ARM: S3C24XX: CPUFREQ: Add core support.

Add the core of the support for enabling the CPUFreq driver on
all S3C24XX based systems.
Signed-off-by: Ben Dooks <ben@simtec.co.uk>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>

arch/arm/plat-s3c24xx/Makefile

@@ -20,6 +20,8 @@ obj-y				+= gpiolib.o
 obj-y				+= clock.o
 obj-$(CONFIG_S3C24XX_DCLK)	+= clock-dclk.o
 
+obj-$(CONFIG_CPU_FREQ_S3C24XX)	+= cpu-freq.o
+
 # Architecture dependant builds
 
 obj-$(CONFIG_CPU_S3C244X)	+= s3c244x.o

arch/arm/plat-s3c24xx/include/plat/cpu-freq-core.h

+/* arch/arm/plat-s3c/include/plat/cpu-freq.h
+ *
+ * Copyright (c) 2006,2007,2009 Simtec Electronics
+ *	http://armlinux.simtec.co.uk/
+ *	Ben Dooks <ben@simtec.co.uk>
+ *
+ * S3C CPU frequency scaling support - core support
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+#include <plat/cpu-freq.h>
+
+#define MAX_BANKS (8)
+#define S3C2412_MAX_IO	(8)
+
+/**
+ * struct s3c2410_iobank_timing - IO bank timings for S3C2410 style timings
+ * @bankcon: The cached version of settings in this structure.
+ * @tacp:
+ * @tacs: Time from address valid to nCS asserted.
+ * @tcos: Time from nCS asserted to nOE or nWE asserted.
+ * @tacc: Time that nOE or nWE is asserted.
+ * @tcoh: Time nCS is held after nOE or nWE are released.
+ * @tcah: Time address is held for after
+ * @nwait_en: Whether nWAIT is enabled for this bank.
+ *
+ * This structure represents the IO timings for a S3C2410 style IO bank
+ * used by the CPU frequency support if it needs to change the settings
+ * of the IO.
+ */
+struct s3c2410_iobank_timing {
+	unsigned long	bankcon;
+	unsigned int	tacp;
+	unsigned int	tacs;
+	unsigned int	tcos;
+	unsigned int	tacc;
+	unsigned int	tcoh;		/* nCS hold afrer nOE/nWE */
+	unsigned int	tcah;		/* Address hold after nCS */
+	unsigned char	nwait_en;	/* nWait enabled for bank. */
+};
+
+union s3c_iobank {
+	  struct s3c2410_iobank_timing	*io_2410;
+};
+
+/**
+ * struct s3c_iotimings - Chip IO timings holder
+ * @bank: The timings for each IO bank.
+ */
+struct s3c_iotimings {
+	union s3c_iobank	bank[MAX_BANKS];
+};
+
+/**
+ * struct s3c_plltab - PLL table information.
+ * @vals: List of PLL values.
+ * @size: Size of the PLL table @vals.
+ */
+struct s3c_plltab {
+	struct s3c_pllval	*vals;
+	int			 size;
+};
+
+/**
+ * struct s3c_cpufreq_info - Information for the CPU frequency driver.
+ * @name: The name of this implementation.
+ * @max: The maximum frequencies for the system.
+ * @latency: Transition latency to give to cpufreq.
+ * @locktime_m: The lock-time in uS for the MPLL.
+ * @locktime_u: The lock-time in uS for the UPLL.
+ * @locttime_bits: The number of bits each LOCKTIME field.
+ * @need_pll: Set if this driver needs to change the PLL values to acheive
+ *	any frequency changes. This is really only need by devices like the
+ *	S3C2410 where there is no or limited divider between the PLL and the
+ *	ARMCLK.
+ * @resume_clocks: Update the clocks on resume.
+ * @get_iotiming: Get the current IO timing data, mainly for use at start.
+ * @set_iotiming: Update the IO timings from the cached copies calculated
+ *	from the @calc_iotiming entry when changing the frequency.
+ * @calc_iotiming: Calculate and update the cached copies of the IO timings
+ *	from the newly calculated frequencies.
+ * @calc_freqtable: Calculate (fill in) the given frequency table from the
+ *	current frequency configuration. If the table passed in is NULL,
+ *	then the return is the number of elements to be filled for allocation
+ *	of the table.
+ * @set_refresh: Set the memory refresh configuration.
+ * @set_fvco: Set the PLL frequencies.
+ * @set_divs: Update the clock divisors.
+ * @calc_divs: Calculate the clock divisors.
+ */
+struct s3c_cpufreq_info {
+	const char		*name;
+	struct s3c_freq		max;
+
+	unsigned int		latency;
+
+	unsigned int		locktime_m;
+	unsigned int		locktime_u;
+	unsigned char		locktime_bits;
+
+	unsigned int		need_pll:1;
+
+	/* driver routines */
+
+	void		(*resume_clocks)(void);
+
+	int		(*get_iotiming)(struct s3c_cpufreq_config *cfg,
+					struct s3c_iotimings *timings);
+
+	void		(*set_iotiming)(struct s3c_cpufreq_config *cfg,
+					struct s3c_iotimings *timings);
+
+	int		(*calc_iotiming)(struct s3c_cpufreq_config *cfg,
+					 struct s3c_iotimings *timings);
+
+	int		(*calc_freqtable)(struct s3c_cpufreq_config *cfg,
+					  struct cpufreq_frequency_table *t,
+					  size_t table_size);
+
+	void		(*set_refresh)(struct s3c_cpufreq_config *cfg);
+	void		(*set_fvco)(struct s3c_cpufreq_config *cfg);
+	void		(*set_divs)(struct s3c_cpufreq_config *cfg);
+	int		(*calc_divs)(struct s3c_cpufreq_config *cfg);
+};
+
+extern int s3c_cpufreq_register(struct s3c_cpufreq_info *info);
+
+extern int s3c_plltab_register(struct cpufreq_frequency_table *plls, unsigned int plls_no);
+
+/* Useful utility functions. */
+
+extern struct clk *s3c_cpufreq_clk_get(struct device *, const char *);
+
+/* S3C2410 and compatible exported functions */
+
+extern void s3c2410_cpufreq_setrefresh(struct s3c_cpufreq_config *cfg);
+
+extern int s3c2410_iotiming_calc(struct s3c_cpufreq_config *cfg,
+				 struct s3c_iotimings *iot);
+
+extern int s3c2410_iotiming_get(struct s3c_cpufreq_config *cfg,
+				struct s3c_iotimings *timings);
+
+extern void s3c2410_iotiming_set(struct s3c_cpufreq_config *cfg,
+				 struct s3c_iotimings *iot);
+
+extern void s3c2410_set_fvco(struct s3c_cpufreq_config *cfg);
+
+#ifdef CONFIG_CPU_FREQ_S3C24XX_DEBUG
+#define s3c_freq_dbg(x...) printk(KERN_INFO x)
+#else
+#define s3c_freq_dbg(x...) do { if (0) printk(x); } while (0)
+#endif /* CONFIG_CPU_FREQ_S3C24XX_DEBUG */
+
+#ifdef CONFIG_CPU_FREQ_S3C24XX_IODEBUG
+#define s3c_freq_iodbg(x...) printk(KERN_INFO x)
+#else
+#define s3c_freq_iodbg(x...) do { if (0) printk(x); } while (0)
+#endif /* CONFIG_CPU_FREQ_S3C24XX_IODEBUG */
+
+static inline int s3c_cpufreq_addfreq(struct cpufreq_frequency_table *table,
+				      int index, size_t table_size,
+				      unsigned int freq)
+{
+	if (index < 0)
+		return index;
+
+	if (table) {
+		if (index >= table_size)
+			return -ENOMEM;
+
+		s3c_freq_dbg("%s: { %d = %u kHz }\n",
+			     __func__, index, freq);
+
+		table[index].index = index;
+		table[index].frequency = freq;
+	}
+
+	return index + 1;
+}