linux-toradex.git/arch/x86/platform/uv, branch v3.4.82

x86/uv: Fix UV2 BAU legacy mode

2012-06-17T18:21:23+00:00

commit d5d2d2eea84b0d8450b082edbc3dbde41fb8bfd8 upstream.

The SGI Altix UV2 BAU (Broadcast Assist Unit) as used for
tlb-shootdown (selective broadcast mode) always uses UV2
broadcast descriptor format. There is no need to clear the
'legacy' (UV1) mode, because the hardware always uses UV2 mode
for selective broadcast.

But the BIOS uses general broadcast and legacy mode, and the
hardware pays attention to the legacy mode bit for general
broadcast. So the kernel must not clear that mode bit.

Signed-off-by: Cliff Wickman 
Link: http://lkml.kernel.org/r/E1SccoO-0002Lh-Cb@eag09.americas.sgi.com
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

x86/UV: Lower UV rtc clocksource rating

2012-02-20T08:07:56+00:00

Lower the rating of the UV rtc clocksource to just below that of
the tsc, to improve performance.

Reading the tsc clocksource has lower latency than reading the
rtc, so favor it in situations where it is synchronized and
stable.  When the tsc is unsynchronized, the rtc needs to be the
chosen clocksource.

Signed-off-by: Dimitri Sivanich 
Cc: John Stultz 
Cc: Jack Steiner 
Link: http://lkml.kernel.org/r/20120217141641.GA28063@sgi.com
Signed-off-by: Ingo Molnar

x86/uv: Fix uninitialized spinlocks

2012-01-26T09:58:34+00:00

Initialize two spinlocks in tlb_uv.c and also properly define/initialize
the uv_irq_lock.

The lack of explicit initialization seems to be functionally
harmless, but it is diagnosed when these are turned on:

        CONFIG_DEBUG_SPINLOCK=y
        CONFIG_DEBUG_MUTEXES=y
        CONFIG_DEBUG_LOCK_ALLOC=y
        CONFIG_LOCKDEP=y

Signed-off-by: Cliff Wickman 
Cc: 
Cc: Dimitri Sivanich 
Link: http://lkml.kernel.org/r/E1RnXd1-0003wU-PM@eag09.americas.sgi.com
[ Added the uv_irq_lock initialization fix by Dimitri Sivanich ]
Signed-off-by: Ingo Molnar

Merge remote-tracking branch 'linus/master' into x86/urgent

2012-01-19T20:56:50+00:00

x86/UV2: Add accounting for BAU strong nacks

2012-01-17T08:09:59+00:00

This patch adds separate accounting of UV2 message "strong
nack's" in the BAU statistics.

Signed-off-by: Cliff Wickman 
Link: http://lkml.kernel.org/r/20120116212238.GF5767@sgi.com
Signed-off-by: Ingo Molnar

x86/UV2: Ack BAU interrupt earlier

2012-01-17T08:09:57+00:00

This patch moves the ack of the BAU interrupt to the beginning
of  the interrupt handler so that there is less possibility of a
lost interrupt and slower response to a shootdown message.

Signed-off-by: Cliff Wickman 
Link: http://lkml.kernel.org/r/20120116212146.GE5767@sgi.com
Signed-off-by: Ingo Molnar

x86/UV2: Remove stale no-resources test for UV2 BAU

2012-01-17T08:09:56+00:00

This patch removes an unnecessary test for a
no-destination-resources-available condition that looks like a
destination timeout in UV1, but is separately distinguishable in
UV2.

Signed-off-by: Cliff Wickman 
Link: http://lkml.kernel.org/r/20120116212050.GD5767@sgi.com
Signed-off-by: Ingo Molnar

x86/UV2: Work around BAU bug

2012-01-17T08:09:54+00:00

This patch implements a workaround for a UV2 hardware bug.
The bug is a non-atomic update of a memory-mapped register. When
hardware message delivery and software message acknowledge occur
simultaneously the pending message acknowledge for the arriving
message may be lost.  This causes the sender's message status to
stay busy.

Part of the workaround is to not acknowledge a completed message
until it is verified that no other message is actually using the
resource that is mistakenly recorded in the completed message.

Part of the workaround is to test for long elapsed time in such
a busy condition, then handle it by using a spare sending
descriptor. The stay-busy condition is eventually timed out by
hardware, and then the original sending descriptor can be
re-used. Most of that logic change is in keeping track of the
current descriptor and the state of the spares.

The occurrences of the workaround are added to the BAU
statistics.

Signed-off-by: Cliff Wickman 
Link: http://lkml.kernel.org/r/20120116211947.GC5767@sgi.com
Cc: 
Signed-off-by: Ingo Molnar

x86/UV2: Fix BAU destination timeout initialization

2012-01-17T08:09:53+00:00

Move the call to enable_timeouts() forward so that
BAU_MISC_CONTROL is initialized before using it in
calculate_destination_timeout().

Fix the calculation of a BAU destination timeout
for UV2 (in calculate_destination_timeout()).

Signed-off-by: Cliff Wickman 
Link: http://lkml.kernel.org/r/20120116211848.GB5767@sgi.com
Cc: 
Signed-off-by: Ingo Molnar

x86/UV2: Fix new UV2 hardware by using native UV2 broadcast mode

2012-01-17T08:09:51+00:00

Update the use of the Broadcast Assist Unit on SGI Altix UV2 to
the use of native UV2 mode on new hardware (not the legacy mode).

UV2 native mode has a different format for a broadcast message.
We also need quick differentiaton between UV1 and UV2.

Signed-off-by: Cliff Wickman 
Link: http://lkml.kernel.org/r/20120116211750.GA5767@sgi.com
Cc: 
Signed-off-by: Ingo Molnar