Re: [PATCH v6 3/6] clk: spacemit: Add clock support for SpacemiT K1 SoC
From: Yixun Lan
Date: Wed Apr 09 2025 - 20:40:40 EST
On 14:37 Tue 08 Apr , Alex Elder wrote:
> On 4/1/25 12:24 PM, Haylen Chu wrote:
> > The clock tree of K1 SoC contains three main types of clock hardware
> > (PLL/DDN/MIX) and has control registers split into several multifunction
> > devices: APBS (PLLs), MPMU, APBC and APMU.
> >
> > All register operations are done through regmap to ensure atomiciy
> > between concurrent operations of clock driver and reset,
> > power-domain driver that will be introduced in the future.
> >
> > Signed-off-by: Haylen Chu <heylenay@xxxxxxx>
>
> I have a few more comments here but I think this is getting very
> close to ready. You addressed pretty much everything I mentioned.
>
> > ---
> > drivers/clk/Kconfig | 1 +
> > drivers/clk/Makefile | 1 +
> > drivers/clk/spacemit/Kconfig | 18 +
> > drivers/clk/spacemit/Makefile | 5 +
> > drivers/clk/spacemit/apbc_clks | 100 +++
> > drivers/clk/spacemit/ccu-k1.c | 1316 +++++++++++++++++++++++++++++
> > drivers/clk/spacemit/ccu_common.h | 48 ++
> > drivers/clk/spacemit/ccu_ddn.c | 83 ++
> > drivers/clk/spacemit/ccu_ddn.h | 47 ++
> > drivers/clk/spacemit/ccu_mix.c | 268 ++++++
> > drivers/clk/spacemit/ccu_mix.h | 218 +++++
> > drivers/clk/spacemit/ccu_pll.c | 157 ++++
> > drivers/clk/spacemit/ccu_pll.h | 86 ++
> > 13 files changed, 2348 insertions(+)
> > create mode 100644 drivers/clk/spacemit/Kconfig
> > create mode 100644 drivers/clk/spacemit/Makefile
> > create mode 100644 drivers/clk/spacemit/apbc_clks
> > create mode 100644 drivers/clk/spacemit/ccu-k1.c
> > create mode 100644 drivers/clk/spacemit/ccu_common.h
> > create mode 100644 drivers/clk/spacemit/ccu_ddn.c
> > create mode 100644 drivers/clk/spacemit/ccu_ddn.h
> > create mode 100644 drivers/clk/spacemit/ccu_mix.c
> > create mode 100644 drivers/clk/spacemit/ccu_mix.h
> > create mode 100644 drivers/clk/spacemit/ccu_pll.c
> > create mode 100644 drivers/clk/spacemit/ccu_pll.h
> >
> > diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
> > index 713573b6c86c..19c1ed280fd7 100644
> > --- a/drivers/clk/Kconfig
> > +++ b/drivers/clk/Kconfig
> > @@ -517,6 +517,7 @@ source "drivers/clk/samsung/Kconfig"
> > source "drivers/clk/sifive/Kconfig"
> > source "drivers/clk/socfpga/Kconfig"
> > source "drivers/clk/sophgo/Kconfig"
> > +source "drivers/clk/spacemit/Kconfig"
> > source "drivers/clk/sprd/Kconfig"
> > source "drivers/clk/starfive/Kconfig"
> > source "drivers/clk/sunxi/Kconfig"
> > diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
> > index bf4bd45adc3a..42867cd37c33 100644
> > --- a/drivers/clk/Makefile
> > +++ b/drivers/clk/Makefile
> > @@ -145,6 +145,7 @@ obj-$(CONFIG_COMMON_CLK_SAMSUNG) += samsung/
> > obj-$(CONFIG_CLK_SIFIVE) += sifive/
> > obj-y += socfpga/
> > obj-y += sophgo/
> > +obj-y += spacemit/
> > obj-$(CONFIG_PLAT_SPEAR) += spear/
> > obj-y += sprd/
> > obj-$(CONFIG_ARCH_STI) += st/
> > diff --git a/drivers/clk/spacemit/Kconfig b/drivers/clk/spacemit/Kconfig
> > new file mode 100644
> > index 000000000000..4c4df845b3cb
> > --- /dev/null
> > +++ b/drivers/clk/spacemit/Kconfig
> > @@ -0,0 +1,18 @@
> > +# SPDX-License-Identifier: GPL-2.0-only
> > +
> > +config SPACEMIT_CCU
> > + tristate "Clock support for SpacemiT SoCs"
>
> I don't know the answer to this, but... Should this be a Boolean
> rather than tristate? Can a SpacemiT K1 SoC function without the
> clock driver built in to the kernel?
>
I agree to make it a Boolean, we've already made pinctrl driver Boolean
and pinctrl depend on clk, besides, the SoC is unlikely functional
without clock built in as it's such critical..
> > + depends on ARCH_SPACEMIT || COMPILE_TEST
> > + select MFD_SYSCON
> > + help
> > + Say Y to enable clock controller unit support for SpacemiT SoCs.
> > +
> > +if SPACEMIT_CCU
> > +
> > +config SPACEMIT_K1_CCU
> > + tristate "Support for SpacemiT K1 SoC"
>
> If you decide SPACEMIT_CCU needs to be Boolean, this one should
> be Boolean too.
>
[...]
> > + CCU_PLL_RATE(1600000000UL, 0x0050cd61, 0x43eaaaab),
> > + CCU_PLL_RATE(1800000000UL, 0x0050cd61, 0x4b000000),
> > + CCU_PLL_RATE(2000000000UL, 0x0050dd62, 0x2aeaaaab),
> > + CCU_PLL_RATE(2457600000UL, 0x0050dd64, 0x330ccccd),
> > + CCU_PLL_RATE(3000000000UL, 0x0050dd66, 0x3fe00000),
> > + CCU_PLL_RATE(3200000000UL, 0x0050dd67, 0x43eaaaab),
> > +};
> > +
> > +CCU_PLL_DEFINE(pll1, pll1_rate_tbl, APBS_PLL1_SWCR1, APBS_PLL1_SWCR3, MPMU_POSR,
> > + POSR_PLL1_LOCK, CLK_SET_RATE_GATE);
> > +CCU_PLL_DEFINE(pll2, pll2_rate_tbl, APBS_PLL2_SWCR1, APBS_PLL2_SWCR3, MPMU_POSR,
> > + POSR_PLL2_LOCK, CLK_SET_RATE_GATE);
> > +CCU_PLL_DEFINE(pll3, pll3_rate_tbl, APBS_PLL3_SWCR1, APBS_PLL3_SWCR3, MPMU_POSR,
> > + POSR_PLL3_LOCK, CLK_SET_RATE_GATE);
> > +
>
> I suspect Yixun would like you to have lines like the next one be
> 84 characters wide--slighly wider than the 80 column limit.
>
> I'm not going to ask you to change it (but he might).
>
Yes, I do prefer 100 cloumn.. please check more of this files
But anyway, I can bear with it if clk subsystem maintainer have enforced
80 column policy for the whole clk subsystem, to make consistent
--
Yixun Lan (dlan)
Gentoo Linux Developer
GPG Key ID AABEFD55