/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _SMU_H
#define _SMU_H

/*
 * Definitions for talking to the SMU chip in newer G5 PowerMacs
 */
#ifdef __KERNEL__
#include <linux/list.h>
#endif
#include <linux/types.h>

/*
 * Known SMU commands
 *
 * Most of what is below comes from looking at the Open Firmware driver,
 * though this is still incomplete and could use better documentation here
 * or there...
 */


/*
 * Partition info commands
 *
 * These commands are used to retrieve the sdb-partition-XX datas from
 * the SMU. The length is always 2. First byte is the subcommand code
 * and second byte is the partition ID.
 *
 * The reply is 6 bytes:
 *
 *  - 0..1 : partition address
 *  - 2    : a byte containing the partition ID
 *  - 3    : length (maybe other bits are rest of header ?)
 *
 * The data must then be obtained with calls to another command:
 * SMU_CMD_MISC_ee_GET_DATABLOCK_REC (described below).
 */
#define SMU_CMD_PARTITION_COMMAND               0x3e
#define   SMU_CMD_PARTITION_LATEST              0x01
#define   SMU_CMD_PARTITION_BASE                0x02
#define   SMU_CMD_PARTITION_UPDATE              0x03


/*
 * Fan control
 *
 * This is a "mux" for fan control commands. The command seem to
 * act differently based on the number of arguments. With 1 byte
 * of argument, this seem to be queries for fans status, setpoint,
 * etc..., while with 0xe arguments, we will set the fans speeds.
 *
 * Queries (1 byte arg):
 * ---------------------
 *
 * arg=0x01: read RPM fans status
 * arg=0x02: read RPM fans setpoint
 * arg=0x11: read PWM fans status
 * arg=0x12: read PWM fans setpoint
 *
 * the "status" queries return the current speed while the "setpoint" ones
 * return the programmed/target speed. It _seems_ that the result is a bit
 * mask in the first byte of active/available fans, followed by 6 words (16
 * bits) containing the requested speed.
 *
 * Setpoint (14 bytes arg):
 * ------------------------
 *
 * first arg byte is 0 for RPM fans and 0x10 for PWM. Second arg byte is the
 * mask of fans affected by the command. Followed by 6 words containing the
 * setpoint value for selected fans in the mask (or 0 if mask value is 0)
 */
#define SMU_CMD_FAN_COMMAND                     0x4a


/*
 * Battery access
 *
 * Same command number as the PMU, could it be same syntax ?
 */
#define SMU_CMD_BATTERY_COMMAND                 0x6f
#define   SMU_CMD_GET_BATTERY_INFO              0x00

/*
 * Real time clock control
 *
 * This is a "mux", first data byte contains the "sub" command.
 * The "RTC" part of the SMU controls the date, time, powerup
 * timer, but also a PRAM
 *
 * Dates are in BCD format on 7 bytes:
 * [sec] [min] [hour] [weekday] [month day] [month] [year]
 * with month being 1 based and year minus 100
 */
#define SMU_CMD_RTC_COMMAND                     0x8e
#define   SMU_CMD_RTC_SET_PWRUP_TIMER           0x00 /* i: 7 bytes date */
#define   SMU_CMD_RTC_GET_PWRUP_TIMER           0x01 /* o: 7 bytes date */
#define   SMU_CMD_RTC_STOP_PWRUP_TIMER          0x02
#define   SMU_CMD_RTC_SET_PRAM_BYTE_ACC         0x20 /* i: 1 byte (address?) */
#define   SMU_CMD_RTC_SET_PRAM_AUTOINC          0x21 /* i: 1 byte (data?) */
#define   SMU_CMD_RTC_SET_PRAM_LO_BYTES         0x22 /* i: 10 bytes */
#define   SMU_CMD_RTC_SET_PRAM_HI_BYTES         0x23 /* i: 10 bytes */
#define   SMU_CMD_RTC_GET_PRAM_BYTE             0x28 /* i: 1 bytes (address?) */
#define   SMU_CMD_RTC_GET_PRAM_LO_BYTES         0x29 /* o: 10 bytes */
#define   SMU_CMD_RTC_GET_PRAM_HI_BYTES         0x2a /* o: 10 bytes */
#define   SMU_CMD_RTC_SET_DATETIME              0x80 /* i: 7 bytes date */
#define   SMU_CMD_RTC_GET_DATETIME              0x81 /* o: 7 bytes date */

 /*
  * i2c commands
  *
  * To issue an i2c command, first is to send a parameter block to
  * the SMU. This is a command of type 0x9a with 9 bytes of header
  * eventually followed by data for a write:
  *
  * 0: bus number (from device-tree usually, SMU has lots of busses !)
  * 1: transfer type/format (see below)
  * 2: device address. For combined and combined4 type transfers, this
  *    is the "write" version of the address (bit 0x01 cleared)
  * 3: subaddress length (0..3)
  * 4: subaddress byte 0 (or only byte for subaddress length 1)
  * 5: subaddress byte 1
  * 6: subaddress byte 2
  * 7: combined address (device address for combined mode data phase)
  * 8: data length
  *
  * The transfer types are the same good old Apple ones it seems,
  * that is:
  *   - 0x00: Simple transfer
  *   - 0x01: Subaddress transfer (addr write + data tx, no restart)
  *   - 0x02: Combined transfer (addr write + restart + data tx)
  *
  * This is then followed by actual data for a write.
  *
  * At this point, the OF driver seems to have a limitation on transfer
  * sizes of 0xd bytes on reads and 0x5 bytes on writes. I do not know
  * whether this is just an OF limit due to some temporary buffer size
  * or if this is an SMU imposed limit. This driver has the same limitation
  * for now as I use a 0x10 bytes temporary buffer as well
  *
  * Once that is completed, a response is expected from the SMU. This is
  * obtained via a command of type 0x9a with a length of 1 byte containing
  * 0 as the data byte. OF also fills the rest of the data buffer with 0xff's
  * though I can't tell yet if this is actually necessary. Once this command
  * is complete, at this point, all I can tell is what OF does. OF tests
  * byte 0 of the reply:
  *   - on read, 0xfe or 0xfc : bus is busy, wait (see below) or nak ?
  *   - on read, 0x00 or 0x01 : reply is in buffer (after the byte 0)
  *   - on write, < 0 -> failure (immediate exit)
  *   - else, OF just exists (without error, weird)
  *
  * So on read, there is this wait-for-busy thing when getting a 0xfc or
  * 0xfe result. OF does a loop of up to 64 retries, waiting 20ms and
  * doing the above again until either the retries expire or the result
  * is no longer 0xfe or 0xfc
  *
  * The Darwin I2C driver is less subtle though. On any non-success status
  * from the response command, it waits 5ms and tries again up to 20 times,
  * it doesn't differentiate between fatal errors or "busy" status.
  *
  * This driver provides an asynchronous paramblock based i2c command
  * interface to be used either directly by low level code or by a higher
  * level driver interfacing to the linux i2c layer. The current
  * implementation of this relies on working timers & timer interrupts
  * though, so be careful of calling context for now. This may be "fixed"
  * in the future by adding a polling facility.
  */
#define SMU_CMD_I2C_COMMAND                     0x9a
          /* transfer types */
#define   SMU_I2C_TRANSFER_SIMPLE       0x00
#define   SMU_I2C_TRANSFER_STDSUB       0x01
#define   SMU_I2C_TRANSFER_COMBINED     0x02

/*
 * Power supply control
 *
 * The "sub" command is an ASCII string in the data, the
 * data length is that of the string.
 *
 * The VSLEW command can be used to get or set the voltage slewing.
 *  - length 5 (only "VSLEW") : it returns "DONE" and 3 bytes of
 *    reply at data offset 6, 7 and 8.
 *  - length 8 ("VSLEWxyz") has 3 additional bytes appended, and is
 *    used to set the voltage slewing point. The SMU replies with "DONE"
 * I yet have to figure out their exact meaning of those 3 bytes in
 * both cases. They seem to be:
 *  x = processor mask
 *  y = op. point index
 *  z = processor freq. step index
 * I haven't yet deciphered result codes
 *
 */
#define SMU_CMD_POWER_COMMAND                   0xaa
#define   SMU_CMD_POWER_RESTART                 "RESTART"
#define   SMU_CMD_POWER_SHUTDOWN                "SHUTDOWN"
#define   SMU_CMD_POWER_VOLTAGE_SLEW            "VSLEW"

/*
 * Read ADC sensors
 *
 * This command takes one byte of parameter: the sensor ID (or "reg"
 * value in the device-tree) and returns a 16 bits value
 */
#define SMU_CMD_READ_ADC                        0xd8


/* Misc commands
 *
 * This command seem to be a grab bag of various things
 *
 * Parameters:
 *   1: subcommand
 */
#define SMU_CMD_MISC_df_COMMAND                 0xdf

/*
 * Sets "system ready" status
 *
 * I did not yet understand how it exactly works or what it does.
 *
 * Guessing from OF code, 0x02 activates the display backlight. Apple uses/used
 * the same codebase for all OF versions. On PowerBooks, this command would
 * enable the backlight. For the G5s, it only activates the front LED. However,
 * don't take this for granted.
 *
 * Parameters:
 *   2: status [0x00, 0x01 or 0x02]
 */
#define   SMU_CMD_MISC_df_SET_DISPLAY_LIT       0x02

/*
 * Sets mode of power switch.
 *
 * What this actually does is not yet known. Maybe it enables some interrupt.
 *
 * Parameters:
 *   2: enable power switch? [0x00 or 0x01]
 *   3 (optional): enable nmi? [0x00 or 0x01]
 *
 * Returns:
 *   If parameter 2 is 0x00 and parameter 3 is not specified, returns whether
 *   NMI is enabled. Otherwise unknown.
 */
#define   SMU_CMD_MISC_df_NMI_OPTION            0x04

/* Sets LED dimm offset.
 *
 * The front LED dimms itself during sleep. Its brightness (or, well, the PWM
 * frequency) depends on current time. Therefore, the SMU needs to know the
 * timezone.
 *
 * Parameters:
 *   2-8: unknown (BCD coding)
 */
#define   SMU_CMD_MISC_df_DIMM_OFFSET           0x99


/*
 * Version info commands
 *
 * Parameters:
 *   1 (optional): Specifies version part to retrieve
 *
 * Returns:
 *   Version value
 */
#define SMU_CMD_VERSION_COMMAND                 0xea
#define   SMU_VERSION_RUNNING                   0x00
#define   SMU_VERSION_BASE                      0x01
#define   SMU_VERSION_UPDATE                    0x02


/*
 * Switches
 *
 * These are switches whose status seems to be known to the SMU.
 *
 * Parameters:
 *   none
 *
 * Result:
 *   Switch bits (ORed, see below)
 */
#define SMU_CMD_SWITCHES                        0xdc

/* Switches bits */
#define SMU_SWITCH_CASE_CLOSED                  0x01
#define SMU_SWITCH_AC_POWER                     0x04
#define SMU_SWITCH_POWER_SWITCH                 0x08


/*
 * Misc commands
 *
 * This command seem to be a grab bag of various things
 *
 * SMU_CMD_MISC_ee_GET_DATABLOCK_REC is used, among others, to
 * transfer blocks of data from the SMU. So far, I've decrypted it's
 * usage to retrieve partition data. In order to do that, you have to
 * break your transfer in "chunks" since that command cannot transfer
 * more than a chunk at a time. The chunk size used by OF is 0xe bytes,
 * but it seems that the darwin driver will let you do 0x1e bytes if
 * your "PMU" version is >= 0x30. You can get the "PMU" version apparently
 * either in the last 16 bits of property "smu-version-pmu" or as the 16
 * bytes at offset 1 of "smu-version-info"
 *
 * For each chunk, the command takes 7 bytes of arguments:
 *  byte 0: subcommand code (0x02)
 *  byte 1: 0x04 (always, I don't know what it means, maybe the address
 *                space to use or some other nicety. It's hard coded in OF)
 *  byte 2..5: SMU address of the chunk (big endian 32 bits)
 *  byte 6: size to transfer (up to max chunk size)
 *
 * The data is returned directly
 */
#define SMU_CMD_MISC_ee_COMMAND                 0xee
#define   SMU_CMD_MISC_ee_GET_DATABLOCK_REC     0x02

/* Retrieves currently used watts.
 *
 * Parameters:
 *   1: 0x03 (Meaning unknown)
 */
#define   SMU_CMD_MISC_ee_GET_WATTS             0x03

#define   SMU_CMD_MISC_ee_LEDS_CTRL             0x04 /* i: 00 (00,01) [00] */
#define   SMU_CMD_MISC_ee_GET_DATA              0x05 /* i: 00 , o: ?? */


/*
 * Power related commands
 *
 * Parameters:
 *   1: subcommand
 */
#define SMU_CMD_POWER_EVENTS_COMMAND            0x8f

/* SMU_POWER_EVENTS subcommands */
enum {
        SMU_PWR_GET_POWERUP_EVENTS      = 0x00,
        SMU_PWR_SET_POWERUP_EVENTS      = 0x01,
        SMU_PWR_CLR_POWERUP_EVENTS      = 0x02,
        SMU_PWR_GET_WAKEUP_EVENTS       = 0x03,
        SMU_PWR_SET_WAKEUP_EVENTS       = 0x04,
        SMU_PWR_CLR_WAKEUP_EVENTS       = 0x05,

        /*
         * Get last shutdown cause
         *
         * Returns:
         *   1 byte (signed char): Last shutdown cause. Exact meaning unknown.
         */
        SMU_PWR_LAST_SHUTDOWN_CAUSE     = 0x07,

        /*
         * Sets or gets server ID. Meaning or use is unknown.
         *
         * Parameters:
         *   2 (optional): Set server ID (1 byte)
         *
         * Returns:
         *   1 byte (server ID?)
         */
        SMU_PWR_SERVER_ID               = 0x08,
};

/* Power events wakeup bits */
enum {
        SMU_PWR_WAKEUP_KEY              = 0x01, /* Wake on key press */
        SMU_PWR_WAKEUP_AC_INSERT        = 0x02, /* Wake on AC adapter plug */
        SMU_PWR_WAKEUP_AC_CHANGE        = 0x04,
        SMU_PWR_WAKEUP_LID_OPEN         = 0x08,
        SMU_PWR_WAKEUP_RING             = 0x10,
};


/*
 * - Kernel side interface -
 */

#ifdef __KERNEL__

/*
 * Asynchronous SMU commands
 *
 * Fill up this structure and submit it via smu_queue_command(),
 * and get notified by the optional done() callback, or because
 * status becomes != 1
 */

struct smu_cmd;

struct smu_cmd
{
        /* public */
        u8                      cmd;            /* command */
        int                     data_len;       /* data len */
        int                     reply_len;      /* reply len */
        void                    *data_buf;      /* data buffer */
        void                    *reply_buf;     /* reply buffer */
        int                     status;         /* command status */
        void                    (*done)(struct smu_cmd *cmd, void *misc);
        void                    *misc;

        /* private */
        struct list_head        link;
};

/*
 * Queues an SMU command, all fields have to be initialized
 */
extern int smu_queue_cmd(struct smu_cmd *cmd);

/*
 * Simple command wrapper. This structure embeds a small buffer
 * to ease sending simple SMU commands from the stack
 */
struct smu_simple_cmd
{
        struct smu_cmd  cmd;
        u8              buffer[16];
};

/*
 * Queues a simple command. All fields will be initialized by that
 * function
 */
extern int smu_queue_simple(struct smu_simple_cmd *scmd, u8 command,
                            unsigned int data_len,
                            void (*done)(struct smu_cmd *cmd, void *misc),
                            void *misc,
                            ...);

/*
 * Completion helper. Pass it to smu_queue_simple or as 'done'
 * member to smu_queue_cmd, it will call complete() on the struct
 * completion passed in the "misc" argument
 */
extern void smu_done_complete(struct smu_cmd *cmd, void *misc);

/*
 * Synchronous helpers. Will spin-wait for completion of a command
 */
extern void smu_spinwait_cmd(struct smu_cmd *cmd);

static inline void smu_spinwait_simple(struct smu_simple_cmd *scmd)
{
        smu_spinwait_cmd(&scmd->cmd);
}

/*
 * Poll routine to call if blocked with irqs off
 */
extern void smu_poll(void);


/*
 * Init routine, presence check....
 */
extern int smu_init(void);
extern int smu_present(void);
struct platform_device;
extern struct platform_device *smu_get_ofdev(void);


/*
 * Common command wrappers
 */
extern void smu_shutdown(void);
extern void smu_restart(void);
struct rtc_time;
extern int smu_get_rtc_time(struct rtc_time *time, int spinwait);
extern int smu_set_rtc_time(struct rtc_time *time, int spinwait);

/*
 * Kernel asynchronous i2c interface
 */

#define SMU_I2C_READ_MAX        0x1d
#define SMU_I2C_WRITE_MAX       0x15

/* SMU i2c header, exactly matches i2c header on wire */
struct smu_i2c_param
{
        u8      bus;            /* SMU bus ID (from device tree) */
        u8      type;           /* i2c transfer type */
        u8      devaddr;        /* device address (includes direction) */
        u8      sublen;         /* subaddress length */
        u8      subaddr[3];     /* subaddress */
        u8      caddr;          /* combined address, filled by SMU driver */
        u8      datalen;        /* length of transfer */
        u8      data[SMU_I2C_READ_MAX]; /* data */
};

struct smu_i2c_cmd
{
        /* public */
        struct smu_i2c_param    info;
        void                    (*done)(struct smu_i2c_cmd *cmd, void *misc);
        void                    *misc;
        int                     status; /* 1 = pending, 0 = ok, <0 = fail */

        /* private */
        struct smu_cmd          scmd;
        int                     read;
        int                     stage;
        int                     retries;
        u8                      pdata[32];
        struct list_head        link;
};

/*
 * Call this to queue an i2c command to the SMU. You must fill info,
 * including info.data for a write, done and misc.
 * For now, no polling interface is provided so you have to use completion
 * callback.
 */
extern int smu_queue_i2c(struct smu_i2c_cmd *cmd);


#endif /* __KERNEL__ */


/*
 * - SMU "sdb" partitions informations -
 */


/*
 * Partition header format
 */
struct smu_sdbp_header {
        __u8    id;
        __u8    len;
        __u8    version;
        __u8    flags;
};


 /*
 * demangle 16 and 32 bits integer in some SMU partitions
 * (currently, afaik, this concerns only the FVT partition
 * (0x12)
 */
#define SMU_U16_MIX(x)  le16_to_cpu(x)
#define SMU_U32_MIX(x)  ((((x) & 0xff00ff00u) >> 8)|(((x) & 0x00ff00ffu) << 8))


/* This is the definition of the SMU sdb-partition-0x12 table (called
 * CPU F/V/T operating points in Darwin). The definition for all those
 * SMU tables should be moved to some separate file
 */
#define SMU_SDB_FVT_ID                  0x12

struct smu_sdbp_fvt {
        __u32   sysclk;                 /* Base SysClk frequency in Hz for
                                         * this operating point. Value need to
                                         * be unmixed with SMU_U32_MIX()
                                         */
        __u8    pad;
        __u8    maxtemp;                /* Max temp. supported by this
                                         * operating point
                                         */

        __u16   volts[3];               /* CPU core voltage for the 3
                                         * PowerTune modes, a mode with
                                         * 0V = not supported. Value need
                                         * to be unmixed with SMU_U16_MIX()
                                         */
};

/* This partition contains voltage & current sensor calibration
 * informations
 */
#define SMU_SDB_CPUVCP_ID               0x21

struct smu_sdbp_cpuvcp {
        __u16   volt_scale;             /* u4.12 fixed point */
        __s16   volt_offset;            /* s4.12 fixed point */
        __u16   curr_scale;             /* u4.12 fixed point */
        __s16   curr_offset;            /* s4.12 fixed point */
        __s32   power_quads[3];         /* s4.28 fixed point */
};

/* This partition contains CPU thermal diode calibration
 */
#define SMU_SDB_CPUDIODE_ID             0x18

struct smu_sdbp_cpudiode {
        __u16   m_value;                /* u1.15 fixed point */
        __s16   b_value;                /* s10.6 fixed point */

};

/* This partition contains Slots power calibration
 */
#define SMU_SDB_SLOTSPOW_ID             0x78

struct smu_sdbp_slotspow {
        __u16   pow_scale;              /* u4.12 fixed point */
        __s16   pow_offset;             /* s4.12 fixed point */
};

/* This partition contains machine specific version information about
 * the sensor/control layout
 */
#define SMU_SDB_SENSORTREE_ID           0x25

struct smu_sdbp_sensortree {
        __u8    model_id;
        __u8    unknown[3];
};

/* This partition contains CPU thermal control PID informations. So far
 * only single CPU machines have been seen with an SMU, so we assume this
 * carries only informations for those
 */
#define SMU_SDB_CPUPIDDATA_ID           0x17

struct smu_sdbp_cpupiddata {
        __u8    unknown1;
        __u8    target_temp_delta;
        __u8    unknown2;
        __u8    history_len;
        __s16   power_adj;
        __u16   max_power;
        __s32   gp,gr,gd;
};


/* Other partitions without known structures */
#define SMU_SDB_DEBUG_SWITCHES_ID       0x05

#ifdef __KERNEL__
/*
 * This returns the pointer to an SMU "sdb" partition data or NULL
 * if not found. The data format is described below
 */
extern const struct smu_sdbp_header *smu_get_sdb_partition(int id,
                                        unsigned int *size);

/* Get "sdb" partition data from an SMU satellite */
extern struct smu_sdbp_header *smu_sat_get_sdb_partition(unsigned int sat_id,
                                        int id, unsigned int *size);


#endif /* __KERNEL__ */


/*
 * - Userland interface -
 */

/*
 * A given instance of the device can be configured for 2 different
 * things at the moment:
 *
 *  - sending SMU commands (default at open() time)
 *  - receiving SMU events (not yet implemented)
 *
 * Commands are written with write() of a command block. They can be
 * "driver" commands (for example to switch to event reception mode)
 * or real SMU commands. They are made of a header followed by command
 * data if any.
 *
 * For SMU commands (not for driver commands), you can then read() back
 * a reply. The reader will be blocked or not depending on how the device
 * file is opened. poll() isn't implemented yet. The reply will consist
 * of a header as well, followed by the reply data if any. You should
 * always provide a buffer large enough for the maximum reply data, I
 * recommand one page.
 *
 * It is illegal to send SMU commands through a file descriptor configured
 * for events reception
 *
 */
struct smu_user_cmd_hdr
{
        __u32           cmdtype;
#define SMU_CMDTYPE_SMU                 0       /* SMU command */
#define SMU_CMDTYPE_WANTS_EVENTS        1       /* switch fd to events mode */
#define SMU_CMDTYPE_GET_PARTITION       2       /* retrieve an sdb partition */

        __u8            cmd;                    /* SMU command byte */
        __u8            pad[3];                 /* padding */
        __u32           data_len;               /* Length of data following */
};

struct smu_user_reply_hdr
{
        __u32           status;                 /* Command status */
        __u32           reply_len;              /* Length of data follwing */
};

#endif /*  _SMU_H */