Re: Re: reboot is slow

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On 01/06/2012 08:52 AM, Elad Yosef wrote:
In vectors.S you have call to hal_cache_init()
which in turn calls hal_c_cache_init
The last one calls to dcache init and icache init and only after it
enables the caches by setting KO in config register.
Check that your clear Taglo/Taghi and tagd1/tagd2 (mtc0 %zero %28/29
2) before the invalidate loop, check your MIPS SUM doc to find the
exact registers you have.
What is the the address mapping? can it be that you are running from KSEG1?


indeed i am running from KSEG1 (i am running from flash at 0xBE000000) but running from ram is nut much faster.. i checked the code it is setting the registers correctly for the KSEG0 which is in ram... beside, i just had a look on the stock redboot startup script, and it starts by disabling the cache (cache off) then decompressing and still way faster. this is how hal_c_cache_init looks:

void hal_c_cache_init(unsigned long config1_val)
  volatile unsigned val;

  if (hal_init_icache(config1_val) == -1)
        /* Error */

  if (hal_init_dcache(config1_val) == -1)
        /* Error */

  // enable cached KSEG0
  asm volatile("mfc0 %0,$16;" : "=r"(val));
  val &= ~3;
  asm volatile("mtc0 %0,$16;" : : "r"(val));

it is only setting the cache for KSEG0  and not touching any thing else
On Fri, Jan 6, 2012 at 12:20 AM, Grant Edwards
<grant.b.edwards@xxxxxxxxx>  wrote:
On 2012-01-05, linux.chips<linux.chips@xxxxxxxxx>  wrote:

the caches are enabled (typing cache in the prompt tells me it on).
If the HAL code is broken somehow, it might not be telling the truth.

i am not sure where to find the memory initialization, currently
looking for it. the cpu clock is tunable as far as i know, i can see
options for cpu clock selections in the cdl files. how can i verify
the initialization and cpu clock are correct?
On all the parts I've ever used, there has been a way to configure the
hardware to output a clock signal on one of the peripheral pins (if
not the CPU clock then at least something with a known ratio to the
CPU clock).  I enable that feature, then use a 'scope to verify the
clock frequency.

Grant Edwards               grant.b.edwards        Yow! LOOK!!  Sullen
                                  at               American teens wearing
                                MADRAS shorts and "Flock of
                                                   Seagulls" HAIRCUTS!

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did not have much time to search for the memory initialization and cpu tuning code, any clues of where to search :)

thanks again

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