From 9cf9e19667f6ce01bd509a154157270069f836f9 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Fri, 26 Jan 2007 19:08:05 -0800 Subject: [PATCH] [POWERPC] ps3: cleanup interrupt bmp routines Change the PS3 interrupt bitmask routines to be lockless. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Geoff Levand Acked-by: Arnd Bergmann Signed-off-by: Paul Mackerras --- arch/powerpc/platforms/ps3/interrupt.c | 85 ++++++++++++-------------- 1 file changed, 38 insertions(+), 47 deletions(-) diff --git a/arch/powerpc/platforms/ps3/interrupt.c b/arch/powerpc/platforms/ps3/interrupt.c index 7a4ca056dd..d3c97fbff7 100644 --- a/arch/powerpc/platforms/ps3/interrupt.c +++ b/arch/powerpc/platforms/ps3/interrupt.c @@ -380,34 +380,50 @@ static void dump_bmp(struct ps3_private* pd) {}; static void ps3_chip_mask(unsigned int virq) { - unsigned long flags; struct ps3_private *pd = get_irq_chip_data(virq); + unsigned long bit = 0x8000000000000000UL >> virq; + unsigned long *p = &pd->bmp.mask; + unsigned long old; + unsigned long flags; pr_debug("%s:%d: cpu %u, virq %d\n", __func__, __LINE__, pd->cpu, virq); - BUG_ON(virq < NUM_ISA_INTERRUPTS); - BUG_ON(virq > PS3_PLUG_MAX); + local_irq_save(flags); + asm volatile( + "1: ldarx %0,0,%3\n" + "andc %0,%0,%2\n" + "stdcx. %0,0,%3\n" + "bne- 1b" + : "=&r" (old), "+m" (*p) + : "r" (bit), "r" (p) + : "cc" ); - spin_lock_irqsave(&pd->bmp.lock, flags); - pd->bmp.mask &= ~(0x8000000000000000UL >> virq); lv1_did_update_interrupt_mask(pd->node, pd->cpu); - spin_unlock_irqrestore(&pd->bmp.lock, flags); + local_irq_restore(flags); } static void ps3_chip_unmask(unsigned int virq) { - unsigned long flags; struct ps3_private *pd = get_irq_chip_data(virq); + unsigned long bit = 0x8000000000000000UL >> virq; + unsigned long *p = &pd->bmp.mask; + unsigned long old; + unsigned long flags; pr_debug("%s:%d: cpu %u, virq %d\n", __func__, __LINE__, pd->cpu, virq); - BUG_ON(virq < NUM_ISA_INTERRUPTS); - BUG_ON(virq > PS3_PLUG_MAX); + local_irq_save(flags); + asm volatile( + "1: ldarx %0,0,%3\n" + "or %0,%0,%2\n" + "stdcx. %0,0,%3\n" + "bne- 1b" + : "=&r" (old), "+m" (*p) + : "r" (bit), "r" (p) + : "cc" ); - spin_lock_irqsave(&pd->bmp.lock, flags); - pd->bmp.mask |= (0x8000000000000000UL >> virq); lv1_did_update_interrupt_mask(pd->node, pd->cpu); - spin_unlock_irqrestore(&pd->bmp.lock, flags); + local_irq_restore(flags); } static void ps3_chip_eoi(unsigned int virq) @@ -481,46 +497,21 @@ void __init ps3_register_ipi_debug_brk(unsigned int cpu, unsigned int virq) cpu, virq, pd->bmp.ipi_debug_brk_mask); } -static int bmp_get_and_clear_status_bit(struct ps3_bmp *m) +unsigned int ps3_get_irq(void) { - unsigned long flags; - unsigned int bit; - unsigned long x; - - spin_lock_irqsave(&m->lock, flags); + struct ps3_private *pd = &__get_cpu_var(ps3_private); + unsigned long x = (pd->bmp.status & pd->bmp.mask); + unsigned int plug; /* check for ipi break first to stop this cpu ASAP */ - if (m->status & m->ipi_debug_brk_mask) { - m->status &= ~m->ipi_debug_brk_mask; - spin_unlock_irqrestore(&m->lock, flags); - return __ilog2(m->ipi_debug_brk_mask); - } - - x = (m->status & m->mask); - - for (bit = NUM_ISA_INTERRUPTS, x <<= bit; x; bit++, x <<= 1) - if (x & 0x8000000000000000UL) { - m->status &= ~(0x8000000000000000UL >> bit); - spin_unlock_irqrestore(&m->lock, flags); - return bit; - } - - spin_unlock_irqrestore(&m->lock, flags); - - pr_debug("%s:%d: not found\n", __func__, __LINE__); - return -1; -} - -unsigned int ps3_get_irq(void) -{ - int plug; - - struct ps3_private *pd = &__get_cpu_var(ps3_private); + if (x & pd->bmp.ipi_debug_brk_mask) + x &= pd->bmp.ipi_debug_brk_mask; - plug = bmp_get_and_clear_status_bit(&pd->bmp); + asm volatile("cntlzd %0,%1" : "=r" (plug) : "r" (x)); + plug &= 0x3f; - if (plug < 1) { + if (unlikely(plug) == NO_IRQ) { pr_debug("%s:%d: no plug found: cpu %u\n", __func__, __LINE__, pd->cpu); dump_bmp(&per_cpu(ps3_private, 0)); @@ -529,7 +520,7 @@ unsigned int ps3_get_irq(void) } #if defined(DEBUG) - if (plug < NUM_ISA_INTERRUPTS || plug > PS3_PLUG_MAX) { + if (unlikely(plug < NUM_ISA_INTERRUPTS || plug > PS3_PLUG_MAX)) { dump_bmp(&per_cpu(ps3_private, 0)); dump_bmp(&per_cpu(ps3_private, 1)); BUG(); -- 2.39.5