linux-toradex.git/arch/powerpc/platforms/cell/pervasive.c, branch v3.4.78

powerpc: More fixes for lazy IRQ vs. idle

2012-07-16T16:03:49+00:00

commit be2cf20a5ad31ebb13562c1c866ecc626fbd721e upstream.

Looks like we still have issues with pSeries and Cell idle code
vs. the lazy irq state. In fact, the reset fixes that went upstream
are exposing the problem more by causing BUG_ON() to trigger (which
this patch turns into a WARN_ON instead).

We need to be careful when using a variant of low power state that
has the side effect of turning interrupts back on, to properly set
all the SW & lazy state to look as if everything is enabled before
we enter the low power state with MSR:EE off as we will return with
MSR:EE on. If not, we have a discrepancy of state which can cause
things to go very wrong later on.

This patch moves the logic into a helper and uses it from the
pseries and cell idle code. The power4/970 idle code already got
things right (in assembly even !) so I'm not touching it. The power7
"bare metal" idle code is subtly different and correct. Remains PA6T
and some hypervisor based Cell platforms which have questionable
code in there, but they are mostly dead platforms so I'll fix them
when I manage to get final answers from the respective maintainers
about how the low power state actually works on them.

Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

powerpc/cell: Cleanup sysreset_hack for IBM cell blades

2008-07-22T00:39:31+00:00

This patch adds a config option for the sysreset_hack used for
IBM Cell blades. The code is moves from pervasive.c into ras.c and
gets it's own init method.

Signed-off-by: Christian Krafft 
Signed-off-by: Arnd Bergmann 
Signed-off-by: Benjamin Herrenschmidt

[POWERPC] Replace remaining FUNCTION occurrences

2008-04-01T09:43:09+00:00

__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison 
Cc: Benjamin Herrenschmidt 
Signed-off-by: Andrew Morton 
Signed-off-by: Paul Mackerras

[POWERPC] cell: Move cbe_regs.h to include/asm-powerpc/cell-regs.h

2007-10-09T11:01:56+00:00

The new Cell EDAC driver needs that file, oprofile also does ugly
path tricks to get to it, it's time to move it to asm-powerpc. While
at it, rename it to be consistent with cell-pmu.h (and dashes look
nicer than underscores anyway).

Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Paul Mackerras

[POWERPC] cell: Support pinhole-reset on IBM cell blades

2007-08-25T06:58:26+00:00

The Cell Broadband Engine has a method of injecting a
system-reset-exception from an external source into the
operating system, which should trigger the regular behaviour
of entering xmon or kdump.

Unfortunately, the exception handler cannot distinguish it from
other interrupt causes by the SRR1 register, which gets used
for this on Power 6 and others.

IBM Blade servers that want to support triggering the
system reset exception using a pinhole button in the front
panel therefore use an extra register to determine the
reset cause.

Signed-off-by: Arnd Bergmann 

--
Signed-off-by: Paul Mackerras

powerpc: fixup hard_irq_disable semantics

2007-05-11T15:29:34+00:00

This patch renames the raw hard_irq_{enable,disable} into
__hard_irq_{enable,disable} and introduces a higher level hard_irq_disable()
function that can be used by any code to enforce that IRQs are fully disabled,
not only lazy disabled.

The difference with the __ versions is that it will update some per-processor
fields so that the kernel keeps track and properly re-enables them in the next
local_irq_disable();

This prepares powerpc for my next patch that introduces hard_irq_disable()
generically.

Signed-off-by: Benjamin Herrenschmidt 
Cc: Rusty Russell 
Cc: Paul Mackerras 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[POWERPC] cell: hard disable interrupts in power_save()

2006-12-04T09:40:21+00:00

With soft-disabled interrupts in power_save, we can
still get external exceptions on Cell, even if we are
in pause(0) a.k.a. sleep state.

When the CPU really wakes up through the 0x100 (system reset)
vector, while we have already started processing the 0x500
(external) exception, we get a panic in unrecoverable_exception()
because of the lost state.

This occurred in Systemsim for Cell, but as far as I can see,
it can theoretically occur on any machine that uses the
system reset exception to get out of sleep state.

Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Arnd Bergmann

[POWERPC] cell: use ppc_md->power_save instead of cbe_idle_loop

2006-10-25T04:20:22+00:00

This moves the cell idle function to use the default cpu_idle
with a special power_save callback, like all other platforms
except iSeries already do.

It also makes it possible to disable this power_save function
with a new powerpc-specific boot option "powersave=off".

Signed-off-by: Arnd Bergmann 
Signed-off-by: Paul Mackerras

[POWERPC] cell: update Cell BE register definitions

2006-10-25T04:20:21+00:00

There are a few definitions that are required by subsequent patches,
so add them here.

The original patch is from David Erb, but is significantly cleaned
up by Kevon Corry.

Cc: Kevin Corry 
Signed-off-by: Arnd Bergmann 
Signed-off-by: Paul Mackerras

Remove obsolete #include

2006-06-30T17:25:36+00:00

Signed-off-by: Jörn Engel 
Signed-off-by: Adrian Bunk