xref: /linux/drivers/s390/cio/css.h (revision c79c3c34f75d72a066e292b10aa50fc758c97c89)
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  * @settle: wait for asynchronous work to finish
76  */
77 struct css_driver {
78 	struct css_device_id *subchannel_type;
79 	struct device_driver drv;
80 	void (*irq)(struct subchannel *);
81 	int (*chp_event)(struct subchannel *, struct chp_link *, int);
82 	int (*sch_event)(struct subchannel *, int);
83 	int (*probe)(struct subchannel *);
84 	int (*remove)(struct subchannel *);
85 	void (*shutdown)(struct subchannel *);
86 	int (*settle)(void);
87 };
88 
89 #define to_cssdriver(n) container_of(n, struct css_driver, drv)
90 
91 extern int css_driver_register(struct css_driver *);
92 extern void css_driver_unregister(struct css_driver *);
93 
94 extern void css_sch_device_unregister(struct subchannel *);
95 extern int css_register_subchannel(struct subchannel *);
96 extern struct subchannel *css_alloc_subchannel(struct subchannel_id,
97 					       struct schib *schib);
98 extern struct subchannel *get_subchannel_by_schid(struct subchannel_id);
99 extern int css_init_done;
100 extern int max_ssid;
101 int for_each_subchannel_staged(int (*fn_known)(struct subchannel *, void *),
102 			       int (*fn_unknown)(struct subchannel_id,
103 			       void *), void *data);
104 extern int for_each_subchannel(int(*fn)(struct subchannel_id, void *), void *);
105 void css_update_ssd_info(struct subchannel *sch);
106 
107 struct channel_subsystem {
108 	u8 cssid;
109 	u8 iid;
110 	bool id_valid; /* cssid,iid */
111 	struct channel_path *chps[__MAX_CHPID + 1];
112 	struct device device;
113 	struct pgid global_pgid;
114 	struct mutex mutex;
115 	/* channel measurement related */
116 	int cm_enabled;
117 	void *cub_addr1;
118 	void *cub_addr2;
119 	/* for orphaned ccw devices */
120 	struct subchannel *pseudo_subchannel;
121 };
122 #define to_css(dev) container_of(dev, struct channel_subsystem, device)
123 
124 extern struct channel_subsystem *channel_subsystems[];
125 
126 /* Dummy helper which needs to change once we support more than one css. */
127 static inline struct channel_subsystem *css_by_id(u8 cssid)
128 {
129 	return channel_subsystems[0];
130 }
131 
132 /* Dummy iterator which needs to change once we support more than one css. */
133 #define for_each_css(css)						\
134 	for ((css) = channel_subsystems[0]; (css); (css) = NULL)
135 
136 /* Helper functions to build lists for the slow path. */
137 void css_schedule_eval(struct subchannel_id schid);
138 void css_schedule_eval_all(void);
139 void css_schedule_eval_all_unreg(unsigned long delay);
140 int css_complete_work(void);
141 
142 int sch_is_pseudo_sch(struct subchannel *);
143 struct schib;
144 int css_sch_is_valid(struct schib *);
145 
146 extern struct workqueue_struct *cio_work_q;
147 void css_wait_for_slow_path(void);
148 void css_sched_sch_todo(struct subchannel *sch, enum sch_todo todo);
149 #endif
150