[PATCH v13 01/17] clk: Add RISC-V Canaan Kendryte K210 clock driver

Damien Le Moal Damien.LeMoal at wdc.com
Sat Jan 23 01:22:45 EST 2021


On 2021/01/18 11:03, Damien Le Moal wrote:
> Add a clock provider driver for the Canaan Kendryte K210 RISC-V SoC.
> This new driver with the compatible string "canaan,k210-clk" implements
> support for the full clock structure of the K210 SoC. Since it is
> required for the correct operation of the SoC, this driver is
> selected by default for compilation when the SOC_CANAAN option is
> selected.
> 
> With this change, the k210-sysctl driver is turned into a simple
> platform driver which enables its power bus clock and triggers
> populating its child nodes. The sysctl driver retains the SOC early
> initialization code, but the implementation now relies on the new
> function k210_clk_early_init() provided by the new clk-k210 driver.
> 
> The clock structure implemented and many of the coding ideas for the
> driver come from the work by Sean Anderson on the K210 support for the
> U-Boot project.
> 
> Cc: Stephen Boyd <sboyd at kernel.org>
> Cc: Michael Turquette <mturquette at baylibre.com>
> Cc: linux-clk at vger.kernel.org
> Signed-off-by: Damien Le Moal <damien.lemoal at wdc.com>

Stephen,

Ping ? Could you review this version please ?

I addressed all your comments, except the addition of a timeout in the pll lock
wait loop. The reason is that if the hardware misbehave there, the CPU and/or
third SRAM bank are likely to not work either and the board will not even boot
(it will hang in the early soc init code). So I do not think adding a timeout is
useful.


> ---
>  MAINTAINERS                      |    1 +
>  drivers/clk/Kconfig              |    8 +
>  drivers/clk/Makefile             |    1 +
>  drivers/clk/clk-k210.c           | 1012 ++++++++++++++++++++++++++++++
>  drivers/soc/canaan/Kconfig       |   18 +-
>  drivers/soc/canaan/Makefile      |    2 +-
>  drivers/soc/canaan/k210-sysctl.c |  205 ++----
>  include/soc/canaan/k210-sysctl.h |    2 +
>  8 files changed, 1071 insertions(+), 178 deletions(-)
>  create mode 100644 drivers/clk/clk-k210.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index d56f32b0140b..d5559d325088 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -3870,6 +3870,7 @@ CANAAN/KENDRYTE K210 SOC SYSTEM CONTROLLER DRIVER
>  M:	Damien Le Moal <damien.lemoal at wdc.com>
>  L:	linux-riscv at lists.infradead.org
>  S:	Maintained
> +F:	Documentation/devicetree/bindings/mfd/canaan,k210-sysctl.yaml
>  F:	drivers/soc/canaan/
>  F:	include/soc/canaan/
>  
> diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
> index 85856cff506c..cb971f6632e2 100644
> --- a/drivers/clk/Kconfig
> +++ b/drivers/clk/Kconfig
> @@ -368,6 +368,14 @@ config COMMON_CLK_FIXED_MMIO
>  	help
>  	  Support for Memory Mapped IO Fixed clocks
>  
> +config COMMON_CLK_K210
> +	bool "Clock driver for the Canaan Kendryte K210 SoC"
> +	depends on COMMON_CLK && OF
> +	depends on RISCV && SOC_CANAAN
> +	default SOC_CANAAN
> +	help
> +	  Support for the Canaan Kendryte K210 RISC-V SoC clocks.
> +
>  source "drivers/clk/actions/Kconfig"
>  source "drivers/clk/analogbits/Kconfig"
>  source "drivers/clk/baikal-t1/Kconfig"
> diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
> index dbdc590e7de3..5f8f9f135df5 100644
> --- a/drivers/clk/Makefile
> +++ b/drivers/clk/Makefile
> @@ -37,6 +37,7 @@ obj-$(CONFIG_COMMON_CLK_ASPEED)		+= clk-aspeed.o
>  obj-$(CONFIG_MACH_ASPEED_G6)		+= clk-ast2600.o
>  obj-$(CONFIG_ARCH_HIGHBANK)		+= clk-highbank.o
>  obj-$(CONFIG_CLK_HSDK)			+= clk-hsdk-pll.o
> +obj-$(CONFIG_COMMON_CLK_K210)		+= clk-k210.o
>  obj-$(CONFIG_COMMON_CLK_LOCHNAGAR)	+= clk-lochnagar.o
>  obj-$(CONFIG_COMMON_CLK_MAX77686)	+= clk-max77686.o
>  obj-$(CONFIG_COMMON_CLK_MAX9485)	+= clk-max9485.o
> diff --git a/drivers/clk/clk-k210.c b/drivers/clk/clk-k210.c
> new file mode 100644
> index 000000000000..429db4904ad6
> --- /dev/null
> +++ b/drivers/clk/clk-k210.c
> @@ -0,0 +1,1012 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (C) 2019-20 Sean Anderson <seanga2 at gmail.com>
> + * Copyright (c) 2019 Western Digital Corporation or its affiliates.
> + */
> +#define pr_fmt(fmt)     "k210-clk: " fmt
> +
> +#include <linux/io.h>
> +#include <linux/slab.h>
> +#include <linux/spinlock.h>
> +#include <linux/platform_device.h>
> +#include <linux/of.h>
> +#include <linux/of_clk.h>
> +#include <linux/of_platform.h>
> +#include <linux/of_address.h>
> +#include <linux/clk-provider.h>
> +#include <linux/bitfield.h>
> +#include <linux/delay.h>
> +#include <asm/soc.h>
> +#include <soc/canaan/k210-sysctl.h>
> +
> +#include <dt-bindings/clock/k210-clk.h>
> +
> +/*
> + * Clocks parameters.
> + */
> +struct k210_sysclk;
> +
> +struct k210_clk {
> +	int id;
> +	struct k210_sysclk *ksc;
> +	struct clk_hw hw;
> +};
> +
> +struct k210_clk_cfg {
> +	const char *name;
> +	u8 gate_reg;
> +	u8 gate_bit;
> +	u8 div_reg;
> +	u8 div_shift;
> +	u8 div_width;
> +	u8 div_type;
> +	u8 mux_reg;
> +	u8 mux_bit;
> +};
> +
> +enum k210_clk_div_type {
> +	K210_DIV_NONE,
> +	K210_DIV_ONE_BASED,
> +	K210_DIV_DOUBLE_ONE_BASED,
> +	K210_DIV_POWER_OF_TWO,
> +};
> +
> +#define K210_GATE(_reg, _bit)	\
> +	.gate_reg = (_reg),	\
> +	.gate_bit = (_bit)
> +#define K210_DIV(_reg, _shift, _width, _type)	\
> +	.div_reg = (_reg),			\
> +	.div_shift = (_shift),			\
> +	.div_width = (_width),			\
> +	.div_type = (_type)
> +#define K210_MUX(_reg, _bit)	\
> +	.mux_reg = (_reg),	\
> +	.mux_bit = (_bit)
> +
> +static struct k210_clk_cfg k210_clk_cfgs[K210_NUM_CLKS] = {
> +
> +	/* Gated clocks, no mux, no divider */
> +	[K210_CLK_CPU] = {
> +		.name = "cpu",
> +		K210_GATE(K210_SYSCTL_EN_CENT, 0)
> +	},
> +	[K210_CLK_DMA] = {
> +		.name = "dma",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 1)
> +	},
> +	[K210_CLK_FFT] = {
> +		.name = "fft",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 4)
> +	},
> +	[K210_CLK_GPIO] = {
> +		.name = "gpio",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 5)
> +	},
> +	[K210_CLK_UART1] = {
> +		.name = "uart1",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 16)
> +	},
> +	[K210_CLK_UART2] = {
> +		.name = "uart2",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 17)
> +	},
> +	[K210_CLK_UART3] = {
> +		.name = "uart3",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 18)
> +	},
> +	[K210_CLK_FPIOA] = {
> +		.name = "fpioa",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 20)
> +	},
> +	[K210_CLK_SHA] = {
> +		.name = "sha",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 26)
> +	},
> +	[K210_CLK_AES] = {
> +		.name = "aes",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 19)
> +	},
> +	[K210_CLK_OTP] = {
> +		.name = "otp",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 27)
> +	},
> +	[K210_CLK_RTC] = {
> +		.name = "rtc",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 29)
> +	},
> +
> +	/* Gated divider clocks */
> +	[K210_CLK_SRAM0] = {
> +		.name = "sram0",
> +		K210_GATE(K210_SYSCTL_EN_CENT, 1),
> +		K210_DIV(K210_SYSCTL_THR0, 0, 4, K210_DIV_ONE_BASED)
> +	},
> +	[K210_CLK_SRAM1] = {
> +		.name = "sram1",
> +		K210_GATE(K210_SYSCTL_EN_CENT, 2),
> +		K210_DIV(K210_SYSCTL_THR0, 4, 4, K210_DIV_ONE_BASED)
> +	},
> +	[K210_CLK_ROM] = {
> +		.name = "rom",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 0),
> +		K210_DIV(K210_SYSCTL_THR0, 16, 4, K210_DIV_ONE_BASED)
> +	},
> +	[K210_CLK_DVP] = {
> +		.name = "dvp",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 3),
> +		K210_DIV(K210_SYSCTL_THR0, 12, 4, K210_DIV_ONE_BASED)
> +	},
> +	[K210_CLK_APB0] = {
> +		.name = "apb0",
> +		K210_GATE(K210_SYSCTL_EN_CENT, 3),
> +		K210_DIV(K210_SYSCTL_SEL0, 3, 3, K210_DIV_ONE_BASED)
> +	},
> +	[K210_CLK_APB1] = {
> +		.name = "apb1",
> +		K210_GATE(K210_SYSCTL_EN_CENT, 4),
> +		K210_DIV(K210_SYSCTL_SEL0, 6, 3, K210_DIV_ONE_BASED)
> +	},
> +	[K210_CLK_APB2] = {
> +		.name = "apb2",
> +		K210_GATE(K210_SYSCTL_EN_CENT, 5),
> +		K210_DIV(K210_SYSCTL_SEL0, 9, 3, K210_DIV_ONE_BASED)
> +	},
> +	[K210_CLK_AI] = {
> +		.name = "ai",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 2),
> +		K210_DIV(K210_SYSCTL_THR0, 8, 4, K210_DIV_ONE_BASED)
> +	},
> +	[K210_CLK_SPI0] = {
> +		.name = "spi0",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 6),
> +		K210_DIV(K210_SYSCTL_THR1, 0, 8, K210_DIV_DOUBLE_ONE_BASED)
> +	},
> +	[K210_CLK_SPI1] = {
> +		.name = "spi1",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 7),
> +		K210_DIV(K210_SYSCTL_THR1, 8, 8, K210_DIV_DOUBLE_ONE_BASED)
> +	},
> +	[K210_CLK_SPI2] = {
> +		.name = "spi2",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 8),
> +		K210_DIV(K210_SYSCTL_THR1, 16, 8, K210_DIV_DOUBLE_ONE_BASED)
> +	},
> +	[K210_CLK_I2C0] = {
> +		.name = "i2c0",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 13),
> +		K210_DIV(K210_SYSCTL_THR5, 8, 8, K210_DIV_DOUBLE_ONE_BASED)
> +	},
> +	[K210_CLK_I2C1] = {
> +		.name = "i2c1",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 14),
> +		K210_DIV(K210_SYSCTL_THR5, 16, 8, K210_DIV_DOUBLE_ONE_BASED)
> +	},
> +	[K210_CLK_I2C2] = {
> +		.name = "i2c2",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 15),
> +		K210_DIV(K210_SYSCTL_THR5, 24, 8, K210_DIV_DOUBLE_ONE_BASED)
> +	},
> +	[K210_CLK_WDT0] = {
> +		.name = "wdt0",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 24),
> +		K210_DIV(K210_SYSCTL_THR6, 0, 8, K210_DIV_DOUBLE_ONE_BASED)
> +	},
> +	[K210_CLK_WDT1] = {
> +		.name = "wdt1",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 25),
> +		K210_DIV(K210_SYSCTL_THR6, 8, 8, K210_DIV_DOUBLE_ONE_BASED)
> +	},
> +	[K210_CLK_I2S0] = {
> +		.name = "i2s0",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 10),
> +		K210_DIV(K210_SYSCTL_THR3, 0, 16, K210_DIV_DOUBLE_ONE_BASED)
> +	},
> +	[K210_CLK_I2S1] = {
> +		.name = "i2s1",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 11),
> +		K210_DIV(K210_SYSCTL_THR3, 16, 16, K210_DIV_DOUBLE_ONE_BASED)
> +	},
> +	[K210_CLK_I2S2] = {
> +		.name = "i2s2",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 12),
> +		K210_DIV(K210_SYSCTL_THR4, 0, 16, K210_DIV_DOUBLE_ONE_BASED)
> +	},
> +
> +	/* Divider clocks, no gate, no mux */
> +	[K210_CLK_I2S0_M] = {
> +		.name = "i2s0_m",
> +		K210_DIV(K210_SYSCTL_THR4, 16, 8, K210_DIV_DOUBLE_ONE_BASED)
> +	},
> +	[K210_CLK_I2S1_M] = {
> +		.name = "i2s1_m",
> +		K210_DIV(K210_SYSCTL_THR4, 24, 8, K210_DIV_DOUBLE_ONE_BASED)
> +	},
> +	[K210_CLK_I2S2_M] = {
> +		.name = "i2s2_m",
> +		K210_DIV(K210_SYSCTL_THR4, 0, 8, K210_DIV_DOUBLE_ONE_BASED)
> +	},
> +
> +	/* Muxed gated divider clocks */
> +	[K210_CLK_SPI3] = {
> +		.name = "spi3",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 9),
> +		K210_DIV(K210_SYSCTL_THR1, 24, 8, K210_DIV_DOUBLE_ONE_BASED),
> +		K210_MUX(K210_SYSCTL_SEL0, 12)
> +	},
> +	[K210_CLK_TIMER0] = {
> +		.name = "timer0",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 21),
> +		K210_DIV(K210_SYSCTL_THR2,  0, 8, K210_DIV_DOUBLE_ONE_BASED),
> +		K210_MUX(K210_SYSCTL_SEL0, 13)
> +	},
> +	[K210_CLK_TIMER1] = {
> +		.name = "timer1",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 22),
> +		K210_DIV(K210_SYSCTL_THR2, 8, 8, K210_DIV_DOUBLE_ONE_BASED),
> +		K210_MUX(K210_SYSCTL_SEL0, 14)
> +	},
> +	[K210_CLK_TIMER2] = {
> +		.name = "timer2",
> +		K210_GATE(K210_SYSCTL_EN_PERI, 23),
> +		K210_DIV(K210_SYSCTL_THR2, 16, 8, K210_DIV_DOUBLE_ONE_BASED),
> +		K210_MUX(K210_SYSCTL_SEL0, 15)
> +	},
> +};
> +
> +/*
> + * PLL control register bits.
> + */
> +#define K210_PLL_CLKR		GENMASK(3, 0)
> +#define K210_PLL_CLKF		GENMASK(9, 4)
> +#define K210_PLL_CLKOD		GENMASK(13, 10)
> +#define K210_PLL_BWADJ		GENMASK(19, 14)
> +#define K210_PLL_RESET		(1 << 20)
> +#define K210_PLL_PWRD		(1 << 21)
> +#define K210_PLL_INTFB		(1 << 22)
> +#define K210_PLL_BYPASS		(1 << 23)
> +#define K210_PLL_TEST		(1 << 24)
> +#define K210_PLL_EN		(1 << 25)
> +#define K210_PLL_SEL		GENMASK(27, 26) /* PLL2 only */
> +
> +/*
> + * PLL lock register bits.
> + */
> +#define K210_PLL_LOCK		0
> +#define K210_PLL_CLEAR_SLIP	2
> +#define K210_PLL_TEST_OUT	3
> +
> +/*
> + * Clock selector register bits.
> + */
> +#define K210_ACLK_SEL		BIT(0)
> +#define K210_ACLK_DIV		GENMASK(2, 1)
> +
> +/*
> + * PLLs.
> + */
> +enum k210_pll_id {
> +	K210_PLL0, K210_PLL1, K210_PLL2, K210_PLL_NUM
> +};
> +
> +struct k210_pll {
> +	enum k210_pll_id id;
> +	struct k210_sysclk *ksc;
> +	void __iomem *base;
> +	void __iomem *reg;
> +	void __iomem *lock;
> +	u8 lock_shift;
> +	u8 lock_width;
> +	struct clk_hw hw;
> +};
> +#define to_k210_pll(_hw)	container_of(_hw, struct k210_pll, hw)
> +
> +/*
> + * PLLs configuration: by default PLL0 runs at 780 MHz and PLL1 at 299 MHz.
> + * The first 2 SRAM banks depend on ACLK/CPU clock which is by default PLL0
> + * rate divided by 2. Set PLL1 to 390 MHz so that the third SRAM bank has the
> + * same clock as the first 2.
> + */
> +struct k210_pll_cfg {
> +	u32 reg;
> +	u8 lock_shift;
> +	u8 lock_width;
> +	u32 r;
> +	u32 f;
> +	u32 od;
> +	u32 bwadj;
> +};
> +
> +static struct k210_pll_cfg k210_plls_cfg[] = {
> +	{ K210_SYSCTL_PLL0,  0, 2, 0, 59, 1, 59 }, /* 780 MHz */
> +	{ K210_SYSCTL_PLL1,  8, 1, 0, 59, 3, 59 }, /* 390 MHz */
> +	{ K210_SYSCTL_PLL2, 16, 1, 0, 22, 1, 22 }, /* 299 MHz */
> +};
> +
> +/**
> + * struct k210_sysclk - sysclk driver data
> + * @node: device node
> + * @regs: system controller registers start address
> + * @clk_lock: clock setting spinlock
> + * @plls: SoC PLLs descriptors
> + * @aclk: ACLK clock
> + * @clks: All other clocks
> + */
> +struct k210_sysclk {
> +	struct device_node		*node;
> +	void __iomem			*regs;
> +	spinlock_t			clk_lock;
> +	struct k210_pll			plls[K210_PLL_NUM];
> +	struct clk_hw			aclk;
> +	struct k210_clk			clks[K210_NUM_CLKS];
> +};
> +
> +#define to_k210_sysclk(_hw)	container_of(_hw, struct k210_sysclk, aclk)
> +
> +/*
> + * Set ACLK parent selector: 0 for IN0, 1 for PLL0.
> + */
> +static void k210_aclk_set_selector(void __iomem *regs, u8 sel)
> +{
> +	u32 reg = readl(regs + K210_SYSCTL_SEL0);
> +
> +	if (sel)
> +		reg |= K210_ACLK_SEL;
> +	else
> +		reg &= K210_ACLK_SEL;
> +	writel(reg, regs + K210_SYSCTL_SEL0);
> +}
> +
> +static void k210_init_pll(void __iomem *regs, enum k210_pll_id pllid,
> +			  struct k210_pll *pll)
> +{
> +	pll->id = pllid;
> +	pll->reg = regs + k210_plls_cfg[pllid].reg;
> +	pll->lock = regs + K210_SYSCTL_PLL_LOCK;
> +	pll->lock_shift = k210_plls_cfg[pllid].lock_shift;
> +	pll->lock_width = k210_plls_cfg[pllid].lock_width;
> +}
> +
> +static void k210_pll_wait_for_lock(struct k210_pll *pll)
> +{
> +	u32 reg, mask = GENMASK(pll->lock_shift + pll->lock_width - 1,
> +				pll->lock_shift);
> +
> +	while (true) {
> +		reg = readl(pll->lock);
> +		if ((reg & mask) == mask)
> +			break;
> +
> +		reg |= BIT(pll->lock_shift + K210_PLL_CLEAR_SLIP);
> +		writel(reg, pll->lock);
> +	}
> +}
> +
> +static bool k210_pll_hw_is_enabled(struct k210_pll *pll)
> +{
> +	u32 reg = readl(pll->reg);
> +	u32 mask = K210_PLL_PWRD | K210_PLL_EN;
> +
> +	if (reg & K210_PLL_RESET)
> +		return false;
> +
> +	return (reg & mask) == mask;
> +}
> +
> +static void k210_pll_enable_hw(void __iomem *regs, struct k210_pll *pll)
> +{
> +	struct k210_pll_cfg *pll_cfg = &k210_plls_cfg[pll->id];
> +	u32 reg;
> +
> +	if (k210_pll_hw_is_enabled(pll))
> +		return;
> +
> +	/*
> +	 * For PLL0, we need to re-parent ACLK to IN0 to keep the CPU cores and
> +	 * SRAM running.
> +	 */
> +	if (pll->id == K210_PLL0)
> +		k210_aclk_set_selector(regs, 0);
> +
> +	/* Set PLL factors */
> +	reg = readl(pll->reg);
> +	reg &= ~GENMASK(19, 0);
> +	reg |= FIELD_PREP(K210_PLL_CLKR, pll_cfg->r);
> +	reg |= FIELD_PREP(K210_PLL_CLKF, pll_cfg->f);
> +	reg |= FIELD_PREP(K210_PLL_CLKOD, pll_cfg->od);
> +	reg |= FIELD_PREP(K210_PLL_BWADJ, pll_cfg->bwadj);
> +	reg |= K210_PLL_PWRD;
> +	writel(reg, pll->reg);
> +
> +	/*
> +	 * Reset the PLL: ensure reset is low before asserting it.
> +	 * The magic NOPs come from the Kendryte reference SDK.
> +	 */
> +	reg &= ~K210_PLL_RESET;
> +	writel(reg, pll->reg);
> +	reg |= K210_PLL_RESET;
> +	writel(reg, pll->reg);
> +	nop();
> +	nop();
> +	reg &= ~K210_PLL_RESET;
> +	writel(reg, pll->reg);
> +
> +	k210_pll_wait_for_lock(pll);
> +
> +	reg &= ~K210_PLL_BYPASS;
> +	reg |= K210_PLL_EN;
> +	writel(reg, pll->reg);
> +
> +	if (pll->id == K210_PLL0)
> +		k210_aclk_set_selector(regs, 1);
> +}
> +
> +static int k210_pll_enable(struct clk_hw *hw)
> +{
> +	struct k210_pll *pll = to_k210_pll(hw);
> +	struct k210_sysclk *ksc = pll->ksc;
> +	unsigned long flags;
> +
> +	spin_lock_irqsave(&ksc->clk_lock, flags);
> +
> +	k210_pll_enable_hw(ksc->regs, pll);
> +
> +	spin_unlock_irqrestore(&ksc->clk_lock, flags);
> +
> +	return 0;
> +}
> +
> +static void k210_pll_disable(struct clk_hw *hw)
> +{
> +	struct k210_pll *pll = to_k210_pll(hw);
> +	struct k210_sysclk *ksc = pll->ksc;
> +	unsigned long flags;
> +	u32 reg;
> +
> +	/*
> +	 * Bypassing before powering off is important so child clocks do not
> +	 * stop working. This is especially important for pll0, the indirect
> +	 * parent of the cpu clock.
> +	 */
> +	spin_lock_irqsave(&ksc->clk_lock, flags);
> +	reg = readl(pll->reg);
> +	reg |= K210_PLL_BYPASS;
> +	writel(reg, pll->reg);
> +
> +	reg &= ~K210_PLL_PWRD;
> +	reg &= ~K210_PLL_EN;
> +	writel(reg, pll->reg);
> +	spin_unlock_irqrestore(&ksc->clk_lock, flags);
> +}
> +
> +static int k210_pll_is_enabled(struct clk_hw *hw)
> +{
> +	return k210_pll_hw_is_enabled(to_k210_pll(hw));
> +}
> +
> +static unsigned long k210_pll_get_rate(struct clk_hw *hw,
> +				       unsigned long parent_rate)
> +{
> +	struct k210_pll *pll = to_k210_pll(hw);
> +	u32 reg = readl(pll->reg);
> +	u32 r, f, od;
> +
> +	if (reg & K210_PLL_BYPASS)
> +		return parent_rate;
> +
> +	if (!(reg & K210_PLL_PWRD))
> +		return 0;
> +
> +	r = FIELD_GET(K210_PLL_CLKR, reg) + 1;
> +	f = FIELD_GET(K210_PLL_CLKF, reg) + 1;
> +	od = FIELD_GET(K210_PLL_CLKOD, reg) + 1;
> +
> +	return (u64)parent_rate * f / (r * od);
> +}
> +
> +static const struct clk_ops k210_pll_ops = {
> +	.enable		= k210_pll_enable,
> +	.disable	= k210_pll_disable,
> +	.is_enabled	= k210_pll_is_enabled,
> +	.recalc_rate	= k210_pll_get_rate,
> +};
> +
> +static int k210_pll2_set_parent(struct clk_hw *hw, u8 index)
> +{
> +	struct k210_pll *pll = to_k210_pll(hw);
> +	struct k210_sysclk *ksc = pll->ksc;
> +	unsigned long flags;
> +	u32 reg;
> +
> +	spin_lock_irqsave(&ksc->clk_lock, flags);
> +
> +	reg = readl(pll->reg);
> +	reg &= ~K210_PLL_SEL;
> +	reg |= FIELD_PREP(K210_PLL_SEL, index);
> +	writel(reg, pll->reg);
> +
> +	spin_unlock_irqrestore(&ksc->clk_lock, flags);
> +
> +	return 0;
> +}
> +
> +static u8 k210_pll2_get_parent(struct clk_hw *hw)
> +{
> +	struct k210_pll *pll = to_k210_pll(hw);
> +	u32 reg = readl(pll->reg);
> +
> +	return FIELD_GET(K210_PLL_SEL, reg);
> +}
> +
> +static const struct clk_ops k210_pll2_ops = {
> +	.enable		= k210_pll_enable,
> +	.disable	= k210_pll_disable,
> +	.is_enabled	= k210_pll_is_enabled,
> +	.recalc_rate	= k210_pll_get_rate,
> +	.set_parent	= k210_pll2_set_parent,
> +	.get_parent	= k210_pll2_get_parent,
> +};
> +
> +static int k210_register_pll(struct k210_sysclk *ksc, const char *in0,
> +			     enum k210_pll_id pllid, const char *name,
> +			     int num_parents, const struct clk_ops *ops)
> +{
> +	struct k210_pll *pll = &ksc->plls[pllid];
> +	struct clk_init_data init = {};
> +	const struct clk_parent_data parent_data[] = {
> +		{ .name = in0 },
> +		{ .hw = &ksc->plls[K210_PLL0].hw },
> +		{ .hw = &ksc->plls[K210_PLL1].hw },
> +	};
> +
> +	init.name = name;
> +	init.parent_data = parent_data;
> +	init.num_parents = num_parents;
> +	init.ops = ops;
> +
> +	pll->hw.init = &init;
> +	pll->ksc = ksc;
> +
> +	return clk_hw_register(NULL, &pll->hw);
> +}
> +
> +static int k210_register_plls(struct k210_sysclk *ksc, const char *in0)
> +{
> +	int i, ret;
> +
> +	for (i = 0; i < K210_PLL_NUM; i++)
> +		k210_init_pll(ksc->regs, i, &ksc->plls[i]);
> +
> +	/* PLL0 and PLL1 only have IN0 as parent */
> +	ret = k210_register_pll(ksc, in0, K210_PLL0, "pll0", 1, &k210_pll_ops);
> +	if (ret) {
> +		pr_err("%pOFP: register PLL0 failed\n", ksc->node);
> +		return ret;
> +	}
> +	ret = k210_register_pll(ksc, in0, K210_PLL1, "pll1", 1, &k210_pll_ops);
> +	if (ret) {
> +		pr_err("%pOFP: register PLL1 failed\n", ksc->node);
> +		return ret;
> +	}
> +
> +	/* PLL2 has IN0, PLL0 and PLL1 as parents */
> +	ret = k210_register_pll(ksc, in0, K210_PLL2, "pll2", 3, &k210_pll2_ops);
> +	if (ret) {
> +		pr_err("%pOFP: register PLL2 failed\n", ksc->node);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int k210_aclk_set_parent(struct clk_hw *hw, u8 index)
> +{
> +	struct k210_sysclk *ksc = to_k210_sysclk(hw);
> +	unsigned long flags;
> +
> +	spin_lock_irqsave(&ksc->clk_lock, flags);
> +
> +	k210_aclk_set_selector(ksc->regs, index);
> +
> +	spin_unlock_irqrestore(&ksc->clk_lock, flags);
> +
> +	return 0;
> +}
> +
> +static u8 k210_aclk_get_parent(struct clk_hw *hw)
> +{
> +	struct k210_sysclk *ksc = to_k210_sysclk(hw);
> +	u32 sel;
> +
> +	sel = readl(ksc->regs + K210_SYSCTL_SEL0) & K210_ACLK_SEL;
> +
> +	return sel ? 1 : 0;
> +}
> +
> +static unsigned long k210_aclk_get_rate(struct clk_hw *hw,
> +					unsigned long parent_rate)
> +{
> +	struct k210_sysclk *ksc = to_k210_sysclk(hw);
> +	u32 reg = readl(ksc->regs + K210_SYSCTL_SEL0);
> +	unsigned int shift;
> +
> +	if (!(reg & 0x1))
> +		return parent_rate;
> +
> +	shift = FIELD_GET(K210_ACLK_DIV, reg);
> +
> +	return parent_rate / (2UL << shift);
> +}
> +
> +static const struct clk_ops k210_aclk_ops = {
> +	.set_parent	= k210_aclk_set_parent,
> +	.get_parent	= k210_aclk_get_parent,
> +	.recalc_rate	= k210_aclk_get_rate,
> +};
> +
> +/*
> + * ACLK has IN0 and PLL0 as parents.
> + */
> +static int k210_register_aclk(struct k210_sysclk *ksc, const char *in0)
> +{
> +	struct clk_init_data init = {};
> +	const struct clk_parent_data parent_data[] = {
> +		{ .name = in0 },
> +		{ .hw = &ksc->plls[K210_PLL0].hw },
> +	};
> +	int ret;
> +
> +	init.name = "aclk";
> +	init.parent_data = parent_data;
> +	init.num_parents = 2;
> +	init.ops = &k210_aclk_ops;
> +	ksc->aclk.init = &init;
> +
> +	ret = clk_hw_register(NULL, &ksc->aclk);
> +	if (ret) {
> +		pr_err("%pOFP: register aclk failed\n", ksc->node);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +#define to_k210_clk(_hw)	container_of(_hw, struct k210_clk, hw)
> +
> +static int k210_clk_enable(struct clk_hw *hw)
> +{
> +	struct k210_clk *kclk = to_k210_clk(hw);
> +	struct k210_sysclk *ksc = kclk->ksc;
> +	struct k210_clk_cfg *cfg = &k210_clk_cfgs[kclk->id];
> +	unsigned long flags;
> +	u32 reg;
> +
> +	if (!cfg->gate_reg)
> +		return 0;
> +
> +	spin_lock_irqsave(&ksc->clk_lock, flags);
> +	reg = readl(ksc->regs + cfg->gate_reg);
> +	reg |= BIT(cfg->gate_bit);
> +	writel(reg, ksc->regs + cfg->gate_reg);
> +	spin_unlock_irqrestore(&ksc->clk_lock, flags);
> +
> +	return 0;
> +}
> +
> +static void k210_clk_disable(struct clk_hw *hw)
> +{
> +	struct k210_clk *kclk = to_k210_clk(hw);
> +	struct k210_sysclk *ksc = kclk->ksc;
> +	struct k210_clk_cfg *cfg = &k210_clk_cfgs[kclk->id];
> +	unsigned long flags;
> +	u32 reg;
> +
> +	if (!cfg->gate_reg)
> +		return;
> +
> +	spin_lock_irqsave(&ksc->clk_lock, flags);
> +	reg = readl(ksc->regs + cfg->gate_reg);
> +	reg &= ~BIT(cfg->gate_bit);
> +	writel(reg, ksc->regs + cfg->gate_reg);
> +	spin_unlock_irqrestore(&ksc->clk_lock, flags);
> +}
> +
> +static int k210_clk_set_parent(struct clk_hw *hw, u8 index)
> +{
> +	struct k210_clk *kclk = to_k210_clk(hw);
> +	struct k210_sysclk *ksc = kclk->ksc;
> +	struct k210_clk_cfg *cfg = &k210_clk_cfgs[kclk->id];
> +	unsigned long flags;
> +	u32 reg;
> +
> +	spin_lock_irqsave(&ksc->clk_lock, flags);
> +	reg = readl(ksc->regs + cfg->mux_reg);
> +	if (index)
> +		reg |= BIT(cfg->mux_bit);
> +	else
> +		reg &= ~BIT(cfg->mux_bit);
> +	spin_unlock_irqrestore(&ksc->clk_lock, flags);
> +
> +	return 0;
> +}
> +
> +static u8 k210_clk_get_parent(struct clk_hw *hw)
> +{
> +	struct k210_clk *kclk = to_k210_clk(hw);
> +	struct k210_sysclk *ksc = kclk->ksc;
> +	struct k210_clk_cfg *cfg = &k210_clk_cfgs[kclk->id];
> +	unsigned long flags;
> +	u32 reg, idx;
> +
> +	spin_lock_irqsave(&ksc->clk_lock, flags);
> +	reg = readl(ksc->regs + cfg->mux_reg);
> +	idx = (reg & BIT(cfg->mux_bit)) ? 1 : 0;
> +	spin_unlock_irqrestore(&ksc->clk_lock, flags);
> +
> +	return idx;
> +}
> +
> +static unsigned long k210_clk_get_rate(struct clk_hw *hw,
> +				       unsigned long parent_rate)
> +{
> +	struct k210_clk *kclk = to_k210_clk(hw);
> +	struct k210_sysclk *ksc = kclk->ksc;
> +	struct k210_clk_cfg *cfg = &k210_clk_cfgs[kclk->id];
> +	u32 reg, div_val;
> +
> +	if (!cfg->div_reg)
> +		return parent_rate;
> +
> +	reg = readl(ksc->regs + cfg->div_reg);
> +	div_val = (reg >> cfg->div_shift) & GENMASK(cfg->div_width - 1, 0);
> +
> +	switch (cfg->div_type) {
> +	case K210_DIV_ONE_BASED:
> +		return parent_rate / (div_val + 1);
> +	case K210_DIV_DOUBLE_ONE_BASED:
> +		return parent_rate / ((div_val + 1) * 2);
> +	case K210_DIV_POWER_OF_TWO:
> +		return parent_rate / (2UL << div_val);
> +	case K210_DIV_NONE:
> +	default:
> +		return 0;
> +	}
> +}
> +
> +static const struct clk_ops k210_clk_mux_ops = {
> +	.enable		= k210_clk_enable,
> +	.disable	= k210_clk_disable,
> +	.set_parent	= k210_clk_set_parent,
> +	.get_parent	= k210_clk_get_parent,
> +	.recalc_rate	= k210_clk_get_rate,
> +};
> +
> +static const struct clk_ops k210_clk_ops = {
> +	.enable		= k210_clk_enable,
> +	.disable	= k210_clk_disable,
> +	.recalc_rate	= k210_clk_get_rate,
> +};
> +
> +static void k210_register_clk(struct k210_sysclk *ksc, int id,
> +			      const struct clk_parent_data *parent_data,
> +			      int num_parents, unsigned long flags)
> +{
> +	struct k210_clk *kclk = &ksc->clks[id];
> +	struct clk_init_data init = {};
> +	int ret;
> +
> +	init.name = k210_clk_cfgs[id].name;
> +	init.flags = flags;
> +	init.parent_data = parent_data;
> +	init.num_parents = num_parents;
> +	if (num_parents > 1)
> +		init.ops = &k210_clk_mux_ops;
> +	else
> +		init.ops = &k210_clk_ops;
> +
> +	kclk->id = id;
> +	kclk->ksc = ksc;
> +	kclk->hw.init = &init;
> +
> +	ret = clk_hw_register(NULL, &kclk->hw);
> +	if (ret) {
> +		pr_err("%pOFP: register clock %s failed\n",
> +		       ksc->node, k210_clk_cfgs[id].name);
> +		kclk->id = -1;
> +	}
> +}
> +
> +/*
> + * All muxed clocks have IN0 and PLL0 as parents.
> + */
> +static inline void k210_register_mux_clk(struct k210_sysclk *ksc,
> +					 const char *in0, int id)
> +{
> +	const struct clk_parent_data parent_data[2] = {
> +		{ .name = in0 },
> +		{ .hw = &ksc->plls[K210_PLL0].hw },
> +	};
> +
> +	k210_register_clk(ksc, id, parent_data, 2, 0);
> +}
> +
> +static inline void k210_register_in0_child(struct k210_sysclk *ksc,
> +					   const char *in0, int id)
> +{
> +	const struct clk_parent_data parent_data = {
> +		.name = in0,
> +	};
> +
> +	k210_register_clk(ksc, id, &parent_data, 1, 0);
> +}
> +
> +static inline void k210_register_pll_child(struct k210_sysclk *ksc, int id,
> +					   enum k210_pll_id pllid,
> +					   unsigned long flags)
> +{
> +	const struct clk_parent_data parent_data = {
> +		.hw = &ksc->plls[pllid].hw,
> +	};
> +
> +	k210_register_clk(ksc, id, &parent_data, 1, flags);
> +}
> +
> +static inline void k210_register_aclk_child(struct k210_sysclk *ksc, int id,
> +					    unsigned long flags)
> +{
> +	const struct clk_parent_data parent_data = {
> +		.hw = &ksc->aclk,
> +	};
> +
> +	k210_register_clk(ksc, id, &parent_data, 1, flags);
> +}
> +
> +static inline void k210_register_clk_child(struct k210_sysclk *ksc, int id,
> +					   int parent_id)
> +{
> +	const struct clk_parent_data parent_data = {
> +		.hw = &ksc->clks[parent_id].hw,
> +	};
> +
> +	k210_register_clk(ksc, id, &parent_data, 1, 0);
> +}
> +
> +static struct clk_hw *k210_clk_hw_onecell_get(struct of_phandle_args *clkspec,
> +					      void *data)
> +{
> +	struct k210_sysclk *ksc = data;
> +	unsigned int idx = clkspec->args[0];
> +
> +	if (idx >= K210_NUM_CLKS)
> +		return ERR_PTR(-EINVAL);
> +
> +	return &ksc->clks[idx].hw;
> +}
> +
> +static void __init k210_clk_init(struct device_node *np)
> +{
> +	struct device_node *sysctl_np;
> +	struct k210_sysclk *ksc;
> +	const char *in0;
> +	int i, ret;
> +
> +	ksc = kzalloc(sizeof(*ksc), GFP_KERNEL);
> +	if (!ksc)
> +		return;
> +
> +	ksc->node = np;
> +	spin_lock_init(&ksc->clk_lock);
> +	sysctl_np = of_get_parent(np);
> +	ksc->regs = of_iomap(sysctl_np, 0);
> +	of_node_put(sysctl_np);
> +	if (!ksc->regs) {
> +		pr_err("%pOFP: failed to map registers\n", np);
> +		return;
> +	}
> +
> +	in0 = of_clk_get_parent_name(np, 0);
> +	if (!in0) {
> +		pr_err("%pOFP: undefined fixed-rate oscillator clock\n", np);
> +		return;
> +	}
> +
> +	ret = k210_register_plls(ksc, in0);
> +	if (ret)
> +		return;
> +
> +	ret = k210_register_aclk(ksc, in0);
> +	if (ret)
> +		return;
> +
> +	/*
> +	 * Critical clocks: there are no consumers of the SRAM clocks,
> +	 * including the AI clock for the third SRAM bank. The CPU clock
> +	 * is only referenced by the uarths serial device and so would be
> +	 * disabled if the serial console is disabled to switch to another
> +	 * console. Mark all these clocks as critical so that they are never
> +	 * disabled by the core clock management.
> +	 */
> +	k210_register_aclk_child(ksc, K210_CLK_CPU, CLK_IS_CRITICAL);
> +	k210_register_aclk_child(ksc, K210_CLK_SRAM0, CLK_IS_CRITICAL);
> +	k210_register_aclk_child(ksc, K210_CLK_SRAM1, CLK_IS_CRITICAL);
> +	k210_register_pll_child(ksc, K210_CLK_AI, K210_PLL1, CLK_IS_CRITICAL);
> +
> +	/* Clocks with aclk as source */
> +	k210_register_aclk_child(ksc, K210_CLK_DMA, 0);
> +	k210_register_aclk_child(ksc, K210_CLK_FFT, 0);
> +	k210_register_aclk_child(ksc, K210_CLK_ROM, 0);
> +	k210_register_aclk_child(ksc, K210_CLK_DVP, 0);
> +	k210_register_aclk_child(ksc, K210_CLK_APB0, 0);
> +	k210_register_aclk_child(ksc, K210_CLK_APB1, 0);
> +	k210_register_aclk_child(ksc, K210_CLK_APB2, 0);
> +
> +	/* Clocks with PLL0 as source */
> +	k210_register_pll_child(ksc, K210_CLK_SPI0, K210_PLL0, 0);
> +	k210_register_pll_child(ksc, K210_CLK_SPI1, K210_PLL0, 0);
> +	k210_register_pll_child(ksc, K210_CLK_SPI2, K210_PLL0, 0);
> +	k210_register_pll_child(ksc, K210_CLK_I2C0, K210_PLL0, 0);
> +	k210_register_pll_child(ksc, K210_CLK_I2C1, K210_PLL0, 0);
> +	k210_register_pll_child(ksc, K210_CLK_I2C2, K210_PLL0, 0);
> +
> +	/* Clocks with PLL2 as source */
> +	k210_register_pll_child(ksc, K210_CLK_I2S0, K210_PLL2, 0);
> +	k210_register_pll_child(ksc, K210_CLK_I2S1, K210_PLL2, 0);
> +	k210_register_pll_child(ksc, K210_CLK_I2S2, K210_PLL2, 0);
> +	k210_register_pll_child(ksc, K210_CLK_I2S0_M, K210_PLL2, 0);
> +	k210_register_pll_child(ksc, K210_CLK_I2S1_M, K210_PLL2, 0);
> +	k210_register_pll_child(ksc, K210_CLK_I2S2_M, K210_PLL2, 0);
> +
> +	/* Clocks with IN0 as source */
> +	k210_register_in0_child(ksc, in0, K210_CLK_WDT0);
> +	k210_register_in0_child(ksc, in0, K210_CLK_WDT1);
> +	k210_register_in0_child(ksc, in0, K210_CLK_RTC);
> +
> +	/* Clocks with APB0 as source */
> +	k210_register_clk_child(ksc, K210_CLK_GPIO, K210_CLK_APB0);
> +	k210_register_clk_child(ksc, K210_CLK_UART1, K210_CLK_APB0);
> +	k210_register_clk_child(ksc, K210_CLK_UART2, K210_CLK_APB0);
> +	k210_register_clk_child(ksc, K210_CLK_UART3, K210_CLK_APB0);
> +	k210_register_clk_child(ksc, K210_CLK_FPIOA, K210_CLK_APB0);
> +	k210_register_clk_child(ksc, K210_CLK_SHA, K210_CLK_APB0);
> +
> +	/* Clocks with APB1 as source */
> +	k210_register_clk_child(ksc, K210_CLK_AES, K210_CLK_APB1);
> +	k210_register_clk_child(ksc, K210_CLK_OTP, K210_CLK_APB1);
> +
> +	/* Mux clocks with in0 or pll0 as source */
> +	k210_register_mux_clk(ksc, in0, K210_CLK_SPI3);
> +	k210_register_mux_clk(ksc, in0, K210_CLK_TIMER0);
> +	k210_register_mux_clk(ksc, in0, K210_CLK_TIMER1);
> +	k210_register_mux_clk(ksc, in0, K210_CLK_TIMER2);
> +
> +	/* Check for registration errors */
> +	for (i = 0; i < K210_NUM_CLKS; i++) {
> +		if (ksc->clks[i].id != i)
> +			return;
> +	}
> +
> +	ret = of_clk_add_hw_provider(np, k210_clk_hw_onecell_get, ksc);
> +	if (ret) {
> +		pr_err("%pOFP: add clock provider failed %d\n", np, ret);
> +		return;
> +	}
> +
> +	pr_info("%pOFP: CPU running at %lu MHz\n",
> +		np, clk_hw_get_rate(&ksc->clks[K210_CLK_CPU].hw) / 1000000);
> +}
> +
> +CLK_OF_DECLARE(k210_clk, "canaan,k210-clk", k210_clk_init);
> +
> +/*
> + * Enable PLL1 to be able to use the AI SRAM.
> + */
> +void __init k210_clk_early_init(void __iomem *regs)
> +{
> +	struct k210_pll pll1;
> +
> +	/* Make sure ACLK selector is set to PLL0 */
> +	k210_aclk_set_selector(regs, 1);
> +
> +	/* Startup PLL1 to enable the aisram bank for general memory use */
> +	k210_init_pll(regs, K210_PLL1, &pll1);
> +	k210_pll_enable_hw(regs, &pll1);
> +}
> diff --git a/drivers/soc/canaan/Kconfig b/drivers/soc/canaan/Kconfig
> index 5232d13f07e5..8179b69518b4 100644
> --- a/drivers/soc/canaan/Kconfig
> +++ b/drivers/soc/canaan/Kconfig
> @@ -1,14 +1,12 @@
>  # SPDX-License-Identifier: GPL-2.0
>  
> -if SOC_CANAAN
> -
> -config K210_SYSCTL
> +config SOC_K210_SYSCTL
>  	bool "Canaan Kendryte K210 SoC system controller"
> -	default y
> -	depends on RISCV
> +	depends on RISCV && SOC_CANAAN && OF
> +	default SOC_CANAAN
> +        select PM
> +        select SIMPLE_PM_BUS
> +        select SYSCON
> +        select MFD_SYSCON
>  	help
> -	  Enables controlling the K210 various clocks and to enable
> -	  general purpose use of the extra 2MB of SRAM normally
> -	  reserved for the AI engine.
> -
> -endif
> +	  Canaan Kendryte K210 SoC system controller driver.
> diff --git a/drivers/soc/canaan/Makefile b/drivers/soc/canaan/Makefile
> index 002d9ce95c0d..570280ad7967 100644
> --- a/drivers/soc/canaan/Makefile
> +++ b/drivers/soc/canaan/Makefile
> @@ -1,3 +1,3 @@
>  # SPDX-License-Identifier: GPL-2.0
>  
> -obj-$(CONFIG_K210_SYSCTL)	+= k210-sysctl.o
> +obj-$(CONFIG_SOC_K210_SYSCTL)	+= k210-sysctl.o
> diff --git a/drivers/soc/canaan/k210-sysctl.c b/drivers/soc/canaan/k210-sysctl.c
> index 60b474c33d45..27a346c406bc 100644
> --- a/drivers/soc/canaan/k210-sysctl.c
> +++ b/drivers/soc/canaan/k210-sysctl.c
> @@ -3,165 +3,45 @@
>   * Copyright (c) 2019 Christoph Hellwig.
>   * Copyright (c) 2019 Western Digital Corporation or its affiliates.
>   */
> -#include <linux/types.h>
>  #include <linux/io.h>
> -#include <linux/of.h>
>  #include <linux/platform_device.h>
> -#include <linux/clk-provider.h>
> -#include <linux/clkdev.h>
> -#include <linux/bitfield.h>
> +#include <linux/of_platform.h>
> +#include <linux/clk.h>
>  #include <asm/soc.h>
>  
>  #include <soc/canaan/k210-sysctl.h>
>  
> -#define K210_SYSCTL_CLK0_FREQ		26000000UL
> -
> -/* Registers base address */
> -#define K210_SYSCTL_SYSCTL_BASE_ADDR	0x50440000ULL
> -
> -/* Register bits */
> -/* K210_SYSCTL_PLL1: clkr: 4bits, clkf1: 6bits, clkod: 4bits, bwadj: 4bits */
> -#define PLL_RESET		(1 << 20)
> -#define PLL_PWR			(1 << 21)
> -#define PLL_BYPASS		(1 << 23)
> -#define PLL_OUT_EN		(1 << 25)
> -/* K210_SYSCTL_PLL_LOCK */
> -#define PLL1_LOCK1		(1 << 8)
> -#define PLL1_LOCK2		(1 << 9)
> -#define PLL1_SLIP_CLEAR		(1 << 10)
> -/* K210_SYSCTL_SEL0 */
> -#define CLKSEL_ACLK		(1 << 0)
> -/* K210_SYSCTL_CLKEN_CENT */
> -#define CLKEN_CPU		(1 << 0)
> -#define CLKEN_SRAM0		(1 << 1)
> -#define CLKEN_SRAM1		(1 << 2)
> -/* K210_SYSCTL_EN_PERI */
> -#define CLKEN_ROM		(1 << 0)
> -#define CLKEN_TIMER0		(1 << 21)
> -#define CLKEN_RTC		(1 << 29)
> -
> -struct k210_sysctl {
> -	void __iomem		*regs;
> -	struct clk_hw		hw;
> -};
> -
> -static void k210_set_bits(u32 val, void __iomem *reg)
> -{
> -	writel(readl(reg) | val, reg);
> -}
> -
> -static void k210_clear_bits(u32 val, void __iomem *reg)
> -{
> -	writel(readl(reg) & ~val, reg);
> -}
> -
> -static void k210_pll1_enable(void __iomem *regs)
> -{
> -	u32 val;
> -
> -	val = readl(regs + K210_SYSCTL_PLL1);
> -	val &= ~GENMASK(19, 0);				/* clkr1 = 0 */
> -	val |= FIELD_PREP(GENMASK(9, 4), 0x3B);		/* clkf1 = 59 */
> -	val |= FIELD_PREP(GENMASK(13, 10), 0x3);	/* clkod1 = 3 */
> -	val |= FIELD_PREP(GENMASK(19, 14), 0x3B);	/* bwadj1 = 59 */
> -	writel(val, regs + K210_SYSCTL_PLL1);
> -
> -	k210_clear_bits(PLL_BYPASS, regs + K210_SYSCTL_PLL1);
> -	k210_set_bits(PLL_PWR, regs + K210_SYSCTL_PLL1);
> -
> -	/*
> -	 * Reset the pll. The magic NOPs come from the Kendryte reference SDK.
> -	 */
> -	k210_clear_bits(PLL_RESET, regs + K210_SYSCTL_PLL1);
> -	k210_set_bits(PLL_RESET, regs + K210_SYSCTL_PLL1);
> -	nop();
> -	nop();
> -	k210_clear_bits(PLL_RESET, regs + K210_SYSCTL_PLL1);
> -
> -	for (;;) {
> -		val = readl(regs + K210_SYSCTL_PLL_LOCK);
> -		if (val & PLL1_LOCK2)
> -			break;
> -		writel(val | PLL1_SLIP_CLEAR, regs + K210_SYSCTL_PLL_LOCK);
> -	}
> -
> -	k210_set_bits(PLL_OUT_EN, regs + K210_SYSCTL_PLL1);
> -}
> -
> -static unsigned long k210_sysctl_clk_recalc_rate(struct clk_hw *hw,
> -		unsigned long parent_rate)
> -{
> -	struct k210_sysctl *s = container_of(hw, struct k210_sysctl, hw);
> -	u32 clksel0, pll0;
> -	u64 pll0_freq, clkr0, clkf0, clkod0;
> -
> -	/*
> -	 * If the clock selector is not set, use the base frequency.
> -	 * Otherwise, use PLL0 frequency with a frequency divisor.
> -	 */
> -	clksel0 = readl(s->regs + K210_SYSCTL_SEL0);
> -	if (!(clksel0 & CLKSEL_ACLK))
> -		return K210_SYSCTL_CLK0_FREQ;
> -
> -	/*
> -	 * Get PLL0 frequency:
> -	 * freq = base frequency * clkf0 / (clkr0 * clkod0)
> -	 */
> -	pll0 = readl(s->regs + K210_SYSCTL_PLL0);
> -	clkr0 = 1 + FIELD_GET(GENMASK(3, 0), pll0);
> -	clkf0 = 1 + FIELD_GET(GENMASK(9, 4), pll0);
> -	clkod0 = 1 + FIELD_GET(GENMASK(13, 10), pll0);
> -	pll0_freq = clkf0 * K210_SYSCTL_CLK0_FREQ / (clkr0 * clkod0);
> -
> -	/* Get the frequency divisor from the clock selector */
> -	return pll0_freq / (2ULL << FIELD_GET(0x00000006, clksel0));
> -}
> -
> -static const struct clk_ops k210_sysctl_clk_ops = {
> -	.recalc_rate	= k210_sysctl_clk_recalc_rate,
> -};
> -
> -static const struct clk_init_data k210_clk_init_data = {
> -	.name		= "k210-sysctl-pll1",
> -	.ops		= &k210_sysctl_clk_ops,
> -};
> -
>  static int k210_sysctl_probe(struct platform_device *pdev)
>  {
> -	struct k210_sysctl *s;
> -	int error;
> -
> -	pr_info("Kendryte K210 SoC sysctl\n");
> -
> -	s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL);
> -	if (!s)
> -		return -ENOMEM;
> -
> -	s->regs = devm_ioremap_resource(&pdev->dev,
> -			platform_get_resource(pdev, IORESOURCE_MEM, 0));
> -	if (IS_ERR(s->regs))
> -		return PTR_ERR(s->regs);
> -
> -	s->hw.init = &k210_clk_init_data;
> -	error = devm_clk_hw_register(&pdev->dev, &s->hw);
> -	if (error) {
> -		dev_err(&pdev->dev, "failed to register clk");
> -		return error;
> +	struct device *dev = &pdev->dev;
> +	struct clk *pclk;
> +	int ret;
> +
> +	dev_info(dev, "K210 system controller\n");
> +
> +	/* Get power bus clock */
> +	pclk = devm_clk_get(dev, NULL);
> +	if (IS_ERR(pclk))
> +		return dev_err_probe(dev, PTR_ERR(pclk),
> +				     "Get bus clock failed\n");
> +
> +	ret = clk_prepare_enable(pclk);
> +	if (ret) {
> +		dev_err(dev, "Enable bus clock failed\n");
> +		return ret;
>  	}
>  
> -	error = devm_of_clk_add_hw_provider(&pdev->dev, of_clk_hw_simple_get,
> -					    &s->hw);
> -	if (error) {
> -		dev_err(&pdev->dev, "adding clk provider failed\n");
> -		return error;
> -	}
> +	/* Populate children */
> +	ret = devm_of_platform_populate(dev);
> +	if (ret)
> +		dev_err(dev, "Populate platform failed %d\n", ret);
>  
> -	return 0;
> +	return ret;
>  }
>  
>  static const struct of_device_id k210_sysctl_of_match[] = {
> -	{ .compatible = "kendryte,k210-sysctl", },
> -	{}
> +	{ .compatible = "canaan,k210-sysctl", },
> +	{ /* sentinel */ },
>  };
>  
>  static struct platform_driver k210_sysctl_driver = {
> @@ -171,12 +51,13 @@ static struct platform_driver k210_sysctl_driver = {
>  	},
>  	.probe			= k210_sysctl_probe,
>  };
> +builtin_platform_driver(k210_sysctl_driver);
>  
> -static int __init k210_sysctl_init(void)
> -{
> -	return platform_driver_register(&k210_sysctl_driver);
> -}
> -core_initcall(k210_sysctl_init);
> +/*
> + * System controller registers base address and size.
> + */
> +#define K210_SYSCTL_BASE_ADDR	0x50440000ULL
> +#define K210_SYSCTL_BASE_SIZE	0x1000
>  
>  /*
>   * This needs to be called very early during initialization, given that
> @@ -184,24 +65,14 @@ core_initcall(k210_sysctl_init);
>   */
>  static void __init k210_soc_early_init(const void *fdt)
>  {
> -	void __iomem *regs;
> -
> -	regs = ioremap(K210_SYSCTL_SYSCTL_BASE_ADDR, 0x1000);
> -	if (!regs)
> -		panic("K210 sysctl ioremap");
> -
> -	/* Enable PLL1 to make the KPU SRAM useable */
> -	k210_pll1_enable(regs);
> -
> -	k210_set_bits(PLL_OUT_EN, regs + K210_SYSCTL_PLL0);
> +	void __iomem *sysctl_base;
>  
> -	k210_set_bits(CLKEN_CPU | CLKEN_SRAM0 | CLKEN_SRAM1,
> -		      regs + K210_SYSCTL_EN_CENT);
> -	k210_set_bits(CLKEN_ROM | CLKEN_TIMER0 | CLKEN_RTC,
> -		      regs + K210_SYSCTL_EN_PERI);
> +	sysctl_base = ioremap(K210_SYSCTL_BASE_ADDR, K210_SYSCTL_BASE_SIZE);
> +	if (!sysctl_base)
> +		panic("k210-sysctl: ioremap failed");
>  
> -	k210_set_bits(CLKSEL_ACLK, regs + K210_SYSCTL_SEL0);
> +	k210_clk_early_init(sysctl_base);
>  
> -	iounmap(regs);
> +	iounmap(sysctl_base);
>  }
> -SOC_EARLY_INIT_DECLARE(generic_k210, "kendryte,k210", k210_soc_early_init);
> +SOC_EARLY_INIT_DECLARE(k210_soc, "canaan,kendryte-k210", k210_soc_early_init);
> diff --git a/include/soc/canaan/k210-sysctl.h b/include/soc/canaan/k210-sysctl.h
> index 2e037db68f35..0c2b2c2dabca 100644
> --- a/include/soc/canaan/k210-sysctl.h
> +++ b/include/soc/canaan/k210-sysctl.h
> @@ -38,4 +38,6 @@
>  #define K210_SYSCTL_DMA_SEL1	0x68 /* DMA handshake selector 1 */
>  #define K210_SYSCTL_POWER_SEL	0x6C /* IO Power Mode Select controller */
>  
> +void k210_clk_early_init(void __iomem *regs);
> +
>  #endif
> 


-- 
Damien Le Moal
Western Digital Research



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