3 files changed, 102 insertions, 0 deletions

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 7f8728984f44..43bed4e5c7ae 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -156,6 +156,13 @@ config PIC32_EVIC
         select GENERIC_IRQ_CHIP
         select IRQ_DOMAIN
 
+config JCORE_AIC
+        bool "J-Core integrated AIC"
+        depends on OF && (SUPERH || COMPILE_TEST)
+        select IRQ_DOMAIN
+        help
+          Support for the J-Core integrated AIC.
+
 config RENESAS_INTC_IRQPIN
         bool
         select IRQ_DOMAIN
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index 4c203b6b8163..ee7e3ca0ac23 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -40,6 +40,7 @@ obj-$(CONFIG_I8259)			+= irq-i8259.o
 obj-$(CONFIG_IMGPDC_IRQ)                += irq-imgpdc.o
 obj-$(CONFIG_IRQ_MIPS_CPU)              += irq-mips-cpu.o
 obj-$(CONFIG_SIRF_IRQ)                  += irq-sirfsoc.o
+obj-$(CONFIG_JCORE_AIC)                 += irq-jcore-aic.o
 obj-$(CONFIG_RENESAS_INTC_IRQPIN)       += irq-renesas-intc-irqpin.o
 obj-$(CONFIG_RENESAS_IRQC)              += irq-renesas-irqc.o
 obj-$(CONFIG_VERSATILE_FPGA_IRQ)        += irq-versatile-fpga.o
diff --git a/drivers/irqchip/irq-jcore-aic.c b/drivers/irqchip/irq-jcore-aic.c
new file mode 100644
index 000000000000..5e5e3bb7d3c7
--- /dev/null
+++ b/drivers/irqchip/irq-jcore-aic.c
@@ -0,0 +1,94 @@
+/*
+ * J-Core SoC AIC driver
+ *
+ * Copyright (C) 2015-2016 Smart Energy Instruments, Inc.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/irqchip.h>
+#include <linux/irqdomain.h>
+#include <linux/cpu.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define JCORE_AIC_MAX_HWIRQ     127
+#define JCORE_AIC1_MIN_HWIRQ    16
+#define JCORE_AIC2_MIN_HWIRQ    64
+
+#define JCORE_AIC1_INTPRI_REG   8
+
+static struct irq_chip jcore_aic;
+
+static int jcore_aic_irqdomain_map(struct irq_domain *d, unsigned int irq,
+                                   irq_hw_number_t hwirq)
+{
+        struct irq_chip *aic = d->host_data;
+
+        irq_set_chip_and_handler(irq, aic, handle_simple_irq);
+
+        return 0;
+}
+
+static const struct irq_domain_ops jcore_aic_irqdomain_ops = {
+        .map = jcore_aic_irqdomain_map,
+        .xlate = irq_domain_xlate_onecell,
+};
+
+static void noop(struct irq_data *data)
+{
+}
+
+int __init aic_irq_of_init(struct device_node *node, struct device_node *parent)
+{
+        unsigned min_irq = JCORE_AIC2_MIN_HWIRQ;
+        unsigned dom_sz = JCORE_AIC_MAX_HWIRQ+1;
+        struct irq_domain *domain;
+
+        pr_info("Initializing J-Core AIC\n");
+
+        /* AIC1 needs priority initialization to receive interrupts. */
+        if (of_device_is_compatible(node, "jcore,aic1")) {
+                unsigned cpu;
+
+                for_each_present_cpu(cpu) {
+                        void __iomem *base = of_iomap(node, cpu);
+
+                        if (!base) {
+                                pr_err("Unable to map AIC for cpu %u\n", cpu);
+                                return -ENOMEM;
+                        }
+                        __raw_writel(0xffffffff, base + JCORE_AIC1_INTPRI_REG);
+                        iounmap(base);
+                }
+                min_irq = JCORE_AIC1_MIN_HWIRQ;
+        }
+
+        /*
+         * The irq chip framework requires either mask/unmask or enable/disable
+         * function pointers to be provided, but the hardware does not have any
+         * such mechanism; the only interrupt masking is at the cpu level and
+         * it affects all interrupts. We provide dummy mask/unmask. The hardware
+         * handles all interrupt control and clears pending status when the cpu
+         * accepts the interrupt.
+         */
+        jcore_aic.irq_mask = noop;
+        jcore_aic.irq_unmask = noop;
+        jcore_aic.name = "AIC";
+
+        domain = irq_domain_add_linear(node, dom_sz, &jcore_aic_irqdomain_ops,
+                                       &jcore_aic);
+        if (!domain)
+                return -ENOMEM;
+        irq_create_strict_mappings(domain, min_irq, min_irq, dom_sz - min_irq);
+
+        return 0;
+}
+
+IRQCHIP_DECLARE(jcore_aic2, "jcore,aic2", aic_irq_of_init);
+IRQCHIP_DECLARE(jcore_aic1, "jcore,aic1", aic_irq_of_init);