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PCIe, power management, and problematic BIOSes

PCIe, power management, and problematic BIOSes

Posted Jun 29, 2011 20:06 UTC (Wed) by samroberts (subscriber, #46749)
In reply to: PCIe, power management, and problematic BIOSes by mjg59
Parent article: PCIe, power management, and problematic BIOSes

But how does the BIOS know whether ASPM works or not?

If it figures out from the devices, the kernel could do this, too.

Since you say the kernel can't do this reliably, I assume the BIOS authors have to hard-code this information about the devices? I guess, in theory, they should know, but it sounds pretty horrible.


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PCIe, power management, and problematic BIOSes

Posted Jun 29, 2011 20:13 UTC (Wed) by mjg59 (subscriber, #23239) [Link]

Because the BIOS has been tested with that set of hardware. This is typically a laptop problem, not a desktop one.

PCIe, power management, and problematic BIOSes

Posted Jun 29, 2011 20:24 UTC (Wed) by dlang (✭ supporter ✭, #313) [Link]

because the bios engineer hard-coded it to say if it works or not.

the BIOS isn't testing things and deciding it doesn't work, it's a hard-coded entry made by the BIOS programmer.

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