Posted by Iliyan Malchev (Venture Treble Architect), Amith Dsouza (Technical Account Supervisor) , and Veerendra Bhora (Strategic Partnerships Supervisor)
Extending Android updates on Qualcomm’s Cell Platforms
Prior to now few years, the newest Android OS has been adopted earlier by OEMs and deployed in bigger numbers to our customers. The expansion in adoption has been pushed by OEMs delivering quicker OS updates, benefiting from the structure launched by Venture Treble.
On the time Android 11 launched there have been 667M lively customers on Android 10, 82% of whom bought their Android 10 construct by way of an over the air (OTA) replace. Regardless of the occasions all through 2020, there’s a continued momentum amongst our companions to both launch their gadgets on Android 11 or supply Android 11 OTAs on their gadgets earlier.
Our efforts until now have been focussed on making OS updates simpler and quicker to deploy. The opposite facet of this coin is supporting updates for an extended time period, and right this moment we’d like to supply an summary of the adjustments we’re making to assist our companions obtain this.
Project Treble was an bold re-architecture of Android that created a break up between the OS framework and device-specific low-level software program (referred to as the seller implementation) via a well-defined, steady vendor interface. As part of this break up, the Android OS framework ensures backward compatibility with the seller implementation, which is checked via a standardized compliance take a look at suite – VTS. With every Android launch, Venture Treble publishes Generic System Images (GSIs) which can be constructed from AOSP sources, and are assured to be backwards-compatible with the earlier 3 variations of vendor implementations, as well as in fact to the present launch—for a complete span of 4 years. Gadgets launching with the brand new Android launch will need to have vendor implementations suitable with that GSI. That is the first car for decreasing fragmentation inside the OS framework. Whereas we enable and encourage our companions to switch the framework itself, the modifications post-Treble have to be executed in a approach that reduces improve prices from one model to the following.
Apart from the reuse of a vendor implementation throughout OS updates, the Treble structure additionally facilitates the re-use of the identical OS framework code throughout completely different vendor implementations.
One other vital change launched by Venture Treble is that new vendor-impacting necessities for Android gadgets are by no means retroactive. They apply solely to gadgets launching on that Android model and to not gadgets upgrading from an older model. The time period vendor-impacting right here refers to necessities for brand spanking new HALs, or for the transport of a more moderen Linux kernel, to the gadget’s vendor implementation. A very good instance is likely to be a brand new revision of the digital camera HAL to help a number of rear digital camera sensors. For the reason that Android framework ensures compatibility with the older HALs, we allow older vendor implementations to be reused by OEMs for upgrades with out the appreciable value of updating them with new necessities.
This precept, mixed with the backwards-compatibility assure, provides gadget producers (OEMs) the flexibleness to help upgrades each quicker (since they must improve simply the framework, which might cowl all of their gadgets, together with these with older variations of the seller implementation), in addition to at a decrease value (since they don’t have to the touch the older vendor implementations).
Nevertheless, seen from a System-on-Chip producers’ perspective, this design introduces extra complexity. For every SoC mannequin, the SoC producers now wanted to create a number of mixtures of vendor implementations to help OEMs who would use that chipset to launch new gadgets and deploy OS upgrades on beforehand launched gadgets.
The result’s that three years past the launch of a chipset, the SoC vendor must help as much as 6 mixtures of OS framework software program and vendor implementations. The engineering prices related to this help restricted the period for which SoC distributors provided Android OS software program help on a chipset. For each single chipset, the software program help timeline would appear like this:
Contemplating that SoC suppliers have dozens of SoC fashions at any level of time, the total image appears nearer to this:
The crux of the issue was that, whereas gadget necessities had been by no means retroactive, the necessities for SoCs had been. For instance on Android Pie, SoCs needed to help two variations of the Digicam HAL API on a chipset if it was used to help new gadget launches and upgrades.
From this attitude, the answer was easy: we needed to prolong the no-retroactivity precept to the SoCs in addition to to gadgets. With this modification, the SoC supplier would be capable to help Android with the identical vendor implementations on their SoCs for gadget launches in addition to upgrades.
In the course of the previous yr, we’ve got been working exhausting to implement this answer. Constructing on our deep collaboration with our colleagues at Qualcomm, right this moment we’re saying the outcomes of this work. Going ahead, all new Qualcomm cellular platforms that make the most of the no-retroactivity precept for SoCs will help 4 Android OS variations and 4 years of safety updates. All Qualcomm prospects will be capable to make the most of this stability to additional decrease each the prices of upgrades in addition to launches and may now help their gadgets for longer intervals of time.
Going one step additional, we’re additionally reusing the identical OS framework software program throughout a number of Qualcomm chipsets. This dramatically lowers the variety of OS framework and vendor implementation mixtures that Qualcomm has to help throughout their cellular platforms and leads to lowered engineering, growth, and deployment prices. The diagram under signifies how important the simplification is. From a software-support perspective, it is an altogether completely different scenario:
This variation is taking impact with all SoCs launching with Android 11 and later. By working carefully with Qualcomm to supply an prolonged interval of OS and safety updates, we’re trying ahead to delivering the most effective of Android to our customers quicker, and with larger safety for an prolonged time period.