nxp-mcuxpresso/mcux-sdk

[BUG] MIMXRT1176 CLOCK_GetRootClockFreq returns wrong frequency when post divider is 1

Closed this issue · 2 comments

ChristianMosbach commented

Describe the bug
CLOCK_GetRootClockFreq returns wrong frequency when post divider is set to divide by 1 (0b11)

To Reproduce

  • Environment (please complete the following information):
    • Tag/Commit hash: [MCUX_2.11.0]
    • Toolchain: [ARMGCC 10.3-2021.07]
    • Board/SoC: [MIMXRT1176 on MIMXrt1170-EVK]
    • Example [iled_blinky_cm7]
  • Steps to reproduce the behavior:
    1. In MCUXpresso use the excample MIMXRT1176 iled_blinky_cm7
    2. Configure CortexM7 core root clock to ARM_PLL_CLK and the Divider to 3
    3. Configure ArmPLL to 1875 and the Post Divider to 1
    4. Update Code
    5. Set a breakpoint board/clock_config.c on the line with "SystemCoreClock = CLOCK_GetRootClockFreq(kCLOCK_Root_M7);"
    6. Read out SystemCoreClock. On My system says its 37500000.

Expected behavior
SystemCoreClock should be 600000000

Screenshots and console output
image

Additional context
CLOCK_GetPllFreq(kCLOCK_PllArm) does not calculate the post divider correctly. if post divider is 1, the register holds 0x3. fsl_clock.c line 1442 shifts postDiv to 0x10, But the divider for the calculation should be 1.

mcuxsusan commented

Thanks for reporting the issue, the bug fix will be available soon.

mcuxsusan commented

Hi @ChristianMosbach, please check the fix in latest main 1389627