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  * Miscellaneous constants
  39  */
  40
  41 #define CSS_NUM_CUB_PAGES               2
  42 #define CSS_CUES_PER_PAGE               128
  43 #define CSS_NUM_ECUB_PAGES              4
  44 #define CSS_ECUES_PER_PAGE              64
  45
  46 /*
  47  * Conditions used to specify which subchannels need evaluation
  48  */
  49 enum css_eval_cond {
  50         CSS_EVAL_NO_PATH,               /* Subchannels with no operational paths */
  51         CSS_EVAL_NOT_ONLINE     /* sch without an online-device */
  52 };
  53
  54 struct path_state {
  55         __u8  state1 : 2;       /* path state value 1 */
  56         __u8  state2 : 2;       /* path state value 2 */
  57         __u8  state3 : 1;       /* path state value 3 */
  58         __u8  resvd  : 3;       /* reserved */
  59 } __attribute__ ((packed));
  60
  61 struct extended_cssid {
  62         u8 version;
  63         u8 cssid;
  64 } __attribute__ ((packed));
  65
  66 struct pgid {
  67         union {
  68                 __u8 fc;        /* SPID function code */
  69                 struct path_state ps;   /* SNID path state */
  70         } __attribute__ ((packed)) inf;
  71         union {
  72                 __u32 cpu_addr  : 16;   /* CPU address */
  73                 struct extended_cssid ext_cssid;
  74         } __attribute__ ((packed)) pgid_high;
  75         __u32 cpu_id    : 24;   /* CPU identification */
  76         __u32 cpu_model : 16;   /* CPU model */
  77         __u32 tod_high;         /* high word TOD clock */
  78 } __attribute__ ((packed));
  79
  80 struct subchannel;
  81 struct chp_link;
  82 /**
  83  * struct css_driver - device driver for subchannels
  84  * @subchannel_type: subchannel type supported by this driver
  85  * @drv: embedded device driver structure
  86  * @irq: called on interrupts
  87  * @chp_event: called for events affecting a channel path
  88  * @sch_event: called for events affecting the subchannel
  89  * @probe: function called on probe
  90  * @remove: function called on remove
  91  * @shutdown: called at device shutdown
  92  * @settle: wait for asynchronous work to finish
  93  */
  94 struct css_driver {
  95         struct css_device_id *subchannel_type;
  96         struct device_driver drv;
  97         void (*irq)(struct subchannel *);
  98         int (*chp_event)(struct subchannel *, struct chp_link *, int);
  99         int (*sch_event)(struct subchannel *, int);
 100         int (*probe)(struct subchannel *);
 101         void (*remove)(struct subchannel *);
 102         void (*shutdown)(struct subchannel *);
 103         int (*settle)(void);
 104 };
 105
 106 #define to_cssdriver(n) container_of_const(n, struct css_driver, drv)
 107
 108 extern int css_driver_register(struct css_driver *);
 109 extern void css_driver_unregister(struct css_driver *);
 110
 111 extern void css_sch_device_unregister(struct subchannel *);
 112 extern int css_register_subchannel(struct subchannel *);
 113 extern struct subchannel *css_alloc_subchannel(struct subchannel_id,
 114                                                struct schib *schib);
 115 extern struct subchannel *get_subchannel_by_schid(struct subchannel_id);
 116 extern int css_init_done;
 117 extern int max_ssid;
 118 int for_each_subchannel_staged(int (*fn_known)(struct subchannel *, void *),
 119                                int (*fn_unknown)(struct subchannel_id,
 120                                void *), void *data);
 121 extern int for_each_subchannel(int(*fn)(struct subchannel_id, void *), void *);
 122 void css_update_ssd_info(struct subchannel *sch);
 123
 124 struct channel_subsystem {
 125         u8 cssid;
 126         u8 iid;
 127         bool id_valid; /* cssid,iid */
 128         struct channel_path *chps[__MAX_CHPID + 1];
 129         struct device device;
 130         struct pgid global_pgid;
 131         struct mutex mutex;
 132         /* channel measurement related */
 133         int cm_enabled;
 134         void *cub[CSS_NUM_CUB_PAGES];
 135         void *ecub[CSS_NUM_ECUB_PAGES];
 136         /* for orphaned ccw devices */
 137         struct subchannel *pseudo_subchannel;
 138 };
 139 #define to_css(dev) container_of(dev, struct channel_subsystem, device)
 140
 141 extern struct channel_subsystem *channel_subsystems[];
 142
 143 /* Dummy helper which needs to change once we support more than one css. */
 144 static inline struct channel_subsystem *css_by_id(u8 cssid)
 145 {
 146         return channel_subsystems[0];
 147 }
 148
 149 /* Dummy iterator which needs to change once we support more than one css. */
 150 #define for_each_css(css)                                               \
 151         for ((css) = channel_subsystems[0]; (css); (css) = NULL)
 152
 153 /* Helper functions to build lists for the slow path. */
 154 void css_schedule_eval(struct subchannel_id schid);
 155 void css_schedule_eval_all(void);
 156 void css_schedule_eval_cond(enum css_eval_cond, unsigned long delay);
 157 int css_complete_work(void);
 158
 159 int sch_is_pseudo_sch(struct subchannel *);
 160 struct schib;
 161 int css_sch_is_valid(struct schib *);
 162
 163 extern struct workqueue_struct *cio_work_q;
 164 void css_wait_for_slow_path(void);
 165 void css_sched_sch_todo(struct subchannel *sch, enum sch_todo todo);
 166 #endif