From ea160584574e345495e75ee4a7d3a7dbcad9e16c Mon Sep 17 00:00:00 2001 From: oftedal Date: Wed, 1 Jun 2011 11:04:20 +0000 Subject: [PATCH] Do not skip interrupt sources in sun4d interrupt handler and acknowledge interrupts correctly During the introduction of genirq on sparc32 bugs were introduced in the interrupt handler for sun4d. The interrupts handler checks the status of the various sbus interfaces in the system and generates a virtual interrupt, based upon the location of the interrupt source. This lookup was broken by restructuring the code in such a way that index and shift operations were performed prior to comparing this against the values read from the interrupt controllers. This could cause the handler to loop eternally as the interrupt source could be skipped before any check was performed. Additionally sun4d_encode_irq performs shifting internally, so it should not be performed twice. In sun4d_unmask interrupts were not correctly acknowledged, as the corresponding bit it the interrupt mask was not actually cleared. Signed-off-by: Kjetil Oftedal Signed-off-by: David S. Miller --- arch/sparc/kernel/sun4d_irq.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) diff --git a/arch/sparc/kernel/sun4d_irq.c b/arch/sparc/kernel/sun4d_irq.c index 487c1bb374f5..eaec8a90fb9f 100644 --- a/arch/sparc/kernel/sun4d_irq.c +++ b/arch/sparc/kernel/sun4d_irq.c @@ -103,10 +103,9 @@ static void sun4d_sbus_handler_irq(int sbusl) sbil = (sbusl << 2); /* Loop for each pending SBI */ - for (sbino = 0; bus_mask; sbino++) { + for (sbino = 0; bus_mask; sbino++, bus_mask >>= 1) { unsigned int idx, mask; - bus_mask >>= 1; if (!(bus_mask & 1)) continue; /* XXX This seems to ACK the irq twice. acquire_sbi() @@ -118,19 +117,16 @@ static void sun4d_sbus_handler_irq(int sbusl) mask &= (0xf << sbil); /* Loop for each pending SBI slot */ - idx = 0; slot = (1 << sbil); - while (mask != 0) { + for (idx = 0; mask != 0; idx++, slot <<= 1) { unsigned int pil; struct irq_bucket *p; - idx++; - slot <<= 1; if (!(mask & slot)) continue; mask &= ~slot; - pil = sun4d_encode_irq(sbino, sbil, idx); + pil = sun4d_encode_irq(sbino, sbusl, idx); p = irq_map[pil]; while (p) { @@ -218,10 +214,10 @@ static void sun4d_unmask_irq(struct irq_data *data) #ifdef CONFIG_SMP spin_lock_irqsave(&sun4d_imsk_lock, flags); - cc_set_imsk_other(cpuid, cc_get_imsk_other(cpuid) | ~(1 << real_irq)); + cc_set_imsk_other(cpuid, cc_get_imsk_other(cpuid) & ~(1 << real_irq)); spin_unlock_irqrestore(&sun4d_imsk_lock, flags); #else - cc_set_imsk(cc_get_imsk() | ~(1 << real_irq)); + cc_set_imsk(cc_get_imsk() & ~(1 << real_irq)); #endif }