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Diffstat (limited to 'arch/sparc/kernel/sun4c_irq.c')
-rw-r--r--arch/sparc/kernel/sun4c_irq.c81
1 files changed, 44 insertions, 37 deletions
diff --git a/arch/sparc/kernel/sun4c_irq.c b/arch/sparc/kernel/sun4c_irq.c
index 892fb884910a..f543b452ebc1 100644
--- a/arch/sparc/kernel/sun4c_irq.c
+++ b/arch/sparc/kernel/sun4c_irq.c
@@ -1,5 +1,5 @@
-/* sun4c_irq.c
- * arch/sparc/kernel/sun4c_irq.c:
+/*
+ * sun4c irq support
*
* djhr: Hacked out of irq.c into a CPU dependent version.
*
@@ -9,31 +9,41 @@
* Copyright (C) 1996 Dave Redman (djhr@tadpole.co.uk)
*/
-#include <linux/errno.h>
-#include <linux/linkage.h>
-#include <linux/kernel_stat.h>
-#include <linux/signal.h>
-#include <linux/sched.h>
-#include <linux/ptrace.h>
-#include <linux/interrupt.h>
#include <linux/init.h>
-#include <linux/of.h>
-#include <linux/of_device.h>
-#include "irq.h"
-#include <asm/ptrace.h>
-#include <asm/processor.h>
-#include <asm/system.h>
-#include <asm/psr.h>
-#include <asm/vaddrs.h>
-#include <asm/timer.h>
-#include <asm/openprom.h>
#include <asm/oplib.h>
-#include <asm/traps.h>
+#include <asm/timer.h>
#include <asm/irq.h>
#include <asm/io.h>
-#include <asm/idprom.h>
-#include <asm/machines.h>
+
+#include "irq.h"
+
+/* Sun4c interrupts are typically laid out as follows:
+ *
+ * 1 - Software interrupt, SBUS level 1
+ * 2 - SBUS level 2
+ * 3 - ESP SCSI, SBUS level 3
+ * 4 - Software interrupt
+ * 5 - Lance ethernet, SBUS level 4
+ * 6 - Software interrupt
+ * 7 - Graphics card, SBUS level 5
+ * 8 - SBUS level 6
+ * 9 - SBUS level 7
+ * 10 - Counter timer
+ * 11 - Floppy
+ * 12 - Zilog uart
+ * 13 - CS4231 audio
+ * 14 - Profiling timer
+ * 15 - NMI
+ *
+ * The interrupt enable bits in the interrupt mask register are
+ * really only used to enable/disable the timer interrupts, and
+ * for signalling software interrupts. There is also a master
+ * interrupt enable bit in this register.
+ *
+ * Interrupts are enabled by setting the SUN4C_INT_* bits, they
+ * are disabled by clearing those bits.
+ */
/*
* Bit field defines for the interrupt registers on various
@@ -49,26 +59,21 @@
#define SUN4C_INT_E4 0x04 /* Enable level 4 IRQ. */
#define SUN4C_INT_E1 0x02 /* Enable level 1 IRQ. */
-/* Pointer to the interrupt enable byte
- *
- * Dave Redman (djhr@tadpole.co.uk)
- * What you may not be aware of is that entry.S requires this variable.
- *
- * --- linux_trap_nmi_sun4c --
- *
- * so don't go making it static, like I tried. sigh.
+/*
+ * Pointer to the interrupt enable byte
+ * Used by entry.S
*/
-unsigned char __iomem *interrupt_enable = NULL;
+unsigned char __iomem *interrupt_enable;
static void sun4c_disable_irq(unsigned int irq_nr)
{
unsigned long flags;
unsigned char current_mask, new_mask;
-
+
local_irq_save(flags);
irq_nr &= (NR_IRQS - 1);
current_mask = sbus_readb(interrupt_enable);
- switch(irq_nr) {
+ switch (irq_nr) {
case 1:
new_mask = ((current_mask) & (~(SUN4C_INT_E1)));
break;
@@ -93,11 +98,11 @@ static void sun4c_enable_irq(unsigned int irq_nr)
{
unsigned long flags;
unsigned char current_mask, new_mask;
-
+
local_irq_save(flags);
irq_nr &= (NR_IRQS - 1);
current_mask = sbus_readb(interrupt_enable);
- switch(irq_nr) {
+ switch (irq_nr) {
case 1:
new_mask = ((current_mask) | SUN4C_INT_E1);
break;
@@ -180,12 +185,14 @@ static void __init sun4c_init_timers(irq_handler_t counter_fn)
prom_printf("sun4c_init_timers: request_irq() fails with %d\n", err);
prom_halt();
}
-
+
sun4c_disable_irq(irq[1].pri);
}
#ifdef CONFIG_SMP
-static void sun4c_nop(void) {}
+static void sun4c_nop(void)
+{
+}
#endif
void __init sun4c_init_IRQ(void)