4 ms·

Sorry, what do you mean? On a current MacBook Pro the memory is controlled by the CPU and the disk is attached to a PCIe root port also on the CPU. The "disk c

by mktmkr 7y ago

Sorry, what do you mean? On a current MacBook Pro the memory is controlled by the CPU and the disk is attached to a PCIe root port also on the CPU. The "disk controller" as such has moved into the disk.

deleted 7y ago
[deleted]
kalleboo 7y ago
The only way to access the soldered-in NAND storage is through the T2 chip, which encrypts everything on-the-fly with a unique burned-in AES key. The T2 also acts as the SSD controller, controlling the raw NAND chips. You can see this in an iMac Pro teardown, as the removeable "SSDs" in it only have flash chips on them, no controller. The T2 is not involved with memory access AFAIK though. As for I/O, it does handle the audio and camera access.
- mktmkr 7y ago
  Seems like a distinction without a difference. On any PC with an SSD there is "a controller" and "some NAND" the difference with the recent Apple gear is they've changed which part you can remove and replace, and which you cannot. My computer also has NAND you can only address through a dedicated controller that handles the encryption, but I don't think of it as indicative of a revolution.
  - dmix 7y ago
    I don’t think anyone buying a MacBook even knows about this or is calling it a revolution. The OP is the first I’ve heard make a big deal about this and the follow up comment is basically saying that he’s overstating the relevance to some ARM migration. I wouldn’t take random Internet comments too seriously.
  - robdachshund 7y ago
    OP just doesn't know what they are talking about. Welcome to HN. You are correct, the T2 chip is just a storage/memory controller. A lot of apple fans think it's a magical coprocessor. It's only there so they can use cheaper soldered ram and ssds and prevent repairs and upgrades. Good ol apple marketing at work.
  - kalleboo 7y ago
    Oh I'm not claiming like OP that this is some revolution that proves that a Mac is basically an ARM computer already. I'm just correcting your claim that "the disk controller has moved into the disk". There is no "disk". Rather the disk controller has moved into the security controller.
- dehrmann 7y ago
  That's consolidating some controllers. It probably has more to do having fewer parts, fewer vendors, and better repair lock-in. It's not really an architectural step towards replacing the CPU--it's a southbridge with better marketing.
  - josteink 7y ago
    > It's not really an architectural step towards replacing the CPU--it's a southbridge with better marketing. Except it locks out any OS not Windows or MacOS from using it. Southbridge didn’t have hardware mechanisms in place to intentionally lock Linux out from using the machine’s (rather expensive) internal storage.
    - sa1 7y ago
      It doesn't lock out linux from using it. They deviated from the NVMe spec, and it took time(and somebody to actually investigate) for the linux guys to figure it out: https://github.com/Dunedan/mbp-2016-linux/issues/71 https://github.com/Dunedan/mbp-2016-linux/issues/71 It's not a lockout by any means, and your next version of linux kernel will support it just fine(assuming the NVMe patches are merged).

by mktmkr 7y ago

deleted 7y ago

[deleted]

kalleboo 7y ago

The only way to access the soldered-in NAND storage is through the T2 chip, which encrypts everything on-the-fly with a unique burned-in AES key. The T2 also acts as the SSD controller, controlling the raw NAND chips. You can see this in an iMac Pro teardown, as the removeable "SSDs" in it only have flash chips on them, no controller. The T2 is not involved with memory access AFAIK though. As for I/O, it does handle the audio and camera access.

mktmkr 7y ago
Seems like a distinction without a difference. On any PC with an SSD there is "a controller" and "some NAND" the difference with the recent Apple gear is they've changed which part you can remove and replace, and which you cannot. My computer also has NAND you can only address through a dedicated controller that handles the encryption, but I don't think of it as indicative of a revolution.
- dmix 7y ago
  I don’t think anyone buying a MacBook even knows about this or is calling it a revolution. The OP is the first I’ve heard make a big deal about this and the follow up comment is basically saying that he’s overstating the relevance to some ARM migration. I wouldn’t take random Internet comments too seriously.
- robdachshund 7y ago
  OP just doesn't know what they are talking about. Welcome to HN. You are correct, the T2 chip is just a storage/memory controller. A lot of apple fans think it's a magical coprocessor. It's only there so they can use cheaper soldered ram and ssds and prevent repairs and upgrades. Good ol apple marketing at work.
- kalleboo 7y ago
  Oh I'm not claiming like OP that this is some revolution that proves that a Mac is basically an ARM computer already. I'm just correcting your claim that "the disk controller has moved into the disk". There is no "disk". Rather the disk controller has moved into the security controller.
dehrmann 7y ago
That's consolidating some controllers. It probably has more to do having fewer parts, fewer vendors, and better repair lock-in. It's not really an architectural step towards replacing the CPU--it's a southbridge with better marketing.
- josteink 7y ago
  > It's not really an architectural step towards replacing the CPU--it's a southbridge with better marketing. Except it locks out any OS not Windows or MacOS from using it. Southbridge didn’t have hardware mechanisms in place to intentionally lock Linux out from using the machine’s (rather expensive) internal storage.
  - sa1 7y ago
    It doesn't lock out linux from using it. They deviated from the NVMe spec, and it took time(and somebody to actually investigate) for the linux guys to figure it out: https://github.com/Dunedan/mbp-2016-linux/issues/71 https://github.com/Dunedan/mbp-2016-linux/issues/71 It's not a lockout by any means, and your next version of linux kernel will support it just fine(assuming the NVMe patches are merged).