The GEODE MFGPT code assumed that 32kHz was 32000 Hz while the boards
run on a 32.768 kHz digital watch crystal. In practise, it will not
change the timer's frequency as the skew was only 2.4%, but it
should provide more accurate intervals.
Signed-off-by: NWilly Tarreau <w@1wt.eu>
Signed-off-by: NAndres Salomon <dilinger@debian.org>
Signed-off-by: NJordan Crouse <jordan.crouse@amd.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

- uninline timer functions; the compiler knows better than we do
  whether or not to inline these.
- mfgpt_start_timer() had an unused 'clock' argument, drop it.

From both Jordan and myself.
Signed-off-by: NJordan Crouse <jordan.crouse@amd.com>
Signed-off-by: NAndres Salomon <dilinger@debian.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

The new "mfgptfix" boot command line option may be usd to fix MFGPT
timers on AMD Geode platforms when the BIOS has incorrectly applied
a workaround. TinyBIOS version 0.98 is known to be affected, 0.99
fixes the problem by letting the user disable the workaround.
Signed-off-by: NWilly Tarreau <w@1wt.eu>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

When we set the MFGPT timer tick, there is a chance that we'll
immediately assert an event.  If for some reason the IRQ routing
for this clock has been setup for some other purpose, then we
could end up firing an interrupt into the SMM handler or worse.

This rearranges the timer tick init function to initalize the handler
before we set up the MFGPT clock to make sure that even if we get
an event, it will go to the handler.

Furthermore, in the handler we need to make sure that we clear the
event, even if the timer isn't running.
Signed-off-by: NJordan Crouse <jordan.crouse@amd.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NIngo Molnar <mingo@elte.hu>
Tested-by: NArnd Hannemann <hannemann@i4.informatik.rwth-aachen.de>

Add support for an MFGPT clock event device; this allows us to use MFGPTs as
the basis for high-resolution timers.
Signed-off-by: NJordan Crouse <jordan.crouse@amd.com>
Signed-off-by: NAndres Salomon <dilinger@debian.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

This adds support for Multi-Function General Purpose Timers.  It detects the
available timers during southbridge init, and provides an API for allocating
and setting the timers.  They're higher resolution than the standard PIT, so
the MFGPTs come in handy for quite a few things.

Note that we never clobber the timers that the BIOS might have opted to use;
we just check for unused timers.
Signed-off-by: NJordan Crouse <jordan.crouse@amd.com>
Signed-off-by: NAndres Salomon <dilinger@debian.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>