clk: at91: Add clock driver

The patch is referred to at91 clock driver of Linux, to make
the clock node descriptions in DT aligned with the Linux's.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/mach-at91/include/mach/at91_pmc.h b/arch/arm/mach-at91/include/mach/at91_pmc.h
index 680ceb0..2875ff2 100644
--- a/arch/arm/mach-at91/include/mach/at91_pmc.h
+++ b/arch/arm/mach-at91/include/mach/at91_pmc.h
@@ -149,6 +149,9 @@
 
 #define AT91_PMC_PCR_PID_MASK		(0x3f)
 #define AT91_PMC_PCR_GCKCSS		(0x7 << 8)
+#define AT91_PMC_PCR_GCKCSS_MASK	0x07
+#define AT91_PMC_PCR_GCKCSS_OFFSET	8
+#define AT91_PMC_PCR_GCKCSS_(x)		((x & 0x07) << 8)
 #define		AT91_PMC_PCR_GCKCSS_SLOW_CLK	(0x0 << 8)
 #define		AT91_PMC_PCR_GCKCSS_MAIN_CLK	(0x1 << 8)
 #define		AT91_PMC_PCR_GCKCSS_PLLA_CLK	(0x2 << 8)
@@ -158,8 +161,9 @@
 #define AT91_PMC_PCR_CMD_WRITE		(0x1 << 12)
 #define AT91_PMC_PCR_DIV		(0x3 << 16)
 #define AT91_PMC_PCR_GCKDIV		(0xff << 20)
-#define		AT91_PMC_PCR_GCKDIV_(x)		(((x) & 0xff) << 20)
-#define		AT91_PMC_PCR_GCKDIV_OFFSET	20
+#define AT91_PMC_PCR_GCKDIV_MASK	0xff
+#define AT91_PMC_PCR_GCKDIV_OFFSET	20
+#define AT91_PMC_PCR_GCKDIV_(x)		((x & 0xff) << 20)
 #define AT91_PMC_PCR_EN			(0x1 << 28)
 #define AT91_PMC_PCR_GCKEN		(0x1 << 29)
 
@@ -243,8 +247,9 @@
 #define		AT91_PMC_PCK1RDY	(1 <<  9)		/* Programmable Clock 1 */
 #define		AT91_PMC_PCK2RDY	(1 << 10)		/* Programmable Clock 2 */
 #define		AT91_PMC_PCK3RDY	(1 << 11)		/* Programmable Clock 3 */
+#define		AT91_PMC_MOSCSELS	BIT(16)			/* Main Oscillator Selection Status */
+#define		AT91_PMC_MOSCRCS	BIT(17)			/* 12 MHz RC Oscillator Status */
 #define		AT91_PMC_GCKRDY		(1 << 24)
-
 #define		AT91_PMC_PROTKEY	0x504d4301	/* Activation Code */
 
 /* PLL Charge Pump Current Register (PMC_PLLICPR) */
diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index 6eee8eb..3da63c0 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -22,5 +22,6 @@
 
 source "drivers/clk/uniphier/Kconfig"
 source "drivers/clk/exynos/Kconfig"
+source "drivers/clk/at91/Kconfig"
 
 endmenu
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 3cbdd54..65de008 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -12,3 +12,4 @@
 obj-$(CONFIG_MACH_PIC32) += clk_pic32.o
 obj-$(CONFIG_CLK_UNIPHIER) += uniphier/
 obj-$(CONFIG_CLK_EXYNOS) += exynos/
+obj-$(CONFIG_CLK_AT91) += at91/
diff --git a/drivers/clk/at91/Kconfig b/drivers/clk/at91/Kconfig
new file mode 100644
index 0000000..10050d8
--- /dev/null
+++ b/drivers/clk/at91/Kconfig
@@ -0,0 +1,43 @@
+config CLK_AT91
+	bool "AT91 clock drivers"
+	depends on CLK
+	help
+	  This option is used to enable the AT91 clock driver.
+	  The driver supports the AT91 clock generator, including
+	  the oscillators and PLLs, such as main clock, slow clock,
+	  PLLA, UTMI PLL. Clocks can also be a source clock of other
+	  clocks a tree structure, such as master clock, usb device
+	  clock, matrix clock and generic clock.
+	  Devices can use a common clock API to request a particular
+	  clock, enable it and get its rate.
+
+config AT91_UTMI
+	bool "Support UTMI PLL Clock"
+	depends on CLK_AT91
+	help
+	  This option is used to enable the AT91 UTMI PLL clock
+	  driver. It is the clock provider of USB, and UPLLCK is the
+	  output of 480 MHz UTMI PLL, The souce clock of the UTMI
+	  PLL is the main clock, so the main clock must select the
+	  fast crystal oscillator to meet the frequency accuracy
+	  required by USB.
+
+config AT91_H32MX
+	bool "Support H32MX 32-bit Matrix Clock"
+	depends on CLK_AT91
+	help
+	  This option is used to enable the AT91 H32MX matrixes
+	  clock driver. There are H64MX and H32MX matrixes clocks,
+	  H64MX 64-bit matrix clocks are MCK. The H32MX 32-bit
+	  matrix clock is to be configured as MCK if MCK does not
+	  exceed 83 MHz, else it is to be configured as MCK/2.
+
+config AT91_GENERIC_CLK
+	bool "Support Generic Clock"
+	depends on CLK_AT91
+	help
+	  This option is used to enable the AT91 generic clock
+	  driver. Some peripherals may need a second clock source
+	  that may be different from the system clock. This second
+	  clock is the generic clock (GCLK) and is managed by
+	  the PMC via PMC_PCR register.
diff --git a/drivers/clk/at91/Makefile b/drivers/clk/at91/Makefile
new file mode 100644
index 0000000..fbe3cb6
--- /dev/null
+++ b/drivers/clk/at91/Makefile
@@ -0,0 +1,11 @@
+#
+# Makefile for at91 specific clk
+#
+
+obj-y += pmc.o sckc.o
+obj-y += clk-slow.o clk-main.o clk-plla.o clk-master.o
+obj-y += clk-system.o clk-peripheral.o
+
+obj-$(CONFIG_AT91_UTMI)		+= clk-utmi.o
+obj-$(CONFIG_AT91_H32MX)	+= clk-h32mx.o
+obj-$(CONFIG_AT91_GENERIC_CLK)	+= clk-generated.o
diff --git a/drivers/clk/at91/clk-generated.c b/drivers/clk/at91/clk-generated.c
new file mode 100644
index 0000000..f6164cc
--- /dev/null
+++ b/drivers/clk/at91/clk-generated.c
@@ -0,0 +1,162 @@
+/*
+ * Copyright (C) 2016 Atmel Corporation
+ *               Wenyou.Yang <wenyou.yang@atmel.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <clk-uclass.h>
+#include <dm/device.h>
+#include <linux/io.h>
+#include <mach/at91_pmc.h>
+#include "pmc.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define GENERATED_SOURCE_MAX	6
+#define GENERATED_MAX_DIV	255
+
+struct generated_clk_priv {
+	u32 num_parents;
+};
+
+static ulong generated_clk_get_rate(struct clk *clk)
+{
+	struct pmc_platdata *plat = dev_get_platdata(clk->dev);
+	struct at91_pmc *pmc = plat->reg_base;
+	struct clk parent;
+	u32 tmp, gckdiv;
+	u8 parent_id;
+	int ret;
+
+	writel(clk->id & AT91_PMC_PCR_PID_MASK, &pmc->pcr);
+	tmp = readl(&pmc->pcr);
+	parent_id = (tmp >> AT91_PMC_PCR_GCKCSS_OFFSET) &
+		    AT91_PMC_PCR_GCKCSS_MASK;
+	gckdiv = (tmp >> AT91_PMC_PCR_GCKDIV_OFFSET) & AT91_PMC_PCR_GCKDIV_MASK;
+
+	ret = clk_get_by_index(clk->dev, parent_id, &parent);
+	if (ret)
+		return 0;
+
+	return clk_get_rate(&parent) / (gckdiv + 1);
+}
+
+static ulong generated_clk_set_rate(struct clk *clk, ulong rate)
+{
+	struct pmc_platdata *plat = dev_get_platdata(clk->dev);
+	struct at91_pmc *pmc = plat->reg_base;
+	struct generated_clk_priv *priv = dev_get_priv(clk->dev);
+	struct clk parent, best_parent;
+	ulong tmp_rate, best_rate = rate, parent_rate;
+	int tmp_diff, best_diff = -1;
+	u32 div, best_div = 0;
+	u8 best_parent_id = 0;
+	u8 i;
+	u32 tmp;
+	int ret;
+
+	for (i = 0; i < priv->num_parents; i++) {
+		ret = clk_get_by_index(clk->dev, i, &parent);
+		if (ret)
+			return ret;
+
+		parent_rate = clk_get_rate(&parent);
+		if (IS_ERR_VALUE(parent_rate))
+			return parent_rate;
+
+		for (div = 1; div < GENERATED_MAX_DIV + 2; div++) {
+			tmp_rate = DIV_ROUND_CLOSEST(parent_rate, div);
+			if (rate < tmp_rate)
+				continue;
+			tmp_diff = rate - tmp_rate;
+
+			if (best_diff < 0 || best_diff > tmp_diff) {
+				best_rate = tmp_rate;
+				best_diff = tmp_diff;
+
+				best_div = div - 1;
+				best_parent = parent;
+				best_parent_id = i;
+			}
+
+			if (!best_diff || tmp_rate < rate)
+				break;
+		}
+
+		if (!best_diff)
+			break;
+	}
+
+	debug("GCK: best parent: %s, best_rate = %ld, best_div = %d\n",
+	      best_parent.dev->name, best_rate, best_div);
+
+	ret = clk_enable(&best_parent);
+	if (ret)
+		return ret;
+
+	writel(clk->id & AT91_PMC_PCR_PID_MASK, &pmc->pcr);
+	tmp = readl(&pmc->pcr);
+	tmp &= ~(AT91_PMC_PCR_GCKDIV | AT91_PMC_PCR_GCKCSS);
+	tmp |= AT91_PMC_PCR_GCKCSS_(best_parent_id) |
+	       AT91_PMC_PCR_CMD_WRITE |
+	       AT91_PMC_PCR_GCKDIV_(best_div) |
+	       AT91_PMC_PCR_GCKEN;
+	writel(tmp, &pmc->pcr);
+
+	while (!(readl(&pmc->sr) & AT91_PMC_GCKRDY))
+		;
+
+	return 0;
+}
+
+static struct clk_ops generated_clk_ops = {
+	.get_rate = generated_clk_get_rate,
+	.set_rate = generated_clk_set_rate,
+};
+
+static int generated_clk_ofdata_to_platdata(struct udevice *dev)
+{
+	struct generated_clk_priv *priv = dev_get_priv(dev);
+	u32 cells[GENERATED_SOURCE_MAX];
+	u32 num_parents;
+
+	num_parents = fdtdec_get_int_array_count(gd->fdt_blob, dev->of_offset,
+						 "clocks", cells,
+						 GENERATED_SOURCE_MAX);
+
+	if (!num_parents)
+		return -1;
+
+	priv->num_parents = num_parents;
+
+	return 0;
+}
+
+static int generated_clk_bind(struct udevice *dev)
+{
+	return at91_pmc_clk_node_bind(dev);
+}
+
+static int generated_clk_probe(struct udevice *dev)
+{
+	return at91_pmc_core_probe(dev);
+}
+
+static const struct udevice_id generated_clk_match[] = {
+	{ .compatible = "atmel,sama5d2-clk-generated" },
+	{}
+};
+
+U_BOOT_DRIVER(generated_clk) = {
+	.name = "generated-clk",
+	.id = UCLASS_CLK,
+	.of_match = generated_clk_match,
+	.bind = generated_clk_bind,
+	.probe = generated_clk_probe,
+	.ofdata_to_platdata = generated_clk_ofdata_to_platdata,
+	.priv_auto_alloc_size = sizeof(struct generated_clk_priv),
+	.platdata_auto_alloc_size = sizeof(struct pmc_platdata),
+	.ops = &generated_clk_ops,
+};
diff --git a/drivers/clk/at91/clk-h32mx.c b/drivers/clk/at91/clk-h32mx.c
new file mode 100644
index 0000000..1a304ba
--- /dev/null
+++ b/drivers/clk/at91/clk-h32mx.c
@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2016 Atmel Corporation
+ *               Wenyou.Yang <wenyou.yang@atmel.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <clk-uclass.h>
+#include <dm/device.h>
+#include <dm/util.h>
+#include <linux/io.h>
+#include <mach/at91_pmc.h>
+#include "pmc.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define H32MX_MAX_FREQ	90000000
+
+static ulong sama5d4_h32mx_clk_get_rate(struct clk *clk)
+{
+	struct pmc_platdata *plat = dev_get_platdata(clk->dev);
+	struct at91_pmc *pmc = plat->reg_base;
+	ulong rate = gd->arch.mck_rate_hz;
+
+	if (readl(&pmc->mckr) & AT91_PMC_MCKR_H32MXDIV)
+		rate /= 2;
+
+	if (rate > H32MX_MAX_FREQ)
+		dm_warn("H32MX clock is too fast\n");
+
+	return rate;
+}
+
+static struct clk_ops sama5d4_h32mx_clk_ops = {
+	.get_rate = sama5d4_h32mx_clk_get_rate,
+};
+
+static int sama5d4_h32mx_clk_probe(struct udevice *dev)
+{
+	return at91_pmc_core_probe(dev);
+}
+
+static const struct udevice_id sama5d4_h32mx_clk_match[] = {
+	{ .compatible = "atmel,sama5d4-clk-h32mx" },
+	{}
+};
+
+U_BOOT_DRIVER(sama5d4_h32mx_clk) = {
+	.name = "sama5d4-h32mx-clk",
+	.id = UCLASS_CLK,
+	.of_match = sama5d4_h32mx_clk_match,
+	.probe = sama5d4_h32mx_clk_probe,
+	.platdata_auto_alloc_size = sizeof(struct pmc_platdata),
+	.ops = &sama5d4_h32mx_clk_ops,
+};
diff --git a/drivers/clk/at91/clk-main.c b/drivers/clk/at91/clk-main.c
new file mode 100644
index 0000000..252d076
--- /dev/null
+++ b/drivers/clk/at91/clk-main.c
@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2016 Atmel Corporation
+ *               Wenyou.Yang <wenyou.yang@atmel.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <clk-uclass.h>
+#include <dm/device.h>
+#include <linux/io.h>
+#include <mach/at91_pmc.h>
+#include "pmc.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static int main_osc_clk_enable(struct clk *clk)
+{
+	struct pmc_platdata *plat = dev_get_platdata(clk->dev);
+	struct at91_pmc *pmc = plat->reg_base;
+
+	if (readl(&pmc->sr) & AT91_PMC_MOSCSELS)
+		return 0;
+
+	return -EINVAL;
+}
+
+static ulong main_osc_clk_get_rate(struct clk *clk)
+{
+	return gd->arch.main_clk_rate_hz;
+}
+
+static struct clk_ops main_osc_clk_ops = {
+	.enable = main_osc_clk_enable,
+	.get_rate = main_osc_clk_get_rate,
+};
+
+static int main_osc_clk_probe(struct udevice *dev)
+{
+	return at91_pmc_core_probe(dev);
+}
+
+static const struct udevice_id main_osc_clk_match[] = {
+	{ .compatible = "atmel,at91sam9x5-clk-main" },
+	{}
+};
+
+U_BOOT_DRIVER(at91sam9x5_main_osc_clk) = {
+	.name = "at91sam9x5-main-osc-clk",
+	.id = UCLASS_CLK,
+	.of_match = main_osc_clk_match,
+	.probe = main_osc_clk_probe,
+	.platdata_auto_alloc_size = sizeof(struct pmc_platdata),
+	.ops = &main_osc_clk_ops,
+};
diff --git a/drivers/clk/at91/clk-master.c b/drivers/clk/at91/clk-master.c
new file mode 100644
index 0000000..284b248
--- /dev/null
+++ b/drivers/clk/at91/clk-master.c
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2016 Atmel Corporation
+ *               Wenyou.Yang <wenyou.yang@atmel.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <clk-uclass.h>
+#include <dm/device.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static ulong at91_master_clk_get_rate(struct clk *clk)
+{
+	return gd->arch.mck_rate_hz;
+}
+
+static struct clk_ops at91_master_clk_ops = {
+	.get_rate = at91_master_clk_get_rate,
+};
+
+static const struct udevice_id at91_master_clk_match[] = {
+	{ .compatible = "atmel,at91sam9x5-clk-master" },
+	{}
+};
+
+U_BOOT_DRIVER(at91_master_clk) = {
+	.name = "at91-master-clk",
+	.id = UCLASS_CLK,
+	.of_match = at91_master_clk_match,
+	.ops = &at91_master_clk_ops,
+};
diff --git a/drivers/clk/at91/clk-peripheral.c b/drivers/clk/at91/clk-peripheral.c
new file mode 100644
index 0000000..16688e9
--- /dev/null
+++ b/drivers/clk/at91/clk-peripheral.c
@@ -0,0 +1,60 @@
+/*
+ * Copyright (C) 2016 Atmel Corporation
+ *               Wenyou.Yang <wenyou.yang@atmel.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <clk-uclass.h>
+#include <dm/device.h>
+#include <linux/io.h>
+#include <mach/at91_pmc.h>
+#include "pmc.h"
+
+#define PERIPHERAL_ID_MIN	2
+#define PERIPHERAL_ID_MAX	31
+#define PERIPHERAL_MASK(id)	(1 << ((id) & PERIPHERAL_ID_MAX))
+
+static int sam9x5_periph_clk_enable(struct clk *clk)
+{
+	struct pmc_platdata *plat = dev_get_platdata(clk->dev);
+	struct at91_pmc *pmc = plat->reg_base;
+
+	if (clk->id < PERIPHERAL_ID_MIN)
+		return -1;
+
+	writel(clk->id & AT91_PMC_PCR_PID_MASK, &pmc->pcr);
+	setbits_le32(&pmc->pcr, AT91_PMC_PCR_CMD_WRITE | AT91_PMC_PCR_EN);
+
+	return 0;
+}
+
+static struct clk_ops sam9x5_periph_clk_ops = {
+	.enable = sam9x5_periph_clk_enable,
+};
+
+static int sam9x5_periph_clk_bind(struct udevice *dev)
+{
+	return at91_pmc_clk_node_bind(dev);
+}
+
+static int sam9x5_periph_clk_probe(struct udevice *dev)
+{
+	return at91_pmc_core_probe(dev);
+}
+
+static const struct udevice_id sam9x5_periph_clk_match[] = {
+	{ .compatible = "atmel,at91sam9x5-clk-peripheral" },
+	{}
+};
+
+U_BOOT_DRIVER(sam9x5_periph_clk) = {
+	.name = "sam9x5-periph-clk",
+	.id = UCLASS_CLK,
+	.of_match = sam9x5_periph_clk_match,
+	.bind = sam9x5_periph_clk_bind,
+	.probe = sam9x5_periph_clk_probe,
+	.platdata_auto_alloc_size = sizeof(struct pmc_platdata),
+	.ops = &sam9x5_periph_clk_ops,
+};
diff --git a/drivers/clk/at91/clk-plla.c b/drivers/clk/at91/clk-plla.c
new file mode 100644
index 0000000..2a71399
--- /dev/null
+++ b/drivers/clk/at91/clk-plla.c
@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2016 Atmel Corporation
+ *               Wenyou.Yang <wenyou.yang@atmel.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <clk-uclass.h>
+#include <dm/device.h>
+#include <linux/io.h>
+#include <mach/at91_pmc.h>
+#include "pmc.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static int plla_clk_enable(struct clk *clk)
+{
+	struct pmc_platdata *plat = dev_get_platdata(clk->dev);
+	struct at91_pmc *pmc = plat->reg_base;
+
+	if (readl(&pmc->sr) & AT91_PMC_LOCKA)
+		return 0;
+
+	return -EINVAL;
+}
+
+static ulong plla_clk_get_rate(struct clk *clk)
+{
+	return gd->arch.plla_rate_hz;
+}
+
+static struct clk_ops plla_clk_ops = {
+	.enable = plla_clk_enable,
+	.get_rate = plla_clk_get_rate,
+};
+
+static int plla_clk_probe(struct udevice *dev)
+{
+	return at91_pmc_core_probe(dev);
+}
+
+static const struct udevice_id plla_clk_match[] = {
+	{ .compatible = "atmel,sama5d3-clk-pll" },
+	{}
+};
+
+U_BOOT_DRIVER(at91_plla_clk) = {
+	.name = "at91-plla-clk",
+	.id = UCLASS_CLK,
+	.of_match = plla_clk_match,
+	.probe = plla_clk_probe,
+	.platdata_auto_alloc_size = sizeof(struct pmc_platdata),
+	.ops = &plla_clk_ops,
+};
diff --git a/drivers/clk/at91/clk-slow.c b/drivers/clk/at91/clk-slow.c
new file mode 100644
index 0000000..f7666b4
--- /dev/null
+++ b/drivers/clk/at91/clk-slow.c
@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2016 Atmel Corporation
+ *               Wenyou.Yang <wenyou.yang@atmel.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <clk-uclass.h>
+#include <dm/device.h>
+
+static int at91_slow_clk_enable(struct clk *clk)
+{
+	return 0;
+}
+
+static ulong at91_slow_clk_get_rate(struct clk *clk)
+{
+	return CONFIG_SYS_AT91_SLOW_CLOCK;
+}
+
+static struct clk_ops at91_slow_clk_ops = {
+	.enable = at91_slow_clk_enable,
+	.get_rate = at91_slow_clk_get_rate,
+};
+
+static const struct udevice_id at91_slow_clk_match[] = {
+	{ .compatible = "atmel,at91sam9x5-clk-slow" },
+	{}
+};
+
+U_BOOT_DRIVER(at91_slow_clk) = {
+	.name = "at91-slow-clk",
+	.id = UCLASS_CLK,
+	.of_match = at91_slow_clk_match,
+	.ops = &at91_slow_clk_ops,
+};
diff --git a/drivers/clk/at91/clk-system.c b/drivers/clk/at91/clk-system.c
new file mode 100644
index 0000000..fa80bad
--- /dev/null
+++ b/drivers/clk/at91/clk-system.c
@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2016 Atmel Corporation
+ *               Wenyou.Yang <wenyou.yang@atmel.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <clk-uclass.h>
+#include <dm/device.h>
+#include <linux/io.h>
+#include <mach/at91_pmc.h>
+#include "pmc.h"
+
+#define SYSTEM_MAX_ID		31
+
+static inline int is_pck(int id)
+{
+	return (id >= 8) && (id <= 15);
+}
+
+static int at91_system_clk_enable(struct clk *clk)
+{
+	struct pmc_platdata *plat = dev_get_platdata(clk->dev);
+	struct at91_pmc *pmc = plat->reg_base;
+	u32 mask;
+
+	if (clk->id > SYSTEM_MAX_ID)
+		return -EINVAL;
+
+	mask = BIT(clk->id);
+
+	writel(mask, &pmc->scer);
+
+	/**
+	 * For the programmable clocks the Ready status in the PMC
+	 * status register should be checked after enabling.
+	 * For other clocks this is unnecessary.
+	 */
+	if (!is_pck(clk->id))
+		return 0;
+
+	while (!(readl(&pmc->sr) & mask))
+		;
+
+	return 0;
+}
+
+static struct clk_ops at91_system_clk_ops = {
+	.enable = at91_system_clk_enable,
+};
+
+static int at91_system_clk_bind(struct udevice *dev)
+{
+	return at91_pmc_clk_node_bind(dev);
+}
+
+static int at91_system_clk_probe(struct udevice *dev)
+{
+	return at91_pmc_core_probe(dev);
+}
+
+static const struct udevice_id at91_system_clk_match[] = {
+	{ .compatible = "atmel,at91rm9200-clk-system" },
+	{}
+};
+
+U_BOOT_DRIVER(at91_system_clk) = {
+	.name = "at91-system-clk",
+	.id = UCLASS_CLK,
+	.of_match = at91_system_clk_match,
+	.bind = at91_system_clk_bind,
+	.probe = at91_system_clk_probe,
+	.platdata_auto_alloc_size = sizeof(struct pmc_platdata),
+	.ops = &at91_system_clk_ops,
+};
diff --git a/drivers/clk/at91/clk-utmi.c b/drivers/clk/at91/clk-utmi.c
new file mode 100644
index 0000000..369a687
--- /dev/null
+++ b/drivers/clk/at91/clk-utmi.c
@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2016 Atmel Corporation
+ *               Wenyou.Yang <wenyou.yang@atmel.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <clk-uclass.h>
+#include <dm/device.h>
+#include <linux/io.h>
+#include <mach/at91_pmc.h>
+#include "pmc.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define UTMI_FIXED_MUL		40
+
+static int utmi_clk_enable(struct clk *clk)
+{
+	struct pmc_platdata *plat = dev_get_platdata(clk->dev);
+	struct at91_pmc *pmc = plat->reg_base;
+	u32 tmp;
+
+	if (readl(&pmc->sr) & AT91_PMC_LOCKU)
+		return 0;
+
+	tmp = readl(&pmc->uckr);
+	tmp |= AT91_PMC_UPLLEN |
+	       AT91_PMC_UPLLCOUNT |
+	       AT91_PMC_BIASEN;
+	writel(tmp, &pmc->uckr);
+
+	while (!(readl(&pmc->sr) & AT91_PMC_LOCKU))
+		;
+
+	return 0;
+}
+
+static ulong utmi_clk_get_rate(struct clk *clk)
+{
+	return gd->arch.main_clk_rate_hz * UTMI_FIXED_MUL;
+}
+
+static struct clk_ops utmi_clk_ops = {
+	.enable = utmi_clk_enable,
+	.get_rate = utmi_clk_get_rate,
+};
+
+static int utmi_clk_probe(struct udevice *dev)
+{
+	return at91_pmc_core_probe(dev);
+}
+
+static const struct udevice_id utmi_clk_match[] = {
+	{ .compatible = "atmel,at91sam9x5-clk-utmi" },
+	{}
+};
+
+U_BOOT_DRIVER(at91sam9x5_utmi_clk) = {
+	.name = "at91sam9x5-utmi-clk",
+	.id = UCLASS_CLK,
+	.of_match = utmi_clk_match,
+	.probe = utmi_clk_probe,
+	.platdata_auto_alloc_size = sizeof(struct pmc_platdata),
+	.ops = &utmi_clk_ops,
+};
diff --git a/drivers/clk/at91/pmc.c b/drivers/clk/at91/pmc.c
new file mode 100644
index 0000000..a08d7e8
--- /dev/null
+++ b/drivers/clk/at91/pmc.c
@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2016 Atmel Corporation
+ *               Wenyou.Yang <wenyou.yang@atmel.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <clk-uclass.h>
+#include <dm/device.h>
+#include <dm/lists.h>
+#include <dm/root.h>
+#include "pmc.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static int at91_pmc_bind(struct udevice *dev)
+{
+	return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false);
+}
+
+static const struct udevice_id at91_pmc_match[] = {
+	{ .compatible = "atmel,sama5d2-pmc" },
+	{}
+};
+
+U_BOOT_DRIVER(at91_pmc) = {
+	.name = "at91-pmc-core",
+	.id = UCLASS_CLK,
+	.of_match = at91_pmc_match,
+	.bind = at91_pmc_bind,
+};
+
+int at91_pmc_core_probe(struct udevice *dev)
+{
+	struct pmc_platdata *plat = dev_get_platdata(dev);
+
+	dev = dev_get_parent(dev);
+
+	plat->reg_base = (struct at91_pmc *)dev_get_addr_ptr(dev);
+
+	return 0;
+}
+
+int at91_pmc_clk_node_bind(struct udevice *dev)
+{
+	const void *fdt = gd->fdt_blob;
+	int offset = dev->of_offset;
+	const char *name;
+	int ret;
+
+	for (offset = fdt_first_subnode(fdt, offset);
+	     offset > 0;
+	     offset = fdt_next_subnode(fdt, offset)) {
+		name = fdt_get_name(fdt, offset, NULL);
+		if (!name)
+			return -EINVAL;
+
+		ret = device_bind_driver_to_node(dev, "clk", name,
+						 offset, NULL);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+U_BOOT_DRIVER(clk_generic) = {
+	.id	= UCLASS_CLK,
+	.name	= "clk",
+};
diff --git a/drivers/clk/at91/pmc.h b/drivers/clk/at91/pmc.h
new file mode 100644
index 0000000..5444c84
--- /dev/null
+++ b/drivers/clk/at91/pmc.h
@@ -0,0 +1,18 @@
+/*
+ * Copyright (C) 2016 Atmel Corporation
+ *               Wenyou.Yang <wenyou.yang@atmel.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __AT91_PMC_H__
+#define __AT91_PMC_H__
+
+struct pmc_platdata {
+	struct at91_pmc *reg_base;
+};
+
+int at91_pmc_core_probe(struct udevice *dev);
+int at91_pmc_clk_node_bind(struct udevice *dev);
+
+#endif
diff --git a/drivers/clk/at91/sckc.c b/drivers/clk/at91/sckc.c
new file mode 100644
index 0000000..b207611
--- /dev/null
+++ b/drivers/clk/at91/sckc.c
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2016 Atmel Corporation
+ *               Wenyou.Yang <wenyou.yang@atmel.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <clk-uclass.h>
+#include <dm/device.h>
+#include <dm/root.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static int at91_sckc_clk_bind(struct udevice *dev)
+{
+	return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false);
+}
+
+static const struct udevice_id at91_sckc_clk_match[] = {
+	{ .compatible = "atmel,at91sam9x5-sckc" },
+	{}
+};
+
+U_BOOT_DRIVER(at91_sckc_clk) = {
+	.name = "at91_sckc_clk",
+	.id = UCLASS_CLK,
+	.of_match = at91_sckc_clk_match,
+	.bind = at91_sckc_clk_bind,
+};