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AM4378: RTOS PDK: Change the OPP frequency

Part Number: AM4378

Hi TI,

I am now using AM4378 based TI-RTOS PDK to do the diagnostic test using bare-metal code by loading the program through CCS. I want to perform the test in 1GHz (OPP_Nitro) mode, how to check whether this frequency mode is enabled?

If not, how to enable 1GHz (OPP_Nitro) for loading program through JTAG? Please provide the steps/change to perform the test in nitro (1 GHz) mode?

Regards,

Monish P

  • Hello Monish P,

    I want to perform the test in 1GHz (OPP_Nitro) mode, how to check whether this frequency mode is enabled?

    You'll first need to read CTRL_STS register to determine the crystal clock frequency. Please refer to the AM437x TRM:

    • Table 7-15. CTRL_STS Register Field Descriptions of: SYSBOOT15_14 (clkin)

    Then you'll need to read the PLL registers to get the divider (N), multiplier (M), and post divider factor (M2):

    • Table 6-307. PRCM_CM_CLKSEL_DPLL_MPU Register Field Descriptions: DPLL_MULT (M), DPLL_DIV (N)
    • Table 6-308. PRCM_CM_DIV_M2_DPLL_MPU Register Field Descriptions: DPLL_CLKOUT_DIV (M2) 

    Then you can determine the MPU frequency by clikin/(N+1)*M/M2.

    If not, how to enable 1GHz (OPP_Nitro) for loading program through JTAG?

    You can configure the MPU frequency by the CCS GEL file. Please refer to <ccs_folder>\ccs\ccs_base\emulation\boards\idk_am437x\gel\idk_am437x.gel, function MPU_PLL_Config(). For example, if your crystal clock is 24MHz, you can configure MPU PLL as below to get 1GHz:

    MPU_PLL_Config(CLKIN, 2, 125, 1); // 24/(2+1)*125/1 => 1000MHz

    Regards,

    Jianzhong