Re: LS1021A performance

[Lucas Stach <l.stach@pengutronix.de>]

Hi Renaud,

Am Donnerstag, dem 30.03.2023 um 13:31 +0000 schrieb Renaud Barbier:
> 
>  
> > Can you compare SHA256 instead and see if the difference is still as stark?
> > Make sure that CONFIG_DIGEST_SHA256_ARM is enabled.
> The SHA256 is enabled. SHA256 on a 1 MB file:
> Barebox: 843ms
> Linux: 
> [root@openware]# time sha256sum /tmp/mtd0
> eef67a3327e3eaa50ee7b1dad87901465f00d76a6308e360a2fedab82c79f493  /tmp/mtd0
> 
> real    0m0.059s
> user    0m0.056s
> sys     0m0.001s
> 
> On another note, the boot loader using the LS1021A is much slower than using the PPC P1014.
> I compare those two as we used the LS1021A as a replacement for P1014 on a board (same peripherals, same boot sequence)
> The P1014 reach the prompt in 200ms while the LS1021 takes 700ms.
> 
> Also, I noticed that the pageflags is different for the DDR memory on Barebox and Linux as seen by the Lauterbach:
> Barebox: write-back/no allocate
> Linux : Inner:write-back/allocate outer: write-back/allocate
> Could that mean the L2 cache Is not used?
> > 
> > Do barebox and Linux run at the same CPU frequency?
> According to the Lauterbach, clock ratio have not changed in the clocking registers
> > 

As the LS1021A is based on a Cortex A7 your board lowlevel init needs
to call cortex_a7_lowlevel_init() for the caches to work properly.

It's probably a good idea to add a ls1021 lowlevel init function which
calls both of those functions together, like
imx6ul_cpu_lowlevel_init().

Regards,
Lucas

> > Cheers,
> > Ahmad
> > 
> > > 
> > > Cheers,
> > > Renaud
> > > 
> > > 
> > > 
> > > 
> > 
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