ARM told us to expect some of the first 64-bit ARMv8 based SoCs to ship in 2014, and it looks like we're seeing just that. Today Qualcomm is officially announcing its first 64-bit SoC: the Snapdragon 410 (MSM8916). 

Given that there's no 64-bit Android available at this point, most of the pressure to go to 64-bit in the Android space is actually being driven by the OEMs who view 64-bit support as a necessary checkbox feature at this point thanks to Apple's move with the A7. Combine that with the fact that the most ready 64-bit IP from ARM is the Cortex A53 (successor to the Cortex A5/A7 line), and all of the sudden it makes sense why Qualcomm's first 64-bit mobile SoC is aimed at the mainstream market (Snapdragon 400 instead of 600/800).

I'll get to explaining ARM's Cortex A53 in a moment, but first let's look at the specs of the SoC:

Qualcomm Snapdragon 410
Internal Model Number MSM8916
Manufacturing Process 28nm LP
CPU 4 x ARM Cortex A53 1.2GHz+
GPU Qualcomm Adreno 306
Memory Interface 1 x 64-bit LPDDR2/3
Integrated Modem 9x25 core, LTE Category 4, DC-HSPA+

At a high level we're talking about four ARM Cortex A53 cores, likely running around 1.2 - 1.4GHz. Having four cores still seems like a requirement for OEMs in many emerging markets unfortunately, although I'd personally much rather see two higher clocked A53s. Qualcomm said the following about 64-bit in its 410 press-release:

"The Snapdragon 410 chipset will also be the first of many 64-bit capable processors as Qualcomm Technologies helps lead the transition of the mobile ecosystem to 64-bit processing.”

Keep in mind that Qualcomm presently uses a mix of ARM and custom developed cores in its lineup. The Snapdragon 400 line already includes ARM (Cortex A7) and Krait based designs, so the move to Cortex A53 in the Snapdragon 410 isn't unprecedented. It will be very interesting to see what happens in the higher-end SKUs. I don't assume that Qualcomm will want to have a split between 32 and 64-bit designs, which means we'll either see a 64-bit Krait successor this year or we'll see more designs that leverage ARM IP in the interim. 

As you'll see from my notes below however, ARM's Cortex A53 looks like a really good choice for Qualcomm. It's an extremely power efficient design that should be significantly faster than the Cortex A5/A7s we've seen Qualcomm use in this class of SoC in the past.

The Cortex A53 CPU cores are paired with an Adreno 306 GPU, a variant of the Adreno 305 used in Snapdragon 400 based SoCs (MSM8x28/8x26).

The Snapdragon 410 also features an updated ISP compared to previous 400 offerings, adding support for up to a 13MP primary camera (no word on max throughput however).

Snapdragon 410 also integrates a Qualcomm 9x25 based LTE modem block (also included in the Snapdragon 800/MSM8974), featuring support for LTE Category 4, DC-HSPA+ and the usual legacy 3G air interfaces.

All of these IP blocks sit behind a single-channel 64-bit LPDDR2/3 memory interface.

The SoC is built on a 28nm LP process and will be sampling in the first half of 2014, with devices shipping in the second half of 2014. Given its relatively aggressive schedule, the Snapdragon 410 may be one of the first (if not the first) Cortex A53 based SoCs in the market. 

A Brief Look at ARM's Cortex A53

ARM's Cortex A53 is a dual-issue in-order design, similar to the Cortex A7. Although the machine width is unchanged, the A53 is far more flexible in how instructions can be co-issued compared to the Cortex A7 (e.g. branch, data processing, load-store, & FP/NEON all dual-issue from both decode paths). 

The A53 is fully ISA compatible with the upcoming Cortex A57, making A53 the first ARMv8 LITTLE processor (for use in big.LITTLE) configurations with an A57

The overall pipeline depth hasn't changed compared to the Cortex A7. We're still dealing with an 8-stage pipeline (3-stage fetch pipeline + 5 stage decode/execute for integer or 7 for NEON/FP). The vast majority of instructions will execute in one cycle, leaving branch prediction as a big lever for increasing performance. ARM significantly increased branch prediction accuracy with the Cortex A53, so much that it was actually leveraged in the dual-issue, out-of-order Cortex A12. ARM also improved the back end a bit, improving datapath throughput. 

The result of all of this is a dual-issue design that's pushed pretty much as far as you can without going out-of-order. Below are some core-level performance numbers, all taken in AArch32 mode, comparing the Cortex A53 to its A5/A7 competitors:

Core Level Performance Comparison
All cores running at 1.2GHz DMIPS CoreMark SPECint2000
ARM Cortex A5 1920 - 350
ARM Cortex A7 2280 3840 420
ARM Cortex A9 r4p1 - - 468
ARM Cortex A53 2760 4440 600

Even ignoring any uplift from new instructions or 64-bit, the Cortex A53 is going to be substantially faster than its predecessors. I threw in hypothetical SPECint2000 numbers for a 1.2GHz Cortex A9 to put A53's performance in even better perspective. You should expect to see better performance than a Cortex A9r4 at the same frequencies, but the A9r4 is expected to hit much higher frequencies (e.g. 2.3GHz for Cortex A9 r4p1 in NVIDIA's Tegra 4i). 

ARM included a number of power efficiency improvements and is targeting 130mW single-core power consumption at 28nm HPM (running SPECint 2000). I'd expect slightly higher power consumption at 28nm LP but we're still talking about an extremely low power design.

I'm really excited to see what ARM's Cortex A53 can do. It's a potent little architecture, one that I wish we'd see taken to higher clock speeds and maybe even used in higher end devices at the same time. The most obvious fit for these cores however is something like the Moto G, which presently uses the 32-bit Cortex A7. Given Qualcomm's schedule, I wouldn't be surprised to see something like a Moto G update late next year with a Snapdragon 410 inside. Adding LTE and four Cortex A53s would really make that the value smartphone to beat.

POST A COMMENT

95 Comments

View All Comments

  • extide - Monday, December 09, 2013 - link

    I just picked up a ASUS Memo pad HD7 for my wife, and it has a quad A7 @ 1.2Ghz. I have been pretty impressed with how well it runs. Great little device. Looks like the A53 will be quite a bit more awesome.

    I do wish that table above included some high performance comparisons as well. It's nice to see the A9, but how about a Krait variant or two, and perhaps A15?
    Reply
  • FwFred - Monday, December 09, 2013 - link

    Between this press release, Qualcomm's CMO Anand Chandrasekher's comments, and no sign of 64-bit Krait, Qualcomm has quite the mixed marketing message regarding 64 bits.

    Qualcomm really can't claim any benefit to 64 bits without making a glaringly obvious hole in their higher end lineup. Another announcement pending? Wouldn't think so since they just announced the 805.
    Reply
  • Mil0 - Tuesday, December 10, 2013 - link

    805 will ship in 1H 2014, 410 in 2H 2014. It stands to reason that 805 is a stopgap before the 64 bit followup to krait is finished. If they're executing as well as they have been since krait's introduction, they would either have this 'krait2_64' ready for either the holiday season 2014 (unlikely, since that doesn't line up well with HW releases) or the new top devices of H1 2015 (S6, HTC one something). It could be that they make it for LG's next top device, perhaps the nexus 10 for 2H 2014. Reply
  • Drumsticks - Monday, December 09, 2013 - link

    Awesome! If this is the Snapdragon 410, and on the high end we only have an 805, I'll be looking forward to the Snapdragon 810 soon. Qualcomm's naming structure has improved lately but it's still a little bit complicated sometimes. Reply
  • phoenix_rizzen - Monday, December 09, 2013 - link

    This would have been the perfect opportunity to use the odd-numbered hundreds.

    As in, the Snapdragon 500s would be the 64-bit versions of the 400s. The S700s would be the 64-bit version of the S600s. And the S900s would be the 64-bit versions of the S800s.

    However, considering how overloaded S4 Pro has become lately, I don't expect to see anything logical come out of Qualcomm's naming.
    Reply
  • mtalinm - Monday, December 09, 2013 - link

    I keep telling my macolyte friends that 64-bit processors don't mean much unless you have >3GB of memory. Am I wrong on that? Reply
  • michael2k - Monday, December 09, 2013 - link

    You are here, because the 64 bit processors also have improved performance. Forget the 64 bitness and concentrate instead on the generation; the old generation of processors is slower than the next generation of processors, as per the norm, it just happens to be that the next generation of processors also happen to be 64 bit. You get more registers, better IPC, wider execution units, and lower power all mixed together. 64 bit is just frosting at that point. Reply
  • blanarahul - Monday, December 09, 2013 - link

    "more registers"
    Does this mean you will buy a car with 8 tyres v/s 4 tyres? I am sick of this MORE IS BETEER!!!! mentality. Most modern games don't even use 64 bit registers.

    "Lower power"
    Just because your car is wider than your motorbike doesn't mean it's more fuel efficient. Its the same with processors.

    Rest all points are vaild.
    Reply
  • BrooksT - Monday, December 09, 2013 - link

    More registers are better. Period. At least until ridiculous numbers.

    Registers can be thought of as a very fast cache. The more registers a CPU has, the less the compiler has to move data back and forth to/from memory.

    You seem to have confused quantity of registers with width of registers, and then conflated the power savings proposition with the 64 bitness. In fact, the power saving comes (in part) because the 32 bit ARM ISA evolved over time and has numerous tweaks for backwards compatibility, requiring more transistors and more power. The 64 bit ISA wipes that slate clean and implements only what is required. It's more efficient because it ditches those tweaks *and* is designed with learnings from the past decade in mind.

    64 bit isn't better in some abstract sense. 64 bit ARM is both higher performing and lower power than 32 bit ARM. And, as luck would have it, that's what we're talking about here.
    Reply
  • danbob999 - Monday, December 09, 2013 - link

    64 bit can perform better in some cases (when actually using more than 32 bits) but it uses more power because there is twice the logic involved when doing a basic addition such as 1+1. Reply

Log in

Don't have an account? Sign up now