RKI Image for Raspberry PI 2

Pavel Pisa ppisa4lists at pikron.com
Thu May 26 07:10:20 UTC 2016


Hello Alan,

thanks for the report.

On Thursday 26 of May 2016 04:03:21 Alan Cudmore wrote:
> I just tried the firmware in the repository above ( did not realize the
> whole git repo was over 3 gigs! )
>
> I backed up my RTEMS pi SD card and copied the contents of the firmware
> "boot" directory to my card. I replaced kernel.img and kernel7.img with my
> RKI images for the Pi and Pi2.
>
> RTEMS boots on my Pi Model A+, but not on the 2. Same RTEMS images that
> booted on my old card.
>
> My old card boot directory is based off of a NOOBS installation.  I'll have
> to investigate more.. Maybe I can upload my SD card contents to my github
> account ( I think that would be OK with the license, since the official
> firmware is on github as well )

Please, can you check new and old firmware with my branch
rtems-rpi-devel from

  https://github.com/ppisa/rtems

to check if it works at leas on the firmware known to work with
your previous build?

As for the debugging, I have JTAG working on RPi1.
I have no real HW experience with RTEMS on RPi2.
(I have prepared RT Linux kernel for my colleagues
at university who has it, but I do not consider to buy RPi2,
but I consider RPi3).

To find where boot stucks, add next lines
------------------------------------------------------------------------
#include <bsp/usart.h>

void ll_chrout(char ch)
{
  bcm2835_usart_fns.deviceWritePolled(0, ch);
}

void ll_strout(char *str)
{
  char ch;
  while ((ch = *(str++)) != 0) {
    if (ch == '\n')
      bcm2835_usart_fns.deviceWritePolled(0, '\r');
    bcm2835_usart_fns.deviceWritePolled(0, ch);
  }
}
------------------------------------------------------------------------

to c/src/lib/libbsp/arm/raspberrypi/startup/bspstarthooks.c

then add/spread some

ll_strout(" XXX reached\n");

over the RTEMS sources, start with the functions

void BSP_START_TEXT_SECTION bsp_start_hook_0(void)

void BSP_START_TEXT_SECTION bsp_start_hook_1(void)


In c/src/lib/libbsp/arm/shared/include/arm-cp15-start.h
is critical

    arm_cp15_set_domain_access_control(dac);

can be replaced for test by

    arm_cp15_set_domain_access_control(-1);

add print in start and end of arm_cp15_start_setup_translation_table()

In cpukit/score/src/threadhandler.c critical is

    level = executing->Start.isr_level;
   _ISR_Set_level( level );

where IRQ can fire and if exeption table is misconfigured then deadly
fails.

Best wishes,

             Pavel

  




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