diff options
author | Ingo Molnar <mingo@elte.hu> | 2008-10-09 00:17:25 +0200 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2008-10-09 00:17:25 +0200 |
commit | cdbb92b31d3c465aa96bd09f2d42c39b87b32bee (patch) | |
tree | 370e29681529882d7e4c766a19f0612885583464 /arch/mn10300/kernel/irq.c | |
parent | 2ec2b482b10a1ed3493c224f1893cddd3d33833b (diff) | |
parent | 69849375d6b13e94d08cdc94b49b11fbab454a0e (diff) |
Merge branch 'linus' into core/rcu
Diffstat (limited to 'arch/mn10300/kernel/irq.c')
-rw-r--r-- | arch/mn10300/kernel/irq.c | 71 |
1 files changed, 45 insertions, 26 deletions
diff --git a/arch/mn10300/kernel/irq.c b/arch/mn10300/kernel/irq.c index 761c434a2488..56c64ccc9c21 100644 --- a/arch/mn10300/kernel/irq.c +++ b/arch/mn10300/kernel/irq.c @@ -20,22 +20,8 @@ EXPORT_SYMBOL(__mn10300_irq_enabled_epsw); atomic_t irq_err_count; /* - * MN10300 INTC controller operations + * MN10300 interrupt controller operations */ -static void mn10300_cpupic_disable(unsigned int irq) -{ - u16 tmp = GxICR(irq); - GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_DETECT; - tmp = GxICR(irq); -} - -static void mn10300_cpupic_enable(unsigned int irq) -{ - u16 tmp = GxICR(irq); - GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_ENABLE; - tmp = GxICR(irq); -} - static void mn10300_cpupic_ack(unsigned int irq) { u16 tmp; @@ -60,26 +46,54 @@ static void mn10300_cpupic_mask_ack(unsigned int irq) static void mn10300_cpupic_unmask(unsigned int irq) { u16 tmp = GxICR(irq); - GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_ENABLE | GxICR_DETECT; + GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_ENABLE; tmp = GxICR(irq); } -static void mn10300_cpupic_end(unsigned int irq) +static void mn10300_cpupic_unmask_clear(unsigned int irq) { + /* the MN10300 PIC latches its interrupt request bit, even after the + * device has ceased to assert its interrupt line and the interrupt + * channel has been disabled in the PIC, so for level-triggered + * interrupts we need to clear the request bit when we re-enable */ u16 tmp = GxICR(irq); - GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_ENABLE; + GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_ENABLE | GxICR_DETECT; tmp = GxICR(irq); } -static struct irq_chip mn10300_cpu_pic = { - .name = "cpu", - .disable = mn10300_cpupic_disable, - .enable = mn10300_cpupic_enable, +/* + * MN10300 PIC level-triggered IRQ handling. + * + * The PIC has no 'ACK' function per se. It is possible to clear individual + * channel latches, but each latch relatches whether or not the channel is + * masked, so we need to clear the latch when we unmask the channel. + * + * Also for this reason, we don't supply an ack() op (it's unused anyway if + * mask_ack() is provided), and mask_ack() just masks. + */ +static struct irq_chip mn10300_cpu_pic_level = { + .name = "cpu_l", + .disable = mn10300_cpupic_mask, + .enable = mn10300_cpupic_unmask_clear, + .ack = NULL, + .mask = mn10300_cpupic_mask, + .mask_ack = mn10300_cpupic_mask, + .unmask = mn10300_cpupic_unmask_clear, +}; + +/* + * MN10300 PIC edge-triggered IRQ handling. + * + * We use the latch clearing function of the PIC as the 'ACK' function. + */ +static struct irq_chip mn10300_cpu_pic_edge = { + .name = "cpu_e", + .disable = mn10300_cpupic_mask, + .enable = mn10300_cpupic_unmask, .ack = mn10300_cpupic_ack, .mask = mn10300_cpupic_mask, .mask_ack = mn10300_cpupic_mask_ack, .unmask = mn10300_cpupic_unmask, - .end = mn10300_cpupic_end, }; /* @@ -114,7 +128,8 @@ void set_intr_level(int irq, u16 level) */ void set_intr_postackable(int irq) { - set_irq_handler(irq, handle_level_irq); + set_irq_chip_and_handler(irq, &mn10300_cpu_pic_level, + handle_level_irq); } /* @@ -126,8 +141,12 @@ void __init init_IRQ(void) for (irq = 0; irq < NR_IRQS; irq++) if (irq_desc[irq].chip == &no_irq_type) - set_irq_chip_and_handler(irq, &mn10300_cpu_pic, - handle_edge_irq); + /* due to the PIC latching interrupt requests, even + * when the IRQ is disabled, IRQ_PENDING is superfluous + * and we can use handle_level_irq() for edge-triggered + * interrupts */ + set_irq_chip_and_handler(irq, &mn10300_cpu_pic_edge, + handle_level_irq); unit_init_IRQ(); } |