clk: Add K210 clock support

Due to the large number of clocks, I decided to use the CCF. The overall
structure is modeled after the imx code. Clocks parameters are stored in
several arrays, and are then instantiated at run-time. There are some
translation macros (FOOIFY()) which allow for more dense packing.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
CC: Lukasz Majewski <lukma@denx.de>

8 files changed, 837 insertions, 2 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index 0623da0..9d2d3a7 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -874,6 +874,13 @@ F:	arch/riscv/
 F:	cmd/riscv/
 F:	tools/prelink-riscv.c
 
+RISC-V KENDRYTE
+M:	Sean Anderson <seanga2@gmail.com>
+S:	Maintained
+F:	doc/device-tree-bindings/mfd/kendryte,k210-sysctl.txt
+F:	drivers/clk/kendryte/
+F:	include/kendryte/
+
 RNG
 M:	Sughosh Ganu <sughosh.ganu@linaro.org>
 R:	Heinrich Schuchardt <xypron.glpk@gmx.de>
diff --git a/doc/device-tree-bindings/mfd/kendryte,k210-sysctl.txt b/doc/device-tree-bindings/mfd/kendryte,k210-sysctl.txt
new file mode 100644
index 0000000..5b24abc
--- /dev/null
+++ b/doc/device-tree-bindings/mfd/kendryte,k210-sysctl.txt
@@ -0,0 +1,33 @@
+Kendryte K210 Sysctl
+
+This binding describes the K210 sysctl device, which contains many miscellaneous
+registers controlling system functionality. This node is a register map and can
+be reference by other bindings which need a phandle to the K210 sysctl regmap.
+
+Required properties:
+- compatible: should be
+	"kendryte,k210-sysctl", "syscon", "simple-mfd"
+- reg: address and length of the sysctl registers
+- reg-io-width: must be <4>
+
+Clock sub-node
+
+This node is a binding for the clock tree driver
+
+Required properties:
+- compatible: should be "kendryte,k210-clk"
+- clocks: phandle to the "in0" external oscillator
+- #clock-cells: must be <1>
+
+Example:
+sysctl: syscon@50440000 {
+	compatible = "kendryte,k210-sysctl", "syscon", "simple-mfd";
+	reg = <0x50440000 0x100>;
+	reg-io-width = <4>;
+
+	sysclk: clock-controller {
+		compatible = "kendryte,k210-clk";
+		clocks = <&in0>;
+		#clock-cells = <1>;
+	};
+};
diff --git a/drivers/clk/kendryte/Kconfig b/drivers/clk/kendryte/Kconfig
index 7b69c8a..073fca0 100644
--- a/drivers/clk/kendryte/Kconfig
+++ b/drivers/clk/kendryte/Kconfig
@@ -1,6 +1,6 @@
 config CLK_K210
 	bool "Clock support for Kendryte K210"
-	depends on CLK && CLK_CCF
+	depends on CLK && CLK_CCF && CLK_COMPOSITE_CCF
 	help
 	  This enables support clock driver for Kendryte K210 platforms.
 
diff --git a/drivers/clk/kendryte/Makefile b/drivers/clk/kendryte/Makefile
index 47f682f..6fb6825 100644
--- a/drivers/clk/kendryte/Makefile
+++ b/drivers/clk/kendryte/Makefile
@@ -1 +1 @@
-obj-y += bypass.o pll.o
+obj-y += bypass.o clk.o pll.o
diff --git a/drivers/clk/kendryte/clk.c b/drivers/clk/kendryte/clk.c
new file mode 100644
index 0000000..981b3b7
--- /dev/null
+++ b/drivers/clk/kendryte/clk.c
@@ -0,0 +1,663 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2019-20 Sean Anderson <seanga2@gmail.com>
+ */
+#include <kendryte/clk.h>
+
+#include <asm/io.h>
+#include <dt-bindings/clock/k210-sysctl.h>
+#include <dt-bindings/mfd/k210-sysctl.h>
+#include <dm.h>
+#include <log.h>
+#include <mapmem.h>
+
+#include <kendryte/bypass.h>
+#include <kendryte/pll.h>
+
+/* All methods are delegated to CCF clocks */
+
+static ulong k210_clk_get_rate(struct clk *clk)
+{
+	struct clk *c;
+	int err = clk_get_by_id(clk->id, &c);
+
+	if (err)
+		return err;
+	return clk_get_rate(c);
+}
+
+static ulong k210_clk_set_rate(struct clk *clk, unsigned long rate)
+{
+	struct clk *c;
+	int err = clk_get_by_id(clk->id, &c);
+
+	if (err)
+		return err;
+	return clk_set_rate(c, rate);
+}
+
+static int k210_clk_set_parent(struct clk *clk, struct clk *parent)
+{
+	struct clk *c, *p;
+	int err = clk_get_by_id(clk->id, &c);
+
+	if (err)
+		return err;
+
+	err = clk_get_by_id(parent->id, &p);
+	if (err)
+		return err;
+
+	return clk_set_parent(c, p);
+}
+
+static int k210_clk_endisable(struct clk *clk, bool enable)
+{
+	struct clk *c;
+	int err = clk_get_by_id(clk->id, &c);
+
+	if (err)
+		return err;
+	return enable ? clk_enable(c) : clk_disable(c);
+}
+
+static int k210_clk_enable(struct clk *clk)
+{
+	return k210_clk_endisable(clk, true);
+}
+
+static int k210_clk_disable(struct clk *clk)
+{
+	return k210_clk_endisable(clk, false);
+}
+
+static const struct clk_ops k210_clk_ops = {
+	.set_rate = k210_clk_set_rate,
+	.get_rate = k210_clk_get_rate,
+	.set_parent = k210_clk_set_parent,
+	.enable = k210_clk_enable,
+	.disable = k210_clk_disable,
+};
+
+/* Parents for muxed clocks */
+static const char * const generic_sels[] = { "in0_half", "pll0_half" };
+/* The first clock is in0, which is filled in by k210_clk_probe */
+static const char *aclk_sels[] = { NULL, "pll0_half" };
+static const char *pll2_sels[] = { NULL, "pll0", "pll1" };
+
+/*
+ * All parameters for different sub-clocks are collected into parameter arrays.
+ * These parameters are then initialized by the clock which uses them during
+ * probe. To save space, ids are automatically generated for each sub-clock by
+ * using an enum. Instead of storing a parameter struct for each clock, even for
+ * those clocks which don't use a particular type of sub-clock, we can just
+ * store the parameters for the clocks which need them.
+ *
+ * So why do it like this? Arranging all the sub-clocks together makes it very
+ * easy to find bugs in the code.
+ */
+
+#define DIV(id, off, shift, width) DIV_FLAGS(id, off, shift, width, 0)
+#define DIV_LIST \
+	DIV_FLAGS(K210_CLK_ACLK, K210_SYSCTL_SEL0, 1, 2, \
+		  CLK_DIVIDER_POWER_OF_TWO) \
+	DIV(K210_CLK_APB0,   K210_SYSCTL_SEL0,  3,  3) \
+	DIV(K210_CLK_APB1,   K210_SYSCTL_SEL0,  6,  3) \
+	DIV(K210_CLK_APB2,   K210_SYSCTL_SEL0,  9,  3) \
+	DIV(K210_CLK_SRAM0,  K210_SYSCTL_THR0,  0,  4) \
+	DIV(K210_CLK_SRAM1,  K210_SYSCTL_THR0,  4,  4) \
+	DIV(K210_CLK_AI,     K210_SYSCTL_THR0,  8,  4) \
+	DIV(K210_CLK_DVP,    K210_SYSCTL_THR0, 12,  4) \
+	DIV(K210_CLK_ROM,    K210_SYSCTL_THR0, 16,  4) \
+	DIV(K210_CLK_SPI0,   K210_SYSCTL_THR1,  0,  8) \
+	DIV(K210_CLK_SPI1,   K210_SYSCTL_THR1,  8,  8) \
+	DIV(K210_CLK_SPI2,   K210_SYSCTL_THR1, 16,  8) \
+	DIV(K210_CLK_SPI3,   K210_SYSCTL_THR1, 24,  8) \
+	DIV(K210_CLK_TIMER0, K210_SYSCTL_THR2,  0,  8) \
+	DIV(K210_CLK_TIMER1, K210_SYSCTL_THR2,  8,  8) \
+	DIV(K210_CLK_TIMER2, K210_SYSCTL_THR2, 16,  8) \
+	DIV(K210_CLK_I2S0,   K210_SYSCTL_THR3,  0, 16) \
+	DIV(K210_CLK_I2S1,   K210_SYSCTL_THR3, 16, 16) \
+	DIV(K210_CLK_I2S2,   K210_SYSCTL_THR4,  0, 16) \
+	DIV(K210_CLK_I2S0_M, K210_SYSCTL_THR4, 16,  8) \
+	DIV(K210_CLK_I2S1_M, K210_SYSCTL_THR4, 24,  8) \
+	DIV(K210_CLK_I2S2_M, K210_SYSCTL_THR4,  0,  8) \
+	DIV(K210_CLK_I2C0,   K210_SYSCTL_THR5,  8,  8) \
+	DIV(K210_CLK_I2C1,   K210_SYSCTL_THR5, 16,  8) \
+	DIV(K210_CLK_I2C2,   K210_SYSCTL_THR5, 24,  8) \
+	DIV(K210_CLK_WDT0,   K210_SYSCTL_THR6,  0,  8) \
+	DIV(K210_CLK_WDT1,   K210_SYSCTL_THR6,  8,  8)
+
+#define _DIVIFY(id) K210_CLK_DIV_##id
+#define DIVIFY(id) _DIVIFY(id)
+
+enum k210_div_ids {
+#define DIV_FLAGS(id, ...) DIVIFY(id),
+	DIV_LIST
+#undef DIV_FLAGS
+};
+
+struct k210_div_params {
+	u8 off;
+	u8 shift;
+	u8 width;
+	u8 flags;
+};
+
+static const struct k210_div_params k210_divs[] = {
+#define DIV_FLAGS(id, _off, _shift, _width, _flags) \
+	[DIVIFY(id)] = { \
+		.off = (_off), \
+		.shift = (_shift), \
+		.width = (_width), \
+		.flags = (_flags), \
+	},
+	DIV_LIST
+#undef DIV_FLAGS
+};
+
+#undef DIV
+#undef DIV_LIST
+
+#define GATE_LIST \
+	GATE(K210_CLK_CPU,    K210_SYSCTL_EN_CENT,  0) \
+	GATE(K210_CLK_SRAM0,  K210_SYSCTL_EN_CENT,  1) \
+	GATE(K210_CLK_SRAM1,  K210_SYSCTL_EN_CENT,  2) \
+	GATE(K210_CLK_APB0,   K210_SYSCTL_EN_CENT,  3) \
+	GATE(K210_CLK_APB1,   K210_SYSCTL_EN_CENT,  4) \
+	GATE(K210_CLK_APB2,   K210_SYSCTL_EN_CENT,  5) \
+	GATE(K210_CLK_ROM,    K210_SYSCTL_EN_PERI,  0) \
+	GATE(K210_CLK_DMA,    K210_SYSCTL_EN_PERI,  1) \
+	GATE(K210_CLK_AI,     K210_SYSCTL_EN_PERI,  2) \
+	GATE(K210_CLK_DVP,    K210_SYSCTL_EN_PERI,  3) \
+	GATE(K210_CLK_FFT,    K210_SYSCTL_EN_PERI,  4) \
+	GATE(K210_CLK_GPIO,   K210_SYSCTL_EN_PERI,  5) \
+	GATE(K210_CLK_SPI0,   K210_SYSCTL_EN_PERI,  6) \
+	GATE(K210_CLK_SPI1,   K210_SYSCTL_EN_PERI,  7) \
+	GATE(K210_CLK_SPI2,   K210_SYSCTL_EN_PERI,  8) \
+	GATE(K210_CLK_SPI3,   K210_SYSCTL_EN_PERI,  9) \
+	GATE(K210_CLK_I2S0,   K210_SYSCTL_EN_PERI, 10) \
+	GATE(K210_CLK_I2S1,   K210_SYSCTL_EN_PERI, 11) \
+	GATE(K210_CLK_I2S2,   K210_SYSCTL_EN_PERI, 12) \
+	GATE(K210_CLK_I2C0,   K210_SYSCTL_EN_PERI, 13) \
+	GATE(K210_CLK_I2C1,   K210_SYSCTL_EN_PERI, 14) \
+	GATE(K210_CLK_I2C2,   K210_SYSCTL_EN_PERI, 15) \
+	GATE(K210_CLK_UART1,  K210_SYSCTL_EN_PERI, 16) \
+	GATE(K210_CLK_UART2,  K210_SYSCTL_EN_PERI, 17) \
+	GATE(K210_CLK_UART3,  K210_SYSCTL_EN_PERI, 18) \
+	GATE(K210_CLK_AES,    K210_SYSCTL_EN_PERI, 19) \
+	GATE(K210_CLK_FPIOA,  K210_SYSCTL_EN_PERI, 20) \
+	GATE(K210_CLK_TIMER0, K210_SYSCTL_EN_PERI, 21) \
+	GATE(K210_CLK_TIMER1, K210_SYSCTL_EN_PERI, 22) \
+	GATE(K210_CLK_TIMER2, K210_SYSCTL_EN_PERI, 23) \
+	GATE(K210_CLK_WDT0,   K210_SYSCTL_EN_PERI, 24) \
+	GATE(K210_CLK_WDT1,   K210_SYSCTL_EN_PERI, 25) \
+	GATE(K210_CLK_SHA,    K210_SYSCTL_EN_PERI, 26) \
+	GATE(K210_CLK_OTP,    K210_SYSCTL_EN_PERI, 27) \
+	GATE(K210_CLK_RTC,    K210_SYSCTL_EN_PERI, 29)
+
+#define _GATEIFY(id) K210_CLK_GATE_##id
+#define GATEIFY(id) _GATEIFY(id)
+
+enum k210_gate_ids {
+#define GATE(id, ...) GATEIFY(id),
+	GATE_LIST
+#undef GATE
+};
+
+struct k210_gate_params {
+	u8 off;
+	u8 bit_idx;
+};
+
+static const struct k210_gate_params k210_gates[] = {
+#define GATE(id, _off, _idx) \
+	[GATEIFY(id)] = { \
+		.off = (_off), \
+		.bit_idx = (_idx), \
+	},
+	GATE_LIST
+#undef GATE
+};
+
+#undef GATE_LIST
+
+#define MUX(id, reg, shift, width) \
+	MUX_PARENTS(id, generic_sels, reg, shift, width)
+#define MUX_LIST \
+	MUX_PARENTS(K210_CLK_PLL2, pll2_sels, K210_SYSCTL_PLL2, 26, 2) \
+	MUX_PARENTS(K210_CLK_ACLK, aclk_sels, K210_SYSCTL_SEL0,  0, 1) \
+	MUX(K210_CLK_SPI3,   K210_SYSCTL_SEL0, 12, 1) \
+	MUX(K210_CLK_TIMER0, K210_SYSCTL_SEL0, 13, 1) \
+	MUX(K210_CLK_TIMER1, K210_SYSCTL_SEL0, 14, 1) \
+	MUX(K210_CLK_TIMER2, K210_SYSCTL_SEL0, 15, 1)
+
+#define _MUXIFY(id) K210_CLK_MUX_##id
+#define MUXIFY(id) _MUXIFY(id)
+
+enum k210_mux_ids {
+#define MUX_PARENTS(id, ...) MUXIFY(id),
+	MUX_LIST
+#undef MUX_PARENTS
+	K210_CLK_MUX_NONE,
+};
+
+struct k210_mux_params {
+	const char *const *parent_names;
+	u8 num_parents;
+	u8 off;
+	u8 shift;
+	u8 width;
+};
+
+static const struct k210_mux_params k210_muxes[] = {
+#define MUX_PARENTS(id, parents, _off, _shift, _width) \
+	[MUXIFY(id)] = { \
+		.parent_names = (const char * const *)(parents), \
+		.num_parents = ARRAY_SIZE(parents), \
+		.off = (_off), \
+		.shift = (_shift), \
+		.width = (_width), \
+	},
+	MUX_LIST
+#undef MUX_PARENTS
+};
+
+#undef MUX
+#undef MUX_LIST
+
+struct k210_pll_params {
+	u8 off;
+	u8 lock_off;
+	u8 shift;
+	u8 width;
+};
+
+static const struct k210_pll_params k210_plls[] = {
+#define PLL(_off, _shift, _width) { \
+	.off = (_off), \
+	.lock_off = K210_SYSCTL_PLL_LOCK, \
+	.shift = (_shift), \
+	.width = (_width), \
+}
+	[0] = PLL(K210_SYSCTL_PLL0,  0, 2),
+	[1] = PLL(K210_SYSCTL_PLL1,  8, 1),
+	[2] = PLL(K210_SYSCTL_PLL2, 16, 1),
+#undef PLL
+};
+
+#define COMP(id) \
+	COMP_FULL(id, MUXIFY(id), DIVIFY(id), GATEIFY(id))
+#define COMP_NOMUX(id) \
+	COMP_FULL(id, K210_CLK_MUX_NONE, DIVIFY(id), GATEIFY(id))
+#define COMP_LIST \
+	COMP(K210_CLK_SPI3) \
+	COMP(K210_CLK_TIMER0) \
+	COMP(K210_CLK_TIMER1) \
+	COMP(K210_CLK_TIMER2) \
+	COMP_NOMUX(K210_CLK_SRAM0) \
+	COMP_NOMUX(K210_CLK_SRAM1) \
+	COMP_NOMUX(K210_CLK_ROM) \
+	COMP_NOMUX(K210_CLK_DVP) \
+	COMP_NOMUX(K210_CLK_APB0) \
+	COMP_NOMUX(K210_CLK_APB1) \
+	COMP_NOMUX(K210_CLK_APB2) \
+	COMP_NOMUX(K210_CLK_AI) \
+	COMP_NOMUX(K210_CLK_I2S0) \
+	COMP_NOMUX(K210_CLK_I2S1) \
+	COMP_NOMUX(K210_CLK_I2S2) \
+	COMP_NOMUX(K210_CLK_WDT0) \
+	COMP_NOMUX(K210_CLK_WDT1) \
+	COMP_NOMUX(K210_CLK_SPI0) \
+	COMP_NOMUX(K210_CLK_SPI1) \
+	COMP_NOMUX(K210_CLK_SPI2) \
+	COMP_NOMUX(K210_CLK_I2C0) \
+	COMP_NOMUX(K210_CLK_I2C1) \
+	COMP_NOMUX(K210_CLK_I2C2)
+
+#define _COMPIFY(id) K210_CLK_COMP_##id
+#define COMPIFY(id) _COMPIFY(id)
+
+enum k210_comp_ids {
+#define COMP_FULL(id, ...) COMPIFY(id),
+	COMP_LIST
+#undef COMP_FULL
+};
+
+struct k210_comp_params {
+	u8 mux;
+	u8 div;
+	u8 gate;
+};
+
+static const struct k210_comp_params k210_comps[] = {
+#define COMP_FULL(id, _mux, _div, _gate) \
+	[COMPIFY(id)] = { \
+		.mux = (_mux), \
+		.div = (_div), \
+		.gate = (_gate), \
+	},
+	COMP_LIST
+#undef COMP_FULL
+};
+
+#undef COMP
+#undef COMP_ID
+#undef COMP_NOMUX
+#undef COMP_NOMUX_ID
+#undef COMP_LIST
+
+static struct clk *k210_bypass_children = {
+	NULL,
+};
+
+/* Helper functions to create sub-clocks */
+static struct clk_mux *k210_create_mux(const struct k210_mux_params *params,
+				       void *base)
+{
+	struct clk_mux *mux = kzalloc(sizeof(*mux), GFP_KERNEL);
+
+	if (!mux)
+		return mux;
+
+	mux->reg = base + params->off;
+	mux->mask = BIT(params->width) - 1;
+	mux->shift = params->shift;
+	mux->parent_names = params->parent_names;
+	mux->num_parents = params->num_parents;
+
+	return mux;
+}
+
+static struct clk_divider *k210_create_div(const struct k210_div_params *params,
+					   void *base)
+{
+	struct clk_divider *div = kzalloc(sizeof(*div), GFP_KERNEL);
+
+	if (!div)
+		return div;
+
+	div->reg = base + params->off;
+	div->shift = params->shift;
+	div->width = params->width;
+	div->flags = params->flags;
+
+	return div;
+}
+
+static struct clk_gate *k210_create_gate(const struct k210_gate_params *params,
+					 void *base)
+{
+	struct clk_gate *gate = kzalloc(sizeof(*gate), GFP_KERNEL);
+
+	if (!gate)
+		return gate;
+
+	gate->reg = base + params->off;
+	gate->bit_idx = params->bit_idx;
+
+	return gate;
+}
+
+static struct k210_pll *k210_create_pll(const struct k210_pll_params *params,
+					void *base)
+{
+	struct k210_pll *pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+
+	if (!pll)
+		return pll;
+
+	pll->reg = base + params->off;
+	pll->lock = base + params->lock_off;
+	pll->shift = params->shift;
+	pll->width = params->width;
+
+	return pll;
+}
+
+/* Create all sub-clocks, and then register the composite clock */
+static struct clk *k210_register_comp(const struct k210_comp_params *params,
+				      void *base, const char *name,
+				      const char *parent)
+{
+	const char *const *parent_names;
+	int num_parents;
+	struct clk *comp;
+	const struct clk_ops *mux_ops;
+	struct clk_mux *mux;
+	struct clk_divider *div;
+	struct clk_gate *gate;
+
+	if (params->mux == K210_CLK_MUX_NONE) {
+		if (!parent)
+			return ERR_PTR(-EINVAL);
+
+		mux_ops = NULL;
+		mux = NULL;
+		parent_names = &parent;
+		num_parents = 1;
+	} else {
+		mux_ops = &clk_mux_ops;
+		mux = k210_create_mux(&k210_muxes[params->mux], base);
+		if (!mux)
+			return ERR_PTR(-ENOMEM);
+
+		parent_names = mux->parent_names;
+		num_parents = mux->num_parents;
+	}
+
+	div = k210_create_div(&k210_divs[params->div], base);
+	if (!div) {
+		comp = ERR_PTR(-ENOMEM);
+		goto cleanup_mux;
+	}
+
+	gate = k210_create_gate(&k210_gates[params->gate], base);
+	if (!gate) {
+		comp = ERR_PTR(-ENOMEM);
+		goto cleanup_div;
+	}
+
+	comp = clk_register_composite(NULL, name, parent_names, num_parents,
+				      &mux->clk, mux_ops,
+				      &div->clk, &clk_divider_ops,
+				      &gate->clk, &clk_gate_ops, 0);
+	if (IS_ERR(comp))
+		goto cleanup_gate;
+	return comp;
+
+cleanup_gate:
+	free(gate);
+cleanup_div:
+	free(div);
+cleanup_mux:
+	if (mux)
+		free(mux);
+	return comp;
+}
+
+static bool probed;
+
+static int k210_clk_probe(struct udevice *dev)
+{
+	int ret;
+	const char *in0;
+	struct clk *in0_clk, *bypass;
+	struct clk_mux *mux;
+	struct clk_divider *div;
+	struct k210_pll *pll;
+	void *base;
+
+	/*
+	 * Only one instance of this driver allowed. This prevents weird bugs
+	 * when the driver fails part-way through probing. Some clocks will
+	 * already have been registered, and re-probing will register them
+	 * again, creating a bunch of duplicates. Better error-handling/cleanup
+	 * could fix this, but it's Probably Not Worth It (TM).
+	 */
+	if (probed)
+		return -ENOTSUPP;
+
+	base = dev_read_addr_ptr(dev_get_parent(dev));
+	if (!base)
+		return -EINVAL;
+
+	in0_clk = kzalloc(sizeof(*in0_clk), GFP_KERNEL);
+	if (!in0_clk)
+		return -ENOMEM;
+
+	ret = clk_get_by_index(dev, 0, in0_clk);
+	if (ret)
+		return ret;
+	in0 = in0_clk->dev->name;
+
+	probed = true;
+
+	aclk_sels[0] = in0;
+	pll2_sels[0] = in0;
+
+	/*
+	 * All PLLs have a broken bypass, but pll0 has the CPU downstream, so we
+	 * need to manually reparent it whenever we configure pll0
+	 */
+	pll = k210_create_pll(&k210_plls[0], base);
+	if (pll) {
+		bypass = k210_register_bypass("pll0", in0, &pll->clk,
+					      &k210_pll_ops, in0_clk);
+		clk_dm(K210_CLK_PLL0, bypass);
+	} else {
+		return -ENOMEM;
+	}
+
+	{
+		const struct k210_pll_params *params = &k210_plls[1];
+
+		clk_dm(K210_CLK_PLL1,
+		       k210_register_pll("pll1", in0, base + params->off,
+					 base + params->lock_off, params->shift,
+					 params->width));
+	}
+
+	/* PLL2 is muxed, so set up a composite clock */
+	mux = k210_create_mux(&k210_muxes[MUXIFY(K210_CLK_PLL2)], base);
+	pll = k210_create_pll(&k210_plls[2], base);
+	if (!mux || !pll) {
+		free(mux);
+		free(pll);
+	} else {
+		clk_dm(K210_CLK_PLL2,
+		       clk_register_composite(NULL, "pll2", pll2_sels,
+					      ARRAY_SIZE(pll2_sels),
+					      &mux->clk, &clk_mux_ops,
+					      &pll->clk, &k210_pll_ops,
+					      &pll->clk, &k210_pll_ops, 0));
+	}
+
+	/* Half-frequency clocks for "even" dividers */
+	clk_dm(K210_CLK_IN0_H,  k210_clk_half("in0_half", in0));
+	clk_dm(K210_CLK_PLL0_H, k210_clk_half("pll0_half", "pll0"));
+	clk_dm(K210_CLK_PLL2_H, k210_clk_half("pll2_half", "pll2"));
+
+	/* ACLK has no gate */
+	mux = k210_create_mux(&k210_muxes[MUXIFY(K210_CLK_ACLK)], base);
+	div = k210_create_div(&k210_divs[DIVIFY(K210_CLK_ACLK)], base);
+	if (!mux || !div) {
+		free(mux);
+		free(div);
+	} else {
+		struct clk *aclk =
+			clk_register_composite(NULL, "aclk", aclk_sels,
+					       ARRAY_SIZE(aclk_sels),
+					       &mux->clk, &clk_mux_ops,
+					       &div->clk, &clk_divider_ops,
+					       NULL, NULL, 0);
+		clk_dm(K210_CLK_ACLK, aclk);
+		if (!IS_ERR(aclk)) {
+			k210_bypass_children = aclk;
+			k210_bypass_set_children(bypass,
+						 &k210_bypass_children, 1);
+		}
+	}
+
+#define REGISTER_COMP(id, name) \
+	clk_dm(id, \
+	       k210_register_comp(&k210_comps[COMPIFY(id)], base, name, NULL))
+	REGISTER_COMP(K210_CLK_SPI3,   "spi3");
+	REGISTER_COMP(K210_CLK_TIMER0, "timer0");
+	REGISTER_COMP(K210_CLK_TIMER1, "timer1");
+	REGISTER_COMP(K210_CLK_TIMER2, "timer2");
+#undef REGISTER_COMP
+
+	/* Dividing clocks, no mux */
+#define REGISTER_COMP_NOMUX(id, name, parent) \
+	clk_dm(id, \
+	       k210_register_comp(&k210_comps[COMPIFY(id)], base, name, parent))
+	REGISTER_COMP_NOMUX(K210_CLK_SRAM0, "sram0", "aclk");
+	REGISTER_COMP_NOMUX(K210_CLK_SRAM1, "sram1", "aclk");
+	REGISTER_COMP_NOMUX(K210_CLK_ROM,   "rom",   "aclk");
+	REGISTER_COMP_NOMUX(K210_CLK_DVP,   "dvp",   "aclk");
+	REGISTER_COMP_NOMUX(K210_CLK_APB0,  "apb0",  "aclk");
+	REGISTER_COMP_NOMUX(K210_CLK_APB1,  "apb1",  "aclk");
+	REGISTER_COMP_NOMUX(K210_CLK_APB2,  "apb2",  "aclk");
+	REGISTER_COMP_NOMUX(K210_CLK_AI,    "ai",    "pll1");
+	REGISTER_COMP_NOMUX(K210_CLK_I2S0,  "i2s0",  "pll2_half");
+	REGISTER_COMP_NOMUX(K210_CLK_I2S1,  "i2s1",  "pll2_half");
+	REGISTER_COMP_NOMUX(K210_CLK_I2S2,  "i2s2",  "pll2_half");
+	REGISTER_COMP_NOMUX(K210_CLK_WDT0,  "wdt0",  "in0_half");
+	REGISTER_COMP_NOMUX(K210_CLK_WDT1,  "wdt1",  "in0_half");
+	REGISTER_COMP_NOMUX(K210_CLK_SPI0,  "spi0",  "pll0_half");
+	REGISTER_COMP_NOMUX(K210_CLK_SPI1,  "spi1",  "pll0_half");
+	REGISTER_COMP_NOMUX(K210_CLK_SPI2,  "spi2",  "pll0_half");
+	REGISTER_COMP_NOMUX(K210_CLK_I2C0,  "i2c0",  "pll0_half");
+	REGISTER_COMP_NOMUX(K210_CLK_I2C1,  "i2c1",  "pll0_half");
+	REGISTER_COMP_NOMUX(K210_CLK_I2C2,  "i2c2",  "pll0_half");
+#undef REGISTER_COMP_NOMUX
+
+	/* Dividing clocks */
+#define REGISTER_DIV(id, name, parent) do {\
+	const struct k210_div_params *params = &k210_divs[DIVIFY(id)]; \
+	clk_dm(id, \
+	       clk_register_divider(NULL, name, parent, 0, base + params->off, \
+				    params->shift, params->width, 0)); \
+} while (false)
+	REGISTER_DIV(K210_CLK_I2S0_M, "i2s0_m", "pll2_half");
+	REGISTER_DIV(K210_CLK_I2S1_M, "i2s1_m", "pll2_half");
+	REGISTER_DIV(K210_CLK_I2S2_M, "i2s2_m", "pll2_half");
+#undef REGISTER_DIV
+
+	/* Gated clocks */
+#define REGISTER_GATE(id, name, parent) do { \
+	const struct k210_gate_params *params = &k210_gates[GATEIFY(id)]; \
+	clk_dm(id, \
+	       clk_register_gate(NULL, name, parent, 0, base + params->off, \
+				 params->bit_idx, 0, NULL)); \
+} while (false)
+	REGISTER_GATE(K210_CLK_CPU,   "cpu",   "aclk");
+	REGISTER_GATE(K210_CLK_DMA,   "dma",   "aclk");
+	REGISTER_GATE(K210_CLK_FFT,   "fft",   "aclk");
+	REGISTER_GATE(K210_CLK_GPIO,  "gpio",  "apb0");
+	REGISTER_GATE(K210_CLK_UART1, "uart1", "apb0");
+	REGISTER_GATE(K210_CLK_UART2, "uart2", "apb0");
+	REGISTER_GATE(K210_CLK_UART3, "uart3", "apb0");
+	REGISTER_GATE(K210_CLK_FPIOA, "fpioa", "apb0");
+	REGISTER_GATE(K210_CLK_SHA,   "sha",   "apb0");
+	REGISTER_GATE(K210_CLK_AES,   "aes",   "apb1");
+	REGISTER_GATE(K210_CLK_OTP,   "otp",   "apb1");
+	REGISTER_GATE(K210_CLK_RTC,   "rtc",   in0);
+#undef REGISTER_GATE
+
+	return 0;
+}
+
+static const struct udevice_id k210_clk_ids[] = {
+	{ .compatible = "kendryte,k210-clk" },
+	{ },
+};
+
+U_BOOT_DRIVER(k210_clk) = {
+	.name = "k210_clk",
+	.id = UCLASS_CLK,
+	.of_match = k210_clk_ids,
+	.ops = &k210_clk_ops,
+	.probe = k210_clk_probe,
+};
diff --git a/include/dt-bindings/clock/k210-sysctl.h b/include/dt-bindings/clock/k210-sysctl.h
new file mode 100644
index 0000000..0e3ed3f
--- /dev/null
+++ b/include/dt-bindings/clock/k210-sysctl.h
@@ -0,0 +1,59 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2019-20 Sean Anderson <seanga2@gmail.com>
+ */
+
+#ifndef CLOCK_K210_SYSCTL_H
+#define CLOCK_K210_SYSCTL_H
+
+/*
+ * Arbitrary identifiers for clocks.
+ */
+#define K210_CLK_NONE   0
+#define K210_CLK_IN0_H  1
+#define K210_CLK_PLL0_H 2
+#define K210_CLK_PLL0   3
+#define K210_CLK_PLL1   4
+#define K210_CLK_PLL2   5
+#define K210_CLK_PLL2_H 6
+#define K210_CLK_CPU    7
+#define K210_CLK_SRAM0  8
+#define K210_CLK_SRAM1  9
+#define K210_CLK_APB0   10
+#define K210_CLK_APB1   11
+#define K210_CLK_APB2   12
+#define K210_CLK_ROM    13
+#define K210_CLK_DMA    14
+#define K210_CLK_AI     15
+#define K210_CLK_DVP    16
+#define K210_CLK_FFT    17
+#define K210_CLK_GPIO   18
+#define K210_CLK_SPI0   19
+#define K210_CLK_SPI1   20
+#define K210_CLK_SPI2   21
+#define K210_CLK_SPI3   22
+#define K210_CLK_I2S0   23
+#define K210_CLK_I2S1   24
+#define K210_CLK_I2S2   25
+#define K210_CLK_I2S0_M 26
+#define K210_CLK_I2S1_M 27
+#define K210_CLK_I2S2_M 28
+#define K210_CLK_I2C0   29
+#define K210_CLK_I2C1   30
+#define K210_CLK_I2C2   31
+#define K210_CLK_UART1  32
+#define K210_CLK_UART2  33
+#define K210_CLK_UART3  34
+#define K210_CLK_AES    35
+#define K210_CLK_FPIOA  36
+#define K210_CLK_TIMER0 37
+#define K210_CLK_TIMER1 38
+#define K210_CLK_TIMER2 39
+#define K210_CLK_WDT0   40
+#define K210_CLK_WDT1   41
+#define K210_CLK_SHA    42
+#define K210_CLK_OTP    43
+#define K210_CLK_RTC    44
+#define K210_CLK_ACLK   45
+
+#endif /* CLOCK_K210_SYSCTL_H */
diff --git a/include/dt-bindings/mfd/k210-sysctl.h b/include/dt-bindings/mfd/k210-sysctl.h
new file mode 100644
index 0000000..bfc918d
--- /dev/null
+++ b/include/dt-bindings/mfd/k210-sysctl.h
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2020 Sean Anderson <seanga2@gmail.com>
+ */
+
+#ifndef K210_SYSCTL_H
+#define K210_SYSCTL_H
+
+/* Taken from kendryte-standalone-sdk/lib/drivers/include/sysctl.h */
+#define K210_SYSCTL_GIT_ID     0x00 /* Git short commit id */
+#define K210_SYSCTL_UART_BAUD  0x04 /* Default UARTHS baud rate */
+#define K210_SYSCTL_PLL0       0x08 /* PLL0 controller */
+#define K210_SYSCTL_PLL1       0x0C /* PLL1 controller */
+#define K210_SYSCTL_PLL2       0x10 /* PLL2 controller */
+#define K210_SYSCTL_PLL_LOCK   0x18 /* PLL lock tester */
+#define K210_SYSCTL_ROM_ERROR  0x1C /* AXI ROM detector */
+#define K210_SYSCTL_SEL0       0x20 /* Clock select controller 0 */
+#define K210_SYSCTL_SEL1       0x24 /* Clock select controller 1 */
+#define K210_SYSCTL_EN_CENT    0x28 /* Central clock enable */
+#define K210_SYSCTL_EN_PERI    0x2C /* Peripheral clock enable */
+#define K210_SYSCTL_SOFT_RESET 0x30 /* Soft reset ctrl */
+#define K210_SYSCTL_PERI_RESET 0x34 /* Peripheral reset controller */
+#define K210_SYSCTL_THR0       0x38 /* Clock threshold controller 0 */
+#define K210_SYSCTL_THR1       0x3C /* Clock threshold controller 1 */
+#define K210_SYSCTL_THR2       0x40 /* Clock threshold controller 2 */
+#define K210_SYSCTL_THR3       0x44 /* Clock threshold controller 3 */
+#define K210_SYSCTL_THR4       0x48 /* Clock threshold controller 4 */
+#define K210_SYSCTL_THR5       0x4C /* Clock threshold controller 5 */
+#define K210_SYSCTL_THR6       0x50 /* Clock threshold controller 6 */
+#define K210_SYSCTL_MISC       0x54 /* Miscellaneous controller */
+#define K210_SYSCTL_PERI       0x58 /* Peripheral controller */
+#define K210_SYSCTL_SPI_SLEEP  0x5C /* SPI sleep controller */
+#define K210_SYSCTL_RESET_STAT 0x60 /* Reset source status */
+#define K210_SYSCTL_DMA_SEL0   0x64 /* DMA handshake selector 0 */
+#define K210_SYSCTL_DMA_SEL1   0x68 /* DMA handshake selector 1 */
+#define K210_SYSCTL_POWER_SEL  0x6C /* IO Power Mode Select controller */
+
+#endif /* K210_SYSCTL_H */
diff --git a/include/kendryte/clk.h b/include/kendryte/clk.h
new file mode 100644
index 0000000..9c6245d
--- /dev/null
+++ b/include/kendryte/clk.h
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2019-20 Sean Anderson <seanga2@gmail.com>
+ */
+
+#ifndef K210_CLK_H
+#define K210_CLK_H
+
+#define LOG_CATEGORY UCLASS_CLK
+#include <linux/types.h>
+#include <linux/clk-provider.h>
+
+static inline struct clk *k210_clk_gate(const char *name,
+					const char *parent_name,
+					void __iomem *reg, u8 bit_idx)
+{
+	return clk_register_gate(NULL, name, parent_name, 0, reg, bit_idx, 0,
+				 NULL);
+}
+
+static inline struct clk *k210_clk_half(const char *name,
+					const char *parent_name)
+{
+	return clk_register_fixed_factor(NULL, name, parent_name, 0, 1, 2);
+}
+
+static inline struct clk *k210_clk_div(const char *name,
+				       const char *parent_name,
+				       void __iomem *reg, u8 shift, u8 width)
+{
+	return clk_register_divider(NULL, name, parent_name, 0, reg, shift,
+				    width, 0);
+}
+
+#endif /* K210_CLK_H */