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[Bernhard Froemel <817017@xxxxxxxxxxxxxxxxxx>]

@Tomodachi: What model do you have? I use a MBP 6,2 and there pure EFI
has problems on Linux: At least one year ago, there was no drivers from
Nvidia that supported the graphics adapter on systems in EFI mode..
although it *seems* to be only a small problem:
http://www.nvnews.net/vbulletin/showthread.php?t=162330

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https://bugs.launchpad.net/bugs/817017

Title:
  AHCI mode not restored during sleep-wakeup cycle

Status in Mactel Support:
  In Progress

Bug description:
  The SATA controller operates by default in IDE mode and there is no known EFI setting to override this behavior. Fortunately, it can be put into AHCI mode before the Linux kernel is booted (e.g. by Grub2 *) ).
  SSD disks perform much better in AHCI mode. On my laptop, both Intel SSD 320 and a Cruzial RealSSD C300 performed great in the beginning, but system responsiveness degraded soon to a point where system load was around 6 to 7 during updates (apt-get dist-upgrade) and second long freezes during normal work (e.g. browsing, responding to emails, heck - even when using vim in a terminal! ...).

  Unfortunately there is a drawback when putting the SATA controller into AHCI mode: AHCI is not restored during sleep-wakeup cycles and thus the system crashes badly after wakeup, because it suddently finds only an IDE controller.
  We need to patch (e.g. the SATA driver?) and check which mode the controller had been in, before the laptop was sent to sleep and restore the previous mode.

  *) How to put the SATA controller into AHCI mode [1]:
  MBP 6,2 (or any other 5 series/3400 series chipset based MBP)
  put this line before 'set root=...':
  setpci -d 8086:3b28 90.b=60
  (that command sets bit 5 and 6 on register 0x90 -- lookup Intel document number 322169 for details)

  [1] http://en.gentoo-wiki.com/wiki/Apple_Macbook_Pro

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