path: root/arch/powerpc/include/asm/hw_irq.h
diff options
authorBenjamin Herrenschmidt <benh@kernel.crashing.org>2012-07-10 18:36:40 +1000
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>2012-07-10 19:16:07 +1000
commitbe2cf20a5ad31ebb13562c1c866ecc626fbd721e (patch)
tree939537de7ac05fc80b7b8c3588227c2b557b1687 /arch/powerpc/include/asm/hw_irq.h
parent2437fccfbfc83bcb868ccc7fdfe2b5310bf07835 (diff)
powerpc: More fixes for lazy IRQ vs. idle
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 <benh@kernel.crashing.org> CC: stable@vger.kernel.org [v3.4]
Diffstat (limited to 'arch/powerpc/include/asm/hw_irq.h')
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/hw_irq.h b/arch/powerpc/include/asm/hw_irq.h
index 6eb75b80488..92224b7fd70 100644
--- a/arch/powerpc/include/asm/hw_irq.h
+++ b/arch/powerpc/include/asm/hw_irq.h
@@ -125,6 +125,8 @@ static inline bool arch_irq_disabled_regs(struct pt_regs *regs)
return !regs->softe;
+extern bool prep_irq_for_idle(void);
#else /* CONFIG_PPC64 */
#define SET_MSR_EE(x) mtmsr(x)