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. */
css_by_id(u8 cssid)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
167