--- /dev/null
+/*
+ * 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 <linux/of_address.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(struct irq_data *d)
+{
+ int irq = irqd_to_hwirq(d);
+ void __iomem *io_base = irq_data_get_irq_chip_data(d);
+ 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(struct irq_data *d)
+{
+ int irq = irqd_to_hwirq(d);
+ void __iomem *io_base = irq_data_get_irq_chip_data(d);
+
+ /* this is at least needed for RSW */
+ out_be32(io_base + FLIPPER_ICR, 1 << irq);
+}
+
+static void flipper_pic_mask(struct irq_data *d)
+{
+ int irq = irqd_to_hwirq(d);
+ void __iomem *io_base = irq_data_get_irq_chip_data(d);
+
+ clrbits32(io_base + FLIPPER_IMR, 1 << irq);
+}
+
+static void flipper_pic_unmask(struct irq_data *d)
+{
+ int irq = irqd_to_hwirq(d);
+ void __iomem *io_base = irq_data_get_irq_chip_data(d);
+
+ setbits32(io_base + FLIPPER_IMR, 1 << irq);
+}
+
+
+static struct irq_chip flipper_pic = {
+ .name = "flipper-pic",
+ .irq_ack = flipper_pic_ack,
+ .irq_mask_ack = flipper_pic_mask_and_ack,
+ .irq_mask = flipper_pic_mask,
+ .irq_unmask = flipper_pic_unmask,
+};
+
+/*
+ * IRQ host hooks.
+ *
+ */
+
+static struct irq_domain *flipper_irq_host;
+
+static int flipper_pic_map(struct irq_domain *h, unsigned int virq,
+ irq_hw_number_t hwirq)
+{
+ irq_set_chip_data(virq, h->host_data);
+ irq_set_status_flags(virq, IRQ_LEVEL);
+ irq_set_chip_and_handler(virq, &flipper_pic, handle_level_irq);
+ return 0;
+}
+
+static int flipper_pic_match(struct irq_domain *h, struct device_node *np)
+{
+ return 1;
+}
+
+
+static const struct irq_domain_ops flipper_irq_domain_ops = {
+ .map = flipper_pic_map,
+ .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_domain * __init flipper_pic_init(struct device_node *np)
+{
+ struct device_node *pi;
+ struct irq_domain *irq_domain = 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_domain = irq_domain_add_linear(np, FLIPPER_NR_IRQS,
+ &flipper_irq_domain_ops, io_base);
+ if (!irq_domain) {
+ pr_err("failed to allocate irq_domain\n");
+ return NULL;
+ }
+
+out:
+ return irq_domain;
+}
+
+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;
+}
+
Code Review / kvmfornfv.git / blobdiff