9 files changed, 390 insertions, 104 deletions

diff --git a/arch/powerpc/sysdev/xics/Kconfig b/arch/powerpc/sysdev/xics/Kconfig
index 304614c920aa..063d9195891f 100644
--- a/arch/powerpc/sysdev/xics/Kconfig
+++ b/arch/powerpc/sysdev/xics/Kconfig
@@ -12,3 +12,6 @@ config PPC_ICP_HV
 
 config PPC_ICS_RTAS
 	def_bool n
+
+config PPC_ICS_NATIVE
+	def_bool n
diff --git a/arch/powerpc/sysdev/xics/Makefile b/arch/powerpc/sysdev/xics/Makefile
index ba1e3117b1c0..747063927c6c 100644
--- a/arch/powerpc/sysdev/xics/Makefile
+++ b/arch/powerpc/sysdev/xics/Makefile
@@ -4,4 +4,5 @@ obj-y				+= xics-common.o
 obj-$(CONFIG_PPC_ICP_NATIVE)	+= icp-native.o
 obj-$(CONFIG_PPC_ICP_HV)	+= icp-hv.o
 obj-$(CONFIG_PPC_ICS_RTAS)	+= ics-rtas.o
+obj-$(CONFIG_PPC_ICS_NATIVE)	+= ics-native.o
 obj-$(CONFIG_PPC_POWERNV)	+= ics-opal.o icp-opal.o
diff --git a/arch/powerpc/sysdev/xics/icp-hv.c b/arch/powerpc/sysdev/xics/icp-hv.c
index ad8117148ea3..cf8db19a4f7d 100644
--- a/arch/powerpc/sysdev/xics/icp-hv.c
+++ b/arch/powerpc/sysdev/xics/icp-hv.c
@@ -7,6 +7,7 @@
 #include <linux/irq.h>
 #include <linux/smp.h>
 #include <linux/interrupt.h>
+#include <linux/irqdomain.h>
 #include <linux/cpu.h>
 #include <linux/of.h>
 
@@ -161,7 +162,7 @@ static const struct icp_ops icp_hv_ops = {
 #endif
 };
 
-int icp_hv_init(void)
+int __init icp_hv_init(void)
 {
 	struct device_node *np;
 
@@ -174,6 +175,7 @@ int icp_hv_init(void)
 
 	icp_ops = &icp_hv_ops;
 
+	of_node_put(np);
 	return 0;
 }
 
diff --git a/arch/powerpc/sysdev/xics/icp-native.c b/arch/powerpc/sysdev/xics/icp-native.c
index 7d13d2ef5a90..edc17b6b1cc2 100644
--- a/arch/powerpc/sysdev/xics/icp-native.c
+++ b/arch/powerpc/sysdev/xics/icp-native.c
@@ -6,15 +6,16 @@
 #include <linux/types.h>
 #include <linux/kernel.h>
 #include <linux/irq.h>
+#include <linux/irqdomain.h>
 #include <linux/smp.h>
 #include <linux/interrupt.h>
 #include <linux/init.h>
 #include <linux/cpu.h>
 #include <linux/of.h>
+#include <linux/of_address.h>
 #include <linux/spinlock.h>
 #include <linux/module.h>
 
-#include <asm/prom.h>
 #include <asm/io.h>
 #include <asm/smp.h>
 #include <asm/irq.h>
diff --git a/arch/powerpc/sysdev/xics/icp-opal.c b/arch/powerpc/sysdev/xics/icp-opal.c
index 68fd2540b093..4dae624b9f2f 100644
--- a/arch/powerpc/sysdev/xics/icp-opal.c
+++ b/arch/powerpc/sysdev/xics/icp-opal.c
@@ -7,6 +7,7 @@
 #include <linux/irq.h>
 #include <linux/smp.h>
 #include <linux/interrupt.h>
+#include <linux/irqdomain.h>
 #include <linux/cpu.h>
 #include <linux/of.h>
 
@@ -183,7 +184,7 @@ static const struct icp_ops icp_opal_ops = {
 #endif
 };
 
-int icp_opal_init(void)
+int __init icp_opal_init(void)
 {
 	struct device_node *np;
 
@@ -195,6 +196,7 @@ int icp_opal_init(void)
 
 	printk("XICS: Using OPAL ICP fallbacks\n");
 
+	of_node_put(np);
 	return 0;
 }
 
diff --git a/arch/powerpc/sysdev/xics/ics-native.c b/arch/powerpc/sysdev/xics/ics-native.c
new file mode 100644
index 000000000000..112c8a1e8159
--- /dev/null
+++ b/arch/powerpc/sysdev/xics/ics-native.c
@@ -0,0 +1,254 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * ICS backend for OPAL managed interrupts.
+ *
+ * Copyright 2011 IBM Corp.
+ */
+
+//#define DEBUG
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/irq.h>
+#include <linux/smp.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/cpu.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/spinlock.h>
+#include <linux/msi.h>
+#include <linux/list.h>
+
+#include <asm/smp.h>
+#include <asm/machdep.h>
+#include <asm/irq.h>
+#include <asm/errno.h>
+#include <asm/xics.h>
+#include <asm/opal.h>
+#include <asm/firmware.h>
+
+struct ics_native {
+	struct ics		ics;
+	struct device_node	*node;
+	void __iomem    	*base;
+	u32             	ibase;
+	u32             	icount;
+};
+#define to_ics_native(_ics)     container_of(_ics, struct ics_native, ics)
+
+static void __iomem *ics_native_xive(struct ics_native *in, unsigned int vec)
+{
+	return in->base + 0x800 + ((vec - in->ibase) << 2);
+}
+
+static void ics_native_unmask_irq(struct irq_data *d)
+{
+	unsigned int vec = (unsigned int)irqd_to_hwirq(d);
+	struct ics *ics = irq_data_get_irq_chip_data(d);
+	struct ics_native *in = to_ics_native(ics);
+	unsigned int server;
+
+	pr_devel("ics-native: unmask virq %d [hw 0x%x]\n", d->irq, vec);
+
+	if (vec < in->ibase || vec >= (in->ibase + in->icount))
+		return;
+
+	server = xics_get_irq_server(d->irq, irq_data_get_affinity_mask(d), 0);
+	out_be32(ics_native_xive(in, vec), (server << 8) | DEFAULT_PRIORITY);
+}
+
+static unsigned int ics_native_startup(struct irq_data *d)
+{
+#ifdef CONFIG_PCI_MSI
+	/*
+	 * The generic MSI code returns with the interrupt disabled on the
+	 * card, using the MSI mask bits. Firmware doesn't appear to unmask
+	 * at that level, so we do it here by hand.
+	 */
+	if (irq_data_get_msi_desc(d))
+		pci_msi_unmask_irq(d);
+#endif
+
+	/* unmask it */
+	ics_native_unmask_irq(d);
+	return 0;
+}
+
+static void ics_native_do_mask(struct ics_native *in, unsigned int vec)
+{
+	out_be32(ics_native_xive(in, vec), 0xff);
+}
+
+static void ics_native_mask_irq(struct irq_data *d)
+{
+	unsigned int vec = (unsigned int)irqd_to_hwirq(d);
+	struct ics *ics = irq_data_get_irq_chip_data(d);
+	struct ics_native *in = to_ics_native(ics);
+
+	pr_devel("ics-native: mask virq %d [hw 0x%x]\n", d->irq, vec);
+
+	if (vec < in->ibase || vec >= (in->ibase + in->icount))
+		return;
+	ics_native_do_mask(in, vec);
+}
+
+static int ics_native_set_affinity(struct irq_data *d,
+				   const struct cpumask *cpumask,
+				   bool force)
+{
+	unsigned int vec = (unsigned int)irqd_to_hwirq(d);
+	struct ics *ics = irq_data_get_irq_chip_data(d);
+	struct ics_native *in = to_ics_native(ics);
+	int server;
+	u32 xive;
+
+	if (vec < in->ibase || vec >= (in->ibase + in->icount))
+		return -EINVAL;
+
+	server = xics_get_irq_server(d->irq, cpumask, 1);
+	if (server == -1) {
+		pr_warn("%s: No online cpus in the mask %*pb for irq %d\n",
+			__func__, cpumask_pr_args(cpumask), d->irq);
+		return -1;
+	}
+
+	xive = in_be32(ics_native_xive(in, vec));
+	xive = (xive & 0xff) | (server << 8);
+	out_be32(ics_native_xive(in, vec), xive);
+
+	return IRQ_SET_MASK_OK;
+}
+
+static struct irq_chip ics_native_irq_chip = {
+	.name = "ICS",
+	.irq_startup		= ics_native_startup,
+	.irq_mask		= ics_native_mask_irq,
+	.irq_unmask		= ics_native_unmask_irq,
+	.irq_eoi		= NULL, /* Patched at init time */
+	.irq_set_affinity 	= ics_native_set_affinity,
+	.irq_set_type		= xics_set_irq_type,
+	.irq_retrigger		= xics_retrigger,
+};
+
+static int ics_native_check(struct ics *ics, unsigned int hw_irq)
+{
+	struct ics_native *in = to_ics_native(ics);
+
+	pr_devel("%s: hw_irq=0x%x\n", __func__, hw_irq);
+
+	if (hw_irq < in->ibase || hw_irq >= (in->ibase + in->icount))
+		return -EINVAL;
+
+	return 0;
+}
+
+static void ics_native_mask_unknown(struct ics *ics, unsigned long vec)
+{
+	struct ics_native *in = to_ics_native(ics);
+
+	if (vec < in->ibase || vec >= (in->ibase + in->icount))
+		return;
+
+	ics_native_do_mask(in, vec);
+}
+
+static long ics_native_get_server(struct ics *ics, unsigned long vec)
+{
+	struct ics_native *in = to_ics_native(ics);
+	u32 xive;
+
+	if (vec < in->ibase || vec >= (in->ibase + in->icount))
+		return -EINVAL;
+
+	xive = in_be32(ics_native_xive(in, vec));
+	return (xive >> 8) & 0xfff;
+}
+
+static int ics_native_host_match(struct ics *ics, struct device_node *node)
+{
+	struct ics_native *in = to_ics_native(ics);
+
+	return in->node == node;
+}
+
+static struct ics ics_native_template = {
+	.check		= ics_native_check,
+	.mask_unknown	= ics_native_mask_unknown,
+	.get_server	= ics_native_get_server,
+	.host_match	= ics_native_host_match,
+	.chip = &ics_native_irq_chip,
+};
+
+static int __init ics_native_add_one(struct device_node *np)
+{
+	struct ics_native *ics;
+	u32 ranges[2];
+	int rc, count;
+
+	ics = kzalloc(sizeof(struct ics_native), GFP_KERNEL);
+	if (!ics)
+		return -ENOMEM;
+	ics->node = of_node_get(np);
+	memcpy(&ics->ics, &ics_native_template, sizeof(struct ics));
+
+	ics->base = of_iomap(np, 0);
+	if (!ics->base) {
+		pr_err("Failed to map %pOFP\n", np);
+		rc = -ENOMEM;
+		goto fail;
+	}
+
+	count = of_property_count_u32_elems(np, "interrupt-ranges");
+	if (count < 2 || count & 1) {
+		pr_err("Failed to read interrupt-ranges of %pOFP\n", np);
+		rc = -EINVAL;
+		goto fail;
+	}
+	if (count > 2) {
+		pr_warn("ICS %pOFP has %d ranges, only one supported\n",
+			np, count >> 1);
+	}
+	rc = of_property_read_u32_array(np, "interrupt-ranges",
+					ranges, 2);
+	if (rc) {
+		pr_err("Failed to read interrupt-ranges of %pOFP\n", np);
+		goto fail;
+	}
+	ics->ibase = ranges[0];
+	ics->icount = ranges[1];
+
+	pr_info("ICS native initialized for sources %d..%d\n",
+		ics->ibase, ics->ibase + ics->icount - 1);
+
+	/* Register ourselves */
+	xics_register_ics(&ics->ics);
+
+	return 0;
+fail:
+	of_node_put(ics->node);
+	kfree(ics);
+	return rc;
+}
+
+int __init ics_native_init(void)
+{
+	struct device_node *ics;
+	bool found_one = false;
+
+	/* We need to patch our irq chip's EOI to point to the
+	 * right ICP
+	 */
+	ics_native_irq_chip.irq_eoi = icp_ops->eoi;
+
+	/* Find native ICS in the device-tree */
+	for_each_compatible_node(ics, NULL, "openpower,xics-sources") {
+		if (ics_native_add_one(ics) == 0)
+			found_one = true;
+	}
+
+	if (found_one)
+		pr_info("ICS native backend registered\n");
+
+	return found_one ? 0 : -ENODEV;
+}
diff --git a/arch/powerpc/sysdev/xics/ics-opal.c b/arch/powerpc/sysdev/xics/ics-opal.c
index 823f6c9664cd..6cfbb4fac7fb 100644
--- a/arch/powerpc/sysdev/xics/ics-opal.c
+++ b/arch/powerpc/sysdev/xics/ics-opal.c
@@ -18,7 +18,6 @@
 #include <linux/spinlock.h>
 #include <linux/msi.h>
 
-#include <asm/prom.h>
 #include <asm/smp.h>
 #include <asm/machdep.h>
 #include <asm/irq.h>
@@ -62,17 +61,6 @@ static void ics_opal_unmask_irq(struct irq_data *d)
 
 static unsigned int ics_opal_startup(struct irq_data *d)
 {
-#ifdef CONFIG_PCI_MSI
-	/*
-	 * The generic MSI code returns with the interrupt disabled on the
-	 * card, using the MSI mask bits. Firmware doesn't appear to unmask
-	 * at that level, so we do it here by hand.
-	 */
-	if (irq_data_get_msi_desc(d))
-		pci_msi_unmask_irq(d);
-#endif
-
-	/* unmask it */
 	ics_opal_unmask_irq(d);
 	return 0;
 }
@@ -133,7 +121,7 @@ static int ics_opal_set_affinity(struct irq_data *d,
 	}
 	server = ics_opal_mangle_server(wanted_server);
 
-	pr_devel("ics-hal: set-affinity irq %d [hw 0x%x] server: 0x%x/0x%x\n",
+	pr_debug("ics-hal: set-affinity irq %d [hw 0x%x] server: 0x%x/0x%x\n",
 		 d->irq, hw_irq, wanted_server, server);
 
 	rc = opal_set_xive(hw_irq, server, priority);
@@ -157,26 +145,13 @@ static struct irq_chip ics_opal_irq_chip = {
 	.irq_retrigger = xics_retrigger,
 };
 
-static int ics_opal_map(struct ics *ics, unsigned int virq);
-static void ics_opal_mask_unknown(struct ics *ics, unsigned long vec);
-static long ics_opal_get_server(struct ics *ics, unsigned long vec);
-
 static int ics_opal_host_match(struct ics *ics, struct device_node *node)
 {
 	return 1;
 }
 
-/* Only one global & state struct ics */
-static struct ics ics_hal = {
-	.map		= ics_opal_map,
-	.mask_unknown	= ics_opal_mask_unknown,
-	.get_server	= ics_opal_get_server,
-	.host_match	= ics_opal_host_match,
-};
-
-static int ics_opal_map(struct ics *ics, unsigned int virq)
+static int ics_opal_check(struct ics *ics, unsigned int hw_irq)
 {
-	unsigned int hw_irq = (unsigned int)virq_to_hw(virq);
 	int64_t rc;
 	__be16 server;
 	int8_t priority;
@@ -189,9 +164,6 @@ static int ics_opal_map(struct ics *ics, unsigned int virq)
 	if (rc != OPAL_SUCCESS)
 		return -ENXIO;
 
-	irq_set_chip_and_handler(virq, &ics_opal_irq_chip, handle_fasteoi_irq);
-	irq_set_chip_data(virq, &ics_hal);
-
 	return 0;
 }
 
@@ -222,6 +194,15 @@ static long ics_opal_get_server(struct ics *ics, unsigned long vec)
 	return ics_opal_unmangle_server(be16_to_cpu(server));
 }
 
+/* Only one global & state struct ics */
+static struct ics ics_hal = {
+	.check		= ics_opal_check,
+	.mask_unknown	= ics_opal_mask_unknown,
+	.get_server	= ics_opal_get_server,
+	.host_match	= ics_opal_host_match,
+	.chip		= &ics_opal_irq_chip,
+};
+
 int __init ics_opal_init(void)
 {
 	if (!firmware_has_feature(FW_FEATURE_OPAL))
diff --git a/arch/powerpc/sysdev/xics/ics-rtas.c b/arch/powerpc/sysdev/xics/ics-rtas.c
index 6aabc74688a6..f8320f8e5bc7 100644
--- a/arch/powerpc/sysdev/xics/ics-rtas.c
+++ b/arch/powerpc/sysdev/xics/ics-rtas.c
@@ -10,7 +10,6 @@
 #include <linux/spinlock.h>
 #include <linux/msi.h>
 
-#include <asm/prom.h>
 #include <asm/smp.h>
 #include <asm/machdep.h>
 #include <asm/irq.h>
@@ -24,19 +23,6 @@ static int ibm_set_xive;
 static int ibm_int_on;
 static int ibm_int_off;
 
-static int ics_rtas_map(struct ics *ics, unsigned int virq);
-static void ics_rtas_mask_unknown(struct ics *ics, unsigned long vec);
-static long ics_rtas_get_server(struct ics *ics, unsigned long vec);
-static int ics_rtas_host_match(struct ics *ics, struct device_node *node);
-
-/* Only one global & state struct ics */
-static struct ics ics_rtas = {
-	.map		= ics_rtas_map,
-	.mask_unknown	= ics_rtas_mask_unknown,
-	.get_server	= ics_rtas_get_server,
-	.host_match	= ics_rtas_host_match,
-};
-
 static void ics_rtas_unmask_irq(struct irq_data *d)
 {
 	unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
@@ -70,15 +56,6 @@ static void ics_rtas_unmask_irq(struct irq_data *d)
 
 static unsigned int ics_rtas_startup(struct irq_data *d)
 {
-#ifdef CONFIG_PCI_MSI
-	/*
-	 * The generic MSI code returns with the interrupt disabled on the
-	 * card, using the MSI mask bits. Firmware doesn't appear to unmask
-	 * at that level, so we do it here by hand.
-	 */
-	if (irq_data_get_msi_desc(d))
-		pci_msi_unmask_irq(d);
-#endif
 	/* unmask it */
 	ics_rtas_unmask_irq(d);
 	return 0;
@@ -146,6 +123,9 @@ static int ics_rtas_set_affinity(struct irq_data *d,
 		return -1;
 	}
 
+	pr_debug("%s: irq %d [hw 0x%x] server: 0x%x\n", __func__, d->irq,
+		 hw_irq, irq_server);
+
 	status = rtas_call(ibm_set_xive, 3, 1, NULL,
 			   hw_irq, irq_server, xics_status[1]);
 
@@ -169,9 +149,8 @@ static struct irq_chip ics_rtas_irq_chip = {
 	.irq_retrigger = xics_retrigger,
 };
 
-static int ics_rtas_map(struct ics *ics, unsigned int virq)
+static int ics_rtas_check(struct ics *ics, unsigned int hw_irq)
 {
-	unsigned int hw_irq = (unsigned int)virq_to_hw(virq);
 	int status[2];
 	int rc;
 
@@ -183,9 +162,6 @@ static int ics_rtas_map(struct ics *ics, unsigned int virq)
 	if (rc)
 		return -ENXIO;
 
-	irq_set_chip_and_handler(virq, &ics_rtas_irq_chip, handle_fasteoi_irq);
-	irq_set_chip_data(virq, &ics_rtas);
-
 	return 0;
 }
 
@@ -213,6 +189,15 @@ static int ics_rtas_host_match(struct ics *ics, struct device_node *node)
 	return !of_device_is_compatible(node, "chrp,iic");
 }
 
+/* Only one global & state struct ics */
+static struct ics ics_rtas = {
+	.check		= ics_rtas_check,
+	.mask_unknown	= ics_rtas_mask_unknown,
+	.get_server	= ics_rtas_get_server,
+	.host_match	= ics_rtas_host_match,
+	.chip = &ics_rtas_irq_chip,
+};
+
 __init int ics_rtas_init(void)
 {
 	ibm_get_xive = rtas_token("ibm,get-xive");
diff --git a/arch/powerpc/sysdev/xics/xics-common.c b/arch/powerpc/sysdev/xics/xics-common.c
index 7e4305c01bac..d3a4156e8788 100644
--- a/arch/powerpc/sysdev/xics/xics-common.c
+++ b/arch/powerpc/sysdev/xics/xics-common.c
@@ -6,6 +6,7 @@
 #include <linux/threads.h>
 #include <linux/kernel.h>
 #include <linux/irq.h>
+#include <linux/irqdomain.h>
 #include <linux/debugfs.h>
 #include <linux/smp.h>
 #include <linux/interrupt.h>
@@ -17,7 +18,6 @@
 #include <linux/spinlock.h>
 #include <linux/delay.h>
 
-#include <asm/prom.h>
 #include <asm/io.h>
 #include <asm/smp.h>
 #include <asm/machdep.h>
@@ -38,7 +38,7 @@ DEFINE_PER_CPU(struct xics_cppr, xics_cppr);
 
 struct irq_domain *xics_host;
 
-static LIST_HEAD(ics_list);
+static struct ics *xics_ics;
 
 void xics_update_irq_servers(void)
 {
@@ -111,18 +111,17 @@ void xics_setup_cpu(void)
 
 void xics_mask_unknown_vec(unsigned int vec)
 {
-	struct ics *ics;
-
 	pr_err("Interrupt 0x%x (real) is invalid, disabling it.\n", vec);
 
-	list_for_each_entry(ics, &ics_list, link)
-		ics->mask_unknown(ics, vec);
+	if (WARN_ON(!xics_ics))
+		return;
+	xics_ics->mask_unknown(xics_ics, vec);
 }
 
 
 #ifdef CONFIG_SMP
 
-static void xics_request_ipi(void)
+static void __init xics_request_ipi(void)
 {
 	unsigned int ipi;
 
@@ -133,7 +132,7 @@ static void xics_request_ipi(void)
 	 * IPIs are marked IRQF_PERCPU. The handler was set in map.
 	 */
 	BUG_ON(request_irq(ipi, icp_ops->ipi_action,
-			   IRQF_PERCPU | IRQF_NO_THREAD, "IPI", NULL));
+			   IRQF_NO_DEBUG | IRQF_PERCPU | IRQF_NO_THREAD, "IPI", NULL));
 }
 
 void __init xics_smp_probe(void)
@@ -147,7 +146,7 @@ void __init xics_smp_probe(void)
 
 #endif /* CONFIG_SMP */
 
-void xics_teardown_cpu(void)
+noinstr void xics_teardown_cpu(void)
 {
 	struct xics_cppr *os_cppr = this_cpu_ptr(&xics_cppr);
 
@@ -160,7 +159,7 @@ void xics_teardown_cpu(void)
 	icp_ops->teardown_cpu();
 }
 
-void xics_kexec_teardown_cpu(int secondary)
+noinstr void xics_kexec_teardown_cpu(int secondary)
 {
 	xics_teardown_cpu();
 
@@ -184,6 +183,8 @@ void xics_migrate_irqs_away(void)
 	unsigned int irq, virq;
 	struct irq_desc *desc;
 
+	pr_debug("%s: CPU %u\n", __func__, cpu);
+
 	/* If we used to be the default server, move to the new "boot_cpuid" */
 	if (hw_cpu == xics_default_server)
 		xics_update_irq_servers();
@@ -198,17 +199,19 @@ void xics_migrate_irqs_away(void)
 		struct irq_chip *chip;
 		long server;
 		unsigned long flags;
-		struct ics *ics;
+		struct irq_data *irqd;
 
 		/* We can't set affinity on ISA interrupts */
-		if (virq < NUM_ISA_INTERRUPTS)
+		if (virq < NR_IRQS_LEGACY)
 			continue;
 		/* We only need to migrate enabled IRQS */
 		if (!desc->action)
 			continue;
-		if (desc->irq_data.domain != xics_host)
+		/* We need a mapping in the XICS IRQ domain */
+		irqd = irq_domain_get_irq_data(xics_host, virq);
+		if (!irqd)
 			continue;
-		irq = desc->irq_data.hwirq;
+		irq = irqd_to_hwirq(irqd);
 		/* We need to get IPIs still. */
 		if (irq == XICS_IPI || irq == XICS_IRQ_SPURIOUS)
 			continue;
@@ -219,13 +222,10 @@ void xics_migrate_irqs_away(void)
 		raw_spin_lock_irqsave(&desc->lock, flags);
 
 		/* Locate interrupt server */
-		server = -1;
-		ics = irq_desc_get_chip_data(desc);
-		if (ics)
-			server = ics->get_server(ics, irq);
+		server = xics_ics->get_server(xics_ics, irq);
 		if (server < 0) {
-			printk(KERN_ERR "%s: Can't find server for irq %d\n",
-			       __func__, irq);
+			pr_err("%s: Can't find server for irq %d/%x\n",
+			       __func__, virq, irq);
 			goto unlock;
 		}
 
@@ -307,13 +307,9 @@ int xics_get_irq_server(unsigned int virq, const struct cpumask *cpumask,
 static int xics_host_match(struct irq_domain *h, struct device_node *node,
 			   enum irq_domain_bus_token bus_token)
 {
-	struct ics *ics;
-
-	list_for_each_entry(ics, &ics_list, link)
-		if (ics->host_match(ics, node))
-			return 1;
-
-	return 0;
+	if (WARN_ON(!xics_ics))
+		return 0;
+	return xics_ics->host_match(xics_ics, node) ? 1 : 0;
 }
 
 /* Dummies */
@@ -327,12 +323,10 @@ static struct irq_chip xics_ipi_chip = {
 	.irq_unmask = xics_ipi_unmask,
 };
 
-static int xics_host_map(struct irq_domain *h, unsigned int virq,
-			 irq_hw_number_t hw)
+static int xics_host_map(struct irq_domain *domain, unsigned int virq,
+			 irq_hw_number_t hwirq)
 {
-	struct ics *ics;
-
-	pr_devel("xics: map virq %d, hwirq 0x%lx\n", virq, hw);
+	pr_devel("xics: map virq %d, hwirq 0x%lx\n", virq, hwirq);
 
 	/*
 	 * Mark interrupts as edge sensitive by default so that resend
@@ -342,18 +336,23 @@ static int xics_host_map(struct irq_domain *h, unsigned int virq,
 	irq_clear_status_flags(virq, IRQ_LEVEL);
 
 	/* Don't call into ICS for IPIs */
-	if (hw == XICS_IPI) {
+	if (hwirq == XICS_IPI) {
 		irq_set_chip_and_handler(virq, &xics_ipi_chip,
 					 handle_percpu_irq);
 		return 0;
 	}
 
-	/* Let the ICS setup the chip data */
-	list_for_each_entry(ics, &ics_list, link)
-		if (ics->map(ics, virq) == 0)
-			return 0;
+	if (WARN_ON(!xics_ics))
+		return -EINVAL;
 
-	return -EINVAL;
+	if (xics_ics->check(xics_ics, hwirq))
+		return -EINVAL;
+
+	/* Let the ICS be the chip data for the XICS domain. For ICS native */
+	irq_domain_set_info(domain, virq, hwirq, xics_ics->chip,
+			    xics_ics, handle_fasteoi_irq, NULL, NULL);
+
+	return 0;
 }
 
 static int xics_host_xlate(struct irq_domain *h, struct device_node *ct,
@@ -412,22 +411,76 @@ int xics_retrigger(struct irq_data *data)
 	return 0;
 }
 
+#ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
+static int xics_host_domain_translate(struct irq_domain *d, struct irq_fwspec *fwspec,
+				      unsigned long *hwirq, unsigned int *type)
+{
+	return xics_host_xlate(d, to_of_node(fwspec->fwnode), fwspec->param,
+			       fwspec->param_count, hwirq, type);
+}
+
+static int xics_host_domain_alloc(struct irq_domain *domain, unsigned int virq,
+				  unsigned int nr_irqs, void *arg)
+{
+	struct irq_fwspec *fwspec = arg;
+	irq_hw_number_t hwirq;
+	unsigned int type = IRQ_TYPE_NONE;
+	int i, rc;
+
+	rc = xics_host_domain_translate(domain, fwspec, &hwirq, &type);
+	if (rc)
+		return rc;
+
+	pr_debug("%s %d/%lx #%d\n", __func__, virq, hwirq, nr_irqs);
+
+	for (i = 0; i < nr_irqs; i++)
+		irq_domain_set_info(domain, virq + i, hwirq + i, xics_ics->chip,
+				    xics_ics, handle_fasteoi_irq, NULL, NULL);
+
+	return 0;
+}
+
+static void xics_host_domain_free(struct irq_domain *domain,
+				  unsigned int virq, unsigned int nr_irqs)
+{
+	pr_debug("%s %d #%d\n", __func__, virq, nr_irqs);
+}
+#endif
+
 static const struct irq_domain_ops xics_host_ops = {
+#ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
+	.alloc	= xics_host_domain_alloc,
+	.free	= xics_host_domain_free,
+	.translate = xics_host_domain_translate,
+#endif
 	.match = xics_host_match,
 	.map = xics_host_map,
 	.xlate = xics_host_xlate,
 };
 
-static void __init xics_init_host(void)
+static int __init xics_allocate_domain(void)
 {
-	xics_host = irq_domain_add_tree(NULL, &xics_host_ops, NULL);
-	BUG_ON(xics_host == NULL);
+	struct fwnode_handle *fn;
+
+	fn = irq_domain_alloc_named_fwnode("XICS");
+	if (!fn)
+		return -ENOMEM;
+
+	xics_host = irq_domain_create_tree(fn, &xics_host_ops, NULL);
+	if (!xics_host) {
+		irq_domain_free_fwnode(fn);
+		return -ENOMEM;
+	}
+
 	irq_set_default_host(xics_host);
+	return 0;
 }
 
 void __init xics_register_ics(struct ics *ics)
 {
-	list_add(&ics->link, &ics_list);
+	if (WARN_ONCE(xics_ics, "XICS: Source Controller is already defined !"))
+		return;
+	xics_ics = ics;
 }
 
 static void __init xics_get_server_size(void)
@@ -477,11 +530,15 @@ void __init xics_init(void)
 	if (rc < 0)
 		rc = ics_opal_init();
 	if (rc < 0)
+		rc = ics_native_init();
+	if (rc < 0)
 		pr_warn("XICS: Cannot find a Source Controller !\n");
 
 	/* Initialize common bits */
 	xics_get_server_size();
 	xics_update_irq_servers();
-	xics_init_host();
+	rc = xics_allocate_domain();
+	if (rc < 0)
+		pr_err("XICS: Failed to create IRQ domain");
 	xics_setup_cpu();
 }