[IA64] SN: Add support for CPU disable
Add additional support for CPU disable on SN platforms.
Correctly setup the smp_affinity mask for I/O error IRQs.
Restrict the use of the feature to Altix 4000 and 450 systems
running with a CPU disable capable PROM, and do not allow disabling
of CPU 0.
Signed-off-by: John Keller <jpk@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
diff --git a/arch/ia64/sn/kernel/irq.c b/arch/ia64/sn/kernel/irq.c
index 3600473..0f9b126 100644
--- a/arch/ia64/sn/kernel/irq.c
+++ b/arch/ia64/sn/kernel/irq.c
@@ -19,6 +19,7 @@
#include <asm/sn/pcidev.h>
#include <asm/sn/shub_mmr.h>
#include <asm/sn/sn_sal.h>
+#include <asm/sn/sn_feature_sets.h>
static void force_interrupt(int irq);
static void register_intr_pda(struct sn_irq_info *sn_irq_info);
@@ -233,6 +234,20 @@
(void)sn_retarget_vector(sn_irq_info, nasid, slice);
}
+#ifdef CONFIG_SMP
+void sn_set_err_irq_affinity(unsigned int irq)
+{
+ /*
+ * On systems which support CPU disabling (SHub2), all error interrupts
+ * are targetted at the boot CPU.
+ */
+ if (is_shub2() && sn_prom_feature_available(PRF_CPU_DISABLE_SUPPORT))
+ set_irq_affinity_info(irq, cpu_physical_id(0), 0);
+}
+#else
+void sn_set_err_irq_affinity(unsigned int irq) { }
+#endif
+
static void
sn_mask_irq(unsigned int irq)
{