![Sam Mendoza-Jonas](/assets/img/avatar_default.png)
Commit 2def86a720
("hvc: Convert to using interrupts instead of opal
events") enabled the use of interrupts in the hvc_driver for OPAL
platforms. However on machines with more than one hvc console, any
console after the first will fail to register an interrupt handler in
notifier_add_irq() since all consoles share the same IRQ number but do
not set the IRQF_SHARED flag:
genirq: Flags mismatch irq 31. 00000000 (hvc_console) vs. 00000000 (hvc_console)
hvc_open: request_irq failed with rc -16.
This error propagates up to hvc_open() and the console is closed, but
OPAL will still generate interrupts that are not handled, leading to
rcu_sched stall warnings.
Set IRQF_SHARED when calling request_irq(), allowing additional consoles
to start properly. This is only set for consoles handled by
hvc_opal_probe(), leaving other types unaffected.
Signed-off-by: Samuel Mendoza-Jonas <sam@mendozajonas.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
126 lines
3.8 KiB
C
126 lines
3.8 KiB
C
/*
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* hvc_console.h
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* Copyright (C) 2005 IBM Corporation
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*
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* Author(s):
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* Ryan S. Arnold <rsa@us.ibm.com>
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*
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* hvc_console header information:
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* moved here from arch/powerpc/include/asm/hvconsole.h
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* and drivers/char/hvc_console.c
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#ifndef HVC_CONSOLE_H
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#define HVC_CONSOLE_H
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#include <linux/kref.h>
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#include <linux/tty.h>
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#include <linux/spinlock.h>
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/*
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* This is the max number of console adapters that can/will be found as
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* console devices on first stage console init. Any number beyond this range
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* can't be used as a console device but is still a valid tty device.
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*/
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#define MAX_NR_HVC_CONSOLES 16
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/*
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* The Linux TTY code does not support dynamic addition of tty derived devices
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* so we need to know how many tty devices we might need when space is allocated
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* for the tty device. Since this driver supports hotplug of vty adapters we
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* need to make sure we have enough allocated.
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*/
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#define HVC_ALLOC_TTY_ADAPTERS 8
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struct hvc_struct {
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struct tty_port port;
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spinlock_t lock;
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int index;
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int do_wakeup;
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char *outbuf;
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int outbuf_size;
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int n_outbuf;
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uint32_t vtermno;
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const struct hv_ops *ops;
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int irq_requested;
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int data;
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struct winsize ws;
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struct work_struct tty_resize;
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struct list_head next;
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unsigned long flags;
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};
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/* implemented by a low level driver */
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struct hv_ops {
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int (*get_chars)(uint32_t vtermno, char *buf, int count);
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int (*put_chars)(uint32_t vtermno, const char *buf, int count);
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/* Callbacks for notification. Called in open, close and hangup */
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int (*notifier_add)(struct hvc_struct *hp, int irq);
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void (*notifier_del)(struct hvc_struct *hp, int irq);
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void (*notifier_hangup)(struct hvc_struct *hp, int irq);
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/* tiocmget/set implementation */
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int (*tiocmget)(struct hvc_struct *hp);
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int (*tiocmset)(struct hvc_struct *hp, unsigned int set, unsigned int clear);
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/* Callbacks to handle tty ports */
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void (*dtr_rts)(struct hvc_struct *hp, int raise);
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};
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/* Register a vterm and a slot index for use as a console (console_init) */
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extern int hvc_instantiate(uint32_t vtermno, int index,
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const struct hv_ops *ops);
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/* register a vterm for hvc tty operation (module_init or hotplug add) */
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extern struct hvc_struct * hvc_alloc(uint32_t vtermno, int data,
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const struct hv_ops *ops, int outbuf_size);
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/* remove a vterm from hvc tty operation (module_exit or hotplug remove) */
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extern int hvc_remove(struct hvc_struct *hp);
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/* data available */
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int hvc_poll(struct hvc_struct *hp);
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void hvc_kick(void);
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/* Resize hvc tty terminal window */
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extern void __hvc_resize(struct hvc_struct *hp, struct winsize ws);
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static inline void hvc_resize(struct hvc_struct *hp, struct winsize ws)
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{
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unsigned long flags;
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spin_lock_irqsave(&hp->lock, flags);
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__hvc_resize(hp, ws);
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spin_unlock_irqrestore(&hp->lock, flags);
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}
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/* default notifier for irq based notification */
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extern int notifier_add_irq(struct hvc_struct *hp, int data);
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extern void notifier_del_irq(struct hvc_struct *hp, int data);
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extern void notifier_hangup_irq(struct hvc_struct *hp, int data);
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#if defined(CONFIG_XMON) && defined(CONFIG_SMP)
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#include <asm/xmon.h>
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#else
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static inline int cpus_are_in_xmon(void)
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{
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return 0;
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}
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#endif
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#endif // HVC_CONSOLE_H
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