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 */
40 enum 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
45 struct 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
52 struct extended_cssid {
53 u8 version;
54 u8 cssid;
55 } __attribute__ ((packed));
56
57 struct 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
71 struct subchannel;
72 struct 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 */
85 struct 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
99 extern int css_driver_register(struct css_driver *);
100 extern void css_driver_unregister(struct css_driver *);
101
102 extern void css_sch_device_unregister(struct subchannel *);
103 extern int css_register_subchannel(struct subchannel *);
104 extern struct subchannel *css_alloc_subchannel(struct subchannel_id,
105 struct schib *schib);
106 extern struct subchannel *get_subchannel_by_schid(struct subchannel_id);
107 extern int css_init_done;
108 extern int max_ssid;
109 int for_each_subchannel_staged(int (*fn_known)(struct subchannel *, void *),
110 int (*fn_unknown)(struct subchannel_id,
111 void *), void *data);
112 extern int for_each_subchannel(int(*fn)(struct subchannel_id, void *), void *);
113 void css_update_ssd_info(struct subchannel *sch);
114
115 struct 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
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_cond(enum css_eval_cond, 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