LXR linux/drivers/s390/cio/css.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _CSS_H
   3#define _CSS_H
   4
   5#include <linux/mutex.h>
   6#include <linux/wait.h>
   7#include <linux/workqueue.h>
   8#include <linux/device.h>
   9#include <linux/types.h>
  10
  11#include <asm/cio.h>
  12#include <asm/chpid.h>
  13#include <asm/schid.h>
  14
  15#include "cio.h"
  16
  17/*
  18 * path grouping stuff
  19 */
  20#define SPID_FUNC_SINGLE_PATH      0x00
  21#define SPID_FUNC_MULTI_PATH       0x80
  22#define SPID_FUNC_ESTABLISH        0x00
  23#define SPID_FUNC_RESIGN           0x40
  24#define SPID_FUNC_DISBAND          0x20
  25
  26#define SNID_STATE1_RESET          0
  27#define SNID_STATE1_UNGROUPED      2
  28#define SNID_STATE1_GROUPED        3
  29
  30#define SNID_STATE2_NOT_RESVD      0
  31#define SNID_STATE2_RESVD_ELSE     2
  32#define SNID_STATE2_RESVD_SELF     3
  33
  34#define SNID_STATE3_MULTI_PATH     1
  35#define SNID_STATE3_SINGLE_PATH    0
  36
  37/*
  38 * Conditions used to specify which subchannels need evaluation
  39 */
  40enum css_eval_cond {
  41        CSS_EVAL_UNREG,         /* unregistered subchannels */
  42        CSS_EVAL_NOT_ONLINE     /* sch without an online-device */
  43};
  44
  45struct path_state {
  46        __u8  state1 : 2;       /* path state value 1 */
  47        __u8  state2 : 2;       /* path state value 2 */
  48        __u8  state3 : 1;       /* path state value 3 */
  49        __u8  resvd  : 3;       /* reserved */
  50} __attribute__ ((packed));
  51
  52struct extended_cssid {
  53        u8 version;
  54        u8 cssid;
  55} __attribute__ ((packed));
  56
  57struct pgid {
  58        union {
  59                __u8 fc;        /* SPID function code */
  60                struct path_state ps;   /* SNID path state */
  61        } __attribute__ ((packed)) inf;
  62        union {
  63                __u32 cpu_addr  : 16;   /* CPU address */
  64                struct extended_cssid ext_cssid;
  65        } __attribute__ ((packed)) pgid_high;
  66        __u32 cpu_id    : 24;   /* CPU identification */
  67        __u32 cpu_model : 16;   /* CPU model */
  68        __u32 tod_high;         /* high word TOD clock */
  69} __attribute__ ((packed));
  70
  71struct subchannel;
  72struct chp_link;
  73/**
  74 * struct css_driver - device driver for subchannels
  75 * @subchannel_type: subchannel type supported by this driver
  76 * @drv: embedded device driver structure
  77 * @irq: called on interrupts
  78 * @chp_event: called for events affecting a channel path
  79 * @sch_event: called for events affecting the subchannel
  80 * @probe: function called on probe
  81 * @remove: function called on remove
  82 * @shutdown: called at device shutdown
  83 * @settle: wait for asynchronous work to finish
  84 */
  85struct css_driver {
  86        struct css_device_id *subchannel_type;
  87        struct device_driver drv;
  88        void (*irq)(struct subchannel *);
  89        int (*chp_event)(struct subchannel *, struct chp_link *, int);
  90        int (*sch_event)(struct subchannel *, int);
  91        int (*probe)(struct subchannel *);
  92        void (*remove)(struct subchannel *);
  93        void (*shutdown)(struct subchannel *);
  94        int (*settle)(void);
  95};
  96
  97#define to_cssdriver(n) container_of(n, struct css_driver, drv)
  98
  99extern int css_driver_register(struct css_driver *);
 100extern void css_driver_unregister(struct css_driver *);
 101
 102extern void css_sch_device_unregister(struct subchannel *);
 103extern int css_register_subchannel(struct subchannel *);
 104extern struct subchannel *css_alloc_subchannel(struct subchannel_id,
 105                                               struct schib *schib);
 106extern struct subchannel *get_subchannel_by_schid(struct subchannel_id);
 107extern int css_init_done;
 108extern int max_ssid;
 109int for_each_subchannel_staged(int (*fn_known)(struct subchannel *, void *),
 110                               int (*fn_unknown)(struct subchannel_id,
 111                               void *), void *data);
 112extern int for_each_subchannel(int(*fn)(struct subchannel_id, void *), void *);
 113void css_update_ssd_info(struct subchannel *sch);
 114
 115struct channel_subsystem {
 116        u8 cssid;
 117        u8 iid;
 118        bool id_valid; /* cssid,iid */
 119        struct channel_path *chps[__MAX_CHPID + 1];
 120        struct device device;
 121        struct pgid global_pgid;
 122        struct mutex mutex;
 123        /* channel measurement related */
 124        int cm_enabled;
 125        void *cub_addr1;
 126        void *cub_addr2;
 127        /* for orphaned ccw devices */
 128        struct subchannel *pseudo_subchannel;
 129};
 130#define to_css(dev) container_of(dev, struct channel_subsystem, device)
 131
 132extern struct channel_subsystem *channel_subsystems[];
 133
 134/* Dummy helper which needs to change once we support more than one css. */
 135static inline struct channel_subsystem *css_by_id(u8 cssid)
 136{
 137        return channel_subsystems[0];
 138}
 139
 140/* Dummy iterator which needs to change once we support more than one css. */
 141#define for_each_css(css)                                               \
 142        for ((css) = channel_subsystems[0]; (css); (css) = NULL)
 143
 144/* Helper functions to build lists for the slow path. */
 145void css_schedule_eval(struct subchannel_id schid);
 146void css_schedule_eval_all(void);
 147void css_schedule_eval_cond(enum css_eval_cond, unsigned long delay);
 148int css_complete_work(void);
 149
 150int sch_is_pseudo_sch(struct subchannel *);
 151struct schib;
 152int css_sch_is_valid(struct schib *);
 153
 154extern struct workqueue_struct *cio_work_q;
 155void css_wait_for_slow_path(void);
 156void css_sched_sch_todo(struct subchannel *sch, enum sch_todo todo);
 157#endif
 158