Re: [PATCH v2] sunxi: clock: H6/H616: Fix PLL clock factor encodings

["Jernej Škrabec" <jernej.skrabec@gmail.com>]

Hi!

Dne četrtek, 27. maj 2021 ob 01:49:48 CEST je Andre Przywara napisal(a):
> On Wed,  5 May 2021 13:53:05 +0100
> Andre Przywara <andre.przywara@arm.com> wrote:
> 
> Hi,
> 
> > Most clock factors and dividers in the H6 PLLs use a "+1 encoding",
> > which we were missing on two occasions.
> 
> can someone please confirm that I didn't mess this up?
> 
> Cheers,
> Andre
> 
> > This fixes the MMC clock setup on the H6, which could be slightly off due
> > to the wrong parent frequency:
> > mmc 2 set mod-clk req 52000000 parent 1176000000 n 2 m 12 rate 49000000
> > 
> > Also the CPU frequency was a tad too high before.
> > 
> > Signed-off-by: Andre Przywara <andre.przywara@arm.com>
> > ---
> > Changelog v1 .. v2:
> > - Also fix PLL5 factor calculation (video, currently unused)
> > - Also fix PLL1 factor calculation (CPU clock)
> > 
> >  arch/arm/include/asm/arch-sunxi/clock_sun50i_h6.h | 4 ++--
> >  arch/arm/mach-sunxi/clock_sun50i_h6.c             | 2 +-
> >  2 files changed, 3 insertions(+), 3 deletions(-)
> > 
> > diff --git a/arch/arm/include/asm/arch-sunxi/clock_sun50i_h6.h
> > b/arch/arm/include/asm/arch-sunxi/clock_sun50i_h6.h index
> > 62abfc4ef6b..2e076cf594d 100644
> > --- a/arch/arm/include/asm/arch-sunxi/clock_sun50i_h6.h
> > +++ b/arch/arm/include/asm/arch-sunxi/clock_sun50i_h6.h
> > @@ -233,14 +233,14 @@ struct sunxi_ccm_reg {
> > 
> >  #define CCM_PLL1_OUT_EN			BIT(27)
> >  #define CCM_PLL1_CLOCK_TIME_2		(2 << 24)
> >  #define CCM_PLL1_CTRL_P(p)		((p) << 16)
> > 
> > -#define CCM_PLL1_CTRL_N(n)		((n) << 8)
> > +#define CCM_PLL1_CTRL_N(n)		(((n) - 1) << 8)
> > 
> >  /* pll5 bit field */
> >  #define CCM_PLL5_CTRL_EN		BIT(31)
> >  #define CCM_PLL5_LOCK_EN		BIT(29)
> >  #define CCM_PLL5_LOCK			BIT(28)
> >  #define CCM_PLL5_OUT_EN			BIT(27)
> > 
> > -#define CCM_PLL5_CTRL_N(n)		((n) << 8)
> > +#define CCM_PLL5_CTRL_N(n)		(((n) - 1) << 8)

H6 and H616 DRAM drivers actually consider this "- 1" in the code. Either drop 
this change or fix DRAM drivers.

With that:
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>

Best regards,
Jernej

> > 
> >  #define CCM_PLL5_CTRL_DIV1(div1)	((div1) << 0)
> >  #define CCM_PLL5_CTRL_DIV2(div0)	((div0) << 1)
> > 
> > diff --git a/arch/arm/mach-sunxi/clock_sun50i_h6.c
> > b/arch/arm/mach-sunxi/clock_sun50i_h6.c index 492fc4a3fca..a947463e0a5
> > 100644
> > --- a/arch/arm/mach-sunxi/clock_sun50i_h6.c
> > +++ b/arch/arm/mach-sunxi/clock_sun50i_h6.c
> > @@ -94,7 +94,7 @@ unsigned int clock_get_pll6(void)
> > 
> >  	int m = IS_ENABLED(CONFIG_MACH_SUN50I_H6) ? 4 : 2;
> >  	
> >  	uint32_t rval = readl(&ccm->pll6_cfg);
> > 
> > -	int n = ((rval & CCM_PLL6_CTRL_N_MASK) >> CCM_PLL6_CTRL_N_SHIFT);
> > +	int n = ((rval & CCM_PLL6_CTRL_N_MASK) >> CCM_PLL6_CTRL_N_SHIFT) + 
1;
> > 
> >  	int div1 = ((rval & CCM_PLL6_CTRL_DIV1_MASK) >>
> >  	
> >  			CCM_PLL6_CTRL_DIV1_SHIFT) + 1;
> >  	
> >  	int div2 = ((rval & CCM_PLL6_CTRL_DIV2_MASK) >>