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Comment by ginko | Hacker News Reader

Not really that surprising. Your average laptop nowadays probably has more ARM cores than x86 cores. They're in all kinds of peripherials like wifi controllers, power supplies, harddisk controllers, GPU job control, heck even AMD's recent APUs come with an integrated Cortex-A5.[1] ARM cores are everywhere, people just don't know about it.

[1]http://www.anandtech.com/show/6007/amd-2013-apus-to-include-...

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Laptops have what is known as an "embedded controller" to handle peripherals like keyboard/touchpad, power management, and fan control. Most of them seem to be low-power 8/16-bit MCUs like 8051 and H8S, but I wouldn't be surprised if newer ones use ARM too.

...and don't forget Intel ME, which is not ARM but another processor in the system.

Most Chromebooks have embedded controller running on ARM specifically.

https://www.chromium.org/chromium-os/ec-development

System-on-chips (most big chips these days) are so complex they usually have the same thing one level deeper: On chip embedded controllers, often an mcu.

You might find that 'one arm chip' has many independent arm cpu cores carrying out different functions mostly completely hidden from end user behind firmware or rom

Amusingly enough, the embedded controller on some of the newer Allwinner ARM SoCs is apparently OpenRISC of all things. Guess it saved them some licensing fees.

New ME is apparently a SPARCv8 core. Older ones were ARC.

Intel platforms also had an ARC processor (they approximately cater the same markets as ARM minus mobile) for years in the ME.

AMD does the same thing with an ARM core.

Practically all peripherals contain at least one programmable processor.

Remote management / IPMI also usually works with an entirely separate ARM computer that's integrated with the main computers graphics unit -- basically a shared framebuffer, just in hardware.

Fun fact: ARC derives originally from the SuperFX inside some SNES cartridges like Star Fox.

any source for this? should be an interesting Read

https://en.wikipedia.org/wiki/Synopsys#ARC_International

It blows my mind that the Super FX not only survived the collapse of Argonaut but went on to become so widely adopted by companies that presumably could make their own tiny microprocessors.

So cool.

ARC had been split out into Argonaut Technology Ltd. long before Argonaut Software hit the buffers.

The success of the SuperFX chip opened doors for future work, but nothing from the SuperFX was carried over - it was 16 bit, with a compact instruction encoding, a gate level design using ECAD.

A string of graphics hardware projects followed with a wide range of requirements, targeting 'interesting' (ie: cheapest) processes/standard cell libraries. These were all VHDL, and a flexible 32 bit embedded risc control processor emerged as a common theme.

The configurability and robustness in the face of sketchy ecad toolchains made it a very saleable thing in it's own right.

> Intel platforms also had an ARC processor

That is true for older designs. But didn't Intel switch from ARC to SPARC for their ME core not that long ago? Discussed here a while back:

https://news.ycombinator.com/item?id=8813029

They're ARC cores, not SPARC. That thread is full of misunderstandings of a PDF version of a presentation that incorrectly concluded it was looking at a SPARC core when it was looking at a newer model ARCcompact

SPARC would be a terrible mismatch for what Intel wants out of its ME

AMD CPUs and GPUs both have an integrated ARC processor that mainly deals with power management.

Whenever this topic occurs, I send this in http://spritesmods.com/?art=hddhack&page=1

Ubiquitous com...fusion.

I love that.

I had a hard drive that had a firmware fault, and I repaired it using a USB-Serial converter, taking the pcb off the drive to temporarily mask off a connector, and then issuing a couple of commands. http://superuser.com/questions/365999/how-do-i-recover-data-...

http://superuser.com/questions/365999/how-do-i-recover-data-...

You must have suffered full mental god complex for a few days after that. I'm happy when I succeed in creating a bootable live iso usb key with grub2...

I call that an ego boner.

Thank you. That is one of the best hacks I've read. Very enjoyable.

Don't forget that many (if not most) SSDs are dual core ARM chips.

Often more than just two cores. Samsung's latest PCIe controller increased from three to five ARM cores, and most of their SATA SSD controllers have also been 3-core designs. Phison's mainstream SATA SSD controller has four cores.

What is the AMD equivalent of Intel's open-source tboot for trusted execution, to take advantage of ARM TrustZone on an AMD processor?

Hell some (all?) Macbooks even have FPGAs

What is the FPGA used for?

I'm not sure about the FPGAs the parent comment is specifically talking about, but often FPGAs in general purpose devices are used just for glue logic - that is, buffering and interfacing between different types of busses.

To allow for fixes in the field. You can't really repair hardware once it is shipped, but you can reprogram an FPGA to fix a problem in a bunch of logic so it is better to have that logic in an FPGA than to have it hardwired.

Don't be surprised if an upgrade to your OS also reprograms that FPGA.

I was surprised about that and looked for a source. Here it is: https://www.ifixit.com/Teardown/MacBook-Pro-15-Inch-Unibody-...

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