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_NO_PATH, /* Subchannels with no operational paths */
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

source code of linux/drivers/s390/cio/css.h