[ARM] tegra: Add clock support

v2: fixes from Russell King:
	- include linux/io.h instead of asm/io.h
	- fix whitespace in Kconfig
	- Use spin_lock_init to initialize lock
	- Return -ENOSYS instead of BUG for unimplemented clock ops
	- Use proper return values in tegra2 clock ops
    additional changes:
	- Rename some clocks to match dev_ids
	- add rate propagation
	- add debugfs entries
	- add support for clock listed in clk_lookup under multiple dev_ids
v3:
	- Replace per-clock locking with global clock lock
	- Autodetect clock state on init
	- Let clock dividers pick next lower possible frequency
	- Add support for clock init tables
	- Minor bug fixes
	- Fix checkpatch issues
Signed-off-by: Colin Cross <ccross@android.com>

arch/arm/Kconfig

@@ -568,6 +568,7 @@ config ARCH_TEGRA
 	select GENERIC_CLOCKEVENTS
 	select GENERIC_GPIO
 	select HAVE_CLK
+	select COMMON_CLKDEV
 	select ARCH_HAS_BARRIERS if CACHE_L2X0
 	help
 	  This enables support for NVIDIA Tegra based systems (Tegra APX,

arch/arm/mach-tegra/Makefile

 obj-y                                   += common.o
 obj-y                                   += io.o
 obj-y                                   += irq.o
+obj-y                                   += clock.o
+obj-$(CONFIG_ARCH_TEGRA_2x_SOC)         += tegra2_clocks.o

arch/arm/mach-tegra/clock.h

+/*
+ * arch/arm/mach-tegra/include/mach/clock.h
+ *
+ * Copyright (C) 2010 Google, Inc.
+ *
+ * Author:
+ *	Colin Cross <ccross@google.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef __MACH_TEGRA_CLOCK_H
+#define __MACH_TEGRA_CLOCK_H
+
+#include <linux/list.h>
+#include <asm/clkdev.h>
+
+#define DIV_BUS			(1 << 0)
+#define DIV_U71			(1 << 1)
+#define DIV_U71_FIXED		(1 << 2)
+#define DIV_2			(1 << 3)
+#define PLL_FIXED		(1 << 4)
+#define PLL_HAS_CPCON		(1 << 5)
+#define MUX			(1 << 6)
+#define PLLD			(1 << 7)
+#define PERIPH_NO_RESET		(1 << 8)
+#define PERIPH_NO_ENB		(1 << 9)
+#define PERIPH_EMC_ENB		(1 << 10)
+#define PERIPH_MANUAL_RESET	(1 << 11)
+#define PLL_ALT_MISC_REG	(1 << 12)
+#define ENABLE_ON_INIT		(1 << 28)
+
+struct clk;
+
+struct clk_mux_sel {
+	struct clk	*input;
+	u32		value;
+};
+
+struct clk_pll_table {
+	unsigned long	input_rate;
+	unsigned long	output_rate;
+	u16		n;
+	u16		m;
+	u8		p;
+	u8		cpcon;
+};
+
+struct clk_ops {
+	void		(*init)(struct clk *);
+	int		(*enable)(struct clk *);
+	void		(*disable)(struct clk *);
+	void		(*recalc)(struct clk *);
+	int		(*set_parent)(struct clk *, struct clk *);
+	int		(*set_rate)(struct clk *, unsigned long);
+	unsigned long	(*get_rate)(struct clk *);
+	long		(*round_rate)(struct clk *, unsigned long);
+	unsigned long	(*recalculate_rate)(struct clk *);
+};
+
+enum clk_state {
+	UNINITIALIZED = 0,
+	ON,
+	OFF,
+};
+
+struct clk {
+	/* node for master clocks list */
+	struct list_head		node;
+	struct list_head		children;	/* list of children */
+	struct list_head		sibling;	/* node for children */
+#ifdef CONFIG_DEBUG_FS
+	struct dentry			*dent;
+	struct dentry			*parent_dent;
+#endif
+	struct clk_ops			*ops;
+	struct clk			*parent;
+	struct clk_lookup		lookup;
+	unsigned long			rate;
+	u32				flags;
+	u32				refcnt;
+	const char			*name;
+	u32				reg;
+	u32				reg_shift;
+	unsigned int			clk_num;
+	enum clk_state			state;
+#ifdef CONFIG_DEBUG_FS
+	bool				set;
+#endif
+
+	/* PLL */
+	unsigned long			input_min;
+	unsigned long			input_max;
+	unsigned long			cf_min;
+	unsigned long			cf_max;
+	unsigned long			vco_min;
+	unsigned long			vco_max;
+	u32				m;
+	u32				n;
+	u32				p;
+	u32				cpcon;
+	const struct clk_pll_table	*pll_table;
+
+	/* DIV */
+	u32				div;
+	u32				mul;
+
+	/* MUX */
+	const struct clk_mux_sel	*inputs;
+	u32				sel;
+	u32				reg_mask;
+};
+
+
+struct clk_duplicate {
+	const char *name;
+	struct clk_lookup lookup;
+};
+
+struct tegra_clk_init_table {
+	const char *name;
+	const char *parent;
+	unsigned long rate;
+	bool enabled;
+};
+
+void tegra2_init_clocks(void);
+void tegra2_periph_reset_deassert(struct clk *c);
+void tegra2_periph_reset_assert(struct clk *c);
+void clk_init(struct clk *clk);
+struct clk *tegra_get_clock_by_name(const char *name);
+unsigned long clk_measure_input_freq(void);
+void clk_disable_locked(struct clk *c);
+int clk_enable_locked(struct clk *c);
+int clk_set_parent_locked(struct clk *c, struct clk *parent);
+int clk_reparent(struct clk *c, struct clk *parent);
+void tegra_clk_init_from_table(struct tegra_clk_init_table *table);
+
+#endif

arch/arm/mach-tegra/common.c

@@ -25,6 +25,21 @@
 #include <mach/iomap.h>
 
 #include "board.h"
+#include "clock.h"
+
+static __initdata struct tegra_clk_init_table common_clk_init_table[] = {
+	/* name		parent		rate		enabled */
+	{ "clk_m",	NULL,		0,		true },
+	{ "pll_p",	"clk_m",	216000000,	true },
+	{ "pll_p_out1",	"pll_p",	28800000,	true },
+	{ "pll_p_out2",	"pll_p",	48000000,	true },
+	{ "pll_p_out3",	"pll_p",	72000000,	true },
+	{ "pll_p_out4",	"pll_p",	108000000,	true },
+	{ "sys",	"pll_p_out4",	108000000,	true },
+	{ "hclk",	"sys",		108000000,	true },
+	{ "pclk",	"hclk",		54000000,	true },
+	{ NULL,		NULL,		0,		0},
+};
 
 void __init tegra_init_cache(void)
 {
@@ -40,5 +55,7 @@ void __init tegra_init_cache(void)
 
 void __init tegra_common_init(void)
 {
+	tegra_init_clock();
+	tegra_clk_init_from_table(common_clk_init_table);
 	tegra_init_cache();
 }

arch/arm/mach-tegra/include/mach/clk.h

+/*
+ * arch/arm/mach-tegra/include/mach/clk.h
+ *
+ * Copyright (C) 2010 Google, Inc.
+ *
+ * Author:
+ *	Erik Gilling <konkers@google.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef __MACH_CLK_H
+#define __MACH_CLK_H
+
+void tegra_periph_reset_deassert(struct clk *c);
+void tegra_periph_reset_assert(struct clk *c);
+
+#endif

arch/arm/mach-tegra/include/mach/clkdev.h

+/*
+ * arch/arm/mach-tegra/include/mach/clkdev.h
+ *
+ * Copyright (C) 2010 Google, Inc.
+ *
+ * Author:
+ *	Colin Cross <ccross@google.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef __MACH_CLKDEV_H
+#define __MACH_CLKDEV_H
+
+static inline int __clk_get(struct clk *clk)
+{
+	return 1;
+}
+
+static inline void __clk_put(struct clk *clk)
+{
+}
+
+#endif