/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Copyright (c) 2006-2009 Simtec Electronics
 *      http://armlinux.simtec.co.uk/
 *      Ben Dooks <ben@simtec.co.uk>
 *
 * S3C CPU frequency scaling support - core support
 */

#include <plat/cpu-freq.h>

struct seq_file;

#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 after nOE/nWE */
        unsigned int    tcah;           /* Address hold after nCS */
        unsigned char   nwait_en;       /* nWait enabled for bank. */
};

/**
 * struct s3c2412_iobank_timing - io timings for PL092 (S3C2412) style IO
 * @idcy: The idle cycle time between transactions.
 * @wstrd: nCS release to end of read cycle.
 * @wstwr: nCS release to end of write cycle.
 * @wstoen: nCS assertion to nOE assertion time.
 * @wstwen: nCS assertion to nWE assertion time.
 * @wstbrd: Burst ready delay.
 * @smbidcyr: Register cache for smbidcyr value.
 * @smbwstrd: Register cache for smbwstrd value.
 * @smbwstwr: Register cache for smbwstwr value.
 * @smbwstoen: Register cache for smbwstoen value.
 * @smbwstwen: Register cache for smbwstwen value.
 * @smbwstbrd: Register cache for smbwstbrd value.
 *
 * Timing information for a IO bank on an S3C2412 or similar system which
 * uses a PL093 block.
 */
struct s3c2412_iobank_timing {
        unsigned int    idcy;
        unsigned int    wstrd;
        unsigned int    wstwr;
        unsigned int    wstoen;
        unsigned int    wstwen;
        unsigned int    wstbrd;

        /* register cache */
        unsigned char   smbidcyr;
        unsigned char   smbwstrd;
        unsigned char   smbwstwr;
        unsigned char   smbwstoen;
        unsigned char   smbwstwen;
        unsigned char   smbwstbrd;
};

union s3c_iobank {
        struct s3c2410_iobank_timing    *io_2410;
        struct s3c2412_iobank_timing    *io_2412;
};

/**
 * 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_config - current cpu frequency configuration
 * @freq: The current settings for the core clocks.
 * @max: Maxium settings, derived from core, board and user settings.
 * @pll: The PLL table entry for the current PLL settings.
 * @divs: The divisor settings for the core clocks.
 * @info: The current core driver information.
 * @board: The information for the board we are running on.
 * @lock_pll: Set if the PLL settings cannot be changed.
 *
 * This is for the core drivers that need to know information about
 * the current settings and values. It should not be needed by any
 * device drivers.
*/
struct s3c_cpufreq_config {
        struct s3c_freq         freq;
        struct s3c_freq         max;
        struct clk              *mpll;
        struct cpufreq_frequency_table pll;
        struct s3c_clkdivs      divs;
        struct s3c_cpufreq_info *info;  /* for core, not drivers */
        struct s3c_cpufreq_board *board;

        unsigned int    lock_pll:1;
};

/**
 * 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 achieve
 *      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.
 * @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 */

        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            (*debug_io_show)(struct seq_file *seq,
                                         struct s3c_cpufreq_config *cfg,
                                         union s3c_iobank *iob);

        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);

/* exports and utilities for debugfs */
extern struct s3c_cpufreq_config *s3c_cpufreq_getconfig(void);
extern struct s3c_iotimings *s3c_cpufreq_getiotimings(void);

#ifdef CONFIG_ARM_S3C24XX_CPUFREQ_DEBUGFS
#define s3c_cpufreq_debugfs_call(x) x
#else
#define s3c_cpufreq_debugfs_call(x) NULL
#endif

/* 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 void s3c2410_set_fvco(struct s3c_cpufreq_config *cfg);

#ifdef CONFIG_S3C2410_IOTIMING
extern void s3c2410_iotiming_debugfs(struct seq_file *seq,
                                     struct s3c_cpufreq_config *cfg,
                                     union s3c_iobank *iob);

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);
#else
#define s3c2410_iotiming_debugfs NULL
#define s3c2410_iotiming_calc NULL
#define s3c2410_iotiming_get NULL
#define s3c2410_iotiming_set NULL
#endif /* CONFIG_S3C2410_IOTIMING */

/* S3C2412 compatible routines */

#ifdef CONFIG_S3C2412_IOTIMING
extern void s3c2412_iotiming_debugfs(struct seq_file *seq,
                                     struct s3c_cpufreq_config *cfg,
                                     union s3c_iobank *iob);

extern int s3c2412_iotiming_get(struct s3c_cpufreq_config *cfg,
                                struct s3c_iotimings *timings);

extern int s3c2412_iotiming_calc(struct s3c_cpufreq_config *cfg,
                                 struct s3c_iotimings *iot);

extern void s3c2412_iotiming_set(struct s3c_cpufreq_config *cfg,
                                 struct s3c_iotimings *iot);
#else
#define s3c2412_iotiming_debugfs NULL
#define s3c2412_iotiming_calc NULL
#define s3c2412_iotiming_get NULL
#define s3c2412_iotiming_set NULL
#endif /* CONFIG_S3C2412_IOTIMING */

#ifdef CONFIG_ARM_S3C24XX_CPUFREQ_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_ARM_S3C24XX_CPUFREQ_DEBUG */

#ifdef CONFIG_ARM_S3C24XX_CPUFREQ_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_ARM_S3C24XX_CPUFREQ_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].driver_data = index;
                table[index].frequency = freq;
        }

        return index + 1;
}