[PATCH v4 0/3] ARM: sun7i/sun6i: irqchip: Irqchip driver for NMI

[PATCH v4 0/3] ARM: sun7i/sun6i: irqchip: Irqchip driver for NMI

[Carlo Caione]

Allwinner A20/A31 SoCs have a special interrupt controller for managing NMI.
Three register are present to (un)mask, control and acknowledge NMI.
These two patches add a new irqchip driver in cascade with GIC.

Changes since v1:
	- added binding document

Changes since v2:
	- fixed trigger type in DTS
	- new explanations in binding documentation
	- added support for A31 (sun6i)

Changes since v3:
	- changed compatibles

Carlo Caione (3):
  ARM: sun7i/sun6i: irqchip: Add irqchip driver for NMI controller
  ARM: sun7i/sun6i: dts: Add NMI irqchip support
  ARM: sun7i/sun6i: irqchip: Update the documentation

 .../allwinner,sun67i-sc-nmi.txt                    |  27 +++
 arch/arm/boot/dts/sun6i-a31.dtsi                   |   9 +
 arch/arm/boot/dts/sun7i-a20.dtsi                   |   9 +
 drivers/irqchip/Makefile                           |   1 +
 drivers/irqchip/irq-sunxi-nmi.c                    | 228 +++++++++++++++++++++
 5 files changed, 274 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/interrupt-controller/allwinner,sun67i-sc-nmi.txt
 create mode 100644 drivers/irqchip/irq-sunxi-nmi.c

-- 
1.8.3.2

[PATCH v4 1/3] ARM: sun7i/sun6i: irqchip: Add irqchip driver for NMI controller

[Carlo Caione]

Allwinner A20/A31 SoCs have special registers to control / (un)mask /
acknowledge NMI. This NMI controller is separated and independent from GIC.
This patch adds a new irqchip to manage NMI.

Signed-off-by: Carlo Caione <carlo-KA+7E9HrN00dnm+yROfE0A@public.gmane.org>
---
 drivers/irqchip/Makefile        |   1 +
 drivers/irqchip/irq-sunxi-nmi.c | 228 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 229 insertions(+)
 create mode 100644 drivers/irqchip/irq-sunxi-nmi.c

diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index c60b901..e31d4d6 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_METAG_PERFCOUNTER_IRQS)	+= irq-metag.o
 obj-$(CONFIG_ARCH_MOXART)		+= irq-moxart.o
 obj-$(CONFIG_ORION_IRQCHIP)		+= irq-orion.o
 obj-$(CONFIG_ARCH_SUNXI)		+= irq-sun4i.o
+obj-$(CONFIG_ARCH_SUNXI)		+= irq-sunxi-nmi.o
 obj-$(CONFIG_ARCH_SPEAR3XX)		+= spear-shirq.o
 obj-$(CONFIG_ARM_GIC)			+= irq-gic.o
 obj-$(CONFIG_ARM_NVIC)			+= irq-nvic.o
diff --git a/drivers/irqchip/irq-sunxi-nmi.c b/drivers/irqchip/irq-sunxi-nmi.c
new file mode 100644
index 0000000..8796ae0
--- /dev/null
+++ b/drivers/irqchip/irq-sunxi-nmi.c
@@ -0,0 +1,228 @@
+/*
+ * Allwinner A20/A31 SoCs NMI IRQ chip driver.
+ *
+ * Carlo Caione <carlo.caione-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
+ *
+ * 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/bitops.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/irqdomain.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/irqchip/chained_irq.h>
+#include "irqchip.h"
+
+#define SUNXI_NMI_SRC_TYPE_MASK	0x00000003
+
+enum {
+	SUNXI_SRC_TYPE_LEVEL_LOW = 0,
+	SUNXI_SRC_TYPE_EDGE_FALLING,
+	SUNXI_SRC_TYPE_LEVEL_HIGH,
+	SUNXI_SRC_TYPE_EDGE_RISING,
+};
+
+struct sunxi_sc_nmi_reg_offs {
+	u32 ctrl;
+	u32 pend;
+	u32 enable;
+};
+
+static struct sunxi_sc_nmi_reg_offs sun7i_reg_offs = {
+	.ctrl	= 0x00,
+	.pend	= 0x04,
+	.enable	= 0x08,
+};
+
+static struct sunxi_sc_nmi_reg_offs sun6i_reg_offs = {
+	.ctrl	= 0x00,
+	.pend	= 0x04,
+	.enable	= 0x34,
+};
+
+/*
+ * Ack level interrupts right before unmask
+ *
+ * In case of level-triggered interrupt, IRQ line must be acked before it
+ * is unmasked or else a double-interrupt is triggered
+ */
+
+static void sunxi_sc_nmi_ack_and_unmask(struct irq_data *d)
+{
+	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
+	struct irq_chip_type *ct = irq_data_get_chip_type(d);
+	u32 mask = d->mask;
+
+	if (irqd_get_trigger_type(d) & IRQ_TYPE_LEVEL_MASK)
+		ct->chip.irq_ack(d);
+
+	irq_gc_lock(gc);
+	irq_reg_writel(mask, gc->reg_base + ct->regs.mask);
+	irq_gc_unlock(gc);
+}
+
+static inline void sunxi_sc_nmi_write(struct irq_chip_generic *gc, u32 off,
+				      u32 val)
+{
+	irq_reg_writel(val, gc->reg_base + off);
+}
+
+static inline u32 sunxi_sc_nmi_read(struct irq_chip_generic *gc, u32 off)
+{
+	return irq_reg_readl(gc->reg_base + off);
+}
+
+static void sunxi_sc_nmi_handle_irq(unsigned int irq, struct irq_desc *desc)
+{
+	struct irq_domain *domain = irq_desc_get_handler_data(desc);
+	struct irq_chip *chip = irq_get_chip(irq);
+	unsigned int virq = irq_find_mapping(domain, 0);
+
+	chained_irq_enter(chip, desc);
+	generic_handle_irq(virq);
+	chained_irq_exit(chip, desc);
+}
+
+static int sunxi_sc_nmi_set_type(struct irq_data *data, unsigned int flow_type)
+{
+	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data);
+	struct irq_chip_type *ct = gc->chip_types;
+	u32 src_type_reg;
+	u32 ctrl_off = ct->regs.type;
+	unsigned int src_type;
+	unsigned int i;
+
+	irq_gc_lock(gc);
+
+	switch (flow_type & IRQF_TRIGGER_MASK) {
+	case IRQ_TYPE_EDGE_FALLING:
+		src_type = SUNXI_SRC_TYPE_EDGE_FALLING;
+		break;
+	case IRQ_TYPE_EDGE_RISING:
+		src_type = SUNXI_SRC_TYPE_EDGE_RISING;
+		break;
+	case IRQ_TYPE_LEVEL_HIGH:
+		src_type = SUNXI_SRC_TYPE_LEVEL_HIGH;
+		break;
+	case IRQ_TYPE_NONE:
+	case IRQ_TYPE_LEVEL_LOW:
+		src_type = SUNXI_SRC_TYPE_LEVEL_LOW;
+		break;
+	default:
+		irq_gc_unlock(gc);
+		pr_err("%s: Cannot assign multiple trigger modes to IRQ %d.\n",
+			__func__, data->irq);
+		return -EBADR;
+	}
+
+	irqd_set_trigger_type(data, flow_type);
+	irq_setup_alt_chip(data, flow_type);
+
+	for (i = 0; i <= gc->num_ct; i++, ct++)
+		if (ct->type & flow_type)
+			ctrl_off = ct->regs.type;
+
+	src_type_reg = sunxi_sc_nmi_read(gc, ctrl_off);
+	src_type_reg &= ~SUNXI_NMI_SRC_TYPE_MASK;
+	src_type_reg |= src_type;
+	sunxi_sc_nmi_write(gc, ctrl_off, src_type_reg);
+
+	irq_gc_unlock(gc);
+
+	return IRQ_SET_MASK_OK;
+}
+
+static int __init sunxi_sc_nmi_irq_init(struct device_node *node,
+					struct sunxi_sc_nmi_reg_offs *reg_offs)
+{
+	struct irq_domain *domain;
+	struct irq_chip_generic *gc;
+	unsigned int irq;
+	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
+	int ret;
+
+
+	domain = irq_domain_add_linear(node, 1, &irq_generic_chip_ops, NULL);
+	if (!domain) {
+		pr_err("%s: Could not register interrupt domain.\n", node->name);
+		return -ENOMEM;
+	}
+
+	ret = irq_alloc_domain_generic_chips(domain, 1, 2, node->name,
+					     handle_level_irq, clr, 0,
+					     IRQ_GC_INIT_MASK_CACHE);
+	if (ret) {
+		 pr_err("%s: Could not allocate generic interrupt chip.\n",
+			 node->name);
+		 goto fail_irqd_remove;
+	}
+
+	irq = irq_of_parse_and_map(node, 0);
+	if (irq <= 0) {
+		pr_err("%s: unable to parse irq\n", node->name);
+		ret = -EINVAL;
+		goto fail_irqd_remove;
+	}
+
+	gc = irq_get_domain_generic_chip(domain, 0);
+	gc->reg_base = of_iomap(node, 0);
+	if (!gc->reg_base) {
+		pr_err("%s: unable to map resource\n", node->name);
+		ret = -ENOMEM;
+		goto fail_irqd_remove;
+	}
+
+	gc->chip_types[0].type			= IRQ_TYPE_LEVEL_MASK;
+	gc->chip_types[0].chip.irq_ack		= irq_gc_ack_set_bit;
+	gc->chip_types[0].chip.irq_mask		= irq_gc_mask_clr_bit;
+	gc->chip_types[0].chip.irq_unmask	= sunxi_sc_nmi_ack_and_unmask;
+	gc->chip_types[0].chip.irq_set_type	= sunxi_sc_nmi_set_type;
+	gc->chip_types[0].regs.ack		= reg_offs->pend;
+	gc->chip_types[0].regs.mask		= reg_offs->enable;
+	gc->chip_types[0].regs.type		= reg_offs->ctrl;
+
+	gc->chip_types[1].type			= IRQ_TYPE_EDGE_BOTH;
+	gc->chip_types[1].chip.name		= gc->chip_types[0].chip.name;
+	gc->chip_types[1].chip.irq_ack		= irq_gc_ack_set_bit;
+	gc->chip_types[1].chip.irq_mask		= irq_gc_mask_clr_bit;
+	gc->chip_types[1].chip.irq_unmask	= sunxi_sc_nmi_ack_and_unmask;
+	gc->chip_types[1].chip.irq_set_type	= sunxi_sc_nmi_set_type;
+	gc->chip_types[1].regs.ack		= reg_offs->pend;
+	gc->chip_types[1].regs.mask		= reg_offs->enable;
+	gc->chip_types[1].regs.type		= reg_offs->ctrl;
+	gc->chip_types[1].handler		= handle_edge_irq;
+
+	irq_set_handler_data(irq, domain);
+	irq_set_chained_handler(irq, sunxi_sc_nmi_handle_irq);
+
+	sunxi_sc_nmi_write(gc, reg_offs->enable, 0);
+	sunxi_sc_nmi_write(gc, reg_offs->pend, 0x1);
+
+	return 0;
+
+fail_irqd_remove:
+	irq_domain_remove(domain);
+
+	return ret;
+}
+
+static int __init sun6i_sc_nmi_irq_init(struct device_node *node,
+					struct device_node *parent)
+{
+	return sunxi_sc_nmi_irq_init(node, &sun6i_reg_offs);
+}
+IRQCHIP_DECLARE(sun6i_sc_nmi, "allwinner,sun6i-a31-sc-nmi", sun6i_sc_nmi_irq_init);
+
+static int __init sun7i_sc_nmi_irq_init(struct device_node *node,
+					struct device_node *parent)
+{
+	return sunxi_sc_nmi_irq_init(node, &sun7i_reg_offs);
+}
+IRQCHIP_DECLARE(sun7i_sc_nmi, "allwinner,sun7i-a20-sc-nmi", sun7i_sc_nmi_irq_init);
-- 
1.8.3.2

Re: [PATCH v4 1/3] ARM: sun7i/sun6i: irqchip: Add irqchip driver for NMI controller

[Maxime Ripard]

[-- Attachment #1: Type: text/plain, Size: 584 bytes --]

Hi Carlo,

On Thu, Feb 27, 2014 at 08:34:20PM +0100, Carlo Caione wrote:
> Allwinner A20/A31 SoCs have special registers to control / (un)mask /
> acknowledge NMI. This NMI controller is separated and independent from GIC.
> This patch adds a new irqchip to manage NMI.
> 
> Signed-off-by: Carlo Caione <carlo-KA+7E9HrN00dnm+yROfE0A@public.gmane.org>

Acked-by: Maxime Ripard <maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org>

Thanks!
Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

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[PATCH v4 2/3] ARM: sun7i/sun6i: dts: Add NMI irqchip support

[Carlo Caione]

This patch adds DTS entries for NMI controller as child of GIC.

Signed-off-by: Carlo Caione <carlo-KA+7E9HrN00dnm+yROfE0A@public.gmane.org>
---
 arch/arm/boot/dts/sun6i-a31.dtsi | 9 +++++++++
 arch/arm/boot/dts/sun7i-a20.dtsi | 9 +++++++++
 2 files changed, 18 insertions(+)

diff --git a/arch/arm/boot/dts/sun6i-a31.dtsi b/arch/arm/boot/dts/sun6i-a31.dtsi
index 5256ad9..4a5050c 100644
--- a/arch/arm/boot/dts/sun6i-a31.dtsi
+++ b/arch/arm/boot/dts/sun6i-a31.dtsi
@@ -190,6 +190,15 @@
 		#size-cells = <1>;
 		ranges;
 
+		nmi_intc: sc-nmi-intc@01f00c0c {
+			compatible = "allwinner,sun6i-a31-sc-nmi";
+			interrupt-controller;
+			#interrupt-cells = <2>;
+			reg = <0x01f00c0c 0x38>;
+			interrupt-parent = <&gic>;
+			interrupts = <0 0 4>;
+		};
+
 		pio: pinctrl@01c20800 {
 			compatible = "allwinner,sun6i-a31-pinctrl";
 			reg = <0x01c20800 0x400>;
diff --git a/arch/arm/boot/dts/sun7i-a20.dtsi b/arch/arm/boot/dts/sun7i-a20.dtsi
index 4c25f81..f01a23c 100644
--- a/arch/arm/boot/dts/sun7i-a20.dtsi
+++ b/arch/arm/boot/dts/sun7i-a20.dtsi
@@ -310,6 +310,15 @@
 		#size-cells = <1>;
 		ranges;
 
+		nmi_intc: sc-nmi-intc@01c00030 {
+			compatible = "allwinner,sun7i-a20-sc-nmi";
+			interrupt-controller;
+			#interrupt-cells = <2>;
+			reg = <0x01c00030 0x0c>;
+			interrupt-parent = <&gic>;
+			interrupts = <0 0 4>;
+		};
+
 		emac: ethernet@01c0b000 {
 			compatible = "allwinner,sun4i-emac";
 			reg = <0x01c0b000 0x1000>;
-- 
1.8.3.2

[PATCH v4 3/3] ARM: sun7i/sun6i: irqchip: Update the documentation

[Carlo Caione]

Added documentation for NMI irqchip.

Signed-off-by: Carlo Caione <carlo-KA+7E9HrN00dnm+yROfE0A@public.gmane.org>
---
 .../allwinner,sun67i-sc-nmi.txt                    | 27 ++++++++++++++++++++++
 1 file changed, 27 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/interrupt-controller/allwinner,sun67i-sc-nmi.txt

diff --git a/Documentation/devicetree/bindings/interrupt-controller/allwinner,sun67i-sc-nmi.txt b/Documentation/devicetree/bindings/interrupt-controller/allwinner,sun67i-sc-nmi.txt
new file mode 100644
index 0000000..ac31487
--- /dev/null
+++ b/Documentation/devicetree/bindings/interrupt-controller/allwinner,sun67i-sc-nmi.txt
@@ -0,0 +1,27 @@
+Allwinner Sunxi NMI Controller
+==============================
+
+Required properties:
+
+- compatible : should be "allwinner,sun7i-a20-sc-nmi" or
+  "allwinner,sun6i-a31-sc-nmi"
+- reg : Specifies base physical address and size of the registers.
+- interrupt-controller : Identifies the node as an interrupt controller
+- #interrupt-cells : Specifies the number of cells needed to encode an
+  interrupt source. The value shall be 2. The first cell is the IRQ number, the
+  second cell the trigger type.
+- interrupt-parent: Specifies the parent interrupt controller.
+- interrupts: Specifies the list of interrupt lines which are handled by
+  the interrupt controller in the parent controller's notation. This value
+  shall be the NMI.
+
+Example:
+
+sc-nmi-intc@01c00030 {
+	compatible = "allwinner,sun7i-a20-sc-nmi";
+	interrupt-controller;
+	#interrupt-cells = <2>;
+	reg = <0x01c00030 0x0c>;
+	interrupt-parent = <&gic>;
+	interrupts = <0 0 4>;
+};
-- 
1.8.3.2

Re: [PATCH v4 3/3] ARM: sun7i/sun6i: irqchip: Update the documentation

[Maxime Ripard]

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Hi,

On Thu, Feb 27, 2014 at 08:34:22PM +0100, Carlo Caione wrote:
> Added documentation for NMI irqchip.
> 
> Signed-off-by: Carlo Caione <carlo-KA+7E9HrN00dnm+yROfE0A@public.gmane.org>
> ---
>  .../allwinner,sun67i-sc-nmi.txt                    | 27 ++++++++++++++++++++++
>  1 file changed, 27 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/interrupt-controller/allwinner,sun67i-sc-nmi.txt
> 
> diff --git a/Documentation/devicetree/bindings/interrupt-controller/allwinner,sun67i-sc-nmi.txt b/Documentation/devicetree/bindings/interrupt-controller/allwinner,sun67i-sc-nmi.txt
> new file mode 100644
> index 0000000..ac31487
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/interrupt-controller/allwinner,sun67i-sc-nmi.txt
> @@ -0,0 +1,27 @@
> +Allwinner Sunxi NMI Controller
> +==============================
> +
> +Required properties:
> +
> +- compatible : should be "allwinner,sun7i-a20-sc-nmi" or
> +  "allwinner,sun6i-a31-sc-nmi"
> +- reg : Specifies base physical address and size of the registers.
> +- interrupt-controller : Identifies the node as an interrupt controller
> +- #interrupt-cells : Specifies the number of cells needed to encode an
> +  interrupt source. The value shall be 2. The first cell is the IRQ number, the
> +  second cell the trigger type.

What values correspond to what trigger type? What are the accepted values?

> +- interrupt-parent: Specifies the parent interrupt controller.
> +- interrupts: Specifies the list of interrupt lines which are handled by
> +  the interrupt controller in the parent controller's notation. This value
> +  shall be the NMI.

Hmmm, there's only one interrupt, not a list of them.

> +
> +Example:
> +
> +sc-nmi-intc@01c00030 {
> +	compatible = "allwinner,sun7i-a20-sc-nmi";
> +	interrupt-controller;
> +	#interrupt-cells = <2>;
> +	reg = <0x01c00030 0x0c>;
> +	interrupt-parent = <&gic>;
> +	interrupts = <0 0 4>;
> +};
> -- 
> 1.8.3.2
> 

Thanks!
Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

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Re: Re: [PATCH v4 3/3] ARM: sun7i/sun6i: irqchip: Update the documentation

[Carlo Caione]

On Mon, Mar 3, 2014 at 12:02 PM, Maxime Ripard
<maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org> wrote:
> Hi,
>
> On Thu, Feb 27, 2014 at 08:34:22PM +0100, Carlo Caione wrote:
>> Added documentation for NMI irqchip.
>>
>> Signed-off-by: Carlo Caione <carlo-KA+7E9HrN00dnm+yROfE0A@public.gmane.org>
>> ---
>>  .../allwinner,sun67i-sc-nmi.txt                    | 27 ++++++++++++++++++++++
>>  1 file changed, 27 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/interrupt-controller/allwinner,sun67i-sc-nmi.txt
>>
>> diff --git a/Documentation/devicetree/bindings/interrupt-controller/allwinner,sun67i-sc-nmi.txt b/Documentation/devicetree/bindings/interrupt-controller/allwinner,sun67i-sc-nmi.txt
>> new file mode 100644
>> index 0000000..ac31487
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/interrupt-controller/allwinner,sun67i-sc-nmi.txt
>> @@ -0,0 +1,27 @@
>> +Allwinner Sunxi NMI Controller
>> +==============================
>> +
>> +Required properties:
>> +
>> +- compatible : should be "allwinner,sun7i-a20-sc-nmi" or
>> +  "allwinner,sun6i-a31-sc-nmi"
>> +- reg : Specifies base physical address and size of the registers.
>> +- interrupt-controller : Identifies the node as an interrupt controller
>> +- #interrupt-cells : Specifies the number of cells needed to encode an
>> +  interrupt source. The value shall be 2. The first cell is the IRQ number, the
>> +  second cell the trigger type.
>
> What values correspond to what trigger type? What are the accepted values?
>
>> +- interrupt-parent: Specifies the parent interrupt controller.
>> +- interrupts: Specifies the list of interrupt lines which are handled by
>> +  the interrupt controller in the parent controller's notation. This value
>> +  shall be the NMI.
>
> Hmmm, there's only one interrupt, not a list of them.

Fix for both in v5.

Thank you,

-- 
Carlo Caione