[SPAM] rk3399 TPL memory setup code triggers clock frequency limit assertion

[Jagan Teki]

On Mon, Aug 8, 2022 at 9:46 PM Michal Suchánek <msuchanek at suse.de> wrote:
>
> On Mon, Aug 08, 2022 at 04:28:33PM +0200, Xavier Drudis Ferran wrote:
> > El Sun, Aug 07, 2022 at 04:44:04PM +0200, Michal Suchánek deia:
> > > Hello,
> > >
> > > when compiled with clock debug rk3399 cannot be booted because memory
> > > setup code triggers clock assertion:
> > >
> > > U-Boot TPL 2022.07-00038-g61e11a8e9f-dirty (Aug 07 2022 - 16:13:17)
> > > TPL PLL at ff760000: fbdiv=50, refdiv=1, postdiv1=2, postdiv2=1, vco=1200000 khz, output=600000 khz
> > > TPL PLL at ff760020: fbdiv=50, refdiv=1, postdiv1=2, postdiv2=1, vco=1200000 khz, output=600000 khz
> > > TPL PLL at ff760080: fbdiv=99, refdiv=2, postdiv1=2, postdiv2=1, vco=1188000 khz, output=594000 khz
> > > TPL PLL at ff760060: fbdiv=64, refdiv=1, postdiv1=2, postdiv2=2, vco=1536000 khz, output=384000 khz
> > > TPL PLL at ff760040: fbdiv=12, refdiv=1, postdiv1=3, postdiv2=2, vco=288000 khz, output=48000 khz
> > > drivers/clk/rockchip/clk_rk3399.c:347: rkclk_set_pll: Assertion `vco_khz >= VCO_MIN_KHZ && vco_khz <= VCO_MAX_KHZ && output_khz >= OUTPUT_MIN_KHZ && output_khz <= OUTPUT_MAX_KHZ && div->fbdiv >= PLL_DIV_MIN && div->fbdiv <= PLL_DIV_MAX' failed.Channel 0: LPDDR4, 50MHz
> >
> > Sorry, I don't have time now. But It might be related to
> >
> > https://patchwork.ozlabs.org/project/uboot/patch/20220716103144.GA2167@begut/
> >
> > Apparently this clock is wrong but nobody finds any consequence of it being wrong.
> > If one asks for a 50MHz clock and gets a 48MHz clockthings might work anyway, but
> > it's nice that at least when one asks to be told of problems one is told.
>
> Yes, that's exactly what I was looking for. It resolves the discrepancy
> between the asssert and the set clock by adjusting the clock settings.

If I remember correctly when I work with YouMin on LPDDR4 the initial
code to start to check with was 50MHz (It was not working at that time
with 48MHz). Not sure what to make other changes to fix that to try on
48MHz.

Better resend the patch again and add YouMin and others to see for comments.

Jagan.