1 files changed, 263 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/embedded6xx/flipper-pic.c b/arch/powerpc/platforms/embedded6xx/flipper-pic.c
new file mode 100644
index 000000000000..c278bd3a8fec
--- /dev/null
+++ b/arch/powerpc/platforms/embedded6xx/flipper-pic.c
@@ -0,0 +1,263 @@
+/*
+ * arch/powerpc/platforms/embedded6xx/flipper-pic.c
+ *
+ * Nintendo GameCube/Wii "Flipper" interrupt controller support.
+ * Copyright (C) 2004-2009 The GameCube Linux Team
+ * Copyright (C) 2007,2008,2009 Albert Herranz
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ */
+#define DRV_MODULE_NAME "flipper-pic"
+#define pr_fmt(fmt) DRV_MODULE_NAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/of.h>
+#include <asm/io.h>
+
+#include "flipper-pic.h"
+
+#define FLIPPER_NR_IRQS         32
+
+/*
+ * Each interrupt has a corresponding bit in both
+ * the Interrupt Cause (ICR) and Interrupt Mask (IMR) registers.
+ *
+ * Enabling/disabling an interrupt line involves setting/clearing
+ * the corresponding bit in IMR.
+ * Except for the RSW interrupt, all interrupts get deasserted automatically
+ * when the source deasserts the interrupt.
+ */
+#define FLIPPER_ICR             0x00
+#define FLIPPER_ICR_RSS         (1<<16) /* reset switch state */
+
+#define FLIPPER_IMR             0x04
+
+#define FLIPPER_RESET           0x24
+
+
+/*
+ * IRQ chip hooks.
+ *
+ */
+
+static void flipper_pic_mask_and_ack(unsigned int virq)
+{
+        int irq = virq_to_hw(virq);
+        void __iomem *io_base = get_irq_chip_data(virq);
+        u32 mask = 1 << irq;
+
+        clrbits32(io_base + FLIPPER_IMR, mask);
+        /* this is at least needed for RSW */
+        out_be32(io_base + FLIPPER_ICR, mask);
+}
+
+static void flipper_pic_ack(unsigned int virq)
+{
+        int irq = virq_to_hw(virq);
+        void __iomem *io_base = get_irq_chip_data(virq);
+
+        /* this is at least needed for RSW */
+        out_be32(io_base + FLIPPER_ICR, 1 << irq);
+}
+
+static void flipper_pic_mask(unsigned int virq)
+{
+        int irq = virq_to_hw(virq);
+        void __iomem *io_base = get_irq_chip_data(virq);
+
+        clrbits32(io_base + FLIPPER_IMR, 1 << irq);
+}
+
+static void flipper_pic_unmask(unsigned int virq)
+{
+        int irq = virq_to_hw(virq);
+        void __iomem *io_base = get_irq_chip_data(virq);
+
+        setbits32(io_base + FLIPPER_IMR, 1 << irq);
+}
+
+
+static struct irq_chip flipper_pic = {
+        .name           = "flipper-pic",
+        .ack            = flipper_pic_ack,
+        .mask_ack       = flipper_pic_mask_and_ack,
+        .mask           = flipper_pic_mask,
+        .unmask         = flipper_pic_unmask,
+};
+
+/*
+ * IRQ host hooks.
+ *
+ */
+
+static struct irq_host *flipper_irq_host;
+
+static int flipper_pic_map(struct irq_host *h, unsigned int virq,
+                           irq_hw_number_t hwirq)
+{
+        set_irq_chip_data(virq, h->host_data);
+        irq_to_desc(virq)->status |= IRQ_LEVEL;
+        set_irq_chip_and_handler(virq, &flipper_pic, handle_level_irq);
+        return 0;
+}
+
+static void flipper_pic_unmap(struct irq_host *h, unsigned int irq)
+{
+        set_irq_chip_data(irq, NULL);
+        set_irq_chip(irq, NULL);
+}
+
+static int flipper_pic_match(struct irq_host *h, struct device_node *np)
+{
+        return 1;
+}
+
+
+static struct irq_host_ops flipper_irq_host_ops = {
+        .map = flipper_pic_map,
+        .unmap = flipper_pic_unmap,
+        .match = flipper_pic_match,
+};
+
+/*
+ * Platform hooks.
+ *
+ */
+
+static void __flipper_quiesce(void __iomem *io_base)
+{
+        /* mask and ack all IRQs */
+        out_be32(io_base + FLIPPER_IMR, 0x00000000);
+        out_be32(io_base + FLIPPER_ICR, 0xffffffff);
+}
+
+struct irq_host * __init flipper_pic_init(struct device_node *np)
+{
+        struct device_node *pi;
+        struct irq_host *irq_host = NULL;
+        struct resource res;
+        void __iomem *io_base;
+        int retval;
+
+        pi = of_get_parent(np);
+        if (!pi) {
+                pr_err("no parent found\n");
+                goto out;
+        }
+        if (!of_device_is_compatible(pi, "nintendo,flipper-pi")) {
+                pr_err("unexpected parent compatible\n");
+                goto out;
+        }
+
+        retval = of_address_to_resource(pi, 0, &res);
+        if (retval) {
+                pr_err("no io memory range found\n");
+                goto out;
+        }
+        io_base = ioremap(res.start, resource_size(&res));
+
+        pr_info("controller at 0x%08x mapped to 0x%p\n", res.start, io_base);
+
+        __flipper_quiesce(io_base);
+
+        irq_host = irq_alloc_host(np, IRQ_HOST_MAP_LINEAR, FLIPPER_NR_IRQS,
+                                  &flipper_irq_host_ops, -1);
+        if (!irq_host) {
+                pr_err("failed to allocate irq_host\n");
+                return NULL;
+        }
+
+        irq_host->host_data = io_base;
+
+out:
+        return irq_host;
+}
+
+unsigned int flipper_pic_get_irq(void)
+{
+        void __iomem *io_base = flipper_irq_host->host_data;
+        int irq;
+        u32 irq_status;
+
+        irq_status = in_be32(io_base + FLIPPER_ICR) &
+                     in_be32(io_base + FLIPPER_IMR);
+        if (irq_status == 0)
+                return NO_IRQ;  /* no more IRQs pending */
+
+        irq = __ffs(irq_status);
+        return irq_linear_revmap(flipper_irq_host, irq);
+}
+
+/*
+ * Probe function.
+ *
+ */
+
+void __init flipper_pic_probe(void)
+{
+        struct device_node *np;
+
+        np = of_find_compatible_node(NULL, NULL, "nintendo,flipper-pic");
+        BUG_ON(!np);
+
+        flipper_irq_host = flipper_pic_init(np);
+        BUG_ON(!flipper_irq_host);
+
+        irq_set_default_host(flipper_irq_host);
+
+        of_node_put(np);
+}
+
+/*
+ * Misc functions related to the flipper chipset.
+ *
+ */
+
+/**
+ * flipper_quiesce() - quiesce flipper irq controller
+ *
+ * Mask and ack all interrupt sources.
+ *
+ */
+void flipper_quiesce(void)
+{
+        void __iomem *io_base = flipper_irq_host->host_data;
+
+        __flipper_quiesce(io_base);
+}
+
+/*
+ * Resets the platform.
+ */
+void flipper_platform_reset(void)
+{
+        void __iomem *io_base;
+
+        if (flipper_irq_host && flipper_irq_host->host_data) {
+                io_base = flipper_irq_host->host_data;
+                out_8(io_base + FLIPPER_RESET, 0x00);
+        }
+}
+
+/*
+ * Returns non-zero if the reset button is pressed.
+ */
+int flipper_is_reset_button_pressed(void)
+{
+        void __iomem *io_base;
+        u32 icr;
+
+        if (flipper_irq_host && flipper_irq_host->host_data) {
+                io_base = flipper_irq_host->host_data;
+                icr = in_be32(io_base + FLIPPER_ICR);
+                return !(icr & FLIPPER_ICR_RSS);
+        }
+        return 0;
+}
+