Replicant

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h1. TestingInfrastructure

h2. Applications that can be used to do some testing on the device

* https://f-droid.org/wiki/page/org.zeroxlab.zeroxbenchmark

h2. Projects and/or hardware that can be used to do functional testing

h3. Lava

"Lava":https://www.linaro.org/engineering/projects/lava/ can be used to do functional tests on real hardware. It can be easily installed on PureOS, an FSDG compliant GNU/Linux distribution.

h3. Labgrid

"Labgrid":https://labgrid.readthedocs.io/en/latest/ has features similar to Lava but it is probably easier to learn because it's probably way easier to get started with it.

h3. OsmoGSMTester

The "OsmoGSMTester project":https://osmocom.org/projects/osmo-gsm-tester is able to be interfaced with the Android RIL through ofono and can emulate a GSM network with the help of a compatible GSM base station or SDR.

This "presentation from 2019":https://media.ccc.de/v/osmodevcon2019-119-osmo-gsm-tester-e-gprs-test-setup has many insights on what kind of issue we might expect in interfacing it with smartphones.

h3. Simtrace2

The "Simtrace 2 project":https://osmocom.org/projects/simtrace2/wiki can be used, along with SIM card readers to programmatically feed a SIM card to a smartphone. This can be used to run test on real networks.

h2. Replicant supported devices and testing

h3. Requirements

* Antenna connector for the modem

* The ability to control the device buttons in order to be able to programmatically power on and off the device, and trigger boots into the bootloader and recovery

* Optionally a way to connect to the serial port, programmatically

h3. Galaxy SII (GT-I9100)

* The Galaxy SII (GT-I9100) has:

** An antenna connector. According to the "External Antenna Socket - WARNING forum thread on XDA":https://forum.xda-developers.com/t/external-antenna-socket-warning.1273292/page-6 , it's an MS-162

** The SOC serial port that is accessible behind the USB connector at a low voltage

** A full size mini-sim (easier to interface with)

Holding the smartphone in place:

* The smartphone could either be screwed on a metallic surface or an external case could be screwed on a metallic surface enabling the smartphone not to move.

SIM cards:

* Simtrace and Simtrace 2 both "lacks screw holes":https://osmocom.org/issues/3711 so a way must be found to make sure that it doesn't move as it uses flex cables to interface with the SIM socket of the smartphone. That may be fixed in a subsequent hardware revision.

Serial port and USB:

Buttons:

Battery:

Antenna connector and GSM tower or SDR:

The Galaxy SII (GT-I9100) has two antenna connectors:

* One internal connector, TODO: find the connector type

* One external connector, TODO: Find the connector type

h4. Example setup

See also the links inside the [[Serial_port]] article for more background on how to get serial port access on devices like the Galaxy SIII (GT-I9300) or the Galaxy SII (GT-I9100).

!i9100.jpg!

See https://git.replicant.us/contrib/GNUtoo/test-infrastructure.git for the source of the file.

h4. Using a device without a battery.

* "How to use a Galaxy SIII without a battery":https://techblog.jeppson.org/2017/12/revive-old-samsung-galaxy-s3/ : It doesn't look very safe to do that as the phone is probably not expecting 5V on the battery connector but it gives some idea of the peak tolerances.

* The Galaxy SIII 4G (GT-I9305) could probably work at lower voltages like 3.3V through the battery connector, but it would require testing it. In that case it might also be a good idea to test it in all configurations (all hardware features being used, cpuburn etc).

* The 4 pin 'FPC' style battery connector available from amazon, marketed as being for the 'S4 value edition i9515' (https://amazon.de/gp/product/B0813JBW8S) is capable of contacting the Galaxy SIII (GT-I9300)'s battery.

h4. Sumarry 

| Device                  | Modem antenna connector | Compatible software       | Comments                                                                                                  |                         

| Motorolla C155          | MS-147                  | * OsmocomBB

                                                      * Old Nuttx revisions     | Could be used as reference phone as it's probably already supported by the Osmocom testing infrastructure |

| Galaxy SII (GT-I9100)   | MS-162                  | * Replicant 4.0, 4.2, 6.0

                                                     * Upstream Linux (partial) |

| Galaxy Nexus (GT-I9250) | ?                       | * Replicant 4.0, 4.2, 6.0 | We can get some GSM traces in wireshark with xgoldmon                                                     |

| Galaxy SIII (GT-I9300)  | ?                       | * Replicant 4.0, 4.2, 6.0

                                                     * Upstream Linux (partial) |

h2. USB modems

When [[XMMProtocolInterfaces|trying to enable protocol tracing in modems]] we can connect the device modem (somewhat directly) to a laptop

Questions:

* Do we have samsung-ipc on top of the virtual UARTs?

* The cbd daemon mentioned "in the blog post about booting the Galaxy S7 modem":https://eighty-twenty.org/2020/09/10/booting-samsung-galaxy-s7-modem  doesn't list UART as main link though.

* Adding the modem USB id when in debug mode (1519:0020) in a search engine shows various usb keys

* Do phones like the Galaxy SII have smasung-ipc on top of the USB link or UART links when in debug mode?

h2. Pure software setup

h3. lightweight test infrastructure for libsamsung-ipc

It might be possible to have a pure software test infrastructure with libsamsung-ipc.

It could be done more or less like that:

test script <-> ipc-modem or other programs <-> libsamsung-ipc <-> Linux kernel <-> VHCI <-> software sending USB packets

We have several choices for the Linux kernel:

| Kernels                   | Comments |

| User mode Linux (ARCH=um) | (+) Very lightweight, runs completely in userspace 

                              (-) Requires patches for USB / VHCI                               |

| Linux + libvirt + kvm     | (-) Require some virtualization setup that requires dedicated RAM 

                              (+) Probably works unpatched                                      |

And there is already some projects emulating usb devices:

| Project     | Description               |   comments                         |

| gnuk        | USB token software        | can build for gnulinux             |

| choptix     | Library used by gnuk      | More simple examples               |

| simtrace2 ? | SIM tracing and MITM tool | Probably uses vusb for testing too |

So it might be possible to modify them to send some simple USB packets captured with wireshark / tshark / tcpdump.

h4. user mode Linux

I've already managed to find a configuration that works in an FSDG compliant way:

| Settings                                                                     | Status           |

| *kernel*: kernel_replicant_linux 

           (replicant-11-test branch at the time of writing) 

  *compilation settings*: ARCH=um

  *Host architecture*: x86_64

  *kernel defconfig*: x86_64_defconfig

  *Target Distribution*: Parabola x86_64

  *commandline arguments*: ./linux mem=2047M ubd0=parabola.img root=/dev/ubda1 | Boots fine       |

| *kernel*: kernel_replicant_linux or upstream Linux 

  *compilation settings*: ARCH=um

  *Host architecture*: i686 or x86_64

  *kernel defconfig*: i686_defconfig                                           | Fails to compile |

TODO:

* We probably need to make i686 and armv7 to work too.

* We need to find and port the USB patches on top of kernel_replicant_linux

* We also need to setup USB somehow with vhci_hcd and so on

* We still need to find a very simple stack to send URBs.