From 26579216f3cdf1ae05f0af8412b444870a167510 Mon Sep 17 00:00:00 2001 From: Mike Frysinger Date: Mon, 15 Jun 2009 06:10:03 -0400 Subject: Blackfin: redo handling of bad irqs With the common IRQ code initializing much more of the irq_desc state, we can't blindly initialize it ourselves to the local bad_irq state. If we do, we end up wrongly clobbering many fields. So punt most of the bad irq code as the common layers will handle the default state, and simply call handle_bad_irq() directly when the IRQ we are processing is invalid. Signed-off-by: Mike Frysinger --- arch/blackfin/kernel/irqchip.c | 53 +++++++++--------------------------------- 1 file changed, 11 insertions(+), 42 deletions(-) (limited to 'arch/blackfin/kernel/irqchip.c') diff --git a/arch/blackfin/kernel/irqchip.c b/arch/blackfin/kernel/irqchip.c index 6e31e935bb3..36bba302773 100644 --- a/arch/blackfin/kernel/irqchip.c +++ b/arch/blackfin/kernel/irqchip.c @@ -38,38 +38,15 @@ #include static atomic_t irq_err_count; -static spinlock_t irq_controller_lock; - -/* - * Dummy mask/unmask handler - */ -void dummy_mask_unmask_irq(unsigned int irq) -{ -} - void ack_bad_irq(unsigned int irq) { atomic_inc(&irq_err_count); printk(KERN_ERR "IRQ: spurious interrupt %d\n", irq); } -static struct irq_chip bad_chip = { - .ack = dummy_mask_unmask_irq, - .mask = dummy_mask_unmask_irq, - .unmask = dummy_mask_unmask_irq, -}; - -static int bad_stats; static struct irq_desc bad_irq_desc = { - .status = IRQ_DISABLED, - .chip = &bad_chip, .handle_irq = handle_bad_irq, - .depth = 1, .lock = __SPIN_LOCK_UNLOCKED(irq_desc->lock), - .kstat_irqs = &bad_stats, -#ifdef CONFIG_SMP - .affinity = CPU_MASK_ALL -#endif }; #ifdef CONFIG_CPUMASK_OFFSTACK @@ -119,21 +96,13 @@ __attribute__((l1_text)) #endif asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs) { - struct pt_regs *old_regs; - struct irq_desc *desc = irq_desc + irq; #ifndef CONFIG_IPIPE unsigned short pending, other_ints; #endif - old_regs = set_irq_regs(regs); - - /* - * Some hardware gives randomly wrong interrupts. Rather - * than crashing, do something sensible. - */ - if (irq >= NR_IRQS) - desc = &bad_irq_desc; + struct pt_regs *old_regs = set_irq_regs(regs); irq_enter(); + #ifdef CONFIG_DEBUG_STACKOVERFLOW /* Debugging check for stack overflow: is there less than STACK_WARN free? */ { @@ -149,7 +118,15 @@ asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs) } } #endif - generic_handle_irq(irq); + + /* + * Some hardware gives randomly wrong interrupts. Rather + * than crashing, do something sensible. + */ + if (irq >= NR_IRQS) + handle_bad_irq(irq, &bad_irq_desc); + else + generic_handle_irq(irq); #ifndef CONFIG_IPIPE /* @@ -173,14 +150,6 @@ asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs) void __init init_IRQ(void) { - struct irq_desc *desc; - int irq; - - spin_lock_init(&irq_controller_lock); - for (irq = 0, desc = irq_desc; irq < NR_IRQS; irq++, desc++) { - *desc = bad_irq_desc; - } - init_arch_irq(); #ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND -- cgit v1.2.3-70-g09d2 From 46f288a0f983401ebadb918751d342cbf819cde5 Mon Sep 17 00:00:00 2001 From: Mike Frysinger Date: Mon, 15 Jun 2009 06:13:58 -0400 Subject: Blackfin: only build show_interrupts() when procfs is enabled Signed-off-by: Mike Frysinger --- arch/blackfin/kernel/irqchip.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/blackfin/kernel/irqchip.c') diff --git a/arch/blackfin/kernel/irqchip.c b/arch/blackfin/kernel/irqchip.c index 36bba302773..8abb642283b 100644 --- a/arch/blackfin/kernel/irqchip.c +++ b/arch/blackfin/kernel/irqchip.c @@ -54,6 +54,7 @@ static struct irq_desc bad_irq_desc = { #error "Blackfin architecture does not support CONFIG_CPUMASK_OFFSTACK." #endif +#ifdef CONFIG_PROC_FS int show_interrupts(struct seq_file *p, void *v) { int i = *(loff_t *) v, j; @@ -85,6 +86,7 @@ int show_interrupts(struct seq_file *p, void *v) } return 0; } +#endif /* * do_IRQ handles all hardware IRQs. Decoded IRQs should not -- cgit v1.2.3-70-g09d2 From 6f10fdabdce356aac3c948e659f39b6f1e2f7382 Mon Sep 17 00:00:00 2001 From: Mike Frysinger Date: Mon, 15 Jun 2009 06:18:38 -0400 Subject: Blackfin: simplify irq stack overflow checking Take a page from x86 and abstract the stack checking out of the asm_do_IRQ() function so that the result is easier to digest. Signed-off-by: Mike Frysinger --- arch/blackfin/kernel/irqchip.c | 32 +++++++++++++++++--------------- 1 file changed, 17 insertions(+), 15 deletions(-) (limited to 'arch/blackfin/kernel/irqchip.c') diff --git a/arch/blackfin/kernel/irqchip.c b/arch/blackfin/kernel/irqchip.c index 8abb642283b..7378440792a 100644 --- a/arch/blackfin/kernel/irqchip.c +++ b/arch/blackfin/kernel/irqchip.c @@ -88,6 +88,22 @@ int show_interrupts(struct seq_file *p, void *v) } #endif +#ifdef CONFIG_DEBUG_STACKOVERFLOW +static void check_stack_overflow(int irq) +{ + /* Debugging check for stack overflow: is there less than STACK_WARN free? */ + long sp = __get_SP() & (THREAD_SIZE - 1); + + if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) { + dump_stack(); + pr_emerg("irq%i: possible stack overflow only %ld bytes free\n", + irq, sp - sizeof(struct thread_info)); + } +} +#else +static inline void check_stack_overflow(int irq) { } +#endif + /* * do_IRQ handles all hardware IRQs. Decoded IRQs should not * come via this function. Instead, they should provide their @@ -105,21 +121,7 @@ asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs) irq_enter(); -#ifdef CONFIG_DEBUG_STACKOVERFLOW - /* Debugging check for stack overflow: is there less than STACK_WARN free? */ - { - long sp; - - sp = __get_SP() & (THREAD_SIZE-1); - - if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) { - dump_stack(); - printk(KERN_EMERG "%s: possible stack overflow while handling irq %i " - " only %ld bytes free\n", - __func__, irq, sp - sizeof(struct thread_info)); - } - } -#endif + check_stack_overflow(irq); /* * Some hardware gives randomly wrong interrupts. Rather -- cgit v1.2.3-70-g09d2 From 81b79c213d0200fdd16951a9fb18748fd511d810 Mon Sep 17 00:00:00 2001 From: Mike Frysinger Date: Mon, 15 Jun 2009 06:22:08 -0400 Subject: Blackfin: abstract irq14 lowering in do_irq Split out the optional IRQ14 lowering code to further simplify the asm_do_IRQ() function and keep the ifdef nest under control. Signed-off-by: Mike Frysinger --- arch/blackfin/kernel/irqchip.c | 43 ++++++++++++++++++++++++------------------ 1 file changed, 25 insertions(+), 18 deletions(-) (limited to 'arch/blackfin/kernel/irqchip.c') diff --git a/arch/blackfin/kernel/irqchip.c b/arch/blackfin/kernel/irqchip.c index 7378440792a..4b5fd36187d 100644 --- a/arch/blackfin/kernel/irqchip.c +++ b/arch/blackfin/kernel/irqchip.c @@ -104,6 +104,29 @@ static void check_stack_overflow(int irq) static inline void check_stack_overflow(int irq) { } #endif +#ifndef CONFIG_IPIPE +static void maybe_lower_to_irq14(void) +{ + unsigned short pending, other_ints; + + /* + * If we're the only interrupt running (ignoring IRQ15 which + * is for syscalls), lower our priority to IRQ14 so that + * softirqs run at that level. If there's another, + * lower-level interrupt, irq_exit will defer softirqs to + * that. If the interrupt pipeline is enabled, we are already + * running at IRQ14 priority, so we don't need this code. + */ + CSYNC(); + pending = bfin_read_IPEND() & ~0x8000; + other_ints = pending & (pending - 1); + if (other_ints == 0) + lower_to_irq14(); +} +#else +static inline void maybe_lower_to_irq14(void) { } +#endif + /* * do_IRQ handles all hardware IRQs. Decoded IRQs should not * come via this function. Instead, they should provide their @@ -114,9 +137,6 @@ __attribute__((l1_text)) #endif asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs) { -#ifndef CONFIG_IPIPE - unsigned short pending, other_ints; -#endif struct pt_regs *old_regs = set_irq_regs(regs); irq_enter(); @@ -132,21 +152,8 @@ asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs) else generic_handle_irq(irq); -#ifndef CONFIG_IPIPE - /* - * If we're the only interrupt running (ignoring IRQ15 which - * is for syscalls), lower our priority to IRQ14 so that - * softirqs run at that level. If there's another, - * lower-level interrupt, irq_exit will defer softirqs to - * that. If the interrupt pipeline is enabled, we are already - * running at IRQ14 priority, so we don't need this code. - */ - CSYNC(); - pending = bfin_read_IPEND() & ~0x8000; - other_ints = pending & (pending - 1); - if (other_ints == 0) - lower_to_irq14(); -#endif /* !CONFIG_IPIPE */ + maybe_lower_to_irq14(); + irq_exit(); set_irq_regs(old_regs); -- cgit v1.2.3-70-g09d2