Previously there was a AMD specific quirk to handle the case of
AMD Fam10h MWAIT not supporting any C states. But it turns out
that CPUID already has ways to detectly detect that without
using special quirks.
The new code simply checks if MWAIT supports at least C1 and doesn't
use it if it doesn't. No more vendor specific code.
Note this is does not simply clear MWAIT because MWAIT can be still
useful even without C states.
Credit goes to Ben Serebrin for pointing out the (nearly) obvious.
Cc: "Andreas Herrmann" <andreas.herrmann3@amd.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Need this in the next patch in time_init and that happens early.
This includes a minor fix on i386 where early_intel_workarounds()
[which is now called early_init_intel] really executes early as
the comments say.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
According to AMD RDTSC can be synchronized through MFENCE.
Implement the necessary CPUID bit for that.
Cc: andreas.herrmann3@amd.com
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Some BIOSes set the C1E flag only on the second core. Print a warning so
the Firmware Toolkit can check for it.
mingo: fix C1E build bug on 32-bit
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
