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-rw-r--r--arch/mn10300/kernel/irq.c71
-rw-r--r--arch/mn10300/kernel/time.c52
-rw-r--r--arch/mn10300/unit-asb2303/unit-init.c2
-rw-r--r--arch/mn10300/unit-asb2305/unit-init.c2
4 files changed, 88 insertions, 39 deletions
diff --git a/arch/mn10300/kernel/irq.c b/arch/mn10300/kernel/irq.c
index 761c434a248..56c64ccc9c2 100644
--- a/arch/mn10300/kernel/irq.c
+++ b/arch/mn10300/kernel/irq.c
@@ -20,22 +20,8 @@ EXPORT_SYMBOL(__mn10300_irq_enabled_epsw);
atomic_t irq_err_count;
/*
- * MN10300 INTC controller operations
+ * MN10300 interrupt controller operations
*/
-static void mn10300_cpupic_disable(unsigned int irq)
-{
- u16 tmp = GxICR(irq);
- GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_DETECT;
- tmp = GxICR(irq);
-}
-
-static void mn10300_cpupic_enable(unsigned int irq)
-{
- u16 tmp = GxICR(irq);
- GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_ENABLE;
- tmp = GxICR(irq);
-}
-
static void mn10300_cpupic_ack(unsigned int irq)
{
u16 tmp;
@@ -60,26 +46,54 @@ static void mn10300_cpupic_mask_ack(unsigned int irq)
static void mn10300_cpupic_unmask(unsigned int irq)
{
u16 tmp = GxICR(irq);
- GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_ENABLE | GxICR_DETECT;
+ GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_ENABLE;
tmp = GxICR(irq);
}
-static void mn10300_cpupic_end(unsigned int irq)
+static void mn10300_cpupic_unmask_clear(unsigned int irq)
{
+ /* the MN10300 PIC latches its interrupt request bit, even after the
+ * device has ceased to assert its interrupt line and the interrupt
+ * channel has been disabled in the PIC, so for level-triggered
+ * interrupts we need to clear the request bit when we re-enable */
u16 tmp = GxICR(irq);
- GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_ENABLE;
+ GxICR(irq) = (tmp & GxICR_LEVEL) | GxICR_ENABLE | GxICR_DETECT;
tmp = GxICR(irq);
}
-static struct irq_chip mn10300_cpu_pic = {
- .name = "cpu",
- .disable = mn10300_cpupic_disable,
- .enable = mn10300_cpupic_enable,
+/*
+ * MN10300 PIC level-triggered IRQ handling.
+ *
+ * The PIC has no 'ACK' function per se. It is possible to clear individual
+ * channel latches, but each latch relatches whether or not the channel is
+ * masked, so we need to clear the latch when we unmask the channel.
+ *
+ * Also for this reason, we don't supply an ack() op (it's unused anyway if
+ * mask_ack() is provided), and mask_ack() just masks.
+ */
+static struct irq_chip mn10300_cpu_pic_level = {
+ .name = "cpu_l",
+ .disable = mn10300_cpupic_mask,
+ .enable = mn10300_cpupic_unmask_clear,
+ .ack = NULL,
+ .mask = mn10300_cpupic_mask,
+ .mask_ack = mn10300_cpupic_mask,
+ .unmask = mn10300_cpupic_unmask_clear,
+};
+
+/*
+ * MN10300 PIC edge-triggered IRQ handling.
+ *
+ * We use the latch clearing function of the PIC as the 'ACK' function.
+ */
+static struct irq_chip mn10300_cpu_pic_edge = {
+ .name = "cpu_e",
+ .disable = mn10300_cpupic_mask,
+ .enable = mn10300_cpupic_unmask,
.ack = mn10300_cpupic_ack,
.mask = mn10300_cpupic_mask,
.mask_ack = mn10300_cpupic_mask_ack,
.unmask = mn10300_cpupic_unmask,
- .end = mn10300_cpupic_end,
};
/*
@@ -114,7 +128,8 @@ void set_intr_level(int irq, u16 level)
*/
void set_intr_postackable(int irq)
{
- set_irq_handler(irq, handle_level_irq);
+ set_irq_chip_and_handler(irq, &mn10300_cpu_pic_level,
+ handle_level_irq);
}
/*
@@ -126,8 +141,12 @@ void __init init_IRQ(void)
for (irq = 0; irq < NR_IRQS; irq++)
if (irq_desc[irq].chip == &no_irq_type)
- set_irq_chip_and_handler(irq, &mn10300_cpu_pic,
- handle_edge_irq);
+ /* due to the PIC latching interrupt requests, even
+ * when the IRQ is disabled, IRQ_PENDING is superfluous
+ * and we can use handle_level_irq() for edge-triggered
+ * interrupts */
+ set_irq_chip_and_handler(irq, &mn10300_cpu_pic_edge,
+ handle_level_irq);
unit_init_IRQ();
}
diff --git a/arch/mn10300/kernel/time.c b/arch/mn10300/kernel/time.c
index babb7c2ac37..e4606586f94 100644
--- a/arch/mn10300/kernel/time.c
+++ b/arch/mn10300/kernel/time.c
@@ -1,6 +1,6 @@
/* MN10300 Low level time management
*
- * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Copyright (C) 2007-2008 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
* - Derived from arch/i386/kernel/time.c
*
@@ -16,6 +16,7 @@
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/profile.h>
+#include <linux/cnt32_to_63.h>
#include <asm/irq.h>
#include <asm/div64.h>
#include <asm/processor.h>
@@ -40,27 +41,54 @@ static struct irqaction timer_irq = {
.name = "timer",
};
+static unsigned long sched_clock_multiplier;
+
/*
* scheduler clock - returns current time in nanosec units.
*/
unsigned long long sched_clock(void)
{
union {
- unsigned long long l;
- u32 w[2];
- } quot;
+ unsigned long long ll;
+ unsigned l[2];
+ } tsc64, result;
+ unsigned long tsc, tmp;
+ unsigned product[3]; /* 96-bit intermediate value */
+
+ /* read the TSC value
+ */
+ tsc = 0 - get_cycles(); /* get_cycles() counts down */
- quot.w[0] = mn10300_last_tsc - get_cycles();
- quot.w[1] = 1000000000;
+ /* expand to 64-bits.
+ * - sched_clock() must be called once a minute or better or the
+ * following will go horribly wrong - see cnt32_to_63()
+ */
+ tsc64.ll = cnt32_to_63(tsc) & 0x7fffffffffffffffULL;
- asm("mulu %2,%3,%0,%1"
- : "=r"(quot.w[1]), "=r"(quot.w[0])
- : "0"(quot.w[1]), "1"(quot.w[0])
+ /* scale the 64-bit TSC value to a nanosecond value via a 96-bit
+ * intermediate
+ */
+ asm("mulu %2,%0,%3,%0 \n" /* LSW * mult -> 0:%3:%0 */
+ "mulu %2,%1,%2,%1 \n" /* MSW * mult -> %2:%1:0 */
+ "add %3,%1 \n"
+ "addc 0,%2 \n" /* result in %2:%1:%0 */
+ : "=r"(product[0]), "=r"(product[1]), "=r"(product[2]), "=r"(tmp)
+ : "0"(tsc64.l[0]), "1"(tsc64.l[1]), "2"(sched_clock_multiplier)
: "cc");
- do_div(quot.l, MN10300_TSCCLK);
+ result.l[0] = product[1] << 16 | product[0] >> 16;
+ result.l[1] = product[2] << 16 | product[1] >> 16;
- return quot.l;
+ return result.ll;
+}
+
+/*
+ * initialise the scheduler clock
+ */
+static void __init mn10300_sched_clock_init(void)
+{
+ sched_clock_multiplier =
+ __muldiv64u(NSEC_PER_SEC, 1 << 16, MN10300_TSCCLK);
}
/*
@@ -128,4 +156,6 @@ void __init time_init(void)
/* start the watchdog timer */
watchdog_go();
#endif
+
+ mn10300_sched_clock_init();
}
diff --git a/arch/mn10300/unit-asb2303/unit-init.c b/arch/mn10300/unit-asb2303/unit-init.c
index 14b2c817cff..70e8cb4ea26 100644
--- a/arch/mn10300/unit-asb2303/unit-init.c
+++ b/arch/mn10300/unit-asb2303/unit-init.c
@@ -51,7 +51,7 @@ void __init unit_init_IRQ(void)
switch (GET_XIRQ_TRIGGER(extnum)) {
case XIRQ_TRIGGER_HILEVEL:
case XIRQ_TRIGGER_LOWLEVEL:
- set_irq_handler(XIRQ2IRQ(extnum), handle_level_irq);
+ set_intr_postackable(XIRQ2IRQ(extnum));
break;
default:
break;
diff --git a/arch/mn10300/unit-asb2305/unit-init.c b/arch/mn10300/unit-asb2305/unit-init.c
index 6a352414a35..72812a9439a 100644
--- a/arch/mn10300/unit-asb2305/unit-init.c
+++ b/arch/mn10300/unit-asb2305/unit-init.c
@@ -52,7 +52,7 @@ void __init unit_init_IRQ(void)
switch (GET_XIRQ_TRIGGER(extnum)) {
case XIRQ_TRIGGER_HILEVEL:
case XIRQ_TRIGGER_LOWLEVEL:
- set_irq_handler(XIRQ2IRQ(extnum), handle_level_irq);
+ set_intr_postackable(XIRQ2IRQ(extnum));
break;
default:
break;
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-01 04:42:00 +0000