No prints from kernel running on DRA608(AM335x) board

Hi Gangadhar,

If your board is using dts concept then machine ID concept will not come to picture.

Hi Titusrathinaraj Stalin,

                                           Thanks for this info. Please tell me what are the other reasons for which kernel hangs(no prints). Right now I'm testing my DDR.

Regards,

Gangadhar

Hi Gangadhar,

You can use our TI E2E forum to search your linux booting issues.

http://e2e.ti.com/support/embedded/linux/f/354/t/347095.aspx

http://e2e.ti.com/support/embedded/linux/f/354/t/347096.aspx

Could you please share your bootargs.

What is your DDR memory size ?

Are you using custom board ?

What is your reference design  and SDK details ?

What are the hw changes have you made than reference board ?

Hi Titusrathinaraj Stalin,

Thanks.

1. Bootargs: console=ttyO0,115200n8 ramroot=/dev/ram0 rw ramdisk_size=65536 initrd=${rdaddr},64M ramrootfstype=ext2

2. DDR: 256MB

3. Custom board with DRA608(automotive grade of AM335x) processor

4. SDK sitara 7.0, I'm building the kernel same as that for AM335x

5. there are lots of HW differences b/w ref. and custom boards. I'm using simple dts file with uart and nor currently.

The same images - kernel and dtb run on AM335x evm but not on custom board.

I've attached my dts.6811.j5.dts.txt

I'm doing ramboot.

Regards,

Gangadhar

Hi,

I'm not familiar with this processor and dts stuffs.

    chosen {
        bootargs = "console=ttyS0 root=/dev/ram";
        linux,stdout-path = &uart0;
    };

1) Use "/dev/ttyO0" instead /dev/ttyS0

2) Try to pass "mem=30M" variable in u-boot bootargs.

Hi,

    I tried whatever you suggested. No change, same issue.

Regards,

Gangadhar

Gangadhar,

The DRA608 is the same as the commercial AM3356 device. The DRA608 is just the automotive grade p/n.

The custom board you're using uses UART3 for console output instead of UART0. The u-boot-spl & u-boot which Chandra already customized should already have UART3 initialized. I think all you have to do is to redirect from UART0 to UART3 in kernel.

Regards,

Mark

Hi Mark,

              On custom board, we've done work around(HW) and got prints on UART0 for uboot. Kernel should also give prints on UART0.

Regards,

Gangadhar

Gangadhar,

Ok, I see. The one modified board that Chandra has does use UART0. All other custom boards use UART3. I wasn't sure which board you were using. In this case, since your board uses UART0, I'm not sure why the kernel wouldn't be able to print to console.

Regards,

Mark

Hi Gangadhar,

A similar query is getting attended by Miroslav in Sitara Forum at http://e2e.ti.com/support/arm/sitara_arm/f/791/t/350101.aspx

If it is the same, it is better to have solutions at one single thread instead of informations getting scattered at two different threads.

Regards,

Shankari

Hi All,

1. If I use SDK6.0 generate uImage, run as bootm uImage on my custom board, kernel boots and I get prints.

2. If I use SDK7.0 generate uImage/zImage and run as bootm uImage - dtb or bootz zImage - dtb on my custom board , kernel does not boot and no prints. But the same images  perfectly work on AM335x EVM.

What am I missing? To generate kernel I just  used make tisdk_am335x-evm_defconfig and make / make uImage.

In my previous posts I've also attached the dts file that I'm using.

Regards,

Gangadhar

Hi All,

With SDK 7.0, linux - 3.12, custom board, I used early_print() to get prints. No prints from printk(), Also kernel hangs

after calling do_initcall_level() twice. Sequence: start_kernel -> rest_init() -> kernel_init() -> kernel_init_freeable() -> do_basic_setup() -> do_initcalls  -> do_initcall_level()

The same image gives prints(printk()) on EVM.

1. I checked bootargs using early_print(), it's correct:  console=ttyO0,115200n8 root=/dev/ram0 rw ramdisk_size=65536 initrd=0x81000000,64M rootfstype=ext2

2. I checked my uart0 pin mux in dts file, it matches that in uboot.

3. I also tried removing uart0 pin mux in dts as it'll be initiallized in uboot, but the issue remains the same.

What am I missing?

Regards,

Gangadhar

Hi,

Sounds good.

Thanks for your update.