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From: Bjorn Helgaas <bjorn.helgaas@hp.com>
To: Feng Tang <feng.tang@intel.com>
Subject: EFI runtime-services on x86_64
Date: Fri, 30 Jul 2010 14:58:48 -0600
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Hello Feng,

Can you educate me about your commit 772be899bc, "86: Make EFI RTC
function depend on 32bit again"?

It adds "#ifdef CONFIG_X86_32" to avoid using efi_get_time() and
efi_set_rtc_mmss(), but there's no explanation of *why* those services
only work on 32-bit.

Is this an EFI spec limitation?  Do the other EFI runtime services
work on 64-bit, since you didn't touch them?  Or do we just not use
any of the others?

Is this something that can be fixed, so we *could* use efi_get_time()
on 64-bit if we did some work?  What would need to be done?

Bjorn