[meta-xilinx] Zynq TTC usage by Linux

[Edward Wingate]

It looks like Linux is aware of TTC0 at least, from dmesg:
clocksource: ttc_clocksource: mask: 0xffff max_cycles: 0xffff,
max_idle_ns: 537538477 ns
ps7-ttc #0 at 9e808000, irq=18

And it is allocated with virtual memory mapping (/proc/vmallocinfo):
0x9e808000-0x9e80a000    8192 of_iomap+0x2c/0x34 phys=f8001000 ioremap

I can disable it in my device tree with:
ps7_ttc_0: ps7-ttc at f8001000 { compatible = "invalid"; }

Does anyone know what TTC0 would be used for?  Doesn't seem to be
critical as Linux stills boots and runs OK.  Thanks for your help.




On Thu, Oct 20, 2016 at 5:31 PM, Edward Wingate <edwingate8 at gmail.com> wrote:
> Does Linux use the Zynq's triple timer counters (TTC0/1) for anything
> by default?  Running in AMP mode with Linux on CPU0, I'm trying to use
> TTC0/TTC1 from CPU1, but don't seem to be able to. I don't see the
> TTCs' address space in /proc/iomem though.  Thanks for any help.
>
> Ed