From 916a0fe739f151664f7f07b42543ae6fd4caec49 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Mon, 8 Jun 2009 03:00:22 -0700 Subject: [PATCH] x86/ioapic.c: remove #ifdef for 82093AA workaround While no 64-bit hardware will have a version 0x11 I/O APIC which needs the level/edge bug workaround, that's not a particular reason to use CONFIG_X86_32 to #ifdef the code out. Most 32-bit machines will no longer need the workaround either, so the test to see whether it is necessary should be more fine-grained than "32-bit=yes, 64-bit=no". (Also fix formatting of block comment.) Signed-off-by: Jeremy Fitzhardinge --- arch/x86/kernel/apic/io_apic.c | 47 ++++++++++++++-------------------- 1 file changed, 19 insertions(+), 28 deletions(-) diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index f8aa5461071b..1a3414442583 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -596,7 +596,6 @@ static void __mask_IO_APIC_irq(struct irq_cfg *cfg) io_apic_modify_irq(cfg, ~0, IO_APIC_REDIR_MASKED, &io_apic_sync); } -#ifdef CONFIG_X86_32 static void __mask_and_edge_IO_APIC_irq(struct irq_cfg *cfg) { io_apic_modify_irq(cfg, ~IO_APIC_REDIR_LEVEL_TRIGGER, @@ -608,7 +607,6 @@ static void __unmask_and_level_IO_APIC_irq(struct irq_cfg *cfg) io_apic_modify_irq(cfg, ~IO_APIC_REDIR_MASKED, IO_APIC_REDIR_LEVEL_TRIGGER, NULL); } -#endif /* CONFIG_X86_32 */ static void mask_IO_APIC_irq_desc(struct irq_desc *desc) { @@ -2510,11 +2508,8 @@ atomic_t irq_mis_count; static void ack_apic_level(unsigned int irq) { struct irq_desc *desc = irq_to_desc(irq); - -#ifdef CONFIG_X86_32 unsigned long v; int i; -#endif struct irq_cfg *cfg; int do_unmask_irq = 0; @@ -2527,31 +2522,28 @@ static void ack_apic_level(unsigned int irq) } #endif -#ifdef CONFIG_X86_32 /* - * It appears there is an erratum which affects at least version 0x11 - * of I/O APIC (that's the 82093AA and cores integrated into various - * chipsets). Under certain conditions a level-triggered interrupt is - * erroneously delivered as edge-triggered one but the respective IRR - * bit gets set nevertheless. As a result the I/O unit expects an EOI - * message but it will never arrive and further interrupts are blocked - * from the source. The exact reason is so far unknown, but the - * phenomenon was observed when two consecutive interrupt requests - * from a given source get delivered to the same CPU and the source is - * temporarily disabled in between. - * - * A workaround is to simulate an EOI message manually. We achieve it - * by setting the trigger mode to edge and then to level when the edge - * trigger mode gets detected in the TMR of a local APIC for a - * level-triggered interrupt. We mask the source for the time of the - * operation to prevent an edge-triggered interrupt escaping meanwhile. - * The idea is from Manfred Spraul. --macro - */ + * It appears there is an erratum which affects at least version 0x11 + * of I/O APIC (that's the 82093AA and cores integrated into various + * chipsets). Under certain conditions a level-triggered interrupt is + * erroneously delivered as edge-triggered one but the respective IRR + * bit gets set nevertheless. As a result the I/O unit expects an EOI + * message but it will never arrive and further interrupts are blocked + * from the source. The exact reason is so far unknown, but the + * phenomenon was observed when two consecutive interrupt requests + * from a given source get delivered to the same CPU and the source is + * temporarily disabled in between. + * + * A workaround is to simulate an EOI message manually. We achieve it + * by setting the trigger mode to edge and then to level when the edge + * trigger mode gets detected in the TMR of a local APIC for a + * level-triggered interrupt. We mask the source for the time of the + * operation to prevent an edge-triggered interrupt escaping meanwhile. + * The idea is from Manfred Spraul. --macro + */ cfg = desc->chip_data; i = cfg->vector; - v = apic_read(APIC_TMR + ((i & ~0x1f) >> 1)); -#endif /* * We must acknowledge the irq before we move it or the acknowledge will @@ -2593,7 +2585,7 @@ static void ack_apic_level(unsigned int irq) unmask_IO_APIC_irq_desc(desc); } -#ifdef CONFIG_X86_32 + /* Tail end of version 0x11 I/O APIC bug workaround */ if (!(v & (1 << (i & 0x1f)))) { atomic_inc(&irq_mis_count); spin_lock(&ioapic_lock); @@ -2601,7 +2593,6 @@ static void ack_apic_level(unsigned int irq) __unmask_and_level_IO_APIC_irq(cfg); spin_unlock(&ioapic_lock); } -#endif } #ifdef CONFIG_INTR_REMAP -- 2.34.1