Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

Pull powerpc updates from Benjamin Herrenschmidt:
 "So from the depth of frozen Minnesota, here's the powerpc pull request
  for 3.9.  It has a few interesting highlights, in addition to the
  usual bunch of bug fixes, minor updates, embedded device tree updates
  and new boards:

   - Hand tuned asm implementation of SHA1 (by Paulus & Michael
     Ellerman)

   - Support for Doorbell interrupts on Power8 (kind of fast
     thread-thread IPIs) by Ian Munsie

   - Long overdue cleanup of the way we handle relocation of our open
     firmware trampoline (prom_init.c) on 64-bit by Anton Blanchard

   - Support for saving/restoring & context switching the PPR (Processor
     Priority Register) on server processors that support it.  This
     allows the kernel to preserve thread priorities established by
     userspace.  By Haren Myneni.

   - DAWR (new watchpoint facility) support on Power8 by Michael Neuling

   - Ability to change the DSCR (Data Stream Control Register) which
     controls cache prefetching on a running process via ptrace by
     Alexey Kardashevskiy

   - Support for context switching the TAR register on Power8 (new
     branch target register meant to be used by some new specific
     userspace perf event interrupt facility which is yet to be enabled)
     by Ian Munsie.

   - Improve preservation of the CFAR register (which captures the
     origin of a branch) on various exception conditions by Paulus.

   - Move the Bestcomm DMA driver from arch powerpc to drivers/dma where
     it belongs by Philippe De Muyter

   - Support for Transactional Memory on Power8 by Michael Neuling
     (based on original work by Matt Evans).  For those curious about
     the feature, the patch contains a pretty good description."

(See commit db8ff907027b: "powerpc: Documentation for transactional
memory on powerpc" for the mentioned description added to the file
Documentation/powerpc/transactional_memory.txt)

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (140 commits)
  powerpc/kexec: Disable hard IRQ before kexec
  powerpc/85xx: l2sram - Add compatible string for BSC9131 platform
  powerpc/85xx: bsc9131 - Correct typo in SDHC device node
  powerpc/e500/qemu-e500: enable coreint
  powerpc/mpic: allow coreint to be determined by MPIC version
  powerpc/fsl_pci: Store the pci ctlr device ptr in the pci ctlr struct
  powerpc/85xx: Board support for ppa8548
  powerpc/fsl: remove extraneous DIU platform functions
  arch/powerpc/platforms/85xx/p1022_ds.c: adjust duplicate test
  powerpc: Documentation for transactional memory on powerpc
  powerpc: Add transactional memory to pseries and ppc64 defconfigs
  powerpc: Add config option for transactional memory
  powerpc: Add transactional memory to POWER8 cpu features
  powerpc: Add new transactional memory state to the signal context
  powerpc: Hook in new transactional memory code
  powerpc: Routines for FP/VSX/VMX unavailable during a transaction
  powerpc: Add transactional memory unavaliable execption handler
  powerpc: Add reclaim and recheckpoint functions for context switching transactional memory processes
  powerpc: Add FP/VSX and VMX register load functions for transactional memory
  powerpc: Add helper functions for transactional memory context switching
  ...

11 files changed, 176 insertions, 95 deletions

diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig
index 837cf49357e..9a0941bc4d3 100644
--- a/arch/powerpc/platforms/pseries/Kconfig
+++ b/arch/powerpc/platforms/pseries/Kconfig
@@ -17,6 +17,7 @@ config PPC_PSERIES
 	select PPC_NATIVE
 	select PPC_PCI_CHOICE if EXPERT
 	select ZLIB_DEFLATE
+	select PPC_DOORBELL
 	default y
 
 config PPC_SPLPAR
diff --git a/arch/powerpc/platforms/pseries/Makefile b/arch/powerpc/platforms/pseries/Makefile
index 890622b87c8..53866e537a9 100644
--- a/arch/powerpc/platforms/pseries/Makefile
+++ b/arch/powerpc/platforms/pseries/Makefile
@@ -1,4 +1,4 @@
-ccflags-$(CONFIG_PPC64)			:= -mno-minimal-toc
+ccflags-$(CONFIG_PPC64)			:= $(NO_MINIMAL_TOC)
 ccflags-$(CONFIG_PPC_PSERIES_DEBUG)	+= -DDEBUG
 
 obj-y			:= lpar.o hvCall.o nvram.o reconfig.o \
diff --git a/arch/powerpc/platforms/pseries/eeh.c b/arch/powerpc/platforms/pseries/eeh.c
index 9a04322b173..6b73d6c44f5 100644
--- a/arch/powerpc/platforms/pseries/eeh.c
+++ b/arch/powerpc/platforms/pseries/eeh.c
@@ -788,7 +788,6 @@ static void eeh_add_device_late(struct pci_dev *dev)
 	dev->dev.archdata.edev = edev;
 
 	eeh_addr_cache_insert_dev(dev);
-	eeh_sysfs_add_device(dev);
 }
 
 /**
@@ -815,6 +814,29 @@ void eeh_add_device_tree_late(struct pci_bus *bus)
 EXPORT_SYMBOL_GPL(eeh_add_device_tree_late);
 
 /**
+ * eeh_add_sysfs_files - Add EEH sysfs files for the indicated PCI bus
+ * @bus: PCI bus
+ *
+ * This routine must be used to add EEH sysfs files for PCI
+ * devices which are attached to the indicated PCI bus. The PCI bus
+ * is added after system boot through hotplug or dlpar.
+ */
+void eeh_add_sysfs_files(struct pci_bus *bus)
+{
+	struct pci_dev *dev;
+
+	list_for_each_entry(dev, &bus->devices, bus_list) {
+		eeh_sysfs_add_device(dev);
+		if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
+			struct pci_bus *subbus = dev->subordinate;
+			if (subbus)
+				eeh_add_sysfs_files(subbus);
+		}
+	}
+}
+EXPORT_SYMBOL_GPL(eeh_add_sysfs_files);
+
+/**
  * eeh_remove_device - Undo EEH setup for the indicated pci device
  * @dev: pci device to be removed
  * @purge_pe: remove the PE or not
diff --git a/arch/powerpc/platforms/pseries/firmware.c b/arch/powerpc/platforms/pseries/firmware.c
index 7b56118f531..aa3693f7fb2 100644
--- a/arch/powerpc/platforms/pseries/firmware.c
+++ b/arch/powerpc/platforms/pseries/firmware.c
@@ -33,6 +33,11 @@ typedef struct {
     char * name;
 } firmware_feature_t;
 
+/*
+ * The names in this table match names in rtas/ibm,hypertas-functions.  If the
+ * entry ends in a '*', only upto the '*' is matched.  Otherwise the entire
+ * string must match.
+ */
 static __initdata firmware_feature_t
 firmware_features_table[FIRMWARE_MAX_FEATURES] = {
 	{FW_FEATURE_PFT,		"hcall-pft"},
@@ -57,6 +62,7 @@ firmware_features_table[FIRMWARE_MAX_FEATURES] = {
 	{FW_FEATURE_SPLPAR,		"hcall-splpar"},
 	{FW_FEATURE_VPHN,		"hcall-vphn"},
 	{FW_FEATURE_SET_MODE,		"hcall-set-mode"},
+	{FW_FEATURE_BEST_ENERGY,	"hcall-best-energy-1*"},
 };
 
 /* Build up the firmware features bitmask using the contents of
@@ -72,9 +78,20 @@ void __init fw_feature_init(const char *hypertas, unsigned long len)
 
 	for (s = hypertas; s < hypertas + len; s += strlen(s) + 1) {
 		for (i = 0; i < FIRMWARE_MAX_FEATURES; i++) {
+			const char *name = firmware_features_table[i].name;
+			size_t size;
 			/* check value against table of strings */
-			if (!firmware_features_table[i].name ||
-			    strcmp(firmware_features_table[i].name, s))
+			if (!name)
+				continue;
+			/*
+			 * If there is a '*' at the end of name, only check
+			 * upto there
+			 */
+			size = strlen(name);
+			if (size && name[size - 1] == '*') {
+				if (strncmp(name, s, size - 1))
+					continue;
+			} else if (strcmp(name, s))
 				continue;
 
 			/* we have a match */
diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c
index a38956269fb..217ca5c75b2 100644
--- a/arch/powerpc/platforms/pseries/hotplug-cpu.c
+++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c
@@ -127,9 +127,16 @@ static void pseries_mach_cpu_die(void)
 			get_lppaca()->donate_dedicated_cpu = 1;
 
 		while (get_preferred_offline_state(cpu) == CPU_STATE_INACTIVE) {
+			while (!prep_irq_for_idle()) {
+				local_irq_enable();
+				local_irq_disable();
+			}
+
 			extended_cede_processor(cede_latency_hint);
 		}
 
+		local_irq_disable();
+
 		if (!get_lppaca()->shared_proc)
 			get_lppaca()->donate_dedicated_cpu = 0;
 		get_lppaca()->idle = 0;
@@ -137,6 +144,7 @@ static void pseries_mach_cpu_die(void)
 		if (get_preferred_offline_state(cpu) == CPU_STATE_ONLINE) {
 			unregister_slb_shadow(hwcpu);
 
+			hard_irq_disable();
 			/*
 			 * Call to start_secondary_resume() will not return.
 			 * Kernel stack will be reset and start_secondary()
diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c
index e2685badb5d..1b2a174e7c5 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c
@@ -382,6 +382,7 @@ static int tce_clearrange_multi_pSeriesLP(unsigned long start_pfn,
 		rc = plpar_tce_stuff((u64)be32_to_cpu(maprange->liobn),
 					     dma_offset,
 					     0, limit);
+		next += limit * tce_size;
 		num_tce -= limit;
 	} while (num_tce > 0 && !rc);
 
@@ -786,33 +787,68 @@ static u64 find_existing_ddw(struct device_node *pdn)
 	return dma_addr;
 }
 
+static void __restore_default_window(struct eeh_dev *edev,
+						u32 ddw_restore_token)
+{
+	u32 cfg_addr;
+	u64 buid;
+	int ret;
+
+	/*
+	 * Get the config address and phb buid of the PE window.
+	 * Rely on eeh to retrieve this for us.
+	 * Retrieve them from the pci device, not the node with the
+	 * dma-window property
+	 */
+	cfg_addr = edev->config_addr;
+	if (edev->pe_config_addr)
+		cfg_addr = edev->pe_config_addr;
+	buid = edev->phb->buid;
+
+	do {
+		ret = rtas_call(ddw_restore_token, 3, 1, NULL, cfg_addr,
+					BUID_HI(buid), BUID_LO(buid));
+	} while (rtas_busy_delay(ret));
+	pr_info("ibm,reset-pe-dma-windows(%x) %x %x %x returned %d\n",
+		 ddw_restore_token, cfg_addr, BUID_HI(buid), BUID_LO(buid), ret);
+}
+
 static int find_existing_ddw_windows(void)
 {
-	int len;
 	struct device_node *pdn;
-	struct direct_window *window;
 	const struct dynamic_dma_window_prop *direct64;
+	const u32 *ddw_extensions;
 
 	if (!firmware_has_feature(FW_FEATURE_LPAR))
 		return 0;
 
 	for_each_node_with_property(pdn, DIRECT64_PROPNAME) {
-		direct64 = of_get_property(pdn, DIRECT64_PROPNAME, &len);
+		direct64 = of_get_property(pdn, DIRECT64_PROPNAME, NULL);
 		if (!direct64)
 			continue;
 
-		window = kzalloc(sizeof(*window), GFP_KERNEL);
-		if (!window || len < sizeof(struct dynamic_dma_window_prop)) {
-			kfree(window);
-			remove_ddw(pdn);
-			continue;
-		}
+		/*
+		 * We need to ensure the IOMMU table is active when we
+		 * return from the IOMMU setup so that the common code
+		 * can clear the table or find the holes. To that end,
+		 * first, remove any existing DDW configuration.
+		 */
+		remove_ddw(pdn);
 
-		window->device = pdn;
-		window->prop = direct64;
-		spin_lock(&direct_window_list_lock);
-		list_add(&window->list, &direct_window_list);
-		spin_unlock(&direct_window_list_lock);
+		/*
+		 * Second, if we are running on a new enough level of
+		 * firmware where the restore API is present, use it to
+		 * restore the 32-bit window, which was removed in
+		 * create_ddw.
+		 * If the API is not present, then create_ddw couldn't
+		 * have removed the 32-bit window in the first place, so
+		 * removing the DDW configuration should be sufficient.
+		 */
+		ddw_extensions = of_get_property(pdn, "ibm,ddw-extensions",
+									NULL);
+		if (ddw_extensions && ddw_extensions[0] > 0)
+			__restore_default_window(of_node_to_eeh_dev(pdn),
+							ddw_extensions[1]);
 	}
 
 	return 0;
@@ -883,32 +919,9 @@ static int create_ddw(struct pci_dev *dev, const u32 *ddw_avail,
 }
 
 static void restore_default_window(struct pci_dev *dev,
-				u32 ddw_restore_token, unsigned long liobn)
+					u32 ddw_restore_token)
 {
-	struct eeh_dev *edev;
-	u32 cfg_addr;
-	u64 buid;
-	int ret;
-
-	/*
-	 * Get the config address and phb buid of the PE window.
-	 * Rely on eeh to retrieve this for us.
-	 * Retrieve them from the pci device, not the node with the
-	 * dma-window property
-	 */
-	edev = pci_dev_to_eeh_dev(dev);
-	cfg_addr = edev->config_addr;
-	if (edev->pe_config_addr)
-		cfg_addr = edev->pe_config_addr;
-	buid = edev->phb->buid;
-
-	do {
-		ret = rtas_call(ddw_restore_token, 3, 1, NULL, cfg_addr,
-					BUID_HI(buid), BUID_LO(buid));
-	} while (rtas_busy_delay(ret));
-	dev_info(&dev->dev,
-		"ibm,reset-pe-dma-windows(%x) %x %x %x returned %d\n",
-		 ddw_restore_token, cfg_addr, BUID_HI(buid), BUID_LO(buid), ret);
+	__restore_default_window(pci_dev_to_eeh_dev(dev), ddw_restore_token);
 }
 
 /*
@@ -1099,7 +1112,7 @@ out_free_prop:
 
 out_restore_window:
 	if (ddw_restore_token)
-		restore_default_window(dev, ddw_restore_token, liobn);
+		restore_default_window(dev, ddw_restore_token);
 
 out_unlock:
 	mutex_unlock(&direct_window_init_mutex);
@@ -1295,6 +1308,7 @@ static int iommu_reconfig_notifier(struct notifier_block *nb, unsigned long acti
 
 	switch (action) {
 	case OF_RECONFIG_DETACH_NODE:
+		remove_ddw(np);
 		if (pci && pci->iommu_table)
 			iommu_free_table(pci->iommu_table, np->full_name);
 
@@ -1307,16 +1321,6 @@ static int iommu_reconfig_notifier(struct notifier_block *nb, unsigned long acti
 			}
 		}
 		spin_unlock(&direct_window_list_lock);
-
-		/*
-		 * Because the notifier runs after isolation of the
-		 * slot, we are guaranteed any DMA window has already
-		 * been revoked and the TCEs have been marked invalid,
-		 * so we don't need a call to remove_ddw(np). However,
-		 * if an additional notifier action is added before the
-		 * isolate call, we should update this code for
-		 * completeness with such a call.
-		 */
 		break;
 	default:
 		err = NOTIFY_DONE;
diff --git a/arch/powerpc/platforms/pseries/pci.c b/arch/powerpc/platforms/pseries/pci.c
index 56b864d777e..0b580f413a9 100644
--- a/arch/powerpc/platforms/pseries/pci.c
+++ b/arch/powerpc/platforms/pseries/pci.c
@@ -40,7 +40,8 @@ void pcibios_name_device(struct pci_dev *dev)
 	 */
 	dn = pci_device_to_OF_node(dev);
 	if (dn) {
-		const char *loc_code = of_get_property(dn, "ibm,loc-code", 0);
+		const char *loc_code = of_get_property(dn, "ibm,loc-code",
+				NULL);
 		if (loc_code) {
 			int loc_len = strlen(loc_code);
 			if (loc_len < sizeof(dev->dev.name)) {
diff --git a/arch/powerpc/platforms/pseries/plpar_wrappers.h b/arch/powerpc/platforms/pseries/plpar_wrappers.h
index e6cc34a6705..f368668d97b 100644
--- a/arch/powerpc/platforms/pseries/plpar_wrappers.h
+++ b/arch/powerpc/platforms/pseries/plpar_wrappers.h
@@ -2,6 +2,7 @@
 #define _PSERIES_PLPAR_WRAPPERS_H
 
 #include <linux/string.h>
+#include <linux/irqflags.h>
 
 #include <asm/hvcall.h>
 #include <asm/paca.h>
@@ -41,7 +42,14 @@ static inline long extended_cede_processor(unsigned long latency_hint)
 	u8 old_latency_hint = get_cede_latency_hint();
 
 	set_cede_latency_hint(latency_hint);
+
 	rc = cede_processor();
+#ifdef CONFIG_TRACE_IRQFLAGS
+		/* Ensure that H_CEDE returns with IRQs on */
+		if (WARN_ON(!(mfmsr() & MSR_EE)))
+			__hard_irq_enable();
+#endif
+
 	set_cede_latency_hint(old_latency_hint);
 
 	return rc;
@@ -304,4 +312,14 @@ static inline long disable_reloc_on_exceptions(void) {
 	return plpar_set_mode(0, 3, 0, 0);
 }
 
+static inline long plapr_set_ciabr(unsigned long ciabr)
+{
+	return plpar_set_mode(0, 1, ciabr, 0);
+}
+
+static inline long plapr_set_watchpoint0(unsigned long dawr0, unsigned long dawrx0)
+{
+	return plpar_set_mode(0, 2, dawr0, dawrx0);
+}
+
 #endif /* _PSERIES_PLPAR_WRAPPERS_H */
diff --git a/arch/powerpc/platforms/pseries/pseries_energy.c b/arch/powerpc/platforms/pseries/pseries_energy.c
index af281dce510..a91e6dadda2 100644
--- a/arch/powerpc/platforms/pseries/pseries_energy.c
+++ b/arch/powerpc/platforms/pseries/pseries_energy.c
@@ -21,6 +21,7 @@
 #include <asm/cputhreads.h>
 #include <asm/page.h>
 #include <asm/hvcall.h>
+#include <asm/firmware.h>
 
 
 #define MODULE_VERS "1.0"
@@ -32,40 +33,6 @@ static int sysfs_entries;
 
 /* Helper routines */
 
-/*
- * Routine to detect firmware support for hcall
- * return 1 if H_BEST_ENERGY is supported
- * else return 0
- */
-
-static int check_for_h_best_energy(void)
-{
-	struct device_node *rtas = NULL;
-	const char *hypertas, *s;
-	int length;
-	int rc = 0;
-
-	rtas = of_find_node_by_path("/rtas");
-	if (!rtas)
-		return 0;
-
-	hypertas = of_get_property(rtas, "ibm,hypertas-functions", &length);
-	if (!hypertas) {
-		of_node_put(rtas);
-		return 0;
-	}
-
-	/* hypertas will have list of strings with hcall names */
-	for (s = hypertas; s < hypertas + length; s += strlen(s) + 1) {
-		if (!strncmp("hcall-best-energy-1", s, 19)) {
-			rc = 1; /* Found the string */
-			break;
-		}
-	}
-	of_node_put(rtas);
-	return rc;
-}
-
 /* Helper Routines to convert between drc_index to cpu numbers */
 
 static u32 cpu_to_drc_index(int cpu)
@@ -262,7 +229,7 @@ static int __init pseries_energy_init(void)
 	int cpu, err;
 	struct device *cpu_dev;
 
-	if (!check_for_h_best_energy()) {
+	if (!firmware_has_feature(FW_FEATURE_BEST_ENERGY)) {
 		printk(KERN_INFO "Hypercall H_BEST_ENERGY not supported\n");
 		return 0;
 	}
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 527e12c9573..8bcc9ca6682 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -65,6 +65,7 @@
 #include <asm/smp.h>
 #include <asm/firmware.h>
 #include <asm/eeh.h>
+#include <asm/reg.h>
 
 #include "plpar_wrappers.h"
 #include "pseries.h"
@@ -375,7 +376,7 @@ static void pSeries_idle(void)
  * to ever be a problem in practice we can move this into a kernel thread to
  * finish off the process later in boot.
  */
-static int __init pSeries_enable_reloc_on_exc(void)
+long pSeries_enable_reloc_on_exc(void)
 {
 	long rc;
 	unsigned int delay, total_delay = 0;
@@ -397,9 +398,9 @@ static int __init pSeries_enable_reloc_on_exc(void)
 		mdelay(delay);
 	}
 }
+EXPORT_SYMBOL(pSeries_enable_reloc_on_exc);
 
-#ifdef CONFIG_KEXEC
-static long pSeries_disable_reloc_on_exc(void)
+long pSeries_disable_reloc_on_exc(void)
 {
 	long rc;
 
@@ -410,7 +411,9 @@ static long pSeries_disable_reloc_on_exc(void)
 		mdelay(get_longbusy_msecs(rc));
 	}
 }
+EXPORT_SYMBOL(pSeries_disable_reloc_on_exc);
 
+#ifdef CONFIG_KEXEC
 static void pSeries_machine_kexec(struct kimage *image)
 {
 	long rc;
@@ -498,6 +501,14 @@ static int pseries_set_xdabr(unsigned long dabr, unsigned long dabrx)
 	return plpar_hcall_norets(H_SET_XDABR, dabr, dabrx);
 }
 
+static int pseries_set_dawr(unsigned long dawr, unsigned long dawrx)
+{
+	/* PAPR says we can't set HYP */
+	dawrx &= ~DAWRX_HYP;
+
+	return  plapr_set_watchpoint0(dawr, dawrx);
+}
+
 #define CMO_CHARACTERISTICS_TOKEN 44
 #define CMO_MAXLENGTH 1026
 
@@ -604,6 +615,9 @@ static void __init pSeries_init_early(void)
 	else if (firmware_has_feature(FW_FEATURE_DABR))
 		ppc_md.set_dabr = pseries_set_dabr;
 
+	if (firmware_has_feature(FW_FEATURE_SET_MODE))
+		ppc_md.set_dawr = pseries_set_dawr;
+
 	pSeries_cmo_feature_init();
 	iommu_init_early_pSeries();
 
diff --git a/arch/powerpc/platforms/pseries/smp.c b/arch/powerpc/platforms/pseries/smp.c
index 80cd0be71e0..12bc8c3663a 100644
--- a/arch/powerpc/platforms/pseries/smp.c
+++ b/arch/powerpc/platforms/pseries/smp.c
@@ -42,6 +42,7 @@
 #include <asm/vdso_datapage.h>
 #include <asm/cputhreads.h>
 #include <asm/xics.h>
+#include <asm/dbell.h>
 
 #include "plpar_wrappers.h"
 #include "pseries.h"
@@ -54,6 +55,11 @@
  */
 static cpumask_var_t of_spin_mask;
 
+/*
+ * If we multiplex IPI mechanisms, store the appropriate XICS IPI mechanism here
+ */
+static void  (*xics_cause_ipi)(int cpu, unsigned long data);
+
 /* Query where a cpu is now.  Return codes #defined in plpar_wrappers.h */
 int smp_query_cpu_stopped(unsigned int pcpu)
 {
@@ -137,6 +143,8 @@ static void smp_xics_setup_cpu(int cpu)
 {
 	if (cpu != boot_cpuid)
 		xics_setup_cpu();
+	if (cpu_has_feature(CPU_FTR_DBELL))
+		doorbell_setup_this_cpu();
 
 	if (firmware_has_feature(FW_FEATURE_SPLPAR))
 		vpa_init(cpu);
@@ -195,6 +203,27 @@ static int smp_pSeries_cpu_bootable(unsigned int nr)
 	return 1;
 }
 
+/* Only used on systems that support multiple IPI mechanisms */
+static void pSeries_cause_ipi_mux(int cpu, unsigned long data)
+{
+	if (cpumask_test_cpu(cpu, cpu_sibling_mask(smp_processor_id())))
+		doorbell_cause_ipi(cpu, data);
+	else
+		xics_cause_ipi(cpu, data);
+}
+
+static __init int pSeries_smp_probe(void)
+{
+	int ret = xics_smp_probe();
+
+	if (cpu_has_feature(CPU_FTR_DBELL)) {
+		xics_cause_ipi = smp_ops->cause_ipi;
+		smp_ops->cause_ipi = pSeries_cause_ipi_mux;
+	}
+
+	return ret;
+}
+
 static struct smp_ops_t pSeries_mpic_smp_ops = {
 	.message_pass	= smp_mpic_message_pass,
 	.probe		= smp_mpic_probe,
@@ -204,8 +233,8 @@ static struct smp_ops_t pSeries_mpic_smp_ops = {
 
 static struct smp_ops_t pSeries_xics_smp_ops = {
 	.message_pass	= NULL,	/* Use smp_muxed_ipi_message_pass */
-	.cause_ipi	= NULL,	/* Filled at runtime by xics_smp_probe() */
-	.probe		= xics_smp_probe,
+	.cause_ipi	= NULL,	/* Filled at runtime by pSeries_smp_probe() */
+	.probe		= pSeries_smp_probe,
 	.kick_cpu	= smp_pSeries_kick_cpu,
 	.setup_cpu	= smp_xics_setup_cpu,
 	.cpu_bootable	= smp_pSeries_cpu_bootable,