redonkable/remarkable-linux
redonkable/remarkable-linux
1
0
Fork 0
Code Releases Activity
remarkable-linux/include/linux/irq.h
Thomas Gleixner 1adb0850a1 genirq: reenable a nobody cared disabled irq when a new driver arrives 
Uwe Kleine-Koenig has some strange hardware where one of the shared
interrupts can be asserted during boot before the appropriate driver
loads. Requesting the shared irq line from another driver result in a
spurious interrupt storm which finally disables the interrupt line.

I have seen similar behaviour on resume before (the hardware does not
work anymore so I can not verify).

Change the spurious disable logic to increment the disable depth and
mark the interrupt with an extra flag which allows us to reenable the
interrupt when a new driver arrives which requests the same irq
line. In the worst case this will disable the irq again via the
spurious trap, but there is a decent chance that the new driver is the
one which can handle the already asserted interrupt and makes the box
usable again.

Eric Biederman said further: This case also happens on a regular basis
in kdump kernels where we deliberately don't shutdown the hardware
before starting the new kernel.  This patch should reduce the need for
using irqpoll in that situation by a small amount.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-and-Acked-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
2008-05-02 13:40:34 +02:00

395 lines
12 KiB
C
Raw Blame History

#ifndef _LINUX_IRQ_H
#define _LINUX_IRQ_H
/*
* Please do not include this file in generic code. There is currently
* no requirement for any architecture to implement anything held
* within this file.
*
* Thanks. --rmk
*/
#include <linux/smp.h>
#ifndef CONFIG_S390
#include <linux/linkage.h>
#include <linux/cache.h>
#include <linux/spinlock.h>
#include <linux/cpumask.h>
#include <linux/irqreturn.h>
#include <linux/errno.h>
#include <asm/irq.h>
#include <asm/ptrace.h>
#include <asm/irq_regs.h>
struct irq_desc;
typedef void (*irq_flow_handler_t)(unsigned int irq,
struct irq_desc *desc);
/*
* IRQ line status.
*
* Bits 0-7 are reserved for the IRQF_* bits in linux/interrupt.h
*
* IRQ types
*/
#define IRQ_TYPE_NONE 0x00000000 /* Default, unspecified type */
#define IRQ_TYPE_EDGE_RISING 0x00000001 /* Edge rising type */
#define IRQ_TYPE_EDGE_FALLING 0x00000002 /* Edge falling type */
#define IRQ_TYPE_EDGE_BOTH (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING)
#define IRQ_TYPE_LEVEL_HIGH 0x00000004 /* Level high type */
#define IRQ_TYPE_LEVEL_LOW 0x00000008 /* Level low type */
#define IRQ_TYPE_SENSE_MASK 0x0000000f /* Mask of the above */
#define IRQ_TYPE_PROBE 0x00000010 /* Probing in progress */
/* Internal flags */
#define IRQ_INPROGRESS 0x00000100 /* IRQ handler active - do not enter! */
#define IRQ_DISABLED 0x00000200 /* IRQ disabled - do not enter! */
#define IRQ_PENDING 0x00000400 /* IRQ pending - replay on enable */
#define IRQ_REPLAY 0x00000800 /* IRQ has been replayed but not acked yet */
#define IRQ_AUTODETECT 0x00001000 /* IRQ is being autodetected */
#define IRQ_WAITING 0x00002000 /* IRQ not yet seen - for autodetection */
#define IRQ_LEVEL 0x00004000 /* IRQ level triggered */
#define IRQ_MASKED 0x00008000 /* IRQ masked - shouldn't be seen again */
#define IRQ_PER_CPU 0x00010000 /* IRQ is per CPU */
#define IRQ_NOPROBE 0x00020000 /* IRQ is not valid for probing */
#define IRQ_NOREQUEST 0x00040000 /* IRQ cannot be requested */
#define IRQ_NOAUTOEN 0x00080000 /* IRQ will not be enabled on request irq */
#define IRQ_WAKEUP 0x00100000 /* IRQ triggers system wakeup */
#define IRQ_MOVE_PENDING 0x00200000 /* need to re-target IRQ destination */
#define IRQ_NO_BALANCING 0x00400000 /* IRQ is excluded from balancing */
#define IRQ_SPURIOUS_DISABLED 0x00800000 /* IRQ was disabled by the spurious trap */
#ifdef CONFIG_IRQ_PER_CPU
# define CHECK_IRQ_PER_CPU(var) ((var) & IRQ_PER_CPU)
# define IRQ_NO_BALANCING_MASK (IRQ_PER_CPU | IRQ_NO_BALANCING)
#else
# define CHECK_IRQ_PER_CPU(var) 0
# define IRQ_NO_BALANCING_MASK IRQ_NO_BALANCING
#endif
struct proc_dir_entry;
struct msi_desc;
/**
* struct irq_chip - hardware interrupt chip descriptor
*
* @name: name for /proc/interrupts
* @startup: start up the interrupt (defaults to ->enable if NULL)
* @shutdown: shut down the interrupt (defaults to ->disable if NULL)
* @enable: enable the interrupt (defaults to chip->unmask if NULL)
* @disable: disable the interrupt (defaults to chip->mask if NULL)
* @ack: start of a new interrupt
* @mask: mask an interrupt source
* @mask_ack: ack and mask an interrupt source
* @unmask: unmask an interrupt source
* @eoi: end of interrupt - chip level
* @end: end of interrupt - flow level
* @set_affinity: set the CPU affinity on SMP machines
* @retrigger: resend an IRQ to the CPU
* @set_type: set the flow type (IRQ_TYPE_LEVEL/etc.) of an IRQ
* @set_wake: enable/disable power-management wake-on of an IRQ
*
* @release: release function solely used by UML
* @typename: obsoleted by name, kept as migration helper
*/
struct irq_chip {
const char *name;
unsigned int (*startup)(unsigned int irq);
void (*shutdown)(unsigned int irq);
void (*enable)(unsigned int irq);
void (*disable)(unsigned int irq);
void (*ack)(unsigned int irq);
void (*mask)(unsigned int irq);
void (*mask_ack)(unsigned int irq);
void (*unmask)(unsigned int irq);
void (*eoi)(unsigned int irq);
void (*end)(unsigned int irq);
void (*set_affinity)(unsigned int irq, cpumask_t dest);
int (*retrigger)(unsigned int irq);
int (*set_type)(unsigned int irq, unsigned int flow_type);
int (*set_wake)(unsigned int irq, unsigned int on);
/* Currently used only by UML, might disappear one day.*/
#ifdef CONFIG_IRQ_RELEASE_METHOD
void (*release)(unsigned int irq, void *dev_id);
#endif
/*
* For compatibility, ->typename is copied into ->name.
* Will disappear.
*/
const char *typename;
};
/**
* struct irq_desc - interrupt descriptor
*
* @handle_irq: highlevel irq-events handler [if NULL, __do_IRQ()]
* @chip: low level interrupt hardware access
* @msi_desc: MSI descriptor
* @handler_data: per-IRQ data for the irq_chip methods
* @chip_data: platform-specific per-chip private data for the chip
* methods, to allow shared chip implementations
* @action: the irq action chain
* @status: status information
* @depth: disable-depth, for nested irq_disable() calls
* @wake_depth: enable depth, for multiple set_irq_wake() callers
* @irq_count: stats field to detect stalled irqs
* @irqs_unhandled: stats field for spurious unhandled interrupts
* @last_unhandled: aging timer for unhandled count
* @lock: locking for SMP
* @affinity: IRQ affinity on SMP
* @cpu: cpu index useful for balancing
* @pending_mask: pending rebalanced interrupts
* @dir: /proc/irq/ procfs entry
* @affinity_entry: /proc/irq/smp_affinity procfs entry on SMP
* @name: flow handler name for /proc/interrupts output
*/
struct irq_desc {
irq_flow_handler_t handle_irq;
struct irq_chip *chip;
struct msi_desc *msi_desc;
void *handler_data;
void *chip_data;
struct irqaction *action; /* IRQ action list */
unsigned int status; /* IRQ status */
unsigned int depth; /* nested irq disables */
unsigned int wake_depth; /* nested wake enables */
unsigned int irq_count; /* For detecting broken IRQs */
unsigned int irqs_unhandled;
unsigned long last_unhandled; /* Aging timer for unhandled count */
spinlock_t lock;
#ifdef CONFIG_SMP
cpumask_t affinity;
unsigned int cpu;
#endif
#if defined(CONFIG_GENERIC_PENDING_IRQ) || defined(CONFIG_IRQBALANCE)
cpumask_t pending_mask;
#endif
#ifdef CONFIG_PROC_FS
struct proc_dir_entry *dir;
#endif
const char *name;
} ____cacheline_internodealigned_in_smp;
extern struct irq_desc irq_desc[NR_IRQS];
/*
* Migration helpers for obsolete names, they will go away:
*/
#define hw_interrupt_type irq_chip
typedef struct irq_chip hw_irq_controller;
#define no_irq_type no_irq_chip
typedef struct irq_desc irq_desc_t;
/*
* Pick up the arch-dependent methods:
*/
#include <asm/hw_irq.h>
extern int setup_irq(unsigned int irq, struct irqaction *new);
#ifdef CONFIG_GENERIC_HARDIRQS
#ifndef handle_dynamic_tick
# define handle_dynamic_tick(a) do { } while (0)
#endif
#ifdef CONFIG_SMP
#if defined(CONFIG_GENERIC_PENDING_IRQ) || defined(CONFIG_IRQBALANCE)
void set_pending_irq(unsigned int irq, cpumask_t mask);
void move_native_irq(int irq);
void move_masked_irq(int irq);
#else /* CONFIG_GENERIC_PENDING_IRQ || CONFIG_IRQBALANCE */
static inline void move_irq(int irq)
{
}
static inline void move_native_irq(int irq)
{
}
static inline void move_masked_irq(int irq)
{
}
static inline void set_pending_irq(unsigned int irq, cpumask_t mask)
{
}
#endif /* CONFIG_GENERIC_PENDING_IRQ */
#else /* CONFIG_SMP */
#define move_native_irq(x)
#define move_masked_irq(x)
#endif /* CONFIG_SMP */
#ifdef CONFIG_IRQBALANCE
extern void set_balance_irq_affinity(unsigned int irq, cpumask_t mask);
#else
static inline void set_balance_irq_affinity(unsigned int irq, cpumask_t mask)
{
}
#endif
#ifdef CONFIG_AUTO_IRQ_AFFINITY
extern int select_smp_affinity(unsigned int irq);
#else
static inline int select_smp_affinity(unsigned int irq)
{
return 1;
}
#endif
extern int no_irq_affinity;
static inline int irq_balancing_disabled(unsigned int irq)
{
return irq_desc[irq].status & IRQ_NO_BALANCING_MASK;
}
/* Handle irq action chains: */
extern int handle_IRQ_event(unsigned int irq, struct irqaction *action);
/*
* Built-in IRQ handlers for various IRQ types,
* callable via desc->chip->handle_irq()
*/
extern void handle_level_irq(unsigned int irq, struct irq_desc *desc);
extern void handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc);
extern void handle_edge_irq(unsigned int irq, struct irq_desc *desc);
extern void handle_simple_irq(unsigned int irq, struct irq_desc *desc);
extern void handle_percpu_irq(unsigned int irq, struct irq_desc *desc);
extern void handle_bad_irq(unsigned int irq, struct irq_desc *desc);
/*
* Monolithic do_IRQ implementation.
*/
#ifndef CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ
extern unsigned int __do_IRQ(unsigned int irq);
#endif
/*
* Architectures call this to let the generic IRQ layer
* handle an interrupt. If the descriptor is attached to an
* irqchip-style controller then we call the ->handle_irq() handler,
* and it calls __do_IRQ() if it's attached to an irqtype-style controller.
*/
static inline void generic_handle_irq(unsigned int irq)
{
struct irq_desc *desc = irq_desc + irq;
#ifdef CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ
desc->handle_irq(irq, desc);
#else
if (likely(desc->handle_irq))
desc->handle_irq(irq, desc);
else
__do_IRQ(irq);
#endif
}
/* Handling of unhandled and spurious interrupts: */
extern void note_interrupt(unsigned int irq, struct irq_desc *desc,
int action_ret);
/* Resending of interrupts :*/
void check_irq_resend(struct irq_desc *desc, unsigned int irq);
/* Enable/disable irq debugging output: */
extern int noirqdebug_setup(char *str);
/* Checks whether the interrupt can be requested by request_irq(): */
extern int can_request_irq(unsigned int irq, unsigned long irqflags);
/* Dummy irq-chip implementations: */
extern struct irq_chip no_irq_chip;
extern struct irq_chip dummy_irq_chip;
extern void
set_irq_chip_and_handler(unsigned int irq, struct irq_chip *chip,
irq_flow_handler_t handle);
extern void
set_irq_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
irq_flow_handler_t handle, const char *name);
extern void
__set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
const char *name);
/* caller has locked the irq_desc and both params are valid */
static inline void __set_irq_handler_unlocked(int irq,
irq_flow_handler_t handler)
{
irq_desc[irq].handle_irq = handler;
}
/*
* Set a highlevel flow handler for a given IRQ:
*/
static inline void
set_irq_handler(unsigned int irq, irq_flow_handler_t handle)
{
__set_irq_handler(irq, handle, 0, NULL);
}
/*
* Set a highlevel chained flow handler for a given IRQ.
* (a chained handler is automatically enabled and set to
* IRQ_NOREQUEST and IRQ_NOPROBE)
*/
static inline void
set_irq_chained_handler(unsigned int irq,
irq_flow_handler_t handle)
{
__set_irq_handler(irq, handle, 1, NULL);
}
extern void set_irq_noprobe(unsigned int irq);
extern void set_irq_probe(unsigned int irq);
/* Handle dynamic irq creation and destruction */
extern int create_irq(void);
extern void destroy_irq(unsigned int irq);
/* Test to see if a driver has successfully requested an irq */
static inline int irq_has_action(unsigned int irq)
{
struct irq_desc *desc = irq_desc + irq;
return desc->action != NULL;
}
/* Dynamic irq helper functions */
extern void dynamic_irq_init(unsigned int irq);
extern void dynamic_irq_cleanup(unsigned int irq);
/* Set/get chip/data for an IRQ: */
extern int set_irq_chip(unsigned int irq, struct irq_chip *chip);
extern int set_irq_data(unsigned int irq, void *data);
extern int set_irq_chip_data(unsigned int irq, void *data);
extern int set_irq_type(unsigned int irq, unsigned int type);
extern int set_irq_msi(unsigned int irq, struct msi_desc *entry);
#define get_irq_chip(irq) (irq_desc[irq].chip)
#define get_irq_chip_data(irq) (irq_desc[irq].chip_data)
#define get_irq_data(irq) (irq_desc[irq].handler_data)
#define get_irq_msi(irq) (irq_desc[irq].msi_desc)
#endif /* CONFIG_GENERIC_HARDIRQS */
#endif /* !CONFIG_S390 */
#endif /* _LINUX_IRQ_H */
View git blame Copy permalink