• Table of contents
• Funding
  • Funding procedure
    • Tasks accepted for funding
    • Applicant criteria
    • Grant application template
      • Contact information
      • General project information
      • Requested support
      • How may we handle your information
    • Discussions
  • Port Replicant to a newer Android version
    • Subtasks
    • Add support for devices with an upstream Linux kernel
    • Add support for more recent smartphones
    • Add support for the devices supported in Replicant 6.0 and 4.2
    • Support in-system upgrades
    • "Finish porting Replicant to a newer Android version" nlnet Grant application
      • Contact information:
      • General project information
      • Requested support
  • Graphics acceleration
    • Subtasks
    • SwiftShader
    • llvmpipe optimizations
    • Lima driver
    • Software Bill of Materials
    • "Graphics acceleration on Replicant" nlnet Grant application
  • Finish to port the Galaxy S III (I9300) and the Galaxy Note 2 (N7100) to Mainline Linux
    • • "Finish to port the Galaxy S III (I9300) and the Galaxy Note 2 (N7100) to Mainline Linux" nlnet Grant application

Funding¶

Funding procedure¶

Tasks accepted for funding¶

• Finish porting Replicant to a newer Android version
• Graphics acceleration

Applicant criteria¶

• The applicants will need to already have Patches in Replicant to apply. So if you want to apply and don't have any patches in Replicant, the easiest way is just to send some useful patches.
• The applicants will need to be able to demonstrate that they have the required skills by showing contributions in free and open source project in similar areas.
• The applicants will need to be able to do contract work

The application criteria wrere handled by the NLnet foundation.

Grant application template¶

url: https://nlnet.nl/propose/
scope : Is it per task?

Contact information¶

General project information¶

Requested support¶

Describe the ecosystem of the project, and how you will engage with relevant actors and promote the outcomes?

The Replicant project contributors and the FSF will supervise
contractors to do the work.

I will write a blog post to announce that the Replicant project
has got some funding for this specific task, and that it is
looking for a contractor to work on it. This is to make sure
that everyone has equal chances in the application process.

Then the most suited contractor will be selected. Only contractors
that already have worked on similar tasks as part of free and open
source software projects will be chosen. This way we can look at
their existing contributions and make sure that they are able to
do the task before engaging with them.

The Replicant project will also make sure that the contractor has
or gets the hardware required to work on the task, before starting
to work on it.

How may we handle your information¶

Discussions¶

There is a thread about funding on the mailing list about that

Port Replicant to a newer Android version¶

• Replicant is currently lagging behind with security fixes
• Replicant cannot be built from a GNU/Linux distribution that follows the Free Software Distribution Guidelines

• A computer that is able to build Replicant.
• A smartphone or tablet that can easily supported by the new version of Replicant and that meet Android 9 HardwareRequirements.

• Remove all proprietary components of LineageOS and make sure that Replicant follows the Free Software Distributions Guidelines"
• Port all the changes needed to successfully boot without any proprietary software in Replicant
• Make sure that most of the security issues are fixed, and lower the attack surface if possible.
• Make sure that Replicant can be built on a GNU/Linux distribution that follows the Free Software Distributions Guidelines
• Rebrand LineageOS as Replicant

Funding: We could apply to https://nlnet.nl/PET

Subtasks¶

• Add support for devices with an upstream Linux kernel
• Add support for more recent smartphones
• Add support for the devices supported in Replicant 6.0 and 4.2
• Support in-system upgrades

Add support for devices with an upstream Linux kernel¶

It would also be useful to support devices using kernels that are based on upstream Linux with the least amount of kernel changes possible:

Currently, Replicant uses a dedicated Hardware Abstraction Layer per device, because device manufacturers implemented non-standard kernel interfaces. However, Android works with mainline kernels and supports plug-n-play hardware nowadays, so it makes sense to have generic Hardware Abstraction Layers for the standard interfaces of the Linux kernel (ALSA, V4L2, etc).

See also the wiki page on Upstream Linux for more details on why using upstream kernel is beneficial, and for what devices to choose to work on this task.

• A device that is already well supported by the Upstream kernel. That device don't need to be already supported by LineageOS or even Android.

Difficulty: Medium

Requirements/Prerequisites: Knowledge of C, some C++, the ability to understand Java, kernel interfaces knowledge

• Basic features working (graphics, touchscreen, buttons, audio, and telephony if there is a modem) for at least one device that use a kernel that is very closely based on upstream Linux with the generic HALs.

Add support for more recent smartphones¶

The most recent smartphones that Replicant support are quite old (they were made around 2013). The goal here is to add support for more recent smartphones in Replicant.

Even if we think that it's at lot more important to support devices that are better for freedom (samsung devices usually have a nonfree bootloaders), adding supporting common (Samsung) phones and tablets is relatively easy and fast to do and could be a good way to get started in contributing to Replicant.

• has an isolated modem (no shared memory between the modem and the processor running Android)
• meets Android 9 HardwareRequirements to still be useful when Replicant will be ported to Android 9
• has a modem that can easily be supported by samsung-ril and libsamsung-ipc
• is or will be supported by lineageOS

Make sure to evaluate the device before starting to work on it. Some devices have been evaluated in the TargetsEvaluation wiki page. There is also a forum section for devices evaluation.

• One or more smartphones that are already well supported by LineageOS or the AOSP project and that can easily be added in Replicant.

Difficulty: Medium

• Basic features working (graphics, touchscreen, buttons, audio, and telephony if there is a modem) without requiring Replicant or the user to install or ship nonfree software or firmwares.

Add support for the devices supported in Replicant 6.0 and 4.2¶

When porting Replicant to a new version, it's also a good idea to keep supporting all the devices we supported in the older versions, however this is not always possible or desirable.

In order not to require too much work, devices that were previously supported will have to meet the HardwareRequirements of the new Android version. Here many of the devices already supported by Replicant 6.0 already meet such requirements.

• The port to the new Android version needs to be complete for at least one device before starting to work on this.
• All the devices will need to be shipped to (or acquired by) the person working on this task before starting to work on this.

• For each device: evaluate if they meet the hardware requirements of the new Android version and document that in the wiki in an appropriate location ( like HardwareRequirements for instance)
• For each device: basic features working (graphics, touchscreen, buttons, audio, and telephony if there is a modem) without requiring Replicant or the user to install or ship nonfree software or firmwares.

Difficulty: Medium

Support in-system upgrades¶

It would be useful for a Replicant device to be able to update itself to a new version of Replicant without requiring being connected to a PC. LineageOS already supports this; we suspect that it should be possible to adapt this LineageOS functionality to Replicant.

Whenever possible, it would be useful to complete and submit some of the code written for Replicant to LineageOS.

Difficulty: Medium

• In-system updates working without being connected to a PC

"Finish porting Replicant to a newer Android version" nlnet Grant application¶

Contact information:¶

General project information¶

Replicant is a fully free software Android distribution which
is approved by the FSF (http://gnu.org/distros).

The combination of Android Open Source Project source code with
the Linux source code provided by the device vendor is not
sufficient to produce a fully free Android distribution that
works: a lot of the code that makes critical hardware components
work (the modem, graphics, audio, GPS, etc) is in userspace.
Because of that, most device manufacturers don't release them as
free software.

To make such hardware work, the Replicant project manages to
replace or avoid such nonfree software.

Replicant is currently based on LineageOS 13.0 which in turn is based
on Android 6.0.1 which are both not supported anymore. Replicant is
based on LineageOS because it supports way more smartphones and
tablets than the Android Open Source Project.

The project consists in porting Replicant changes on top of the
Android 9 release of the Android Open Source project,
and when LineageOS 16 will be ready, to backport our changes on
top of LineageOS 16.

Requested support¶

Explain what the requested budget will be used for?

The budget will only be used to fund this task through contract work.

We think it will take something between 3 and 6 months of work
for one full time developer.

However it is always difficult to evaluate precisely the amount of time
that this kind of project would take as sometimes it can be slowed down
a lot due to bugs needing to be fixed.

For instance, when adding support for the Nexus One to Replicant,
a lot of time was spent dealing with display issues that didn't affect
the upstream projects, because they relied on the GPU which required
nonfree software to work.

If we take the cost of a Freelance developer in the USA (75$ to 150$
per hour) as a basis, to enable people living in Europe and the USA
to apply, we can fund a developer to work on it for a period that
is mostly equivalent to something between 2 to 4 months full
time.

So far we have at least one person interested in working on it
as a contractor (me), and one volunteer who wants to work on it at the
same time, but who cannot do it full time. We will make sure
that everybody has a chance to apply for doing contract work.

If the work is not done when the 50000E run out, and if we cannot
make sure that it will be completed by volunteers in a reasonable
timeframe, the Replicant project will most probably use its existing
funds to pay for contract work to make sure that this task is completed.

The Replicant project will also take care of ensuring that the
people that will work on this task have the necessary hardware to
do it, for instance by shipping or reimbursing the purchase of a
compatible smartphone with the Replicant project money.

Once we have the Samsung Galaxy SIII fully working with
Replicant 9, we will add support for most smartphones
and tablets we currently support in Replicant, and add support
for more recent smartphones (the most recent one we currently
support has been released in 2013).

We also have a very basic documentation on the Android 9 port here:
https://redmine.replicant.us/projects/replicant/wiki/Porting_Replicant_to_Android_9

Compare your own project with existing or historical efforts.

Upgrading Replicant to a new Android version usually took about 2 or 3
months of full-time equivalent work for one person.
Here, we already have a device (The Galaxy SIII 4G) booting under Android 9
master before the release, with a kernel that is closely based on upstream
Linux, but a lot still needs to be done (modem, audio, sensors, etc) and
validated. The Android architecture also changed a lot more between Android
6.0.1 and Android 9 than it did when we ported Replicant to newer Android
versions.

What are significant technical challenges you expect to solve during the project, if any?

We will also need to make sure that Replicant 9 can be built with a
GNU/Linux distribution that is approved by the FSF. This could be
challenging if they lack some of the packages required to build Android.

Describe the ecosystem of the project, and how you will engage with relevant actors and promote the outcomes?

This project will re-use code from several projects such as Android,
drm-hwcomposer, Mesa and Lima driver. Whenever possible we will foster
collaboration with these projects and submit our changes upstream.

The Replicant project contributors and the FSF will supervise
contractors to do the work.

A blog post will announce that the Replicant project
has got some funding for this specific task, and that it is
looking for a contractor to work on it. This is to make sure
that everyone has equal chances in the application process.

Then the most suited contractor will be selected. Only contractors
that already have worked on similar tasks as part of free and open
source software projects will be chosen. This way we can look at
their existing contributions and make sure that they are able to
do the task before engaging with them.

The Replicant project will also make sure that the contractor has
or gets the hardware required to work on the task, before starting
to work on it.

Graphics acceleration¶

• Critical applications like web browsers crash due to lack of GLES 2.0 (#705). Replicant currently uses an out-dated browser that has many security flaws.
• Replicant relies on patches to the Android framework to make things like the camera application work.
• The rendering speed has degraded over the newer Android versions, like Android 6. Even applications that do not crash become difficult to use due to the huge rendering delays.

This task aims to fix all these severe issues by putting together a new graphics stack for the Android 9 port. This new graphics stack must be compatible with Android 9 Hardware Abstraction Layers (HAL) and provide at least GLES 2.0 rendering. It should be flexible enough to do software rendering with Mesa or SwiftShader (Google's current software renderer), and also GPU rendering on devices where a free GPU driver is available.

Joonas Kylmälä has done some introductory work on the Android 9 port for the i9305, and found a way to have it rendering to the screen. He put together a graphics stack composed of: gbm_gralloc (Gralloc HAL) + drm_hwcomposer (Hardware Composer HAL) + Mesa with kms_swrast driver with softpipe backend (CPU software renderer for GLES). This will be the starting point for this task.

Joonas' prototype shows that Replicant can use gbm_gralloc, an existing graphics memory allocator (gralloc) HAL maintained(ish) by Android-x86, in conjunction with drm-hwcomposer, a libre implementation of Android's Hardware Composer HAL based on Linux's DRM, to achieve software rendering with Mesa. This solution avoids the need to write a custom gralloc for Replicant, and takes advantage of the hardware acceleration for composition provided by drm-hwcomposer on devices with a free software DRM driver (e.g. exynos-based smartphones and tablets).

Much more testing is needed to confirm that gbm_gralloc can be the definitive gralloc HAL on Replicant 9. It still wasn't tried with SwiftShader, or even Mesa's llvmpipe backend, which is a must since the softpipe backend is too slow to be usable.
Joonas' tests showed that some other components will need our attention, mostly the drm/exynos driver. In order to make drm/exynos work with gbm_gralloc and drm-hwcomposer Joonas had to disable DRM-Auth and hack some missing pixel formats into it by using the default pixel format for everything. Besides drm/exynos, we will also have to make the graphics stack work with the virtual GEM (vGEM) driver, in order to support devices that lack a real drm driver.

The major and first goal of this task is thus to build upon Joonas's prototype and put together a stable and fully free graphics stack, compatible with GLES 2.0, that does software rendering through Mesa's llvmpipe with a decent performance.

Hardware requirements: A computer that is able to build Replicant. A Samsung Galaxy S3 or S3 4G to run the current Replicant 9 port.

Difficulty: Medium / Hard

Requirements/Prerequisites: Knowledge of C++, kernel interfaces knowledge or the ability to learn them

• Graphics stack with decent performance on software rendering
• Working GLES 2.0 implementation
• Fast enough graphics
• F-Droid applications not crashing anymore because of GLES.

Time estimation:

Subtasks¶

• SwiftShader
• llvmpipe optimizations
• Lima driver

SwiftShader¶

SwiftShader is Google's current software renderer that is capable of GLES 2.0 and is now under work to support Vulkan.

Mesa is the preferred renderer on Replicant for several reasons such as its support for both software and hardware (GPU) rendering, and its big community, with hundreds of active contributors. However, Mesa lacks a Vulkan software renderer. With Vulkan soon becoming a requirement for new Android versions, we must make sure that Replicant's graphics stack can use SwiftShader in order to become futureproof. Furthermore, SwiftShader was built with performance in mind, specially for ARM CPUs, and may bring speed improvements on some devices.

The goal of this sub-task is thus to create a compile-time or run-time option that allows using Replicant 9 with SwiftShader as it's software renderer instead of Mesa.

Hardware requirements: A computer that is able to build Replicant. A smartphone or tablet that is supported by Replicant to be able to test the result.

Difficulty: Medium

Requirements/Prerequisites: Knowledge of C++, Makefiles and git. Android's graphics stack knowledge or the ability to learn them.

• SwiftShader running on Replicant.
• Working Vulkan implementation.

Time estimation: 40 man-hours.

llvmpipe optimizations¶

Mesa is a highly versatile library that can be extended with device drivers to allow it to be used in different environments ranging from software emulation to complete hardware acceleration. One such driver is the Gallium llvmpipe driver, which is a software rasterizer that uses LLVM to do runtime code generation. It only needs a CPU to run graphics computations and thus brings full GLES support to all Replicant devices.

llvmpipe has been integrated in Replicant 6 but it's not activated by default yet as it is very slow. It is also not fully complete.

To fix that, llvmpipe and/or the integration of it in Replicant should be optimized. We should first start by configuring llvmpipe and/or Mesa to not implement very expensive OpenGL operations. If that's not sufficient, or if that breaks application compatibility, various software or hardware features (ARM NEON, hardware 2D acceleration, etc) could be used to improve the speed.

Considerable speed improvements may be achieved with a fine-tuned emulation for division instructions. The ARM cores on many Replicant devices do not have hardware support for the SDIV/UDIV instructions. We should profile some apps and check whether GLES functions requiring divisions are to blame for the poor performance.

Hardware requirements : A computer that is able to build Replicant. A smartphone or tablet that is supported by Replicant to be able to test the result.

Difficulty: Medium / Hard (depending on the amount of optimizations required)

Requirements/Prerequisites: See with Mesa project

Expected outcomes: faster llvmpipe on ARM devices, able to run apps such as Fennec F-Droid (Firefox).

Time estimation:

Lima driver¶

Lima is a free software Mesa driver for ARM Mali-4xx (Utgard) GPUs. These GPUs are present in several Replicant supported devices such as Galaxy S2, S3, S3 4G, Note and Note 2.

Lima aims to full GLES support but it is still in development. However the current implementation status already allows the hardware acceleration of several tasks. GPU-based hardware acceleration is faster and less power hungry than software rendering, both by several orders of magnitude. It would allow Replicant devices to run applications with a performance close to that of non-free devices.

Hardware requirements : A computer that is able to build Replicant. A Replicant device with a Mali-4xx GPU that can run mainline Linux (e.g. Galaxy S3 or Note 2).

Difficulty: Medium

Requirements/Prerequisites: See with Lima project

Expected outcomes: Lima driver being used for GLES rendering on a supported device.

Software Bill of Materials¶

• Replicant 9
• Mesa (in particular: Gallium llvmpipe driver)
• gbm_gralloc
• drm-hwcomposer
• Linux kernel (in particular: drm/exynos driver and vGEM driver)
• SwiftShader
• Ne10 library
• Neon Intrinsics
• Lima

"Graphics acceleration on Replicant" nlnet Grant application¶

Abstract: Can you explain the whole project and its expected outcome(s) in 1200 characters

Replicant is a fully free software Android distribution which is approved by the
FSF. All supported devices on Replicant currently lack a free software driver
for their GPU. As such, OpenGL ES (GLES) rendering must be done on the CPU
through software rendering (SR).

Replicant's current renderer is both incomplete and slow. It causes essential
apps like web browsers to crash due to lack of GLES 2.0, and many other
apps run too slow to be usable.

This project aims to fix this by complementing Android's 9 graphics stack.
Adding a few missing components will created of a fully-free, fast and compliant
graphics stack.

First we will write a gralloc (graphics memory allocator) tailored for SR that
is compatible with drm-hwcomposer (a libre implementation of Android's Hardware
Composer HAL). This gralloc enables drm-hwcomposer to work with SurfaceFlinger
and SwiftShader, creating a stack capable of GLES 2.0 on the CPU of all Replicant
devices.

Afterwards we will integrate and optimize Mesa's llvmpipe SR, which offers better
community support than SwiftShader. As last step we will add support for the
Lima driver, which will bring an even faster GPU-backed GLES to at least 5
devices.

Explain what the requested budget will be used for?

The budget will only be used to fund this project through contract work.

We estimate that this project should take 868 man-hours to reach full completion,
with 632 man-hours being enough to reach all software rendering goals, leaving only
the GPU rendering to be done. A detailed run-down of this estimate is available at
https://redmine.replicant.us/projects/replicant/wiki/Tasks_funding#Graphics-acceleration

So far we have a team of two people interested on working on this project (the
two authors and submitters of this application). Both can commit to the project
on a part-time regime (17.5 hours per week), which means that the project should
be fully completed in about 6 months.

We will make sure that everybody has a chance to apply for doing contract work.
If we take the cost of a freelance developer in the USA (75 to 150 USD
per hour) as a basis, to enable people living in Europe and the USA
to apply, we can fund between 380 and 760 man-hours with the 50000 EUR budget.
This should be enough to cover all work on software rendering plus the initial
work on GPU rendering.

As happens on all software projects, getting a precise time/effort evaluation is
a difficult endeavour, specially when dealing with a project that is heavy on
research such as this one.

If the software rendering goals are not reached when the 50000 EUR budget runs
out, or if the Replicant project deems it necessary to have GPU rendering, it
will use its existing funds to pay for contract work if no volunteers are found
to finish the project.

The Replicant project will also make sure that the people working on this project
have the necessary hardware to do it, for instance by shipping or reimbursing the
purchase of a compatible smartphone with the Replicant project funds.

Compare your own project with existing or historical efforts.

Past Replicant versions have relied on patches to the Android framework to make
software rendering work. These patches were quite specific for Replicant and
had no use elsewhere. This made them unfit for upstreaming or sharing with any
other project.

Android's Project Treble new graphics stack allows us to follow a different
approach this time. Instead of patching the Android framework, we will
implement one of the well defined Android HALs (Hardware Abstraction Layer):
the gralloc HAL. The end result will be a software library that can prove to be
useful on several projects besides Replicant (e.g. Android-x86 project) and
thus fit for upstreaming.

Furthermore, past Replicant versions relied on Google's software renderers
(ligAGL and libpixelflinger) for OpenGL ES support. As quite a few other
Google's open-source projects, these two had no community behind them and got
stalled as soon as Google deprecated them.

This time will we take a different approach. Although our first graphics stack
will rely on Google's SwiftShader renderer, we will then move our efforts into
Mesa. Mesa is a big community project, with hundreds of active contributors and
great community support. It includes the llvmpipe software renderer along with
new drivers in development for GPUs present on current and future Replicant
devices. Mesa should provide a stable and maintained platform for years to come.

What are significant technical challenges you expect to solve during the project, if any?

We expect to solve significant technical challenges during this project:
1. Implementation of the first Android gralloc library compatible with software
rendering.
2. Development of free-software benchmarks for OpenGL ES on Android, used to test
our optimizations to llvmpipe.
3. Optimization of llvmpipe by at least one order of magnitude.
4. Running an exynos based smartphone with fully free-software GPU graphics
acceleration.

Describe the ecosystem of the project, and how you will engage with relevant actors and promote the outcomes?

This project will re-use code from several projects such as Android,
drm-hwcomposer, Mesa and Lima driver. Whenever possible we will foster
collaboration with these projects and submit our changes upstream.

The Replicant project contributors and the FSF will supervise
contractors to do the work.

A blog post will announce that the Replicant project
has got some funding for this specific task, and that it is
looking for a contractor to work on it. This is to make sure
that everyone has equal chances in the application process.

Then the most suited contractor will be selected. Only contractors
that already have worked on similar tasks as part of free and open
source software projects will be chosen. This way we can look at
their existing contributions and make sure that they are able to
do the task before engaging with them.

The Replicant project will also make sure that the contractor has
or gets the hardware required to work on the task, before starting
to work on it.

Finish to port the Galaxy S III (I9300) and the Galaxy Note 2 (N7100) to Mainline Linux¶

The the Galaxy S 2 (I9100), Galaxy S 3 (I9300) and Galaxy Note 2 (N7100) currently use a kernel based on a vendor fork of Linux, which poses a maintainability and security issue. Forkbomb has done some initial work on porting these devices to use mainline Linux. You can help by continuing this work. This would also enable these devices to use generic hardware abstraction layers (HAL) when abstractions layers are ready, and to do some research on whether the TrustZone operating system can be removed from such devices.

Hardware requirements : A computer that is able to build Replicant. A Galaxy S 2 (I9100), Galaxy S 3 (I9300) or Galaxy Note 2 (N7100), and a serial port adapter to get the kernel boot logs.

Difficulty: Medium

Requirements/Prerequisites: C programming language, driver development

Expected outcomes: Audio working, modem working, and Replicant or LineageOS booting with mainline Linux.

"Finish to port the Galaxy S III (I9300) and the Galaxy Note 2 (N7100) to Mainline Linux" nlnet Grant application¶

Abstract: Can you explain the whole project and its expected outcome(s).in 1200 characters

Replicant is a fully free Android distribution that is
approved by the FSF (http://gnu.org/distros).

TODO

Explain what the requested budget will be used for?

The budget will only be used to fund this task through contract work.

We think it will take something between 3 and 4 month of work
for one full time developer.

If we take the cost of a Freelance developer in the USA (75$ to 150$
per hour) as a basis, to enable people living in Europe and the USA
to apply, we can fund a developer to work on it for a period that
is mostly equivalent to something between 2 to 4 months full
time.

The Replicant project will take care of making sure that the
people that will work on this task have the necessary hardware to
do it, for instance by shipping or reimbursing the purchase of a
compatible smartphone with the Replicant project money.

Compare your own project with existing or historical efforts.

TODO

What are significant technical challenges you expect to solve during the project, if any?

TODO