiki.yoctoproject.org/wiki/Releases
▶ Support level: Development, Stable, Community
▶ A codename corresponds to a Poky and Bitbake versions
Pyro = Yocto Project v2.3 → Poky v17.0 & Bitbake v1.34
▶ How to download:
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 11/35
63. Workflow - 1. Download
▶ Find which version you want to use:
Figure: https://wiki.yoctoproject.org/wiki/Releases
▶ Support level: Development, Stable, Community
▶ A codename corresponds to a Poky and Bitbake versions
Pyro = Yocto Project v2.3 → Poky v17.0 & Bitbake v1.34
▶ How to download:
git clone -b pyro git://git.yoctoproject.org/poky.git
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 11/35
64. Workflow - 1. Download
▶ Layers are sets of recipes, matching a common purpose.
To simplify things, they are just folders
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 12/35
65. Workflow - 1. Download
▶ Layers are sets of recipes, matching a common purpose.
To simplify things, they are just folders
▶ Look at existing layers
Figure: http://layers.openembedded.org/layerindex/
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 12/35
66. Workflow - 1. Download
▶ Layers are sets of recipes, matching a common purpose.
To simplify things, they are just folders
▶ Look at existing layers
Figure: http://layers.openembedded.org/layerindex/
▶ Download all other layers on same branch than Poky: Pyro
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 12/35
67. Workflow - 1. Download
▶ Layers are sets of recipes, matching a common purpose.
To simplify things, they are just folders
▶ Look at existing layers
Figure: http://layers.openembedded.org/layerindex/
▶ Download all other layers on same branch than Poky: Pyro
✓ Use existing layers before creating a new one ⇒ saves you time
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 12/35
68. Workflow - 1. Download
▶ Layers are sets of recipes, matching a common purpose.
To simplify things, they are just folders
▶ Look at existing layers
Figure: http://layers.openembedded.org/layerindex/
▶ Download all other layers on same branch than Poky: Pyro
✓ Use existing layers before creating a new one ⇒ saves you time
✓ DO NOT EDIT POKY/UPSTREAM LAYERS ⇒ complicates updates
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 12/35
69. Workflow - 2. Configure the build
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 13/35
70. Workflow - 2. Configure the build
▶ A script with all variables needed by Bitbake must be sourced:
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 13/35
71. Workflow - 2. Configure the build
▶ A script with all variables needed by Bitbake must be sourced:
source oe-init-build-env
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 13/35
72. Workflow - 2. Configure the build
▶ A script with all variables needed by Bitbake must be sourced:
source oe-init-build-env
▶ Will move you in a build folder
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 13/35
73. Workflow - 2. Configure the build
▶ A script with all variables needed by Bitbake must be sourced:
source oe-init-build-env
▶ Will move you in a build folder
▶ Now, can run any commands
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 13/35
74. Workflow - 2. Configure the build
▶ A script with all variables needed by Bitbake must be sourced:
source oe-init-build-env
▶ Will move you in a build folder
▶ Now, can run any commands
▶ All the local configurations are in the conf folder
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 13/35
75. Workflow - 2. Configure the build
▶ A script with all variables needed by Bitbake must be sourced:
source oe-init-build-env
▶ Will move you in a build folder
▶ Now, can run any commands
▶ All the local configurations are in the conf folder
build/
|-- conf
|-- bblayers.conf
|-- local.conf
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 13/35
76. Workflow - 2. Configure the build
▶ A script with all variables needed by Bitbake must be sourced:
source oe-init-build-env
▶ Will move you in a build folder
▶ Now, can run any commands
▶ All the local configurations are in the conf folder
build/
|-- conf
|-- bblayers.conf
|-- local.conf
▶ Edit your bblayers.conf with possible additional layers:
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 13/35
77. Workflow - 2. Configure the build
▶ A script with all variables needed by Bitbake must be sourced:
source oe-init-build-env
▶ Will move you in a build folder
▶ Now, can run any commands
▶ All the local configurations are in the conf folder
build/
|-- conf
|-- bblayers.conf
|-- local.conf
▶ Edit your bblayers.conf with possible additional layers:
BBLAYERS ?= "
/home/mylene/yocto/poky/meta
/home/mylene/yocto/poky/meta-poky
/home/mylene/yocto/poky/meta-yocto-bsp
/home/mylene/yocto/meta-freescale
/home/mylene/yocto/meta-qt5
"
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78. Workflow - 2. Configure the build
▶ Edit local.conf with your MACHINE and your DISTRO
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 14/35
79. Workflow - 2. Configure the build
▶ Edit local.conf with your MACHINE and your DISTRO
▶ MACHINE: Describes your hardware. Can find it under specific layers: BSP layers.
Look at conf/machine/ folders
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 14/35
80. Workflow - 2. Configure the build
▶ Edit local.conf with your MACHINE and your DISTRO
▶ MACHINE: Describes your hardware. Can find it under specific layers: BSP layers.
Look at conf/machine/ folders
▶ poky: beaglebone, x86, x86-64
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 14/35
81. Workflow - 2. Configure the build
▶ Edit local.conf with your MACHINE and your DISTRO
▶ MACHINE: Describes your hardware. Can find it under specific layers: BSP layers.
Look at conf/machine/ folders
▶ poky: beaglebone, x86, x86-64
▶ meta-ti: beagleboard, pandaboard, ...
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 14/35
82. Workflow - 2. Configure the build
▶ Edit local.conf with your MACHINE and your DISTRO
▶ MACHINE: Describes your hardware. Can find it under specific layers: BSP layers.
Look at conf/machine/ folders
▶ poky: beaglebone, x86, x86-64
▶ meta-ti: beagleboard, pandaboard, ...
▶ meta-fsl-arm: imx23, imx28, imx6, imx7, ...
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 14/35
83. Workflow - 2. Configure the build
▶ Edit local.conf with your MACHINE and your DISTRO
▶ MACHINE: Describes your hardware. Can find it under specific layers: BSP layers.
Look at conf/machine/ folders
▶ poky: beaglebone, x86, x86-64
▶ meta-ti: beagleboard, pandaboard, ...
▶ meta-fsl-arm: imx23, imx28, imx6, imx7, ...
▶ meta-atmel: at91*, sama5d*, ...
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 14/35
84. Workflow - 2. Configure the build
▶ Edit local.conf with your MACHINE and your DISTRO
▶ MACHINE: Describes your hardware. Can find it under specific layers: BSP layers.
Look at conf/machine/ folders
▶ poky: beaglebone, x86, x86-64
▶ meta-ti: beagleboard, pandaboard, ...
▶ meta-fsl-arm: imx23, imx28, imx6, imx7, ...
▶ meta-atmel: at91*, sama5d*, ...
▶ DISTRO: Represents the top-level configuration that will apply to every build. It
will include tools needed to use your hardware: compiler, libC, etc + some specific
variables Look at conf/distro/ folders
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 14/35
85. Workflow - 2. Configure the build
▶ Edit local.conf with your MACHINE and your DISTRO
▶ MACHINE: Describes your hardware. Can find it under specific layers: BSP layers.
Look at conf/machine/ folders
▶ poky: beaglebone, x86, x86-64
▶ meta-ti: beagleboard, pandaboard, ...
▶ meta-fsl-arm: imx23, imx28, imx6, imx7, ...
▶ meta-atmel: at91*, sama5d*, ...
▶ DISTRO: Represents the top-level configuration that will apply to every build. It
will include tools needed to use your hardware: compiler, libC, etc + some specific
variables Look at conf/distro/ folders
▶ poky: poky, poky-tiny, ...
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 14/35
86. Workflow - 2. Configure the build
▶ Edit local.conf with your MACHINE and your DISTRO
▶ MACHINE: Describes your hardware. Can find it under specific layers: BSP layers.
Look at conf/machine/ folders
▶ poky: beaglebone, x86, x86-64
▶ meta-ti: beagleboard, pandaboard, ...
▶ meta-fsl-arm: imx23, imx28, imx6, imx7, ...
▶ meta-atmel: at91*, sama5d*, ...
▶ DISTRO: Represents the top-level configuration that will apply to every build. It
will include tools needed to use your hardware: compiler, libC, etc + some specific
variables Look at conf/distro/ folders
▶ poky: poky, poky-tiny, ...
▶ meta-angstrom: angstrom
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 14/35
87. Workflow - 2. Configure the build
▶ Edit local.conf with your MACHINE and your DISTRO
▶ MACHINE: Describes your hardware. Can find it under specific layers: BSP layers.
Look at conf/machine/ folders
▶ poky: beaglebone, x86, x86-64
▶ meta-ti: beagleboard, pandaboard, ...
▶ meta-fsl-arm: imx23, imx28, imx6, imx7, ...
▶ meta-atmel: at91*, sama5d*, ...
▶ DISTRO: Represents the top-level configuration that will apply to every build. It
will include tools needed to use your hardware: compiler, libC, etc + some specific
variables Look at conf/distro/ folders
▶ poky: poky, poky-tiny, ...
▶ meta-angstrom: angstrom
▶ Noticed that local.conf ⇒ only for the local workstation.
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 14/35
88. Workflow - 2. Configure the build
▶ Edit local.conf with your MACHINE and your DISTRO
▶ MACHINE: Describes your hardware. Can find it under specific layers: BSP layers.
Look at conf/machine/ folders
▶ poky: beaglebone, x86, x86-64
▶ meta-ti: beagleboard, pandaboard, ...
▶ meta-fsl-arm: imx23, imx28, imx6, imx7, ...
▶ meta-atmel: at91*, sama5d*, ...
▶ DISTRO: Represents the top-level configuration that will apply to every build. It
will include tools needed to use your hardware: compiler, libC, etc + some specific
variables Look at conf/distro/ folders
▶ poky: poky, poky-tiny, ...
▶ meta-angstrom: angstrom
▶ Noticed that local.conf ⇒ only for the local workstation.
✓ Avoid changes directly in local.conf (or only for test purposes, except for some
variables such as MACHINE and DISTRO)
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89. Workflow - 3. Build an image
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90. Workflow - 3. Build an image
▶ What is an IMAGE?
⇒ Represents your root filesystem: all your applications, libraries, configuration
files, ... Will find it under recipes-*/images/
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 15/35
91. Workflow - 3. Build an image
▶ What is an IMAGE?
⇒ Represents your root filesystem: all your applications, libraries, configuration
files, ... Will find it under recipes-*/images/
▶ Common images already exist in Poky: core-image-minimal, core-image-base,
core-image-x11, ...
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 15/35
92. Workflow - 3. Build an image
▶ What is an IMAGE?
⇒ Represents your root filesystem: all your applications, libraries, configuration
files, ... Will find it under recipes-*/images/
▶ Common images already exist in Poky: core-image-minimal, core-image-base,
core-image-x11, ...
▶ Build an existing image:
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 15/35
93. Workflow - 3. Build an image
▶ What is an IMAGE?
⇒ Represents your root filesystem: all your applications, libraries, configuration
files, ... Will find it under recipes-*/images/
▶ Common images already exist in Poky: core-image-minimal, core-image-base,
core-image-x11, ...
▶ Build an existing image:
bitbake core-image-minimal
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94. MACHINE/DISTRO/IMAGE: a little reminder
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 16/35
95. MACHINE/DISTRO/IMAGE: a little reminder
▶ Machine: It represents your hardware
conf/machine/
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96. MACHINE/DISTRO/IMAGE: a little reminder
▶ Machine: It represents your hardware
conf/machine/
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97. MACHINE/DISTRO/IMAGE: a little reminder
▶ Machine: It represents your hardware
conf/machine/
▶ Distro: Represents the top-level
configuration that will apply on every
build
conf/distro/
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98. MACHINE/DISTRO/IMAGE: a little reminder
▶ Machine: It represents your hardware
conf/machine/
▶ Distro: Represents the top-level
configuration that will apply on every
build
conf/distro/
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 16/35
99. MACHINE/DISTRO/IMAGE: a little reminder
▶ Machine: It represents your hardware
conf/machine/
▶ Distro: Represents the top-level
configuration that will apply on every
build
conf/distro/
▶ Image: It represents your root
filesystem itself: all your applications,
libraries, configuration’s files, etc
recipes-core/images
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 16/35
100. MACHINE/DISTRO/IMAGE: a little reminder
▶ Machine: It represents your hardware
conf/machine/
▶ Distro: Represents the top-level
configuration that will apply on every
build
conf/distro/
▶ Image: It represents your root
filesystem itself: all your applications,
libraries, configuration’s files, etc
recipes-core/images
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101. Workflow - Developer
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102. Workflow - 4. Create a layer
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103. Workflow - 4. Create a layer
▶ You may have custom hardware, need to update recipes from upstream layers,
integrate your own application, etc
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 18/35
104. Workflow - 4. Create a layer
▶ You may have custom hardware, need to update recipes from upstream layers,
integrate your own application, etc
▶ Already said before: DO NOT EDIT POKY/UPSTREAM LAYERS
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 18/35
105. Workflow - 4. Create a layer
▶ You may have custom hardware, need to update recipes from upstream layers,
integrate your own application, etc
▶ Already said before: DO NOT EDIT POKY/UPSTREAM LAYERS
▶ To be able to do that, we will create our own layer that will host all our
modifications/applications
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 18/35
106. Workflow - 4. Create a layer
▶ You may have custom hardware, need to update recipes from upstream layers,
integrate your own application, etc
▶ Already said before: DO NOT EDIT POKY/UPSTREAM LAYERS
▶ To be able to do that, we will create our own layer that will host all our
modifications/applications
▶ Poky provides a tool to create layers:
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 18/35
107. Workflow - 4. Create a layer
▶ You may have custom hardware, need to update recipes from upstream layers,
integrate your own application, etc
▶ Already said before: DO NOT EDIT POKY/UPSTREAM LAYERS
▶ To be able to do that, we will create our own layer that will host all our
modifications/applications
▶ Poky provides a tool to create layers:
yocto-layer create <layer_name> -o <dest_dir>
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 18/35
108. Workflow - 4. Create a layer
▶ You may have custom hardware, need to update recipes from upstream layers,
integrate your own application, etc
▶ Already said before: DO NOT EDIT POKY/UPSTREAM LAYERS
▶ To be able to do that, we will create our own layer that will host all our
modifications/applications
▶ Poky provides a tool to create layers:
yocto-layer create <layer_name> -o <dest_dir>
✓ The layer’s name must be meta-* (done automatically using yocto-layer tool)
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 18/35
109. Workflow - 4. Create a layer
▶ You may have custom hardware, need to update recipes from upstream layers,
integrate your own application, etc
▶ Already said before: DO NOT EDIT POKY/UPSTREAM LAYERS
▶ To be able to do that, we will create our own layer that will host all our
modifications/applications
▶ Poky provides a tool to create layers:
yocto-layer create <layer_name> -o <dest_dir>
✓ The layer’s name must be meta-* (done automatically using yocto-layer tool)
✓ Avoid uppercase and funny/long names
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 18/35
110. Workflow - 4. Create a layer
▶ You may have custom hardware, need to update recipes from upstream layers,
integrate your own application, etc
▶ Already said before: DO NOT EDIT POKY/UPSTREAM LAYERS
▶ To be able to do that, we will create our own layer that will host all our
modifications/applications
▶ Poky provides a tool to create layers:
yocto-layer create <layer_name> -o <dest_dir>
✓ The layer’s name must be meta-* (done automatically using yocto-layer tool)
✓ Avoid uppercase and funny/long names
✓ If you have different projects with common parts, try to create two layers
⇒ Can re-use some parts
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111. Workflow - 5. Create a recipe
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112. Workflow - 5. Create a recipe
▶ A recipe is a file describing tasks for an application to:
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 19/35
113. Workflow - 5. Create a recipe
▶ A recipe is a file describing tasks for an application to:
▶ retrieve its sources
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114. Workflow - 5. Create a recipe
▶ A recipe is a file describing tasks for an application to:
▶ retrieve its sources
▶ configure it
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115. Workflow - 5. Create a recipe
▶ A recipe is a file describing tasks for an application to:
▶ retrieve its sources
▶ configure it
▶ compile it
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116. Workflow - 5. Create a recipe
▶ A recipe is a file describing tasks for an application to:
▶ retrieve its sources
▶ configure it
▶ compile it
▶ install it
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 19/35
117. Workflow - 5. Create a recipe
▶ A recipe is a file describing tasks for an application to:
▶ retrieve its sources
▶ configure it
▶ compile it
▶ install it
▶ It handles all the dependencies for you.
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 19/35
118. Workflow - 5. Create a recipe
▶ A recipe is a file describing tasks for an application to:
▶ retrieve its sources
▶ configure it
▶ compile it
▶ install it
▶ It handles all the dependencies for you.
▶ Many common tasks are already defined by OpenEmbedded-core
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 19/35
119. Workflow - 5. Create a recipe
▶ A recipe is a file describing tasks for an application to:
▶ retrieve its sources
▶ configure it
▶ compile it
▶ install it
▶ It handles all the dependencies for you.
▶ Many common tasks are already defined by OpenEmbedded-core
▶ Organized in folders with the same purpose (recipes-core, recipes-bsp,
recipes-kernel, recipes-devtool, recipes-support, ...) and a sub-folder with the
application’s name
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120. Workflow - 5. Create a recipe
▶ To create a recipe, you have to create a .bb file. It is the format that bitbake
understands
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121. Workflow - 5. Create a recipe
▶ To create a recipe, you have to create a .bb file. It is the format that bitbake
understands
▶ The format of a recipe file name is <application-name>_<version>.bb
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 20/35
122. Workflow - 5. Create a recipe
▶ To create a recipe, you have to create a .bb file. It is the format that bitbake
understands
▶ The format of a recipe file name is <application-name>_<version>.bb
▶ A recipe can be divided in three parts:
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 20/35
123. Workflow - 5. Create a recipe
▶ To create a recipe, you have to create a .bb file. It is the format that bitbake
understands
▶ The format of a recipe file name is <application-name>_<version>.bb
▶ A recipe can be divided in three parts:
▶ The header: what/who. Description of the application
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 20/35
124. Workflow - 5. Create a recipe
▶ To create a recipe, you have to create a .bb file. It is the format that bitbake
understands
▶ The format of a recipe file name is <application-name>_<version>.bb
▶ A recipe can be divided in three parts:
▶ The header: what/who. Description of the application
▶ The sources: where. Can be tarballs, remote repository, ...
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 20/35
125. Workflow - 5. Create a recipe
▶ To create a recipe, you have to create a .bb file. It is the format that bitbake
understands
▶ The format of a recipe file name is <application-name>_<version>.bb
▶ A recipe can be divided in three parts:
▶ The header: what/who. Description of the application
▶ The sources: where. Can be tarballs, remote repository, ...
▶ The tasks: how. How to proceed with the application’s sources
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 20/35
126. Workflow - 5. Create a recipe
▶ To create a recipe, you have to create a .bb file. It is the format that bitbake
understands
▶ The format of a recipe file name is <application-name>_<version>.bb
▶ A recipe can be divided in three parts:
▶ The header: what/who. Description of the application
▶ The sources: where. Can be tarballs, remote repository, ...
▶ The tasks: how. How to proceed with the application’s sources
▶ Classes are available for tasks commonly used: kernel, CMake, autotools, ...
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131. Workflow - 5. Create a recipe
✓ Always use remote repositories to host your application sources
⇒ Makes development quicker + keep history
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132. Workflow - 5. Create a recipe
✓ Always use remote repositories to host your application sources
⇒ Makes development quicker + keep history
✓ Do not put application sources in your layer directly!
⇒ Application development ̸= Application Integration
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133. Workflow - 5. Create a recipe
✓ Always use remote repositories to host your application sources
⇒ Makes development quicker + keep history
✓ Do not put application sources in your layer directly!
⇒ Application development ̸= Application Integration
✓ Keep the same folder organization: recipes-core/recipes-bsp/recipes-devtools/...
⇒ Find recipes quicker
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 25/35
134. Workflow - 5. Create a recipe
✓ Always use remote repositories to host your application sources
⇒ Makes development quicker + keep history
✓ Do not put application sources in your layer directly!
⇒ Application development ̸= Application Integration
✓ Keep the same folder organization: recipes-core/recipes-bsp/recipes-devtools/...
⇒ Find recipes quicker
✓ Keep the headers / sources / tasks organization in the recipe
⇒ All the recipes have the same content organization
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 25/35
135. Workflow - 5. Create a recipe
✓ Always use remote repositories to host your application sources
⇒ Makes development quicker + keep history
✓ Do not put application sources in your layer directly!
⇒ Application development ̸= Application Integration
✓ Keep the same folder organization: recipes-core/recipes-bsp/recipes-devtools/...
⇒ Find recipes quicker
✓ Keep the headers / sources / tasks organization in the recipe
⇒ All the recipes have the same content organization
✓ Use/Create include files when possible
⇒ Can extend other versions easily
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 25/35
136. Workflow - 5. Create a recipe
✓ Always use remote repositories to host your application sources
⇒ Makes development quicker + keep history
✓ Do not put application sources in your layer directly!
⇒ Application development ̸= Application Integration
✓ Keep the same folder organization: recipes-core/recipes-bsp/recipes-devtools/...
⇒ Find recipes quicker
✓ Keep the headers / sources / tasks organization in the recipe
⇒ All the recipes have the same content organization
✓ Use/Create include files when possible
⇒ Can extend other versions easily
✓ Know how to compile the application manually before integrating it in a recipe
⇒ Saves you time
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137. Workflow - 6. Extend a recipe
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138. Workflow - 6. Extend a recipe
▶ It is a good practice not to modify recipes available in Poky.
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139. Workflow - 6. Extend a recipe
▶ It is a good practice not to modify recipes available in Poky.
▶ But it is sometimes useful to modify an existing recipe
Free Electrons - Embedded Linux, kernel, drivers - Development, consulting, training and support. http://free-electrons.com 26/35
140. Workflow - 6. Extend a recipe
▶ It is a good practice not to modify recipes available in Poky.
▶ But it is sometimes useful to modify an existing recipe
▶ The BitBake build engine allows to modify a recipe by extending it
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141. Workflow - 6. Extend a recipe
▶ It is a good practice not to modify recipes available in Poky.
▶ But it is sometimes useful to modify an existing recipe
▶ The BitBake build engine allows to modify a recipe by extending it
▶ The recipe extensions end in .bbappend
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142. Workflow - 6. Extend a recipe
▶ It is a good practice not to modify recipes available in Poky.
▶ But it is sometimes useful to modify an existing recipe
▶ The BitBake build engine allows to modify a recipe by extending it
▶ The recipe extensions end in .bbappend
▶ Appended files must have the same root name as the recipe they extend
example_0.1.bbappend applies to example_0.1.bb
⇒ version specific
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143. Workflow - 6. Extend a recipe
▶ It is a good practice not to modify recipes available in Poky.
▶ But it is sometimes useful to modify an existing recipe
▶ The BitBake build engine allows to modify a recipe by extending it
▶ The recipe extensions end in .bbappend
▶ Appended files must have the same root name as the recipe they extend
example_0.1.bbappend applies to example_0.1.bb
⇒ version specific
▶ If adding new files, you must prepend the FILESEXTRAPATHS variable with the
path to files’ directory.
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145. Workflow - 7. Create an image
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146. Workflow - 7. Create an image
▶ An image is the top level recipe and is used alongside the machine definition
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147. Workflow - 7. Create an image
▶ An image is the top level recipe and is used alongside the machine definition
▶ Whereas the machine describes the hardware used and its capabilities, the image
is architecture agnostic and defines how the root filesystem is built, with what
packages
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148. Workflow - 7. Create an image
▶ An image is the top level recipe and is used alongside the machine definition
▶ Whereas the machine describes the hardware used and its capabilities, the image
is architecture agnostic and defines how the root filesystem is built, with what
packages
▶ By default, several images are provided in Poky:
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149. Workflow - 7. Create an image
▶ An image is the top level recipe and is used alongside the machine definition
▶ Whereas the machine describes the hardware used and its capabilities, the image
is architecture agnostic and defines how the root filesystem is built, with what
packages
▶ By default, several images are provided in Poky:
▶ meta*/recipes*/images/*.bb
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150. Workflow - 7. Create an image
▶ An image is the top level recipe and is used alongside the machine definition
▶ Whereas the machine describes the hardware used and its capabilities, the image
is architecture agnostic and defines how the root filesystem is built, with what
packages
▶ By default, several images are provided in Poky:
▶ meta*/recipes*/images/*.bb
▶ An image is no more than a recipe
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151. Workflow - 7. Create an image
▶ An image is the top level recipe and is used alongside the machine definition
▶ Whereas the machine describes the hardware used and its capabilities, the image
is architecture agnostic and defines how the root filesystem is built, with what
packages
▶ By default, several images are provided in Poky:
▶ meta*/recipes*/images/*.bb
▶ An image is no more than a recipe
▶ To create an image, simply create a .bb in an images folder
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152. Workflow - 7. Create an image
▶ An image is the top level recipe and is used alongside the machine definition
▶ Whereas the machine describes the hardware used and its capabilities, the image
is architecture agnostic and defines how the root filesystem is built, with what
packages
▶ By default, several images are provided in Poky:
▶ meta*/recipes*/images/*.bb
▶ An image is no more than a recipe
▶ To create an image, simply create a .bb in an images folder
mkdir -p recipes-core/images/
touch recipes-core/images/core-image-fe.bb
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153. Workflow - 7. Create an image
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154. Workflow - 7. Create an image
▶ Some special configuration variables are used to describe an image:
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155. Workflow - 7. Create an image
▶ Some special configuration variables are used to describe an image:
IMAGE_INSTALL List of packages to install in the generated image
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156. Workflow - 7. Create an image
▶ Some special configuration variables are used to describe an image:
IMAGE_INSTALL List of packages to install in the generated image
IMAGE_FSTYPES List of formats the OpenEmbedded build system will use to
create images
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157. Workflow - 7. Create an image
▶ Some special configuration variables are used to describe an image:
IMAGE_INSTALL List of packages to install in the generated image
IMAGE_FSTYPES List of formats the OpenEmbedded build system will use to
create images
✓ Create a minimal image to include it in others
⇒ Allows to have a minimal rootfs
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158. Workflow - 7. Create an image
▶ Some special configuration variables are used to describe an image:
IMAGE_INSTALL List of packages to install in the generated image
IMAGE_FSTYPES List of formats the OpenEmbedded build system will use to
create images
✓ Create a minimal image to include it in others
⇒ Allows to have a minimal rootfs
✓ Create different images according to your needs: image-minimal, image-dev,
image-x11, image-qt5, etc
⇒ Install only what you really need for your board.
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159. Workflow - 7. Create an image
recipes-core/images/core-image-fe.bb
inherit core-image
DESCRIPTION = "A small image to boot a device, created for Embedded Recipes"
LICENSE = "MIT"
IMAGE_FSTYPES = "tar.bz2 ext4"
IMAGE_INSTALL = "packagegroup-core-boot
nmon
helloworld
"
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160. Workflow - 8. Create a machine
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161. Workflow - 8. Create a machine
▶ A machine describes your hardware
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162. Workflow - 8. Create a machine
▶ A machine describes your hardware
▶ Stored under meta-<bsp_name>/conf/machine/*.conf
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163. Workflow - 8. Create a machine
▶ A machine describes your hardware
▶ Stored under meta-<bsp_name>/conf/machine/*.conf
▶ The file name corresponds to the value set in the MACHINE variable
meta-ti/conf/machine/beaglebone.conf
MACHINE = "beaglebone"
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164. Workflow - 8. Create a machine
▶ A machine describes your hardware
▶ Stored under meta-<bsp_name>/conf/machine/*.conf
▶ The file name corresponds to the value set in the MACHINE variable
meta-ti/conf/machine/beaglebone.conf
MACHINE = "beaglebone"
▶ Contains configuration variables related to the architecture, to machine’s features
and to customize the kernel image or the filesystems used.
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165. Workflow - 8. Create a machine
▶ A machine describes your hardware
▶ Stored under meta-<bsp_name>/conf/machine/*.conf
▶ The file name corresponds to the value set in the MACHINE variable
meta-ti/conf/machine/beaglebone.conf
MACHINE = "beaglebone"
▶ Contains configuration variables related to the architecture, to machine’s features
and to customize the kernel image or the filesystems used.
TARGET_ARCH : The architecture of the device being built
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166. Workflow - 8. Create a machine
▶ A machine describes your hardware
▶ Stored under meta-<bsp_name>/conf/machine/*.conf
▶ The file name corresponds to the value set in the MACHINE variable
meta-ti/conf/machine/beaglebone.conf
MACHINE = "beaglebone"
▶ Contains configuration variables related to the architecture, to machine’s features
and to customize the kernel image or the filesystems used.
TARGET_ARCH : The architecture of the device being built
PREFERRED_PROVIDER_virtual/kernel : The kernel recipe to use
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167. Workflow - 8. Create a machine
▶ A machine describes your hardware
▶ Stored under meta-<bsp_name>/conf/machine/*.conf
▶ The file name corresponds to the value set in the MACHINE variable
meta-ti/conf/machine/beaglebone.conf
MACHINE = "beaglebone"
▶ Contains configuration variables related to the architecture, to machine’s features
and to customize the kernel image or the filesystems used.
TARGET_ARCH : The architecture of the device being built
PREFERRED_PROVIDER_virtual/kernel : The kernel recipe to use
SERIAL_CONSOLE : Speed and device for the serial console to attach. Passed
to the kernel as the console parameter, e.g. 115200 ttyS0
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168. Workflow - 8. Create a machine
▶ A machine describes your hardware
▶ Stored under meta-<bsp_name>/conf/machine/*.conf
▶ The file name corresponds to the value set in the MACHINE variable
meta-ti/conf/machine/beaglebone.conf
MACHINE = "beaglebone"
▶ Contains configuration variables related to the architecture, to machine’s features
and to customize the kernel image or the filesystems used.
TARGET_ARCH : The architecture of the device being built
PREFERRED_PROVIDER_virtual/kernel : The kernel recipe to use
SERIAL_CONSOLE : Speed and device for the serial console to attach. Passed
to the kernel as the console parameter, e.g. 115200 ttyS0
KERNEL_IMAGETYPE : The type of kernel image to build, e.g. zImage
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169. Workflow - 8. Create a machine
▶ A machine describes your hardware
▶ Stored under meta-<bsp_name>/conf/machine/*.conf
▶ The file name corresponds to the value set in the MACHINE variable
meta-ti/conf/machine/beaglebone.conf
MACHINE = "beaglebone"
▶ Contains configuration variables related to the architecture, to machine’s features
and to customize the kernel image or the filesystems used.
TARGET_ARCH : The architecture of the device being built
PREFERRED_PROVIDER_virtual/kernel : The kernel recipe to use
SERIAL_CONSOLE : Speed and device for the serial console to attach. Passed
to the kernel as the console parameter, e.g. 115200 ttyS0
KERNEL_IMAGETYPE : The type of kernel image to build, e.g. zImage
✓ Describe your machine in a README file
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