clk: exynos: add clock driver for Exynos7420 Soc

Add a clock driver for Exynos7420 SoC. There are about 25 clock controller
blocks in Exynos7420 out of which support for topc, top0 and peric1 blocks
are added in this initial version of the driver.

Cc: Minkyu Kang <mk7.kang@samsung.com>
Cc: Simon Glass <sjg@chromium.org>
Signed-off-by: Thomas Abraham <thomas.ab@samsung.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>

7 files changed, 307 insertions, 0 deletions

diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index a98b74b..6eee8eb 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -21,5 +21,6 @@ config SPL_CLK
 	  used as U-Boot proper.
 
 source "drivers/clk/uniphier/Kconfig"
+source "drivers/clk/exynos/Kconfig"
 
 endmenu
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index c51db15..81fe600 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -11,3 +11,4 @@ obj-$(CONFIG_ROCKCHIP_RK3288) += clk_rk3288.o
 obj-$(CONFIG_SANDBOX) += clk_sandbox.o
 obj-$(CONFIG_MACH_PIC32) += clk_pic32.o
 obj-$(CONFIG_CLK_UNIPHIER) += uniphier/
+obj-$(CONFIG_CLK_EXYNOS) += exynos/
diff --git a/drivers/clk/exynos/Kconfig b/drivers/clk/exynos/Kconfig
new file mode 100644
index 0000000..eb0efa9
--- /dev/null
+++ b/drivers/clk/exynos/Kconfig
@@ -0,0 +1,18 @@
+config CLK_EXYNOS
+	bool
+	select CLK
+	help
+	  This enables support for common clock driver API on Samsung
+	  Exynos SoCs.
+
+menu "Clock drivers for Exynos SoCs"
+	depends on CLK_EXYNOS
+
+config CLK_EXYNOS7420
+	bool "Clock driver for Samsung's Exynos7420 SoC"
+	default y
+	help
+	  This enables common clock driver support for platforms based
+	  on Samsung Exynos7420 SoC.
+
+endmenu
diff --git a/drivers/clk/exynos/Makefile b/drivers/clk/exynos/Makefile
new file mode 100644
index 0000000..1df10fe
--- /dev/null
+++ b/drivers/clk/exynos/Makefile
@@ -0,0 +1,9 @@
+#
+# Copyright (C) 2016 Samsung Electronics
+# Thomas Abraham <thomas.ab@samsung.com>
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+obj-y				+= clk-pll.o
+obj-$(CONFIG_CLK_EXYNOS7420)	+= clk-exynos7420.o
diff --git a/drivers/clk/exynos/clk-exynos7420.c b/drivers/clk/exynos/clk-exynos7420.c
new file mode 100644
index 0000000..bf5d0e6
--- /dev/null
+++ b/drivers/clk/exynos/clk-exynos7420.c
@@ -0,0 +1,236 @@
+/*
+ * Samsung Exynos7420 clock driver.
+ * Copyright (C) 2016 Samsung Electronics
+ * Thomas Abraham <thomas.ab@samsung.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <clk.h>
+#include <asm/io.h>
+#include <dt-bindings/clock/exynos7420-clk.h>
+#include "clk-pll.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define DIVIDER(reg, shift, mask)	\
+	(((readl(reg) >> shift) & mask) + 1)
+
+/* CMU TOPC block device structure */
+struct exynos7420_clk_cmu_topc {
+	unsigned int	rsvd1[68];
+	unsigned int	bus0_pll_con[2];
+	unsigned int	rsvd2[2];
+	unsigned int	bus1_pll_con[2];
+	unsigned int	rsvd3[54];
+	unsigned int	mux_sel[6];
+	unsigned int	rsvd4[250];
+	unsigned int	div[4];
+};
+
+/* CMU TOP0 block device structure */
+struct exynos7420_clk_cmu_top0 {
+	unsigned int	rsvd0[128];
+	unsigned int	mux_sel[7];
+	unsigned int	rsvd1[261];
+	unsigned int	div_peric[5];
+};
+
+/**
+ * struct exynos7420_clk_topc_priv - private data for CMU topc clock driver.
+ *
+ * @topc: base address of the memory mapped CMU TOPC controller.
+ * @fin_freq: frequency of the Oscillator clock.
+ * @sclk_bus0_pll_a: frequency of sclk_bus0_pll_a clock.
+ * @sclk_bus1_pll_a: frequency of sclk_bus1_pll_a clock.
+ */
+struct exynos7420_clk_topc_priv {
+	struct exynos7420_clk_cmu_topc *topc;
+	unsigned long fin_freq;
+	unsigned long sclk_bus0_pll_a;
+	unsigned long sclk_bus1_pll_a;
+};
+
+/**
+ * struct exynos7420_clk_top0_priv - private data for CMU top0 clock driver.
+ *
+ * @top0: base address of the memory mapped CMU TOP0 controller.
+ * @mout_top0_bus0_pll_half: frequency of mout_top0_bus0_pll_half clock
+ * @sclk_uart2: frequency of sclk_uart2 clock.
+ */
+struct exynos7420_clk_top0_priv {
+	struct exynos7420_clk_cmu_top0 *top0;
+	unsigned long mout_top0_bus0_pll_half;
+	unsigned long sclk_uart2;
+};
+
+static ulong exynos7420_topc_get_periph_rate(struct udevice *dev, int periph)
+{
+	struct exynos7420_clk_topc_priv *priv = dev_get_priv(dev);
+
+	switch (periph) {
+	case DOUT_SCLK_BUS0_PLL:
+	case SCLK_BUS0_PLL_A:
+	case SCLK_BUS0_PLL_B:
+		return priv->sclk_bus0_pll_a;
+	case DOUT_SCLK_BUS1_PLL:
+	case SCLK_BUS1_PLL_A:
+	case SCLK_BUS1_PLL_B:
+		return priv->sclk_bus1_pll_a;
+	default:
+		return 0;
+	}
+}
+
+static struct clk_ops exynos7420_clk_topc_ops = {
+	.get_periph_rate	= exynos7420_topc_get_periph_rate,
+};
+
+static int exynos7420_clk_topc_probe(struct udevice *dev)
+{
+	struct exynos7420_clk_topc_priv *priv = dev_get_priv(dev);
+	struct exynos7420_clk_cmu_topc *topc;
+	struct udevice *clk_dev;
+	unsigned long rate;
+	fdt_addr_t base;
+	int ret;
+
+	base = dev_get_addr(dev);
+	if (base == FDT_ADDR_T_NONE)
+		return -EINVAL;
+
+	topc = (struct exynos7420_clk_cmu_topc *)base;
+	priv->topc = topc;
+
+	ret = clk_get_by_index(dev, 0, &clk_dev);
+	if (ret >= 0)
+		priv->fin_freq = clk_get_rate(clk_dev);
+
+	rate = pll145x_get_rate(&topc->bus0_pll_con[0], priv->fin_freq);
+	if (readl(&topc->mux_sel[1]) & (1 << 16))
+		rate >>= 1;
+	rate /= DIVIDER(&topc->div[3], 0, 0xf);
+	priv->sclk_bus0_pll_a = rate;
+
+	rate = pll145x_get_rate(&topc->bus1_pll_con[0], priv->fin_freq) /
+			DIVIDER(&topc->div[3], 8, 0xf);
+	priv->sclk_bus1_pll_a = rate;
+
+	return 0;
+}
+
+static ulong exynos7420_top0_get_periph_rate(struct udevice *dev, int periph)
+{
+	struct exynos7420_clk_top0_priv *priv = dev_get_priv(dev);
+	struct exynos7420_clk_cmu_top0 *top0 = priv->top0;
+
+	switch (periph) {
+	case CLK_SCLK_UART2:
+		return priv->mout_top0_bus0_pll_half /
+			DIVIDER(&top0->div_peric[3], 8, 0xf);
+	default:
+		return 0;
+	}
+}
+
+static struct clk_ops exynos7420_clk_top0_ops = {
+	.get_periph_rate	= exynos7420_top0_get_periph_rate,
+};
+
+static int exynos7420_clk_top0_probe(struct udevice *dev)
+{
+	struct exynos7420_clk_top0_priv *priv;
+	struct exynos7420_clk_cmu_top0 *top0;
+	struct udevice *clk_dev;
+	fdt_addr_t base;
+	int ret;
+
+	priv = dev_get_priv(dev);
+	if (!priv)
+		return -EINVAL;
+
+	base = dev_get_addr(dev);
+	if (base == FDT_ADDR_T_NONE)
+		return -EINVAL;
+
+	top0 = (struct exynos7420_clk_cmu_top0 *)base;
+	priv->top0 = top0;
+
+	ret = clk_get_by_index(dev, 1, &clk_dev);
+	if (ret >= 0) {
+		priv->mout_top0_bus0_pll_half =
+			clk_get_periph_rate(clk_dev, ret);
+		if (readl(&top0->mux_sel[1]) & (1 << 16))
+			priv->mout_top0_bus0_pll_half >>= 1;
+	}
+
+	return 0;
+}
+
+static ulong exynos7420_peric1_get_periph_rate(struct udevice *dev, int periph)
+{
+	struct udevice *clk_dev;
+	unsigned int ret;
+	unsigned long freq = 0;
+
+	switch (periph) {
+	case SCLK_UART2:
+		ret = clk_get_by_index(dev, 3, &clk_dev);
+		if (ret < 0)
+			return ret;
+		freq = clk_get_periph_rate(clk_dev, ret);
+		break;
+	}
+
+	return freq;
+}
+
+static struct clk_ops exynos7420_clk_peric1_ops = {
+	.get_periph_rate	= exynos7420_peric1_get_periph_rate,
+};
+
+static const struct udevice_id exynos7420_clk_topc_compat[] = {
+	{ .compatible = "samsung,exynos7-clock-topc" },
+	{ }
+};
+
+U_BOOT_DRIVER(exynos7420_clk_topc) = {
+	.name = "exynos7420-clock-topc",
+	.id = UCLASS_CLK,
+	.of_match = exynos7420_clk_topc_compat,
+	.probe = exynos7420_clk_topc_probe,
+	.priv_auto_alloc_size = sizeof(struct exynos7420_clk_topc_priv),
+	.ops = &exynos7420_clk_topc_ops,
+	.flags = DM_FLAG_PRE_RELOC,
+};
+
+static const struct udevice_id exynos7420_clk_top0_compat[] = {
+	{ .compatible = "samsung,exynos7-clock-top0" },
+	{ }
+};
+
+U_BOOT_DRIVER(exynos7420_clk_top0) = {
+	.name = "exynos7420-clock-top0",
+	.id = UCLASS_CLK,
+	.of_match = exynos7420_clk_top0_compat,
+	.probe = exynos7420_clk_top0_probe,
+	.priv_auto_alloc_size = sizeof(struct exynos7420_clk_top0_priv),
+	.ops = &exynos7420_clk_top0_ops,
+	.flags = DM_FLAG_PRE_RELOC,
+};
+
+static const struct udevice_id exynos7420_clk_peric1_compat[] = {
+	{ .compatible = "samsung,exynos7-clock-peric1" },
+	{ }
+};
+
+U_BOOT_DRIVER(exynos7420_clk_peric1) = {
+	.name = "exynos7420-clock-peric1",
+	.id = UCLASS_CLK,
+	.of_match = exynos7420_clk_peric1_compat,
+	.ops = &exynos7420_clk_peric1_ops,
+	.flags = DM_FLAG_PRE_RELOC,
+};
diff --git a/drivers/clk/exynos/clk-pll.c b/drivers/clk/exynos/clk-pll.c
new file mode 100644
index 0000000..27220c5
--- /dev/null
+++ b/drivers/clk/exynos/clk-pll.c
@@ -0,0 +1,33 @@
+/*
+ * Exynos PLL helper functions for clock drivers.
+ * Copyright (C) 2016 Samsung Electronics
+ * Thomas Abraham <thomas.ab@samsung.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <div64.h>
+
+#define PLL145X_MDIV_SHIFT	16
+#define PLL145X_MDIV_MASK	0x3ff
+#define PLL145X_PDIV_SHIFT	8
+#define PLL145X_PDIV_MASK	0x3f
+#define PLL145X_SDIV_SHIFT	0
+#define PLL145X_SDIV_MASK	0x7
+
+unsigned long pll145x_get_rate(unsigned int *con1, unsigned long fin_freq)
+{
+	unsigned long pll_con1 = readl(con1);
+	unsigned long mdiv, sdiv, pdiv;
+	uint64_t fvco = fin_freq;
+
+	mdiv = (pll_con1 >> PLL145X_MDIV_SHIFT) & PLL145X_MDIV_MASK;
+	pdiv = (pll_con1 >> PLL145X_PDIV_SHIFT) & PLL145X_PDIV_MASK;
+	sdiv = (pll_con1 >> PLL145X_SDIV_SHIFT) & PLL145X_SDIV_MASK;
+
+	fvco *= mdiv;
+	do_div(fvco, (pdiv << sdiv));
+	return (unsigned long)fvco;
+}
diff --git a/drivers/clk/exynos/clk-pll.h b/drivers/clk/exynos/clk-pll.h
new file mode 100644
index 0000000..631d035
--- /dev/null
+++ b/drivers/clk/exynos/clk-pll.h
@@ -0,0 +1,9 @@
+/*
+ * Exynos PLL helper functions for clock drivers.
+ * Copyright (C) 2016 Samsung Electronics
+ * Thomas Abraham <thomas.ab@samsung.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+unsigned long pll145x_get_rate(unsigned int *con1, unsigned long fin_freq);