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 struct path_state {
38 __u8 state1 : 2; /* path state value 1 */
39 __u8 state2 : 2; /* path state value 2 */
40 __u8 state3 : 1; /* path state value 3 */
41 __u8 resvd : 3; /* reserved */
42 } __attribute__ ((packed));
43
44 struct extended_cssid {
45 u8 version;
46 u8 cssid;
47 } __attribute__ ((packed));
48
49 struct pgid {
50 union {
51 __u8 fc; /* SPID function code */
52 struct path_state ps; /* SNID path state */
53 } __attribute__ ((packed)) inf;
54 union {
55 __u32 cpu_addr : 16; /* CPU address */
56 struct extended_cssid ext_cssid;
57 } __attribute__ ((packed)) pgid_high;
58 __u32 cpu_id : 24; /* CPU identification */
59 __u32 cpu_model : 16; /* CPU model */
60 __u32 tod_high; /* high word TOD clock */
61 } __attribute__ ((packed));
62
63 struct subchannel;
64 struct chp_link;
65 /**
66 * struct css_driver - device driver for subchannels
67 * @subchannel_type: subchannel type supported by this driver
68 * @drv: embedded device driver structure
69 * @irq: called on interrupts
70 * @chp_event: called for events affecting a channel path
71 * @sch_event: called for events affecting the subchannel
72 * @probe: function called on probe
73 * @remove: function called on remove
74 * @shutdown: called at device shutdown
75 * @prepare: prepare for pm state transition
76 * @complete: undo work done in @prepare
77 * @freeze: callback for freezing during hibernation snapshotting
78 * @thaw: undo work done in @freeze
79 * @restore: callback for restoring after hibernation
80 * @settle: wait for asynchronous work to finish
81 */
82 struct css_driver {
83 struct css_device_id *subchannel_type;
84 struct device_driver drv;
85 void (*irq)(struct subchannel *);
86 int (*chp_event)(struct subchannel *, struct chp_link *, int);
87 int (*sch_event)(struct subchannel *, int);
88 int (*probe)(struct subchannel *);
89 int (*remove)(struct subchannel *);
90 void (*shutdown)(struct subchannel *);
91 int (*prepare) (struct subchannel *);
92 void (*complete) (struct subchannel *);
93 int (*freeze)(struct subchannel *);
94 int (*thaw) (struct subchannel *);
95 int (*restore)(struct subchannel *);
96 int (*settle)(void);
97 };
98
99 #define to_cssdriver(n) container_of(n, struct css_driver, drv)
100
101 extern int css_driver_register(struct css_driver *);
102 extern void css_driver_unregister(struct css_driver *);
103
104 extern void css_sch_device_unregister(struct subchannel *);
105 extern int css_register_subchannel(struct subchannel *);
106 extern struct subchannel *css_alloc_subchannel(struct subchannel_id,
107 struct schib *schib);
108 extern struct subchannel *get_subchannel_by_schid(struct subchannel_id);
109 extern int css_init_done;
110 extern int max_ssid;
111 int for_each_subchannel_staged(int (*fn_known)(struct subchannel *, void *),
112 int (*fn_unknown)(struct subchannel_id,
113 void *), void *data);
114 extern int for_each_subchannel(int(*fn)(struct subchannel_id, void *), void *);
115 void css_update_ssd_info(struct subchannel *sch);
116
117 struct channel_subsystem {
118 int cssid;
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
132 extern struct channel_subsystem *channel_subsystems[];
133
134 /* Dummy helper which needs to change once we support more than one css. */
css_by_id(u8 cssid)135 static 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. */
145 void css_schedule_eval(struct subchannel_id schid);
146 void css_schedule_eval_all(void);
147 void css_schedule_eval_all_unreg(unsigned long delay);
148 int css_complete_work(void);
149
150 int sch_is_pseudo_sch(struct subchannel *);
151 struct schib;
152 int css_sch_is_valid(struct schib *);
153
154 extern struct workqueue_struct *cio_work_q;
155 void css_wait_for_slow_path(void);
156 void css_sched_sch_todo(struct subchannel *sch, enum sch_todo todo);
157 #endif
158