On 09/20/2012 11:59 AM, Paul Walmsley wrote: > Hi > > On Mon, 10 Sep 2012, Jon Hunter wrote: > >> From: Ming Lei <ming.lei@xxxxxxxxxxxxx> >> >> For OMAP4430 there are no dedicate PMU interrupts, however, PMU events can be >> routed to via the CTI IRQs. This allows tools such as PERF and OPROFILE to work >> on OMAP4430. >> >> The idea is from Woodruff Richard in the disscussion about "Oprofile on >> Pandaboard / Omap4" on pandaboard@xxxxxxxxxxxxxxxx. >> >> Ming's original patch was called "arm: omap4: support pmu" [1] and has been >> renamed and modified by Jon Hunter. There main differences from the original >> patch are ... >> >> 1. Instead of only configuring the CTI interrupt once during boot, the >> interrupts are configured everytime the the PMU is used. The reason for this >> is because during power transitions the CTI logic state will be lost and so >> we will need to configure the interrupts everytime they are used. This is >> accomplished by using the PM runtime callbacks which will be called whenever >> the PMU is used. >> 2. Assign the PMU events to different cross triggering channels. This prevents >> a single PMU event generating interrupts to both CPUs and hence can cause >> spurious interrupts to occur. Reported by Ming [2]. >> >> [1] http://marc.info/?l=linux-arm-kernel&m=132227620816504&w=2 >> [2] http://permalink.gmane.org/gmane.linux.linaro.devel/10532 > > Spent some time with this one here. At this point I don't think I can > queue it. It's got hardcoded IRQ numbers and address information for the > CTI, and mixes the CTI and PMU programming. A few months ago we might > have gotten away with this, but now it seems best to do this one cleanly. > Probably the CTI control should be moved off into mach-omap2/omap4-cti.c > or somewhere into drivers/ if possible. So let's revisit this for 3.8. Ok, no problem, I can't say I was thrilled with the implementation so probably best to re-think some more. How about adding the cross-trigger interface as a hwmod for omap4 to store the base address and interrupt number? Cheers Jon -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
