docs/chamelium.txt - platform/external/igt-gpu-tools - Gitiles

 Chamelium Support in IGT
 ========================

 This document provides information, instructions and a tasks list for Chamelium
 support in IGT.

 Introduction
 ------------

 The Chamelium is a platform that acts as a display monitor emulator. It provides
 advanced access and control over the various signals a display receives.

 As such, it allows testing display features that can otherwise not be tested in
 IGT without external hardware.

 The platform was developed by Google in order to test display and audio-related
 features of ChromeOS devices. It was initially developed internally by Google as
 part of the ChromeOS effort under the name Chameleon and was later made external
 as part of the ChromiumOS effort, under the name Chamelium.

 It consists of a custom-made display emulator board connected to an Arrow SoCKit
 via a flexible cable, with two DisplayPort connectors, one HDMI and one VGA.

 The SoCKit uses a Cyclone V SoC, with both a FPGA and an ARM CPU. While the FPGA
 is used for logic control, the CPU runs daemons that allow the board to be
 controlled over the network via a XMLRPC interface.

 Documentation
 -------------

 Documentation about the Chamelium is made available by Google through the
 ChromiumOS projet wiki: https://www.chromium.org/chromium-os/testing/chamelium

 Deploying the Chamelium With IGT
 --------------------------------

 Instructions from the ChromiumOS wiki detail how to setup the Chamelium:
 https://www.chromium.org/chromium-os/testing/chamelium#TOC-Setting-up-Chamelium

 The should be followed up until the "Setup your Linux host, DUT and the FPGA"
 section. At this point, IGT has to be configured to connect to the Chamelium.

 It may be necessary to give the Chamelium a static IP address, depending on
 the network setup. This can be configured (via the serial console) by editing
 the Debian-styled /etc/network/interfaces configuration file.

 Chamelium support requires setting up dedicated IGT configuration, as explained
 in the Core and Chamelium parts of the IGT API Reference in the documentation.

 Note that running the chamelium tests with the Chamelium configuration deployed
 and the Chamelium disconnected or unreachable will result in network timeouts
 that take seconds. It is thus preferable (especially in the case of an automated
 CI system with a shared testlist) to remove the Chamelium configuration from the
 hosts that shouldn't connect to the Chamelium so that they can be skipped, which
 is faster than a network timeout.

 It should also be noted that each Chamelium platform should only be used for
 testing a single target device at a time. This is because the reset call issued
 by the IGT tests is common to all connectors and thus one machine running a test
 on a given connector may reset the Chamelium while another machine is running
 a test on another connector.

 An example fully-featured configuration follows:
 [Common]
 FrameDumpPath=/root/

 [Chamelium]
 URL=http://192.168.72.1:9992

 [Chamelium:DP-1]
 ChameliumPortID=1

 [Chamelium:HDMI-A-2]
 ChameliumPortID=3

 [Chamelium:VGA-1]
 ChameliumPortID=4

 [DUT]
 SuspendResumeDelay=2

 Debugging the Chamelium
 -----------------------

 Logs that may be useful for debugging can be obtained either by connecting to
 the board via SSH or serial console and looking at the daemon logs from
 /var/log, such as:
 $ tail -f /var/log/chameleon*

 Daemon Source, Build and Deploy
 -------------------------------

 Source code for the daemon running on the Chamelium is available at:
 https://chromium.googlesource.com/chromiumos/platform/chameleon/

 Building the daemon requires a GNU EABI ARMv7 GCC toolchain, that must be
 specified via the CC variable, such as:
 $ make CC=arm-linux-gnueabihf-gcc

 The result can be deployed to the chamelium with the remote-install target and
 specifying the network address for the chamelium via the CHAMELEON_HOST
 variable, such as:
 $ make remote-install CHAMELEON_HOST=192.168.72.1

 The process requires the Chamelium to be connected to the Internet to succeed.

 Contributing Changes to the Daemon
 ----------------------------------

 Contributions to the Chamelium daemon, just like any contribution to ChromiumOS,
 are submitted and reviewed at: https://chromium-review.googlesource.com/

 The ChromiumOS project provides an extensive developer guide:
 https://www.chromium.org/chromium-os/developer-guide that assumes running within
 the ChromiumOS build system. Since this is likely not the case for contributing
 to the Chamelium daemon, only the part about uploading changes is relevant:
 https://www.chromium.org/chromium-os/developer-guide#TOC-Upload-your-changes-and-get-a-code-review

 Most of the process is about using the Gerrit web interface for submitting and
 having the change reviewed and not forgetting the Change-Id, TEST= and BUG=
 fields in the commit.

 Current Support in IGT
 ----------------------

 Support for the Chamelium platform in IGT is found in the following places:
 * lib/igt_chamelium.c: library with Chamelium-related helpers
 * tests/chamelium.c: sub-tests using the Chamelium

 As of late August 2017, the following features are tested by IGT:
 * Pixel-by-pixel frame integrity tests for DP and HDMI
 * Error-trend-based frame integrity tests for VGA
 * CRC-based frame integrity tests for DP and HDMI
 * Hotplug event simple tests for all interfaces
 * Hotplug event stressing tests, emulating a flaky cable for DisplayPort and
   HDMI
 * Hotplug event during suspend test for all interfaces, either separately for
   each interface or combined
 * EDID display identifier integrity check for all interfaces
 * EDID display identifier change during suspend for all interfaces

 Future Developments
 -------------------

 With the current generation of the hardware platform, support for testing a
 number of additional display features could be included as future developments,
 including:
 * Audio capture from HDMI and DP
 * High-bandwidth Digital Content Protection (HDCP) streaming to the display
 * Remote control forwarding (CEC) sent from the display
 * YUV colorspace for HDMI, instead of RGB
 * Partial testing of DP Multi-Stream Transport (MST) using an external MST hub
   and the two available DP connectors of the platform

 While HDCP is already supported by the Chamelium daemon, features such as CEC
 and YUV are not and must be implemented there before any support for them can
 be added to IGT. Audio is supported by the Chamelium daemon for HDMI only and
 a way to retrieve the captured data via the XMLRPC interface needs to be added
 to the daemon.
	Chamelium Support in IGT
	========================

	This document provides information, instructions and a tasks list for Chamelium
	support in IGT.

	Introduction
	------------

	The Chamelium is a platform that acts as a display monitor emulator. It provides
	advanced access and control over the various signals a display receives.

	As such, it allows testing display features that can otherwise not be tested in
	IGT without external hardware.

	The platform was developed by Google in order to test display and audio-related
	features of ChromeOS devices. It was initially developed internally by Google as
	part of the ChromeOS effort under the name Chameleon and was later made external
	as part of the ChromiumOS effort, under the name Chamelium.

	It consists of a custom-made display emulator board connected to an Arrow SoCKit
	via a flexible cable, with two DisplayPort connectors, one HDMI and one VGA.

	The SoCKit uses a Cyclone V SoC, with both a FPGA and an ARM CPU. While the FPGA
	is used for logic control, the CPU runs daemons that allow the board to be
	controlled over the network via a XMLRPC interface.

	Documentation
	-------------

	Documentation about the Chamelium is made available by Google through the
	ChromiumOS projet wiki: https://www.chromium.org/chromium-os/testing/chamelium

	Deploying the Chamelium With IGT
	--------------------------------

	Instructions from the ChromiumOS wiki detail how to setup the Chamelium:
	https://www.chromium.org/chromium-os/testing/chamelium#TOC-Setting-up-Chamelium

	The should be followed up until the "Setup your Linux host, DUT and the FPGA"
	section. At this point, IGT has to be configured to connect to the Chamelium.

	It may be necessary to give the Chamelium a static IP address, depending on
	the network setup. This can be configured (via the serial console) by editing
	the Debian-styled /etc/network/interfaces configuration file.

	Chamelium support requires setting up dedicated IGT configuration, as explained
	in the Core and Chamelium parts of the IGT API Reference in the documentation.

	Note that running the chamelium tests with the Chamelium configuration deployed
	and the Chamelium disconnected or unreachable will result in network timeouts
	that take seconds. It is thus preferable (especially in the case of an automated
	CI system with a shared testlist) to remove the Chamelium configuration from the
	hosts that shouldn't connect to the Chamelium so that they can be skipped, which
	is faster than a network timeout.

	It should also be noted that each Chamelium platform should only be used for
	testing a single target device at a time. This is because the reset call issued
	by the IGT tests is common to all connectors and thus one machine running a test
	on a given connector may reset the Chamelium while another machine is running
	a test on another connector.

	An example fully-featured configuration follows:
	[Common]
	FrameDumpPath=/root/

	[Chamelium]
	URL=http://192.168.72.1:9992

	[Chamelium:DP-1]
	ChameliumPortID=1

	[Chamelium:HDMI-A-2]
	ChameliumPortID=3

	[Chamelium:VGA-1]
	ChameliumPortID=4

	[DUT]
	SuspendResumeDelay=2

	Debugging the Chamelium
	-----------------------

	Logs that may be useful for debugging can be obtained either by connecting to
	the board via SSH or serial console and looking at the daemon logs from
	/var/log, such as:
	$ tail -f /var/log/chameleon*

	Daemon Source, Build and Deploy
	-------------------------------

	Source code for the daemon running on the Chamelium is available at:
	https://chromium.googlesource.com/chromiumos/platform/chameleon/

	Building the daemon requires a GNU EABI ARMv7 GCC toolchain, that must be
	specified via the CC variable, such as:
	$ make CC=arm-linux-gnueabihf-gcc

	The result can be deployed to the chamelium with the remote-install target and
	specifying the network address for the chamelium via the CHAMELEON_HOST
	variable, such as:
	$ make remote-install CHAMELEON_HOST=192.168.72.1

	The process requires the Chamelium to be connected to the Internet to succeed.

	Contributing Changes to the Daemon
	----------------------------------

	Contributions to the Chamelium daemon, just like any contribution to ChromiumOS,
	are submitted and reviewed at: https://chromium-review.googlesource.com/

	The ChromiumOS project provides an extensive developer guide:
	https://www.chromium.org/chromium-os/developer-guide that assumes running within
	the ChromiumOS build system. Since this is likely not the case for contributing
	to the Chamelium daemon, only the part about uploading changes is relevant:
	https://www.chromium.org/chromium-os/developer-guide#TOC-Upload-your-changes-and-get-a-code-review

	Most of the process is about using the Gerrit web interface for submitting and
	having the change reviewed and not forgetting the Change-Id, TEST= and BUG=
	fields in the commit.

	Current Support in IGT
	----------------------

	Support for the Chamelium platform in IGT is found in the following places:
	* lib/igt_chamelium.c: library with Chamelium-related helpers
	* tests/chamelium.c: sub-tests using the Chamelium

	As of late August 2017, the following features are tested by IGT:
	* Pixel-by-pixel frame integrity tests for DP and HDMI
	* Error-trend-based frame integrity tests for VGA
	* CRC-based frame integrity tests for DP and HDMI
	* Hotplug event simple tests for all interfaces
	* Hotplug event stressing tests, emulating a flaky cable for DisplayPort and
	HDMI
	* Hotplug event during suspend test for all interfaces, either separately for
	each interface or combined
	* EDID display identifier integrity check for all interfaces
	* EDID display identifier change during suspend for all interfaces

	Future Developments
	-------------------

	With the current generation of the hardware platform, support for testing a
	number of additional display features could be included as future developments,
	including:
	* Audio capture from HDMI and DP
	* High-bandwidth Digital Content Protection (HDCP) streaming to the display
	* Remote control forwarding (CEC) sent from the display
	* YUV colorspace for HDMI, instead of RGB
	* Partial testing of DP Multi-Stream Transport (MST) using an external MST hub
	and the two available DP connectors of the platform

	While HDCP is already supported by the Chamelium daemon, features such as CEC
	and YUV are not and must be implemented there before any support for them can
	be added to IGT. Audio is supported by the Chamelium daemon for HDMI only and
	a way to retrieve the captured data via the XMLRPC interface needs to be added
	to the daemon.