DRA829V: EPWM: Linux support of module

Ahsan Hussain

Part Number: DRA829V

Hello TI team,

We're looking for EPWM module support on PSDKLA release 06.02.00 under Linux. We came across this thread https://e2e.ti.com/support/processors/f/791/p/898712/3323772#3323772 which tells us to configure EPWM in J721e device tree using the driver drivers/pwm/pwm-pru.c. The problem is that we can't find the corresponding PRU firmware to run with this driver under https://git.ti.com/cgit/pru-software-support-package/pru-software-support-package/tree/examples/j721e

Can you please let us know where can we find this firmware and whether our understanding about EPWM module on J721e is correct. If there's another driver available under Linux for EPWM then that would be helpful too.

Thanks

over 5 years ago

0 Vineet Roy over 5 years ago

TI__Mastermind 37435 points

Hi,

TI does not provide a PWM firmware in Linux, though it's enabled in kernel. See section 3.6.3.5 in this

There is an example in PDK which should act as a reference firmware for you. See this thread

Regards

Vineet

0 Ahsan Hussain over 5 years ago in reply to Vineet Roy

Intellectual 600 points

Hello Vineet,

Thanks for the quick response. I see in your shared document that PDK firmware and Linux driver configure PRU_ICSSG PWM module. Can you let me know if this is the same EPWM module in the main domain or something else?

Regards

0 Vineet Roy over 5 years ago in reply to Ahsan Hussain

TI__Mastermind 37435 points

This is not the PWM on the SoC, it's the PWM inside the PRU-ICSSG.

PRU-ICSSG is also part of Main domain, you can get more details in the section "Programmable Real-Time Unit Subsystem and Industrial Communication Subsystem" in TRM.

The PWM on SoC is described in the section "Enhanced Pulse Width Modulation (EPWM) Module" in TRM.

Regards

Vineet

0 Ahsan Hussain over 5 years ago in reply to Vineet Roy

Intellectual 600 points

Right. And would that mean that "Enhanced Pulse Width Modulation (EPWM) Module" isn't supported on either RTOS or Linux release?

0 Vineet Roy over 5 years ago in reply to Ahsan Hussain

TI__Mastermind 37435 points

Hi Ahsan,

There is a CSL baremetal example in PDK under pdk/packages/ti/csl/example/epwm/epwm_duty_cycle_test_app

You can use that as a reference

Regards

Vineet

Processors

Processors forum

DRA829V: EPWM: Linux support of module