root/drivers/misc/ibmasm/ibmasm.h
/* SPDX-License-Identifier: GPL-2.0-or-later */

/*
 * IBM ASM Service Processor Device Driver
 *
 * Copyright (C) IBM Corporation, 2004
 *
 * Author: Max Asböck <amax@us.ibm.com>
 */

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/list.h>
#include <linux/wait.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/kref.h>
#include <linux/device.h>
#include <linux/input.h>
#include <linux/time64.h>

/* Driver identification */
#define DRIVER_NAME     "ibmasm"
#define DRIVER_VERSION  "1.0"
#define DRIVER_AUTHOR   "Max Asbock <masbock@us.ibm.com>, Vernon Mauery <vernux@us.ibm.com>"
#define DRIVER_DESC     "IBM ASM Service Processor Driver"

#define err(msg) printk(KERN_ERR "%s: " msg "\n", DRIVER_NAME)
#define info(msg) printk(KERN_INFO "%s: " msg "\n", DRIVER_NAME)

extern int ibmasm_debug;
#define dbg(STR, ARGS...)                                       \
        do {                                                    \
                if (ibmasm_debug)                               \
                        printk(KERN_DEBUG STR , ##ARGS);        \
        } while (0)

static inline char *get_timestamp(char *buf)
{
        struct timespec64 now;

        ktime_get_real_ts64(&now);
        sprintf(buf, "%llu.%.08lu", (long long)now.tv_sec,
                                now.tv_nsec / NSEC_PER_USEC);
        return buf;
}

#define IBMASM_CMD_PENDING      0
#define IBMASM_CMD_COMPLETE     1
#define IBMASM_CMD_FAILED       2

#define IBMASM_CMD_TIMEOUT_NORMAL       45
#define IBMASM_CMD_TIMEOUT_EXTRA        240

#define IBMASM_CMD_MAX_BUFFER_SIZE      0x8000

#define REVERSE_HEARTBEAT_TIMEOUT       120

#define HEARTBEAT_BUFFER_SIZE           0x400

#ifdef IA64
#define IBMASM_DRIVER_VPD "Lin64 6.08      "
#else
#define IBMASM_DRIVER_VPD "Lin32 6.08      "
#endif

#define SYSTEM_STATE_OS_UP      5
#define SYSTEM_STATE_OS_DOWN    4

#define IBMASM_NAME_SIZE        16

#define IBMASM_NUM_EVENTS       10
#define IBMASM_EVENT_MAX_SIZE   2048u


struct command {
        struct list_head        queue_node;
        wait_queue_head_t       wait;
        unsigned char           *buffer;
        size_t                  buffer_size;
        int                     status;
        struct kref             kref;
        spinlock_t              *lock;
};
#define to_command(c) container_of(c, struct command, kref)

void ibmasm_free_command(struct kref *kref);
static inline void command_put(struct command *cmd)
{
        unsigned long flags;
        spinlock_t *lock = cmd->lock;

        spin_lock_irqsave(lock, flags);
        kref_put(&cmd->kref, ibmasm_free_command);
        spin_unlock_irqrestore(lock, flags);
}

static inline void command_get(struct command *cmd)
{
        kref_get(&cmd->kref);
}


struct ibmasm_event {
        unsigned int    serial_number;
        unsigned int    data_size;
        unsigned char   data[IBMASM_EVENT_MAX_SIZE];
};

struct event_buffer {
        struct ibmasm_event     events[IBMASM_NUM_EVENTS];
        unsigned int            next_serial_number;
        unsigned int            next_index;
        struct list_head        readers;
};

struct event_reader {
        int                     cancelled;
        unsigned int            next_serial_number;
        wait_queue_head_t       wait;
        struct list_head        node;
        unsigned int            data_size;
        unsigned char           data[IBMASM_EVENT_MAX_SIZE];
};

struct reverse_heartbeat {
        wait_queue_head_t       wait;
        unsigned int            stopped;
};

struct ibmasm_remote {
        struct input_dev *keybd_dev;
        struct input_dev *mouse_dev;
};

struct service_processor {
        struct list_head        node;
        spinlock_t              lock;
        void __iomem            *base_address;
        unsigned int            irq;
        struct command          *current_command;
        struct command          *heartbeat;
        struct list_head        command_queue;
        struct event_buffer     *event_buffer;
        char                    dirname[IBMASM_NAME_SIZE];
        char                    devname[IBMASM_NAME_SIZE];
        unsigned int            number;
        struct ibmasm_remote    remote;
        int                     serial_line;
        struct device           *dev;
};

/* command processing */
struct command *ibmasm_new_command(struct service_processor *sp, size_t buffer_size);
void ibmasm_exec_command(struct service_processor *sp, struct command *cmd);
void ibmasm_wait_for_response(struct command *cmd, int timeout);
void ibmasm_receive_command_response(struct service_processor *sp, void *response,  size_t size);

/* event processing */
int ibmasm_event_buffer_init(struct service_processor *sp);
void ibmasm_event_buffer_exit(struct service_processor *sp);
void ibmasm_receive_event(struct service_processor *sp, void *data,  unsigned int data_size);
void ibmasm_event_reader_register(struct service_processor *sp, struct event_reader *reader);
void ibmasm_event_reader_unregister(struct service_processor *sp, struct event_reader *reader);
int ibmasm_get_next_event(struct service_processor *sp, struct event_reader *reader);
void ibmasm_cancel_next_event(struct event_reader *reader);

/* heartbeat - from SP to OS */
void ibmasm_register_panic_notifier(void);
void ibmasm_unregister_panic_notifier(void);
int ibmasm_heartbeat_init(struct service_processor *sp);
void ibmasm_heartbeat_exit(struct service_processor *sp);
void ibmasm_receive_heartbeat(struct service_processor *sp,  void *message, size_t size);

/* reverse heartbeat - from OS to SP */
void ibmasm_init_reverse_heartbeat(struct service_processor *sp, struct reverse_heartbeat *rhb);
int ibmasm_start_reverse_heartbeat(struct service_processor *sp, struct reverse_heartbeat *rhb);
void ibmasm_stop_reverse_heartbeat(struct reverse_heartbeat *rhb);

/* dot commands */
void ibmasm_receive_message(struct service_processor *sp, void *data, int data_size);
int ibmasm_send_driver_vpd(struct service_processor *sp);
int ibmasm_send_os_state(struct service_processor *sp, int os_state);

/* low level message processing */
int ibmasm_send_i2o_message(struct service_processor *sp);
irqreturn_t ibmasm_interrupt_handler(int irq, void * dev_id);

/* remote console */
void ibmasm_handle_mouse_interrupt(struct service_processor *sp);
int ibmasm_init_remote_input_dev(struct service_processor *sp);
void ibmasm_free_remote_input_dev(struct service_processor *sp);

/* file system */
int ibmasmfs_register(void);
void ibmasmfs_unregister(void);
void ibmasmfs_add_sp(struct service_processor *sp);

/* uart */
#if IS_ENABLED(CONFIG_SERIAL_8250)
void ibmasm_register_uart(struct service_processor *sp);
void ibmasm_unregister_uart(struct service_processor *sp);
#else
#define ibmasm_register_uart(sp)        do { } while(0)
#define ibmasm_unregister_uart(sp)      do { } while(0)
#endif