xref: /kernel/linux/linux-5.10/drivers/s390/cio/css.h (revision 8c2ecf20)
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
37struct 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
44struct extended_cssid {
45	u8 version;
46	u8 cssid;
47} __attribute__ ((packed));
48
49struct 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
63struct subchannel;
64struct 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 */
82struct 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
101extern int css_driver_register(struct css_driver *);
102extern void css_driver_unregister(struct css_driver *);
103
104extern void css_sch_device_unregister(struct subchannel *);
105extern int css_register_subchannel(struct subchannel *);
106extern struct subchannel *css_alloc_subchannel(struct subchannel_id,
107					       struct schib *schib);
108extern struct subchannel *get_subchannel_by_schid(struct subchannel_id);
109extern int css_init_done;
110extern int max_ssid;
111int for_each_subchannel_staged(int (*fn_known)(struct subchannel *, void *),
112			       int (*fn_unknown)(struct subchannel_id,
113			       void *), void *data);
114extern int for_each_subchannel(int(*fn)(struct subchannel_id, void *), void *);
115void css_update_ssd_info(struct subchannel *sch);
116
117struct channel_subsystem {
118	u8 cssid;
119	u8 iid;
120	bool id_valid; /* cssid,iid */
121	struct channel_path *chps[__MAX_CHPID + 1];
122	struct device device;
123	struct pgid global_pgid;
124	struct mutex mutex;
125	/* channel measurement related */
126	int cm_enabled;
127	void *cub_addr1;
128	void *cub_addr2;
129	/* for orphaned ccw devices */
130	struct subchannel *pseudo_subchannel;
131};
132#define to_css(dev) container_of(dev, struct channel_subsystem, device)
133
134extern struct channel_subsystem *channel_subsystems[];
135
136/* Dummy helper which needs to change once we support more than one css. */
137static inline struct channel_subsystem *css_by_id(u8 cssid)
138{
139	return channel_subsystems[0];
140}
141
142/* Dummy iterator which needs to change once we support more than one css. */
143#define for_each_css(css)						\
144	for ((css) = channel_subsystems[0]; (css); (css) = NULL)
145
146/* Helper functions to build lists for the slow path. */
147void css_schedule_eval(struct subchannel_id schid);
148void css_schedule_eval_all(void);
149void css_schedule_eval_all_unreg(unsigned long delay);
150int css_complete_work(void);
151
152int sch_is_pseudo_sch(struct subchannel *);
153struct schib;
154int css_sch_is_valid(struct schib *);
155
156extern struct workqueue_struct *cio_work_q;
157void css_wait_for_slow_path(void);
158void css_sched_sch_todo(struct subchannel *sch, enum sch_todo todo);
159#endif
160