2010-06-29 11:57:36     JTAG console is slow and doesn't really work (gnICE+, BF525)

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2010-06-29 11:57:36     JTAG console is slow and doesn't really work (gnICE+, BF525)

Robert Homann (GERMANY)

Message: 90735   

 

Hi!

 

I have a BF525-based board here which I'm trying to install U-Boot on (on NAND). Both UARTs are in use on that device, so I'm trying to use the JTAG console via gnICE+ for interaction. The config file defines CONFIG_UART_CONSOLE_IS_JTAG and CONFIG_SYS_CONSOLE_IS_IN_ENV, and it sets stdin, stdout, and stderr to jtag.

 

Starting U-Boot sort of works, I can see output being displayed by the jtagconsole script. Only, it takes ~15 seconds before the U-Boot prompt is displayed after starting it. This seems very slow to me, therefore I think I'm doing something wrong -- or is this the to-be-expected speed?

 

What's worse, hitting any key on the U-Boot prompt results in lots of '\a' characters (bell, 0x07) being sent to the jtagconsole, and I cannot enter anything. So my U-Boot is not only slow, but also unusable over the JTAG console.

 

This is what I've tried:

 

 

$ bfin-gdbproxy bfin

 

$ bfin-elf-gdb

(gdb) set remotetimeout 300

(gdb) target remote localhost:2000

(gdb) load init.elf

(gdb) continue

(gdb) file u-boot

(gdb) load u-boot

(gdb) call memset(&_bss_vma, 0, &_bss_len)

(gdb) continue

 

 

 

I've also tried specifying JTAG frequencies of 30000000 and 6000000 using the --frequency option of bfin-gdbproxy, but to no avail.

 

Here is what I see in jtagconsole:

 

 

$ tools/jtagconsole

NOTE: the interrupt signal (normally ^C) has been remapped to ^T

 

 

U-Boot 2010.03-dirty-svn2336 (ADI-2010R1-pre) (Jun 29 2010 - 15:56:55)

 

CPU:   ADSP bf525-0.2 (Detected Rev: 0.2) (nand flash boot)

Clock: VCO: 398.131 MHz, Core: 398.131 MHz, System: 132.710 MHz

RAM:   64 MB

NAND:  256 MiB

Using default environment

 

In:    jtag

Out:   jtag

Err:   jtag

KGDB:  [on serial] ready

Hit any key to stop autoboot:  0

bfin>

 

 

 

U-Boot is u-boot-2010.03 from SVN, ported to our board. The GNU toolchain is the latest SVN version.

 

I see the same problems on a different BF523-based board when attempting to use the JTAG console. When using a free UART on that board for the console, however, everything is working correctly, so I suppose it must be a problem with the JTAG console configuration, or with its implementation.

 

Can someone give me a hint on why my JTAG console refuses to work properly?

 

As a fall-back, is it possible to activate a console over the 525's USB connection?

 

 

Robert Homann

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2010-06-29 13:28:03     Re: JTAG console is slow and doesn't really work (gnICE+, BF525)

Robin Getz (UNITED STATES)

Message: 90736   

 

Robert:

 

JTAG console is expected to be slower than a UART.

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2010-06-30 02:54:53     Re: JTAG console is slow and doesn't really work (gnICE+, BF525)

Robert Homann (GERMANY)

Message: 90744   

 

Ah, pity.

 

 

 

I think I could live with slow speed for now, but I still have no luck entering anything into the console. All I get is lots of bell characters after the first key press. Setting CONFIG_JTAG_CONSOLE_TIMEOUT to a larger value seems to have no effect whatsoever, which is the only tunable parameter I've found.

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2010-07-23 11:40:12     Re: JTAG console is slow and doesn't really work (gnICE+, BF525)

Mike Frysinger (UNITED STATES)

Message: 91664   

 

ive made things more robust in trunk and also added some speed optimizations.  if you wanted to retest, that'd be great.  you'll need both updated gdbproxy (toolchain) and u-boot.

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2010-07-23 12:41:28     Re: JTAG console is slow and doesn't really work (gnICE+, BF525)

Robert Homann (GERMANY)

Message: 91665   

 

Thanks, I'll try and report back next week.

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2010-07-26 05:07:37     Re: JTAG console is slow and doesn't really work (gnICE+, BF525)

Robert Homann (GERMANY)

Message: 91723   

 

I've tested the JTAG console from latest U-Boot, and I can confirm that it is working now, plus it is faster than before.

 

Thanks a lot, this is really useful!

 

 

Nex t thing to try for me is debugging applications in Linux over JTAG console, somehow.

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