Ohh I almost forgot that you can check the Overflow Flag Status Register (page 159 section 3.2.45).
On Tuesday, 11 March 2014 00:10:48 UTC, Paddu wrote: > > Hi Luis, > > Thank you so much. > Your information is very useful. > > Regards > Paddu > > On Tuesday, March 11, 2014 1:36:08 AM UTC+9, Luis wrote: >> >> Sorry, in my last reply it is *page 168 section 3.2.52*, not 3.5.52 >> >> On Monday, 10 March 2014 16:34:10 UTC, Luis wrote: >>> >>> Hi Paddu, >>> I believe it is a 32-bit register (I found no mention of 64-bit >>> registers in the c9 coprocessor). When it is overflown it resets to 0, in >>> my code I take this into account. It looks like you can generate overflow >>> interrupts (page 168 section 3.5.52) but I haven't used them. >>> >>> Hope this helps. >>> >>> Regards, >>> >>> Luis >>> >>> On Monday, 10 March 2014 15:00:26 UTC, Paddu wrote: >>>> >>>> >>>> Hi, >>>> >>>> Thank you for sharing very useful information. >>>> With your suggestions currently I am able to read the Cycle count using >>>> using this register. >>>> Please let me ask more question about CCNT register. >>>> >>>> Just for the confirmation, I would like to know is this a 32 bit >>>> register? or 64 bit? >>>> and what would happen if the count value is overflown, will the >>>> register reset to "0" ? >>>> >>>> Regards >>>> Paddu. >>>> >>>> >>>> On Tuesday, February 25, 2014 11:39:24 PM UTC+9, Luis wrote: >>>>> >>>>> Hi Paddu, >>>>> >>>>> The Cortex-A8 has a Performance Monitor Control Register (coprocessor >>>>> c9), you can check the documentation for the registers here (page 154, >>>>> section 3.2.42): >>>>> >>>>> http://infocenter.arm.com/help/topic/com.arm.doc.ddi0344k/DDI0344K_cortex_a8_r3p2_trm.pdf >>>>> >>>>> For a simple example of the code check this page: >>>>> http://stackoverflow.com/questions/3247373/how-to-measure-program-execution-time-in-arm-cortex-a8-processor >>>>> In there they use assembly to configure and read the registers for the >>>>> Cortex-A8, so it can be ported to any OS I believe. >>>>> >>>>> The Peformance Monitoring Unit is very cool, there's a ton of events >>>>> you can measure there, you can record up to 5 events (including the Clock >>>>> Cycles CCNT). >>>>> >>>>> >>>>> If you were using Linux it already has the implementation done for >>>>> you, you only need some libraries (found in >>>>> http://perfmon2.sourceforge.net/hw.html ). >>>>> >>>>> Hope this helps. >>>>> >>>>> Best Regards, >>>>> >>>>> Luis >>>>> >>>>> On Tuesday, 25 February 2014 03:02:31 UTC, Paddu wrote: >>>>>> >>>>>> Thank all for the kind reply. >>>>>> >>>>>> @liyaoshi-> I could find the link you have mentioned. >>>>>> >>>>>> @Grissiom -> Currently we are not using Linux, we are using >>>>>> Starterware. >>>>>> >>>>>> I shall see if we could implement this using a ASM code. >>>>>> >>>>>> >>>>>> On Tuesday, February 25, 2014 11:56:11 AM UTC+9, liyaoshi wrote: >>>>>>> >>>>>>> From this link , you can see >>>>>>> >>>>>>> readtsc() means this only support on x86 ,tsc register is 64bit >>>>>>> register and clock with main clock , on x86/64 this is can very precise >>>>>>> >>>>>>> On ARM, use generic PIT,(maybe you should write your own driver ) , >>>>>>> >>>>>>> only limit is almost PIT register is 32bit >>>>>>> >>>>>>> >>>>>>> 2014-02-25 10:49 GMT+08:00 Grissiom <chaos....@gmail.com>: >>>>>>> >>>>>>>> On Mon, Feb 24, 2014 at 10:26 PM, Paddu <pradeep....@gmail.com>wrote: >>>>>>>> >>>>>>>>> Hi, >>>>>>>>> >>>>>>>>> We need some advice in measuring Beaglebone CPU(Cortex-A8) clock >>>>>>>>> cycles. >>>>>>>>> Is there any way to measure the CPU cycles and use it inside the >>>>>>>>> program? >>>>>>>>> I have heard about "ccnt" register but don't know how exactly >>>>>>>>> could we use that in the program. >>>>>>>>> Please let me know if there is a reference or pointers on how to >>>>>>>>> implement the code. >>>>>>>>> >>>>>>>>> >>>>>>>> Do you want to measure cycles in Linux program or baremetal >>>>>>>> program? If you are on Linux, this link: >>>>>>>> >>>>>>>> http://halobates.de/modern-pmus-yokohama.pdf >>>>>>>> >>>>>>>> may help you. If not, read the PMU section in the ARM ARM. >>>>>>>> >>>>>>>> -- >>>>>>>> Cheers, >>>>>>>> Grissiom >>>>>>>> >>>>>>>> -- >>>>>>>> For more options, visit http://beagleboard.org/discuss >>>>>>>> --- >>>>>>>> You received this message because you are subscribed to the Google >>>>>>>> Groups "BeagleBoard" group. >>>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>>> send an email to beagleboard...@googlegroups.com. >>>>>>>> For more options, visit https://groups.google.com/groups/opt_out. >>>>>>>> >>>>>>> >>>>>>> -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
