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The PSP and other improvements
Mullins and Beema's Platform Security Processor, or PSP, was already inside last year's Temash and Kabini silicon, but AMD waited until this generation to enable it—purportedly out of a desire to "more closely align with partner timelines and industry readiness." The PSP is made up of a 32-bit ARM Cortex-A5 processor core, a cryptographic co-processor, dedicated ROM and SRAM, some extra logic to enable secure booting, and a local memory interface that allows access system memory and resources.

In a nutshell, the PSP establishes an autonomous (and programmable) execution environment for secure applications. The nitty-gritty of it eludes us somewhat, but AMD provided this helpful summation:

We have and are working with a partner to enable the security kernel, which we then built into an enabled reference platform. That reference platform was then provided to [software vendors] with support from the security kernel partner and AMD to enable [software vendors] to adapt their software to use the hooks required to enter the secure environment. X86 applications dive through [the] Trusted Application Environment to get access to the ARM core.

The diagram below provides a higher-level overview of how the PSP comes into play:

Non-secure applications run on the x86 cores, while secure applications like anti-virus software, online banking, and biometric authentication can execute code on the PSP. Any malware running on the system should be constrained to the x86 environment, and it should therefore be unable to tamper with or hijack whatever data the PSP is processing.

AMD says this design enables "enterprise class security" and leverages an industry standard, ARM TrustZone, that also works on ARM-based smartphones. AMD expects at least four or five applications to leverage the PSP by the end of 2014. We're told the PSP will eventually become "pervasive" across the company's product line, as well. That should give developers an added incentive to support the feature in their applications.

Mullins and Beema have other tricks up their sleeves, too, in addition to the PSP and the new Turbo mojo.

On the memory controller front, faster DDR3-1866 RAM is supported on Beema variants aimed at mainstream notebooks, and AMD has added low-power mode that's "optimized for [the] lowest power DDR3-1333." That mode is supposed to cut power draw by 500 mW. Mullins and Beema don't support LPDDR3, like Intel's Bay Trail SoC, but AMD claims it's "getting most of the gains" of LPDRR3 with its new low-power mode.

Also, the company has used voltage-mod logic to reduce the power consumed by the display interface. AMD estimates the savings from that tweak at 200 mW for high-resolution panels.

Finally, there's Windows' connected standby mode—a critical feature for tablets that went untapped by Temash and Kabini. AMD tells us Mullins and Beema "can support connected standby." However, the company "has not seen high demand from customers," and it expects "the additional cost associated with the feature to impact how many total systems ultimately implement the feature." That cost stems from the various platform requirements associated with connected standby.

Our sense is that, while there are no technical obstacles to developing a connected standby driver for Mullins and Beema, AMD isn't feeling much pressure to do so right now. That could be because the company hasn't been able to secure tablet design wins for Mullins yet. Connected standby allows tablets to provide always-on connectivity in the same way that smartphones do, so one would imagine tablet makers would be eager to implement the feature, even if there is an added cost. Earlier this year, a CNet News story attributed the lack of 64-bit Bay Trail slates to the prioritization of 32-bit connected standby drivers by Intel and Microsoft.

The Mullins and Beema lineup
As we mentioned earlier, Mullins and Beema are based on the same silicon and differentiated through binning. AMD tells us the chips are "very carefully harvested and separated to fit their target market." The launch lineup consists of seven offerings in all: three that fall under the Mullins umbrella and four higher-wattage models that bear the Beema code name.

Model Radeon SDP TDP Cores CPU
clocks
L2
cache
size
GPU
ALUs
GPU
clocks
Max
DDR3L
speed
A10 Micro-6700T R6 2.8W 4.5W 4 1.2/2.2GHz 2MB 128 500MHz 1333MHz
A4 Micro-6400T R3 2.8W 4.5W 4 1.0/1.6GHz 2MB 128 350MHz 1333MHz
E1 Micro-6200T R2 2.8W 3.95W 2 1.0/1.4GHz 1MB 128 300MHz 1066MHz

Note the new branding. AMD has tacked "Micro" between the series indicator and the model number to demarcate Mullins. That's a little clearer than what we saw in the previous generation. Temash and Kabini were only differentiated by the first digits of their model numbers.

Interestingly, the lowest-wattage Mullins model actually has a higher TDP than the lowest-wattage chip from last year's Temash series. However, Mullins has a lower SDP, or scenario design power. In practice, AMD says, Mullins will be able to power high-performance fanless tablets, which Temash could not.

Mullins can also run at much higher clock speeds than Temash, thanks to Turbo and STAPM. Temash's processor cores maxed out at a 1GHz base speed and a 1.4GHz Turbo speed, but Mullins can range up to 2.2GHz. Perhaps not coincidentally, the slowest member of the Mullins series has the same CPU clock speeds as the fastest Temash chip.

Model Radeon TDP Cores CPU
clocks
L2
cache
size
GPU
ALUs
GPU
clocks
Max
DDR3L
speed
A6-6310 R4 15W 4 2.0/2.4GHz 2MB 128 800MHz 1866MHz
A4-6210 R3 15W 4 1.8GHz 2MB 128 600MHz 1600MHz
E2-6110 R2 15W 4 1.5GHz 2MB 128 500MHz 1600MHz
E2-6010 R2 10W 2 1.35GHz 1MB 128 350MHz 1333MHz

Turbo Core isn't as prevalent among these Beema processors—only the fastest of them supports it. Nevertheless, clock speeds have gone up, as has power efficiency. The fastest member of the mobile Kabini family runs at 2GHz, but it's saddled with a 25W thermal envelope. The new A6-6310 reaches the same base speed and runs even faster thanks to Turbo, all within a tighter 15W TDP.

We didn't get a chance to benchmark Beema, but we do have Mullins results on the next page. Press on to see them.