diff mbox

[v2,02/19] arm64: initial support for GICv3

Message ID 1395316386-12617-3-git-send-email-marc.zyngier@arm.com
State New
Headers show

Commit Message

Marc Zyngier March 20, 2014, 11:52 a.m. UTC
The Generic Interrupt Controller (version 3) offers services that are
similar to GICv2, with a number of additional features:
- Affinity routing based on the CPU MPIDR (ARE)
- System register for the CPU interfaces (SRE)
- Support for more that 8 CPUs
- Locality-specific Peripheral Interrupts (LPIs)
- Interrupt Translation Services (ITS)

This patch adds preliminary support for GICv3 with ARE and SRE,
non-secure mode only. It relies on higher exception levels to grant ARE
and SRE access.

Support for LPI and ITS will be added at a later time.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
 arch/arm64/Kconfig                 |   1 +
 arch/arm64/kernel/head.S           |  18 +
 arch/arm64/kernel/hyp-stub.S       |   1 +
 drivers/irqchip/Kconfig            |   5 +
 drivers/irqchip/Makefile           |   1 +
 drivers/irqchip/irq-gic-v3.c       | 650 +++++++++++++++++++++++++++++++++++++
 include/linux/irqchip/arm-gic-v3.h | 188 +++++++++++
 7 files changed, 864 insertions(+)
 create mode 100644 drivers/irqchip/irq-gic-v3.c
 create mode 100644 include/linux/irqchip/arm-gic-v3.h

Comments

Marc Zyngier March 24, 2014, 11:10 a.m. UTC | #1
Hi Zi,

On 22/03/14 01:21, Zi Shen Lim wrote:
> Hi Marc,
> 
> On Thu, Mar 20, 2014 at 4:52 AM, Marc Zyngier <marc.zyngier@arm.com
> <mailto:marc.zyngier@arm.com>> wrote:
> <snip>
>  
> 
>     +       /*
>     +        * Find out how many interrupts are supported.
>     +        * The GIC only supports up to 1020 interrupt sources
>     (SGI+PPI+SPI)
>     +        */
>     +       gic_irqs = readl_relaxed(gic_data.dist_base + GICD_TYPER) &
>     0x1f;
>     +       gic_irqs = (gic_irqs + 1) * 32;
>     +       if (gic_irqs > 1020)
>     +               gic_irqs = 1020;
>     +       gic_data.irq_nr = gic_irqs;
>     +
>     +       gic_data.domain = irq_domain_add_linear(node, gic_irqs - 16,
>     +                                               &gic_irq_domain_ops,
>     &gic_data);
> 
> 
> Why gic_irqs - 16?

Because we keep the SGIs (all 16 of them) for the core kernel (drivers
are not allowed to request them).

> 
>     __irq_domain_add(of_node, size, size, 0, ops, host_data);
> 
>         domain->hwirq_max = hwirq_max;
> 
> 
> So hwirq_max is effectively set to actual_hwirq_max-16.
> 
> Later, the following warning can be triggered:
> 
>     int irq_domain_associate(struct irq_domain *domain, unsigned int virq,
>                              irq_hw_number_t hwirq)
>     {
>             struct irq_data *irq_data = irq_get_irq_data(virq);
>             int ret;
> 
>             if (WARN(hwirq >= domain->hwirq_max,
>                      "error: hwirq 0x%x is too large for %s\n",
>     (int)hwirq, domain->name))
>                     return -EINVAL;

Do you actually see this warning being triggered? I don't. We're using a
linear domain that doesn't call into this function.

What am I missing?

Cheers,

	M.
Sudeep Holla March 24, 2014, 7:03 p.m. UTC | #2
Hi Marc,

On 20/03/14 11:52, Marc Zyngier wrote:
> The Generic Interrupt Controller (version 3) offers services that are
> similar to GICv2, with a number of additional features:
> - Affinity routing based on the CPU MPIDR (ARE)
> - System register for the CPU interfaces (SRE)
> - Support for more that 8 CPUs
> - Locality-specific Peripheral Interrupts (LPIs)
> - Interrupt Translation Services (ITS)
> 
> This patch adds preliminary support for GICv3 with ARE and SRE,
> non-secure mode only. It relies on higher exception levels to grant ARE
> and SRE access.
> 
> Support for LPI and ITS will be added at a later time.
> 
> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

[...]

> +#ifdef CONFIG_SMP
> +static int __init gic_secondary_init(struct notifier_block *nfb,
> +                                    unsigned long action, void *hcpu)
> +{
> +       if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
> +               gic_cpu_init();
> +       return NOTIFY_OK;
> +}
> +
> +/*
> + * Notifier for enabling the GIC CPU interface. Set an arbitrarily high
> + * priority because the GIC needs to be up before the ARM generic timers.
> + */
> +static struct notifier_block __initdata gic_cpu_notifier = {
> +       .notifier_call = gic_secondary_init,
> +       .priority = 100,
> +};
> +

You need to remove __init annotations in gic_populate_rdist, gic_cpu_init,
and gic_secondary_init for CPU hotplug to work.

Regards,
Sudeep
Marc Zyngier March 24, 2014, 7:07 p.m. UTC | #3
Hi Sudeep,

On 24/03/14 19:03, Sudeep Holla wrote:
> Hi Marc,
> 
> On 20/03/14 11:52, Marc Zyngier wrote:
>> The Generic Interrupt Controller (version 3) offers services that are
>> similar to GICv2, with a number of additional features:
>> - Affinity routing based on the CPU MPIDR (ARE)
>> - System register for the CPU interfaces (SRE)
>> - Support for more that 8 CPUs
>> - Locality-specific Peripheral Interrupts (LPIs)
>> - Interrupt Translation Services (ITS)
>>
>> This patch adds preliminary support for GICv3 with ARE and SRE,
>> non-secure mode only. It relies on higher exception levels to grant ARE
>> and SRE access.
>>
>> Support for LPI and ITS will be added at a later time.
>>
>> Acked-by: Catalin Marinas <catalin.marinas@arm.com>
>> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
> 
> [...]
> 
>> +#ifdef CONFIG_SMP
>> +static int __init gic_secondary_init(struct notifier_block *nfb,
>> +                                    unsigned long action, void *hcpu)
>> +{
>> +       if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
>> +               gic_cpu_init();
>> +       return NOTIFY_OK;
>> +}
>> +
>> +/*
>> + * Notifier for enabling the GIC CPU interface. Set an arbitrarily high
>> + * priority because the GIC needs to be up before the ARM generic timers.
>> + */
>> +static struct notifier_block __initdata gic_cpu_notifier = {
>> +       .notifier_call = gic_secondary_init,
>> +       .priority = 100,
>> +};
>> +
> 
> You need to remove __init annotations in gic_populate_rdist, gic_cpu_init,
> and gic_secondary_init for CPU hotplug to work.

Ah, who needs hotplug? ;-)

Very good point, thanks for noticing that. I'll fix it in the next revision!

Cheers,

	M.
Marc Zyngier March 25, 2014, 7:33 a.m. UTC | #4
On 25/03/14 06:35, Z Lim wrote:
> Hi Marc,
> 
> On Mon, Mar 24, 2014 at 4:10 AM, Marc Zyngier <marc.zyngier@arm.com
> <mailto:marc.zyngier@arm.com>> wrote:
>>
>> Hi Zi,
>>
>> On 22/03/14 01:21, Zi Shen Lim wrote:
>> > Hi Marc,
>> >
>> > On Thu, Mar 20, 2014 at 4:52 AM, Marc Zyngier <marc.zyngier@arm.com
> <mailto:marc.zyngier@arm.com>
>> > <mailto:marc.zyngier@arm.com <mailto:marc.zyngier@arm.com>>> wrote:
>> > <snip>
>> >
>> >
>> >     +       /*
>> >     +        * Find out how many interrupts are supported.
>> >     +        * The GIC only supports up to 1020 interrupt sources
>> >     (SGI+PPI+SPI)
>> >     +        */
>> >     +       gic_irqs = readl_relaxed(gic_data.dist_base + GICD_TYPER) &
>> >     0x1f;
>> >     +       gic_irqs = (gic_irqs + 1) * 32;
>> >     +       if (gic_irqs > 1020)
>> >     +               gic_irqs = 1020;
>> >     +       gic_data.irq_nr = gic_irqs;
>> >     +
>> >     +       gic_data.domain = irq_domain_add_linear(node, gic_irqs - 16,
>> >     +                                               &gic_irq_domain_ops,
>> >     &gic_data);
>> >
>> >
>> > Why gic_irqs - 16?
>>
>> Because we keep the SGIs (all 16 of them) for the core kernel (drivers
>> are not allowed to request them).
>>
>> >
>> >     __irq_domain_add(of_node, size, size, 0, ops, host_data);
>> >
>> >         domain->hwirq_max = hwirq_max;
>> >
>> >
>> > So hwirq_max is effectively set to actual_hwirq_max-16.
>> >
>> > Later, the following warning can be triggered:
>> >
>> >     int irq_domain_associate(struct irq_domain *domain, unsigned int
> virq,
>> >                              irq_hw_number_t hwirq)
>> >     {
>> >             struct irq_data *irq_data = irq_get_irq_data(virq);
>> >             int ret;
>> >
>> >             if (WARN(hwirq >= domain->hwirq_max,
>> >                      "error: hwirq 0x%x is too large for %s\n",
>> >     (int)hwirq, domain->name))
>> >                     return -EINVAL;
>>
>> Do you actually see this warning being triggered? I don't. We're using a
>> linear domain that doesn't call into this function.
> 
> I see this warning :(
> You can trigger it when a device's INT# falls within [gic_irqs-16,
> gic_irqs), which lines up with the -16 above.

Ah, got you. Hmmm. I may have to be slightly more creative then.

Thanks a lot for the report, I'll fix that as quickly as possible.

Cheers,

	M.
diff mbox

Patch

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 27bbcfc..5bd0dfe 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -9,6 +9,7 @@  config ARM64
 	select ARM_AMBA
 	select ARM_ARCH_TIMER
 	select ARM_GIC
+	select ARM_GIC_V3
 	select BUILDTIME_EXTABLE_SORT
 	select CLONE_BACKWARDS
 	select COMMON_CLK
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index 0b281ff..7c56e93 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -22,6 +22,7 @@ 
 
 #include <linux/linkage.h>
 #include <linux/init.h>
+#include <linux/irqchip/arm-gic-v3.h>
 
 #include <asm/assembler.h>
 #include <asm/ptrace.h>
@@ -183,6 +184,23 @@  CPU_LE(	bic	x0, x0, #(3 << 24)	)	// Clear the EE and E0E bits for EL1
 	msr	cnthctl_el2, x0
 	msr	cntvoff_el2, xzr		// Clear virtual offset
 
+#ifdef CONFIG_ARM_GIC_V3
+	/* GICv3 system register access */
+	mrs	x0, id_aa64pfr0_el1
+	ubfx	x0, x0, #24, #4
+	cmp	x0, #1
+	b.ne	3f
+
+	mrs	x0, ICC_SRE_EL2
+	orr	x0, x0, #1			// Set ICC_SRE_EL2.SRE==1
+	orr	x0, x0, #(1 << 3)		// Set ICC_SRE_EL2.Enable==1
+	msr	ICC_SRE_EL2, x0
+	isb					// Make sure SRE is now 1
+	msr	ICH_HCR_EL2, xzr		// Reset ICC_HCR_EL2 to defaults
+
+3:
+#endif
+
 	/* Populate ID registers. */
 	mrs	x0, midr_el1
 	mrs	x1, mpidr_el1
diff --git a/arch/arm64/kernel/hyp-stub.S b/arch/arm64/kernel/hyp-stub.S
index 0959611..a272f33 100644
--- a/arch/arm64/kernel/hyp-stub.S
+++ b/arch/arm64/kernel/hyp-stub.S
@@ -19,6 +19,7 @@ 
 
 #include <linux/init.h>
 #include <linux/linkage.h>
+#include <linux/irqchip/arm-gic-v3.h>
 
 #include <asm/assembler.h>
 #include <asm/ptrace.h>
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 61ffdca..5b55c46 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -10,6 +10,11 @@  config ARM_GIC
 config GIC_NON_BANKED
 	bool
 
+config ARM_GIC_V3
+	bool
+	select IRQ_DOMAIN
+	select MULTI_IRQ_HANDLER
+
 config ARM_NVIC
 	bool
 	select IRQ_DOMAIN
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 22e616c..4adfda8 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -14,6 +14,7 @@  obj-$(CONFIG_ORION_IRQCHIP)		+= irq-orion.o
 obj-$(CONFIG_ARCH_SUNXI)		+= irq-sun4i.o
 obj-$(CONFIG_ARCH_SPEAR3XX)		+= spear-shirq.o
 obj-$(CONFIG_ARM_GIC)			+= irq-gic.o irq-gic-common.o
+obj-$(CONFIG_ARM_GIC_V3)		+= irq-gic-v3.o irq-gic-common.o
 obj-$(CONFIG_ARM_NVIC)			+= irq-nvic.o
 obj-$(CONFIG_ARM_VIC)			+= irq-vic.o
 obj-$(CONFIG_IMGPDC_IRQ)		+= irq-imgpdc.o
diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
new file mode 100644
index 0000000..eb77a60
--- /dev/null
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -0,0 +1,650 @@ 
+/*
+ * Copyright (C) 2013, 2014 ARM Limited, All Rights Reserved.
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/cpu.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/percpu.h>
+#include <linux/slab.h>
+
+#include <linux/irqchip/arm-gic-v3.h>
+
+#include <asm/cputype.h>
+#include <asm/exception.h>
+#include <asm/smp_plat.h>
+
+#include "irq-gic-common.h"
+#include "irqchip.h"
+
+struct gic_chip_data {
+	void __iomem		*dist_base;
+	void __iomem		**redist_base;
+	void __percpu __iomem	**rdist;
+	struct irq_domain	*domain;
+	u64			redist_stride;
+	u32			redist_regions;
+	unsigned int		irq_nr;
+};
+
+static struct gic_chip_data gic_data __read_mostly;
+
+#define gic_data_rdist()		(this_cpu_ptr(gic_data.rdist.rdist))
+#define gic_data_rdist_rd_base()	(gic_data_rdist()->rd_base)
+#define gic_data_rdist_sgi_base()	(gic_data_rdist_rd_base() + SZ_64K)
+
+#define DEFAULT_PMR_VALUE	0xf0
+
+static inline unsigned int gic_irq(struct irq_data *d)
+{
+	return d->hwirq;
+}
+
+static inline int gic_irq_in_rdist(struct irq_data *d)
+{
+	return gic_irq(d) < 32;
+}
+
+static inline void __iomem *gic_dist_base(struct irq_data *d)
+{
+	if (gic_irq_in_rdist(d))	/* SGI+PPI -> SGI_base for this CPU */
+		return gic_data_rdist_sgi_base();
+
+	if (d->hwirq <= 1023)		/* SPI -> dist_base */
+		return gic_data.dist_base;
+
+	if (d->hwirq >= 8192)
+		BUG();		/* LPI Detected!!! */
+
+	return NULL;
+}
+
+static void gic_do_wait_for_rwp(void __iomem *base)
+{
+	u32 count = 1000000;	/* 1s! */
+
+	while (readl_relaxed(base + GICD_CTLR) & GICD_CTLR_RWP) {
+		count--;
+		if (!count) {
+			pr_err_ratelimited("RWP timeout, gone fishing\n");
+			return;
+		}
+		cpu_relax();
+		udelay(1);
+	};
+}
+
+/* Wait for completion of a distributor change */
+static void gic_dist_wait_for_rwp(void)
+{
+	gic_do_wait_for_rwp(gic_data.dist_base);
+}
+
+/* Wait for completion of a redistributor change */
+static void gic_redist_wait_for_rwp(void)
+{
+	gic_do_wait_for_rwp(gic_data_rdist_rd_base());
+}
+
+/* Low level accessors */
+static u64 gic_read_iar(void)
+{
+	u64 irqstat;
+
+	asm volatile("mrs %0, " __stringify(ICC_IAR1_EL1) : "=r" (irqstat));
+	return irqstat;
+}
+
+static void gic_write_pmr(u64 val)
+{
+	asm volatile("msr " __stringify(ICC_PMR_EL1) ", %0" : : "r" (val));
+}
+
+static void gic_write_ctlr(u64 val)
+{
+	asm volatile("msr " __stringify(ICC_CTLR_EL1) ", %0" : : "r" (val));
+	isb();
+}
+
+static void gic_write_grpen1(u64 val)
+{
+	asm volatile("msr " __stringify(ICC_GRPEN1_EL1) ", %0" : : "r" (val));
+	isb();
+}
+
+static void gic_write_sgi1r(u64 val)
+{
+	asm volatile("msr " __stringify(ICC_SGI1R_EL1) ", %0" : : "r" (val));
+}
+
+static void gic_enable_sre(void)
+{
+	u64 val;
+
+	asm volatile("mrs %0, " __stringify(ICC_SRE_EL1) : "=r" (val));
+	val |= GICC_SRE_EL1_SRE;
+	asm volatile("msr " __stringify(ICC_SRE_EL1) ", %0" : : "r" (val));
+	isb();
+
+	/*
+	 * Need to check that the SRE bit has actually been set. If
+	 * not, it means that SRE is disabled at EL2. We're going to
+	 * die painfully, and there is nothing we can do about it.
+	 *
+	 * Kindly inform the luser.
+	 */
+	asm volatile("mrs %0, " __stringify(ICC_SRE_EL1) : "=r" (val));
+	if (!(val & GICC_SRE_EL1_SRE))
+		pr_err("GIC: unable to set SRE (disabled at EL2), panic ahead\n");
+}
+
+static void gic_enable_redist(void)
+{
+	void __iomem *rbase;
+	u32 count = 1000000;	/* 1s! */
+	u32 val;
+
+	rbase = gic_data_rdist_rd_base();
+
+	/* Wake up this CPU redistributor */
+	val = readl_relaxed(rbase + GICR_WAKER);
+	val &= ~GICR_WAKER_ProcessorSleep;
+	writel_relaxed(val, rbase + GICR_WAKER);
+
+	while (readl_relaxed(rbase + GICR_WAKER) & GICR_WAKER_ChildrenAsleep) {
+		count--;
+		if (!count) {
+			pr_err_ratelimited("redist didn't wake up...\n");
+			return;
+		}
+		cpu_relax();
+		udelay(1);
+	};
+}
+
+/*
+ * Routines to acknowledge, disable and enable interrupts
+ */
+static void gic_poke_irq(struct irq_data *d, u32 offset)
+{
+	u32 mask = 1 << (gic_irq(d) % 32);
+	void (*rwp_wait)(void);
+	void __iomem *base;
+
+	if (gic_irq_in_rdist(d)) {
+		base = gic_data_rdist_sgi_base();
+		rwp_wait = gic_redist_wait_for_rwp;
+	} else {
+		base = gic_data.dist_base;
+		rwp_wait = gic_dist_wait_for_rwp;
+	}
+
+	writel_relaxed(mask, base + offset + (gic_irq(d) / 32) * 4);
+	rwp_wait();
+}
+
+static int gic_peek_irq(struct irq_data *d, u32 offset)
+{
+	u32 mask = 1 << (gic_irq(d) % 32);
+	void __iomem *base;
+
+	if (gic_irq_in_rdist(d))
+		base = gic_data_rdist_sgi_base();
+	else
+		base = gic_data.dist_base;
+
+	return !!(readl_relaxed(base + offset + (gic_irq(d) / 32) * 4) & mask);
+}
+
+static void gic_mask_irq(struct irq_data *d)
+{
+	gic_poke_irq(d, GICD_ICENABLER);
+}
+
+static void gic_unmask_irq(struct irq_data *d)
+{
+	gic_poke_irq(d, GICD_ISENABLER);
+}
+
+static void gic_eoi_irq(struct irq_data *d)
+{
+	gic_write_eoir(gic_irq(d));
+}
+
+static int gic_set_type(struct irq_data *d, unsigned int type)
+{
+	unsigned int irq = gic_irq(d);
+	void (*rwp_wait)(void);
+	void __iomem *base;
+
+	if (gic_irq_in_rdist(d)) {
+		base = gic_data_rdist_sgi_base();
+		rwp_wait = gic_redist_wait_for_rwp;
+	} else {
+		base = gic_data.dist_base;
+		rwp_wait = gic_dist_wait_for_rwp;
+	}
+
+	/* Interrupt configuration for SGIs can't be changed */
+	if (irq < 16)
+		return -EINVAL;
+
+	if (type != IRQ_TYPE_LEVEL_HIGH && type != IRQ_TYPE_EDGE_RISING)
+		return -EINVAL;
+
+	gic_configure_irq(irq, type, base, rwp_wait);
+
+	return 0;
+}
+
+static u64 gic_mpidr_to_affinity(u64 mpidr)
+{
+	u64 aff;
+
+	aff = (MPIDR_AFFINITY_LEVEL(mpidr, 3) << 32 |
+	       MPIDR_AFFINITY_LEVEL(mpidr, 2) << 16 |
+	       MPIDR_AFFINITY_LEVEL(mpidr, 1) << 8  |
+	       MPIDR_AFFINITY_LEVEL(mpidr, 0)) & ~GICD_IROUTER_SPI_MODE_ANY;
+
+	return aff;
+}
+
+static asmlinkage void __exception_irq_entry gic_handle_irq(struct pt_regs *regs)
+{
+	u64 irqnr;
+
+	do {
+		irqnr = gic_read_iar();
+
+		if (likely(irqnr > 15 && irqnr < 1021)) {
+			irqnr = irq_find_mapping(gic_data.domain, irqnr);
+			handle_IRQ(irqnr, regs);
+			continue;
+		}
+		if (irqnr < 16) {
+			gic_write_eoir(irqnr);
+#ifdef CONFIG_SMP
+			handle_IPI(irqnr, regs);
+#else
+			WARN_ONCE(true, "Unexpected SGI received!\n");
+#endif
+			continue;
+		}
+	} while (irqnr != 0x3ff);
+}
+
+static void __init gic_dist_init(void)
+{
+	unsigned int i;
+	u64 affinity;
+	void __iomem *base = gic_data.dist_base;
+
+	/* Disable the distributor */
+	writel_relaxed(0, base + GICD_CTLR);
+
+	gic_dist_config(base, gic_data.irq_nr, gic_dist_wait_for_rwp);
+
+	/* Enable distributor with ARE, Group1 */
+	writel_relaxed(GICD_CTLR_ARE_NS | GICD_CTLR_ENABLE_G1A | GICD_CTLR_ENABLE_G1,
+		       base + GICD_CTLR);
+
+	/*
+	 * Set all global interrupts to the boot CPU only. ARE must be
+	 * enabled.
+	 */
+	affinity = gic_mpidr_to_affinity(cpu_logical_map(smp_processor_id()));
+	for (i = 32; i < gic_data.irq_nr; i++)
+		writeq_relaxed(affinity, base + GICD_IROUTER + i * 8);
+}
+
+static int __init gic_populate_rdist(void)
+{
+	u64 mpidr = cpu_logical_map(smp_processor_id());
+	u64 typer;
+	u32 aff;
+	int i;
+
+	/* Convery affinity to a 32bit value... */
+	aff = (MPIDR_AFFINITY_LEVEL(mpidr, 3) << 24 |
+	       MPIDR_AFFINITY_LEVEL(mpidr, 2) << 16 |
+	       MPIDR_AFFINITY_LEVEL(mpidr, 1) << 8 |
+	       MPIDR_AFFINITY_LEVEL(mpidr, 0));
+
+	for (i = 0; i < gic_data.redist_regions; i++) {
+		void __iomem *ptr = gic_data.redist_base[i];
+		u32 reg;
+
+		reg = readl_relaxed(ptr + GICR_PIDR2) & GIC_PIDR2_ARCH_MASK;
+		if (reg != 0x30 && reg != 0x40) { /* We're in trouble... */
+			pr_warn("No redistributor present @%p\n", ptr);
+			break;
+		}
+
+		do {
+			typer = readq_relaxed(ptr + GICR_TYPER);
+			if ((typer >> 32) == aff) {
+				gic_data_rdist_rd_base() = ptr;
+				pr_info("CPU%d: found redistributor %llx @%p\n",
+					smp_processor_id(),
+					(unsigned long long)mpidr, ptr);
+				return 0;
+			}
+
+			if (gic_data.redist_stride) {
+				ptr += gic_data.redist_stride;
+			} else {
+				ptr += SZ_64K * 2; /* Skip RD_base + SGI_base */
+				if (typer & GICR_TYPER_VLPIS)
+					ptr += SZ_64K * 2; /* Skip VLPI_base + reserved page */
+			}
+		} while (!(typer & GICR_TYPER_LAST));
+	}
+
+	/* We couldn't even deal with ourselves... */
+	WARN(true, "CPU%d: mpidr %llx has no re-distributor!\n",
+	     smp_processor_id(), (unsigned long long)mpidr);
+	return -ENODEV;
+}
+
+static void __init gic_cpu_init(void)
+{
+	void __iomem *rbase;
+
+	/* Register ourselves with the rest of the world */
+	if (gic_populate_rdist())
+		return;
+
+	gic_enable_redist();
+
+	rbase = gic_data_rdist_sgi_base();
+
+	gic_cpu_config(rbase, gic_redist_wait_for_rwp);
+
+	/* Enable system registers */
+	gic_enable_sre();
+
+	/* Set priority mask register */
+	gic_write_pmr(DEFAULT_PMR_VALUE);
+
+	/* EOI deactivates interrupt too (mode 0) */
+	gic_write_ctlr(GICC_CTLR_EL1_EOImode_drop_dir);
+
+	/* ... and let's hit the road... */
+	gic_write_grpen1(1);
+}
+
+#ifdef CONFIG_SMP
+static int __init gic_secondary_init(struct notifier_block *nfb,
+				     unsigned long action, void *hcpu)
+{
+	if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
+		gic_cpu_init();
+	return NOTIFY_OK;
+}
+
+/*
+ * Notifier for enabling the GIC CPU interface. Set an arbitrarily high
+ * priority because the GIC needs to be up before the ARM generic timers.
+ */
+static struct notifier_block __initdata gic_cpu_notifier = {
+	.notifier_call = gic_secondary_init,
+	.priority = 100,
+};
+
+static u16 gic_compute_target_list(int *base_cpu, const struct cpumask *mask,
+				   u64 cluster_id)
+{
+	int cpu = *base_cpu;
+	u64 mpidr = cpu_logical_map(cpu);
+	u16 tlist = 0;
+
+	while (cpu < nr_cpu_ids) {
+		/*
+		 * If we ever get a cluster of more than 16 CPUs, just
+		 * scream and skip that CPU.
+		 */
+		if (WARN_ON((mpidr & 0xff) >= 16))
+			goto out;
+
+		tlist |= 1 << (mpidr & 0xf);
+
+		cpu = cpumask_next(cpu, mask);
+		if (cpu == nr_cpu_ids)
+			goto out;
+
+		mpidr = cpu_logical_map(cpu);
+
+		if (cluster_id != (mpidr & ~0xffUL)) {
+			cpu--;
+			goto out;
+		}
+	}
+out:
+	*base_cpu = cpu;
+	return tlist;
+}
+
+static void gic_send_sgi(u64 cluster_id, u16 tlist, unsigned int irq)
+{
+	u64 val;
+
+	val = (MPIDR_AFFINITY_LEVEL(cluster_id, 3) << 48	|
+	       MPIDR_AFFINITY_LEVEL(cluster_id, 2) << 32	|
+	       irq << 24			    		|
+	       MPIDR_AFFINITY_LEVEL(cluster_id, 1) << 16	|
+	       tlist);
+
+	pr_debug("CPU%d: ICC_SGI1R_EL1 %llx\n", smp_processor_id(), val);
+	gic_write_sgi1r(val);
+}
+
+static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
+{
+	int cpu;
+
+	if (WARN_ON(irq >= 16))
+		return;
+
+	/*
+	 * Ensure that stores to Normal memory are visible to the
+	 * other CPUs before issuing the IPI.
+	 */
+	smp_wmb();
+
+	for_each_cpu_mask(cpu, *mask) {
+		u64 cluster_id = cpu_logical_map(cpu) & ~0xffUL;
+		u16 tlist;
+
+		tlist = gic_compute_target_list(&cpu, mask, cluster_id);
+		gic_send_sgi(cluster_id, tlist, irq);
+	}
+
+	/* Force the above writes to ICC_SGI1R_EL1 to be executed */
+	isb();
+}
+
+static void gic_smp_init(void)
+{
+	set_smp_cross_call(gic_raise_softirq);
+	register_cpu_notifier(&gic_cpu_notifier);
+}
+
+static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
+			    bool force)
+{
+	unsigned int cpu = cpumask_any_and(mask_val, cpu_online_mask);
+	void __iomem *reg;
+	int enabled;
+	u64 val;
+
+	if (gic_irq_in_rdist(d))
+		return -EINVAL;
+
+	/* If interrupt was enabled, disable it first */
+	enabled = gic_peek_irq(d, GICD_ISENABLER);
+	if (enabled)
+		gic_mask_irq(d);
+
+	reg = gic_dist_base(d) + GICD_IROUTER + (gic_irq(d) * 8);
+	val = gic_mpidr_to_affinity(cpu_logical_map(cpu));
+
+	writeq_relaxed(val, reg);
+
+	/*
+	 * If the interrupt was enabled, enabled it again. Otherwise,
+	 * just wait for the distributor to have digested our changes.
+	 */
+	if (enabled)
+		gic_unmask_irq(d);
+	else
+		gic_dist_wait_for_rwp();
+
+	return IRQ_SET_MASK_OK;
+}
+#else
+#define gic_set_affinity	NULL
+#define gic_smp_init()		do { } while(0)
+#endif
+
+static struct irq_chip gic_chip = {
+	.name			= "GICv3",
+	.irq_mask		= gic_mask_irq,
+	.irq_unmask		= gic_unmask_irq,
+	.irq_eoi		= gic_eoi_irq,
+	.irq_set_type		= gic_set_type,
+	.irq_set_affinity	= gic_set_affinity,
+};
+
+static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
+				irq_hw_number_t hw)
+{
+	if (hw < 32) {
+		irq_set_percpu_devid(irq);
+		irq_set_chip_and_handler(irq, &gic_chip,
+					 handle_percpu_devid_irq);
+		set_irq_flags(irq, IRQF_VALID | IRQF_NOAUTOEN);
+	} else {
+		irq_set_chip_and_handler(irq, &gic_chip,
+					 handle_fasteoi_irq);
+		set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+	}
+	irq_set_chip_data(irq, d->host_data);
+	return 0;
+}
+
+static const struct irq_domain_ops gic_irq_domain_ops = {
+	.map = gic_irq_domain_map,
+	.xlate = gic_irq_domain_xlate,
+};
+
+static int __init gic_of_init(struct device_node *node, struct device_node *parent)
+{
+	void __iomem *dist_base;
+	void __iomem **redist_base;
+	u64 redist_stride;
+	u32 redist_regions;
+	u32 reg;
+	int gic_irqs;
+	int err;
+	int i;
+
+	dist_base = of_iomap(node, 0);
+	if (!dist_base) {
+		pr_err("%s: unable to map gic dist registers\n",
+			node->full_name);
+		return -ENXIO;
+	}
+
+	reg = readl_relaxed(dist_base + GICD_PIDR2) & GIC_PIDR2_ARCH_MASK;
+	if (reg != 0x30 && reg != 0x40) {
+		pr_err("%s: no distributor detected, giving up\n",
+			node->full_name);
+		err = -ENODEV;
+		goto out_unmap_dist;
+	}
+
+	if (of_property_read_u32(node, "#redistributor-regions", &redist_regions))
+		redist_regions = 1;
+
+	redist_base = kzalloc(sizeof(*redist_base) * redist_regions, GFP_KERNEL);
+	if (!redist_base) {
+		err = -ENOMEM;
+		goto out_unmap_dist;
+	}
+
+	for (i = 0; i < redist_regions; i++) {
+		redist_base[i] = of_iomap(node, 1 + i);
+		if (!redist_base[i]) {
+			pr_err("%s: couldn't map region %d\n",
+			       node->full_name, i);
+			err = -ENODEV;
+			goto out_unmap_rdist;
+		}
+	}
+
+	if (of_property_read_u64(node, "redistributor-stride", &redist_stride))
+		redist_stride = 0;
+
+	gic_data.dist_base = dist_base;
+	gic_data.redist_base = redist_base;
+	gic_data.redist_regions = redist_regions;
+	gic_data.redist_stride = redist_stride;
+
+	/*
+	 * Find out how many interrupts are supported.
+	 * The GIC only supports up to 1020 interrupt sources (SGI+PPI+SPI)
+	 */
+	gic_irqs = readl_relaxed(gic_data.dist_base + GICD_TYPER) & 0x1f;
+	gic_irqs = (gic_irqs + 1) * 32;
+	if (gic_irqs > 1020)
+		gic_irqs = 1020;
+	gic_data.irq_nr = gic_irqs;
+
+	gic_data.domain = irq_domain_add_linear(node, gic_irqs - 16,
+						&gic_irq_domain_ops, &gic_data);
+	gic_data.rdist = alloc_percpu(typeof(*gic_data.rdist));
+
+	if (WARN_ON(!gic_data.domain) || WARN_ON(!gic_data.rdist)) {
+		err = -ENOMEM;
+		goto out_free;
+	}
+
+	set_handle_irq(gic_handle_irq);
+
+	gic_smp_init();
+	gic_dist_init();
+	gic_cpu_init();
+
+	return 0;
+
+out_free:
+	if (gic_data.domain)
+		irq_domain_remove(gic_data.domain);
+	free_percpu(gic_data.rdist);
+out_unmap_rdist:
+	for (i = 0; i < redist_regions; i++)
+		if (redist_base[i])
+			iounmap(redist_base[i]);
+	kfree(redist_base);
+out_unmap_dist:
+	iounmap(dist_base);
+	return err;
+}
+
+IRQCHIP_DECLARE(gic_v3, "arm,gic-v3", gic_of_init);
diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h
new file mode 100644
index 0000000..16c8b05
--- /dev/null
+++ b/include/linux/irqchip/arm-gic-v3.h
@@ -0,0 +1,188 @@ 
+/*
+ * Copyright (C) 2013, 2014 ARM Limited, All Rights Reserved.
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ *
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __LINUX_IRQCHIP_ARM_GIC_V3_H
+#define __LINUX_IRQCHIP_ARM_GIC_V3_H
+
+/*
+ * Distributor registers. We assume we're running non-secure, with ARE
+ * being set. Secure-only and non-ARE registers are not described.
+ */
+#define GICD_CTLR			0x0000
+#define GICD_TYPER			0x0004
+#define GICD_IIDR			0x0008
+#define GICD_STATUSR			0x0010
+#define GICD_SETSPI_NSR			0x0040
+#define GICD_CLRSPI_NSR			0x0048
+#define GICD_SETSPI_SR			0x0050
+#define GICD_CLRSPI_SR			0x0058
+#define GICD_SEIR			0x0068
+#define GICD_ISENABLER			0x0100
+#define GICD_ICENABLER			0x0180
+#define GICD_ISPENDR			0x0200
+#define GICD_ICPENDR			0x0280
+#define GICD_ISACTIVER			0x0300
+#define GICD_ICACTIVER			0x0380
+#define GICD_IPRIORITYR			0x0400
+#define GICD_ICFGR			0x0C00
+#define GICD_IROUTER			0x6000
+#define GICD_PIDR2			0xFFE8
+
+#define GICD_CTLR_RWP			(1U << 31)
+#define GICD_CTLR_ARE_NS		(1U << 4)
+#define GICD_CTLR_ENABLE_G1A		(1U << 1)
+#define GICD_CTLR_ENABLE_G1		(1U << 0)
+
+#define GICD_IROUTER_SPI_MODE_ONE	(0U << 31)
+#define GICD_IROUTER_SPI_MODE_ANY	(1U << 31)
+
+#define GIC_PIDR2_ARCH_MASK		0xf0
+
+/*
+ * Re-Distributor registers, offsets from RD_base
+ */
+#define GICR_CTLR			GICD_CTLR
+#define GICR_IIDR			0x0004
+#define GICR_TYPER			0x0008
+#define GICR_STATUSR			GICD_STATUSR
+#define GICR_WAKER			0x0014
+#define GICR_SETLPIR			0x0040
+#define GICR_CLRLPIR			0x0048
+#define GICR_SEIR			GICD_SEIR
+#define GICR_PROPBASER			0x0070
+#define GICR_PENDBASER			0x0078
+#define GICR_INVLPIR			0x00A0
+#define GICR_INVALLR			0x00B0
+#define GICR_SYNCR			0x00C0
+#define GICR_MOVLPIR			0x0100
+#define GICR_MOVALLR			0x0110
+#define GICR_PIDR2			GICD_PIDR2
+
+#define GICR_WAKER_ProcessorSleep	(1U << 1)
+#define GICR_WAKER_ChildrenAsleep	(1U << 2)
+
+/*
+ * Re-Distributor registers, offsets from SGI_base
+ */
+#define GICR_ISENABLER0			GICD_ISENABLER
+#define GICR_ICENABLER0			GICD_ICENABLER
+#define GICR_ISPENDR0			GICD_ISPENDR
+#define GICR_ICPENDR0			GICD_ICPENDR
+#define GICR_ISACTIVER0			GICD_ISACTIVER
+#define GICR_ICACTIVER0			GICD_ICACTIVER
+#define GICR_IPRIORITYR0		GICD_IPRIORITYR
+#define GICR_ICFGR0			GICD_ICFGR
+
+#define GICR_TYPER_VLPIS		(1U << 1)
+#define GICR_TYPER_LAST			(1U << 4)
+
+/*
+ * CPU interface registers
+ */
+#define GICC_CTLR_EL1_EOImode_drop_dir	(0U << 1)
+#define GICC_CTLR_EL1_EOImode_drop	(1U << 1)
+#define GICC_SRE_EL1_SRE		(1U << 0)
+
+/*
+ * Hypervisor interface registers (SRE only)
+ */
+#define GICH_LR_VIRTUAL_ID_MASK		((1UL << 32) - 1)
+
+#define GICH_LR_EOI			(1UL << 41)
+#define GICH_LR_GROUP			(1UL << 60)
+#define GICH_LR_STATE			(3UL << 62)
+#define GICH_LR_PENDING_BIT		(1UL << 62)
+#define GICH_LR_ACTIVE_BIT		(1UL << 63)
+
+#define GICH_MISR_EOI			(1 << 0)
+#define GICH_MISR_U			(1 << 1)
+
+#define GICH_HCR_EN			(1 << 0)
+#define GICH_HCR_UIE			(1 << 1)
+
+#define GICH_VMCR_CTLR_SHIFT		0
+#define GICH_VMCR_CTLR_MASK		(0x21f << GICH_VMCR_CTLR_SHIFT)
+#define GICH_VMCR_BPR1_SHIFT		18
+#define GICH_VMCR_BPR1_MASK		(7 << GICH_VMCR_BPR1_SHIFT)
+#define GICH_VMCR_BPR0_SHIFT		21
+#define GICH_VMCR_BPR0_MASK		(7 << GICH_VMCR_BPR0_SHIFT)
+#define GICH_VMCR_PMR_SHIFT		24
+#define GICH_VMCR_PMR_MASK		(0xffUL << GICH_VMCR_PMR_SHIFT)
+
+#define ICC_EOIR1_EL1			S3_0_C12_C12_1
+#define ICC_IAR1_EL1			S3_0_C12_C12_0
+#define ICC_SGI1R_EL1			S3_0_C12_C11_5
+#define ICC_PMR_EL1			S3_0_C4_C6_0
+#define ICC_CTLR_EL1			S3_0_C12_C12_4
+#define ICC_SRE_EL1			S3_0_C12_C12_5
+#define ICC_GRPEN1_EL1			S3_0_C12_C12_7
+
+#define ICC_SRE_EL2			S3_4_C12_C9_5
+
+#define ICH_VSEIR_EL2			S3_4_C12_C9_4
+#define ICH_HCR_EL2			S3_4_C12_C11_0
+#define ICH_VTR_EL2			S3_4_C12_C11_1
+#define ICH_MISR_EL2			S3_4_C12_C11_2
+#define ICH_EISR_EL2			S3_4_C12_C11_3
+#define ICH_ELSR_EL2			S3_4_C12_C11_5
+#define ICH_VMCR_EL2			S3_4_C12_C11_7
+
+#define __LR0_EL2(x)			S3_4_C12_C12_ ## x
+#define __LR8_EL2(x)			S3_4_C12_C13_ ## x
+
+#define ICH_LR0_EL2			__LR0_EL2(0)
+#define ICH_LR1_EL2			__LR0_EL2(1)
+#define ICH_LR2_EL2			__LR0_EL2(2)
+#define ICH_LR3_EL2			__LR0_EL2(3)
+#define ICH_LR4_EL2			__LR0_EL2(4)
+#define ICH_LR5_EL2			__LR0_EL2(5)
+#define ICH_LR6_EL2			__LR0_EL2(6)
+#define ICH_LR7_EL2			__LR0_EL2(7)
+#define ICH_LR8_EL2			__LR8_EL2(0)
+#define ICH_LR9_EL2			__LR8_EL2(1)
+#define ICH_LR10_EL2			__LR8_EL2(2)
+#define ICH_LR11_EL2			__LR8_EL2(3)
+#define ICH_LR12_EL2			__LR8_EL2(4)
+#define ICH_LR13_EL2			__LR8_EL2(5)
+#define ICH_LR14_EL2			__LR8_EL2(6)
+#define ICH_LR15_EL2			__LR8_EL2(7)
+
+#define __AP0Rx_EL2(x)			S3_4_C12_C8_ ## x
+#define ICH_AP0R0_EL2			__AP0Rx_EL2(0)
+#define ICH_AP0R1_EL2			__AP0Rx_EL2(1)
+#define ICH_AP0R2_EL2			__AP0Rx_EL2(2)
+#define ICH_AP0R3_EL2			__AP0Rx_EL2(3)
+
+#define __AP1Rx_EL2(x)			S3_4_C12_C9_ ## x
+#define ICH_AP1R0_EL2			__AP1Rx_EL2(0)
+#define ICH_AP1R1_EL2			__AP1Rx_EL2(1)
+#define ICH_AP1R2_EL2			__AP1Rx_EL2(2)
+#define ICH_AP1R3_EL2			__AP1Rx_EL2(3)
+
+#ifndef __ASSEMBLY__
+
+#include <linux/stringify.h>
+
+static inline void gic_write_eoir(u64 irq)
+{
+	asm volatile("msr " __stringify(ICC_EOIR1_EL1) ", %0" : : "r" (irq));
+	isb();
+}
+
+#endif
+
+#endif