diff options
Diffstat (limited to 'arch/alpha/kernel/irq_srm.c')
-rw-r--r-- | arch/alpha/kernel/irq_srm.c | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/arch/alpha/kernel/irq_srm.c b/arch/alpha/kernel/irq_srm.c new file mode 100644 index 00000000000..0a87e466918 --- /dev/null +++ b/arch/alpha/kernel/irq_srm.c @@ -0,0 +1,79 @@ +/* + * Handle interrupts from the SRM, assuming no additional weirdness. + */ + +#include <linux/init.h> +#include <linux/sched.h> +#include <linux/irq.h> + +#include "proto.h" +#include "irq_impl.h" + + +/* + * Is the palcode SMP safe? In other words: can we call cserve_ena/dis + * at the same time in multiple CPUs? To be safe I added a spinlock + * but it can be removed trivially if the palcode is robust against smp. + */ +DEFINE_SPINLOCK(srm_irq_lock); + +static inline void +srm_enable_irq(unsigned int irq) +{ + spin_lock(&srm_irq_lock); + cserve_ena(irq - 16); + spin_unlock(&srm_irq_lock); +} + +static void +srm_disable_irq(unsigned int irq) +{ + spin_lock(&srm_irq_lock); + cserve_dis(irq - 16); + spin_unlock(&srm_irq_lock); +} + +static unsigned int +srm_startup_irq(unsigned int irq) +{ + srm_enable_irq(irq); + return 0; +} + +static void +srm_end_irq(unsigned int irq) +{ + if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS))) + srm_enable_irq(irq); +} + +/* Handle interrupts from the SRM, assuming no additional weirdness. */ +static struct hw_interrupt_type srm_irq_type = { + .typename = "SRM", + .startup = srm_startup_irq, + .shutdown = srm_disable_irq, + .enable = srm_enable_irq, + .disable = srm_disable_irq, + .ack = srm_disable_irq, + .end = srm_end_irq, +}; + +void __init +init_srm_irqs(long max, unsigned long ignore_mask) +{ + long i; + + for (i = 16; i < max; ++i) { + if (i < 64 && ((ignore_mask >> i) & 1)) + continue; + irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL; + irq_desc[i].handler = &srm_irq_type; + } +} + +void +srm_device_interrupt(unsigned long vector, struct pt_regs * regs) +{ + int irq = (vector - 0x800) >> 4; + handle_irq(irq, regs); +} |