topic Re: i.MX6QP GPU frequency issue in i.MX Processors

i.MX6QP GPU frequency issue

andrzejdziedzic — Wed, 15 Mar 2017 10:34:59 GMT

Hi,

I have a custom board using i.MX6QP and Android M6.0.1_2.0.0.

I observe some strange issue while trying to reduce GPU speed in the file: kernel_imx/drivers/mxc/gpu-viv/hal/kernel/arch/gc_hal_kernel_hardware.c

1. If powerOnFscaleVal is set to 1 at start (line 1225) then performance lowers dramatically, GPU is VERY slow.

2. If powerOnFscaleVal is set to 64 at start, then later changed 1 using a function SetFscaleValue, then performance lowers only a bit (simple animations are still smooth).

What is the difference between those two cases?

Re: i.MX6QP GPU frequency issue

Bio_TICFSL — Fri, 17 Mar 2017 17:36:06 GMT

Hi,

You may need to check the CPU/GPU changes speed every time you change that value, for clock frequencies one can use dump-clocks.sh utility provided in

Re: increase CPU/GPU frequency on iMX6 Solo

If you like to suspend the GPU or keep it always active, one can set parameter in ../gc_hal_options.h, gcdPOWEROFF_TIMEOUT to zero.

kernel_imx/gc_hal_options.h at master · boseji/kernel_imx · GitHub

Hope this helps

Re: i.MX6QP GPU frequency issue

andrzejdziedzic — Tue, 28 Mar 2017 08:29:03 GMT

You may need to check the CPU/GPU changes speed every time you change that value, for clock frequencies one can use dump-clocks.sh utility provided in
Re: increase CPU/GPU frequency on iMX6 Solo

Which clocks should I observe? I observed gpu clocks but I see no difference.

For example the value of /sys/kernel/debug/clk/gpu3d_shader/clk_rate is always 720000000, no matter what powerOnFscaleVal is set.

It looks like an initial rate, not the curent one.

Where can I check the real GPU frequency?

If you like to suspend the GPU or keep it always active, one can set parameter in ../gc_hal_options.h, gcdPOWEROFF_TIMEOUT to zero.
kernel_imx/gc_hal_options.h at master · boseji/kernel_imx · GitHub

When GPU goes to the suspend state?