On Tuesday 20 of August 2013 09:33:31 Stephen Boyd wrote: > On 08/20/13 09:11, Tomasz Figa wrote: > > Sometimes it is necessary to fix interrupt affinity to an offline CPU, > > for example in initialization of local timers. This patch modifies > > .set_affinity() operation of irq-gic driver to fall back to any > > possible > > CPU if no online CPU can be found in requested CPU mask. > > > > This fixes broken Exynos4210 support since commit > > > > ee98d27df6 ARM: EXYNOS4: Divorce mct from local timer API > > > > caused by timer initialization code unable to set affinity for local > > timer interrupts. > > Care to elaborate further? I don't see how the interrupt affinity is set > for a CPU that isn't online because the mct code runs on the CPU that > the affinity is being set to. Well, please look at secondary_start_kernel() in arch/arm/kernel/smp.c [1]. You can see that notify_cpu_starting() (line 348) that fires the notifier registered in MCT driver is called before set_cpu_online() (line 359) that marks the CPU as online. Also notice that, originally, local timer initialization was happening after set_cpu_online() - see line 365. [1] - http://lxr.free-electrons.com/source/arch/arm/kernel/smp.c?a=arm#L312 Best regards, Tomasz -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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