1 /* SPDX-License-Identifier: GPL-2.0+ */
4 * Copyright (C) 2005 IBM Corporation
7 * Ryan S. Arnold <rsa@us.ibm.com>
9 * hvc_console header information:
10 * moved here from arch/powerpc/include/asm/hvconsole.h
11 * and drivers/char/hvc_console.c
16 #include <linux/kref.h>
17 #include <linux/tty.h>
18 #include <linux/spinlock.h>
21 * This is the max number of console adapters that can/will be found as
22 * console devices on first stage console init. Any number beyond this range
23 * can't be used as a console device but is still a valid tty device.
25 #define MAX_NR_HVC_CONSOLES 16
28 * The Linux TTY code does not support dynamic addition of tty derived devices
29 * so we need to know how many tty devices we might need when space is allocated
30 * for the tty device. Since this driver supports hotplug of vty adapters we
31 * need to make sure we have enough allocated.
33 #define HVC_ALLOC_TTY_ADAPTERS 8
36 * These sizes are most efficient for vio, because they are the
37 * native transfer size. We could make them selectable in the
38 * future to better deal with backends that want other buffer sizes.
43 #define __ALIGNED__ __attribute__((__aligned__(L1_CACHE_BYTES)))
53 const struct hv_ops *ops;
57 struct work_struct tty_resize;
58 struct list_head next;
62 * the buf and its lock are used in hvc console api for putting chars,
63 * and also used in hvc_poll_put_char() for putting single char.
65 spinlock_t cons_outbuf_lock;
66 char cons_outbuf[N_OUTBUF] __ALIGNED__;
68 /* the buf is used for putting chars to tty */
69 char outbuf[] __ALIGNED__;
72 /* implemented by a low level driver */
74 int (*get_chars)(uint32_t vtermno, char *buf, int count);
75 int (*put_chars)(uint32_t vtermno, const char *buf, int count);
76 int (*flush)(uint32_t vtermno, bool wait);
78 /* Callbacks for notification. Called in open, close and hangup */
79 int (*notifier_add)(struct hvc_struct *hp, int irq);
80 void (*notifier_del)(struct hvc_struct *hp, int irq);
81 void (*notifier_hangup)(struct hvc_struct *hp, int irq);
83 /* tiocmget/set implementation */
84 int (*tiocmget)(struct hvc_struct *hp);
85 int (*tiocmset)(struct hvc_struct *hp, unsigned int set, unsigned int clear);
87 /* Callbacks to handle tty ports */
88 void (*dtr_rts)(struct hvc_struct *hp, int raise);
91 /* Register a vterm and a slot index for use as a console (console_init) */
92 extern int hvc_instantiate(uint32_t vtermno, int index,
93 const struct hv_ops *ops);
95 /* register a vterm for hvc tty operation (module_init or hotplug add) */
96 extern struct hvc_struct * hvc_alloc(uint32_t vtermno, int data,
97 const struct hv_ops *ops, int outbuf_size);
98 /* remove a vterm from hvc tty operation (module_exit or hotplug remove) */
99 extern int hvc_remove(struct hvc_struct *hp);
102 int hvc_poll(struct hvc_struct *hp);
105 /* Resize hvc tty terminal window */
106 extern void __hvc_resize(struct hvc_struct *hp, struct winsize ws);
108 static inline void hvc_resize(struct hvc_struct *hp, struct winsize ws)
112 spin_lock_irqsave(&hp->lock, flags);
113 __hvc_resize(hp, ws);
114 spin_unlock_irqrestore(&hp->lock, flags);
117 /* default notifier for irq based notification */
118 extern int notifier_add_irq(struct hvc_struct *hp, int data);
119 extern void notifier_del_irq(struct hvc_struct *hp, int data);
120 extern void notifier_hangup_irq(struct hvc_struct *hp, int data);
123 #if defined(CONFIG_XMON) && defined(CONFIG_SMP)
124 #include <asm/xmon.h>
126 static inline int cpus_are_in_xmon(void)
132 #endif // HVC_CONSOLE_H