[PATCH 0/2] GIC OF bindings

[PATCH 0/2] GIC OF bindings

[Rob Herring]

From: Rob Herring <rob.herring@calxeda.com>

With recent patches for VIC device tree support and GIC MULTI_IRQ support,
it is evident that the irq domain support should be moved into the core GIC
code and not be dependent on the DT initialization. So I've split things up
into 2 patches separating irq_domain and device-tree code.

This should only change the internals of the GIC code. The binding is
unchanged from the previous version. Yeah!

The full series is available here. This includes Russell's devel-stable and
for-next branches and Nico's vmalloc branch.

git://git.jdl.com/software/linux-3.0.git gic

Rob

Rob Herring (2):
  ARM: gic: add irq_domain support
  ARM: gic: add OF based initialization

 Documentation/devicetree/bindings/arm/gic.txt |   55 ++++++++++
 arch/arm/common/Kconfig                       |    1 +
 arch/arm/common/gic.c                         |  144 +++++++++++++++++++------
 arch/arm/include/asm/hardware/gic.h           |    4 +
 4 files changed, 171 insertions(+), 33 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/arm/gic.txt

-- 
1.7.5.4

[PATCH 0/2] GIC OF bindings

[Rob Herring]

From: Rob Herring <rob.herring@calxeda.com>

With recent patches for VIC device tree support and GIC MULTI_IRQ support,
it is evident that the irq domain support should be moved into the core GIC
code and not be dependent on the DT initialization. So I've split things up
into 2 patches separating irq_domain and device-tree code.

This should only change the internals of the GIC code. The binding is
unchanged from the previous version. Yeah!

The full series is available here. This includes Russell's devel-stable and
for-next branches and Nico's vmalloc branch.

git://git.jdl.com/software/linux-3.0.git gic

Rob

Rob Herring (2):
  ARM: gic: add irq_domain support
  ARM: gic: add OF based initialization

 Documentation/devicetree/bindings/arm/gic.txt |   55 ++++++++++
 arch/arm/common/Kconfig                       |    1 +
 arch/arm/common/gic.c                         |  144 +++++++++++++++++++------
 arch/arm/include/asm/hardware/gic.h           |    4 +
 4 files changed, 171 insertions(+), 33 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/arm/gic.txt

-- 
1.7.5.4

[PATCH 1/2] ARM: gic: add irq_domain support

[Rob Herring]

From: Rob Herring <rob.herring@calxeda.com>

Convert the gic interrupt controller to use irq domains in preparation
for device-tree binding and MULTI_IRQ. This allows for translation between
GIC interrupt IDs and Linux irq numbers.

The meaning of irq_offset has changed. It now is just the number of skipped
GIC interrupt IDs for the controller. It will be 16 for primary GIC and 32
for secondary GICs.

Cc: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
---
 arch/arm/common/Kconfig             |    1 +
 arch/arm/common/gic.c               |   80 ++++++++++++++++++++--------------
 arch/arm/include/asm/hardware/gic.h |    3 +
 3 files changed, 51 insertions(+), 33 deletions(-)

diff --git a/arch/arm/common/Kconfig b/arch/arm/common/Kconfig
index 4b71766..74df9ca 100644
--- a/arch/arm/common/Kconfig
+++ b/arch/arm/common/Kconfig
@@ -1,4 +1,5 @@
 config ARM_GIC
+	select IRQ_DOMAIN
 	bool
 
 config ARM_VIC
diff --git a/arch/arm/common/gic.c b/arch/arm/common/gic.c
index 8b5be72..fa59c99 100644
--- a/arch/arm/common/gic.c
+++ b/arch/arm/common/gic.c
@@ -29,6 +29,7 @@
 #include <linux/cpu_pm.h>
 #include <linux/cpumask.h>
 #include <linux/io.h>
+#include <linux/irqdomain.h>
 
 #include <asm/irq.h>
 #include <asm/mach/irq.h>
@@ -73,7 +74,7 @@ static inline void __iomem *gic_cpu_base(struct irq_data *d)
 static inline unsigned int gic_irq(struct irq_data *d)
 {
 	struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
-	return d->irq - gic_data->irq_offset;
+	return d->hwirq + gic_data->irq_offset;
 }
 
 /*
@@ -81,7 +82,7 @@ static inline unsigned int gic_irq(struct irq_data *d)
  */
 static void gic_mask_irq(struct irq_data *d)
 {
-	u32 mask = 1 << (d->irq % 32);
+	u32 mask = 1 << (gic_irq(d) % 32);
 
 	spin_lock(&irq_controller_lock);
 	writel_relaxed(mask, gic_dist_base(d) + GIC_DIST_ENABLE_CLEAR + (gic_irq(d) / 32) * 4);
@@ -92,7 +93,7 @@ static void gic_mask_irq(struct irq_data *d)
 
 static void gic_unmask_irq(struct irq_data *d)
 {
-	u32 mask = 1 << (d->irq % 32);
+	u32 mask = 1 << (gic_irq(d) % 32);
 
 	spin_lock(&irq_controller_lock);
 	if (gic_arch_extn.irq_unmask)
@@ -173,7 +174,7 @@ static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
 			    bool force)
 {
 	void __iomem *reg = gic_dist_base(d) + GIC_DIST_TARGET + (gic_irq(d) & ~3);
-	unsigned int shift = (d->irq % 4) * 8;
+	unsigned int shift = (gic_irq(d) % 4) * 8;
 	unsigned int cpu = cpumask_any_and(mask_val, cpu_online_mask);
 	u32 val, mask, bit;
 
@@ -224,7 +225,7 @@ static void gic_handle_cascade_irq(unsigned int irq, struct irq_desc *desc)
 	if (gic_irq == 1023)
 		goto out;
 
-	cascade_irq = gic_irq + chip_data->irq_offset;
+	cascade_irq = irq_domain_to_irq(&chip_data->domain, gic_irq);
 	if (unlikely(gic_irq < 32 || gic_irq > 1020 || cascade_irq >= NR_IRQS))
 		do_bad_IRQ(cascade_irq, desc);
 	else
@@ -256,10 +257,10 @@ void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq)
 	irq_set_chained_handler(irq, gic_handle_cascade_irq);
 }
 
-static void __init gic_dist_init(struct gic_chip_data *gic,
-	unsigned int irq_start)
+static void __init gic_dist_init(struct gic_chip_data *gic)
 {
-	unsigned int gic_irqs, irq_limit, i;
+	unsigned int gic_irqs = gic->gic_irqs;
+	unsigned int i;
 	u32 cpumask;
 	void __iomem *base = gic->dist_base;
 	u32 cpu = 0;
@@ -275,17 +276,6 @@ static void __init gic_dist_init(struct gic_chip_data *gic,
 	writel_relaxed(0, base + GIC_DIST_CTRL);
 
 	/*
-	 * Find out how many interrupts are supported.
-	 * The GIC only supports up to 1020 interrupt sources.
-	 */
-	gic_irqs = readl_relaxed(base + GIC_DIST_CTR) & 0x1f;
-	gic_irqs = (gic_irqs + 1) * 32;
-	if (gic_irqs > 1020)
-		gic_irqs = 1020;
-
-	gic->gic_irqs = gic_irqs;
-
-	/*
 	 * Set all global interrupts to be level triggered, active low.
 	 */
 	for (i = 32; i < gic_irqs; i += 16)
@@ -311,19 +301,13 @@ static void __init gic_dist_init(struct gic_chip_data *gic,
 		writel_relaxed(0xffffffff, base + GIC_DIST_ENABLE_CLEAR + i * 4 / 32);
 
 	/*
-	 * Limit number of interrupts registered to the platform maximum
-	 */
-	irq_limit = gic->irq_offset + gic_irqs;
-	if (WARN_ON(irq_limit > NR_IRQS))
-		irq_limit = NR_IRQS;
-
-	/*
 	 * Setup the Linux IRQ subsystem.
 	 */
-	for (i = irq_start; i < irq_limit; i++) {
-		irq_set_chip_and_handler(i, &gic_chip, handle_fasteoi_irq);
-		irq_set_chip_data(i, gic);
-		set_irq_flags(i, IRQF_VALID | IRQF_PROBE);
+	for (i = 0; i < gic->domain.nr_irq; i++) {
+		int irq = irq_domain_to_irq(&gic->domain, i);
+		irq_set_chip_and_handler(irq, &gic_chip, handle_fasteoi_irq);
+		irq_set_chip_data(irq, gic);
+		set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
 	}
 
 	writel_relaxed(1, base + GIC_DIST_CTRL);
@@ -535,23 +519,53 @@ static void __init gic_pm_init(struct gic_chip_data *gic)
 }
 #endif
 
+const struct irq_domain_ops gic_irq_domain_ops = {
+};
+
 void __init gic_init(unsigned int gic_nr, unsigned int irq_start,
 	void __iomem *dist_base, void __iomem *cpu_base)
 {
 	struct gic_chip_data *gic;
+	struct irq_domain *domain;
+	int gic_irqs;
 
 	BUG_ON(gic_nr >= MAX_GIC_NR);
 
 	gic = &gic_data[gic_nr];
+	domain = &gic->domain;
 	gic->dist_base = dist_base;
 	gic->cpu_base = cpu_base;
-	gic->irq_offset = (irq_start - 1) & ~31;
 
-	if (gic_nr == 0)
+	/*
+	 * For primary GICs, skip over SGIs.
+	 * For secondary GICs, skip over PPIs, too.
+	 */
+	if (gic_nr == 0) {
 		gic_cpu_base_addr = cpu_base;
+		gic->irq_offset = 16;
+		irq_start = (irq_start & ~31) + 16;
+	} else
+		gic->irq_offset = 32;
+
+	/*
+	 * Find out how many interrupts are supported.
+	 * The GIC only supports up to 1020 interrupt sources.
+	 */
+	gic_irqs = readl_relaxed(dist_base + GIC_DIST_CTR) & 0x1f;
+	gic_irqs = (gic_irqs + 1) * 32;
+	if (gic_irqs > 1020)
+		gic_irqs = 1020;
+	gic->gic_irqs = gic_irqs;
+
+	domain->nr_irq = gic_irqs - gic->irq_offset;
+	domain->irq_base = irq_alloc_descs(-1, irq_start, domain->nr_irq,
+					   numa_node_id());
+	domain->priv = gic;
+	domain->ops = &gic_irq_domain_ops;
+	irq_domain_add(domain);
 
 	gic_chip.flags |= gic_arch_extn.flags;
-	gic_dist_init(gic, irq_start);
+	gic_dist_init(gic);
 	gic_cpu_init(gic);
 	gic_pm_init(gic);
 }
diff --git a/arch/arm/include/asm/hardware/gic.h b/arch/arm/include/asm/hardware/gic.h
index c562705..4893b10 100644
--- a/arch/arm/include/asm/hardware/gic.h
+++ b/arch/arm/include/asm/hardware/gic.h
@@ -33,6 +33,8 @@
 #define GIC_DIST_SOFTINT		0xf00
 
 #ifndef __ASSEMBLY__
+#include <linux/irqdomain.h>
+
 extern void __iomem *gic_cpu_base_addr;
 extern struct irq_chip gic_arch_extn;
 
@@ -53,6 +55,7 @@ struct gic_chip_data {
 	u32 __percpu *saved_ppi_enable;
 	u32 __percpu *saved_ppi_conf;
 #endif
+	struct irq_domain domain;
 	unsigned int gic_irqs;
 };
 #endif
-- 
1.7.5.4

[PATCH 1/2] ARM: gic: add irq_domain support

[Rob Herring]

From: Rob Herring <rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org>

Convert the gic interrupt controller to use irq domains in preparation
for device-tree binding and MULTI_IRQ. This allows for translation between
GIC interrupt IDs and Linux irq numbers.

The meaning of irq_offset has changed. It now is just the number of skipped
GIC interrupt IDs for the controller. It will be 16 for primary GIC and 32
for secondary GICs.

Cc: Marc Zyngier <marc.zyngier-5wv7dgnIgG8@public.gmane.org>
Signed-off-by: Rob Herring <rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org>
---
 arch/arm/common/Kconfig             |    1 +
 arch/arm/common/gic.c               |   80 ++++++++++++++++++++--------------
 arch/arm/include/asm/hardware/gic.h |    3 +
 3 files changed, 51 insertions(+), 33 deletions(-)

diff --git a/arch/arm/common/Kconfig b/arch/arm/common/Kconfig
index 4b71766..74df9ca 100644
--- a/arch/arm/common/Kconfig
+++ b/arch/arm/common/Kconfig
@@ -1,4 +1,5 @@
 config ARM_GIC
+	select IRQ_DOMAIN
 	bool
 
 config ARM_VIC
diff --git a/arch/arm/common/gic.c b/arch/arm/common/gic.c
index 8b5be72..fa59c99 100644
--- a/arch/arm/common/gic.c
+++ b/arch/arm/common/gic.c
@@ -29,6 +29,7 @@
 #include <linux/cpu_pm.h>
 #include <linux/cpumask.h>
 #include <linux/io.h>
+#include <linux/irqdomain.h>
 
 #include <asm/irq.h>
 #include <asm/mach/irq.h>
@@ -73,7 +74,7 @@ static inline void __iomem *gic_cpu_base(struct irq_data *d)
 static inline unsigned int gic_irq(struct irq_data *d)
 {
 	struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
-	return d->irq - gic_data->irq_offset;
+	return d->hwirq + gic_data->irq_offset;
 }
 
 /*
@@ -81,7 +82,7 @@ static inline unsigned int gic_irq(struct irq_data *d)
  */
 static void gic_mask_irq(struct irq_data *d)
 {
-	u32 mask = 1 << (d->irq % 32);
+	u32 mask = 1 << (gic_irq(d) % 32);
 
 	spin_lock(&irq_controller_lock);
 	writel_relaxed(mask, gic_dist_base(d) + GIC_DIST_ENABLE_CLEAR + (gic_irq(d) / 32) * 4);
@@ -92,7 +93,7 @@ static void gic_mask_irq(struct irq_data *d)
 
 static void gic_unmask_irq(struct irq_data *d)
 {
-	u32 mask = 1 << (d->irq % 32);
+	u32 mask = 1 << (gic_irq(d) % 32);
 
 	spin_lock(&irq_controller_lock);
 	if (gic_arch_extn.irq_unmask)
@@ -173,7 +174,7 @@ static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
 			    bool force)
 {
 	void __iomem *reg = gic_dist_base(d) + GIC_DIST_TARGET + (gic_irq(d) & ~3);
-	unsigned int shift = (d->irq % 4) * 8;
+	unsigned int shift = (gic_irq(d) % 4) * 8;
 	unsigned int cpu = cpumask_any_and(mask_val, cpu_online_mask);
 	u32 val, mask, bit;
 
@@ -224,7 +225,7 @@ static void gic_handle_cascade_irq(unsigned int irq, struct irq_desc *desc)
 	if (gic_irq == 1023)
 		goto out;
 
-	cascade_irq = gic_irq + chip_data->irq_offset;
+	cascade_irq = irq_domain_to_irq(&chip_data->domain, gic_irq);
 	if (unlikely(gic_irq < 32 || gic_irq > 1020 || cascade_irq >= NR_IRQS))
 		do_bad_IRQ(cascade_irq, desc);
 	else
@@ -256,10 +257,10 @@ void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq)
 	irq_set_chained_handler(irq, gic_handle_cascade_irq);
 }
 
-static void __init gic_dist_init(struct gic_chip_data *gic,
-	unsigned int irq_start)
+static void __init gic_dist_init(struct gic_chip_data *gic)
 {
-	unsigned int gic_irqs, irq_limit, i;
+	unsigned int gic_irqs = gic->gic_irqs;
+	unsigned int i;
 	u32 cpumask;
 	void __iomem *base = gic->dist_base;
 	u32 cpu = 0;
@@ -275,17 +276,6 @@ static void __init gic_dist_init(struct gic_chip_data *gic,
 	writel_relaxed(0, base + GIC_DIST_CTRL);
 
 	/*
-	 * Find out how many interrupts are supported.
-	 * The GIC only supports up to 1020 interrupt sources.
-	 */
-	gic_irqs = readl_relaxed(base + GIC_DIST_CTR) & 0x1f;
-	gic_irqs = (gic_irqs + 1) * 32;
-	if (gic_irqs > 1020)
-		gic_irqs = 1020;
-
-	gic->gic_irqs = gic_irqs;
-
-	/*
 	 * Set all global interrupts to be level triggered, active low.
 	 */
 	for (i = 32; i < gic_irqs; i += 16)
@@ -311,19 +301,13 @@ static void __init gic_dist_init(struct gic_chip_data *gic,
 		writel_relaxed(0xffffffff, base + GIC_DIST_ENABLE_CLEAR + i * 4 / 32);
 
 	/*
-	 * Limit number of interrupts registered to the platform maximum
-	 */
-	irq_limit = gic->irq_offset + gic_irqs;
-	if (WARN_ON(irq_limit > NR_IRQS))
-		irq_limit = NR_IRQS;
-
-	/*
 	 * Setup the Linux IRQ subsystem.
 	 */
-	for (i = irq_start; i < irq_limit; i++) {
-		irq_set_chip_and_handler(i, &gic_chip, handle_fasteoi_irq);
-		irq_set_chip_data(i, gic);
-		set_irq_flags(i, IRQF_VALID | IRQF_PROBE);
+	for (i = 0; i < gic->domain.nr_irq; i++) {
+		int irq = irq_domain_to_irq(&gic->domain, i);
+		irq_set_chip_and_handler(irq, &gic_chip, handle_fasteoi_irq);
+		irq_set_chip_data(irq, gic);
+		set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
 	}
 
 	writel_relaxed(1, base + GIC_DIST_CTRL);
@@ -535,23 +519,53 @@ static void __init gic_pm_init(struct gic_chip_data *gic)
 }
 #endif
 
+const struct irq_domain_ops gic_irq_domain_ops = {
+};
+
 void __init gic_init(unsigned int gic_nr, unsigned int irq_start,
 	void __iomem *dist_base, void __iomem *cpu_base)
 {
 	struct gic_chip_data *gic;
+	struct irq_domain *domain;
+	int gic_irqs;
 
 	BUG_ON(gic_nr >= MAX_GIC_NR);
 
 	gic = &gic_data[gic_nr];
+	domain = &gic->domain;
 	gic->dist_base = dist_base;
 	gic->cpu_base = cpu_base;
-	gic->irq_offset = (irq_start - 1) & ~31;
 
-	if (gic_nr == 0)
+	/*
+	 * For primary GICs, skip over SGIs.
+	 * For secondary GICs, skip over PPIs, too.
+	 */
+	if (gic_nr == 0) {
 		gic_cpu_base_addr = cpu_base;
+		gic->irq_offset = 16;
+		irq_start = (irq_start & ~31) + 16;
+	} else
+		gic->irq_offset = 32;
+
+	/*
+	 * Find out how many interrupts are supported.
+	 * The GIC only supports up to 1020 interrupt sources.
+	 */
+	gic_irqs = readl_relaxed(dist_base + GIC_DIST_CTR) & 0x1f;
+	gic_irqs = (gic_irqs + 1) * 32;
+	if (gic_irqs > 1020)
+		gic_irqs = 1020;
+	gic->gic_irqs = gic_irqs;
+
+	domain->nr_irq = gic_irqs - gic->irq_offset;
+	domain->irq_base = irq_alloc_descs(-1, irq_start, domain->nr_irq,
+					   numa_node_id());
+	domain->priv = gic;
+	domain->ops = &gic_irq_domain_ops;
+	irq_domain_add(domain);
 
 	gic_chip.flags |= gic_arch_extn.flags;
-	gic_dist_init(gic, irq_start);
+	gic_dist_init(gic);
 	gic_cpu_init(gic);
 	gic_pm_init(gic);
 }
diff --git a/arch/arm/include/asm/hardware/gic.h b/arch/arm/include/asm/hardware/gic.h
index c562705..4893b10 100644
--- a/arch/arm/include/asm/hardware/gic.h
+++ b/arch/arm/include/asm/hardware/gic.h
@@ -33,6 +33,8 @@
 #define GIC_DIST_SOFTINT		0xf00
 
 #ifndef __ASSEMBLY__
+#include <linux/irqdomain.h>
+
 extern void __iomem *gic_cpu_base_addr;
 extern struct irq_chip gic_arch_extn;
 
@@ -53,6 +55,7 @@ struct gic_chip_data {
 	u32 __percpu *saved_ppi_enable;
 	u32 __percpu *saved_ppi_conf;
 #endif
+	struct irq_domain domain;
 	unsigned int gic_irqs;
 };
 #endif
-- 
1.7.5.4

[PATCH 1/2] ARM: gic: add irq_domain support

[Rob Herring]

From: Rob Herring <rob.herring@calxeda.com>

Convert the gic interrupt controller to use irq domains in preparation
for device-tree binding and MULTI_IRQ. This allows for translation between
GIC interrupt IDs and Linux irq numbers.

The meaning of irq_offset has changed. It now is just the number of skipped
GIC interrupt IDs for the controller. It will be 16 for primary GIC and 32
for secondary GICs.

Cc: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
---
 arch/arm/common/Kconfig             |    1 +
 arch/arm/common/gic.c               |   80 ++++++++++++++++++++--------------
 arch/arm/include/asm/hardware/gic.h |    3 +
 3 files changed, 51 insertions(+), 33 deletions(-)

diff --git a/arch/arm/common/Kconfig b/arch/arm/common/Kconfig
index 4b71766..74df9ca 100644
--- a/arch/arm/common/Kconfig
+++ b/arch/arm/common/Kconfig
@@ -1,4 +1,5 @@
 config ARM_GIC
+	select IRQ_DOMAIN
 	bool
 
 config ARM_VIC
diff --git a/arch/arm/common/gic.c b/arch/arm/common/gic.c
index 8b5be72..fa59c99 100644
--- a/arch/arm/common/gic.c
+++ b/arch/arm/common/gic.c
@@ -29,6 +29,7 @@
 #include <linux/cpu_pm.h>
 #include <linux/cpumask.h>
 #include <linux/io.h>
+#include <linux/irqdomain.h>
 
 #include <asm/irq.h>
 #include <asm/mach/irq.h>
@@ -73,7 +74,7 @@ static inline void __iomem *gic_cpu_base(struct irq_data *d)
 static inline unsigned int gic_irq(struct irq_data *d)
 {
 	struct gic_chip_data *gic_data = irq_data_get_irq_chip_data(d);
-	return d->irq - gic_data->irq_offset;
+	return d->hwirq + gic_data->irq_offset;
 }
 
 /*
@@ -81,7 +82,7 @@ static inline unsigned int gic_irq(struct irq_data *d)
  */
 static void gic_mask_irq(struct irq_data *d)
 {
-	u32 mask = 1 << (d->irq % 32);
+	u32 mask = 1 << (gic_irq(d) % 32);
 
 	spin_lock(&irq_controller_lock);
 	writel_relaxed(mask, gic_dist_base(d) + GIC_DIST_ENABLE_CLEAR + (gic_irq(d) / 32) * 4);
@@ -92,7 +93,7 @@ static void gic_mask_irq(struct irq_data *d)
 
 static void gic_unmask_irq(struct irq_data *d)
 {
-	u32 mask = 1 << (d->irq % 32);
+	u32 mask = 1 << (gic_irq(d) % 32);
 
 	spin_lock(&irq_controller_lock);
 	if (gic_arch_extn.irq_unmask)
@@ -173,7 +174,7 @@ static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
 			    bool force)
 {
 	void __iomem *reg = gic_dist_base(d) + GIC_DIST_TARGET + (gic_irq(d) & ~3);
-	unsigned int shift = (d->irq % 4) * 8;
+	unsigned int shift = (gic_irq(d) % 4) * 8;
 	unsigned int cpu = cpumask_any_and(mask_val, cpu_online_mask);
 	u32 val, mask, bit;
 
@@ -224,7 +225,7 @@ static void gic_handle_cascade_irq(unsigned int irq, struct irq_desc *desc)
 	if (gic_irq == 1023)
 		goto out;
 
-	cascade_irq = gic_irq + chip_data->irq_offset;
+	cascade_irq = irq_domain_to_irq(&chip_data->domain, gic_irq);
 	if (unlikely(gic_irq < 32 || gic_irq > 1020 || cascade_irq >= NR_IRQS))
 		do_bad_IRQ(cascade_irq, desc);
 	else
@@ -256,10 +257,10 @@ void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq)
 	irq_set_chained_handler(irq, gic_handle_cascade_irq);
 }
 
-static void __init gic_dist_init(struct gic_chip_data *gic,
-	unsigned int irq_start)
+static void __init gic_dist_init(struct gic_chip_data *gic)
 {
-	unsigned int gic_irqs, irq_limit, i;
+	unsigned int gic_irqs = gic->gic_irqs;
+	unsigned int i;
 	u32 cpumask;
 	void __iomem *base = gic->dist_base;
 	u32 cpu = 0;
@@ -275,17 +276,6 @@ static void __init gic_dist_init(struct gic_chip_data *gic,
 	writel_relaxed(0, base + GIC_DIST_CTRL);
 
 	/*
-	 * Find out how many interrupts are supported.
-	 * The GIC only supports up to 1020 interrupt sources.
-	 */
-	gic_irqs = readl_relaxed(base + GIC_DIST_CTR) & 0x1f;
-	gic_irqs = (gic_irqs + 1) * 32;
-	if (gic_irqs > 1020)
-		gic_irqs = 1020;
-
-	gic->gic_irqs = gic_irqs;
-
-	/*
 	 * Set all global interrupts to be level triggered, active low.
 	 */
 	for (i = 32; i < gic_irqs; i += 16)
@@ -311,19 +301,13 @@ static void __init gic_dist_init(struct gic_chip_data *gic,
 		writel_relaxed(0xffffffff, base + GIC_DIST_ENABLE_CLEAR + i * 4 / 32);
 
 	/*
-	 * Limit number of interrupts registered to the platform maximum
-	 */
-	irq_limit = gic->irq_offset + gic_irqs;
-	if (WARN_ON(irq_limit > NR_IRQS))
-		irq_limit = NR_IRQS;
-
-	/*
 	 * Setup the Linux IRQ subsystem.
 	 */
-	for (i = irq_start; i < irq_limit; i++) {
-		irq_set_chip_and_handler(i, &gic_chip, handle_fasteoi_irq);
-		irq_set_chip_data(i, gic);
-		set_irq_flags(i, IRQF_VALID | IRQF_PROBE);
+	for (i = 0; i < gic->domain.nr_irq; i++) {
+		int irq = irq_domain_to_irq(&gic->domain, i);
+		irq_set_chip_and_handler(irq, &gic_chip, handle_fasteoi_irq);
+		irq_set_chip_data(irq, gic);
+		set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
 	}
 
 	writel_relaxed(1, base + GIC_DIST_CTRL);
@@ -535,23 +519,53 @@ static void __init gic_pm_init(struct gic_chip_data *gic)
 }
 #endif
 
+const struct irq_domain_ops gic_irq_domain_ops = {
+};
+
 void __init gic_init(unsigned int gic_nr, unsigned int irq_start,
 	void __iomem *dist_base, void __iomem *cpu_base)
 {
 	struct gic_chip_data *gic;
+	struct irq_domain *domain;
+	int gic_irqs;
 
 	BUG_ON(gic_nr >= MAX_GIC_NR);
 
 	gic = &gic_data[gic_nr];
+	domain = &gic->domain;
 	gic->dist_base = dist_base;
 	gic->cpu_base = cpu_base;
-	gic->irq_offset = (irq_start - 1) & ~31;
 
-	if (gic_nr == 0)
+	/*
+	 * For primary GICs, skip over SGIs.
+	 * For secondary GICs, skip over PPIs, too.
+	 */
+	if (gic_nr == 0) {
 		gic_cpu_base_addr = cpu_base;
+		gic->irq_offset = 16;
+		irq_start = (irq_start & ~31) + 16;
+	} else
+		gic->irq_offset = 32;
+
+	/*
+	 * Find out how many interrupts are supported.
+	 * The GIC only supports up to 1020 interrupt sources.
+	 */
+	gic_irqs = readl_relaxed(dist_base + GIC_DIST_CTR) & 0x1f;
+	gic_irqs = (gic_irqs + 1) * 32;
+	if (gic_irqs > 1020)
+		gic_irqs = 1020;
+	gic->gic_irqs = gic_irqs;
+
+	domain->nr_irq = gic_irqs - gic->irq_offset;
+	domain->irq_base = irq_alloc_descs(-1, irq_start, domain->nr_irq,
+					   numa_node_id());
+	domain->priv = gic;
+	domain->ops = &gic_irq_domain_ops;
+	irq_domain_add(domain);
 
 	gic_chip.flags |= gic_arch_extn.flags;
-	gic_dist_init(gic, irq_start);
+	gic_dist_init(gic);
 	gic_cpu_init(gic);
 	gic_pm_init(gic);
 }
diff --git a/arch/arm/include/asm/hardware/gic.h b/arch/arm/include/asm/hardware/gic.h
index c562705..4893b10 100644
--- a/arch/arm/include/asm/hardware/gic.h
+++ b/arch/arm/include/asm/hardware/gic.h
@@ -33,6 +33,8 @@
 #define GIC_DIST_SOFTINT		0xf00
 
 #ifndef __ASSEMBLY__
+#include <linux/irqdomain.h>
+
 extern void __iomem *gic_cpu_base_addr;
 extern struct irq_chip gic_arch_extn;
 
@@ -53,6 +55,7 @@ struct gic_chip_data {
 	u32 __percpu *saved_ppi_enable;
 	u32 __percpu *saved_ppi_conf;
 #endif
+	struct irq_domain domain;
 	unsigned int gic_irqs;
 };
 #endif
-- 
1.7.5.4

[PATCH 2/2] ARM: gic: add OF based initialization

[Rob Herring]

From: Rob Herring <rob.herring@calxeda.com>

This adds ARM gic interrupt controller initialization using device tree
data.

The initialization function is intended to be called by of_irq_init
function like this:

const static struct of_device_id irq_match[] = {
	{ .compatible = "arm,cortex-a9-gic", .data = gic_of_init, },
	{}
};

static void __init init_irqs(void)
{
	of_irq_init(irq_match);
}

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
---
 Documentation/devicetree/bindings/arm/gic.txt |   55 +++++++++++++++++++++
 arch/arm/common/gic.c                         |   64 +++++++++++++++++++++++++
 arch/arm/include/asm/hardware/gic.h           |    1 +
 3 files changed, 120 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/arm/gic.txt

diff --git a/Documentation/devicetree/bindings/arm/gic.txt b/Documentation/devicetree/bindings/arm/gic.txt
new file mode 100644
index 0000000..52916b4
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/gic.txt
@@ -0,0 +1,55 @@
+* ARM Generic Interrupt Controller
+
+ARM SMP cores are often associated with a GIC, providing per processor
+interrupts (PPI), shared processor interrupts (SPI) and software
+generated interrupts (SGI).
+
+Primary GIC is attached directly to the CPU and typically has PPIs and SGIs.
+Secondary GICs are cascaded into the upward interrupt controller and do not
+have PPIs or SGIs.
+
+Main node required properties:
+
+- compatible : should be one of:
+	"arm,cortex-a9-gic"
+	"arm,arm11mp-gic"
+- interrupt-controller : Identifies the node as an interrupt controller
+- #interrupt-cells : Specifies the number of cells needed to encode an
+  interrupt source.  The type shall be a <u32> and the value shall be 3.
+
+  The 1st cell is the interrupt type; 0 for SPI interrupts, 1 for PPI
+  interrupts.
+
+  The 2nd cell contains the interrupt number for the interrupt type.
+  SPI interrupts are in the range [0-987].  PPI interrupts are in the
+  range [0-15].
+
+  The 3rd cell is the flags, encoded as follows:
+	bits[3:0] trigger type and level flags.
+		1 = low-to-high edge triggered
+		2 = high-to-low edge triggered
+		4 = active high level-sensitive
+		8 = active low level-sensitive
+	bits[15:8] PPI interrupt cpu mask.  Each bit corresponds to each of
+	the 8 possible cpus attached to the GIC.  A bit set to '1' indicated
+	the interrupt is wired to that CPU.  Only valid for PPI interrupts.
+
+- reg : Specifies base physical address(s) and size of the GIC registers. The
+  first region is the GIC distributor register base and size. The 2nd region is
+  the GIC cpu interface register base and size.
+
+Optional
+- interrupts	: Interrupt source of the parent interrupt controller. Only
+  present on secondary GICs.
+
+Example:
+
+	intc: interrupt-controller@fff11000 {
+		compatible = "arm,cortex-a9-gic";
+		#interrupt-cells = <3>;
+		#address-cells = <1>;
+		interrupt-controller;
+		reg = <0xfff11000 0x1000>,
+		      <0xfff10100 0x100>;
+	};
+
diff --git a/arch/arm/common/gic.c b/arch/arm/common/gic.c
index fa59c99..505ced7 100644
--- a/arch/arm/common/gic.c
+++ b/arch/arm/common/gic.c
@@ -29,6 +29,9 @@
 #include <linux/cpu_pm.h>
 #include <linux/cpumask.h>
 #include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
 #include <linux/irqdomain.h>
 
 #include <asm/irq.h>
@@ -519,7 +522,36 @@ static void __init gic_pm_init(struct gic_chip_data *gic)
 }
 #endif
 
+#ifdef CONFIG_OF
+static int gic_irq_domain_dt_translate(struct irq_domain *d,
+				       struct device_node *controller,
+				       const u32 *intspec, unsigned int intsize,
+				       unsigned long *out_hwirq, unsigned int *out_type)
+{
+	struct gic_chip_data *gic_data = d->priv;
+
+	if (d->of_node != controller)
+		return -EINVAL;
+	if (intsize < 3)
+		return -EINVAL;
+
+	*out_hwirq = intspec[1];
+	/*
+	 * We've already skipped over SGIs, so PPIs need no translation.
+	 * For SPIs, we need to skip over 16 PPIs on primary GICs.
+	 */
+	if (!intspec[0] && (gic_data->irq_offset == 16))
+		*out_hwirq += 16;
+
+	*out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
+	return 0;
+}
+#endif
+
 const struct irq_domain_ops gic_irq_domain_ops = {
+#ifdef CONFIG_OF
+	.dt_translate = gic_irq_domain_dt_translate,
+#endif
 };
 
 void __init gic_init(unsigned int gic_nr, unsigned int irq_start,
@@ -607,3 +639,35 @@ void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
 	writel_relaxed(map << 16 | irq, gic_data[0].dist_base + GIC_DIST_SOFTINT);
 }
 #endif
+
+#ifdef CONFIG_OF
+static int gic_cnt __initdata = 0;
+
+int __init gic_of_init(struct device_node *node, struct device_node *parent)
+{
+	void __iomem *cpu_base;
+	void __iomem *dist_base;
+	int irq;
+	struct irq_domain *domain = &gic_data[gic_cnt].domain;
+
+	if (WARN_ON(!node))
+		return -ENODEV;
+
+	dist_base = of_iomap(node, 0);
+	WARN(!dist_base, "unable to map gic dist registers\n");
+
+	cpu_base = of_iomap(node, 1);
+	WARN(!cpu_base, "unable to map gic cpu registers\n");
+
+	domain->of_node = of_node_get(node);
+
+	gic_init(gic_cnt, 16, dist_base, cpu_base);
+
+	if (parent) {
+		irq = irq_of_parse_and_map(node, 0);
+		gic_cascade_irq(gic_cnt, irq);
+	}
+	gic_cnt++;
+	return 0;
+}
+#endif
diff --git a/arch/arm/include/asm/hardware/gic.h b/arch/arm/include/asm/hardware/gic.h
index 4893b10..a343c96 100644
--- a/arch/arm/include/asm/hardware/gic.h
+++ b/arch/arm/include/asm/hardware/gic.h
@@ -39,6 +39,7 @@ extern void __iomem *gic_cpu_base_addr;
 extern struct irq_chip gic_arch_extn;
 
 void gic_init(unsigned int, unsigned int, void __iomem *, void __iomem *);
+int gic_of_init(struct device_node *node, struct device_node *parent);
 void gic_secondary_init(unsigned int);
 void gic_cascade_irq(unsigned int gic_nr, unsigned int irq);
 void gic_raise_softirq(const struct cpumask *mask, unsigned int irq);
-- 
1.7.5.4

[PATCH 2/2] ARM: gic: add OF based initialization

[Rob Herring]

From: Rob Herring <rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org>

This adds ARM gic interrupt controller initialization using device tree
data.

The initialization function is intended to be called by of_irq_init
function like this:

const static struct of_device_id irq_match[] = {
	{ .compatible = "arm,cortex-a9-gic", .data = gic_of_init, },
	{}
};

static void __init init_irqs(void)
{
	of_irq_init(irq_match);
}

Signed-off-by: Rob Herring <rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org>
---
 Documentation/devicetree/bindings/arm/gic.txt |   55 +++++++++++++++++++++
 arch/arm/common/gic.c                         |   64 +++++++++++++++++++++++++
 arch/arm/include/asm/hardware/gic.h           |    1 +
 3 files changed, 120 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/arm/gic.txt

diff --git a/Documentation/devicetree/bindings/arm/gic.txt b/Documentation/devicetree/bindings/arm/gic.txt
new file mode 100644
index 0000000..52916b4
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/gic.txt
@@ -0,0 +1,55 @@
+* ARM Generic Interrupt Controller
+
+ARM SMP cores are often associated with a GIC, providing per processor
+interrupts (PPI), shared processor interrupts (SPI) and software
+generated interrupts (SGI).
+
+Primary GIC is attached directly to the CPU and typically has PPIs and SGIs.
+Secondary GICs are cascaded into the upward interrupt controller and do not
+have PPIs or SGIs.
+
+Main node required properties:
+
+- compatible : should be one of:
+	"arm,cortex-a9-gic"
+	"arm,arm11mp-gic"
+- interrupt-controller : Identifies the node as an interrupt controller
+- #interrupt-cells : Specifies the number of cells needed to encode an
+  interrupt source.  The type shall be a <u32> and the value shall be 3.
+
+  The 1st cell is the interrupt type; 0 for SPI interrupts, 1 for PPI
+  interrupts.
+
+  The 2nd cell contains the interrupt number for the interrupt type.
+  SPI interrupts are in the range [0-987].  PPI interrupts are in the
+  range [0-15].
+
+  The 3rd cell is the flags, encoded as follows:
+	bits[3:0] trigger type and level flags.
+		1 = low-to-high edge triggered
+		2 = high-to-low edge triggered
+		4 = active high level-sensitive
+		8 = active low level-sensitive
+	bits[15:8] PPI interrupt cpu mask.  Each bit corresponds to each of
+	the 8 possible cpus attached to the GIC.  A bit set to '1' indicated
+	the interrupt is wired to that CPU.  Only valid for PPI interrupts.
+
+- reg : Specifies base physical address(s) and size of the GIC registers. The
+  first region is the GIC distributor register base and size. The 2nd region is
+  the GIC cpu interface register base and size.
+
+Optional
+- interrupts	: Interrupt source of the parent interrupt controller. Only
+  present on secondary GICs.
+
+Example:
+
+	intc: interrupt-controller@fff11000 {
+		compatible = "arm,cortex-a9-gic";
+		#interrupt-cells = <3>;
+		#address-cells = <1>;
+		interrupt-controller;
+		reg = <0xfff11000 0x1000>,
+		      <0xfff10100 0x100>;
+	};
+
diff --git a/arch/arm/common/gic.c b/arch/arm/common/gic.c
index fa59c99..505ced7 100644
--- a/arch/arm/common/gic.c
+++ b/arch/arm/common/gic.c
@@ -29,6 +29,9 @@
 #include <linux/cpu_pm.h>
 #include <linux/cpumask.h>
 #include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
 #include <linux/irqdomain.h>
 
 #include <asm/irq.h>
@@ -519,7 +522,36 @@ static void __init gic_pm_init(struct gic_chip_data *gic)
 }
 #endif
 
+#ifdef CONFIG_OF
+static int gic_irq_domain_dt_translate(struct irq_domain *d,
+				       struct device_node *controller,
+				       const u32 *intspec, unsigned int intsize,
+				       unsigned long *out_hwirq, unsigned int *out_type)
+{
+	struct gic_chip_data *gic_data = d->priv;
+
+	if (d->of_node != controller)
+		return -EINVAL;
+	if (intsize < 3)
+		return -EINVAL;
+
+	*out_hwirq = intspec[1];
+	/*
+	 * We've already skipped over SGIs, so PPIs need no translation.
+	 * For SPIs, we need to skip over 16 PPIs on primary GICs.
+	 */
+	if (!intspec[0] && (gic_data->irq_offset == 16))
+		*out_hwirq += 16;
+
+	*out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
+	return 0;
+}
+#endif
+
 const struct irq_domain_ops gic_irq_domain_ops = {
+#ifdef CONFIG_OF
+	.dt_translate = gic_irq_domain_dt_translate,
+#endif
 };
 
 void __init gic_init(unsigned int gic_nr, unsigned int irq_start,
@@ -607,3 +639,35 @@ void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
 	writel_relaxed(map << 16 | irq, gic_data[0].dist_base + GIC_DIST_SOFTINT);
 }
 #endif
+
+#ifdef CONFIG_OF
+static int gic_cnt __initdata = 0;
+
+int __init gic_of_init(struct device_node *node, struct device_node *parent)
+{
+	void __iomem *cpu_base;
+	void __iomem *dist_base;
+	int irq;
+	struct irq_domain *domain = &gic_data[gic_cnt].domain;
+
+	if (WARN_ON(!node))
+		return -ENODEV;
+
+	dist_base = of_iomap(node, 0);
+	WARN(!dist_base, "unable to map gic dist registers\n");
+
+	cpu_base = of_iomap(node, 1);
+	WARN(!cpu_base, "unable to map gic cpu registers\n");
+
+	domain->of_node = of_node_get(node);
+
+	gic_init(gic_cnt, 16, dist_base, cpu_base);
+
+	if (parent) {
+		irq = irq_of_parse_and_map(node, 0);
+		gic_cascade_irq(gic_cnt, irq);
+	}
+	gic_cnt++;
+	return 0;
+}
+#endif
diff --git a/arch/arm/include/asm/hardware/gic.h b/arch/arm/include/asm/hardware/gic.h
index 4893b10..a343c96 100644
--- a/arch/arm/include/asm/hardware/gic.h
+++ b/arch/arm/include/asm/hardware/gic.h
@@ -39,6 +39,7 @@ extern void __iomem *gic_cpu_base_addr;
 extern struct irq_chip gic_arch_extn;
 
 void gic_init(unsigned int, unsigned int, void __iomem *, void __iomem *);
+int gic_of_init(struct device_node *node, struct device_node *parent);
 void gic_secondary_init(unsigned int);
 void gic_cascade_irq(unsigned int gic_nr, unsigned int irq);
 void gic_raise_softirq(const struct cpumask *mask, unsigned int irq);
-- 
1.7.5.4

[PATCH 2/2] ARM: gic: add OF based initialization

[Rob Herring]

From: Rob Herring <rob.herring@calxeda.com>

This adds ARM gic interrupt controller initialization using device tree
data.

The initialization function is intended to be called by of_irq_init
function like this:

const static struct of_device_id irq_match[] = {
	{ .compatible = "arm,cortex-a9-gic", .data = gic_of_init, },
	{}
};

static void __init init_irqs(void)
{
	of_irq_init(irq_match);
}

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
---
 Documentation/devicetree/bindings/arm/gic.txt |   55 +++++++++++++++++++++
 arch/arm/common/gic.c                         |   64 +++++++++++++++++++++++++
 arch/arm/include/asm/hardware/gic.h           |    1 +
 3 files changed, 120 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/arm/gic.txt

diff --git a/Documentation/devicetree/bindings/arm/gic.txt b/Documentation/devicetree/bindings/arm/gic.txt
new file mode 100644
index 0000000..52916b4
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/gic.txt
@@ -0,0 +1,55 @@
+* ARM Generic Interrupt Controller
+
+ARM SMP cores are often associated with a GIC, providing per processor
+interrupts (PPI), shared processor interrupts (SPI) and software
+generated interrupts (SGI).
+
+Primary GIC is attached directly to the CPU and typically has PPIs and SGIs.
+Secondary GICs are cascaded into the upward interrupt controller and do not
+have PPIs or SGIs.
+
+Main node required properties:
+
+- compatible : should be one of:
+	"arm,cortex-a9-gic"
+	"arm,arm11mp-gic"
+- interrupt-controller : Identifies the node as an interrupt controller
+- #interrupt-cells : Specifies the number of cells needed to encode an
+  interrupt source.  The type shall be a <u32> and the value shall be 3.
+
+  The 1st cell is the interrupt type; 0 for SPI interrupts, 1 for PPI
+  interrupts.
+
+  The 2nd cell contains the interrupt number for the interrupt type.
+  SPI interrupts are in the range [0-987].  PPI interrupts are in the
+  range [0-15].
+
+  The 3rd cell is the flags, encoded as follows:
+	bits[3:0] trigger type and level flags.
+		1 = low-to-high edge triggered
+		2 = high-to-low edge triggered
+		4 = active high level-sensitive
+		8 = active low level-sensitive
+	bits[15:8] PPI interrupt cpu mask.  Each bit corresponds to each of
+	the 8 possible cpus attached to the GIC.  A bit set to '1' indicated
+	the interrupt is wired to that CPU.  Only valid for PPI interrupts.
+
+- reg : Specifies base physical address(s) and size of the GIC registers. The
+  first region is the GIC distributor register base and size. The 2nd region is
+  the GIC cpu interface register base and size.
+
+Optional
+- interrupts	: Interrupt source of the parent interrupt controller. Only
+  present on secondary GICs.
+
+Example:
+
+	intc: interrupt-controller at fff11000 {
+		compatible = "arm,cortex-a9-gic";
+		#interrupt-cells = <3>;
+		#address-cells = <1>;
+		interrupt-controller;
+		reg = <0xfff11000 0x1000>,
+		      <0xfff10100 0x100>;
+	};
+
diff --git a/arch/arm/common/gic.c b/arch/arm/common/gic.c
index fa59c99..505ced7 100644
--- a/arch/arm/common/gic.c
+++ b/arch/arm/common/gic.c
@@ -29,6 +29,9 @@
 #include <linux/cpu_pm.h>
 #include <linux/cpumask.h>
 #include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
 #include <linux/irqdomain.h>
 
 #include <asm/irq.h>
@@ -519,7 +522,36 @@ static void __init gic_pm_init(struct gic_chip_data *gic)
 }
 #endif
 
+#ifdef CONFIG_OF
+static int gic_irq_domain_dt_translate(struct irq_domain *d,
+				       struct device_node *controller,
+				       const u32 *intspec, unsigned int intsize,
+				       unsigned long *out_hwirq, unsigned int *out_type)
+{
+	struct gic_chip_data *gic_data = d->priv;
+
+	if (d->of_node != controller)
+		return -EINVAL;
+	if (intsize < 3)
+		return -EINVAL;
+
+	*out_hwirq = intspec[1];
+	/*
+	 * We've already skipped over SGIs, so PPIs need no translation.
+	 * For SPIs, we need to skip over 16 PPIs on primary GICs.
+	 */
+	if (!intspec[0] && (gic_data->irq_offset == 16))
+		*out_hwirq += 16;
+
+	*out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
+	return 0;
+}
+#endif
+
 const struct irq_domain_ops gic_irq_domain_ops = {
+#ifdef CONFIG_OF
+	.dt_translate = gic_irq_domain_dt_translate,
+#endif
 };
 
 void __init gic_init(unsigned int gic_nr, unsigned int irq_start,
@@ -607,3 +639,35 @@ void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
 	writel_relaxed(map << 16 | irq, gic_data[0].dist_base + GIC_DIST_SOFTINT);
 }
 #endif
+
+#ifdef CONFIG_OF
+static int gic_cnt __initdata = 0;
+
+int __init gic_of_init(struct device_node *node, struct device_node *parent)
+{
+	void __iomem *cpu_base;
+	void __iomem *dist_base;
+	int irq;
+	struct irq_domain *domain = &gic_data[gic_cnt].domain;
+
+	if (WARN_ON(!node))
+		return -ENODEV;
+
+	dist_base = of_iomap(node, 0);
+	WARN(!dist_base, "unable to map gic dist registers\n");
+
+	cpu_base = of_iomap(node, 1);
+	WARN(!cpu_base, "unable to map gic cpu registers\n");
+
+	domain->of_node = of_node_get(node);
+
+	gic_init(gic_cnt, 16, dist_base, cpu_base);
+
+	if (parent) {
+		irq = irq_of_parse_and_map(node, 0);
+		gic_cascade_irq(gic_cnt, irq);
+	}
+	gic_cnt++;
+	return 0;
+}
+#endif
diff --git a/arch/arm/include/asm/hardware/gic.h b/arch/arm/include/asm/hardware/gic.h
index 4893b10..a343c96 100644
--- a/arch/arm/include/asm/hardware/gic.h
+++ b/arch/arm/include/asm/hardware/gic.h
@@ -39,6 +39,7 @@ extern void __iomem *gic_cpu_base_addr;
 extern struct irq_chip gic_arch_extn;
 
 void gic_init(unsigned int, unsigned int, void __iomem *, void __iomem *);
+int gic_of_init(struct device_node *node, struct device_node *parent);
 void gic_secondary_init(unsigned int);
 void gic_cascade_irq(unsigned int gic_nr, unsigned int irq);
 void gic_raise_softirq(const struct cpumask *mask, unsigned int irq);
-- 
1.7.5.4

Re: [PATCH 0/2] GIC OF bindings

[Jamie Iles]

On Wed, Sep 28, 2011 at 10:53:54PM -0500, Rob Herring wrote:
> From: Rob Herring <rob.herring@calxeda.com>
> 
> With recent patches for VIC device tree support and GIC MULTI_IRQ support,
> it is evident that the irq domain support should be moved into the core GIC
> code and not be dependent on the DT initialization. So I've split things up
> into 2 patches separating irq_domain and device-tree code.
> 
> This should only change the internals of the GIC code. The binding is
> unchanged from the previous version. Yeah!
> 
> The full series is available here. This includes Russell's devel-stable and
> for-next branches and Nico's vmalloc branch.

Looks good to me!

Reviewed-by: Jamie Iles <jamie@jamieiles.com>

[PATCH 0/2] GIC OF bindings

[Jamie Iles]

On Wed, Sep 28, 2011 at 10:53:54PM -0500, Rob Herring wrote:
> From: Rob Herring <rob.herring@calxeda.com>
> 
> With recent patches for VIC device tree support and GIC MULTI_IRQ support,
> it is evident that the irq domain support should be moved into the core GIC
> code and not be dependent on the DT initialization. So I've split things up
> into 2 patches separating irq_domain and device-tree code.
> 
> This should only change the internals of the GIC code. The binding is
> unchanged from the previous version. Yeah!
> 
> The full series is available here. This includes Russell's devel-stable and
> for-next branches and Nico's vmalloc branch.

Looks good to me!

Reviewed-by: Jamie Iles <jamie@jamieiles.com>

Re: [PATCH 1/2] ARM: gic: add irq_domain support

[Grant Likely]

On Wed, Sep 28, 2011 at 10:53:55PM -0500, Rob Herring wrote:
> From: Rob Herring <rob.herring@calxeda.com>
> 
> Convert the gic interrupt controller to use irq domains in preparation
> for device-tree binding and MULTI_IRQ. This allows for translation between
> GIC interrupt IDs and Linux irq numbers.
> 
> The meaning of irq_offset has changed. It now is just the number of skipped
> GIC interrupt IDs for the controller. It will be 16 for primary GIC and 32
> for secondary GICs.

[...]

>  /*
> @@ -81,7 +82,7 @@ static inline unsigned int gic_irq(struct irq_data *d)
>   */
>  static void gic_mask_irq(struct irq_data *d)
>  {
> -	u32 mask = 1 << (d->irq % 32);
> +	u32 mask = 1 << (gic_irq(d) % 32);

This can probably change simply to d->hwirq if irq_offset is
eliminated as I describe below.

>  void __init gic_init(unsigned int gic_nr, unsigned int irq_start,
>  	void __iomem *dist_base, void __iomem *cpu_base)
>  {
>  	struct gic_chip_data *gic;
> +	struct irq_domain *domain;
> +	int gic_irqs;
>  
>  	BUG_ON(gic_nr >= MAX_GIC_NR);
>  
>  	gic = &gic_data[gic_nr];
> +	domain = &gic->domain;
>  	gic->dist_base = dist_base;
>  	gic->cpu_base = cpu_base;
> -	gic->irq_offset = (irq_start - 1) & ~31;
>  
> -	if (gic_nr == 0)
> +	/*
> +	 * For primary GICs, skip over SGIs.
> +	 * For secondary GICs, skip over PPIs, too.
> +	 */
> +	if (gic_nr == 0) {
>  		gic_cpu_base_addr = cpu_base;
> +		gic->irq_offset = 16;
> +		irq_start = (irq_start & ~31) + 16;

With the switch to irq_domain, there should no longer be any need for
a ~31 mask on the irq_start number.  Yes, you'll want to make sure
that it doesn't allocate below irq 16, but the driver should
completely use the irq_domain to manage the mapping from linux-irq
number to hwirq number.  The ~31 mask appears to have been an
optimization to quickly calculate hwirq number from the linux one, but
that value is now found in irq_data->hwirq.

irq_offset could almost be dropped entirely outside of probe because
it no longer matters.  Instead, populate the to_irq() hook so that the
hwirq value gets set correctly from the outset.

It would be better in general to have a consistent view of what the
hwirq number means regardless of if it is a root GIC.

g.

Re: [PATCH 1/2] ARM: gic: add irq_domain support

[Grant Likely]

On Wed, Sep 28, 2011 at 10:53:55PM -0500, Rob Herring wrote:
> From: Rob Herring <rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org>
> 
> Convert the gic interrupt controller to use irq domains in preparation
> for device-tree binding and MULTI_IRQ. This allows for translation between
> GIC interrupt IDs and Linux irq numbers.
> 
> The meaning of irq_offset has changed. It now is just the number of skipped
> GIC interrupt IDs for the controller. It will be 16 for primary GIC and 32
> for secondary GICs.

[...]

>  /*
> @@ -81,7 +82,7 @@ static inline unsigned int gic_irq(struct irq_data *d)
>   */
>  static void gic_mask_irq(struct irq_data *d)
>  {
> -	u32 mask = 1 << (d->irq % 32);
> +	u32 mask = 1 << (gic_irq(d) % 32);

This can probably change simply to d->hwirq if irq_offset is
eliminated as I describe below.

>  void __init gic_init(unsigned int gic_nr, unsigned int irq_start,
>  	void __iomem *dist_base, void __iomem *cpu_base)
>  {
>  	struct gic_chip_data *gic;
> +	struct irq_domain *domain;
> +	int gic_irqs;
>  
>  	BUG_ON(gic_nr >= MAX_GIC_NR);
>  
>  	gic = &gic_data[gic_nr];
> +	domain = &gic->domain;
>  	gic->dist_base = dist_base;
>  	gic->cpu_base = cpu_base;
> -	gic->irq_offset = (irq_start - 1) & ~31;
>  
> -	if (gic_nr == 0)
> +	/*
> +	 * For primary GICs, skip over SGIs.
> +	 * For secondary GICs, skip over PPIs, too.
> +	 */
> +	if (gic_nr == 0) {
>  		gic_cpu_base_addr = cpu_base;
> +		gic->irq_offset = 16;
> +		irq_start = (irq_start & ~31) + 16;

With the switch to irq_domain, there should no longer be any need for
a ~31 mask on the irq_start number.  Yes, you'll want to make sure
that it doesn't allocate below irq 16, but the driver should
completely use the irq_domain to manage the mapping from linux-irq
number to hwirq number.  The ~31 mask appears to have been an
optimization to quickly calculate hwirq number from the linux one, but
that value is now found in irq_data->hwirq.

irq_offset could almost be dropped entirely outside of probe because
it no longer matters.  Instead, populate the to_irq() hook so that the
hwirq value gets set correctly from the outset.

It would be better in general to have a consistent view of what the
hwirq number means regardless of if it is a root GIC.

g.

[PATCH 1/2] ARM: gic: add irq_domain support

[Grant Likely]

On Wed, Sep 28, 2011 at 10:53:55PM -0500, Rob Herring wrote:
> From: Rob Herring <rob.herring@calxeda.com>
> 
> Convert the gic interrupt controller to use irq domains in preparation
> for device-tree binding and MULTI_IRQ. This allows for translation between
> GIC interrupt IDs and Linux irq numbers.
> 
> The meaning of irq_offset has changed. It now is just the number of skipped
> GIC interrupt IDs for the controller. It will be 16 for primary GIC and 32
> for secondary GICs.

[...]

>  /*
> @@ -81,7 +82,7 @@ static inline unsigned int gic_irq(struct irq_data *d)
>   */
>  static void gic_mask_irq(struct irq_data *d)
>  {
> -	u32 mask = 1 << (d->irq % 32);
> +	u32 mask = 1 << (gic_irq(d) % 32);

This can probably change simply to d->hwirq if irq_offset is
eliminated as I describe below.

>  void __init gic_init(unsigned int gic_nr, unsigned int irq_start,
>  	void __iomem *dist_base, void __iomem *cpu_base)
>  {
>  	struct gic_chip_data *gic;
> +	struct irq_domain *domain;
> +	int gic_irqs;
>  
>  	BUG_ON(gic_nr >= MAX_GIC_NR);
>  
>  	gic = &gic_data[gic_nr];
> +	domain = &gic->domain;
>  	gic->dist_base = dist_base;
>  	gic->cpu_base = cpu_base;
> -	gic->irq_offset = (irq_start - 1) & ~31;
>  
> -	if (gic_nr == 0)
> +	/*
> +	 * For primary GICs, skip over SGIs.
> +	 * For secondary GICs, skip over PPIs, too.
> +	 */
> +	if (gic_nr == 0) {
>  		gic_cpu_base_addr = cpu_base;
> +		gic->irq_offset = 16;
> +		irq_start = (irq_start & ~31) + 16;

With the switch to irq_domain, there should no longer be any need for
a ~31 mask on the irq_start number.  Yes, you'll want to make sure
that it doesn't allocate below irq 16, but the driver should
completely use the irq_domain to manage the mapping from linux-irq
number to hwirq number.  The ~31 mask appears to have been an
optimization to quickly calculate hwirq number from the linux one, but
that value is now found in irq_data->hwirq.

irq_offset could almost be dropped entirely outside of probe because
it no longer matters.  Instead, populate the to_irq() hook so that the
hwirq value gets set correctly from the outset.

It would be better in general to have a consistent view of what the
hwirq number means regardless of if it is a root GIC.

g.

Re: [PATCH 2/2] ARM: gic: add OF based initialization

[Grant Likely]

On Wed, Sep 28, 2011 at 10:53:56PM -0500, Rob Herring wrote:
> From: Rob Herring <rob.herring@calxeda.com>
> 
> This adds ARM gic interrupt controller initialization using device tree
> data.
> 
> The initialization function is intended to be called by of_irq_init
> function like this:
> 
> const static struct of_device_id irq_match[] = {
> 	{ .compatible = "arm,cortex-a9-gic", .data = gic_of_init, },
> 	{}
> };
> 
> static void __init init_irqs(void)
> {
> 	of_irq_init(irq_match);
> }
> 
> Signed-off-by: Rob Herring <rob.herring@calxeda.com>

Looks good.

g.

[PATCH 2/2] ARM: gic: add OF based initialization

[Grant Likely]

On Wed, Sep 28, 2011 at 10:53:56PM -0500, Rob Herring wrote:
> From: Rob Herring <rob.herring@calxeda.com>
> 
> This adds ARM gic interrupt controller initialization using device tree
> data.
> 
> The initialization function is intended to be called by of_irq_init
> function like this:
> 
> const static struct of_device_id irq_match[] = {
> 	{ .compatible = "arm,cortex-a9-gic", .data = gic_of_init, },
> 	{}
> };
> 
> static void __init init_irqs(void)
> {
> 	of_irq_init(irq_match);
> }
> 
> Signed-off-by: Rob Herring <rob.herring@calxeda.com>

Looks good.

g.

Re: [PATCH 1/2] ARM: gic: add irq_domain support

[Rob Herring]

On 09/29/2011 12:15 PM, Grant Likely wrote:
> On Wed, Sep 28, 2011 at 10:53:55PM -0500, Rob Herring wrote:
>> From: Rob Herring <rob.herring@calxeda.com>
>>
>> Convert the gic interrupt controller to use irq domains in preparation
>> for device-tree binding and MULTI_IRQ. This allows for translation between
>> GIC interrupt IDs and Linux irq numbers.
>>
>> The meaning of irq_offset has changed. It now is just the number of skipped
>> GIC interrupt IDs for the controller. It will be 16 for primary GIC and 32
>> for secondary GICs.
> 
> [...]
> 
>>  /*
>> @@ -81,7 +82,7 @@ static inline unsigned int gic_irq(struct irq_data *d)
>>   */
>>  static void gic_mask_irq(struct irq_data *d)
>>  {
>> -	u32 mask = 1 << (d->irq % 32);
>> +	u32 mask = 1 << (gic_irq(d) % 32);
> 
> This can probably change simply to d->hwirq if irq_offset is
> eliminated as I describe below.
> 
>>  void __init gic_init(unsigned int gic_nr, unsigned int irq_start,
>>  	void __iomem *dist_base, void __iomem *cpu_base)
>>  {
>>  	struct gic_chip_data *gic;
>> +	struct irq_domain *domain;
>> +	int gic_irqs;
>>  
>>  	BUG_ON(gic_nr >= MAX_GIC_NR);
>>  
>>  	gic = &gic_data[gic_nr];
>> +	domain = &gic->domain;
>>  	gic->dist_base = dist_base;
>>  	gic->cpu_base = cpu_base;
>> -	gic->irq_offset = (irq_start - 1) & ~31;
>>  
>> -	if (gic_nr == 0)
>> +	/*
>> +	 * For primary GICs, skip over SGIs.
>> +	 * For secondary GICs, skip over PPIs, too.
>> +	 */
>> +	if (gic_nr == 0) {
>>  		gic_cpu_base_addr = cpu_base;
>> +		gic->irq_offset = 16;
>> +		irq_start = (irq_start & ~31) + 16;
> 
> With the switch to irq_domain, there should no longer be any need for
> a ~31 mask on the irq_start number.  Yes, you'll want to make sure
> that it doesn't allocate below irq 16, but the driver should
> completely use the irq_domain to manage the mapping from linux-irq
> number to hwirq number.  The ~31 mask appears to have been an
> optimization to quickly calculate hwirq number from the linux one, but
> that value is now found in irq_data->hwirq.

I started out exactly this way removing irq_offset. The problem is the
core irq domain code assumes that hwirq starts at 0, but for the gic it
starts at 16 or 32.

It could be fixed in the domain core, but that would effectively mean
moving irq_offset into the core.

The masking here is mainly to not break exynos. Everyone else passes in
a value of 16-31 which I could just hardcode to 16. So when exynos gets
all the interrupts converted over to domains, this can be removed. I
looked at it briefly and it doesn't look trivial.

> 
> irq_offset could almost be dropped entirely outside of probe because
> it no longer matters.  Instead, populate the to_irq() hook so that the
> hwirq value gets set correctly from the outset.
> 
> It would be better in general to have a consistent view of what the
> hwirq number means regardless of if it is a root GIC.

Agreed.

Rob

Re: [PATCH 1/2] ARM: gic: add irq_domain support

[Rob Herring]

On 09/29/2011 12:15 PM, Grant Likely wrote:
> On Wed, Sep 28, 2011 at 10:53:55PM -0500, Rob Herring wrote:
>> From: Rob Herring <rob.herring@calxeda.com>
>>
>> Convert the gic interrupt controller to use irq domains in preparation
>> for device-tree binding and MULTI_IRQ. This allows for translation between
>> GIC interrupt IDs and Linux irq numbers.
>>
>> The meaning of irq_offset has changed. It now is just the number of skipped
>> GIC interrupt IDs for the controller. It will be 16 for primary GIC and 32
>> for secondary GICs.
> 
> [...]
> 
>>  /*
>> @@ -81,7 +82,7 @@ static inline unsigned int gic_irq(struct irq_data *d)
>>   */
>>  static void gic_mask_irq(struct irq_data *d)
>>  {
>> -	u32 mask = 1 << (d->irq % 32);
>> +	u32 mask = 1 << (gic_irq(d) % 32);
> 
> This can probably change simply to d->hwirq if irq_offset is
> eliminated as I describe below.
> 
>>  void __init gic_init(unsigned int gic_nr, unsigned int irq_start,
>>  	void __iomem *dist_base, void __iomem *cpu_base)
>>  {
>>  	struct gic_chip_data *gic;
>> +	struct irq_domain *domain;
>> +	int gic_irqs;
>>  
>>  	BUG_ON(gic_nr >= MAX_GIC_NR);
>>  
>>  	gic = &gic_data[gic_nr];
>> +	domain = &gic->domain;
>>  	gic->dist_base = dist_base;
>>  	gic->cpu_base = cpu_base;
>> -	gic->irq_offset = (irq_start - 1) & ~31;
>>  
>> -	if (gic_nr == 0)
>> +	/*
>> +	 * For primary GICs, skip over SGIs.
>> +	 * For secondary GICs, skip over PPIs, too.
>> +	 */
>> +	if (gic_nr == 0) {
>>  		gic_cpu_base_addr = cpu_base;
>> +		gic->irq_offset = 16;
>> +		irq_start = (irq_start & ~31) + 16;
> 
> With the switch to irq_domain, there should no longer be any need for
> a ~31 mask on the irq_start number.  Yes, you'll want to make sure
> that it doesn't allocate below irq 16, but the driver should
> completely use the irq_domain to manage the mapping from linux-irq
> number to hwirq number.  The ~31 mask appears to have been an
> optimization to quickly calculate hwirq number from the linux one, but
> that value is now found in irq_data->hwirq.

I started out exactly this way removing irq_offset. The problem is the
core irq domain code assumes that hwirq starts at 0, but for the gic it
starts at 16 or 32.

It could be fixed in the domain core, but that would effectively mean
moving irq_offset into the core.

The masking here is mainly to not break exynos. Everyone else passes in
a value of 16-31 which I could just hardcode to 16. So when exynos gets
all the interrupts converted over to domains, this can be removed. I
looked at it briefly and it doesn't look trivial.

> 
> irq_offset could almost be dropped entirely outside of probe because
> it no longer matters.  Instead, populate the to_irq() hook so that the
> hwirq value gets set correctly from the outset.
> 
> It would be better in general to have a consistent view of what the
> hwirq number means regardless of if it is a root GIC.

Agreed.

Rob

[PATCH 1/2] ARM: gic: add irq_domain support

[Rob Herring]

On 09/29/2011 12:15 PM, Grant Likely wrote:
> On Wed, Sep 28, 2011 at 10:53:55PM -0500, Rob Herring wrote:
>> From: Rob Herring <rob.herring@calxeda.com>
>>
>> Convert the gic interrupt controller to use irq domains in preparation
>> for device-tree binding and MULTI_IRQ. This allows for translation between
>> GIC interrupt IDs and Linux irq numbers.
>>
>> The meaning of irq_offset has changed. It now is just the number of skipped
>> GIC interrupt IDs for the controller. It will be 16 for primary GIC and 32
>> for secondary GICs.
> 
> [...]
> 
>>  /*
>> @@ -81,7 +82,7 @@ static inline unsigned int gic_irq(struct irq_data *d)
>>   */
>>  static void gic_mask_irq(struct irq_data *d)
>>  {
>> -	u32 mask = 1 << (d->irq % 32);
>> +	u32 mask = 1 << (gic_irq(d) % 32);
> 
> This can probably change simply to d->hwirq if irq_offset is
> eliminated as I describe below.
> 
>>  void __init gic_init(unsigned int gic_nr, unsigned int irq_start,
>>  	void __iomem *dist_base, void __iomem *cpu_base)
>>  {
>>  	struct gic_chip_data *gic;
>> +	struct irq_domain *domain;
>> +	int gic_irqs;
>>  
>>  	BUG_ON(gic_nr >= MAX_GIC_NR);
>>  
>>  	gic = &gic_data[gic_nr];
>> +	domain = &gic->domain;
>>  	gic->dist_base = dist_base;
>>  	gic->cpu_base = cpu_base;
>> -	gic->irq_offset = (irq_start - 1) & ~31;
>>  
>> -	if (gic_nr == 0)
>> +	/*
>> +	 * For primary GICs, skip over SGIs.
>> +	 * For secondary GICs, skip over PPIs, too.
>> +	 */
>> +	if (gic_nr == 0) {
>>  		gic_cpu_base_addr = cpu_base;
>> +		gic->irq_offset = 16;
>> +		irq_start = (irq_start & ~31) + 16;
> 
> With the switch to irq_domain, there should no longer be any need for
> a ~31 mask on the irq_start number.  Yes, you'll want to make sure
> that it doesn't allocate below irq 16, but the driver should
> completely use the irq_domain to manage the mapping from linux-irq
> number to hwirq number.  The ~31 mask appears to have been an
> optimization to quickly calculate hwirq number from the linux one, but
> that value is now found in irq_data->hwirq.

I started out exactly this way removing irq_offset. The problem is the
core irq domain code assumes that hwirq starts at 0, but for the gic it
starts at 16 or 32.

It could be fixed in the domain core, but that would effectively mean
moving irq_offset into the core.

The masking here is mainly to not break exynos. Everyone else passes in
a value of 16-31 which I could just hardcode to 16. So when exynos gets
all the interrupts converted over to domains, this can be removed. I
looked at it briefly and it doesn't look trivial.

> 
> irq_offset could almost be dropped entirely outside of probe because
> it no longer matters.  Instead, populate the to_irq() hook so that the
> hwirq value gets set correctly from the outset.
> 
> It would be better in general to have a consistent view of what the
> hwirq number means regardless of if it is a root GIC.

Agreed.

Rob

Re: [PATCH 1/2] ARM: gic: add irq_domain support

[Grant Likely]

On Thu, Sep 29, 2011 at 04:02:44PM -0500, Rob Herring wrote:
> On 09/29/2011 12:15 PM, Grant Likely wrote:
> > On Wed, Sep 28, 2011 at 10:53:55PM -0500, Rob Herring wrote:
> >> From: Rob Herring <rob.herring@calxeda.com>
> >>
> >> Convert the gic interrupt controller to use irq domains in preparation
> >> for device-tree binding and MULTI_IRQ. This allows for translation between
> >> GIC interrupt IDs and Linux irq numbers.
> >>
> >> The meaning of irq_offset has changed. It now is just the number of skipped
> >> GIC interrupt IDs for the controller. It will be 16 for primary GIC and 32
> >> for secondary GICs.
> > 
> > [...]
> > 
> >>  /*
> >> @@ -81,7 +82,7 @@ static inline unsigned int gic_irq(struct irq_data *d)
> >>   */
> >>  static void gic_mask_irq(struct irq_data *d)
> >>  {
> >> -	u32 mask = 1 << (d->irq % 32);
> >> +	u32 mask = 1 << (gic_irq(d) % 32);
> > 
> > This can probably change simply to d->hwirq if irq_offset is
> > eliminated as I describe below.
> > 
> >>  void __init gic_init(unsigned int gic_nr, unsigned int irq_start,
> >>  	void __iomem *dist_base, void __iomem *cpu_base)
> >>  {
> >>  	struct gic_chip_data *gic;
> >> +	struct irq_domain *domain;
> >> +	int gic_irqs;
> >>  
> >>  	BUG_ON(gic_nr >= MAX_GIC_NR);
> >>  
> >>  	gic = &gic_data[gic_nr];
> >> +	domain = &gic->domain;
> >>  	gic->dist_base = dist_base;
> >>  	gic->cpu_base = cpu_base;
> >> -	gic->irq_offset = (irq_start - 1) & ~31;
> >>  
> >> -	if (gic_nr == 0)
> >> +	/*
> >> +	 * For primary GICs, skip over SGIs.
> >> +	 * For secondary GICs, skip over PPIs, too.
> >> +	 */
> >> +	if (gic_nr == 0) {
> >>  		gic_cpu_base_addr = cpu_base;
> >> +		gic->irq_offset = 16;
> >> +		irq_start = (irq_start & ~31) + 16;
> > 
> > With the switch to irq_domain, there should no longer be any need for
> > a ~31 mask on the irq_start number.  Yes, you'll want to make sure
> > that it doesn't allocate below irq 16, but the driver should
> > completely use the irq_domain to manage the mapping from linux-irq
> > number to hwirq number.  The ~31 mask appears to have been an
> > optimization to quickly calculate hwirq number from the linux one, but
> > that value is now found in irq_data->hwirq.
> 
> I started out exactly this way removing irq_offset. The problem is the
> core irq domain code assumes that hwirq starts at 0, but for the gic it
> starts at 16 or 32.
> 
> It could be fixed in the domain core, but that would effectively mean
> moving irq_offset into the core.

Fix irq_domain.  If it cannot handle this trivial case, then it won't
be able to handle the complex powerpc use cases.

g.

[PATCH 1/2] ARM: gic: add irq_domain support

[Grant Likely]

On Thu, Sep 29, 2011 at 04:02:44PM -0500, Rob Herring wrote:
> On 09/29/2011 12:15 PM, Grant Likely wrote:
> > On Wed, Sep 28, 2011 at 10:53:55PM -0500, Rob Herring wrote:
> >> From: Rob Herring <rob.herring@calxeda.com>
> >>
> >> Convert the gic interrupt controller to use irq domains in preparation
> >> for device-tree binding and MULTI_IRQ. This allows for translation between
> >> GIC interrupt IDs and Linux irq numbers.
> >>
> >> The meaning of irq_offset has changed. It now is just the number of skipped
> >> GIC interrupt IDs for the controller. It will be 16 for primary GIC and 32
> >> for secondary GICs.
> > 
> > [...]
> > 
> >>  /*
> >> @@ -81,7 +82,7 @@ static inline unsigned int gic_irq(struct irq_data *d)
> >>   */
> >>  static void gic_mask_irq(struct irq_data *d)
> >>  {
> >> -	u32 mask = 1 << (d->irq % 32);
> >> +	u32 mask = 1 << (gic_irq(d) % 32);
> > 
> > This can probably change simply to d->hwirq if irq_offset is
> > eliminated as I describe below.
> > 
> >>  void __init gic_init(unsigned int gic_nr, unsigned int irq_start,
> >>  	void __iomem *dist_base, void __iomem *cpu_base)
> >>  {
> >>  	struct gic_chip_data *gic;
> >> +	struct irq_domain *domain;
> >> +	int gic_irqs;
> >>  
> >>  	BUG_ON(gic_nr >= MAX_GIC_NR);
> >>  
> >>  	gic = &gic_data[gic_nr];
> >> +	domain = &gic->domain;
> >>  	gic->dist_base = dist_base;
> >>  	gic->cpu_base = cpu_base;
> >> -	gic->irq_offset = (irq_start - 1) & ~31;
> >>  
> >> -	if (gic_nr == 0)
> >> +	/*
> >> +	 * For primary GICs, skip over SGIs.
> >> +	 * For secondary GICs, skip over PPIs, too.
> >> +	 */
> >> +	if (gic_nr == 0) {
> >>  		gic_cpu_base_addr = cpu_base;
> >> +		gic->irq_offset = 16;
> >> +		irq_start = (irq_start & ~31) + 16;
> > 
> > With the switch to irq_domain, there should no longer be any need for
> > a ~31 mask on the irq_start number.  Yes, you'll want to make sure
> > that it doesn't allocate below irq 16, but the driver should
> > completely use the irq_domain to manage the mapping from linux-irq
> > number to hwirq number.  The ~31 mask appears to have been an
> > optimization to quickly calculate hwirq number from the linux one, but
> > that value is now found in irq_data->hwirq.
> 
> I started out exactly this way removing irq_offset. The problem is the
> core irq domain code assumes that hwirq starts at 0, but for the gic it
> starts at 16 or 32.
> 
> It could be fixed in the domain core, but that would effectively mean
> moving irq_offset into the core.

Fix irq_domain.  If it cannot handle this trivial case, then it won't
be able to handle the complex powerpc use cases.

g.