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>

1 files changed, 183 insertions, 0 deletions

diff --git a/arch/arm/plat-s3c24xx/include/plat/cpu-freq-core.h b/arch/arm/plat-s3c24xx/include/plat/cpu-freq-core.h
new file mode 100644
index 000000000000..e078821b3605
--- /dev/null
+++ b/arch/arm/plat-s3c24xx/include/plat/cpu-freq-core.h
@@ -0,0 +1,183 @@
+/* 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;
+}