• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 97 subscribers
  • Views 501 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

Turning off DSP on OMAPL138 using PSC

Thomas Price7137
Intellectual 625 points

Other Parts Discussed in Thread: OMAPL138

I was considering bringing up my OMAPL138 with just the ARM on and the DSP disabled at initialization. One thought I was having regarding this issue was to specifically turn off the DSP via the PSC. I was going through the PSC and PLL reference and saw the following:

 

#define LPSC_DSP         15  /*PSC0*/

 

Would it be possible to just disable this PSC?

I’m just curious if that would have a negative effect on other peripherals I might still need through the ARM.

  • 0
    TI__Guru* 85155 points

    Thomas Price said:
    Would it be possible to just disable this PSC?

    Yes, the OMAPL138 system guide has the step sequence on how to turn off the DSP clocks via PSC from the ARM side. Unfortunately there isn't a canned example available in our current software collateral for you to leverage.

    Thomas Price said:
    I’m just curious if that would have a negative effect on other peripherals I might still need through the ARM.

    From a device architecture standpoint none, because the OMAPL1x devices offer users the flexibility to program/control/access all periperhals from both ARM or DSP side. So you can surely turn of the DSP clock if it makes sense for your application and power budget.

    Please also note that while we have not yet completed the OMAPL138 power estimation spreadsheet, there is one available now for OMAPL137 spreadsheet,while the power consumption and power management features on these devices are different , you can definitely use this to comprehend the relative power savings  between clocking off the DSP clock via PSC (through ARM side) vs putting the DSP in IDLE using the c674x Power Down controller (part of the DSP megamodule) at a given frequency and core voltage (Note OMAPL137 does not support CVDD 1.1/1.0V, but I think you should still find this handy).

    http://processors.wiki.ti.com/index.php/OMAP-L137_Power_Consumption_Summary

    Hope this helps. Let us know if you have more follow up questions.

    Regards

    Mukul