Introduce a standard name for the lock protecting an interrupt controller

and it's associated state variables: icu_lock with the name "icu".  This
renames the imen_mtx for x86 SMP, but also uses the lock to protect
access to the 8259 PIC on x86 UP.  This also adds an appropriate lock to
the various Alpha chipsets which fixes problems with Alpha SMP machines
dropping interrupts with an SMP kernel.

4 files changed, 55 insertions, 10 deletions

diff --git a/sys/alpha/pci/apecs.c b/sys/alpha/pci/apecs.c
index ebe350b..c74e940 100644
--- a/sys/alpha/pci/apecs.c
+++ b/sys/alpha/pci/apecs.c
@@ -58,8 +58,10 @@
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/kernel.h>
-#include <sys/module.h>
+#include <sys/lock.h>
 #include <sys/malloc.h>
+#include <sys/module.h>
+#include <sys/mutex.h>
 #include <sys/bus.h>
 #include <machine/bus.h>
 #include <sys/proc.h>
@@ -304,15 +306,23 @@ apecs_attach(device_t dev)
 static void
 apecs_disable_intr(int vector)
 {
-	int irq = (vector - 0x900) >> 4;
+	int irq;
+
+	irq = (vector - 0x900) >> 4;
+	mtx_lock_spin(&icu_lock);
 	platform.pci_intr_disable(irq);
+	mtx_unlock_spin(&icu_lock);
 }
 
 static void
 apecs_enable_intr(int vector)
 {
-	int irq = (vector - 0x900) >> 4;
+	int irq;
+
+	irq = (vector - 0x900) >> 4;
+	mtx_lock_spin(&icu_lock);
 	platform.pci_intr_enable(irq);
+	mtx_unlock_spin(&icu_lock);
 }
 
 static int
@@ -342,7 +352,9 @@ apecs_setup_intr(device_t dev, device_t child,
 		return error;
 
 	/* Enable PCI interrupt */
+	mtx_lock_spin(&icu_lock);
 	platform.pci_intr_enable(irq->r_start);
+	mtx_unlock_spin(&icu_lock);
 
 	device_printf(child, "interrupting at APECS irq %d\n",
 		      (int) irq->r_start);
diff --git a/sys/alpha/pci/cia.c b/sys/alpha/pci/cia.c
index 09436e3..40f205c 100644
--- a/sys/alpha/pci/cia.c
+++ b/sys/alpha/pci/cia.c
@@ -94,8 +94,10 @@
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/kernel.h>
-#include <sys/module.h>
+#include <sys/lock.h>
 #include <sys/malloc.h>
+#include <sys/module.h>
+#include <sys/mutex.h>
 #include <sys/bus.h>
 #include <machine/bus.h>
 #include <sys/proc.h>
@@ -513,15 +515,23 @@ cia_attach(device_t dev)
 static void
 cia_disable_intr(int vector)
 {
-	int irq = (vector - 0x900) >> 4;
+	int irq;
+
+	irq = (vector - 0x900) >> 4;
+	mtx_lock_spin(&icu_lock);
 	platform.pci_intr_disable(irq);
+	mtx_unlock_spin(&icu_lock);
 }
 
 static void
 cia_enable_intr(int vector)
 {
-	int irq = (vector - 0x900) >> 4;
+	int irq;
+
+	irq = (vector - 0x900) >> 4;
+	mtx_lock_spin(&icu_lock);
 	platform.pci_intr_enable(irq);
+	mtx_unlock_spin(&icu_lock);
 }
 
 static int
@@ -544,7 +554,9 @@ cia_setup_intr(device_t dev, device_t child,
 		return error;
 
 	/* Enable PCI interrupt */
+	mtx_lock_spin(&icu_lock);
 	platform.pci_intr_enable(irq->r_start);
+	mtx_unlock_spin(&icu_lock);
 
 	device_printf(child, "interrupting at CIA irq %d\n",
 		      (int) irq->r_start);
diff --git a/sys/alpha/pci/t2.c b/sys/alpha/pci/t2.c
index d9d0b9d..3dcfe35 100644
--- a/sys/alpha/pci/t2.c
+++ b/sys/alpha/pci/t2.c
@@ -55,8 +55,10 @@
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/kernel.h>
-#include <sys/module.h>
+#include <sys/lock.h>
 #include <sys/malloc.h>
+#include <sys/module.h>
+#include <sys/mutex.h>
 #include <sys/bus.h>
 #include <machine/bus.h>
 #include <sys/proc.h>
@@ -460,6 +462,7 @@ t2_enable_vec(int vector)
 	hose = (vector >= 0xC00);
 	irq = (vector - 0x800) >> 4;
 
+	mtx_lock_spin(&icu_lock);
 	if (pci_int_type[hose]) {
 
 		/* Write the air register on the T3/T4 with the
@@ -481,6 +484,7 @@ t2_enable_vec(int vector)
 		/* Old style 8259 (Gack!!!) interrupts */
 		t2_8259_enable_mask(irq);
 	}
+	mtx_unlock_spin(&icu_lock);
 }
 
 static void
@@ -492,6 +496,7 @@ t2_disable_vec(int vector)
 	hose = (vector >= 0xC00);
 	irq =  (vector - 0x800) >> 4;
 
+	mtx_lock_spin(&icu_lock);
 	if (pci_int_type[hose]) {
 
 		/* Write the air register on the T3/T4 wioth the
@@ -515,6 +520,7 @@ t2_disable_vec(int vector)
 		/* Old style 8259 (Gack!!!) interrupts */
 		t2_8259_disable_mask(irq);
 	}
+	mtx_unlock_spin(&icu_lock);
 }
 
 
@@ -590,12 +596,14 @@ t2_teardown_intr(device_t dev, device_t child,
 
 	t2_shadow_mask |= (1UL << mask);
 
+	mtx_lock_spin(&icu_lock);
 	if (mask <= 7)
 		outb(SLAVE0_ICU, t2_shadow_mask);
 	else if (mask <= 15)
 		outb(SLAVE1_ICU, t2_shadow_mask >> 8);
 	else 
 		outb(SLAVE2_ICU, t2_shadow_mask >> 16);
+	mtx_unlock_spin(&icu_lock);
 
 	alpha_teardown_intr(cookie);
 	return rman_deactivate_resource(irq);
@@ -607,7 +615,9 @@ static void
 t2_dispatch_intr(void *frame, unsigned long vector)
 {
 	alpha_dispatch_intr(frame, vector);
+	mtx_lock_spin(&icu_lock);
 	t2_eoi(vector);
+	mtx_unlock_spin(&icu_lock);
 }
 
 static void
diff --git a/sys/alpha/pci/tsunami.c b/sys/alpha/pci/tsunami.c
index 1ca0803..3ca127b 100644
--- a/sys/alpha/pci/tsunami.c
+++ b/sys/alpha/pci/tsunami.c
@@ -31,7 +31,9 @@
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/kernel.h>
+#include <sys/lock.h>
 #include <sys/module.h>
+#include <sys/mutex.h>
 #include <sys/bus.h>
 #include <machine/bus.h>
 #include <sys/proc.h>
@@ -305,15 +307,23 @@ tsunami_attach(device_t dev)
 static void
 tsunami_disable_intr_vec(int vector)
 {
-	int irq = (vector - 0x900) >> 4;
+	int irq;
+
+	irq = (vector - 0x900) >> 4;
+	mtx_lock_spin(&icu_lock);
 	platform.pci_intr_disable(irq);
+	mtx_unlock_spin(&icu_lock);
 }
 
 static void
 tsunami_enable_intr_vec(int vector)
 {
-	int irq = (vector - 0x900) >> 4;
+	int irq;
+
+	irq = (vector - 0x900) >> 4;
+	mtx_lock_spin(&icu_lock);
 	platform.pci_intr_enable(irq);
+	mtx_unlock_spin(&icu_lock);
 }
 
 static int
@@ -335,7 +345,9 @@ tsunami_setup_intr(device_t dev, device_t child,
 		return error;
 
 	/* Enable PCI interrupt */
+	mtx_lock_spin(&icu_lock);
 	platform.pci_intr_enable(irq->r_start);
+	mtx_unlock_spin(&icu_lock);
 
 	device_printf(child, "interrupting at TSUNAMI irq %d\n",
 		      (int) irq->r_start);
@@ -391,7 +403,6 @@ tsunami_intr_disable(int irq)
 	saved_mask = *mask;
 	alpha_mb();
 	alpha_mb();
-
 }