Qualcomm's MSM8660: Dual-Core ARM With Adreno 220 Graphics For The Performance-Hungry
Brian Dipert - May 21, 2011
Within my early-April cover story, ‘ARM versus Intel: a successful stratagem for RISC or grist for CISC’s tricks?‘, I discussed (among other SoCs) Qualcomm’s dual-core MSM8660. By means of review, the MSM8660 (befitting its prefix, which stands for Mobile Station Modem and is the successor to QSD aka Qualcomm Semiconductor) embeds a cellular baseband processor alongside the applications processor, and is based on the ‘Scorpion’ core versus the newer ‘Krait’ core conceptually unveiled at February’s Mobile World Congress show.
Krait may be coming soon, but Scorpion is here now, found in (for example) the pending-production HP TouchPad, first tablet fruit of that company’s last-summer acquisition of Palm. Here’s what I wrote about ‘Scorpion’ a month-back ago:
Architectural licensee Qualcomm developed the ARM Version 7-compliant Scorpion architecture, which, initially on 65-nm lithography, is currently in 45 nm. Scorpion achieved dual-core status in mid-2010 with the 1.2-GHz MSM8260 and MSM8660. Functionally, it [Scorpion] is an intermediary step between Cortex-A8 and Cortex-A9, supporting some but not all of Cortex-A9’s out-of-order instruction-execution capabilities. Scorpion-based Snapdragon SOCs also implement Cortex-A8- and A9-compliant floating-point and Neon SIMD engines. Scorpion implements the floating-point engine in a pipelined fashion, and the SIMD engine, at 128 bits, is twice as wide as the one in Cortex-A9.
The MSM8660 (the GSM variant; its MSM8260 sibling focuses on CDMA) is also the processing nexus of a developer-tailored handset design which Qualcomm initially supplied AnandTech a couple of months back. A month ago, Qualcomm decided to expand the reviewer list by five, and yours truly made the cut. Those of you with a spare $1,350 on your hands can now buy your own Mobile Development Platform from BSQUARE , containing (in my case, at least) the handset, USB and HDMI cables, a 3.3 Wh battery and two spares, and a charger:
The MDP handset has dimensions of 5.25″x2.5″x5/8″; here are some snapshots taken by (as you might be able to tell from the reflection in the first one) my Qualcomm-based Google Nexus One:
The MDP’s handset doesn’t have an active cellular subsystem because, as my Qualcomm PR contact explained, it hasn’t gone through carrier certification. It also runs a subset of the full Android 2.3 ‘experience’, although it’s slightly upgraded versus the version that AnandTech reviewed (Android 2.3.3 versus 2.3.2). However, its 2.4 GHz 802.11n Wi-Fi subsystem is seemingly fully functional, and I was also able to copy files to and from it (and otherwise access it) via the ADB (Android Debug Bridge) and other utilities included in the Android SDK.
Speaking of the Android SDK, I used its DDMS (Dalvik Debug Monitor) utility to snag a bunch of MDP screenshots. Don’t be concerned by their pinkish hue; it’s apparently due to a DDMS quirk which only affects some systems (I’d never encountered it before), and they look correct (black background, etc) on-handset. Here are the high-level settings options:
And here are the next-level Storage Settings:
and Dynamic Memory Manager (a setting option I’d never seen before) screens:
Here’s what About Phone says about the hardware and software:
And here’s the application suite which came with the MDP:
I feel compelled to note upfront that the software build wasn’t entirely stable (although it was generally quite solid), as this representative screenshot suggests:
Here’s what Qualcomm’s MDP documentation says:
Although the MSM8660 MDP is a fully supported development device, it uses an early development software release and therefore has a few limitations compared to commercial devices including: lack of full sensor support, non-optimized power control, occasional BT and Wi-FI instability, and limited support for HDMI terminals. Every effort was made to ensure the MDP you review fully supports our suggested benchmarks as well as any additional benchmarks you may wish to run. Subsequent software releases will continue to improve the overall stability, capability and power/performance of the MSM8660 platform. Because the platform is not power optimized, it is suggested that the unit remain plugged into the power adapter for sustained operation.
I suspect that the last sentence explains why Qualcomm bundle three batteries with the MDP. Here’s more on power management, important for you to understand versus the other hardware I benchmarked in this study (which has full power management enabled, albeit at a potential absolute performance tradeoff):
Because Qualcomm designs power management into every MSM design, “power savings” mode is the standard setting for all Snapdragon powered devices. Because these devices are designated for benchmarking, we have set the MDPs to “performance” mode which simply turns off normal power savings functions so that the true speed and performance of the processor can be measured accurately across multiple tests. Because power savings mode can impact different tests in different ways, running in performance mode allows more consistent results across all benchmarks. There are no additional adjustments required for benchmark testing on the MDP.
Continue reading ‘Qualcomm’s MSM8660: The Benchmark’s The Thing Wherein I’ll Crown The King‘…