2010-07-27 04:24:08     uboot on custom board not booting [fails in start.S]

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2010-07-27 04:24:08     uboot on custom board not booting [fails in start.S]

Mark Urup (DENMARK)

Message: 91765   

 

I've downloaded and compiled the newest uboot for a bf522 on our new board, and are loading it via visual dsp, but it does not boot (u-boot-2008.10-2009R1.1-rc1)

 

 

I've based my uboot on the bf526ezbrd config, and changed the memory timings and cpu type (to bf522-0.0).

 

I've tried to step through the uboot boot process in visual dsp, compared it with the uboot boot process on the bf526 ezbrd, and found out where it hangs.

 

It fails in the RTI call which is on line 200 of the start.S file in cpu/blackfin/start.S

 

What does the rti call do, and what could be wrong if uboot hangs there?

 

As far as I can see in the code, it has something to do with interrupts (as the comments also suggests).

But I don't really understand what happens in that piece of code (interrupts in assembler).

 

Regards Mark

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2010-07-27 04:32:24     Re: uboot on custom board not booting [fails in start.S]

Mike Frysinger (UNITED STATES)

Message: 91766   

 

how exactly are you "loading it via vdsp" ?  are you burning it into flash and letting the bootrom boot it, or are you loading it into external memory and executing it directly ?

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2010-07-27 05:08:54     Re: uboot on custom board not booting [fails in start.S]

Mark Urup (DENMARK)

Message: 91767   

 

Loading it into external memory, setting the PC counter to the "_start" address, and then running it.

 

I've also set the bootmode to BFIN_BOOT_BYPASS in uboot.

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2010-07-27 05:18:28     Re: uboot on custom board not booting [fails in start.S]

Mike Frysinger (UNITED STATES)

Message: 91768   

 

doing that isnt supported with vdsp.  the environment could easily be screwing things up.

 

bypass is not available on bf52x parts.

 

build with proper boot mode (like parallel ldr booting), burn u-boot into flash with vdsp, and then stop using vdsp.  if the system still isnt booting, there are methods for debugging:

https://docs.blackfin.uclinux.org/doku.php?id=bootloaders:u-boot:debugging

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2010-07-27 09:19:30     Re: uboot on custom board not booting [fails in start.S]

Mark Urup (DENMARK)

Message: 91773   

 

Are there any good tutorials for writing a "flash programmer" driver, or any good places to start with this?

 

I see there is one for the BF526 EZBRD, but that does not work for the bf522, even though the spi flash are the same.

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2010-07-27 09:28:31     Re: uboot on custom board not booting [fails in start.S]

Robin Getz (UNITED STATES)

Message: 91774   

 

Mark:

 

Which environment are you asking for? Flash driver for U-Boot?

 

-Robin

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2010-07-27 09:45:28     Re: uboot on custom board not booting [fails in start.S]

Mark Urup (DENMARK)

Message: 91775   

 

Well, a flash driver for visual dsp, for loading the initial u-boot.

 

I have a clean board, that has never been booted before, so I need some way of loading uboot for the first time.

 

If what Mike said is correct, I would need eiher a flash driver for visual dsp, or to load uboot via uart to being with, but since this is a new board I figured it would be good to do i via jtag, so I also can monitor the registers, should anything go wrong...

 

/Mark

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2010-07-27 13:45:24     Re: uboot on custom board not booting [fails in start.S]

Robin Getz (UNITED STATES)

Message: 91777   

 

Mark:

 

Either:

 

- use UART boot (highly suggested - this is the easiest path).

 

- use the gnICE (using gdbproxy)

 

- use the USB-100B (using gdbproxy, you will need to build trunk toolchain)

 

- use VDSP (but we can't help out with this - we don't use/know/support VDSP - try on ez.analog.com)

 

-Robin

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2010-07-27 14:05:39     Re: uboot on custom board not booting [fails in start.S]

Mike Frysinger (UNITED STATES)

Message: 91779   

 

why doesnt it work for the bf522 ?  unless you've hooked it up to a different spi bus or spi cs from the bf526-ezbrd ?  otherwise, everything should be the same.

 

the flash programmers do have dedicated projects, so it should be easy for you to open that in vdsp, change the settings to target the bf522, and tweak the source to use the right spi bus and spi cs for your specific platform.

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2010-07-29 04:12:04     Re: uboot on custom board not booting [fails in start.S] - [SOLVED]

Mark Urup (DENMARK)

Message: 91866   

 

Ok, so I got it working using uart boot - thanks.

It was as easy as you said - we've just usually used vdsp, and done the memory load from there.

But this is much better since I can do it all from linux now :-)

 

The SPI flashing problem is a hw issue. I think we're missing some pull-up's or down's.

 

Anyway, I now have uboot up and responding on the uart, and loading uboot this way is much easier (except I have to move some darn small resistors to change the boot mode).

 

Thansk for all the help, yet again.

 

Regards

Mark

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