P4080DS kernel debugging feature

[avasu]

Hello,

I am currently working on the P4080DS platform. In Kernel menuconfig, I enabled "Kernel debugging" and "Debug VM" features and compiled the kernel.

During kernel booting, the kernel hangs with a message "drivers/rtc/hctosys.c: unable to open rtc device (rtc0)"

RTC clock is also enabled in the kernel.

This is the kernel version that I use.

Linux p4080ds-p1 3.0.34-rt55-02404-gla39570 #1 SMP PREEMPT PATCH RT ppx GNU/Linux

Could anyone help me on this?  I can share more information if required.

Thanks,

Vasu

[lunminliang]

Please find below technical support comment:

When kernel boots it copies to RTC time into the system time(software clock which is calculated by the Linux kernel as the number of seconds since epoch or unix time start date)by executing a small program referred to as hctosys.c. The hctosys.c reads the hctosys_device, rtc0  and therefore you need to build the DS1307 driver into the kernel for this operation to be possible on startup . This is similarly done by configuring the config file follows:

CONFIG_RTC_CLASS=y

CONFIG_RTC_DRV_DS1307=y

Enable DTS and rebuild the kernel again.  Let me know if you still see the error message.