ARC: clk: introduce HSDK CGU clock driver

Synopsys HSDK clock controller generates and supplies clocks to various controllers and peripherals within the SoC. Each clock has assigned identifier and client device tree nodes can use this identifier to specify the clock which they consume. All available clocks are defined as preprocessor macros in the dt-bindings/clock/snps,hsdk-cgu.h header and can be used in device tree sources. Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
2024-11-24 21:54:01 +00:00 · 2017-12-10 21:20:08 +03:00 · 2017-12-10 21:20:08 +03:00 · e80dac0ab8
commit e80dac0ab8
parent 3cf239394a
6 changed files with 654 additions and 0 deletions
--- a/8
+++ b/8
@ -65,6 +65,14 @@ S:	Maintained
 L:	uboot-snps-arc@synopsys.com
 F:	drivers/gpio/hsdk-creg-gpio.c

+ARC HSDK CGU CLOCK
+M:	Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
+S:	Maintained
+L:	uboot-snps-arc@synopsys.com
+F:	drivers/clk/clk-hsdk-cgu.c
+F:	include/dt-bindings/clock/snps,hsdk-cgu.h
+F:	doc/device-tree-bindings/clock/snps,hsdk-cgu.txt
+
 ARM
 M:	Albert Aribaud <albert.u.boot@aribaud.net>
 S:	Maintained
--- a/doc/device-tree-bindings/clock/snps,hsdk-cgu.txt
+++ b/doc/device-tree-bindings/clock/snps,hsdk-cgu.txt
@ -0,0 +1,35 @@
+* Synopsys HSDK clock generation unit
+
+The Synopsys HSDK clock controller generates and supplies clock to various
+controllers and peripherals within the SoC.
+
+Required Properties:
+
+- compatible: should be "snps,hsdk-cgu-clock"
+- reg: the pair of physical base address and length of clock generation unit
+  memory mapped region and creg arc core divider memory mapped region.
+- #clock-cells: should be 1.
+
+Each clock is assigned an identifier and client nodes can use this identifier
+to specify the clock which they consume. All available clocks are defined as
+preprocessor macros in the dt-bindings/clock/snps,hsdk-cgu.h headers and can be
+used in device tree sources.
+
+Example: Clock controller node:
+
+	cgu_clk: cgu-clk@f0000000 {
+		compatible = "snps,hsdk-cgu-clock";
+		reg = <0xf0000000 0x1000>, <0xf00014B8 0x4>;
+		#clock-cells = <1>;
+	};
+
+Example: UART controller node that consumes the clock generated by the clock
+controller:
+
+	uart0: serial0@f0005000 {
+		compatible = "snps,dw-apb-uart";
+		reg = <0xf0005000 0x1000>;
+		reg-shift = <2>;
+		reg-io-width = <4>;
+		clocks = <&cgu_clk CLK_SYS_UART_REF>;
+	};
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@ -54,6 +54,12 @@ config CLK_STM32F
 	  This clock driver adds support for RCC clock management
 	  for STM32F4 and STM32F7 SoCs.

+config CLK_HSDK
+	bool "Enable cgu clock driver for HSDK"
+	depends on CLK
+	help
+	  Enable this to support the cgu clocks on Synopsys ARC HSDK
+
 config CLK_ZYNQ
 	bool "Enable clock driver support for Zynq"
 	depends on CLK && ARCH_ZYNQ
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@ -20,6 +20,7 @@ obj-$(CONFIG_CLK_EXYNOS) += exynos/
 obj-$(CONFIG_CLK_AT91) += at91/
 obj-$(CONFIG_CLK_BCM6345) += clk_bcm6345.o
 obj-$(CONFIG_CLK_BOSTON) += clk_boston.o
+obj-$(CONFIG_CLK_HSDK) += clk-hsdk-cgu.o
 obj-$(CONFIG_ARCH_ASPEED) += aspeed/
 obj-$(CONFIG_CLK_STM32F) += clk_stm32f.o
 obj-$(CONFIG_STM32H7) += clk_stm32h7.o
--- a/drivers/clk/clk-hsdk-cgu.c
+++ b/drivers/clk/clk-hsdk-cgu.c
@ -0,0 +1,564 @@
+/*
+ * Synopsys HSDK SDP CGU clock driver
+ *
+ * Copyright (C) 2017 Synopsys
+ * Author: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <common.h>
+#include <clk-uclass.h>
+#include <div64.h>
+#include <dm.h>
+#include <linux/io.h>
+
+/*
+ * Synopsys ARC HSDK clock tree.
+ *
+ *   ------------------
+ *   | 33.33 MHz xtal |
+ *   ------------------
+ *            |
+ *            |   -----------
+ *            |-->| ARC PLL |
+ *            |   -----------
+ *            |        |
+ *            |        |-->|CGU_ARC_IDIV|----------->
+ *            |        |-->|CREG_CORE_IF_DIV|------->
+ *            |
+ *            |   --------------
+ *            |-->| SYSTEM PLL |
+ *            |   --------------
+ *            |        |
+ *            |        |-->|CGU_SYS_IDIV_APB|------->
+ *            |        |-->|CGU_SYS_IDIV_AXI|------->
+ *            |        |-->|CGU_SYS_IDIV_*|--------->
+ *            |        |-->|CGU_SYS_IDIV_EBI_REF|--->
+ *            |
+ *            |   --------------
+ *            |-->| TUNNEL PLL |
+ *            |   --------------
+ *            |        |
+ *            |        |-->|CGU_TUN_IDIV|----------->
+ *            |
+ *            |   ------------
+ *            |-->| HDMI PLL |
+ *            |   ------------
+ *            |        |
+ *            |        |-->|CGU_HDMI_IDIV_APB|------>
+ *            |
+ *            |   -----------
+ *            |-->| DDR PLL |
+ *                -----------
+ *                     |
+ *                     |---------------------------->
+ */
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define CGU_ARC_IDIV		0x080
+#define CGU_TUN_IDIV		0x380
+#define CGU_HDMI_IDIV_APB	0x480
+#define CGU_SYS_IDIV_APB	0x180
+#define CGU_SYS_IDIV_AXI	0x190
+#define CGU_SYS_IDIV_ETH	0x1A0
+#define CGU_SYS_IDIV_USB	0x1B0
+#define CGU_SYS_IDIV_SDIO	0x1C0
+#define CGU_SYS_IDIV_HDMI	0x1D0
+#define CGU_SYS_IDIV_GFX_CORE	0x1E0
+#define CGU_SYS_IDIV_GFX_DMA	0x1F0
+#define CGU_SYS_IDIV_GFX_CFG	0x200
+#define CGU_SYS_IDIV_DMAC_CORE	0x210
+#define CGU_SYS_IDIV_DMAC_CFG	0x220
+#define CGU_SYS_IDIV_SDIO_REF	0x230
+#define CGU_SYS_IDIV_SPI_REF	0x240
+#define CGU_SYS_IDIV_I2C_REF	0x250
+#define CGU_SYS_IDIV_UART_REF	0x260
+#define CGU_SYS_IDIV_EBI_REF	0x270
+
+#define CGU_IDIV_MASK		0xFF /* All idiv have 8 significant bits */
+
+#define CGU_ARC_PLL		0x0
+#define CGU_SYS_PLL		0x10
+#define CGU_DDR_PLL		0x20
+#define CGU_TUN_PLL		0x30
+#define CGU_HDMI_PLL		0x40
+
+#define CGU_PLL_CTRL		0x000 /* ARC PLL control register */
+#define CGU_PLL_STATUS		0x004 /* ARC PLL status register */
+#define CGU_PLL_FMEAS		0x008 /* ARC PLL frequency measurement register */
+#define CGU_PLL_MON		0x00C /* ARC PLL monitor register */
+
+#define CGU_PLL_CTRL_ODIV_SHIFT		2
+#define CGU_PLL_CTRL_IDIV_SHIFT		4
+#define CGU_PLL_CTRL_FBDIV_SHIFT	9
+#define CGU_PLL_CTRL_BAND_SHIFT		20
+
+#define CGU_PLL_CTRL_ODIV_MASK		GENMASK(3, CGU_PLL_CTRL_ODIV_SHIFT)
+#define CGU_PLL_CTRL_IDIV_MASK		GENMASK(8, CGU_PLL_CTRL_IDIV_SHIFT)
+#define CGU_PLL_CTRL_FBDIV_MASK		GENMASK(15, CGU_PLL_CTRL_FBDIV_SHIFT)
+
+#define CGU_PLL_CTRL_PD			BIT(0)
+#define CGU_PLL_CTRL_BYPASS		BIT(1)
+
+#define CGU_PLL_STATUS_LOCK		BIT(0)
+#define CGU_PLL_STATUS_ERR		BIT(1)
+
+#define HSDK_PLL_MAX_LOCK_TIME		100 /* 100 us */
+
+#define CREG_CORE_IF_DIV		0x000 /* ARC CORE interface divider */
+#define CORE_IF_CLK_THRESHOLD_HZ	500000000
+#define CREG_CORE_IF_CLK_DIV_1		0x0
+#define CREG_CORE_IF_CLK_DIV_2		0x1
+
+#define PARENT_RATE			33333333 /* fixed clock - xtal */
+#define CGU_MAX_CLOCKS			24
+
+struct hsdk_pll_cfg {
+	u32 rate;
+	u32 idiv;
+	u32 fbdiv;
+	u32 odiv;
+	u32 band;
+};
+
+static const struct hsdk_pll_cfg asdt_pll_cfg[] = {
+	{ 100000000,  0, 11, 3, 0 },
+	{ 125000000,  0, 14, 3, 0 },
+	{ 133000000,  0, 15, 3, 0 },
+	{ 150000000,  0, 17, 3, 0 },
+	{ 200000000,  1, 47, 3, 0 },
+	{ 233000000,  1, 27, 2, 0 },
+	{ 300000000,  1, 35, 2, 0 },
+	{ 333000000,  1, 39, 2, 0 },
+	{ 400000000,  1, 47, 2, 0 },
+	{ 500000000,  0, 14, 1, 0 },
+	{ 600000000,  0, 17, 1, 0 },
+	{ 700000000,  0, 20, 1, 0 },
+	{ 800000000,  0, 23, 1, 0 },
+	{ 900000000,  1, 26, 0, 0 },
+	{ 1000000000, 1, 29, 0, 0 },
+	{ 1100000000, 1, 32, 0, 0 },
+	{ 1200000000, 1, 35, 0, 0 },
+	{ 1300000000, 1, 38, 0, 0 },
+	{ 1400000000, 1, 41, 0, 0 },
+	{ 1500000000, 1, 44, 0, 0 },
+	{ 1600000000, 1, 47, 0, 0 },
+	{}
+};
+
+static const struct hsdk_pll_cfg hdmi_pll_cfg[] = {
+	{ 297000000,  0, 21, 2, 0 },
+	{ 540000000,  0, 19, 1, 0 },
+	{ 594000000,  0, 21, 1, 0 },
+	{}
+};
+
+struct hsdk_cgu_clk {
+	/* CGU block register */
+	void __iomem *cgu_regs;
+	/* CREG block register */
+	void __iomem *creg_regs;
+
+	/* PLLs registers */
+	void __iomem *regs;
+	/* PLLs special registers */
+	void __iomem *spec_regs;
+	/* PLLs devdata */
+	const struct hsdk_pll_devdata *pll_devdata;
+
+	/* Dividers registers */
+	void __iomem *idiv_regs;
+};
+
+struct hsdk_pll_devdata {
+	const struct hsdk_pll_cfg *pll_cfg;
+	int (*update_rate)(struct hsdk_cgu_clk *clk, unsigned long rate,
+			   const struct hsdk_pll_cfg *cfg);
+};
+
+static int hsdk_pll_core_update_rate(struct hsdk_cgu_clk *, unsigned long,
+				     const struct hsdk_pll_cfg *);
+static int hsdk_pll_comm_update_rate(struct hsdk_cgu_clk *, unsigned long,
+				     const struct hsdk_pll_cfg *);
+
+static const struct hsdk_pll_devdata core_pll_dat = {
+	.pll_cfg = asdt_pll_cfg,
+	.update_rate = hsdk_pll_core_update_rate,
+};
+
+static const struct hsdk_pll_devdata sdt_pll_dat = {
+	.pll_cfg = asdt_pll_cfg,
+	.update_rate = hsdk_pll_comm_update_rate,
+};
+
+static const struct hsdk_pll_devdata hdmi_pll_dat = {
+	.pll_cfg = hdmi_pll_cfg,
+	.update_rate = hsdk_pll_comm_update_rate,
+};
+
+static ulong idiv_set(struct clk *, ulong);
+static ulong idiv_get(struct clk *);
+static int idiv_off(struct clk *);
+static ulong pll_set(struct clk *, ulong);
+static ulong pll_get(struct clk *);
+
+struct hsdk_cgu_clock_map {
+	u32 cgu_pll_oft;
+	u32 creg_div_oft;
+	u32 cgu_div_oft;
+	const struct hsdk_pll_devdata *pll_devdata;
+	ulong (*get_rate)(struct clk *clk);
+	ulong (*set_rate)(struct clk *clk, ulong rate);
+	int (*disable)(struct clk *clk);
+};
+
+static const struct hsdk_cgu_clock_map clock_map[] = {
+	{ CGU_ARC_PLL, 0, 0, &core_pll_dat, pll_get, pll_set, NULL },
+	{ CGU_ARC_PLL, 0, CGU_ARC_IDIV, &core_pll_dat, idiv_get, idiv_set, idiv_off },
+	{ CGU_DDR_PLL, 0, 0, &sdt_pll_dat, pll_get, pll_set, NULL },
+	{ CGU_SYS_PLL, 0, 0, &sdt_pll_dat, pll_get, pll_set, NULL },
+	{ CGU_SYS_PLL, 0, CGU_SYS_IDIV_APB, &sdt_pll_dat, idiv_get, idiv_set, idiv_off },
+	{ CGU_SYS_PLL, 0, CGU_SYS_IDIV_AXI, &sdt_pll_dat, idiv_get, idiv_set, idiv_off },
+	{ CGU_SYS_PLL, 0, CGU_SYS_IDIV_ETH, &sdt_pll_dat, idiv_get, idiv_set, idiv_off },
+	{ CGU_SYS_PLL, 0, CGU_SYS_IDIV_USB, &sdt_pll_dat, idiv_get, idiv_set, idiv_off },
+	{ CGU_SYS_PLL, 0, CGU_SYS_IDIV_SDIO, &sdt_pll_dat, idiv_get, idiv_set, idiv_off },
+	{ CGU_SYS_PLL, 0, CGU_SYS_IDIV_HDMI, &sdt_pll_dat, idiv_get, idiv_set, idiv_off },
+	{ CGU_SYS_PLL, 0, CGU_SYS_IDIV_GFX_CORE, &sdt_pll_dat, idiv_get, idiv_set, idiv_off },
+	{ CGU_SYS_PLL, 0, CGU_SYS_IDIV_GFX_DMA, &sdt_pll_dat, idiv_get, idiv_set, idiv_off },
+	{ CGU_SYS_PLL, 0, CGU_SYS_IDIV_GFX_CFG, &sdt_pll_dat, idiv_get, idiv_set, idiv_off },
+	{ CGU_SYS_PLL, 0, CGU_SYS_IDIV_DMAC_CORE, &sdt_pll_dat, idiv_get, idiv_set, idiv_off },
+	{ CGU_SYS_PLL, 0, CGU_SYS_IDIV_DMAC_CFG, &sdt_pll_dat, idiv_get, idiv_set, idiv_off },
+	{ CGU_SYS_PLL, 0, CGU_SYS_IDIV_SDIO_REF, &sdt_pll_dat, idiv_get, idiv_set, idiv_off },
+	{ CGU_SYS_PLL, 0, CGU_SYS_IDIV_SPI_REF, &sdt_pll_dat, idiv_get, idiv_set, idiv_off },
+	{ CGU_SYS_PLL, 0, CGU_SYS_IDIV_I2C_REF, &sdt_pll_dat, idiv_get, idiv_set, idiv_off },
+	{ CGU_SYS_PLL, 0, CGU_SYS_IDIV_UART_REF, &sdt_pll_dat, idiv_get, idiv_set, idiv_off },
+	{ CGU_SYS_PLL, 0, CGU_SYS_IDIV_EBI_REF, &sdt_pll_dat, idiv_get, idiv_set, idiv_off },
+	{ CGU_TUN_PLL, 0, 0, &sdt_pll_dat, pll_get, pll_set, NULL },
+	{ CGU_TUN_PLL, 0, CGU_TUN_IDIV, &sdt_pll_dat, idiv_get, idiv_set, idiv_off },
+	{ CGU_HDMI_PLL, 0, 0, &hdmi_pll_dat, pll_get, pll_set, NULL },
+	{ CGU_HDMI_PLL, 0, CGU_HDMI_IDIV_APB, &hdmi_pll_dat, idiv_get, idiv_set, idiv_off }
+};
+
+static inline void hsdk_idiv_write(struct hsdk_cgu_clk *clk, u32 val)
+{
+	iowrite32(val, clk->idiv_regs);
+}
+
+static inline u32 hsdk_idiv_read(struct hsdk_cgu_clk *clk)
+{
+	return ioread32(clk->idiv_regs);
+}
+
+static inline void hsdk_pll_write(struct hsdk_cgu_clk *clk, u32 reg, u32 val)
+{
+	iowrite32(val, clk->regs + reg);
+}
+
+static inline u32 hsdk_pll_read(struct hsdk_cgu_clk *clk, u32 reg)
+{
+	return ioread32(clk->regs + reg);
+}
+
+static inline void hsdk_pll_spcwrite(struct hsdk_cgu_clk *clk, u32 reg, u32 val)
+{
+	iowrite32(val, clk->spec_regs + reg);
+}
+
+static inline u32 hsdk_pll_spcread(struct hsdk_cgu_clk *clk, u32 reg)
+{
+	return ioread32(clk->spec_regs + reg);
+}
+
+static inline void hsdk_pll_set_cfg(struct hsdk_cgu_clk *clk,
+				    const struct hsdk_pll_cfg *cfg)
+{
+	u32 val = 0;
+
+	/* Powerdown and Bypass bits should be cleared */
+	val |= cfg->idiv << CGU_PLL_CTRL_IDIV_SHIFT;
+	val |= cfg->fbdiv << CGU_PLL_CTRL_FBDIV_SHIFT;
+	val |= cfg->odiv << CGU_PLL_CTRL_ODIV_SHIFT;
+	val |= cfg->band << CGU_PLL_CTRL_BAND_SHIFT;
+
+	pr_debug("write configurarion: %#x\n", val);
+
+	hsdk_pll_write(clk, CGU_PLL_CTRL, val);
+}
+
+static inline bool hsdk_pll_is_locked(struct hsdk_cgu_clk *clk)
+{
+	return !!(hsdk_pll_read(clk, CGU_PLL_STATUS) & CGU_PLL_STATUS_LOCK);
+}
+
+static inline bool hsdk_pll_is_err(struct hsdk_cgu_clk *clk)
+{
+	return !!(hsdk_pll_read(clk, CGU_PLL_STATUS) & CGU_PLL_STATUS_ERR);
+}
+
+static ulong pll_get(struct clk *sclk)
+{
+	u32 val;
+	u64 rate;
+	u32 idiv, fbdiv, odiv;
+	struct hsdk_cgu_clk *clk = dev_get_priv(sclk->dev);
+
+	val = hsdk_pll_read(clk, CGU_PLL_CTRL);
+
+	pr_debug("current configurarion: %#x\n", val);
+
+	/* Check if PLL is disabled */
+	if (val & CGU_PLL_CTRL_PD)
+		return 0;
+
+	/* Check if PLL is bypassed */
+	if (val & CGU_PLL_CTRL_BYPASS)
+		return PARENT_RATE;
+
+	/* input divider = reg.idiv + 1 */
+	idiv = 1 + ((val & CGU_PLL_CTRL_IDIV_MASK) >> CGU_PLL_CTRL_IDIV_SHIFT);
+	/* fb divider = 2*(reg.fbdiv + 1) */
+	fbdiv = 2 * (1 + ((val & CGU_PLL_CTRL_FBDIV_MASK) >> CGU_PLL_CTRL_FBDIV_SHIFT));
+	/* output divider = 2^(reg.odiv) */
+	odiv = 1 << ((val & CGU_PLL_CTRL_ODIV_MASK) >> CGU_PLL_CTRL_ODIV_SHIFT);
+
+	rate = (u64)PARENT_RATE * fbdiv;
+	do_div(rate, idiv * odiv);
+
+	return rate;
+}
+
+static unsigned long hsdk_pll_round_rate(struct clk *sclk, unsigned long rate)
+{
+	int i;
+	unsigned long best_rate;
+	struct hsdk_cgu_clk *clk = dev_get_priv(sclk->dev);
+	const struct hsdk_pll_cfg *pll_cfg = clk->pll_devdata->pll_cfg;
+
+	if (pll_cfg[0].rate == 0)
+		return -EINVAL;
+
+	best_rate = pll_cfg[0].rate;
+
+	for (i = 1; pll_cfg[i].rate != 0; i++) {
+		if (abs(rate - pll_cfg[i].rate) < abs(rate - best_rate))
+			best_rate = pll_cfg[i].rate;
+	}
+
+	pr_debug("chosen best rate: %lu\n", best_rate);
+
+	return best_rate;
+}
+
+static int hsdk_pll_comm_update_rate(struct hsdk_cgu_clk *clk,
+				     unsigned long rate,
+				     const struct hsdk_pll_cfg *cfg)
+{
+	hsdk_pll_set_cfg(clk, cfg);
+
+	/*
+	 * Wait until CGU relocks and check error status.
+	 * If after timeout CGU is unlocked yet return error.
+	 */
+	udelay(HSDK_PLL_MAX_LOCK_TIME);
+	if (!hsdk_pll_is_locked(clk))
+		return -ETIMEDOUT;
+
+	if (hsdk_pll_is_err(clk))
+		return -EINVAL;
+
+	return 0;
+}
+
+static int hsdk_pll_core_update_rate(struct hsdk_cgu_clk *clk,
+				     unsigned long rate,
+				     const struct hsdk_pll_cfg *cfg)
+{
+	/*
+	 * When core clock exceeds 500MHz, the divider for the interface
+	 * clock must be programmed to div-by-2.
+	 */
+	if (rate > CORE_IF_CLK_THRESHOLD_HZ)
+		hsdk_pll_spcwrite(clk, CREG_CORE_IF_DIV, CREG_CORE_IF_CLK_DIV_2);
+
+	hsdk_pll_set_cfg(clk, cfg);
+
+	/*
+	 * Wait until CGU relocks and check error status.
+	 * If after timeout CGU is unlocked yet return error.
+	 */
+	udelay(HSDK_PLL_MAX_LOCK_TIME);
+	if (!hsdk_pll_is_locked(clk))
+		return -ETIMEDOUT;
+
+	if (hsdk_pll_is_err(clk))
+		return -EINVAL;
+
+	/*
+	 * Program divider to div-by-1 if we succesfuly set core clock below
+	 * 500MHz threshold.
+	 */
+	if (rate <= CORE_IF_CLK_THRESHOLD_HZ)
+		hsdk_pll_spcwrite(clk, CREG_CORE_IF_DIV, CREG_CORE_IF_CLK_DIV_1);
+
+	return 0;
+}
+
+static ulong pll_set(struct clk *sclk, ulong rate)
+{
+	int i;
+	unsigned long best_rate;
+	struct hsdk_cgu_clk *clk = dev_get_priv(sclk->dev);
+	const struct hsdk_pll_cfg *pll_cfg = clk->pll_devdata->pll_cfg;
+
+	best_rate = hsdk_pll_round_rate(sclk, rate);
+
+	for (i = 0; pll_cfg[i].rate != 0; i++) {
+		if (pll_cfg[i].rate == best_rate) {
+			return clk->pll_devdata->update_rate(clk, best_rate,
+							     &pll_cfg[i]);
+		}
+	}
+
+	pr_err("invalid rate=%ld, parent_rate=%d\n", best_rate, PARENT_RATE);
+
+	return -EINVAL;
+}
+
+static int idiv_off(struct clk *sclk)
+{
+	struct hsdk_cgu_clk *clk = dev_get_priv(sclk->dev);
+
+	hsdk_idiv_write(clk, 0);
+
+	return 0;
+}
+
+static ulong idiv_get(struct clk *sclk)
+{
+	struct hsdk_cgu_clk *clk = dev_get_priv(sclk->dev);
+	ulong parent_rate = pll_get(sclk);
+	u32 div_factor = hsdk_idiv_read(clk);
+
+	div_factor &= CGU_IDIV_MASK;
+
+	pr_debug("current configurarion: %#x (%d)\n", div_factor, div_factor);
+
+	if (div_factor == 0)
+		return 0;
+
+	return parent_rate / div_factor;
+}
+
+static ulong idiv_set(struct clk *sclk, ulong rate)
+{
+	struct hsdk_cgu_clk *clk = dev_get_priv(sclk->dev);
+	ulong parent_rate = pll_get(sclk);
+	u32 div_factor;
+
+	div_factor = parent_rate / rate;
+	if (abs(rate - parent_rate / (div_factor + 1)) <=
+	    abs(rate - parent_rate / div_factor)) {
+		div_factor += 1;
+	}
+
+	if (div_factor & ~CGU_IDIV_MASK) {
+		pr_err("invalid rate=%ld, parent_rate=%ld, div=%d: max divider valie is%d\n",
+		       rate, parent_rate, div_factor, CGU_IDIV_MASK);
+
+		div_factor = CGU_IDIV_MASK;
+	}
+
+	if (div_factor == 0) {
+		pr_err("invalid rate=%ld, parent_rate=%ld, div=%d: min divider valie is 1\n",
+		       rate, parent_rate, div_factor);
+
+		div_factor = 1;
+	}
+
+	hsdk_idiv_write(clk, div_factor);
+
+	return 0;
+}
+
+static int hsdk_prepare_clock_tree_branch(struct clk *sclk)
+{
+	struct hsdk_cgu_clk *clk = dev_get_priv(sclk->dev);
+
+	if (sclk->id >= CGU_MAX_CLOCKS)
+		return -EINVAL;
+
+	clk->pll_devdata = clock_map[sclk->id].pll_devdata;
+	clk->regs = clk->cgu_regs + clock_map[sclk->id].cgu_pll_oft;
+	clk->spec_regs = clk->creg_regs + clock_map[sclk->id].creg_div_oft;
+	clk->idiv_regs = clk->cgu_regs + clock_map[sclk->id].cgu_div_oft;
+
+	return 0;
+}
+
+static ulong hsdk_cgu_get_rate(struct clk *sclk)
+{
+	if (hsdk_prepare_clock_tree_branch(sclk))
+		return -EINVAL;
+
+	return clock_map[sclk->id].get_rate(sclk);
+}
+
+static ulong hsdk_cgu_set_rate(struct clk *sclk, ulong rate)
+{
+	if (hsdk_prepare_clock_tree_branch(sclk))
+		return -EINVAL;
+
+	return clock_map[sclk->id].set_rate(sclk, rate);
+}
+
+static int hsdk_cgu_disable(struct clk *sclk)
+{
+	if (hsdk_prepare_clock_tree_branch(sclk))
+		return -EINVAL;
+
+	if (clock_map[sclk->id].disable)
+		return clock_map[sclk->id].disable(sclk);
+
+	return -ENOTSUPP;
+}
+
+static const struct clk_ops hsdk_cgu_ops = {
+	.set_rate = hsdk_cgu_set_rate,
+	.get_rate = hsdk_cgu_get_rate,
+	.disable = hsdk_cgu_disable,
+};
+
+static int hsdk_cgu_clk_probe(struct udevice *dev)
+{
+	struct hsdk_cgu_clk *pll_clk = dev_get_priv(dev);
+
+	BUILD_BUG_ON(ARRAY_SIZE(clock_map) != CGU_MAX_CLOCKS);
+
+	pll_clk->cgu_regs = (void __iomem *)devfdt_get_addr_index(dev, 0);
+	if (!pll_clk->cgu_regs)
+		return -EINVAL;
+
+	pll_clk->creg_regs = (void __iomem *)devfdt_get_addr_index(dev, 1);
+	if (!pll_clk->creg_regs)
+		return -EINVAL;
+
+	return 0;
+}
+
+static const struct udevice_id hsdk_cgu_clk_id[] = {
+	{ .compatible = "snps,hsdk-cgu-clock" },
+	{ }
+};
+
+U_BOOT_DRIVER(hsdk_cgu_clk) = {
+	.name = "hsdk-cgu-clk",
+	.id = UCLASS_CLK,
+	.of_match = hsdk_cgu_clk_id,
+	.probe = hsdk_cgu_clk_probe,
+	.platdata_auto_alloc_size = sizeof(struct hsdk_cgu_clk),
+	.ops = &hsdk_cgu_ops,
+};
--- a/include/dt-bindings/clock/snps,hsdk-cgu.h
+++ b/include/dt-bindings/clock/snps,hsdk-cgu.h
@ -0,0 +1,40 @@
+/*
+ * Synopsys HSDK SDP CGU clock driver dts bindings
+ *
+ * Copyright (C) 2017 Synopsys
+ * Author: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#ifndef __DT_BINDINGS_CLK_HSDK_CGU_H_
+#define __DT_BINDINGS_CLK_HSDK_CGU_H_
+
+#define CLK_ARC_PLL		0
+#define CLK_ARC			1
+#define CLK_DDR_PLL		2
+#define CLK_SYS_PLL		3
+#define CLK_SYS_APB		4
+#define CLK_SYS_AXI		5
+#define CLK_SYS_ETH		6
+#define CLK_SYS_USB		7
+#define CLK_SYS_SDIO		8
+#define CLK_SYS_HDMI		9
+#define CLK_SYS_GFX_CORE	10
+#define CLK_SYS_GFX_DMA		11
+#define CLK_SYS_GFX_CFG		12
+#define CLK_SYS_DMAC_CORE	13
+#define CLK_SYS_DMAC_CFG	14
+#define CLK_SYS_SDIO_REF	15
+#define CLK_SYS_SPI_REF		16
+#define CLK_SYS_I2C_REF		17
+#define CLK_SYS_UART_REF	18
+#define CLK_SYS_EBI_REF		19
+#define CLK_TUN_PLL		20
+#define CLK_TUN			21
+#define CLK_HDMI_PLL		22
+#define CLK_HDMI		23
+
+#endif /* __DT_BINDINGS_CLK_HSDK_CGU_H_ */