imx6 ipg per clocks

hiromiyokoo — Tue, 17 Oct 2017 11:02:51 GMT

Hello,

I'm updating the device tree of my custom board, using iMX6QDL, from Linux 3.14 to Linux 4.1, and I found this change, that appears to be made by AnsonHuang‌:

diff --git a/arch/arm/boot/dts/imx6qdl.dtsi b/arch/arm/boot/dts/imx6qdl.dtsi
 index 70d7207..8de2801 100644 --- a/arch/arm/boot/dts/imx6qdl.dtsi
 +++ b/arch/arm/boot/dts/imx6qdl.dtsi @@ -401,8 +401,9 @@
                      reg = <0x02098000 0x4000>;
                      interrupts = <0 55 IRQ_TYPE_LEVEL_HIGH>;
                      clocks = <&clks IMX6QDL_CLK_GPT_IPG>, 
-                          <&clks IMX6QDL_CLK_GPT_IPG_PER>;
 -                    clok-names = "ipg", "per";
 +                          <&clks IMX6QDL_CLK_GPT_IPG_PER>,
 +                          <&clks IMX6QDL_CLK_GPT_3M>;
 +                    clock-names = "ipg", "per", "osc_per";

If I apply this patch to my board the debug output changes this way:
BEFORE PATCH:
mxc_clocksource_init 66000000
Switching to timer-based delay loop, resolution 15ns
sched_clock: 32 bits at 66MHz [...]
AFTER PATCH:
mxc_clocksource_init 3000000
Switching to timer-based delay loop, resolution 333ns
sched_clock: 32 bits at 3000kHz [...]

My questions are:

- Should I keep this change?

- Will Linux (or my applications) run slower with this change?

- What are these clocks (ipg, per, osc_per) used for?

Sorry if my questions are trivial...

Kind Regards,

Roberto

Re: imx6 ipg per clocks

gusarambula — Tue, 24 Oct 2017 17:19:41 GMT

Hello, AnsonHuang

Would you please help us answer these questions?

Regards,

Gustavo

i.MX ProcessorsのトピックRe: imx6 ipg per clocks

imx6 ipg per clocks

Re: imx6 ipg per clocks