powerpc: Add WSP platform

Add a platform for the Wire Speed Processor, based on the PPC A2.

This includes code for the ICS & OPB interrupt controllers, as well
as a SCOM backend, and SCOM based cpu bringup.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Jack Miller <jack@codezen.org>
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 712 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/wsp/ics.c b/arch/powerpc/platforms/wsp/ics.c
new file mode 100644
index 000000000000..e53bd9e7b125
--- /dev/null
+++ b/arch/powerpc/platforms/wsp/ics.c
@@ -0,0 +1,712 @@
+/*
+ * Copyright 2008-2011 IBM Corporation.
+ *
+ *  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.
+ */
+
+#include <linux/cpu.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/msi.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/smp.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/xics.h>
+
+#include "wsp.h"
+#include "ics.h"
+
+
+/* WSP ICS */
+
+struct wsp_ics {
+	struct ics ics;
+	struct device_node *dn;
+	void __iomem *regs;
+	spinlock_t lock;
+	unsigned long *bitmap;
+	u32 chip_id;
+	u32 lsi_base;
+	u32 lsi_count;
+	u64 hwirq_start;
+	u64 count;
+#ifdef CONFIG_SMP
+	int *hwirq_cpu_map;
+#endif
+};
+
+#define to_wsp_ics(ics)	container_of(ics, struct wsp_ics, ics)
+
+#define INT_SRC_LAYER_BUID_REG(base)	((base) + 0x00)
+#define IODA_TBL_ADDR_REG(base)		((base) + 0x18)
+#define IODA_TBL_DATA_REG(base)		((base) + 0x20)
+#define XIVE_UPDATE_REG(base)		((base) + 0x28)
+#define ICS_INT_CAPS_REG(base)		((base) + 0x30)
+
+#define TBL_AUTO_INCREMENT	((1UL << 63) | (1UL << 15))
+#define TBL_SELECT_XIST		(1UL << 48)
+#define TBL_SELECT_XIVT		(1UL << 49)
+
+#define IODA_IRQ(irq)		((irq) & (0x7FFULL))	/* HRM 5.1.3.4 */
+
+#define XIST_REQUIRED		0x8
+#define XIST_REJECTED		0x4
+#define XIST_PRESENTED		0x2
+#define XIST_PENDING		0x1
+
+#define XIVE_SERVER_SHIFT	42
+#define XIVE_SERVER_MASK	0xFFFFULL
+#define XIVE_PRIORITY_MASK	0xFFULL
+#define XIVE_PRIORITY_SHIFT	32
+#define XIVE_WRITE_ENABLE	(1ULL << 63)
+
+/*
+ * The docs refer to a 6 bit field called ChipID, which consists of a
+ * 3 bit NodeID and a 3 bit ChipID. On WSP the ChipID is always zero
+ * so we ignore it, and every where we use "chip id" in this code we
+ * mean the NodeID.
+ */
+#define WSP_ICS_CHIP_SHIFT		17
+
+
+static struct wsp_ics *ics_list;
+static int num_ics;
+
+/* ICS Source controller accessors */
+
+static u64 wsp_ics_get_xive(struct wsp_ics *ics, unsigned int irq)
+{
+	unsigned long flags;
+	u64 xive;
+
+	spin_lock_irqsave(&ics->lock, flags);
+	out_be64(IODA_TBL_ADDR_REG(ics->regs), TBL_SELECT_XIVT | IODA_IRQ(irq));
+	xive = in_be64(IODA_TBL_DATA_REG(ics->regs));
+	spin_unlock_irqrestore(&ics->lock, flags);
+
+	return xive;
+}
+
+static void wsp_ics_set_xive(struct wsp_ics *ics, unsigned int irq, u64 xive)
+{
+	xive &= ~XIVE_ADDR_MASK;
+	xive |= (irq & XIVE_ADDR_MASK);
+	xive |= XIVE_WRITE_ENABLE;
+
+	out_be64(XIVE_UPDATE_REG(ics->regs), xive);
+}
+
+static u64 xive_set_server(u64 xive, unsigned int server)
+{
+	u64 mask = ~(XIVE_SERVER_MASK << XIVE_SERVER_SHIFT);
+
+	xive &= mask;
+	xive |= (server & XIVE_SERVER_MASK) << XIVE_SERVER_SHIFT;
+
+	return xive;
+}
+
+static u64 xive_set_priority(u64 xive, unsigned int priority)
+{
+	u64 mask = ~(XIVE_PRIORITY_MASK << XIVE_PRIORITY_SHIFT);
+
+	xive &= mask;
+	xive |= (priority & XIVE_PRIORITY_MASK) << XIVE_PRIORITY_SHIFT;
+
+	return xive;
+}
+
+
+#ifdef CONFIG_SMP
+/* Find logical CPUs within mask on a given chip and store result in ret */
+void cpus_on_chip(int chip_id, cpumask_t *mask, cpumask_t *ret)
+{
+	int cpu, chip;
+	struct device_node *cpu_dn, *dn;
+	const u32 *prop;
+
+	cpumask_clear(ret);
+	for_each_cpu(cpu, mask) {
+		cpu_dn = of_get_cpu_node(cpu, NULL);
+		if (!cpu_dn)
+			continue;
+
+		prop = of_get_property(cpu_dn, "at-node", NULL);
+		if (!prop) {
+			of_node_put(cpu_dn);
+			continue;
+		}
+
+		dn = of_find_node_by_phandle(*prop);
+		of_node_put(cpu_dn);
+
+		chip = wsp_get_chip_id(dn);
+		if (chip == chip_id)
+			cpumask_set_cpu(cpu, ret);
+
+		of_node_put(dn);
+	}
+}
+
+/* Store a suitable CPU to handle a hwirq in the ics->hwirq_cpu_map cache */
+static int cache_hwirq_map(struct wsp_ics *ics, unsigned int hwirq,
+			   const cpumask_t *affinity)
+{
+	cpumask_var_t avail, newmask;
+	int ret = -ENOMEM, cpu, cpu_rover = 0, target;
+	int index = hwirq - ics->hwirq_start;
+	unsigned int nodeid;
+
+	BUG_ON(index < 0 || index >= ics->count);
+
+	if (!ics->hwirq_cpu_map)
+		return -ENOMEM;
+
+	if (!distribute_irqs) {
+		ics->hwirq_cpu_map[hwirq - ics->hwirq_start] = xics_default_server;
+		return 0;
+	}
+
+	/* Allocate needed CPU masks */
+	if (!alloc_cpumask_var(&avail, GFP_KERNEL))
+		goto ret;
+	if (!alloc_cpumask_var(&newmask, GFP_KERNEL))
+		goto freeavail;
+
+	/* Find PBus attached to the source of this IRQ */
+	nodeid = (hwirq >> WSP_ICS_CHIP_SHIFT) & 0x3; /* 12:14 */
+
+	/* Find CPUs that could handle this IRQ */
+	if (affinity)
+		cpumask_and(avail, cpu_online_mask, affinity);
+	else
+		cpumask_copy(avail, cpu_online_mask);
+
+	/* Narrow selection down to logical CPUs on the same chip */
+	cpus_on_chip(nodeid, avail, newmask);
+
+	/* Ensure we haven't narrowed it down to 0 */
+	if (unlikely(cpumask_empty(newmask))) {
+		if (unlikely(cpumask_empty(avail))) {
+			ret = -1;
+			goto out;
+		}
+		cpumask_copy(newmask, avail);
+	}
+
+	/* Choose a CPU out of those we narrowed it down to in round robin */
+	target = hwirq % cpumask_weight(newmask);
+	for_each_cpu(cpu, newmask) {
+		if (cpu_rover++ >= target) {
+			ics->hwirq_cpu_map[index] = get_hard_smp_processor_id(cpu);
+			ret = 0;
+			goto out;
+		}
+	}
+
+	/* Shouldn't happen */
+	WARN_ON(1);
+
+out:
+	free_cpumask_var(newmask);
+freeavail:
+	free_cpumask_var(avail);
+ret:
+	if (ret < 0) {
+		ics->hwirq_cpu_map[index] = cpumask_first(cpu_online_mask);
+		pr_warning("Error, falling hwirq 0x%x routing back to CPU %i\n",
+			   hwirq, ics->hwirq_cpu_map[index]);
+	}
+	return ret;
+}
+
+static void alloc_irq_map(struct wsp_ics *ics)
+{
+	int i;
+
+	ics->hwirq_cpu_map = kmalloc(sizeof(int) * ics->count, GFP_KERNEL);
+	if (!ics->hwirq_cpu_map) {
+		pr_warning("Allocate hwirq_cpu_map failed, "
+			   "IRQ balancing disabled\n");
+		return;
+	}
+
+	for (i=0; i < ics->count; i++)
+		ics->hwirq_cpu_map[i] = xics_default_server;
+}
+
+static int get_irq_server(struct wsp_ics *ics, unsigned int hwirq)
+{
+	int index = hwirq - ics->hwirq_start;
+
+	BUG_ON(index < 0 || index >= ics->count);
+
+	if (!ics->hwirq_cpu_map)
+		return xics_default_server;
+
+	return ics->hwirq_cpu_map[index];
+}
+#else /* !CONFIG_SMP */
+static int cache_hwirq_map(struct wsp_ics *ics, unsigned int hwirq,
+			   const cpumask_t *affinity)
+{
+	return 0;
+}
+
+static int get_irq_server(struct wsp_ics *ics, unsigned int hwirq)
+{
+	return xics_default_server;
+}
+
+static void alloc_irq_map(struct wsp_ics *ics) { }
+#endif
+
+static void wsp_chip_unmask_irq(struct irq_data *d)
+{
+	unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
+	struct wsp_ics *ics;
+	int server;
+	u64 xive;
+
+	if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS)
+		return;
+
+	ics = d->chip_data;
+	if (WARN_ON(!ics))
+		return;
+
+	server = get_irq_server(ics, hw_irq);
+
+	xive = wsp_ics_get_xive(ics, hw_irq);
+	xive = xive_set_server(xive, server);
+	xive = xive_set_priority(xive, DEFAULT_PRIORITY);
+	wsp_ics_set_xive(ics, hw_irq, xive);
+}
+
+static unsigned int wsp_chip_startup(struct irq_data *d)
+{
+	/* unmask it */
+	wsp_chip_unmask_irq(d);
+	return 0;
+}
+
+static void wsp_mask_real_irq(unsigned int hw_irq, struct wsp_ics *ics)
+{
+	u64 xive;
+
+	if (hw_irq == XICS_IPI)
+		return;
+
+	if (WARN_ON(!ics))
+		return;
+	xive = wsp_ics_get_xive(ics, hw_irq);
+	xive = xive_set_server(xive, xics_default_server);
+	xive = xive_set_priority(xive, LOWEST_PRIORITY);
+	wsp_ics_set_xive(ics, hw_irq, xive);
+}
+
+static void wsp_chip_mask_irq(struct irq_data *d)
+{
+	unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
+	struct wsp_ics *ics = d->chip_data;
+
+	if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS)
+		return;
+
+	wsp_mask_real_irq(hw_irq, ics);
+}
+
+static int wsp_chip_set_affinity(struct irq_data *d,
+				 const struct cpumask *cpumask, bool force)
+{
+	unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
+	struct wsp_ics *ics;
+	int ret;
+	u64 xive;
+
+	if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS)
+		return -1;
+
+	ics = d->chip_data;
+	if (WARN_ON(!ics))
+		return -1;
+	xive = wsp_ics_get_xive(ics, hw_irq);
+
+	/*
+	 * For the moment only implement delivery to all cpus or one cpu.
+	 * Get current irq_server for the given irq
+	 */
+	ret = cache_hwirq_map(ics, d->irq, cpumask);
+	if (ret == -1) {
+		char cpulist[128];
+		cpumask_scnprintf(cpulist, sizeof(cpulist), cpumask);
+		pr_warning("%s: No online cpus in the mask %s for irq %d\n",
+			   __func__, cpulist, d->irq);
+		return -1;
+	} else if (ret == -ENOMEM) {
+		pr_warning("%s: Out of memory\n", __func__);
+		return -1;
+	}
+
+	xive = xive_set_server(xive, get_irq_server(ics, hw_irq));
+	wsp_ics_set_xive(ics, hw_irq, xive);
+
+	return 0;
+}
+
+static struct irq_chip wsp_irq_chip = {
+	.name = "WSP ICS",
+	.irq_startup		= wsp_chip_startup,
+	.irq_mask		= wsp_chip_mask_irq,
+	.irq_unmask		= wsp_chip_unmask_irq,
+	.irq_set_affinity	= wsp_chip_set_affinity
+};
+
+static int wsp_ics_host_match(struct ics *ics, struct device_node *dn)
+{
+	/* All ICSs in the system implement a global irq number space,
+	 * so match against them all. */
+	return of_device_is_compatible(dn, "ibm,ppc-xics");
+}
+
+static int wsp_ics_match_hwirq(struct wsp_ics *wsp_ics, unsigned int hwirq)
+{
+	if (hwirq >= wsp_ics->hwirq_start &&
+	    hwirq <  wsp_ics->hwirq_start + wsp_ics->count)
+		return 1;
+
+	return 0;
+}
+
+static int wsp_ics_map(struct ics *ics, unsigned int virq)
+{
+	struct wsp_ics *wsp_ics = to_wsp_ics(ics);
+	unsigned int hw_irq = virq_to_hw(virq);
+	unsigned long flags;
+
+	if (!wsp_ics_match_hwirq(wsp_ics, hw_irq))
+		return -ENOENT;
+
+	irq_set_chip_and_handler(virq, &wsp_irq_chip, handle_fasteoi_irq);
+
+	irq_set_chip_data(virq, wsp_ics);
+
+	spin_lock_irqsave(&wsp_ics->lock, flags);
+	bitmap_allocate_region(wsp_ics->bitmap, hw_irq - wsp_ics->hwirq_start, 0);
+	spin_unlock_irqrestore(&wsp_ics->lock, flags);
+
+	return 0;
+}
+
+static void wsp_ics_mask_unknown(struct ics *ics, unsigned long hw_irq)
+{
+	struct wsp_ics *wsp_ics = to_wsp_ics(ics);
+
+	if (!wsp_ics_match_hwirq(wsp_ics, hw_irq))
+		return;
+
+	pr_err("%s: IRQ %lu (real) is invalid, disabling it.\n", __func__, hw_irq);
+	wsp_mask_real_irq(hw_irq, wsp_ics);
+}
+
+static long wsp_ics_get_server(struct ics *ics, unsigned long hw_irq)
+{
+	struct wsp_ics *wsp_ics = to_wsp_ics(ics);
+
+	if (!wsp_ics_match_hwirq(wsp_ics, hw_irq))
+		return -ENOENT;
+
+	return get_irq_server(wsp_ics, hw_irq);
+}
+
+/* HW Number allocation API */
+
+static struct wsp_ics *wsp_ics_find_dn_ics(struct device_node *dn)
+{
+	struct device_node *iparent;
+	int i;
+
+	iparent = of_irq_find_parent(dn);
+	if (!iparent) {
+		pr_err("wsp_ics: Failed to find interrupt parent!\n");
+		return NULL;
+	}
+
+	for(i = 0; i < num_ics; i++) {
+		if(ics_list[i].dn == iparent)
+			break;
+	}
+
+	if (i >= num_ics) {
+		pr_err("wsp_ics: Unable to find parent bitmap!\n");
+		return NULL;
+	}
+
+	return &ics_list[i];
+}
+
+int wsp_ics_alloc_irq(struct device_node *dn, int num)
+{
+	struct wsp_ics *ics;
+	int order, offset;
+
+	ics = wsp_ics_find_dn_ics(dn);
+	if (!ics)
+		return -ENODEV;
+
+	/* Fast, but overly strict if num isn't a power of two */
+	order = get_count_order(num);
+
+	spin_lock_irq(&ics->lock);
+	offset = bitmap_find_free_region(ics->bitmap, ics->count, order);
+	spin_unlock_irq(&ics->lock);
+
+	if (offset < 0)
+		return offset;
+
+	return offset + ics->hwirq_start;
+}
+
+void wsp_ics_free_irq(struct device_node *dn, unsigned int irq)
+{
+	struct wsp_ics *ics;
+
+	ics = wsp_ics_find_dn_ics(dn);
+	if (WARN_ON(!ics))
+		return;
+
+	spin_lock_irq(&ics->lock);
+	bitmap_release_region(ics->bitmap, irq, 0);
+	spin_unlock_irq(&ics->lock);
+}
+
+/* Initialisation */
+
+static int __init wsp_ics_bitmap_setup(struct wsp_ics *ics,
+				      struct device_node *dn)
+{
+	int len, i, j, size;
+	u32 start, count;
+	const u32 *p;
+
+	size = BITS_TO_LONGS(ics->count) * sizeof(long);
+	ics->bitmap = kzalloc(size, GFP_KERNEL);
+	if (!ics->bitmap) {
+		pr_err("wsp_ics: ENOMEM allocating IRQ bitmap!\n");
+		return -ENOMEM;
+	}
+
+	spin_lock_init(&ics->lock);
+
+	p = of_get_property(dn, "available-ranges", &len);
+	if (!p || !len) {
+		/* FIXME this should be a WARN() once mambo is updated */
+		pr_err("wsp_ics: No available-ranges defined for %s\n",
+			dn->full_name);
+		return 0;
+	}
+
+	if (len % (2 * sizeof(u32)) != 0) {
+		/* FIXME this should be a WARN() once mambo is updated */
+		pr_err("wsp_ics: Invalid available-ranges for %s\n",
+			dn->full_name);
+		return 0;
+	}
+
+	bitmap_fill(ics->bitmap, ics->count);
+
+	for (i = 0; i < len / sizeof(u32); i += 2) {
+		start = of_read_number(p + i, 1);
+		count = of_read_number(p + i + 1, 1);
+
+		pr_devel("%s: start: %d count: %d\n", __func__, start, count);
+
+		if ((start + count) > (ics->hwirq_start + ics->count) ||
+		     start < ics->hwirq_start) {
+			pr_err("wsp_ics: Invalid range! -> %d to %d\n",
+					start, start + count);
+			break;
+		}
+
+		for (j = 0; j < count; j++)
+			bitmap_release_region(ics->bitmap,
+				(start + j) - ics->hwirq_start, 0);
+	}
+
+	/* Ensure LSIs are not available for allocation */
+	bitmap_allocate_region(ics->bitmap, ics->lsi_base,
+			       get_count_order(ics->lsi_count));
+
+	return 0;
+}
+
+static int __init wsp_ics_setup(struct wsp_ics *ics, struct device_node *dn)
+{
+	u32 lsi_buid, msi_buid, msi_base, msi_count;
+	void __iomem *regs;
+	const u32 *p;
+	int rc, len, i;
+	u64 caps, buid;
+
+	p = of_get_property(dn, "interrupt-ranges", &len);
+	if (!p || len < (2 * sizeof(u32))) {
+		pr_err("wsp_ics: No/bad interrupt-ranges found on %s\n",
+			dn->full_name);
+		return -ENOENT;
+	}
+
+	if (len > (2 * sizeof(u32))) {
+		pr_err("wsp_ics: Multiple ics ranges not supported.\n");
+		return -EINVAL;
+	}
+
+	regs = of_iomap(dn, 0);
+	if (!regs) {
+		pr_err("wsp_ics: of_iomap(%s) failed\n", dn->full_name);
+		return -ENXIO;
+	}
+
+	ics->hwirq_start = of_read_number(p, 1);
+	ics->count = of_read_number(p + 1, 1);
+	ics->regs = regs;
+
+	ics->chip_id = wsp_get_chip_id(dn);
+	if (WARN_ON(ics->chip_id < 0))
+		ics->chip_id = 0;
+
+	/* Get some informations about the critter */
+	caps = in_be64(ICS_INT_CAPS_REG(ics->regs));
+	buid = in_be64(INT_SRC_LAYER_BUID_REG(ics->regs));
+	ics->lsi_count = caps >> 56;
+	msi_count = (caps >> 44) & 0x7ff;
+
+	/* Note: LSI BUID is 9 bits, but really only 3 are BUID and the
+	 * rest is mixed in the interrupt number. We store the whole
+	 * thing though
+	 */
+	lsi_buid = (buid >> 48) & 0x1ff;
+	ics->lsi_base = (ics->chip_id << WSP_ICS_CHIP_SHIFT) | lsi_buid << 5;
+	msi_buid = (buid >> 37) & 0x7;
+	msi_base = (ics->chip_id << WSP_ICS_CHIP_SHIFT) | msi_buid << 11;
+
+	pr_info("wsp_ics: Found %s\n", dn->full_name);
+	pr_info("wsp_ics:    irq range : 0x%06llx..0x%06llx\n",
+		ics->hwirq_start, ics->hwirq_start + ics->count - 1);
+	pr_info("wsp_ics:    %4d LSIs : 0x%06x..0x%06x\n",
+		ics->lsi_count, ics->lsi_base,
+		ics->lsi_base + ics->lsi_count - 1);
+	pr_info("wsp_ics:    %4d MSIs : 0x%06x..0x%06x\n",
+		msi_count, msi_base,
+		msi_base + msi_count - 1);
+
+	/* Let's check the HW config is sane */
+	if (ics->lsi_base < ics->hwirq_start ||
+	    (ics->lsi_base + ics->lsi_count) > (ics->hwirq_start + ics->count))
+		pr_warning("wsp_ics: WARNING ! LSIs out of interrupt-ranges !\n");
+	if (msi_base < ics->hwirq_start ||
+	    (msi_base + msi_count) > (ics->hwirq_start + ics->count))
+		pr_warning("wsp_ics: WARNING ! MSIs out of interrupt-ranges !\n");
+
+	/* We don't check for overlap between LSI and MSI, which will happen
+	 * if we use the same BUID, I'm not sure yet how legit that is.
+	 */
+
+	rc = wsp_ics_bitmap_setup(ics, dn);
+	if (rc) {
+		iounmap(regs);
+		return rc;
+	}
+
+	ics->dn = of_node_get(dn);
+	alloc_irq_map(ics);
+
+	for(i = 0; i < ics->count; i++)
+		wsp_mask_real_irq(ics->hwirq_start + i, ics);
+
+	ics->ics.map = wsp_ics_map;
+	ics->ics.mask_unknown = wsp_ics_mask_unknown;
+	ics->ics.get_server = wsp_ics_get_server;
+	ics->ics.host_match = wsp_ics_host_match;
+
+	xics_register_ics(&ics->ics);
+
+	return 0;
+}
+
+static void __init wsp_ics_set_default_server(void)
+{
+	struct device_node *np;
+	u32 hwid;
+
+	/* Find the server number for the boot cpu. */
+	np = of_get_cpu_node(boot_cpuid, NULL);
+	BUG_ON(!np);
+
+	hwid = get_hard_smp_processor_id(boot_cpuid);
+
+	pr_info("wsp_ics: default server is %#x, CPU %s\n", hwid, np->full_name);
+	xics_default_server = hwid;
+
+	of_node_put(np);
+}
+
+static int __init wsp_ics_init(void)
+{
+	struct device_node *dn;
+	struct wsp_ics *ics;
+	int rc, found;
+
+	wsp_ics_set_default_server();
+
+	found = 0;
+	for_each_compatible_node(dn, NULL, "ibm,ppc-xics")
+		found++;
+
+	if (found == 0) {
+		pr_err("wsp_ics: No ICS's found!\n");
+		return -ENODEV;
+	}
+
+	ics_list = kmalloc(sizeof(*ics) * found, GFP_KERNEL);
+	if (!ics_list) {
+		pr_err("wsp_ics: No memory for structs.\n");
+		return -ENOMEM;
+	}
+
+	num_ics = 0;
+	ics = ics_list;
+	for_each_compatible_node(dn, NULL, "ibm,wsp-xics") {
+		rc = wsp_ics_setup(ics, dn);
+		if (rc == 0) {
+			ics++;
+			num_ics++;
+		}
+	}
+
+	if (found != num_ics) {
+		pr_err("wsp_ics: Failed setting up %d ICS's\n",
+			found - num_ics);
+		return -1;
+	}
+
+	return 0;
+}
+
+void __init wsp_init_irq(void)
+{
+	wsp_ics_init();
+	xics_init();
+
+	/* We need to patch our irq chip's EOI to point to the right ICP */
+	wsp_irq_chip.irq_eoi = icp_ops->eoi;
+}