[PATCH v2] microblaze: Change NO_IRQ to 0
Michal Simek
monstr at monstr.eu
Tue Dec 20 01:19:54 EST 2011
As has been discussed many times[1], Using NO_IRQ set to anything other
than 0 is bug waiting to happen since many drivers follow the pattern
"if (!irq)" for testing whether or not an irq has been set.
This patch changes the Microblaze NO_IRQ setting from -1 to 0 to bring
it in line with most of the rest of the kernel. It also prepares for
Microblaze eventually supporting multiple interrupt controllers by
breaking the assumption that hwirq# == Linux IRQ#. The Linux IRQ
number is just a cookie with no guarantee of a direct relationship
with the hardware irq arrangement.
At this point, Microblaze interrupt handling only supports only one
instance of one kind of interrupt controller (xilinx_intc). This change
shouldn't affect any architecture code outside of the interrupt
controller driver and the irq_of mapping.
Updated to 3.2 and to use irq_data.hwirq by Rob Herring.
Tested and fixed by Michal Simek.
[1] http://lkml.org/lkml/2005/11/21/221
Signed-off-by: Grant Likely <grant.likely at secretlab.ca>
Signed-off-by: Rob Herring <rob.herring at calxeda.com>
Signed-off-by: Michal Simek <monstr at monstr.eu>
---
v2: Use NO_/IRQ_OFFSET and not to use hardcoded numbers.
Keep option to be able to break assumption that hwirq# == Linux IRQ#
---
arch/microblaze/include/asm/irq.h | 11 +++++++++--
arch/microblaze/kernel/intc.c | 28 +++++++++++++++-------------
arch/microblaze/kernel/irq.c | 11 ++++++-----
3 files changed, 30 insertions(+), 20 deletions(-)
diff --git a/arch/microblaze/include/asm/irq.h b/arch/microblaze/include/asm/irq.h
index cc54187..b116a82 100644
--- a/arch/microblaze/include/asm/irq.h
+++ b/arch/microblaze/include/asm/irq.h
@@ -9,7 +9,14 @@
#ifndef _ASM_MICROBLAZE_IRQ_H
#define _ASM_MICROBLAZE_IRQ_H
-#define NR_IRQS 32
+
+/*
+ * Linux IRQ# is currently offset by one to map to the hardware
+ * irq number. So hardware IRQ0 maps to Linux irq 1.
+ */
+#define NO_IRQ_OFFSET 1
+#define IRQ_OFFSET NO_IRQ_OFFSET
+#define NR_IRQS (32 + IRQ_OFFSET)
#include <asm-generic/irq.h>
/* This type is the placeholder for a hardware interrupt number. It has to
@@ -20,7 +27,7 @@ typedef unsigned long irq_hw_number_t;
extern unsigned int nr_irq;
-#define NO_IRQ (-1)
+#define NO_IRQ 0
struct pt_regs;
extern void do_IRQ(struct pt_regs *regs);
diff --git a/arch/microblaze/kernel/intc.c b/arch/microblaze/kernel/intc.c
index 1293098..44b177e 100644
--- a/arch/microblaze/kernel/intc.c
+++ b/arch/microblaze/kernel/intc.c
@@ -42,8 +42,9 @@ unsigned int nr_irq;
static void intc_enable_or_unmask(struct irq_data *d)
{
- unsigned long mask = 1 << d->irq;
- pr_debug("enable_or_unmask: %d\n", d->irq);
+ unsigned long mask = 1 << d->hwirq;
+
+ pr_debug("enable_or_unmask: %ld\n", d->hwirq);
out_be32(INTC_BASE + SIE, mask);
/* ack level irqs because they can't be acked during
@@ -56,20 +57,21 @@ static void intc_enable_or_unmask(struct irq_data *d)
static void intc_disable_or_mask(struct irq_data *d)
{
- pr_debug("disable: %d\n", d->irq);
- out_be32(INTC_BASE + CIE, 1 << d->irq);
+ pr_debug("disable: %ld\n", d->hwirq);
+ out_be32(INTC_BASE + CIE, 1 << d->hwirq);
}
static void intc_ack(struct irq_data *d)
{
- pr_debug("ack: %d\n", d->irq);
- out_be32(INTC_BASE + IAR, 1 << d->irq);
+ pr_debug("ack: %ld\n", d->hwirq);
+ out_be32(INTC_BASE + IAR, 1 << d->hwirq);
}
static void intc_mask_ack(struct irq_data *d)
{
- unsigned long mask = 1 << d->irq;
- pr_debug("disable_and_ack: %d\n", d->irq);
+ unsigned long mask = 1 << d->hwirq;
+
+ pr_debug("disable_and_ack: %ld\n", d->hwirq);
out_be32(INTC_BASE + CIE, mask);
out_be32(INTC_BASE + IAR, mask);
}
@@ -91,7 +93,7 @@ unsigned int get_irq(struct pt_regs *regs)
* order to handle multiple interrupt controllers. It currently
* is hardcoded to check for interrupts only on the first INTC.
*/
- irq = in_be32(INTC_BASE + IVR);
+ irq = in_be32(INTC_BASE + IVR) + NO_IRQ_OFFSET;
pr_debug("get_irq: %d\n", irq);
return irq;
@@ -116,8 +118,7 @@ void __init init_IRQ(void)
intc = of_find_compatible_node(NULL, NULL, "xlnx,xps-intc-1.00.a");
BUG_ON(!intc);
- intc_baseaddr = be32_to_cpup(of_get_property(intc,
- "reg", NULL));
+ intc_baseaddr = be32_to_cpup(of_get_property(intc, "reg", NULL));
intc_baseaddr = (unsigned long) ioremap(intc_baseaddr, PAGE_SIZE);
nr_irq = be32_to_cpup(of_get_property(intc,
"xlnx,num-intr-inputs", NULL));
@@ -145,8 +146,8 @@ void __init init_IRQ(void)
/* Turn on the Master Enable. */
out_be32(intc_baseaddr + MER, MER_HIE | MER_ME);
- for (i = 0; i < nr_irq; ++i) {
- if (intr_mask & (0x00000001 << i)) {
+ for (i = IRQ_OFFSET; i < (nr_irq + IRQ_OFFSET); ++i) {
+ if (intr_mask & (0x00000001 << (i - IRQ_OFFSET))) {
irq_set_chip_and_handler_name(i, &intc_dev,
handle_edge_irq, "edge");
irq_clear_status_flags(i, IRQ_LEVEL);
@@ -155,5 +156,6 @@ void __init init_IRQ(void)
handle_level_irq, "level");
irq_set_status_flags(i, IRQ_LEVEL);
}
+ irq_get_irq_data(i)->hwirq = i - IRQ_OFFSET;
}
}
diff --git a/arch/microblaze/kernel/irq.c b/arch/microblaze/kernel/irq.c
index e5d63a8..bbebcae 100644
--- a/arch/microblaze/kernel/irq.c
+++ b/arch/microblaze/kernel/irq.c
@@ -33,11 +33,12 @@ void __irq_entry do_IRQ(struct pt_regs *regs)
irq_enter();
irq = get_irq(regs);
next_irq:
- BUG_ON(irq == -1U);
- generic_handle_irq(irq);
+ BUG_ON(!irq);
+ /* Substract 1 because of get_irq */
+ generic_handle_irq(irq + IRQ_OFFSET - NO_IRQ_OFFSET);
irq = get_irq(regs);
- if (irq != -1U) {
+ if (irq) {
pr_debug("next irq: %d\n", irq);
++concurrent_irq;
goto next_irq;
@@ -52,13 +53,13 @@ next_irq:
intc without any cascades or any connection that's why mapping is 1:1 */
unsigned int irq_create_mapping(struct irq_host *host, irq_hw_number_t hwirq)
{
- return hwirq;
+ return hwirq + IRQ_OFFSET;
}
EXPORT_SYMBOL_GPL(irq_create_mapping);
unsigned int irq_create_of_mapping(struct device_node *controller,
const u32 *intspec, unsigned int intsize)
{
- return intspec[0];
+ return intspec[0] + IRQ_OFFSET;
}
EXPORT_SYMBOL_GPL(irq_create_of_mapping);
--
1.7.5.4
More information about the devicetree-discuss
mailing list