topic Re: reboot fails from kernel in P1022 based target in P-Series

reboot fails from kernel in P1022 based target

rammurmu — Thu, 21 Sep 2017 04:07:58 GMT

Hi,

We have developed a custom board based on Freesccale development board P1022DS-PB REV F. The issue is 'reboot' command from kernel(after OS boot-up) doesn't work, though the 'reset' command in u-boot prompt does reboots the board successfully.

On probing the HRESET_REQ_B after issuing the 'reboot' command from kernel, it is found that HRESET_REQ_B is being triggered again after 600 micro seconds of de-assertion of HRESET. Subsequently , the above observation is repeated again and again in a loop ( Triggering of HRESET_REQ_B and de-ssertion of HRESET) and it is stuck in this state.

This test case is repeated on P1022DS-PB REV F development board and the observation is as expected(HRESET_REQ_B is not triggered again after de-assertion of HRESET) and it successfully reboots the target.

Any suggestions on further debugging would be appreciated.

Regards

Ram

Re: reboot fails from kernel in P1022 based target

Pavel — Wed, 27 Sep 2017 06:48:17 GMT

Look at the Table 4-2 of the P1022 Reference Manual about source for the HRESET_REQ_B assertion:

a watchdog timer, a boot sequencer failure (see Boot sequencer mode), or an eLBC ECC error.

Check the P1022 configuration pins on your board and boot sequencer on your board.

Have a great day,
Pavel Chubakov

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Re: reboot fails from kernel in P1022 based target

rammurmu — Wed, 27 Sep 2017 07:07:32 GMT

Hi Pavel,

Thanks for the update, however the issue is resolved to the point that meets our requirement. The root cause is still under debugging.

Basically the target we have has two non-volatile storage device. 1. Serial Flash (SPI) for boot code (u-boot) 2. Parallel NAND flash for uImage, File system, dtb and user data.

On target power-up , reset command does work perfectly fine from u-boot prompt. It is only after kernel boot-up that reboot command was not working(failed to reboot the target).

On debugging it is found that after probing and subsequent partitioning of Serial Flash(SPI) during kernel boot-up , the reboot does not work. i.e. trigger of HRESET_REQ does not reboot the target. However , on removing the Serial Flash probing and partitioning entry in dts, the reboot command does work from the kernel prompt. Since we do not require the Serial Flash(SPI) other than just the boot code (u-boot), we can meet our requirement by using the NAND flash only.