AM5728: DSP1 clock on clkout3

Hi Indra,

What value you have in CTRL_CORE_PAD_XREF_CLK3 register? Make sure it is setup for clkour3 mode.

You can also try to set CM_CLKSEL_CLKOUTMUX0 register to export sys_clk1 signal and check if you will be able to see that signal. If yes, then you need to check if DSP1 is ON and operational.

Regards,
Pavel

The CTRL_CORE_PAD_XREF_CLK3 register has mode set to clkout3

Indra,

Can you also check the value of CTRL_CORE_PAD_XREF_CLK3[18] XREF_CLK3_INPUTENABLE ? If 1, can you set it as output (write 0) and test again, do you see the DSP1 clock output?

I would also suggest you to to first test to export sys_clk1 (20MHz) signal on clkout3 pin, once successful, you can proceed with dsp1 clock. Are you able to measure the sys_clk1 clock on clkout3 pin? Below registers are related to exporting sys_clk1 on clkout3 pin:

CM_CLKSEL_SYS_CLK1_CLKOUTMUX
CM_CLKSEL_CLKOUTMUX0

Check also if below e2e threads will be in help:

e2e.ti.com/.../1718034
e2e.ti.com/.../571167
e2e.ti.com/.../651530



Here's my summary:

1. The pin muxing must be correctly configured for the pin you're trying to use.

2. The clock you want to output (MPU_DCLK, DSP_GCLK, etc.) should be selected through the CM_CLKSEL_CLKOUTx register where x = 1,2,3.

3. The clock must be ungated. This procedure varies by clock.
a.CLKOUT1 can be ungated by setting CM_COREAON_CLKOUTMUX1_CLKCTRL[OPTFCLKEN_CLKOUTMUX1_CLK] = 1.
b.CLKOUT2 can be ungated by setting CM_COREAON_CLKOUTMUX2_CLKCTRL[OPTFCLKEN_CLKOUTMUX2_CLK] = 1.
c.CLKOUT3 can be ungated by configuring any of the CM_IPU_TIMERx_CLKCTRL registers where x = 5, 6, 7, or 8. Specifically, you should set CLKOUT = 0xB (CLKOUT3_CLK) and MODULEMODE = 2 (enabled).

4. If you’re trying to output the MPU clock specifically then you need to also set a bit called HWOBS_MACRO_ENABLE. Note that there’s a /4 in the path. So whatever you’ve configured in CM_CLKSEL_MPU_GCLK_CLKOUTMUX will apply, and additionally another /4.


Regards,
Pavel

Hi,

I was able to get the SYS_CLK1 (20 MHz) on clkout3 pin. But DSP clock on clokout3 pin is not coming.

Best Regards
Indra

Hi,

I was able to get the SYS_CLK1 (20 MHz) on clkout3 pin. But DSP clock on clokout3 pin is not coming.

Best Regards
Indra

HI Pavel,

I was able to get the DSP clock on clkout3 pin. There was error in the register configuration. Thank you for your support.

Regards

Indra