xtensa: add IRQ domains support
IRQ domains provide a mechanism for conversion of linux IRQ numbers to
hardware IRQ numbers and vice versus. It is used by OpenFirmware for
linking device tree objects to their respective interrupt controllers.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index 2481f26..1816abc 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -17,6 +17,7 @@
select GENERIC_KERNEL_EXECVE
select ARCH_WANT_OPTIONAL_GPIOLIB
select CLONE_BACKWARDS
+ select IRQ_DOMAIN
help
Xtensa processors are 32-bit RISC machines designed by Tensilica
primarily for embedded systems. These processors are both
diff --git a/arch/xtensa/kernel/irq.c b/arch/xtensa/kernel/irq.c
index a6ce3e5..e90d782 100644
--- a/arch/xtensa/kernel/irq.c
+++ b/arch/xtensa/kernel/irq.c
@@ -18,6 +18,7 @@
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/kernel_stat.h>
+#include <linux/irqdomain.h>
#include <asm/uaccess.h>
#include <asm/platform.h>
@@ -26,19 +27,22 @@
atomic_t irq_err_count;
+static struct irq_domain *root_domain;
+
/*
* do_IRQ handles all normal device IRQ's (the special
* SMP cross-CPU interrupts have their own specific
* handlers).
*/
-asmlinkage void do_IRQ(int irq, struct pt_regs *regs)
+asmlinkage void do_IRQ(int hwirq, struct pt_regs *regs)
{
struct pt_regs *old_regs = set_irq_regs(regs);
+ int irq = irq_find_mapping(root_domain, hwirq);
- if (irq >= NR_IRQS) {
+ if (hwirq >= NR_IRQS) {
printk(KERN_EMERG "%s: cannot handle IRQ %d\n",
- __func__, irq);
+ __func__, hwirq);
}
irq_enter();
@@ -71,40 +75,39 @@
static void xtensa_irq_mask(struct irq_data *d)
{
- cached_irq_mask &= ~(1 << d->irq);
+ cached_irq_mask &= ~(1 << d->hwirq);
set_sr (cached_irq_mask, intenable);
}
static void xtensa_irq_unmask(struct irq_data *d)
{
- cached_irq_mask |= 1 << d->irq;
+ cached_irq_mask |= 1 << d->hwirq;
set_sr (cached_irq_mask, intenable);
}
static void xtensa_irq_enable(struct irq_data *d)
{
- variant_irq_enable(d->irq);
+ variant_irq_enable(d->hwirq);
xtensa_irq_unmask(d);
}
static void xtensa_irq_disable(struct irq_data *d)
{
xtensa_irq_mask(d);
- variant_irq_disable(d->irq);
+ variant_irq_disable(d->hwirq);
}
static void xtensa_irq_ack(struct irq_data *d)
{
- set_sr(1 << d->irq, intclear);
+ set_sr(1 << d->hwirq, intclear);
}
static int xtensa_irq_retrigger(struct irq_data *d)
{
- set_sr (1 << d->irq, INTSET);
+ set_sr(1 << d->hwirq, intset);
return 1;
}
-
static struct irq_chip xtensa_irq_chip = {
.name = "xtensa",
.irq_enable = xtensa_irq_enable,
@@ -115,37 +118,90 @@
.irq_retrigger = xtensa_irq_retrigger,
};
+static int xtensa_irq_map(struct irq_domain *d, unsigned int irq,
+ irq_hw_number_t hw)
+{
+ u32 mask = 1 << hw;
+
+ if (mask & XCHAL_INTTYPE_MASK_SOFTWARE) {
+ irq_set_chip_and_handler_name(irq, &xtensa_irq_chip,
+ handle_simple_irq, "level");
+ irq_set_status_flags(irq, IRQ_LEVEL);
+ } else if (mask & XCHAL_INTTYPE_MASK_EXTERN_EDGE) {
+ irq_set_chip_and_handler_name(irq, &xtensa_irq_chip,
+ handle_edge_irq, "edge");
+ irq_clear_status_flags(irq, IRQ_LEVEL);
+ } else if (mask & XCHAL_INTTYPE_MASK_EXTERN_LEVEL) {
+ irq_set_chip_and_handler_name(irq, &xtensa_irq_chip,
+ handle_level_irq, "level");
+ irq_set_status_flags(irq, IRQ_LEVEL);
+ } else if (mask & XCHAL_INTTYPE_MASK_TIMER) {
+ irq_set_chip_and_handler_name(irq, &xtensa_irq_chip,
+ handle_edge_irq, "edge");
+ irq_clear_status_flags(irq, IRQ_LEVEL);
+ } else {/* XCHAL_INTTYPE_MASK_WRITE_ERROR */
+ /* XCHAL_INTTYPE_MASK_NMI */
+
+ irq_set_chip_and_handler_name(irq, &xtensa_irq_chip,
+ handle_level_irq, "level");
+ irq_set_status_flags(irq, IRQ_LEVEL);
+ }
+ return 0;
+}
+
+static unsigned map_ext_irq(unsigned ext_irq)
+{
+ unsigned mask = XCHAL_INTTYPE_MASK_EXTERN_EDGE |
+ XCHAL_INTTYPE_MASK_EXTERN_LEVEL;
+ unsigned i;
+
+ for (i = 0; mask; ++i, mask >>= 1) {
+ if ((mask & 1) && ext_irq-- == 0)
+ return i;
+ }
+ return XCHAL_NUM_INTERRUPTS;
+}
+
+/*
+ * Device Tree IRQ specifier translation function which works with one or
+ * two cell bindings. First cell value maps directly to the hwirq number.
+ * Second cell if present specifies whether hwirq number is external (1) or
+ * internal (0).
+ */
+int xtensa_irq_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
+ const u32 *intspec, unsigned int intsize,
+ unsigned long *out_hwirq, unsigned int *out_type)
+{
+ if (WARN_ON(intsize < 1 || intsize > 2))
+ return -EINVAL;
+ if (intsize == 2 && intspec[1] == 1) {
+ unsigned int_irq = map_ext_irq(intspec[0]);
+ if (int_irq < XCHAL_NUM_INTERRUPTS)
+ *out_hwirq = int_irq;
+ else
+ return -EINVAL;
+ } else {
+ *out_hwirq = intspec[0];
+ }
+ *out_type = IRQ_TYPE_NONE;
+ return 0;
+}
+
+static const struct irq_domain_ops xtensa_irq_domain_ops = {
+ .xlate = xtensa_irq_domain_xlate,
+ .map = xtensa_irq_map,
+};
+
void __init init_IRQ(void)
{
- int index;
-
- for (index = 0; index < XTENSA_NR_IRQS; index++) {
- int mask = 1 << index;
-
- if (mask & XCHAL_INTTYPE_MASK_SOFTWARE)
- irq_set_chip_and_handler(index, &xtensa_irq_chip,
- handle_simple_irq);
-
- else if (mask & XCHAL_INTTYPE_MASK_EXTERN_EDGE)
- irq_set_chip_and_handler(index, &xtensa_irq_chip,
- handle_edge_irq);
-
- else if (mask & XCHAL_INTTYPE_MASK_EXTERN_LEVEL)
- irq_set_chip_and_handler(index, &xtensa_irq_chip,
- handle_level_irq);
-
- else if (mask & XCHAL_INTTYPE_MASK_TIMER)
- irq_set_chip_and_handler(index, &xtensa_irq_chip,
- handle_edge_irq);
-
- else /* XCHAL_INTTYPE_MASK_WRITE_ERROR */
- /* XCHAL_INTTYPE_MASK_NMI */
-
- irq_set_chip_and_handler(index, &xtensa_irq_chip,
- handle_level_irq);
- }
+ struct device_node *intc = NULL;
cached_irq_mask = 0;
+ set_sr(~0, intclear);
+
+ root_domain = irq_domain_add_legacy(intc, NR_IRQS, 0, 0,
+ &xtensa_irq_domain_ops, NULL);
+ irq_set_default_host(root_domain);
variant_init_irq();
}
diff --git a/arch/xtensa/kernel/time.c b/arch/xtensa/kernel/time.c
index 19b32a0..ffb4741 100644
--- a/arch/xtensa/kernel/time.c
+++ b/arch/xtensa/kernel/time.c
@@ -22,6 +22,7 @@
#include <linux/irq.h>
#include <linux/profile.h>
#include <linux/delay.h>
+#include <linux/irqdomain.h>
#include <asm/timex.h>
#include <asm/platform.h>
@@ -52,6 +53,7 @@
void __init time_init(void)
{
+ unsigned int irq;
#ifdef CONFIG_XTENSA_CALIBRATE_CCOUNT
printk("Calibrating CPU frequency ");
platform_calibrate_ccount();
@@ -62,7 +64,8 @@
/* Initialize the linux timer interrupt. */
- setup_irq(LINUX_TIMER_INT, &timer_irqaction);
+ irq = irq_create_mapping(NULL, LINUX_TIMER_INT);
+ setup_irq(irq, &timer_irqaction);
set_linux_timer(get_ccount() + CCOUNT_PER_JIFFY);
}