[PATCH 4.9 104/108] xtensa: dont use linux IRQ #0

Greg Kroah-Hartman
2017-06-15T18:00:33Z

From: Max Filippov <jcmvbkbc@gmail.com>

commit e5c86679d5e864947a52fb31e45a425dea3e7fa9 upstream.

Linux IRQ #0 is reserved for error reporting and may not be used.
Increase NR_IRQS for one additional slot and increase
irq_domain_add_legacy parameter first_irq value to 1, so that linux
IRQ #0 is not associated with hardware IRQ #0 in legacy IRQ domains.
Introduce macro XTENSA_PIC_LINUX_IRQ for static translation of xtensa
PIC hardware IRQ # to linux IRQ #. Use this macro in XTFPGA platform
data definitions.

This fixes inability to use hardware IRQ #0 in configurations that don't
use device tree and allows for non-identity mapping between linux IRQ #
and hardware IRQ #.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/xtensa/include/asm/irq.h | 3 ++-
arch/xtensa/kernel/irq.c | 5 -----
arch/xtensa/platforms/xtfpga/include/platform/hardware.h | 6 ++++--
arch/xtensa/platforms/xtfpga/setup.c | 10 +++++-----
drivers/irqchip/irq-xtensa-mx.c | 2 +-
drivers/irqchip/irq-xtensa-pic.c | 2 +-
6 files changed, 13 insertions(+), 15 deletions(-)

--- a/arch/xtensa/include/asm/irq.h
+++ b/arch/xtensa/include/asm/irq.h
@@ -29,7 +29,8 @@ static inline void variant_irq_disable(u
# define PLATFORM_NR_IRQS 0
#endif
#define XTENSA_NR_IRQS XCHAL_NUM_INTERRUPTS
-#define NR_IRQS (XTENSA_NR_IRQS + VARIANT_NR_IRQS + PLATFORM_NR_IRQS)
+#define NR_IRQS (XTENSA_NR_IRQS + VARIANT_NR_IRQS + PLATFORM_NR_IRQS + 1)
+#define XTENSA_PIC_LINUX_IRQ(hwirq) ((hwirq) + 1)

#if VARIANT_NR_IRQS == 0
static inline void variant_init_irq(void) { }
--- a/arch/xtensa/kernel/irq.c
+++ b/arch/xtensa/kernel/irq.c
@@ -34,11 +34,6 @@ asmlinkage void do_IRQ(int hwirq, struct
{
int irq = irq_find_mapping(NULL, hwirq);

- if (hwirq >= NR_IRQS) {
- printk(KERN_EMERG "%s: cannot handle IRQ %d\n",
- __func__, hwirq);
- }
-
#ifdef CONFIG_DEBUG_STACKOVERFLOW
/* Debugging check for stack overflow: is there less than 1KB free? */
{
--- a/arch/xtensa/platforms/xtfpga/include/platform/hardware.h
+++ b/arch/xtensa/platforms/xtfpga/include/platform/hardware.h
@@ -24,16 +24,18 @@

/* Interrupt configuration. */

-#define PLATFORM_NR_IRQS 10
+#define PLATFORM_NR_IRQS 0

/* Default assignment of LX60 devices to external interrupts. */

#ifdef CONFIG_XTENSA_MX
#define DUART16552_INTNUM XCHAL_EXTINT3_NUM
#define OETH_IRQ XCHAL_EXTINT4_NUM
+#define C67X00_IRQ XCHAL_EXTINT8_NUM
#else
#define DUART16552_INTNUM XCHAL_EXTINT0_NUM
#define OETH_IRQ XCHAL_EXTINT1_NUM
+#define C67X00_IRQ XCHAL_EXTINT5_NUM
#endif

/*
@@ -63,5 +65,5 @@

#define C67X00_PADDR (XCHAL_KIO_PADDR + 0x0D0D0000)
#define C67X00_SIZE 0x10
-#define C67X00_IRQ 5
+
#endif /* __XTENSA_XTAVNET_HARDWARE_H */
--- a/arch/xtensa/platforms/xtfpga/setup.c
+++ b/arch/xtensa/platforms/xtfpga/setup.c
@@ -175,8 +175,8 @@ static struct resource ethoc_res[] = {
.flags = IORESOURCE_MEM,
},
[2] = { /* IRQ number */
- .start = OETH_IRQ,
- .end = OETH_IRQ,
+ .start = XTENSA_PIC_LINUX_IRQ(OETH_IRQ),
+ .end = XTENSA_PIC_LINUX_IRQ(OETH_IRQ),
.flags = IORESOURCE_IRQ,
},
};
@@ -213,8 +213,8 @@ static struct resource c67x00_res[] = {
.flags = IORESOURCE_MEM,
},
[1] = { /* IRQ number */
- .start = C67X00_IRQ,
- .end = C67X00_IRQ,
+ .start = XTENSA_PIC_LINUX_IRQ(C67X00_IRQ),
+ .end = XTENSA_PIC_LINUX_IRQ(C67X00_IRQ),
.flags = IORESOURCE_IRQ,
},
};
@@ -247,7 +247,7 @@ static struct resource serial_resource =
static struct plat_serial8250_port serial_platform_data[] = {
[0] = {
.mapbase = DUART16552_PADDR,
- .irq = DUART16552_INTNUM,
+ .irq = XTENSA_PIC_LINUX_IRQ(DUART16552_INTNUM),
.flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST |
UPF_IOREMAP,
.iotype = XCHAL_HAVE_BE ? UPIO_MEM32BE : UPIO_MEM32,
--- a/drivers/irqchip/irq-xtensa-mx.c
+++ b/drivers/irqchip/irq-xtensa-mx.c
@@ -142,7 +142,7 @@ static struct irq_chip xtensa_mx_irq_chi
int __init xtensa_mx_init_legacy(struct device_node *interrupt_parent)
{
struct irq_domain *root_domain =
- irq_domain_add_legacy(NULL, NR_IRQS, 0, 0,
+ irq_domain_add_legacy(NULL, NR_IRQS - 1, 1, 0,
&xtensa_mx_irq_domain_ops,
&xtensa_mx_irq_chip);
irq_set_default_host(root_domain);
--- a/drivers/irqchip/irq-xtensa-pic.c
+++ b/drivers/irqchip/irq-xtensa-pic.c
@@ -89,7 +89,7 @@ static struct irq_chip xtensa_irq_chip =
int __init xtensa_pic_init_legacy(struct device_node *interrupt_parent)
{
struct irq_domain *root_domain =
- irq_domain_add_legacy(NULL, NR_IRQS, 0, 0,
+ irq_domain_add_legacy(NULL, NR_IRQS - 1, 1, 0,
&xtensa_irq_domain_ops, &xtensa_irq_chip);
irq_set_default_host(root_domain);
return 0;