powerpc/xics: Rewrite XICS driver

This is a significant rework of the XICS driver, too significant to
conveniently break it up into a series of smaller patches to be honest.

The driver is moved to a more generic location to allow new platforms
to use it, and is broken up into separate ICP and ICS "backends". For
now we have the native and "hypervisor" ICP backends and one common
RTAS ICS backend.

The driver supports one ICP backend instanciation, and many ICS ones,
in order to accomodate future platforms with multiple possibly different
interrupt "sources" mechanisms.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

19 files changed, 1377 insertions, 1017 deletions

diff --git a/arch/powerpc/include/asm/irq.h b/arch/powerpc/include/asm/irq.h
index 67ab5fb7d153..47b7905a6369 100644
--- a/arch/powerpc/include/asm/irq.h
+++ b/arch/powerpc/include/asm/irq.h
@@ -142,6 +142,12 @@ extern struct irq_map_entry irq_map[NR_IRQS];
 
 extern irq_hw_number_t virq_to_hw(unsigned int virq);
 
+/* This will eventually -replace- virq_to_hw if/when we stash the
+ * HW number in the irq_data itself. We use a macro so we can inline
+ * it as irq_data isn't defined yet
+ */
+#define irq_data_to_hw(d) (irq_map[(d)->irq].hwirq)
+
 /**
  * irq_alloc_host - Allocate a new irq_host data structure
  * @of_node: optional device-tree node of the interrupt controller
diff --git a/arch/powerpc/include/asm/xics.h b/arch/powerpc/include/asm/xics.h
new file mode 100644
index 000000000000..146aad8534de
--- /dev/null
+++ b/arch/powerpc/include/asm/xics.h
@@ -0,0 +1,139 @@
+/*
+ * Common definitions accross all variants of ICP and ICS interrupt
+ * controllers.
+ */
+
+#ifndef _XICS_H
+#define _XICS_H
+
+#define XICS_IPI		2
+#define XICS_IRQ_SPURIOUS	0
+
+/* Want a priority other than 0.  Various HW issues require this. */
+#define	DEFAULT_PRIORITY	5
+
+/*
+ * Mark IPIs as higher priority so we can take them inside interrupts that
+ * arent marked IRQF_DISABLED
+ */
+#define IPI_PRIORITY		4
+
+/* The least favored priority */
+#define LOWEST_PRIORITY		0xFF
+
+/* The number of priorities defined above */
+#define MAX_NUM_PRIORITIES	3
+
+/* Native ICP */
+extern int icp_native_init(void);
+
+/* PAPR ICP */
+extern int icp_hv_init(void);
+
+/* ICP ops */
+struct icp_ops {
+	unsigned int (*get_irq)(void);
+	void (*eoi)(struct irq_data *d);
+	void (*set_priority)(unsigned char prio);
+	void (*teardown_cpu)(void);
+	void (*flush_ipi)(void);
+#ifdef CONFIG_SMP
+	void (*message_pass)(int target, int msg);
+	irq_handler_t ipi_action;
+#endif
+};
+
+extern const struct icp_ops *icp_ops;
+
+/* Native ICS */
+extern int ics_native_init(void);
+
+/* RTAS ICS */
+extern int ics_rtas_init(void);
+
+/* ICS instance, hooked up to chip_data of an irq */
+struct ics {
+	struct list_head link;
+	int (*map)(struct ics *ics, unsigned int virq);
+	void (*mask_unknown)(struct ics *ics, unsigned long vec);
+	long (*get_server)(struct ics *ics, unsigned long vec);
+	char data[];
+};
+
+/* Commons */
+extern unsigned int xics_default_server;
+extern unsigned int xics_default_distrib_server;
+extern unsigned int xics_interrupt_server_size;
+extern struct irq_host *xics_host;
+
+struct xics_cppr {
+	unsigned char stack[MAX_NUM_PRIORITIES];
+	int index;
+};
+
+DECLARE_PER_CPU(struct xics_cppr, xics_cppr);
+
+static inline void xics_push_cppr(unsigned int vec)
+{
+	struct xics_cppr *os_cppr = &__get_cpu_var(xics_cppr);
+
+	if (WARN_ON(os_cppr->index >= MAX_NUM_PRIORITIES - 1))
+		return;
+
+	if (vec == XICS_IPI)
+		os_cppr->stack[++os_cppr->index] = IPI_PRIORITY;
+	else
+		os_cppr->stack[++os_cppr->index] = DEFAULT_PRIORITY;
+}
+
+static inline unsigned char xics_pop_cppr(void)
+{
+	struct xics_cppr *os_cppr = &__get_cpu_var(xics_cppr);
+
+	if (WARN_ON(os_cppr->index < 1))
+		return LOWEST_PRIORITY;
+
+	return os_cppr->stack[--os_cppr->index];
+}
+
+static inline void xics_set_base_cppr(unsigned char cppr)
+{
+	struct xics_cppr *os_cppr = &__get_cpu_var(xics_cppr);
+
+	/* we only really want to set the priority when there's
+	 * just one cppr value on the stack
+	 */
+	WARN_ON(os_cppr->index != 0);
+
+	os_cppr->stack[0] = cppr;
+}
+
+static inline unsigned char xics_cppr_top(void)
+{
+	struct xics_cppr *os_cppr = &__get_cpu_var(xics_cppr);
+	
+	return os_cppr->stack[os_cppr->index];
+}
+
+DECLARE_PER_CPU_SHARED_ALIGNED(unsigned long, xics_ipi_message);
+
+extern void xics_init(void);
+extern void xics_setup_cpu(void);
+extern void xics_update_irq_servers(void);
+extern void xics_set_cpu_giq(unsigned int gserver, unsigned int join);
+extern void xics_mask_unknown_vec(unsigned int vec);
+extern irqreturn_t xics_ipi_dispatch(int cpu);
+extern int xics_smp_probe(void);
+extern void xics_register_ics(struct ics *ics);
+extern void xics_teardown_cpu(void);
+extern void xics_kexec_teardown_cpu(int secondary);
+extern void xics_migrate_irqs_away(void);
+#ifdef CONFIG_SMP
+extern int xics_get_irq_server(unsigned int virq, const struct cpumask *cpumask,
+			       unsigned int strict_check);
+#else
+#define xics_get_irq_server(virq, cpumask, strict_check) (xics_default_server)
+#endif
+
+
+#endif /* _XICS_H */
diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig
index 5b3da4b4ea79..b0449229836e 100644
--- a/arch/powerpc/platforms/pseries/Kconfig
+++ b/arch/powerpc/platforms/pseries/Kconfig
@@ -3,7 +3,10 @@ config PPC_PSERIES
 	bool "IBM pSeries & new (POWER5-based) iSeries"
 	select MPIC
 	select PCI_MSI
-	select XICS
+	select PPC_XICS
+	select PPC_ICP_NATIVE
+	select PPC_ICP_HV
+	select PPC_ICS_RTAS
 	select PPC_I8259
 	select PPC_RTAS
 	select PPC_RTAS_DAEMON
diff --git a/arch/powerpc/platforms/pseries/Makefile b/arch/powerpc/platforms/pseries/Makefile
index fc5237810ece..4cfefbaccd5f 100644
--- a/arch/powerpc/platforms/pseries/Makefile
+++ b/arch/powerpc/platforms/pseries/Makefile
@@ -5,7 +5,6 @@ obj-y			:= lpar.o hvCall.o nvram.o reconfig.o \
 			   setup.o iommu.o event_sources.o ras.o \
 			   firmware.o power.o dlpar.o mobility.o
 obj-$(CONFIG_SMP)	+= smp.o
-obj-$(CONFIG_XICS)	+= xics.o
 obj-$(CONFIG_SCANLOG)	+= scanlog.o
 obj-$(CONFIG_EEH)	+= eeh.o eeh_cache.o eeh_driver.o eeh_event.o eeh_sysfs.o
 obj-$(CONFIG_KEXEC)	+= kexec.o
diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c
index ef8c45489e20..ae6c27df4dc4 100644
--- a/arch/powerpc/platforms/pseries/hotplug-cpu.c
+++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c
@@ -19,6 +19,7 @@
  */
 
 #include <linux/kernel.h>
+#include <linux/interrupt.h>
 #include <linux/delay.h>
 #include <linux/cpu.h>
 #include <asm/system.h>
@@ -28,7 +29,7 @@
 #include <asm/machdep.h>
 #include <asm/vdso_datapage.h>
 #include <asm/pSeries_reconfig.h>
-#include "xics.h"
+#include <asm/xics.h>
 #include "plpar_wrappers.h"
 #include "offline_states.h"
 
diff --git a/arch/powerpc/platforms/pseries/kexec.c b/arch/powerpc/platforms/pseries/kexec.c
index 77d38a5e2ff9..54cf3a4aa16b 100644
--- a/arch/powerpc/platforms/pseries/kexec.c
+++ b/arch/powerpc/platforms/pseries/kexec.c
@@ -7,15 +7,18 @@
  * 2 of the License, or (at your option) any later version.
  */
 
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+
 #include <asm/machdep.h>
 #include <asm/page.h>
 #include <asm/firmware.h>
 #include <asm/kexec.h>
 #include <asm/mpic.h>
+#include <asm/xics.h>
 #include <asm/smp.h>
 
 #include "pseries.h"
-#include "xics.h"
 #include "plpar_wrappers.h"
 
 static void pseries_kexec_cpu_down(int crash_shutdown, int secondary)
diff --git a/arch/powerpc/platforms/pseries/plpar_wrappers.h b/arch/powerpc/platforms/pseries/plpar_wrappers.h
index d9801117124b..4bf21207d7d3 100644
--- a/arch/powerpc/platforms/pseries/plpar_wrappers.h
+++ b/arch/powerpc/platforms/pseries/plpar_wrappers.h
@@ -270,31 +270,4 @@ static inline long plpar_put_term_char(unsigned long termno, unsigned long len,
 			lbuf[1]);
 }
 
-static inline long plpar_eoi(unsigned long xirr)
-{
-	return plpar_hcall_norets(H_EOI, xirr);
-}
-
-static inline long plpar_cppr(unsigned long cppr)
-{
-	return plpar_hcall_norets(H_CPPR, cppr);
-}
-
-static inline long plpar_ipi(unsigned long servernum, unsigned long mfrr)
-{
-	return plpar_hcall_norets(H_IPI, servernum, mfrr);
-}
-
-static inline long plpar_xirr(unsigned long *xirr_ret, unsigned char cppr)
-{
-	long rc;
-	unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
-
-	rc = plpar_hcall(H_XIRR, retbuf, cppr);
-
-	*xirr_ret = retbuf[0];
-
-	return rc;
-}
-
 #endif /* _PSERIES_PLPAR_WRAPPERS_H */
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 6c42cfde8415..ab73ad2ff59d 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -53,9 +53,9 @@
 #include <asm/irq.h>
 #include <asm/time.h>
 #include <asm/nvram.h>
-#include "xics.h"
 #include <asm/pmc.h>
 #include <asm/mpic.h>
+#include <asm/xics.h>
 #include <asm/ppc-pci.h>
 #include <asm/i8259.h>
 #include <asm/udbg.h>
@@ -205,6 +205,9 @@ static void __init pseries_mpic_init_IRQ(void)
 		mpic_assign_isu(mpic, n, isuaddr);
 	}
 
+	/* Setup top-level get_irq */
+	ppc_md.get_irq = mpic_get_irq;
+
 	/* All ISUs are setup, complete initialization */
 	mpic_init(mpic);
 
@@ -214,7 +217,7 @@ static void __init pseries_mpic_init_IRQ(void)
 
 static void __init pseries_xics_init_IRQ(void)
 {
-	xics_init_IRQ();
+	xics_init();
 	pseries_setup_i8259_cascade();
 }
 
@@ -238,7 +241,6 @@ static void __init pseries_discover_pic(void)
 		if (strstr(typep, "open-pic")) {
 			pSeries_mpic_node = of_node_get(np);
 			ppc_md.init_IRQ       = pseries_mpic_init_IRQ;
-			ppc_md.get_irq        = mpic_get_irq;
 			setup_kexec_cpu_down_mpic();
 			smp_init_pseries_mpic();
 			return;
diff --git a/arch/powerpc/platforms/pseries/smp.c b/arch/powerpc/platforms/pseries/smp.c
index a509c5292a67..fc72bfce7320 100644
--- a/arch/powerpc/platforms/pseries/smp.c
+++ b/arch/powerpc/platforms/pseries/smp.c
@@ -44,10 +44,11 @@
 #include <asm/mpic.h>
 #include <asm/vdso_datapage.h>
 #include <asm/cputhreads.h>
+#include <asm/mpic.h>
+#include <asm/xics.h>
 
 #include "plpar_wrappers.h"
 #include "pseries.h"
-#include "xics.h"
 #include "offline_states.h"
 
 
@@ -136,7 +137,6 @@ out:
 	return 1;
 }
 
-#ifdef CONFIG_XICS
 static void __devinit smp_xics_setup_cpu(int cpu)
 {
 	if (cpu != boot_cpuid)
@@ -151,7 +151,6 @@ static void __devinit smp_xics_setup_cpu(int cpu)
 	set_default_offline_state(cpu);
 #endif
 }
-#endif /* CONFIG_XICS */
 
 static void __devinit smp_pSeries_kick_cpu(int nr)
 {
@@ -197,23 +196,21 @@ static int smp_pSeries_cpu_bootable(unsigned int nr)
 
 	return 1;
 }
-#ifdef CONFIG_MPIC
+
 static struct smp_ops_t pSeries_mpic_smp_ops = {
 	.message_pass	= smp_mpic_message_pass,
 	.probe		= smp_mpic_probe,
 	.kick_cpu	= smp_pSeries_kick_cpu,
 	.setup_cpu	= smp_mpic_setup_cpu,
 };
-#endif
-#ifdef CONFIG_XICS
+
 static struct smp_ops_t pSeries_xics_smp_ops = {
-	.message_pass	= smp_xics_message_pass,
-	.probe		= smp_xics_probe,
+	.message_pass	= NULL,	/* Filled at runtime by xics_smp_probe() */
+	.probe		= xics_smp_probe,
 	.kick_cpu	= smp_pSeries_kick_cpu,
 	.setup_cpu	= smp_xics_setup_cpu,
 	.cpu_bootable	= smp_pSeries_cpu_bootable,
 };
-#endif
 
 /* This is called very early */
 static void __init smp_init_pseries(void)
@@ -245,14 +242,12 @@ static void __init smp_init_pseries(void)
 	pr_debug(" <- smp_init_pSeries()\n");
 }
 
-#ifdef CONFIG_MPIC
 void __init smp_init_pseries_mpic(void)
 {
 	smp_ops = &pSeries_mpic_smp_ops;
 
 	smp_init_pseries();
 }
-#endif
 
 void __init smp_init_pseries_xics(void)
 {
diff --git a/arch/powerpc/platforms/pseries/xics.c b/arch/powerpc/platforms/pseries/xics.c
deleted file mode 100644
index d6901334d66e..000000000000
--- a/arch/powerpc/platforms/pseries/xics.c
+++ /dev/null
@@ -1,949 +0,0 @@
-/*
- * arch/powerpc/platforms/pseries/xics.c
- *
- * Copyright 2000 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/types.h>
-#include <linux/threads.h>
-#include <linux/kernel.h>
-#include <linux/irq.h>
-#include <linux/smp.h>
-#include <linux/interrupt.h>
-#include <linux/init.h>
-#include <linux/radix-tree.h>
-#include <linux/cpu.h>
-#include <linux/msi.h>
-#include <linux/of.h>
-#include <linux/percpu.h>
-
-#include <asm/firmware.h>
-#include <asm/io.h>
-#include <asm/pgtable.h>
-#include <asm/smp.h>
-#include <asm/rtas.h>
-#include <asm/hvcall.h>
-#include <asm/machdep.h>
-
-#include "xics.h"
-#include "plpar_wrappers.h"
-
-static struct irq_host *xics_host;
-
-#define XICS_IPI		2
-#define XICS_IRQ_SPURIOUS	0
-
-/* Want a priority other than 0.  Various HW issues require this. */
-#define	DEFAULT_PRIORITY	5
-
-/*
- * Mark IPIs as higher priority so we can take them inside interrupts that
- * arent marked IRQF_DISABLED
- */
-#define IPI_PRIORITY		4
-
-/* The least favored priority */
-#define LOWEST_PRIORITY		0xFF
-
-/* The number of priorities defined above */
-#define MAX_NUM_PRIORITIES	3
-
-static unsigned int default_server = 0xFF;
-static unsigned int default_distrib_server = 0;
-static unsigned int interrupt_server_size = 8;
-
-/* RTAS service tokens */
-static int ibm_get_xive;
-static int ibm_set_xive;
-static int ibm_int_on;
-static int ibm_int_off;
-
-struct xics_cppr {
-	unsigned char stack[MAX_NUM_PRIORITIES];
-	int index;
-};
-
-static DEFINE_PER_CPU(struct xics_cppr, xics_cppr);
-
-/* Direct hardware low level accessors */
-
-/* The part of the interrupt presentation layer that we care about */
-struct xics_ipl {
-	union {
-		u32 word;
-		u8 bytes[4];
-	} xirr_poll;
-	union {
-		u32 word;
-		u8 bytes[4];
-	} xirr;
-	u32 dummy;
-	union {
-		u32 word;
-		u8 bytes[4];
-	} qirr;
-};
-
-static struct xics_ipl __iomem *xics_per_cpu[NR_CPUS];
-
-static inline unsigned int direct_xirr_info_get(void)
-{
-	int cpu = smp_processor_id();
-
-	return in_be32(&xics_per_cpu[cpu]->xirr.word);
-}
-
-static inline void direct_xirr_info_set(unsigned int value)
-{
-	int cpu = smp_processor_id();
-
-	out_be32(&xics_per_cpu[cpu]->xirr.word, value);
-}
-
-static inline void direct_cppr_info(u8 value)
-{
-	int cpu = smp_processor_id();
-
-	out_8(&xics_per_cpu[cpu]->xirr.bytes[0], value);
-}
-
-static inline void direct_qirr_info(int n_cpu, u8 value)
-{
-	out_8(&xics_per_cpu[n_cpu]->qirr.bytes[0], value);
-}
-
-
-/* LPAR low level accessors */
-
-static inline unsigned int lpar_xirr_info_get(unsigned char cppr)
-{
-	unsigned long lpar_rc;
-	unsigned long return_value;
-
-	lpar_rc = plpar_xirr(&return_value, cppr);
-	if (lpar_rc != H_SUCCESS)
-		panic(" bad return code xirr - rc = %lx\n", lpar_rc);
-	return (unsigned int)return_value;
-}
-
-static inline void lpar_xirr_info_set(unsigned int value)
-{
-	unsigned long lpar_rc;
-
-	lpar_rc = plpar_eoi(value);
-	if (lpar_rc != H_SUCCESS)
-		panic("bad return code EOI - rc = %ld, value=%x\n", lpar_rc,
-		      value);
-}
-
-static inline void lpar_cppr_info(u8 value)
-{
-	unsigned long lpar_rc;
-
-	lpar_rc = plpar_cppr(value);
-	if (lpar_rc != H_SUCCESS)
-		panic("bad return code cppr - rc = %lx\n", lpar_rc);
-}
-
-static inline void lpar_qirr_info(int n_cpu , u8 value)
-{
-	unsigned long lpar_rc;
-
-	lpar_rc = plpar_ipi(get_hard_smp_processor_id(n_cpu), value);
-	if (lpar_rc != H_SUCCESS)
-		panic("bad return code qirr - rc = %lx\n", lpar_rc);
-}
-
-
-/* Interface to generic irq subsystem */
-
-#ifdef CONFIG_SMP
-/*
- * For the moment we only implement delivery to all cpus or one cpu.
- *
- * If the requested affinity is cpu_all_mask, we set global affinity.
- * If not we set it to the first cpu in the mask, even if multiple cpus
- * are set. This is so things like irqbalance (which set core and package
- * wide affinities) do the right thing.
- */
-static int get_irq_server(unsigned int virq, const struct cpumask *cpumask,
-			  unsigned int strict_check)
-{
-
-	if (!distribute_irqs)
-		return default_server;
-
-	if (!cpumask_subset(cpu_possible_mask, cpumask)) {
-		int server = cpumask_first_and(cpu_online_mask, cpumask);
-
-		if (server < nr_cpu_ids)
-			return get_hard_smp_processor_id(server);
-
-		if (strict_check)
-			return -1;
-	}
-
-	/*
-	 * Workaround issue with some versions of JS20 firmware that
-	 * deliver interrupts to cpus which haven't been started. This
-	 * happens when using the maxcpus= boot option.
-	 */
-	if (cpumask_equal(cpu_online_mask, cpu_present_mask))
-		return default_distrib_server;
-
-	return default_server;
-}
-#else
-#define get_irq_server(virq, cpumask, strict_check) (default_server)
-#endif
-
-static void xics_unmask_irq(struct irq_data *d)
-{
-	unsigned int hwirq;
-	int call_status;
-	int server;
-
-	pr_devel("xics: unmask virq %d\n", d->irq);
-
-	hwirq = (unsigned int)irq_map[d->irq].hwirq;
-	pr_devel(" -> map to hwirq 0x%x\n", hwirq);
-	if (hwirq == XICS_IPI || hwirq == XICS_IRQ_SPURIOUS)
-		return;
-
-	server = get_irq_server(d->irq, d->affinity, 0);
-
-	call_status = rtas_call(ibm_set_xive, 3, 1, NULL, hwirq, server,
-				DEFAULT_PRIORITY);
-	if (call_status != 0) {
-		printk(KERN_ERR
-			"%s: ibm_set_xive irq %u server %x returned %d\n",
-			__func__, hwirq, server, call_status);
-		return;
-	}
-
-	/* Now unmask the interrupt (often a no-op) */
-	call_status = rtas_call(ibm_int_on, 1, 1, NULL, hwirq);
-	if (call_status != 0) {
-		printk(KERN_ERR "%s: ibm_int_on irq=%u returned %d\n",
-			__func__, hwirq, call_status);
-		return;
-	}
-}
-
-static unsigned int xics_startup(struct irq_data *d)
-{
-	/*
-	 * 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 (d->msi_desc)
-		unmask_msi_irq(d);
-
-	/* unmask it */
-	xics_unmask_irq(d);
-	return 0;
-}
-
-static void xics_mask_real_irq(unsigned int hwirq)
-{
-	int call_status;
-
-	if (hwirq == XICS_IPI)
-		return;
-
-	call_status = rtas_call(ibm_int_off, 1, 1, NULL, hwirq);
-	if (call_status != 0) {
-		printk(KERN_ERR "%s: ibm_int_off irq=%u returned %d\n",
-			__func__, hwirq, call_status);
-		return;
-	}
-
-	/* Have to set XIVE to 0xff to be able to remove a slot */
-	call_status = rtas_call(ibm_set_xive, 3, 1, NULL, hwirq,
-				default_server, 0xff);
-	if (call_status != 0) {
-		printk(KERN_ERR "%s: ibm_set_xive(0xff) irq=%u returned %d\n",
-			__func__, hwirq, call_status);
-		return;
-	}
-}
-
-static void xics_mask_irq(struct irq_data *d)
-{
-	unsigned int hwirq;
-
-	pr_devel("xics: mask virq %d\n", d->irq);
-
-	hwirq = (unsigned int)irq_map[d->irq].hwirq;
-	if (hwirq == XICS_IPI || hwirq == XICS_IRQ_SPURIOUS)
-		return;
-	xics_mask_real_irq(hwirq);
-}
-
-static void xics_mask_unknown_vec(unsigned int vec)
-{
-	printk(KERN_ERR "Interrupt %u (real) is invalid, disabling it.\n", vec);
-	xics_mask_real_irq(vec);
-}
-
-static inline unsigned int xics_xirr_vector(unsigned int xirr)
-{
-	/*
-	 * The top byte is the old cppr, to be restored on EOI.
-	 * The remaining 24 bits are the vector.
-	 */
-	return xirr & 0x00ffffff;
-}
-
-static void push_cppr(unsigned int vec)
-{
-	struct xics_cppr *os_cppr = &__get_cpu_var(xics_cppr);
-
-	if (WARN_ON(os_cppr->index >= MAX_NUM_PRIORITIES - 1))
-		return;
-
-	if (vec == XICS_IPI)
-		os_cppr->stack[++os_cppr->index] = IPI_PRIORITY;
-	else
-		os_cppr->stack[++os_cppr->index] = DEFAULT_PRIORITY;
-}
-
-static unsigned int xics_get_irq_direct(void)
-{
-	unsigned int xirr = direct_xirr_info_get();
-	unsigned int vec = xics_xirr_vector(xirr);
-	unsigned int irq;
-
-	if (vec == XICS_IRQ_SPURIOUS)
-		return NO_IRQ;
-
-	irq = irq_radix_revmap_lookup(xics_host, vec);
-	if (likely(irq != NO_IRQ)) {
-		push_cppr(vec);
-		return irq;
-	}
-
-	/* We don't have a linux mapping, so have rtas mask it. */
-	xics_mask_unknown_vec(vec);
-
-	/* We might learn about it later, so EOI it */
-	direct_xirr_info_set(xirr);
-	return NO_IRQ;
-}
-
-static unsigned int xics_get_irq_lpar(void)
-{
-	struct xics_cppr *os_cppr = &__get_cpu_var(xics_cppr);
-	unsigned int xirr = lpar_xirr_info_get(os_cppr->stack[os_cppr->index]);
-	unsigned int vec = xics_xirr_vector(xirr);
-	unsigned int irq;
-
-	if (vec == XICS_IRQ_SPURIOUS)
-		return NO_IRQ;
-
-	irq = irq_radix_revmap_lookup(xics_host, vec);
-	if (likely(irq != NO_IRQ)) {
-		push_cppr(vec);
-		return irq;
-	}
-
-	/* We don't have a linux mapping, so have RTAS mask it. */
-	xics_mask_unknown_vec(vec);
-
-	/* We might learn about it later, so EOI it */
-	lpar_xirr_info_set(xirr);
-	return NO_IRQ;
-}
-
-static unsigned char pop_cppr(void)
-{
-	struct xics_cppr *os_cppr = &__get_cpu_var(xics_cppr);
-
-	if (WARN_ON(os_cppr->index < 1))
-		return LOWEST_PRIORITY;
-
-	return os_cppr->stack[--os_cppr->index];
-}
-
-static void xics_eoi_direct(struct irq_data *d)
-{
-	unsigned int hwirq = (unsigned int)irq_map[d->irq].hwirq;
-
-	iosync();
-	direct_xirr_info_set((pop_cppr() << 24) | hwirq);
-}
-
-static void xics_eoi_lpar(struct irq_data *d)
-{
-	unsigned int hwirq = (unsigned int)irq_map[d->irq].hwirq;
-
-	iosync();
-	lpar_xirr_info_set((pop_cppr() << 24) | hwirq);
-}
-
-static int
-xics_set_affinity(struct irq_data *d, const struct cpumask *cpumask, bool force)
-{
-	unsigned int hwirq;
-	int status;
-	int xics_status[2];
-	int irq_server;
-
-	hwirq = (unsigned int)irq_map[d->irq].hwirq;
-	if (hwirq == XICS_IPI || hwirq == XICS_IRQ_SPURIOUS)
-		return -1;
-
-	status = rtas_call(ibm_get_xive, 1, 3, xics_status, hwirq);
-
-	if (status) {
-		printk(KERN_ERR "%s: ibm,get-xive irq=%u returns %d\n",
-			__func__, hwirq, status);
-		return -1;
-	}
-
-	irq_server = get_irq_server(d->irq, cpumask, 1);
-	if (irq_server == -1) {
-		char cpulist[128];
-		cpumask_scnprintf(cpulist, sizeof(cpulist), cpumask);
-		printk(KERN_WARNING
-			"%s: No online cpus in the mask %s for irq %d\n",
-			__func__, cpulist, d->irq);
-		return -1;
-	}
-
-	status = rtas_call(ibm_set_xive, 3, 1, NULL,
-				hwirq, irq_server, xics_status[1]);
-
-	if (status) {
-		printk(KERN_ERR "%s: ibm,set-xive irq=%u returns %d\n",
-			__func__, hwirq, status);
-		return -1;
-	}
-
-	return 0;
-}
-
-static struct irq_chip xics_pic_direct = {
-	.name = "XICS",
-	.irq_startup = xics_startup,
-	.irq_mask = xics_mask_irq,
-	.irq_unmask = xics_unmask_irq,
-	.irq_eoi = xics_eoi_direct,
-	.irq_set_affinity = xics_set_affinity
-};
-
-static struct irq_chip xics_pic_lpar = {
-	.name = "XICS",
-	.irq_startup = xics_startup,
-	.irq_mask = xics_mask_irq,
-	.irq_unmask = xics_unmask_irq,
-	.irq_eoi = xics_eoi_lpar,
-	.irq_set_affinity = xics_set_affinity
-};
-
-
-/* Interface to arch irq controller subsystem layer */
-
-/* Points to the irq_chip we're actually using */
-static struct irq_chip *xics_irq_chip;
-
-static int xics_host_match(struct irq_host *h, struct device_node *node)
-{
-	/* IBM machines have interrupt parents of various funky types for things
-	 * like vdevices, events, etc... The trick we use here is to match
-	 * everything here except the legacy 8259 which is compatible "chrp,iic"
-	 */
-	return !of_device_is_compatible(node, "chrp,iic");
-}
-
-static int xics_host_map(struct irq_host *h, unsigned int virq,
-			 irq_hw_number_t hw)
-{
-	pr_devel("xics: map virq %d, hwirq 0x%lx\n", virq, hw);
-
-	/* Insert the interrupt mapping into the radix tree for fast lookup */
-	irq_radix_revmap_insert(xics_host, virq, hw);
-
-	irq_set_status_flags(virq, IRQ_LEVEL);
-	irq_set_chip_and_handler(virq, xics_irq_chip, handle_fasteoi_irq);
-	return 0;
-}
-
-static int xics_host_xlate(struct irq_host *h, struct device_node *ct,
-			   const u32 *intspec, unsigned int intsize,
-			   irq_hw_number_t *out_hwirq, unsigned int *out_flags)
-
-{
-	/* Current xics implementation translates everything
-	 * to level. It is not technically right for MSIs but this
-	 * is irrelevant at this point. We might get smarter in the future
-	 */
-	*out_hwirq = intspec[0];
-	*out_flags = IRQ_TYPE_LEVEL_LOW;
-
-	return 0;
-}
-
-static struct irq_host_ops xics_host_ops = {
-	.match = xics_host_match,
-	.map = xics_host_map,
-	.xlate = xics_host_xlate,
-};
-
-static void __init xics_init_host(void)
-{
-	if (firmware_has_feature(FW_FEATURE_LPAR))
-		xics_irq_chip = &xics_pic_lpar;
-	else
-		xics_irq_chip = &xics_pic_direct;
-
-	xics_host = irq_alloc_host(NULL, IRQ_HOST_MAP_TREE, 0, &xics_host_ops,
-				   XICS_IRQ_SPURIOUS);
-	BUG_ON(xics_host == NULL);
-	irq_set_default_host(xics_host);
-}
-
-
-/* Inter-processor interrupt support */
-
-#ifdef CONFIG_SMP
-/*
- * XICS only has a single IPI, so encode the messages per CPU
- */
-static DEFINE_PER_CPU_SHARED_ALIGNED(unsigned long, xics_ipi_message);
-
-static inline void smp_xics_do_message(int cpu, int msg)
-{
-	unsigned long *tgt = &per_cpu(xics_ipi_message, cpu);
-
-	set_bit(msg, tgt);
-	mb();
-	if (firmware_has_feature(FW_FEATURE_LPAR))
-		lpar_qirr_info(cpu, IPI_PRIORITY);
-	else
-		direct_qirr_info(cpu, IPI_PRIORITY);
-}
-
-void smp_xics_message_pass(int target, int msg)
-{
-	unsigned int i;
-
-	if (target < NR_CPUS) {
-		smp_xics_do_message(target, msg);
-	} else {
-		for_each_online_cpu(i) {
-			if (target == MSG_ALL_BUT_SELF
-			    && i == smp_processor_id())
-				continue;
-			smp_xics_do_message(i, msg);
-		}
-	}
-}
-
-static irqreturn_t xics_ipi_dispatch(int cpu)
-{
-	unsigned long *tgt = &per_cpu(xics_ipi_message, cpu);
-
-	mb();	/* order mmio clearing qirr */
-	while (*tgt) {
-		if (test_and_clear_bit(PPC_MSG_CALL_FUNCTION, tgt)) {
-			smp_message_recv(PPC_MSG_CALL_FUNCTION);
-		}
-		if (test_and_clear_bit(PPC_MSG_RESCHEDULE, tgt)) {
-			smp_message_recv(PPC_MSG_RESCHEDULE);
-		}
-		if (test_and_clear_bit(PPC_MSG_CALL_FUNC_SINGLE, tgt)) {
-			smp_message_recv(PPC_MSG_CALL_FUNC_SINGLE);
-		}
-#if defined(CONFIG_DEBUGGER) || defined(CONFIG_KEXEC)
-		if (test_and_clear_bit(PPC_MSG_DEBUGGER_BREAK, tgt)) {
-			smp_message_recv(PPC_MSG_DEBUGGER_BREAK);
-		}
-#endif
-	}
-	return IRQ_HANDLED;
-}
-
-static irqreturn_t xics_ipi_action_direct(int irq, void *dev_id)
-{
-	int cpu = smp_processor_id();
-
-	direct_qirr_info(cpu, 0xff);
-
-	return xics_ipi_dispatch(cpu);
-}
-
-static irqreturn_t xics_ipi_action_lpar(int irq, void *dev_id)
-{
-	int cpu = smp_processor_id();
-
-	lpar_qirr_info(cpu, 0xff);
-
-	return xics_ipi_dispatch(cpu);
-}
-
-static void xics_request_ipi(void)
-{
-	unsigned int ipi;
-	int rc;
-
-	ipi = irq_create_mapping(xics_host, XICS_IPI);
-	BUG_ON(ipi == NO_IRQ);
-
-	/*
-	 * IPIs are marked IRQF_DISABLED as they must run with irqs
-	 * disabled
-	 */
-	irq_set_handler(ipi, handle_percpu_irq);
-	if (firmware_has_feature(FW_FEATURE_LPAR))
-		rc = request_irq(ipi, xics_ipi_action_lpar,
-				IRQF_DISABLED|IRQF_PERCPU, "IPI", NULL);
-	else
-		rc = request_irq(ipi, xics_ipi_action_direct,
-				IRQF_DISABLED|IRQF_PERCPU, "IPI", NULL);
-	BUG_ON(rc);
-}
-
-int __init smp_xics_probe(void)
-{
-	xics_request_ipi();
-
-	return cpumask_weight(cpu_possible_mask);
-}
-
-#endif /* CONFIG_SMP */
-
-
-/* Initialization */
-
-static void xics_update_irq_servers(void)
-{
-	int i, j;
-	struct device_node *np;
-	u32 ilen;
-	const u32 *ireg;
-	u32 hcpuid;
-