Messages in this thread | | | Subject | Re: [PATCH 1/3] Powerpc: mpc85xx: refactor the PM operations | From | Scott Wood <> | Date | Wed, 5 Aug 2015 21:57:28 -0500 |
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On Wed, 2015-08-05 at 18:11 +0800, Chenhui Zhao wrote: > On Tue, Aug 4, 2015 at 4:26 AM, Scott Wood <scottwood@freescale.com> > wrote: > > On Mon, 2015-08-03 at 19:32 +0800, Chenhui Zhao wrote: > > > > > > > > > On Sat, Aug 1, 2015 at 7:59 AM, Scott Wood <scottwood@freescale.com> > > > wrote: > > > > > > > > > > Could you explain irq_mask()? Why would there still be IRQs > > > destined > > > > for > > > > this CPU at this point? > > > > > > This function just masks irq by setting the registers in RCPM (for > > > example, RCPM_CPMIMR, RCPM_CPMCIMR). Actually, all irqs to this CPU > > > have been migrated to other CPUs. > > > > So why do we need to set those bits in RCPM? Is it just caution? > > Setting these bits can mask interrupts signalled to RCPM from MPIC as a > means of > waking up from a lower power state. So, cores will not be waked up > unexpectedly.
Why would the MPIC be signalling those interrupts if they've been masked at the MPIC?
-Scott
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