From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: [PATCH v2 16/16] xen/arm: IRQ: Handle multiple action per IRQ Date: Thu, 3 Apr 2014 21:42:07 +0100 Message-ID: <1396557727-19102-17-git-send-email-julien.grall@linaro.org> References: <1396557727-19102-1-git-send-email-julien.grall@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta4.messagelabs.com ([85.158.143.247]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1WVoTI-0008Mp-Cg for xen-devel@lists.xenproject.org; Thu, 03 Apr 2014 20:42:48 +0000 Received: by mail-wg0-f47.google.com with SMTP id x12so2465886wgg.6 for ; Thu, 03 Apr 2014 13:42:43 -0700 (PDT) In-Reply-To: <1396557727-19102-1-git-send-email-julien.grall@linaro.org> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: xen-devel@lists.xenproject.org Cc: Keir Fraser , ian.campbell@citrix.com, Julien Grall , tim@xen.org, stefano.stabellini@citrix.com, Jan Beulich List-Id: xen-devel@lists.xenproject.org On ARM, it may happen (eg ARM SMMU) to setup multiple handler for the same interrupt. To be able to use multiple action, the driver has to explicitly call {setup,request}_irq_flags (newly created) with IRQ_SHARED as 3rd parameter. The behavior stays the same on x86, e.g only one action is handled. Signed-off-by: Julien Grall Cc: Keir Fraser Cc: Jan Beulich --- Changes in v2: - Explain design choice - Introduce CONFIG_IRQ_HAS_MULTIPLE_ACTION - Use list instead of custom pointer - release_irq should not shutdown the IRQ at the beginning - Add IRQ_SHARED flags - Introduce request_irq_flags and setup_irq_flags - Fix compilation on x86. Some code are creating the irqaction via = { ... } so the "next" field should be moved toward the end --- xen/arch/arm/irq.c | 106 +++++++++++++++++++++++++++++++----------- xen/common/irq.c | 3 ++ xen/include/asm-arm/config.h | 2 + xen/include/asm-arm/irq.h | 7 +++ xen/include/xen/irq.h | 8 ++++ 5 files changed, 99 insertions(+), 27 deletions(-) diff --git a/xen/arch/arm/irq.c b/xen/arch/arm/irq.c index ef67279..556c2e1 100644 --- a/xen/arch/arm/irq.c +++ b/xen/arch/arm/irq.c @@ -68,7 +68,6 @@ static int __init init_irq_data(void) struct irq_desc *desc = irq_to_desc(irq); init_one_irq_desc(desc); desc->irq = irq; - desc->action = NULL; } return 0; @@ -82,7 +81,6 @@ static int __cpuinit init_local_irq_data(void) struct irq_desc *desc = irq_to_desc(irq); init_one_irq_desc(desc); desc->irq = irq; - desc->action = NULL; /* PPIs are include in local_irqs, we have to copy the IRQ type from * CPU0 otherwise we may miss the type if the IRQ type has been @@ -107,16 +105,21 @@ void __cpuinit init_secondary_IRQ(void) static inline struct domain *irq_get_domain(struct irq_desc *desc) { + struct irqaction *action; + ASSERT(spin_is_locked(&desc->lock)); ASSERT(desc->status & IRQ_GUEST); - ASSERT(desc->action != NULL); + ASSERT(!list_empty(&desc->action)); + + action = list_entry(desc->action.next, struct irqaction, next); - return desc->action->dev_id; + return action->dev_id; } -int request_irq(unsigned int irq, - void (*handler)(int, void *, struct cpu_user_regs *), - const char *devname, void *dev_id) +int request_irq_flags(unsigned int irq, + void (*handler)(int, void *, struct cpu_user_regs *), + unsigned int irqflags, + const char *devname, void *dev_id) { struct irqaction *action; int retval; @@ -141,18 +144,24 @@ int request_irq(unsigned int irq, action->dev_id = dev_id; action->free_on_release = 1; - retval = setup_irq(irq, action); + retval = setup_irq_flags(irq, action, irqflags); if ( retval ) xfree(action); return retval; } +int request_irq(unsigned int irq, + void (*handler)(int, void *, struct cpu_user_regs *), + const char *devname, void *dev_id) +{ + return request_irq_flags(irq, handler, 0, devname, dev_id); +} + /* Dispatch an interrupt */ void do_IRQ(struct cpu_user_regs *regs, unsigned int irq, int is_fiq) { struct irq_desc *desc = irq_to_desc(irq); - struct irqaction *action = desc->action; /* TODO: perfc_incr(irqs); */ @@ -163,7 +172,7 @@ void do_IRQ(struct cpu_user_regs *regs, unsigned int irq, int is_fiq) spin_lock(&desc->lock); desc->handler->ack(desc); - if ( action == NULL ) + if ( list_empty(&desc->action) ) { printk("Unknown %s %#3.3x\n", is_fiq ? "FIQ" : "IRQ", irq); @@ -195,12 +204,14 @@ void do_IRQ(struct cpu_user_regs *regs, unsigned int irq, int is_fiq) desc->status |= IRQ_INPROGRESS; - action = desc->action; while ( desc->status & IRQ_PENDING ) { + struct irqaction *action, *next; + desc->status &= ~IRQ_PENDING; spin_unlock_irq(&desc->lock); - action->handler(irq, action->dev_id, regs); + list_for_each_entry_safe(action, next, &desc->action, next) + action->handler(irq, action->dev_id, regs); spin_lock_irq(&desc->lock); } @@ -217,39 +228,75 @@ void release_irq(unsigned int irq, const void *dev_id) { struct irq_desc *desc; unsigned long flags; - struct irqaction *action; + struct irqaction *action; + bool_t found = 0; desc = irq_to_desc(irq); spin_lock_irqsave(&desc->lock,flags); - desc->handler->shutdown(desc); + list_for_each_entry(action, &desc->action, next) + { + if ( action->dev_id == dev_id ) + { + found = 1; + break; + } + } - action = desc->action; - desc->action = NULL; - desc->status &= ~IRQ_GUEST; + if ( !found ) + { + printk(XENLOG_WARNING "Trying to free already-free IRQ %u\n", irq); + return; + } + + /* Found it - remove it from the action list */ + list_del_init(&action->next); + + /* If this was the last action, shut down the IRQ */ + if ( list_empty(&desc->action) ) + { + desc->handler->shutdown(desc); + desc->status &= ~IRQ_GUEST; + } spin_unlock_irqrestore(&desc->lock,flags); /* Wait to make sure it's not being used on another CPU */ do { smp_mb(); } while ( desc->status & IRQ_INPROGRESS ); - if ( action && action->free_on_release ) + if ( action->free_on_release ) xfree(action); } -static int __setup_irq(struct irq_desc *desc, struct irqaction *new) +static int __setup_irq(struct irq_desc *desc, struct irqaction *new, + unsigned int irqflags) { - if ( desc->action != NULL ) - return -EBUSY; + bool_t shared = !!(irqflags & IRQ_SHARED); + + ASSERT(new != NULL); - desc->action = new; + /* Sanity checks: + * - if the IRQ is marked as shared + * - dev_id is not NULL when IRQ_SHARED is set + */ + if ( !list_empty(&desc->action) && (!(desc->status & IRQ_SHARED) || !shared) ) + return -EINVAL; + if ( shared && new->dev_id == NULL ) + return -EINVAL; + + if ( shared ) + desc->status |= IRQ_SHARED; + + INIT_LIST_HEAD(&new->next); + list_add_tail(&new->next, &desc->action); dsb(sy); return 0; } -int setup_irq(unsigned int irq, struct irqaction *new) +int setup_irq_flags(unsigned int irq, struct irqaction *new, + unsigned int irqflags) { int rc; unsigned long flags; @@ -270,9 +317,9 @@ int setup_irq(unsigned int irq, struct irqaction *new) return -EBUSY; } - disabled = (desc->action == NULL); + disabled = list_empty(&desc->action); - rc = __setup_irq(desc, new); + rc = __setup_irq(desc, new, irqflags); if ( rc ) goto err; @@ -297,6 +344,11 @@ err: return rc; } +int setup_irq(unsigned int irq, struct irqaction *new) +{ + return setup_irq_flags(irq, new, 0); +} + int route_dt_irq_to_guest(struct domain *d, const struct dt_irq *irq, const char * devname) { @@ -320,7 +372,7 @@ int route_dt_irq_to_guest(struct domain *d, const struct dt_irq *irq, * - Otherwise -> For now, don't allow the IRQ to be shared between * Xen and domains. */ - if ( desc->action != NULL ) + if ( !list_empty(&desc->action) ) { struct domain *ad = irq_get_domain(desc); @@ -337,7 +389,7 @@ int route_dt_irq_to_guest(struct domain *d, const struct dt_irq *irq, goto out; } - retval = __setup_irq(desc, action); + retval = __setup_irq(desc, action, 0); if ( retval ) { xfree(action); diff --git a/xen/common/irq.c b/xen/common/irq.c index 3e55dfa..688e48a 100644 --- a/xen/common/irq.c +++ b/xen/common/irq.c @@ -17,6 +17,9 @@ int init_one_irq_desc(struct irq_desc *desc) spin_lock_init(&desc->lock); cpumask_setall(desc->affinity); INIT_LIST_HEAD(&desc->rl_link); +#ifdef CONFIG_IRQ_HAS_MULTIPLE_ACTION + INIT_LIST_HEAD(&desc->action); +#endif err = arch_init_one_irq_desc(desc); if ( err ) diff --git a/xen/include/asm-arm/config.h b/xen/include/asm-arm/config.h index 5b7b1a8..079e8b9 100644 --- a/xen/include/asm-arm/config.h +++ b/xen/include/asm-arm/config.h @@ -37,6 +37,8 @@ #define CONFIG_VIDEO 1 +#define CONFIG_IRQ_HAS_MULTIPLE_ACTION 1 + #define OPT_CONSOLE_STR "dtuart" #ifdef MAX_PHYS_CPUS diff --git a/xen/include/asm-arm/irq.h b/xen/include/asm-arm/irq.h index ad2cc18..80dd452 100644 --- a/xen/include/asm-arm/irq.h +++ b/xen/include/asm-arm/irq.h @@ -45,6 +45,13 @@ int route_dt_irq_to_guest(struct domain *d, const struct dt_irq *irq, unsigned int platform_get_irq(const struct dt_device_node *device, int index); +int request_irq_flags(unsigned int irq, + void (*handler)(int, void *, struct cpu_user_regs *), + unsigned int irqflags, + const char * devname, void *dev_id); +int setup_irq_flags(unsigned int irq, struct irqaction *new, + unsigned int irqflags); + #endif /* _ASM_HW_IRQ_H */ /* * Local variables: diff --git a/xen/include/xen/irq.h b/xen/include/xen/irq.h index 1f8bdb3..49a805b 100644 --- a/xen/include/xen/irq.h +++ b/xen/include/xen/irq.h @@ -14,6 +14,9 @@ struct irqaction { const char *name; void *dev_id; bool_t free_on_release; +#ifdef CONFIG_IRQ_HAS_MULTIPLE_ACTION + struct list_head next; +#endif }; /* @@ -27,6 +30,7 @@ struct irqaction { #define IRQ_MOVE_PENDING (1u<<5) /* IRQ is migrating to another CPUs */ #define IRQ_PER_CPU (1u<<6) /* IRQ is per CPU */ #define IRQ_GUEST_EOI_PENDING (1u<<7) /* IRQ was disabled, pending a guest EOI */ +#define IRQ_SHARED (1<<8) /* IRQ is shared */ /* Special IRQ numbers. */ #define AUTO_ASSIGN_IRQ (-1) @@ -68,7 +72,11 @@ typedef struct irq_desc { unsigned int status; /* IRQ status */ hw_irq_controller *handler; struct msi_desc *msi_desc; +#ifdef CONFIG_IRQ_HAS_MULTIPLE_ACTION + struct list_head action; /* IRQ action list */ +#else struct irqaction *action; /* IRQ action list */ +#endif int irq; spinlock_t lock; struct arch_irq_desc arch; -- 1.7.10.4