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> You have two systems: A) T2 SOC B) Multiple chipsets working on its own. In both cases, it is a closed system. Sorry but I have to disagree with that. In the

> You have two systems: A) T2 SOC B) Multiple chipsets working on its own. In both cases, it is a closed system. Sorry but I have to disagree with that. In the latter case, it's not a closed system because the manufacturers of the chips (Intel, Realtek, etc) have publicly available datasheets describing in detail how to configure and use the chips. This allows people to write their own drivers for the hardware. The article says the T2 is implementing, at a minimum: * RAID * Sound * Storage encryption I have yet to see a public datasheet from Apple describing how a third party OS like Linux can utilize the features of the T2. You can get chipset datasheets from Intel which describe the registers, how to configure them, chipset IO pins, etc. [1] Similarly, you can get datasheets from audio chipset manufacturers that describe their chips in detail. [2] Same goes for many other components in a standard PC system, such as the SuperIO chip, TPM, USB controllers, etc. What Apple is doing is making more and more of their hardware proprietary, and (to my knowledge) not publishing a datasheet for these replacement components. This will actively harm anyone trying to run a non-Apple OS on the hardware. Sure, the component datasheets can't help you verify that the chip isn't doing something nefarious interally, but how is that any different than trusting Apple not to have any bugs or do anything nefarious in the T2? The replacement of components having publicly available datasheets with one that is a black box bothers me. [1] https://www.intel.com/content/dam/www/public/us/en/documents/datasheets/6-chipset-c200-chipset-datasheet.pdf https://www.intel.com/content/dam/www/public/us/en/documents... [2] http://realtek.info/pdf/ALC888_1-0.pdf http://realtek.info/pdf/ALC888_1-0.pdf

fermienrico 9y ago
Thanks for the detailed response. I understand your point completely - I agree that having datasheets publicly available certainly provides a level of transparency. The problem is that you're already trusting Apple by buying their system which is inherently closed. macOS is a completely closed OS with literally zero information about how these discrete chips may be used. The datasheet provides you with the API to the hardware, but you have no idea how Apple would be using the microphone for example - whether it is T2 chip or Realtek. GP's argument about "closed system" is moot when you're talking about using an inherently closed system - meaning, OS + Hardware. Also datasheets are what Realtek, for example, wants to publicize. How would you know if there is additional functionality built into the controller for backdoors, etc. that is deliberately left out of the datasheet?
- kogepathic 9y ago
  > The problem is that you're already trusting Apple by buying their system which is inherently closed. What? Perhaps we have different definitions of a closed system. I mean, even if you buy a Librium you're still getting a "closed" system because there are binary blobs such as microcode updates that run on it. The only way you can have a 100% open system is if it's open source hardware and something like RISCV (IMHO). Anyway, with a datasheet for the motherboard components there's a reasonable chance that someone could get coreboot working on the board. Without datasheets, it's nearly impossible to replace the system firmware with a different implementation. > macOS is a completely closed OS with literally zero information about how these discrete chips may be used. I think Apple is still releasing the XNU source, so you should be able to glean some information about the device functionality from the kernel module source code (assuming that is also published). [1] > The datasheet provides you with the API to the hardware, but you have no idea how Apple would be using the microphone for example - whether it is T2 chip or Realtek. So what? I never said I wanted to know how macOS is using the microphone. > GP's argument about "closed system" is moot when you're talking about using an inherently closed system - meaning, OS + Hardware. No, it's moot for your specific definition of a closed system. My definition of a "closed system" differs from yours. > Also datasheets are what Realtek, for example, wants to publicize. How would you know if there is additional functionality built into the controller for backdoors, etc. that is deliberately left out of the datasheet? You don't. Invest in tin-foil hat manufacturers. > I understand your point completely - I agree that having datasheets publicly available certainly provides a level of transparency. From your response I don't get the impression that you understand my point at all. My point was that Apple is replacing standard components used in PC designs since decades with a black box and not publishing a data sheet. I didn't argue that macOS was open. I didn't claim Apple should provide the VHDL files of the T2. I just said, if they're going to replace components with public datasheets with a magical black box lacking any public datasheet, I don't like that. My comment was specifically about how lacking a datasheet for the T2 is going to make using the computer with Linux (and without forcing the T2 into "terribly insecure" mode) much more difficult. [1] https://github.com/opensource-apple/xnu https://github.com/opensource-apple/xnu
  - fermienrico 9y ago

fermienrico 9y ago

Thanks for the detailed response. I understand your point completely - I agree that having datasheets publicly available certainly provides a level of transparency. The problem is that you're already trusting Apple by buying their system which is inherently closed. macOS is a completely closed OS with literally zero information about how these discrete chips may be used. The datasheet provides you with the API to the hardware, but you have no idea how Apple would be using the microphone for example - whether it is T2 chip or Realtek. GP's argument about "closed system" is moot when you're talking about using an inherently closed system - meaning, OS + Hardware. Also datasheets are what Realtek, for example, wants to publicize. How would you know if there is additional functionality built into the controller for backdoors, etc. that is deliberately left out of the datasheet?

kogepathic 9y ago
> The problem is that you're already trusting Apple by buying their system which is inherently closed. What? Perhaps we have different definitions of a closed system. I mean, even if you buy a Librium you're still getting a "closed" system because there are binary blobs such as microcode updates that run on it. The only way you can have a 100% open system is if it's open source hardware and something like RISCV (IMHO). Anyway, with a datasheet for the motherboard components there's a reasonable chance that someone could get coreboot working on the board. Without datasheets, it's nearly impossible to replace the system firmware with a different implementation. > macOS is a completely closed OS with literally zero information about how these discrete chips may be used. I think Apple is still releasing the XNU source, so you should be able to glean some information about the device functionality from the kernel module source code (assuming that is also published). [1] > The datasheet provides you with the API to the hardware, but you have no idea how Apple would be using the microphone for example - whether it is T2 chip or Realtek. So what? I never said I wanted to know how macOS is using the microphone. > GP's argument about "closed system" is moot when you're talking about using an inherently closed system - meaning, OS + Hardware. No, it's moot for your specific definition of a closed system. My definition of a "closed system" differs from yours. > Also datasheets are what Realtek, for example, wants to publicize. How would you know if there is additional functionality built into the controller for backdoors, etc. that is deliberately left out of the datasheet? You don't. Invest in tin-foil hat manufacturers. > I understand your point completely - I agree that having datasheets publicly available certainly provides a level of transparency. From your response I don't get the impression that you understand my point at all. My point was that Apple is replacing standard components used in PC designs since decades with a black box and not publishing a data sheet. I didn't argue that macOS was open. I didn't claim Apple should provide the VHDL files of the T2. I just said, if they're going to replace components with public datasheets with a magical black box lacking any public datasheet, I don't like that. My comment was specifically about how lacking a datasheet for the T2 is going to make using the computer with Linux (and without forcing the T2 into "terribly insecure" mode) much more difficult. [1] https://github.com/opensource-apple/xnu https://github.com/opensource-apple/xnu
- fermienrico 9y ago