--- /dev/null
+/*
+ * arch/powerpc/platforms/embedded6xx/hlwd-pic.c
+ *
+ * Nintendo Wii "Hollywood" interrupt controller support.
+ * Copyright (C) 2009 The GameCube Linux Team
+ * Copyright (C) 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 "hlwd-pic"
+#define pr_fmt(fmt) DRV_MODULE_NAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/irq.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <asm/io.h>
+
+#include "hlwd-pic.h"
+
+#define HLWD_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 asserting/clearing
+ * the corresponding bit in IMR. ACK'ing a request simply involves
+ * asserting the corresponding bit in ICR.
+ */
+#define HW_BROADWAY_ICR 0x00
+#define HW_BROADWAY_IMR 0x04
+
+
+/*
+ * IRQ chip hooks.
+ *
+ */
+
+static void hlwd_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 + HW_BROADWAY_IMR, mask);
+ out_be32(io_base + HW_BROADWAY_ICR, mask);
+}
+
+static void hlwd_pic_ack(struct irq_data *d)
+{
+ int irq = irqd_to_hwirq(d);
+ void __iomem *io_base = irq_data_get_irq_chip_data(d);
+
+ out_be32(io_base + HW_BROADWAY_ICR, 1 << irq);
+}
+
+static void hlwd_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 + HW_BROADWAY_IMR, 1 << irq);
+}
+
+static void hlwd_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 + HW_BROADWAY_IMR, 1 << irq);
+}
+
+
+static struct irq_chip hlwd_pic = {
+ .name = "hlwd-pic",
+ .irq_ack = hlwd_pic_ack,
+ .irq_mask_ack = hlwd_pic_mask_and_ack,
+ .irq_mask = hlwd_pic_mask,
+ .irq_unmask = hlwd_pic_unmask,
+};
+
+/*
+ * IRQ host hooks.
+ *
+ */
+
+static struct irq_domain *hlwd_irq_host;
+
+static int hlwd_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, &hlwd_pic, handle_level_irq);
+ return 0;
+}
+
+static const struct irq_domain_ops hlwd_irq_domain_ops = {
+ .map = hlwd_pic_map,
+};
+
+static unsigned int __hlwd_pic_get_irq(struct irq_domain *h)
+{
+ void __iomem *io_base = h->host_data;
+ int irq;
+ u32 irq_status;
+
+ irq_status = in_be32(io_base + HW_BROADWAY_ICR) &
+ in_be32(io_base + HW_BROADWAY_IMR);
+ if (irq_status == 0)
+ return NO_IRQ; /* no more IRQs pending */
+
+ irq = __ffs(irq_status);
+ return irq_linear_revmap(h, irq);
+}
+
+static void hlwd_pic_irq_cascade(unsigned int cascade_virq,
+ struct irq_desc *desc)
+{
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ struct irq_domain *irq_domain = irq_get_handler_data(cascade_virq);
+ unsigned int virq;
+
+ raw_spin_lock(&desc->lock);
+ chip->irq_mask(&desc->irq_data); /* IRQ_LEVEL */
+ raw_spin_unlock(&desc->lock);
+
+ virq = __hlwd_pic_get_irq(irq_domain);
+ if (virq != NO_IRQ)
+ generic_handle_irq(virq);
+ else
+ pr_err("spurious interrupt!\n");
+
+ raw_spin_lock(&desc->lock);
+ chip->irq_ack(&desc->irq_data); /* IRQ_LEVEL */
+ if (!irqd_irq_disabled(&desc->irq_data) && chip->irq_unmask)
+ chip->irq_unmask(&desc->irq_data);
+ raw_spin_unlock(&desc->lock);
+}
+
+/*
+ * Platform hooks.
+ *
+ */
+
+static void __hlwd_quiesce(void __iomem *io_base)
+{
+ /* mask and ack all IRQs */
+ out_be32(io_base + HW_BROADWAY_IMR, 0);
+ out_be32(io_base + HW_BROADWAY_ICR, 0xffffffff);
+}
+
+struct irq_domain *hlwd_pic_init(struct device_node *np)
+{
+ struct irq_domain *irq_domain;
+ struct resource res;
+ void __iomem *io_base;
+ int retval;
+
+ retval = of_address_to_resource(np, 0, &res);
+ if (retval) {
+ pr_err("no io memory range found\n");
+ return NULL;
+ }
+ io_base = ioremap(res.start, resource_size(&res));
+ if (!io_base) {
+ pr_err("ioremap failed\n");
+ return NULL;
+ }
+
+ pr_info("controller at 0x%08x mapped to 0x%p\n", res.start, io_base);
+
+ __hlwd_quiesce(io_base);
+
+ irq_domain = irq_domain_add_linear(np, HLWD_NR_IRQS,
+ &hlwd_irq_domain_ops, io_base);
+ if (!irq_domain) {
+ pr_err("failed to allocate irq_domain\n");
+ iounmap(io_base);
+ return NULL;
+ }
+
+ return irq_domain;
+}
+
+unsigned int hlwd_pic_get_irq(void)
+{
+ return __hlwd_pic_get_irq(hlwd_irq_host);
+}
+
+/*
+ * Probe function.
+ *
+ */
+
+void hlwd_pic_probe(void)
+{
+ struct irq_domain *host;
+ struct device_node *np;
+ const u32 *interrupts;
+ int cascade_virq;
+
+ for_each_compatible_node(np, NULL, "nintendo,hollywood-pic") {
+ interrupts = of_get_property(np, "interrupts", NULL);
+ if (interrupts) {
+ host = hlwd_pic_init(np);
+ BUG_ON(!host);
+ cascade_virq = irq_of_parse_and_map(np, 0);
+ irq_set_handler_data(cascade_virq, host);
+ irq_set_chained_handler(cascade_virq,
+ hlwd_pic_irq_cascade);
+ hlwd_irq_host = host;
+ break;
+ }
+ }
+}
+
+/**
+ * hlwd_quiesce() - quiesce hollywood irq controller
+ *
+ * Mask and ack all interrupt sources.
+ *
+ */
+void hlwd_quiesce(void)
+{
+ void __iomem *io_base = hlwd_irq_host->host_data;
+
+ __hlwd_quiesce(io_base);
+}
+
Code Review / kvmfornfv.git / blobdiff