[PATCH v2] openrisc: irq: use irqchip framework
From: Stefan Kristiansson
Date: Mon May 19 2014 - 16:12:33 EST
In addition to consolidating the or1k-pic with other interrupt
controllers, this makes OpenRISC less tied to its on-cpu
interrupt controller.
All or1k-pic specific parts are moved out of irq.c and into
drivers/irqchip/irq-or1k-pic.c
In that transition, a couple of changes have been done:
- The wrongly handled or1k_pic_mask_ack() for the non-or1200
case have been fixed.
- The warnings for the non-or1200 case have been removed.
- A hook for registering a handle_arch_irq function have been
added.
Signed-off-by: Stefan Kristiansson <stefan.kristiansson@xxxxxxxxxxxxx>
---
Changes in v2:
- Move or1k-pic related code into irq-or1k-pic
- Add documentation for device tree bindings
---
.../interrupt-controller/opencores,or1k-pic.txt | 16 +++
arch/openrisc/Kconfig | 1 +
arch/openrisc/include/asm/irq.h | 3 +
arch/openrisc/kernel/irq.c | 146 ++-------------------
drivers/irqchip/Kconfig | 4 +
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-or1k-pic.c | 135 +++++++++++++++++++
7 files changed, 173 insertions(+), 133 deletions(-)
create mode 100644 Documentation/devicetree/bindings/interrupt-controller/opencores,or1k-pic.txt
create mode 100644 drivers/irqchip/irq-or1k-pic.c
diff --git a/Documentation/devicetree/bindings/interrupt-controller/opencores,or1k-pic.txt b/Documentation/devicetree/bindings/interrupt-controller/opencores,or1k-pic.txt
new file mode 100644
index 0000000..1da0b78
--- /dev/null
+++ b/Documentation/devicetree/bindings/interrupt-controller/opencores,or1k-pic.txt
@@ -0,0 +1,16 @@
+OpenRISC 1000 Programmable Interrupt Controller
+
+Required properties:
+
+- compatible : should be "opencores,o1k-pic"
+- interrupt-controller : Identifies the node as an interrupt controller
+- #interrupt-cells : Specifies the number of cells needed to encode an
+ interrupt source. The value shall be 1.
+
+Example:
+
+intc: interrupt-controller {
+ compatible = "opencores,or1k-pic";
+ interrupt-controller;
+ #interrupt-cells = <1>;
+};
diff --git a/arch/openrisc/Kconfig b/arch/openrisc/Kconfig
index 2ca7b91..8120fe2 100644
--- a/arch/openrisc/Kconfig
+++ b/arch/openrisc/Kconfig
@@ -23,6 +23,7 @@ config OPENRISC
select GENERIC_STRNLEN_USER
select MODULES_USE_ELF_RELA
select HAVE_DEBUG_STACKOVERFLOW
+ select OR1K_PIC
config MMU
def_bool y
diff --git a/arch/openrisc/include/asm/irq.h b/arch/openrisc/include/asm/irq.h
index eb612b1..b84634c 100644
--- a/arch/openrisc/include/asm/irq.h
+++ b/arch/openrisc/include/asm/irq.h
@@ -24,4 +24,7 @@
#define NO_IRQ (-1)
+void handle_IRQ(unsigned int, struct pt_regs *);
+extern void set_handle_irq(void (*handle_irq)(struct pt_regs *));
+
#endif /* __ASM_OPENRISC_IRQ_H__ */
diff --git a/arch/openrisc/kernel/irq.c b/arch/openrisc/kernel/irq.c
index 8ec77bc..967eb14 100644
--- a/arch/openrisc/kernel/irq.c
+++ b/arch/openrisc/kernel/irq.c
@@ -16,11 +16,10 @@
#include <linux/interrupt.h>
#include <linux/init.h>
-#include <linux/of.h>
#include <linux/ftrace.h>
#include <linux/irq.h>
+#include <linux/irqchip.h>
#include <linux/export.h>
-#include <linux/irqdomain.h>
#include <linux/irqflags.h>
/* read interrupt enabled status */
@@ -37,150 +36,31 @@ void arch_local_irq_restore(unsigned long flags)
}
EXPORT_SYMBOL(arch_local_irq_restore);
-
-/* OR1K PIC implementation */
-
-/* We're a couple of cycles faster than the generic implementations with
- * these 'fast' versions.
- */
-
-static void or1k_pic_mask(struct irq_data *data)
-{
- mtspr(SPR_PICMR, mfspr(SPR_PICMR) & ~(1UL << data->hwirq));
-}
-
-static void or1k_pic_unmask(struct irq_data *data)
-{
- mtspr(SPR_PICMR, mfspr(SPR_PICMR) | (1UL << data->hwirq));
-}
-
-static void or1k_pic_ack(struct irq_data *data)
-{
- /* EDGE-triggered interrupts need to be ack'ed in order to clear
- * the latch.
- * LEVEL-triggered interrupts do not need to be ack'ed; however,
- * ack'ing the interrupt has no ill-effect and is quicker than
- * trying to figure out what type it is...
- */
-
- /* The OpenRISC 1000 spec says to write a 1 to the bit to ack the
- * interrupt, but the OR1200 does this backwards and requires a 0
- * to be written...
- */
-
-#ifdef CONFIG_OR1K_1200
- /* There are two oddities with the OR1200 PIC implementation:
- * i) LEVEL-triggered interrupts are latched and need to be cleared
- * ii) the interrupt latch is cleared by writing a 0 to the bit,
- * as opposed to a 1 as mandated by the spec
- */
-
- mtspr(SPR_PICSR, mfspr(SPR_PICSR) & ~(1UL << data->hwirq));
-#else
- WARN(1, "Interrupt handling possibly broken\n");
- mtspr(SPR_PICSR, (1UL << data->hwirq));
-#endif
-}
-
-static void or1k_pic_mask_ack(struct irq_data *data)
-{
- /* Comments for pic_ack apply here, too */
-
-#ifdef CONFIG_OR1K_1200
- mtspr(SPR_PICMR, mfspr(SPR_PICMR) & ~(1UL << data->hwirq));
- mtspr(SPR_PICSR, mfspr(SPR_PICSR) & ~(1UL << data->hwirq));
-#else
- WARN(1, "Interrupt handling possibly broken\n");
- mtspr(SPR_PICMR, (1UL << data->hwirq));
- mtspr(SPR_PICSR, (1UL << data->hwirq));
-#endif
-}
-
-#if 0
-static int or1k_pic_set_type(struct irq_data *data, unsigned int flow_type)
-{
- /* There's nothing to do in the PIC configuration when changing
- * flow type. Level and edge-triggered interrupts are both
- * supported, but it's PIC-implementation specific which type
- * is handled. */
-
- return irq_setup_alt_chip(data, flow_type);
-}
-#endif
-
-static struct irq_chip or1k_dev = {
- .name = "or1k-PIC",
- .irq_unmask = or1k_pic_unmask,
- .irq_mask = or1k_pic_mask,
- .irq_ack = or1k_pic_ack,
- .irq_mask_ack = or1k_pic_mask_ack,
-};
-
-static struct irq_domain *root_domain;
-
-static inline int pic_get_irq(int first)
-{
- int hwirq;
-
- hwirq = ffs(mfspr(SPR_PICSR) >> first);
- if (!hwirq)
- return NO_IRQ;
- else
- hwirq = hwirq + first -1;
-
- return irq_find_mapping(root_domain, hwirq);
-}
-
-
-static int or1k_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw)
+void __init init_IRQ(void)
{
- irq_set_chip_and_handler_name(irq, &or1k_dev,
- handle_level_irq, "level");
- irq_set_status_flags(irq, IRQ_LEVEL | IRQ_NOPROBE);
-
- return 0;
+ irqchip_init();
}
-static const struct irq_domain_ops or1k_irq_domain_ops = {
- .xlate = irq_domain_xlate_onecell,
- .map = or1k_map,
-};
-
-/*
- * This sets up the IRQ domain for the PIC built in to the OpenRISC
- * 1000 CPU. This is the "root" domain as these are the interrupts
- * that directly trigger an exception in the CPU.
- */
-static void __init or1k_irq_init(void)
-{
- struct device_node *intc = NULL;
-
- /* The interrupt controller device node is mandatory */
- intc = of_find_compatible_node(NULL, NULL, "opencores,or1k-pic");
- BUG_ON(!intc);
-
- /* Disable all interrupts until explicitly requested */
- mtspr(SPR_PICMR, (0UL));
-
- root_domain = irq_domain_add_linear(intc, 32,
- &or1k_irq_domain_ops, NULL);
-}
+static void (*handle_arch_irq)(struct pt_regs *);
-void __init init_IRQ(void)
+void __init set_handle_irq(void (*handle_irq)(struct pt_regs *))
{
- or1k_irq_init();
+ handle_arch_irq = handle_irq;
}
-void __irq_entry do_IRQ(struct pt_regs *regs)
+void handle_IRQ(unsigned int irq, struct pt_regs *regs)
{
- int irq = -1;
struct pt_regs *old_regs = set_irq_regs(regs);
irq_enter();
- while ((irq = pic_get_irq(irq + 1)) != NO_IRQ)
- generic_handle_irq(irq);
+ generic_handle_irq(irq);
irq_exit();
set_irq_regs(old_regs);
}
+
+void __irq_entry do_IRQ(struct pt_regs *regs)
+{
+ handle_arch_irq(regs);
+}
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 3792a1a..f657872 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -61,3 +61,7 @@ config VERSATILE_FPGA_IRQ_NR
int
default 4
depends on VERSATILE_FPGA_IRQ
+
+config OR1K_PIC
+ bool
+ select IRQ_DOMAIN
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index c60b901..1ae2c103 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -22,3 +22,4 @@ obj-$(CONFIG_RENESAS_IRQC) += irq-renesas-irqc.o
obj-$(CONFIG_VERSATILE_FPGA_IRQ) += irq-versatile-fpga.o
obj-$(CONFIG_ARCH_VT8500) += irq-vt8500.o
obj-$(CONFIG_TB10X_IRQC) += irq-tb10x.o
+obj-$(CONFIG_OR1K_PIC) += irq-or1k-pic.o
diff --git a/drivers/irqchip/irq-or1k-pic.c b/drivers/irqchip/irq-or1k-pic.c
new file mode 100644
index 0000000..989c055
--- /dev/null
+++ b/drivers/irqchip/irq-or1k-pic.c
@@ -0,0 +1,135 @@
+/*
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@xxxxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/irq.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+
+#include "irqchip.h"
+
+/* OR1K PIC implementation */
+
+/* We're a couple of cycles faster than the generic implementations with
+ * these 'fast' versions.
+ */
+
+static void or1k_pic_mask(struct irq_data *data)
+{
+ mtspr(SPR_PICMR, mfspr(SPR_PICMR) & ~(1UL << data->hwirq));
+}
+
+static void or1k_pic_unmask(struct irq_data *data)
+{
+ mtspr(SPR_PICMR, mfspr(SPR_PICMR) | (1UL << data->hwirq));
+}
+
+static void or1k_pic_ack(struct irq_data *data)
+{
+ /* EDGE-triggered interrupts need to be ack'ed in order to clear
+ * the latch.
+ * LEVEL-triggered interrupts do not need to be ack'ed; however,
+ * ack'ing the interrupt has no ill-effect and is quicker than
+ * trying to figure out what type it is...
+ */
+
+ /* The OpenRISC 1000 spec says to write a 1 to the bit to ack the
+ * interrupt, but the OR1200 does this backwards and requires a 0
+ * to be written...
+ */
+
+#ifdef CONFIG_OR1K_1200
+ /* There are two oddities with the OR1200 PIC implementation:
+ * i) LEVEL-triggered interrupts are latched and need to be cleared
+ * ii) the interrupt latch is cleared by writing a 0 to the bit,
+ * as opposed to a 1 as mandated by the spec
+ */
+
+ mtspr(SPR_PICSR, mfspr(SPR_PICSR) & ~(1UL << data->hwirq));
+#else
+ mtspr(SPR_PICSR, (1UL << data->hwirq));
+#endif
+}
+
+static void or1k_pic_mask_ack(struct irq_data *data)
+{
+ mtspr(SPR_PICMR, mfspr(SPR_PICMR) & ~(1UL << data->hwirq));
+
+ /* Comments for pic_ack apply here, too */
+#ifdef CONFIG_OR1K_1200
+ mtspr(SPR_PICSR, mfspr(SPR_PICSR) & ~(1UL << data->hwirq));
+#else
+ mtspr(SPR_PICSR, (1UL << data->hwirq));
+#endif
+}
+
+static struct irq_chip or1k_dev = {
+ .name = "or1k-PIC",
+ .irq_unmask = or1k_pic_unmask,
+ .irq_mask = or1k_pic_mask,
+ .irq_ack = or1k_pic_ack,
+ .irq_mask_ack = or1k_pic_mask_ack,
+};
+
+static struct irq_domain *root_domain;
+
+static inline int pic_get_irq(int first)
+{
+ int hwirq;
+
+ hwirq = ffs(mfspr(SPR_PICSR) >> first);
+ if (!hwirq)
+ return NO_IRQ;
+ else
+ hwirq = hwirq + first -1;
+
+ return irq_find_mapping(root_domain, hwirq);
+}
+
+static void or1k_pic_handle_irq(struct pt_regs *regs)
+{
+ int irq = -1;
+
+ while ((irq = pic_get_irq(irq + 1)) != NO_IRQ)
+ handle_IRQ(irq, regs);
+}
+
+static int or1k_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw)
+{
+ irq_set_chip_and_handler_name(irq, &or1k_dev,
+ handle_level_irq, "level");
+ irq_set_status_flags(irq, IRQ_LEVEL | IRQ_NOPROBE);
+
+ return 0;
+}
+
+static const struct irq_domain_ops or1k_irq_domain_ops = {
+ .xlate = irq_domain_xlate_onecell,
+ .map = or1k_map,
+};
+
+/*
+ * This sets up the IRQ domain for the PIC built in to the OpenRISC
+ * 1000 CPU. This is the "root" domain as these are the interrupts
+ * that directly trigger an exception in the CPU.
+ */
+static int __init
+or1k_irq_init(struct device_node *intc, struct device_node *parent)
+{
+ /* Disable all interrupts until explicitly requested */
+ mtspr(SPR_PICMR, (0UL));
+
+ root_domain = irq_domain_add_linear(intc, 32,
+ &or1k_irq_domain_ops, NULL);
+
+ set_handle_irq(or1k_pic_handle_irq);
+
+ return 0;
+}
+IRQCHIP_DECLARE(or1k_pic, "opencores,or1k-pic", or1k_irq_init);
--
1.8.3.2
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