1 files changed, 180 insertions, 0 deletions

diff --git a/kernel/arch/powerpc/platforms/82xx/pq2ads-pci-pic.c b/kernel/arch/powerpc/platforms/82xx/pq2ads-pci-pic.c
new file mode 100644
index 000000000..74861a7fb
--- /dev/null
+++ b/kernel/arch/powerpc/platforms/82xx/pq2ads-pci-pic.c
@@ -0,0 +1,180 @@
+/*
+ * PQ2 ADS-style PCI interrupt controller
+ *
+ * Copyright 2007 Freescale Semiconductor, Inc.
+ * Author: Scott Wood <scottwood@freescale.com>
+ *
+ * Loosely based on mpc82xx ADS support by Vitaly Bordug <vbordug@ru.mvista.com>
+ * Copyright (c) 2006 MontaVista Software, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/irq.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+
+#include <asm/io.h>
+#include <asm/prom.h>
+#include <asm/cpm2.h>
+
+#include "pq2.h"
+
+static DEFINE_RAW_SPINLOCK(pci_pic_lock);
+
+struct pq2ads_pci_pic {
+	struct device_node *node;
+	struct irq_domain *host;
+
+	struct {
+		u32 stat;
+		u32 mask;
+	} __iomem *regs;
+};
+
+#define NUM_IRQS 32
+
+static void pq2ads_pci_mask_irq(struct irq_data *d)
+{
+	struct pq2ads_pci_pic *priv = irq_data_get_irq_chip_data(d);
+	int irq = NUM_IRQS - irqd_to_hwirq(d) - 1;
+
+	if (irq != -1) {
+		unsigned long flags;
+		raw_spin_lock_irqsave(&pci_pic_lock, flags);
+
+		setbits32(&priv->regs->mask, 1 << irq);
+		mb();
+
+		raw_spin_unlock_irqrestore(&pci_pic_lock, flags);
+	}
+}
+
+static void pq2ads_pci_unmask_irq(struct irq_data *d)
+{
+	struct pq2ads_pci_pic *priv = irq_data_get_irq_chip_data(d);
+	int irq = NUM_IRQS - irqd_to_hwirq(d) - 1;
+
+	if (irq != -1) {
+		unsigned long flags;
+
+		raw_spin_lock_irqsave(&pci_pic_lock, flags);
+		clrbits32(&priv->regs->mask, 1 << irq);
+		raw_spin_unlock_irqrestore(&pci_pic_lock, flags);
+	}
+}
+
+static struct irq_chip pq2ads_pci_ic = {
+	.name = "PQ2 ADS PCI",
+	.irq_mask = pq2ads_pci_mask_irq,
+	.irq_mask_ack = pq2ads_pci_mask_irq,
+	.irq_ack = pq2ads_pci_mask_irq,
+	.irq_unmask = pq2ads_pci_unmask_irq,
+	.irq_enable = pq2ads_pci_unmask_irq,
+	.irq_disable = pq2ads_pci_mask_irq
+};
+
+static void pq2ads_pci_irq_demux(unsigned int irq, struct irq_desc *desc)
+{
+	struct pq2ads_pci_pic *priv = irq_desc_get_handler_data(desc);
+	u32 stat, mask, pend;
+	int bit;
+
+	for (;;) {
+		stat = in_be32(&priv->regs->stat);
+		mask = in_be32(&priv->regs->mask);
+
+		pend = stat & ~mask;
+
+		if (!pend)
+			break;
+
+		for (bit = 0; pend != 0; ++bit, pend <<= 1) {
+			if (pend & 0x80000000) {
+				int virq = irq_linear_revmap(priv->host, bit);
+				generic_handle_irq(virq);
+			}
+		}
+	}
+}
+
+static int pci_pic_host_map(struct irq_domain *h, unsigned int virq,
+			    irq_hw_number_t hw)
+{
+	irq_set_status_flags(virq, IRQ_LEVEL);
+	irq_set_chip_data(virq, h->host_data);
+	irq_set_chip_and_handler(virq, &pq2ads_pci_ic, handle_level_irq);
+	return 0;
+}
+
+static const struct irq_domain_ops pci_pic_host_ops = {
+	.map = pci_pic_host_map,
+};
+
+int __init pq2ads_pci_init_irq(void)
+{
+	struct pq2ads_pci_pic *priv;
+	struct irq_domain *host;
+	struct device_node *np;
+	int ret = -ENODEV;
+	int irq;
+
+	np = of_find_compatible_node(NULL, NULL, "fsl,pq2ads-pci-pic");
+	if (!np) {
+		printk(KERN_ERR "No pci pic node in device tree.\n");
+		of_node_put(np);
+		goto out;
+	}
+
+	irq = irq_of_parse_and_map(np, 0);
+	if (irq == NO_IRQ) {
+		printk(KERN_ERR "No interrupt in pci pic node.\n");
+		of_node_put(np);
+		goto out;
+	}
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv) {
+		of_node_put(np);
+		ret = -ENOMEM;
+		goto out_unmap_irq;
+	}
+
+	/* PCI interrupt controller registers: status and mask */
+	priv->regs = of_iomap(np, 0);
+	if (!priv->regs) {
+		printk(KERN_ERR "Cannot map PCI PIC registers.\n");
+		goto out_free_kmalloc;
+	}
+
+	/* mask all PCI interrupts */
+	out_be32(&priv->regs->mask, ~0);
+	mb();
+
+	host = irq_domain_add_linear(np, NUM_IRQS, &pci_pic_host_ops, priv);
+	if (!host) {
+		ret = -ENOMEM;
+		goto out_unmap_regs;
+	}
+
+	priv->host = host;
+	irq_set_handler_data(irq, priv);
+	irq_set_chained_handler(irq, pq2ads_pci_irq_demux);
+
+	of_node_put(np);
+	return 0;
+
+out_unmap_regs:
+	iounmap(priv->regs);
+out_free_kmalloc:
+	kfree(priv);
+	of_node_put(np);
+out_unmap_irq:
+	irq_dispose_mapping(irq);
+out:
+	return ret;
+}