[PATCH v2 1/5] irqchip: add support for Marvell Orion SoCs

Sebastian Hesselbarth
2013-05-02T23:48:35Z

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>
---
Note: This patch triggers a checkpatch warning for
WARNING: Avoid CamelCase: <handle_IRQ>

Changelog:
v1->v2:
- rename compatible string to "marvell,orion-intc" (Suggested by Jason Gunthorpe)
- request mem regions for irq base registers (Suggested by Jason Gunthorpe)
- make orion_handle_irq static (Suggested by Jason Gunthorpe)
- make use of IRQCHIP_DECLARE (Suggested by Jason Gunthorpe)

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: Russell King <linux@arm.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Cc: Jean-Francois Moine <moinejf@free.fr>
Cc: devicetree-discuss at lists.ozlabs.org
Cc: linux-doc at vger.kernel.org
Cc: linux-arm-kernel at lists.infradead.org
Cc: linux-kernel at vger.kernel.org
---
.../interrupt-controller/marvell,orion-intc.txt | 22 ++++
drivers/irqchip/Kconfig | 5 +
drivers/irqchip/Makefile | 1 +
drivers/irqchip/irq-orion.c | 133 ++++++++++++++++++++
4 files changed, 161 insertions(+)
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..9b7aee9
--- /dev/null
+++ b/Documentation/devicetree/bindings/interrupt-controller/marvell,orion-intc.txt
@@ -0,0 +1,22 @@
+Marvell Orion SoC 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>;
+ };
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index a350969..8da3559 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -2,6 +2,11 @@ config IRQCHIP
def_bool y
depends on OF_IRQ

+config IRQCHIP_ORION
+ bool
+ select IRQ_DOMAIN
+ select MULTI_IRQ_HANDLER
+
config ARM_GIC
bool
select IRQ_DOMAIN
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 10ef57f..2cad23d 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -5,6 +5,7 @@ obj-$(CONFIG_ARCH_EXYNOS) += exynos-combiner.o
obj-$(CONFIG_ARCH_MXS) += irq-mxs.o
obj-$(CONFIG_METAG) += irq-metag-ext.o
obj-$(CONFIG_METAG_PERFCOUNTER_IRQS) += irq-metag.o
+obj-$(CONFIG_IRQCHIP_ORION) += irq-orion.o
obj-$(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..21ebe6c
--- /dev/null
+++ b/drivers/irqchip/irq-orion.c
@@ -0,0 +1,133 @@
+/*
+ * 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"
+
+/* max number of handled irq register blocks */
+#define ORION_MAX_IRQREG 2
+
+#define ORION_IRQ_CAUSE 0x00
+#define ORION_IRQ_MASK 0x04
+#define ORION_IRQ_FIQ_MASK 0x08
+#define ORION_IRQ_ENDP_MASK 0x0c
+
+static void __iomem *orion_irq_base[ORION_MAX_IRQREG];
+static unsigned int orion_irq_regs;
+static struct irq_domain *orion_irq_domain;
+
+static asmlinkage void __exception_irq_entry orion_handle_irq(
+ struct pt_regs *regs)
+{
+ int n;
+ for (n = 0; n < orion_irq_regs; n++) {
+ u32 hwirq_base = n * 32;
+ u32 stat = readl_relaxed(orion_irq_base[n] + ORION_IRQ_CAUSE) &
+ readl_relaxed(orion_irq_base[n] + ORION_IRQ_MASK);
+ while (stat) {
+ u32 hwirq = ffs(stat) - 1;
+ u32 irq = irq_find_mapping(orion_irq_domain,
+ hwirq_base + hwirq);
+ handle_IRQ(irq, regs);
+ stat &= ~(1 << hwirq);
+ }
+ }
+}
+
+static void orion_irq_mask(struct irq_data *irqd)
+{
+ unsigned int irq = irqd_to_hwirq(irqd);
+ unsigned int irq_off = irq % 32;
+ int reg = irq / 32;
+ u32 val;
+
+ val = readl(orion_irq_base[reg] + ORION_IRQ_MASK);
+ writel(val & ~(1 << irq_off), orion_irq_base[reg] + ORION_IRQ_MASK);
+}
+
+static void orion_irq_unmask(struct irq_data *irqd)
+{
+ unsigned int irq = irqd_to_hwirq(irqd);
+ unsigned int irq_off = irq % 32;
+ int reg = irq / 32;
+ u32 val;
+
+ val = readl(orion_irq_base[reg] + ORION_IRQ_MASK);
+ writel(val | (1 << irq_off), orion_irq_base[reg] + ORION_IRQ_MASK);
+}
+
+static struct irq_chip orion_irq_chip = {
+ .name = "orion_irq",
+ .irq_mask = orion_irq_mask,
+ .irq_unmask = orion_irq_unmask,
+};
+
+static int orion_irq_map(struct irq_domain *d, unsigned int virq,
+ irq_hw_number_t hw)
+{
+ irq_set_chip_and_handler(virq, &orion_irq_chip,
+ handle_level_irq);
+ set_irq_flags(virq, IRQF_VALID | IRQF_PROBE);
+
+ return 0;
+}
+
+static struct irq_domain_ops orion_irq_ops = {
+ .map = orion_irq_map,
+ .xlate = irq_domain_xlate_onecell,
+};
+
+static int __init orion_of_init(struct device_node *np,
+ struct device_node *parent)
+{
+ int n;
+
+ for (n = 0; n < ORION_MAX_IRQREG; n++) {
+ struct resource r;
+
+ /* parsing reg property may fail silently here */
+ if (of_address_to_resource(np, n, &r))
+ continue;
+
+ if (!request_mem_region(r.start, resource_size(&r), np->name))
+ panic("%s: unable to request mem region %d",
+ np->full_name, n);
+
+ orion_irq_base[n] = ioremap(r.start, resource_size(&r));
+ if (!orion_irq_base[n])
+ panic("%s: unable to map resource %d",
+ np->full_name, n);
+
+ /* mask all interrupts */
+ writel(0, orion_irq_base[n] + ORION_IRQ_MASK);
+ orion_irq_regs++;
+ }
+
+ /* at least one irq reg must be set */
+ if (!orion_irq_regs)
+ panic("%s: unable to map IRQC registers\n", np->full_name);
+
+ orion_irq_domain = irq_domain_add_linear(np, orion_irq_regs * 32,
+ &orion_irq_ops, NULL);
+ if (!orion_irq_domain)
+ panic("%s: unable to create IRQ domain\n", np->full_name);
+
+ set_handle_irq(orion_handle_irq);
+
+ return 0;
+}
+IRQCHIP_DECLARE(orion_intc, "marvell,orion-intc", orion_of_init);
--
1.7.10.4