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[v3,1/6] irqchip: add support for Marvell Orion SoCs

Message ID 1370536034-23956-2-git-send-email-sebastian.hesselbarth@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

Sebastian Hesselbarth June 6, 2013, 4:27 p.m. UTC
This patch adds an irqchip driver for the main interrupt controller found
on Marvell Orion SoCs (Kirkwood, Dove, Orion5x, Discovery Innovation).
Corresponding device tree documentation is also added.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
---
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Rob Landley <rob@landley.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: linux-doc@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
---
 .../interrupt-controller/marvell,orion-intc.txt    |   48 +++++
 drivers/irqchip/Kconfig                            |    5 +
 drivers/irqchip/Makefile                           |    1 +
 drivers/irqchip/irq-orion.c                        |  193 ++++++++++++++++++++
 4 files changed, 247 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/interrupt-controller/marvell,orion-intc.txt
 create mode 100644 drivers/irqchip/irq-orion.c

Comments

Thomas Gleixner June 11, 2013, 8:46 a.m. UTC | #1
On Thu, 6 Jun 2013, Sebastian Hesselbarth wrote:

> This patch adds an irqchip driver for the main interrupt controller found
> on Marvell Orion SoCs (Kirkwood, Dove, Orion5x, Discovery Innovation).
> Corresponding device tree documentation is also added.
> 
> Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Thomas Gleixner June 11, 2013, 1:30 p.m. UTC | #2
On Tue, 11 Jun 2013, Thomas Gleixner wrote:

> On Thu, 6 Jun 2013, Sebastian Hesselbarth wrote:
> 
> > This patch adds an irqchip driver for the main interrupt controller found
> > on Marvell Orion SoCs (Kirkwood, Dove, Orion5x, Discovery Innovation).
> > Corresponding device tree documentation is also added.
> > 
> > Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
> 
> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>

Second thoughts:

>+static void orion_bridge_irq_handler(unsigned int irq, struct irq_desc *desc)
>+{
>+	struct irq_domain *d = irq_get_handler_data(irq);
>+	struct irq_chip_generic *gc = irq_get_domain_generic_chip(d, irq);
>+	u32 stat = readl_relaxed(gc->reg_base + ORION_BRIDGE_IRQ_CAUSE) &
>+		gc->mask_cache;

In init you map the first irq of that chip and install the chain
handler for it. Now if that first irq fires, isn't that set in the
cause register as well? And what acks that first irq?

Thanks,

	tglx
Sebastian Hesselbarth June 11, 2013, 1:37 p.m. UTC | #3
On 06/11/13 15:30, Thomas Gleixner wrote:
> On Tue, 11 Jun 2013, Thomas Gleixner wrote:
>
>> On Thu, 6 Jun 2013, Sebastian Hesselbarth wrote:
>>
>>> This patch adds an irqchip driver for the main interrupt controller found
>>> on Marvell Orion SoCs (Kirkwood, Dove, Orion5x, Discovery Innovation).
>>> Corresponding device tree documentation is also added.
>>>
>>> Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
>>
>> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
>
> Second thoughts:
>
>> +static void orion_bridge_irq_handler(unsigned int irq, struct irq_desc *desc)
>> +{
>> +	struct irq_domain *d = irq_get_handler_data(irq);
>> +	struct irq_chip_generic *gc = irq_get_domain_generic_chip(d, irq);
>> +	u32 stat = readl_relaxed(gc->reg_base + ORION_BRIDGE_IRQ_CAUSE) &
>> +		gc->mask_cache;
>
> In init you map the first irq of that chip and install the chain
> handler for it. Now if that first irq fires, isn't that set in the
> cause register as well? And what acks that first irq?

It is "acked" by acking all unmasked bridge irqs.

Sebastian
Thomas Gleixner June 11, 2013, 1:45 p.m. UTC | #4
On Tue, 11 Jun 2013, Sebastian Hesselbarth wrote:

> On 06/11/13 15:30, Thomas Gleixner wrote:
> > On Tue, 11 Jun 2013, Thomas Gleixner wrote:
> > 
> > > On Thu, 6 Jun 2013, Sebastian Hesselbarth wrote:
> > > 
> > > > This patch adds an irqchip driver for the main interrupt controller
> > > > found
> > > > on Marvell Orion SoCs (Kirkwood, Dove, Orion5x, Discovery Innovation).
> > > > Corresponding device tree documentation is also added.
> > > > 
> > > > Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
> > > 
> > > Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
> > 
> > Second thoughts:
> > 
> > > +static void orion_bridge_irq_handler(unsigned int irq, struct irq_desc
> > > *desc)
> > > +{
> > > +	struct irq_domain *d = irq_get_handler_data(irq);
> > > +	struct irq_chip_generic *gc = irq_get_domain_generic_chip(d, irq);
> > > +	u32 stat = readl_relaxed(gc->reg_base + ORION_BRIDGE_IRQ_CAUSE) &
> > > +		gc->mask_cache;
> > 
> > In init you map the first irq of that chip and install the chain
> > handler for it. Now if that first irq fires, isn't that set in the
> > cause register as well? And what acks that first irq?
> 
> It is "acked" by acking all unmasked bridge irqs.

Ok. A comment would be nice.

But what about the bit in of that first irq in the cause register? If
it's set on entry you call generic_handle_irq() for that as well. So
if it's set you need to mask it in stat. If not, then it wants a
comment.

Thanks,

	tglx
Grant Likely June 11, 2013, 1:48 p.m. UTC | #5
On Thu,  6 Jun 2013 18:27:09 +0200, Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> wrote:
> This patch adds an irqchip driver for the main interrupt controller found
> on Marvell Orion SoCs (Kirkwood, Dove, Orion5x, Discovery Innovation).
> Corresponding device tree documentation is also added.
> 
> Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>

Looks reasonable to me.

Acked-by: Grant Likely <grant.likely@secretlab.ca>

> ---
> Cc: Grant Likely <grant.likely@linaro.org>
> Cc: Rob Herring <rob.herring@calxeda.com>
> Cc: Rob Landley <rob@landley.net>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: John Stultz <john.stultz@linaro.org>
> Cc: Russell King <linux@arm.linux.org.uk>
> Cc: Jason Cooper <jason@lakedaemon.net>
> Cc: Andrew Lunn <andrew@lunn.ch>
> Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
> Cc: Gregory Clement <gregory.clement@free-electrons.com>
> Cc: devicetree-discuss@lists.ozlabs.org
> Cc: linux-doc@vger.kernel.org
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-kernel@vger.kernel.org
> ---
>  .../interrupt-controller/marvell,orion-intc.txt    |   48 +++++
>  drivers/irqchip/Kconfig                            |    5 +
>  drivers/irqchip/Makefile                           |    1 +
>  drivers/irqchip/irq-orion.c                        |  193 ++++++++++++++++++++
>  4 files changed, 247 insertions(+), 0 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/interrupt-controller/marvell,orion-intc.txt
>  create mode 100644 drivers/irqchip/irq-orion.c
> 
> diff --git a/Documentation/devicetree/bindings/interrupt-controller/marvell,orion-intc.txt b/Documentation/devicetree/bindings/interrupt-controller/marvell,orion-intc.txt
> new file mode 100644
> index 0000000..2c11ac7
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/interrupt-controller/marvell,orion-intc.txt
> @@ -0,0 +1,48 @@
> +Marvell Orion SoC interrupt controllers
> +
> +* Main interrupt controller
> +
> +Required properties:
> +- compatible: shall be "marvell,orion-intc"
> +- reg: base address(es) of interrupt registers starting with CAUSE register
> +- interrupt-controller: identifies the node as an interrupt controller
> +- #interrupt-cells: number of cells to encode an interrupt source, shall be 1
> +
> +The interrupt sources map to the corresponding bits in the interrupt
> +registers, i.e.
> +- 0 maps to bit 0 of first base address,
> +- 1 maps to bit 1 of first base address,
> +- 32 maps to bit 0 of second base address, and so on.
> +
> +Example:
> +	intc: interrupt-controller {
> +		compatible = "marvell,orion-intc";
> +		interrupt-controller;
> +		#interrupt-cells = <1>;
> +		 /* Dove has 64 first level interrupts */
> +		reg = <0x20200 0x10>, <0x20210 0x10>;
> +	};
> +
> +* Bridge interrupt controller
> +
> +Required properties:
> +- compatible: shall be "marvell,orion-bridge-intc"
> +- reg: base address of bridge interrupt registers starting with CAUSE register
> +- interrupts: bridge interrupt of the main interrupt controller
> +- interrupt-controller: identifies the node as an interrupt controller
> +- #interrupt-cells: number of cells to encode an interrupt source, shall be 1
> +
> +Optional properties:
> +- marvell,#interrupts: number of interrupts provided by bridge interrupt
> +      controller, defaults to 32 if not set
> +
> +Example:
> +	bridge_intc: interrupt-controller {
> +		compatible = "marvell,orion-bridge-intc";
> +		interrupt-controller;
> +		#interrupt-cells = <1>;
> +		reg = <0x20110 0x8>;
> +		interrupts = <0>;
> +		/* Dove bridge provides 5 interrupts */
> +		marvell,#interrupts = <5>;
> +	};
> diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
> index 4a33351..68c3107 100644
> --- a/drivers/irqchip/Kconfig
> +++ b/drivers/irqchip/Kconfig
> @@ -25,6 +25,11 @@ config ARM_VIC_NR
>  	  The maximum number of VICs available in the system, for
>  	  power management.
>  
> +config ORION_IRQCHIP
> +	bool
> +	select IRQ_DOMAIN
> +	select MULTI_IRQ_HANDLER
> +
>  config RENESAS_INTC_IRQPIN
>  	bool
>  	select IRQ_DOMAIN
> diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
> index cda4cb5..55df3bd 100644
> --- a/drivers/irqchip/Makefile
> +++ b/drivers/irqchip/Makefile
> @@ -7,6 +7,7 @@ obj-$(CONFIG_ARCH_MXS)			+= irq-mxs.o
>  obj-$(CONFIG_ARCH_S3C24XX)		+= irq-s3c24xx.o
>  obj-$(CONFIG_METAG)			+= irq-metag-ext.o
>  obj-$(CONFIG_METAG_PERFCOUNTER_IRQS)	+= irq-metag.o
> +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
> diff --git a/drivers/irqchip/irq-orion.c b/drivers/irqchip/irq-orion.c
> new file mode 100644
> index 0000000..693ea20
> --- /dev/null
> +++ b/drivers/irqchip/irq-orion.c
> @@ -0,0 +1,193 @@
> +/*
> + * Marvell Orion SoCs IRQ chip driver.
> + *
> + * Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
> + *
> + * This file is licensed under the terms of the GNU General Public
> + * License version 2.  This program is licensed "as is" without any
> + * warranty of any kind, whether express or implied.
> + */
> +
> +#include <linux/io.h>
> +#include <linux/irq.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
> +#include <asm/exception.h>
> +#include <asm/mach/irq.h>
> +
> +#include "irqchip.h"
> +
> +/*
> + * Orion SoC main interrupt controller
> + */
> +
> +#define ORION_IRQS_PER_CHIP		32
> +
> +#define ORION_IRQ_CAUSE			0x00
> +#define ORION_IRQ_MASK			0x04
> +#define ORION_IRQ_FIQ_MASK		0x08
> +#define ORION_IRQ_ENDP_MASK		0x0c
> +
> +static struct irq_domain *orion_irq_domain;
> +
> +static asmlinkage void __exception_irq_entry orion_handle_irq(
> +	struct pt_regs *regs)
> +{
> +	struct irq_domain_chip_generic *dgc = orion_irq_domain->gc;
> +	int n, base = 0;
> +
> +	for (n = 0; n < dgc->num_chips; n++, base += ORION_IRQS_PER_CHIP) {
> +		struct irq_chip_generic *gc =
> +			irq_get_domain_generic_chip(orion_irq_domain, base);
> +		u32 stat = readl_relaxed(gc->reg_base + ORION_IRQ_CAUSE) &
> +			gc->mask_cache;
> +		while (stat) {
> +			u32 hwirq = ffs(stat) - 1;
> +			u32 irq = irq_find_mapping(orion_irq_domain,
> +						   gc->irq_base + hwirq);
> +			handle_IRQ(irq, regs);
> +			stat &= ~(1 << hwirq);
> +		}
> +	}
> +}
> +
> +static int __init orion_irq_init(struct device_node *np,
> +				 struct device_node *parent)
> +{
> +	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
> +	struct resource r;
> +	int n, ret, base, num_chips = 0;
> +
> +	/* count number of irq chips by valid reg addresses */
> +	while (of_address_to_resource(np, num_chips, &r) == 0)
> +		num_chips++;
> +
> +	orion_irq_domain = irq_domain_add_linear(np,
> +				num_chips * ORION_IRQS_PER_CHIP,
> +				&irq_generic_chip_ops, NULL);
> +	if (!orion_irq_domain)
> +		panic("%s: unable to add irq domain\n", np->name);
> +
> +	ret = irq_alloc_domain_generic_chips(orion_irq_domain,
> +				ORION_IRQS_PER_CHIP, 1, np->name,
> +				handle_level_irq, clr, 0,
> +				IRQ_GC_INIT_MASK_CACHE);
> +	if (ret)
> +		panic("%s: unable to alloc irq domain gc\n", np->name);
> +
> +	for (n = 0, base = 0; n < num_chips; n++, base += ORION_IRQS_PER_CHIP) {
> +		struct irq_chip_generic *gc =
> +			irq_get_domain_generic_chip(orion_irq_domain, base);
> +
> +		of_address_to_resource(np, n, &r);
> +
> +		if (!request_mem_region(r.start, resource_size(&r), np->name))
> +			panic("%s: unable to request mem region %d",
> +			      np->name, n);
> +
> +		gc->reg_base = ioremap(r.start, resource_size(&r));
> +		if (!gc->reg_base)
> +			panic("%s: unable to map resource %d", np->name, n);
> +
> +		gc->chip_types[0].regs.mask = ORION_IRQ_MASK;
> +		gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
> +		gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
> +
> +		/* mask all interrupts */
> +		writel(0, gc->reg_base + ORION_IRQ_MASK);
> +	}
> +
> +	set_handle_irq(orion_handle_irq);
> +
> +	return 0;
> +}
> +IRQCHIP_DECLARE(orion_intc, "marvell,orion-intc", orion_irq_init);
> +
> +/*
> + * Orion SoC bridge interrupt controller
> + */
> +
> +#define ORION_BRIDGE_IRQ_CAUSE	0x00
> +#define ORION_BRIDGE_IRQ_MASK	0x04
> +
> +static void orion_bridge_irq_handler(unsigned int irq, struct irq_desc *desc)
> +{
> +	struct irq_domain *d = irq_get_handler_data(irq);
> +	struct irq_chip_generic *gc = irq_get_domain_generic_chip(d, irq);
> +	u32 stat = readl_relaxed(gc->reg_base + ORION_BRIDGE_IRQ_CAUSE) &
> +		gc->mask_cache;
> +
> +	while (stat) {
> +		u32 hwirq = ffs(stat) - 1;
> +		generic_handle_irq(irq_find_mapping(d, gc->irq_base + hwirq));
> +		stat &= ~(1 << hwirq);
> +	}
> +}
> +
> +static int __init orion_bridge_irq_init(struct device_node *np,
> +					struct device_node *parent)
> +{
> +	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
> +	struct resource r;
> +	struct irq_domain *domain;
> +	struct irq_chip_generic *gc;
> +	int ret, irq, nrirqs = 32;
> +
> +	/* get optional number of interrupts provided */
> +	of_property_read_u32(np, "marvell,#interrupts", &nrirqs);
> +
> +	domain = irq_domain_add_linear(np, nrirqs,
> +				       &irq_generic_chip_ops, NULL);
> +	if (!domain) {
> +		pr_err("%s: unable to add irq domain\n", np->name);
> +		return -ENOMEM;
> +	}
> +
> +	ret = irq_alloc_domain_generic_chips(domain, nrirqs, 1, np->name,
> +			     handle_level_irq, clr, 0, IRQ_GC_INIT_MASK_CACHE);
> +	if (ret) {
> +		pr_err("%s: unable to alloc irq domain gc\n", np->name);
> +		return ret;
> +	}
> +
> +	ret = of_address_to_resource(np, 0, &r);
> +	if (ret) {
> +		pr_err("%s: unable to get resource\n", np->name);
> +		return ret;
> +	}
> +
> +	if (!request_mem_region(r.start, resource_size(&r), np->name)) {
> +		pr_err("%s: unable to request mem region\n", np->name);
> +		return -ENOMEM;
> +	}
> +
> +	irq = irq_of_parse_and_map(np, 0);
> +	if (irq <= 0) {
> +		pr_err("%s: unable to parse irq\n", np->name);
> +		return -EINVAL;
> +	}
> +
> +	gc = irq_get_domain_generic_chip(domain, 0);
> +	gc->reg_base = ioremap(r.start, resource_size(&r));
> +	if (!gc->reg_base) {
> +		pr_err("%s: unable to map resource\n", np->name);
> +		return -ENOMEM;
> +	}
> +
> +	gc->chip_types[0].regs.ack = ORION_BRIDGE_IRQ_CAUSE;
> +	gc->chip_types[0].regs.mask = ORION_BRIDGE_IRQ_MASK;
> +	gc->chip_types[0].chip.irq_ack = irq_gc_ack_clr_bit;
> +	gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
> +	gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
> +
> +	/* mask all interrupts */
> +	writel(0, gc->reg_base + ORION_BRIDGE_IRQ_MASK);
> +
> +	irq_set_handler_data(irq, domain);
> +	irq_set_chained_handler(irq, orion_bridge_irq_handler);
> +
> +	return 0;
> +}
> +IRQCHIP_DECLARE(orion_bridge_intc,
> +		"marvell,orion-bridge-intc", orion_bridge_irq_init);
> -- 
> 1.7.2.5
>
Sebastian Hesselbarth June 11, 2013, 2:08 p.m. UTC | #6
On 06/11/13 15:45, Thomas Gleixner wrote:
> On Tue, 11 Jun 2013, Sebastian Hesselbarth wrote:
>> On 06/11/13 15:30, Thomas Gleixner wrote:
>>> On Tue, 11 Jun 2013, Thomas Gleixner wrote:
>>>> On Thu, 6 Jun 2013, Sebastian Hesselbarth wrote:
>>>>> This patch adds an irqchip driver for the main interrupt controller
>>>>> found
>>>>> on Marvell Orion SoCs (Kirkwood, Dove, Orion5x, Discovery Innovation).
>>>>> Corresponding device tree documentation is also added.
>>>>>
>>>>> Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
>>>>
>>>> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
>>>
>>> Second thoughts:
>>>
>>>> +static void orion_bridge_irq_handler(unsigned int irq, struct irq_desc
>>>> *desc)
>>>> +{
>>>> +	struct irq_domain *d = irq_get_handler_data(irq);
>>>> +	struct irq_chip_generic *gc = irq_get_domain_generic_chip(d, irq);
>>>> +	u32 stat = readl_relaxed(gc->reg_base + ORION_BRIDGE_IRQ_CAUSE) &
>>>> +		gc->mask_cache;
>>>
>>> In init you map the first irq of that chip and install the chain
>>> handler for it. Now if that first irq fires, isn't that set in the
>>> cause register as well? And what acks that first irq?
>>
>> It is "acked" by acking all unmasked bridge irqs.
>
> Ok. A comment would be nice.
>
> But what about the bit in of that first irq in the cause register? If
> it's set on entry you call generic_handle_irq() for that as well. So
> if it's set you need to mask it in stat. If not, then it wants a
> comment.

I am not sure I can follow. orion_bridge_irq_init() maps the first
parent irq, i.e. hwirq 0 of orion_irq. The parent irq controller
clears that irq cause when all corresponding chained irqs are
cleared. The chained (bridge) irqs are cleared by
orion_bridge_irq_handler above.

I can put a note to the parent irqchip in orion_irq_init() that we
don't need to clear its cause register, if it is that what you mean?

Sebastian
Thomas Gleixner June 11, 2013, 2:13 p.m. UTC | #7
On Tue, 11 Jun 2013, Sebastian Hesselbarth wrote:
> On 06/11/13 15:45, Thomas Gleixner wrote:
> > But what about the bit in of that first irq in the cause register? If
> > it's set on entry you call generic_handle_irq() for that as well. So
> > if it's set you need to mask it in stat. If not, then it wants a
> > comment.
> 
> I am not sure I can follow. orion_bridge_irq_init() maps the first
> parent irq, i.e. hwirq 0 of orion_irq. The parent irq controller
> clears that irq cause when all corresponding chained irqs are
> cleared. The chained (bridge) irqs are cleared by
> orion_bridge_irq_handler above.

That makes sense. I got confused by:

        irq = irq_of_parse_and_map(np, 0);

but now I see that it's mapping irq 0 of the parent interrupt
controller. I'll add a comment before merging it.

Thanks,

	tglx
Sebastian Hesselbarth June 11, 2013, 2:17 p.m. UTC | #8
On 06/11/13 16:13, Thomas Gleixner wrote:
> On Tue, 11 Jun 2013, Sebastian Hesselbarth wrote:
>> On 06/11/13 15:45, Thomas Gleixner wrote:
>>> But what about the bit in of that first irq in the cause register? If
>>> it's set on entry you call generic_handle_irq() for that as well. So
>>> if it's set you need to mask it in stat. If not, then it wants a
>>> comment.
>>
>> I am not sure I can follow. orion_bridge_irq_init() maps the first
>> parent irq, i.e. hwirq 0 of orion_irq. The parent irq controller
>> clears that irq cause when all corresponding chained irqs are
>> cleared. The chained (bridge) irqs are cleared by
>> orion_bridge_irq_handler above.
>
> That makes sense. I got confused by:
>
>          irq = irq_of_parse_and_map(np, 0);
>
> but now I see that it's mapping irq 0 of the parent interrupt
> controller. I'll add a comment before merging it.

Great! Just to be sure: Please make that comment refer to just
"parent interrupt" but not specifically "parent interrupt 0".
It is 0 only for Dove, and irq_of_parse_and_map(np, 0) maps the
first passed irq.

Sebastian
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/interrupt-controller/marvell,orion-intc.txt b/Documentation/devicetree/bindings/interrupt-controller/marvell,orion-intc.txt
new file mode 100644
index 0000000..2c11ac7
--- /dev/null
+++ b/Documentation/devicetree/bindings/interrupt-controller/marvell,orion-intc.txt
@@ -0,0 +1,48 @@ 
+Marvell Orion SoC interrupt controllers
+
+* Main interrupt controller
+
+Required properties:
+- compatible: shall be "marvell,orion-intc"
+- reg: base address(es) of interrupt registers starting with CAUSE register
+- interrupt-controller: identifies the node as an interrupt controller
+- #interrupt-cells: number of cells to encode an interrupt source, shall be 1
+
+The interrupt sources map to the corresponding bits in the interrupt
+registers, i.e.
+- 0 maps to bit 0 of first base address,
+- 1 maps to bit 1 of first base address,
+- 32 maps to bit 0 of second base address, and so on.
+
+Example:
+	intc: interrupt-controller {
+		compatible = "marvell,orion-intc";
+		interrupt-controller;
+		#interrupt-cells = <1>;
+		 /* Dove has 64 first level interrupts */
+		reg = <0x20200 0x10>, <0x20210 0x10>;
+	};
+
+* Bridge interrupt controller
+
+Required properties:
+- compatible: shall be "marvell,orion-bridge-intc"
+- reg: base address of bridge interrupt registers starting with CAUSE register
+- interrupts: bridge interrupt of the main interrupt controller
+- interrupt-controller: identifies the node as an interrupt controller
+- #interrupt-cells: number of cells to encode an interrupt source, shall be 1
+
+Optional properties:
+- marvell,#interrupts: number of interrupts provided by bridge interrupt
+      controller, defaults to 32 if not set
+
+Example:
+	bridge_intc: interrupt-controller {
+		compatible = "marvell,orion-bridge-intc";
+		interrupt-controller;
+		#interrupt-cells = <1>;
+		reg = <0x20110 0x8>;
+		interrupts = <0>;
+		/* Dove bridge provides 5 interrupts */
+		marvell,#interrupts = <5>;
+	};
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 4a33351..68c3107 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -25,6 +25,11 @@  config ARM_VIC_NR
 	  The maximum number of VICs available in the system, for
 	  power management.
 
+config ORION_IRQCHIP
+	bool
+	select IRQ_DOMAIN
+	select MULTI_IRQ_HANDLER
+
 config RENESAS_INTC_IRQPIN
 	bool
 	select IRQ_DOMAIN
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index cda4cb5..55df3bd 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -7,6 +7,7 @@  obj-$(CONFIG_ARCH_MXS)			+= irq-mxs.o
 obj-$(CONFIG_ARCH_S3C24XX)		+= irq-s3c24xx.o
 obj-$(CONFIG_METAG)			+= irq-metag-ext.o
 obj-$(CONFIG_METAG_PERFCOUNTER_IRQS)	+= irq-metag.o
+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
diff --git a/drivers/irqchip/irq-orion.c b/drivers/irqchip/irq-orion.c
new file mode 100644
index 0000000..693ea20
--- /dev/null
+++ b/drivers/irqchip/irq-orion.c
@@ -0,0 +1,193 @@ 
+/*
+ * Marvell Orion SoCs IRQ chip driver.
+ *
+ * Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <asm/exception.h>
+#include <asm/mach/irq.h>
+
+#include "irqchip.h"
+
+/*
+ * Orion SoC main interrupt controller
+ */
+
+#define ORION_IRQS_PER_CHIP		32
+
+#define ORION_IRQ_CAUSE			0x00
+#define ORION_IRQ_MASK			0x04
+#define ORION_IRQ_FIQ_MASK		0x08
+#define ORION_IRQ_ENDP_MASK		0x0c
+
+static struct irq_domain *orion_irq_domain;
+
+static asmlinkage void __exception_irq_entry orion_handle_irq(
+	struct pt_regs *regs)
+{
+	struct irq_domain_chip_generic *dgc = orion_irq_domain->gc;
+	int n, base = 0;
+
+	for (n = 0; n < dgc->num_chips; n++, base += ORION_IRQS_PER_CHIP) {
+		struct irq_chip_generic *gc =
+			irq_get_domain_generic_chip(orion_irq_domain, base);
+		u32 stat = readl_relaxed(gc->reg_base + ORION_IRQ_CAUSE) &
+			gc->mask_cache;
+		while (stat) {
+			u32 hwirq = ffs(stat) - 1;
+			u32 irq = irq_find_mapping(orion_irq_domain,
+						   gc->irq_base + hwirq);
+			handle_IRQ(irq, regs);
+			stat &= ~(1 << hwirq);
+		}
+	}
+}
+
+static int __init orion_irq_init(struct device_node *np,
+				 struct device_node *parent)
+{
+	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
+	struct resource r;
+	int n, ret, base, num_chips = 0;
+
+	/* count number of irq chips by valid reg addresses */
+	while (of_address_to_resource(np, num_chips, &r) == 0)
+		num_chips++;
+
+	orion_irq_domain = irq_domain_add_linear(np,
+				num_chips * ORION_IRQS_PER_CHIP,
+				&irq_generic_chip_ops, NULL);
+	if (!orion_irq_domain)
+		panic("%s: unable to add irq domain\n", np->name);
+
+	ret = irq_alloc_domain_generic_chips(orion_irq_domain,
+				ORION_IRQS_PER_CHIP, 1, np->name,
+				handle_level_irq, clr, 0,
+				IRQ_GC_INIT_MASK_CACHE);
+	if (ret)
+		panic("%s: unable to alloc irq domain gc\n", np->name);
+
+	for (n = 0, base = 0; n < num_chips; n++, base += ORION_IRQS_PER_CHIP) {
+		struct irq_chip_generic *gc =
+			irq_get_domain_generic_chip(orion_irq_domain, base);
+
+		of_address_to_resource(np, n, &r);
+
+		if (!request_mem_region(r.start, resource_size(&r), np->name))
+			panic("%s: unable to request mem region %d",
+			      np->name, n);
+
+		gc->reg_base = ioremap(r.start, resource_size(&r));
+		if (!gc->reg_base)
+			panic("%s: unable to map resource %d", np->name, n);
+
+		gc->chip_types[0].regs.mask = ORION_IRQ_MASK;
+		gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
+		gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
+
+		/* mask all interrupts */
+		writel(0, gc->reg_base + ORION_IRQ_MASK);
+	}
+
+	set_handle_irq(orion_handle_irq);
+
+	return 0;
+}
+IRQCHIP_DECLARE(orion_intc, "marvell,orion-intc", orion_irq_init);
+
+/*
+ * Orion SoC bridge interrupt controller
+ */
+
+#define ORION_BRIDGE_IRQ_CAUSE	0x00
+#define ORION_BRIDGE_IRQ_MASK	0x04
+
+static void orion_bridge_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+	struct irq_domain *d = irq_get_handler_data(irq);
+	struct irq_chip_generic *gc = irq_get_domain_generic_chip(d, irq);
+	u32 stat = readl_relaxed(gc->reg_base + ORION_BRIDGE_IRQ_CAUSE) &
+		gc->mask_cache;
+
+	while (stat) {
+		u32 hwirq = ffs(stat) - 1;
+		generic_handle_irq(irq_find_mapping(d, gc->irq_base + hwirq));
+		stat &= ~(1 << hwirq);
+	}
+}
+
+static int __init orion_bridge_irq_init(struct device_node *np,
+					struct device_node *parent)
+{
+	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
+	struct resource r;
+	struct irq_domain *domain;
+	struct irq_chip_generic *gc;
+	int ret, irq, nrirqs = 32;
+
+	/* get optional number of interrupts provided */
+	of_property_read_u32(np, "marvell,#interrupts", &nrirqs);
+
+	domain = irq_domain_add_linear(np, nrirqs,
+				       &irq_generic_chip_ops, NULL);
+	if (!domain) {
+		pr_err("%s: unable to add irq domain\n", np->name);
+		return -ENOMEM;
+	}
+
+	ret = irq_alloc_domain_generic_chips(domain, nrirqs, 1, np->name,
+			     handle_level_irq, clr, 0, IRQ_GC_INIT_MASK_CACHE);
+	if (ret) {
+		pr_err("%s: unable to alloc irq domain gc\n", np->name);
+		return ret;
+	}
+
+	ret = of_address_to_resource(np, 0, &r);
+	if (ret) {
+		pr_err("%s: unable to get resource\n", np->name);
+		return ret;
+	}
+
+	if (!request_mem_region(r.start, resource_size(&r), np->name)) {
+		pr_err("%s: unable to request mem region\n", np->name);
+		return -ENOMEM;
+	}
+
+	irq = irq_of_parse_and_map(np, 0);
+	if (irq <= 0) {
+		pr_err("%s: unable to parse irq\n", np->name);
+		return -EINVAL;
+	}
+
+	gc = irq_get_domain_generic_chip(domain, 0);
+	gc->reg_base = ioremap(r.start, resource_size(&r));
+	if (!gc->reg_base) {
+		pr_err("%s: unable to map resource\n", np->name);
+		return -ENOMEM;
+	}
+
+	gc->chip_types[0].regs.ack = ORION_BRIDGE_IRQ_CAUSE;
+	gc->chip_types[0].regs.mask = ORION_BRIDGE_IRQ_MASK;
+	gc->chip_types[0].chip.irq_ack = irq_gc_ack_clr_bit;
+	gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
+	gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
+
+	/* mask all interrupts */
+	writel(0, gc->reg_base + ORION_BRIDGE_IRQ_MASK);
+
+	irq_set_handler_data(irq, domain);
+	irq_set_chained_handler(irq, orion_bridge_irq_handler);
+
+	return 0;
+}
+IRQCHIP_DECLARE(orion_bridge_intc,
+		"marvell,orion-bridge-intc", orion_bridge_irq_init);