On Fri, Feb 28, 2014 at 02:07:58PM +0800, Li, Aubrey wrote: > On 2014/2/28 13:56, Matthew Garrett wrote: > > Probably, once we've got those patches landed (I've lost track of > > whether they're in 3.13 or aimed at 3.14) > > You didn't look the reference I quoted in the patch. > > It's stable if 32/64 bit linux call the corresponding 32/64bit EFI > runtime service. Matt Fleming's mixed mode is aiming at 3.15: > > http://git.kernel.org/cgit/linux/kernel/git/mfleming/efi.git/log/?h=mixed-mode
It's stable as long as you have the 1:1 mapping patches, which are different to the mixed mode patches. Otherwise it'll work on some hardware and crash on others. > > Mm. Not all x86 platforms support cf8/cf9 (Moorestown, for instance) and > > so it's theoretically possible that they'd put some different hardware > > there instead. But then, Moorestown probably has its own reboot code, so > > that may not matter? > > Yes, Moorestown has its own machine_ops. Instead of the system hanging > after issue "reboot" command, I think and suggest CF9 is worth to have a > try. Writing to arbitrary register addresses isn't a good plan if we're on a platform that might have different hardware there. > >> Reset register address: 0xCF9 > >> Value to cause reset: 0x6 > > > > Huh. But that's almost exactly what the PCI reboot code would do. Why > > does the PCI method work but the ACPI one fail? Does it really depend on > > ORing the original value with the reset value? Or is the timing just > > somehow marginal? > > reboot returns at: > > if (!(acpi_gbl_FADT.flags & ACPI_FADT_RESET_REGISTER)) > return; > > This is a ACPI bug or intention, who knows. Well, how about we figure that out? Is there a full acpi dump of one of these machines somewhere? -- Matthew Garrett | mj...@srcf.ucam.org -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
