Everything we know about the Pixel 7’s chip | #android | #security | #hacking | #aihp

We know quite a lot about the upcoming Google Pixel 7 and Pixel 7 Pro, but the chipset that will power those phones remains a little mysterious. Whether it was a benefit or a curse, Google’s sticking with its custom chips, and the Pixel 7 should debut a new incarnation of Tensor with the GS201. And, like last year, what little we do know is pretty unusual.

So far, leaks for the upcoming GS201 Tensor haven’t happened at the same rate they did for the original Tensor chipset. By just April of 2021, we knew quite a lot about the original GS101, but Google has managed to keep a tighter ship this year, limiting how much we and plumping out the spec table with plenty of “unknown” labels.

Specifications

For those that just want a table, here you go:

The second-gen Tensor GS201 will be made by Samsung on its 4nm node using what’s called panel-level packaging. This is a complicated way of saying the chips will be carved out of a square wafer rather than a round one, reducing waste. This likely won’t have much impact on the chip’s performance in actual devices, but it’s nifty and might reduce costs — potentially useful when we’re still in the middle of a chip shortage.

According to some recent diving into the boot logs of a Pixel 7 Pro prototype, the GS201 Tensor may still keep the 2+2+4 core cluster configuration that the original Tensor GS101 used, with two “super-big” cores, two more typical big cores, and four small cores. Details in the logs indicate that the small cores in the GS201 may still be Cortex A55s, given the log makes a note of a workaround implemented specifically for them. These are the same small cores used in the original GS101 Tensor chipset and a design that dates back to 2017.

It’s unclear what design the other cores in the GS201 might be. The last-gen Tensor used ARM Cortex-X1s for its “super-big” cores and A76s for its big cores. With chipset competitors having since moved on to the X2, we might see X2s for the big cores in the GS201, though that hasn’t been confirmed, and there are several generations of core designs Google or Samsung could choose to replace the A76 if they chose to.

Unsurprisingly, the GS201 will be paired with a Samsung-made modem again, according to details divined in earlier teardowns. The specific model spotted this time is the g5300b. If Samsung follows the same naming conventions it did on the prior Tensor, this might be tied to an Exnyos Modem 5300 variant, which hasn’t been formally announced yet.

Mass manufacturing for the chipset is expected to begin in June 2022, according to one report.

Other features

Smartphone chipsets aren’t just a list of cores; other details inside them can affect performance. One of the biggest reasons that Google elected to create its own chipset with the original Tensor was for enhanced machine learning applications. With the rise of ambient computing, so-called heterogeneous compute — which means pushing specialized workloads to different or customized pieces of hardware rather than just general-purpose CPUs — arguably has a bigger impact on perceived device performance than big single-threaded gains. It’s not just about one or two big benchmarks, but how we actually use our phones. More and more, that’s for things like speech recognition, translation, fancy camera features, AR/VR, and other more highly specialized workflows. And for that, you need more than a handful of recent ARM cores and a GPU.

The original Tensor included parts of Google’s HDRNet image processing pipeline in hardware, providing more specialization and direct performance for Google’s workloads than a general purpose ISP can. Google also gave it a dedicated security core (paired with a separate Titan M2 chip running “Trusty OS”). While details like these haven’t leaked for GS201 yet, you can likely bet that Google will continue to add these sorts of highly specialized changes. After all, features like these are the entire reason why a company would opt to create a custom smartphone chipset. Otherwise, Google would have just used something from Qualcomm, as it did in the past.

Details haven’t leaked yet, the GS201 will almost certainly have further optimizations and improvements in Google’s heterogeneous compute strategy, implementing other new camera and machine learning features in hardware where they can be done more quickly and efficiently. At I/O, all Google said about the upcoming chipset was that it will bring “even more AI-heavy breakthroughs and helpful personalized experiences across speech, photography, video, and security.” And while the original GS101 Tensor was heavily based on Samsung’s Exynos designs, we might see future models, like the GS201, diverge from this base over time and as Google’s requirements change.

It’s also worth pointing out that Google’s 2+2+4 core configuration is unique. So far, other chipset manufacturers haven’t followed in Google’s footsteps by including more than one “super-big” core. In an interview with Ars Technica’s Ron Amadeo, Google’s Phil Carmack (VP and GM of Google Silicon) said that this specific configuration was chosen to increase efficiency at “‘medium’ workloads” by being able to throw more resources at a task to do it quickly, returning to a low-power state faster:

“When it’s a steady-state problem where, say, the CPU has a lighter load but it’s still modestly significant, you’ll have the dual X1s running, and at that performance level, that will be the most efficient… You might use the two X1s dialed down in frequency so they’re ultra-efficient, but they’re still at a workload that’s pretty heavy. A workload that you normally would have done with dual A76s, maxed out, is now barely tapping the gas with dual X1s.”

Devices

The GS201 Tensor is expected to debut with the Pixel 7 series of phones, which will include the Pixel 7 and Pixel 7 Pro. If history is any indicator, we might see it also come to a future a-series Pixel (probably the Pixel 7a in 2023). Google has plans to release a Tensor-powered tablet as well, though it’s not clear if that will use the GS201 or some other chip, as it’s expected to land in 2023.

Another hardware codename has been tied to the GS201, but based on the name itself — Ravenclaw, a portmanteau of “Raven” (Pixel 6) and “claw” for the big cat names of the Pixel 7 series (Cheeta and Panther) — that might be a test device meant to include the Pixel 7 hardware inside a Pixel 6 body. Google used a similar naming schema for a Pixel 5 that had Pixel 6 internals.

Made by Google

With the GS201 reported entering production as of June 2022, the rate of leaks regarding the upcoming chip will likely pick up soon, and Google also has a history of taking charge during leak season to dribble out its own feature highlights. Odds are we’ll know more very soon. The longest we’ll have to wait, in either case, is until this fall’s anticipated Made by Google event when the Pixel 7 series is expected to launch.