Merge branch 'master' of /repos/git/net-next-2.6

11 files changed, 579 insertions, 31 deletions

diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig
index 3139814f643..5d1b743dbe7 100644
--- a/arch/powerpc/platforms/pseries/Kconfig
+++ b/arch/powerpc/platforms/pseries/Kconfig
@@ -33,6 +33,16 @@ config PSERIES_MSI
        depends on PCI_MSI && EEH
        default y
 
+config PSERIES_ENERGY
+	tristate "pSeries energy management capabilities driver"
+	depends on PPC_PSERIES
+	default y
+	help
+	  Provides interface to platform energy management capabilities
+	  on supported PSERIES platforms.
+	  Provides: /sys/devices/system/cpu/pseries_(de)activation_hint_list
+	  and /sys/devices/system/cpu/cpuN/pseries_(de)activation_hint
+
 config SCANLOG
 	tristate "Scanlog dump interface"
 	depends on RTAS_PROC && PPC_PSERIES
diff --git a/arch/powerpc/platforms/pseries/Makefile b/arch/powerpc/platforms/pseries/Makefile
index 59eb8bdaa79..fc5237810ec 100644
--- a/arch/powerpc/platforms/pseries/Makefile
+++ b/arch/powerpc/platforms/pseries/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_EEH)	+= eeh.o eeh_cache.o eeh_driver.o eeh_event.o eeh_sysfs.o
 obj-$(CONFIG_KEXEC)	+= kexec.o
 obj-$(CONFIG_PCI)	+= pci.o pci_dlpar.o
 obj-$(CONFIG_PSERIES_MSI)	+= msi.o
+obj-$(CONFIG_PSERIES_ENERGY)	+= pseries_energy.o
 
 obj-$(CONFIG_HOTPLUG_CPU)	+= hotplug-cpu.o
 obj-$(CONFIG_MEMORY_HOTPLUG)	+= hotplug-memory.o
diff --git a/arch/powerpc/platforms/pseries/eeh_sysfs.c b/arch/powerpc/platforms/pseries/eeh_sysfs.c
index 15e13b56890..23982c7892d 100644
--- a/arch/powerpc/platforms/pseries/eeh_sysfs.c
+++ b/arch/powerpc/platforms/pseries/eeh_sysfs.c
@@ -25,7 +25,6 @@
 #include <linux/pci.h>
 #include <asm/ppc-pci.h>
 #include <asm/pci-bridge.h>
-#include <linux/kobject.h>
 
 /**
  * EEH_SHOW_ATTR -- create sysfs entry for eeh statistic
diff --git a/arch/powerpc/platforms/pseries/firmware.c b/arch/powerpc/platforms/pseries/firmware.c
index 0a14d8cd314..0b0eff0cce3 100644
--- a/arch/powerpc/platforms/pseries/firmware.c
+++ b/arch/powerpc/platforms/pseries/firmware.c
@@ -55,6 +55,7 @@ firmware_features_table[FIRMWARE_MAX_FEATURES] = {
 	{FW_FEATURE_XDABR,		"hcall-xdabr"},
 	{FW_FEATURE_MULTITCE,		"hcall-multi-tce"},
 	{FW_FEATURE_SPLPAR,		"hcall-splpar"},
+	{FW_FEATURE_VPHN,		"hcall-vphn"},
 };
 
 /* Build up the firmware features bitmask using the contents of
diff --git a/arch/powerpc/platforms/pseries/hvCall.S b/arch/powerpc/platforms/pseries/hvCall.S
index 48d20573e4d..fd05fdee576 100644
--- a/arch/powerpc/platforms/pseries/hvCall.S
+++ b/arch/powerpc/platforms/pseries/hvCall.S
@@ -11,6 +11,7 @@
 #include <asm/processor.h>
 #include <asm/ppc_asm.h>
 #include <asm/asm-offsets.h>
+#include <asm/ptrace.h>
 	
 #define STK_PARM(i)     (48 + ((i)-3)*8)
 
diff --git a/arch/powerpc/platforms/pseries/hvCall_inst.c b/arch/powerpc/platforms/pseries/hvCall_inst.c
index e19ff021e71..f106662f438 100644
--- a/arch/powerpc/platforms/pseries/hvCall_inst.c
+++ b/arch/powerpc/platforms/pseries/hvCall_inst.c
@@ -55,7 +55,7 @@ static void hc_stop(struct seq_file *m, void *p)
 static int hc_show(struct seq_file *m, void *p)
 {
 	unsigned long h_num = (unsigned long)p;
-	struct hcall_stats *hs = (struct hcall_stats *)m->private;
+	struct hcall_stats *hs = m->private;
 
 	if (hs[h_num].num_calls) {
 		if (cpu_has_feature(CPU_FTR_PURR))
diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c
index a77bcaed80a..edea60b7ee9 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c
@@ -140,7 +140,7 @@ static int tce_build_pSeriesLP(struct iommu_table *tbl, long tcenum,
 	return ret;
 }
 
-static DEFINE_PER_CPU(u64 *, tce_page) = NULL;
+static DEFINE_PER_CPU(u64 *, tce_page);
 
 static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum,
 				     long npages, unsigned long uaddr,
@@ -323,14 +323,13 @@ static void iommu_table_setparms(struct pci_controller *phb,
 static void iommu_table_setparms_lpar(struct pci_controller *phb,
 				      struct device_node *dn,
 				      struct iommu_table *tbl,
-				      const void *dma_window,
-				      int bussubno)
+				      const void *dma_window)
 {
 	unsigned long offset, size;
 
-	tbl->it_busno  = bussubno;
 	of_parse_dma_window(dn, dma_window, &tbl->it_index, &offset, &size);
 
+	tbl->it_busno = phb->bus->number;
 	tbl->it_base   = 0;
 	tbl->it_blocksize  = 16;
 	tbl->it_type = TCE_PCI;
@@ -450,14 +449,10 @@ static void pci_dma_bus_setup_pSeriesLP(struct pci_bus *bus)
 	if (!ppci->iommu_table) {
 		tbl = kzalloc_node(sizeof(struct iommu_table), GFP_KERNEL,
 				   ppci->phb->node);
-		iommu_table_setparms_lpar(ppci->phb, pdn, tbl, dma_window,
-			bus->number);
+		iommu_table_setparms_lpar(ppci->phb, pdn, tbl, dma_window);
 		ppci->iommu_table = iommu_init_table(tbl, ppci->phb->node);
 		pr_debug("  created table: %p\n", ppci->iommu_table);
 	}
-
-	if (pdn != dn)
-		PCI_DN(dn)->iommu_table = ppci->iommu_table;
 }
 
 
@@ -533,21 +528,11 @@ static void pci_dma_dev_setup_pSeriesLP(struct pci_dev *dev)
 	}
 	pr_debug("  parent is %s\n", pdn->full_name);
 
-	/* Check for parent == NULL so we don't try to setup the empty EADS
-	 * slots on POWER4 machines.
-	 */
-	if (dma_window == NULL || pdn->parent == NULL) {
-		pr_debug("  no dma window for device, linking to parent\n");
-		set_iommu_table_base(&dev->dev, PCI_DN(pdn)->iommu_table);
-		return;
-	}
-
 	pci = PCI_DN(pdn);
 	if (!pci->iommu_table) {
 		tbl = kzalloc_node(sizeof(struct iommu_table), GFP_KERNEL,
 				   pci->phb->node);
-		iommu_table_setparms_lpar(pci->phb, pdn, tbl, dma_window,
-			pci->phb->bus->number);
+		iommu_table_setparms_lpar(pci->phb, pdn, tbl, dma_window);
 		pci->iommu_table = iommu_init_table(tbl, pci->phb->node);
 		pr_debug("  created table: %p\n", pci->iommu_table);
 	} else {
@@ -571,8 +556,7 @@ static int iommu_reconfig_notifier(struct notifier_block *nb, unsigned long acti
 
 	switch (action) {
 	case PSERIES_RECONFIG_REMOVE:
-		if (pci && pci->iommu_table &&
-		    of_get_property(np, "ibm,dma-window", NULL))
+		if (pci && pci->iommu_table)
 			iommu_free_table(pci->iommu_table, np->full_name);
 		break;
 	default:
@@ -589,13 +573,8 @@ static struct notifier_block iommu_reconfig_nb = {
 /* These are called very early. */
 void iommu_init_early_pSeries(void)
 {
-	if (of_chosen && of_get_property(of_chosen, "linux,iommu-off", NULL)) {
-		/* Direct I/O, IOMMU off */
-		ppc_md.pci_dma_dev_setup = NULL;
-		ppc_md.pci_dma_bus_setup = NULL;
-		set_pci_dma_ops(&dma_direct_ops);
+	if (of_chosen && of_get_property(of_chosen, "linux,iommu-off", NULL))
 		return;
-	}
 
 	if (firmware_has_feature(FW_FEATURE_LPAR)) {
 		if (firmware_has_feature(FW_FEATURE_MULTITCE)) {
@@ -622,3 +601,17 @@ void iommu_init_early_pSeries(void)
 	set_pci_dma_ops(&dma_iommu_ops);
 }
 
+static int __init disable_multitce(char *str)
+{
+	if (strcmp(str, "off") == 0 &&
+	    firmware_has_feature(FW_FEATURE_LPAR) &&
+	    firmware_has_feature(FW_FEATURE_MULTITCE)) {
+		printk(KERN_INFO "Disabling MULTITCE firmware feature\n");
+		ppc_md.tce_build = tce_build_pSeriesLP;
+		ppc_md.tce_free	 = tce_free_pSeriesLP;
+		powerpc_firmware_features &= ~FW_FEATURE_MULTITCE;
+	}
+	return 1;
+}
+
+__setup("multitce=", disable_multitce);
diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c
index f129040d974..5d3ea9f60dd 100644
--- a/arch/powerpc/platforms/pseries/lpar.c
+++ b/arch/powerpc/platforms/pseries/lpar.c
@@ -627,6 +627,18 @@ static void pSeries_lpar_flush_hash_range(unsigned long number, int local)
 		spin_unlock_irqrestore(&pSeries_lpar_tlbie_lock, flags);
 }
 
+static int __init disable_bulk_remove(char *str)
+{
+	if (strcmp(str, "off") == 0 &&
+	    firmware_has_feature(FW_FEATURE_BULK_REMOVE)) {
+			printk(KERN_INFO "Disabling BULK_REMOVE firmware feature");
+			powerpc_firmware_features &= ~FW_FEATURE_BULK_REMOVE;
+	}
+	return 1;
+}
+
+__setup("bulk_remove=", disable_bulk_remove);
+
 void __init hpte_init_lpar(void)
 {
 	ppc_md.hpte_invalidate	= pSeries_lpar_hpte_invalidate;
diff --git a/arch/powerpc/platforms/pseries/nvram.c b/arch/powerpc/platforms/pseries/nvram.c
index bc3c7f2abd7..7e828ba29bc 100644
--- a/arch/powerpc/platforms/pseries/nvram.c
+++ b/arch/powerpc/platforms/pseries/nvram.c
@@ -22,11 +22,25 @@
 #include <asm/prom.h>
 #include <asm/machdep.h>
 
+/* Max bytes to read/write in one go */
+#define NVRW_CNT 0x20
+
 static unsigned int nvram_size;
 static int nvram_fetch, nvram_store;
 static char nvram_buf[NVRW_CNT];	/* assume this is in the first 4GB */
 static DEFINE_SPINLOCK(nvram_lock);
 
+static long nvram_error_log_index = -1;
+static long nvram_error_log_size = 0;
+
+struct err_log_info {
+	int error_type;
+	unsigned int seq_num;
+};
+#define NVRAM_MAX_REQ		2079
+#define NVRAM_MIN_REQ		1055
+
+#define NVRAM_LOG_PART_NAME	"ibm,rtas-log"
 
 static ssize_t pSeries_nvram_read(char *buf, size_t count, loff_t *index)
 {
@@ -119,6 +133,197 @@ static ssize_t pSeries_nvram_get_size(void)
 	return nvram_size ? nvram_size : -ENODEV;
 }
 
+
+/* nvram_write_error_log
+ *
+ * We need to buffer the error logs into nvram to ensure that we have
+ * the failure information to decode.  If we have a severe error there
+ * is no way to guarantee that the OS or the machine is in a state to
+ * get back to user land and write the error to disk.  For example if
+ * the SCSI device driver causes a Machine Check by writing to a bad
+ * IO address, there is no way of guaranteeing that the device driver
+ * is in any state that is would also be able to write the error data
+ * captured to disk, thus we buffer it in NVRAM for analysis on the
+ * next boot.
+ *
+ * In NVRAM the partition containing the error log buffer will looks like:
+ * Header (in bytes):
+ * +-----------+----------+--------+------------+------------------+
+ * | signature | checksum | length | name       | data             |
+ * |0          |1         |2      3|4         15|16        length-1|
+ * +-----------+----------+--------+------------+------------------+
+ *
+ * The 'data' section would look like (in bytes):
+ * +--------------+------------+-----------------------------------+
+ * | event_logged | sequence # | error log                         |
+ * |0            3|4          7|8            nvram_error_log_size-1|
+ * +--------------+------------+-----------------------------------+
+ *
+ * event_logged: 0 if event has not been logged to syslog, 1 if it has
+ * sequence #: The unique sequence # for each event. (until it wraps)
+ * error log: The error log from event_scan
+ */
+int nvram_write_error_log(char * buff, int length,
+                          unsigned int err_type, unsigned int error_log_cnt)
+{
+	int rc;
+	loff_t tmp_index;
+	struct err_log_info info;
+	
+	if (nvram_error_log_index == -1) {
+		return -ESPIPE;
+	}
+
+	if (length > nvram_error_log_size) {
+		length = nvram_error_log_size;
+	}
+
+	info.error_type = err_type;
+	info.seq_num = error_log_cnt;
+
+	tmp_index = nvram_error_log_index;
+
+	rc = ppc_md.nvram_write((char *)&info, sizeof(struct err_log_info), &tmp_index);
+	if (rc <= 0) {
+		printk(KERN_ERR "nvram_write_error_log: Failed nvram_write (%d)\n", rc);
+		return rc;
+	}
+
+	rc = ppc_md.nvram_write(buff, length, &tmp_index);
+	if (rc <= 0) {
+		printk(KERN_ERR "nvram_write_error_log: Failed nvram_write (%d)\n", rc);
+		return rc;
+	}
+	
+	return 0;
+}
+
+/* nvram_read_error_log
+ *
+ * Reads nvram for error log for at most 'length'
+ */
+int nvram_read_error_log(char * buff, int length,
+                         unsigned int * err_type, unsigned int * error_log_cnt)
+{
+	int rc;
+	loff_t tmp_index;
+	struct err_log_info info;
+	
+	if (nvram_error_log_index == -1)
+		return -1;
+
+	if (length > nvram_error_log_size)
+		length = nvram_error_log_size;
+
+	tmp_index = nvram_error_log_index;
+
+	rc = ppc_md.nvram_read((char *)&info, sizeof(struct err_log_info), &tmp_index);
+	if (rc <= 0) {
+		printk(KERN_ERR "nvram_read_error_log: Failed nvram_read (%d)\n", rc);
+		return rc;
+	}
+
+	rc = ppc_md.nvram_read(buff, length, &tmp_index);
+	if (rc <= 0) {
+		printk(KERN_ERR "nvram_read_error_log: Failed nvram_read (%d)\n", rc);
+		return rc;
+	}
+
+	*error_log_cnt = info.seq_num;
+	*err_type = info.error_type;
+
+	return 0;
+}
+
+/* This doesn't actually zero anything, but it sets the event_logged
+ * word to tell that this event is safely in syslog.
+ */
+int nvram_clear_error_log(void)
+{
+	loff_t tmp_index;
+	int clear_word = ERR_FLAG_ALREADY_LOGGED;
+	int rc;
+
+	if (nvram_error_log_index == -1)
+		return -1;
+
+	tmp_index = nvram_error_log_index;
+	
+	rc = ppc_md.nvram_write((char *)&clear_word, sizeof(int), &tmp_index);
+	if (rc <= 0) {
+		printk(KERN_ERR "nvram_clear_error_log: Failed nvram_write (%d)\n", rc);
+		return rc;
+	}
+
+	return 0;
+}
+
+/* pseries_nvram_init_log_partition
+ *
+ * This will setup the partition we need for buffering the
+ * error logs and cleanup partitions if needed.
+ *
+ * The general strategy is the following:
+ * 1.) If there is log partition large enough then use it.
+ * 2.) If there is none large enough, search
+ * for a free partition that is large enough.
+ * 3.) If there is not a free partition large enough remove 
+ * _all_ OS partitions and consolidate the space.
+ * 4.) Will first try getting a chunk that will satisfy the maximum
+ * error log size (NVRAM_MAX_REQ).
+ * 5.) If the max chunk cannot be allocated then try finding a chunk
+ * that will satisfy the minum needed (NVRAM_MIN_REQ).
+ */
+static int __init pseries_nvram_init_log_partition(void)
+{
+	loff_t p;
+	int size;
+
+	/* Scan nvram for partitions */
+	nvram_scan_partitions();
+
+	/* Lookg for ours */
+	p = nvram_find_partition(NVRAM_LOG_PART_NAME, NVRAM_SIG_OS, &size);
+
+	/* Found one but too small, remove it */
+	if (p && size < NVRAM_MIN_REQ) {
+		pr_info("nvram: Found too small "NVRAM_LOG_PART_NAME" partition"
+			",removing it...");
+		nvram_remove_partition(NVRAM_LOG_PART_NAME, NVRAM_SIG_OS);
+		p = 0;
+	}
+
+	/* Create one if we didn't find */
+	if (!p) {
+		p = nvram_create_partition(NVRAM_LOG_PART_NAME, NVRAM_SIG_OS,
+					   NVRAM_MAX_REQ, NVRAM_MIN_REQ);
+		/* No room for it, try to get rid of any OS partition
+		 * and try again
+		 */
+		if (p == -ENOSPC) {
+			pr_info("nvram: No room to create "NVRAM_LOG_PART_NAME
+				" partition, deleting all OS partitions...");
+			nvram_remove_partition(NULL, NVRAM_SIG_OS);
+			p = nvram_create_partition(NVRAM_LOG_PART_NAME,
+						   NVRAM_SIG_OS, NVRAM_MAX_REQ,
+						   NVRAM_MIN_REQ);
+		}
+	}
+
+	if (p <= 0) {
+		pr_err("nvram: Failed to find or create "NVRAM_LOG_PART_NAME
+		       " partition, err %d\n", (int)p);
+		return 0;
+	}
+
+	nvram_error_log_index = p;
+	nvram_error_log_size = nvram_get_partition_size(p) -
+		sizeof(struct err_log_info);
+	
+	return 0;
+}
+machine_arch_initcall(pseries, pseries_nvram_init_log_partition);
+
 int __init pSeries_nvram_init(void)
 {
 	struct device_node *nvram;
diff --git a/arch/powerpc/platforms/pseries/pseries_energy.c b/arch/powerpc/platforms/pseries/pseries_energy.c
new file mode 100644
index 00000000000..c8b3c69fe89
--- /dev/null
+++ b/arch/powerpc/platforms/pseries/pseries_energy.c
@@ -0,0 +1,326 @@
+/*
+ * POWER platform energy management driver
+ * Copyright (C) 2010 IBM Corporation
+ *
+ * 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.
+ *
+ * This pseries platform device driver provides access to
+ * platform energy management capabilities.
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/seq_file.h>
+#include <linux/sysdev.h>
+#include <linux/cpu.h>
+#include <linux/of.h>
+#include <asm/cputhreads.h>
+#include <asm/page.h>
+#include <asm/hvcall.h>
+
+
+#define MODULE_VERS "1.0"
+#define MODULE_NAME "pseries_energy"
+
+/* Driver flags */
+
+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)
+{
+	struct device_node *dn = NULL;
+	const int *indexes;
+	int i;
+	int rc = 1;
+	u32 ret = 0;
+
+	dn = of_find_node_by_path("/cpus");
+	if (dn == NULL)
+		goto err;
+	indexes = of_get_property(dn, "ibm,drc-indexes", NULL);
+	if (indexes == NULL)
+		goto err_of_node_put;
+	/* Convert logical cpu number to core number */
+	i = cpu_core_index_of_thread(cpu);
+	/*
+	 * The first element indexes[0] is the number of drc_indexes
+	 * returned in the list.  Hence i+1 will get the drc_index
+	 * corresponding to core number i.
+	 */
+	WARN_ON(i > indexes[0]);
+	ret = indexes[i + 1];
+	rc = 0;
+
+err_of_node_put:
+	of_node_put(dn);
+err:
+	if (rc)
+		printk(KERN_WARNING "cpu_to_drc_index(%d) failed", cpu);
+	return ret;
+}
+
+static int drc_index_to_cpu(u32 drc_index)
+{
+	struct device_node *dn = NULL;
+	const int *indexes;
+	int i, cpu = 0;
+	int rc = 1;
+
+	dn = of_find_node_by_path("/cpus");
+	if (dn == NULL)
+		goto err;
+	indexes = of_get_property(dn, "ibm,drc-indexes", NULL);
+	if (indexes == NULL)
+		goto err_of_node_put;
+	/*
+	 * First element in the array is the number of drc_indexes
+	 * returned.  Search through the list to find the matching
+	 * drc_index and get the core number
+	 */
+	for (i = 0; i < indexes[0]; i++) {
+		if (indexes[i + 1] == drc_index)
+			break;
+	}
+	/* Convert core number to logical cpu number */
+	cpu = cpu_first_thread_of_core(i);
+	rc = 0;
+
+err_of_node_put:
+	of_node_put(dn);
+err:
+	if (rc)
+		printk(KERN_WARNING "drc_index_to_cpu(%d) failed", drc_index);
+	return cpu;
+}
+
+/*
+ * pseries hypervisor call H_BEST_ENERGY provides hints to OS on
+ * preferred logical cpus to activate or deactivate for optimized
+ * energy consumption.
+ */
+
+#define FLAGS_MODE1	0x004E200000080E01
+#define FLAGS_MODE2	0x004E200000080401
+#define FLAGS_ACTIVATE  0x100
+
+static ssize_t get_best_energy_list(char *page, int activate)
+{
+	int rc, cnt, i, cpu;
+	unsigned long retbuf[PLPAR_HCALL9_BUFSIZE];
+	unsigned long flags = 0;
+	u32 *buf_page;
+	char *s = page;
+
+	buf_page = (u32 *) get_zeroed_page(GFP_KERNEL);
+	if (!buf_page)
+		return -ENOMEM;
+
+	flags = FLAGS_MODE1;
+	if (activate)
+		flags |= FLAGS_ACTIVATE;
+
+	rc = plpar_hcall9(H_BEST_ENERGY, retbuf, flags, 0, __pa(buf_page),
+				0, 0, 0, 0, 0, 0);
+	if (rc != H_SUCCESS) {
+		free_page((unsigned long) buf_page);
+		return -EINVAL;
+	}
+
+	cnt = retbuf[0];
+	for (i = 0; i < cnt; i++) {
+		cpu = drc_index_to_cpu(buf_page[2*i+1]);
+		if ((cpu_online(cpu) && !activate) ||
+		    (!cpu_online(cpu) && activate))
+			s += sprintf(s, "%d,", cpu);
+	}
+	if (s > page) { /* Something to show */
+		s--; /* Suppress last comma */
+		s += sprintf(s, "\n");
+	}
+
+	free_page((unsigned long) buf_page);
+	return s-page;
+}
+
+static ssize_t get_best_energy_data(struct sys_device *dev,
+					char *page, int activate)
+{
+	int rc;
+	unsigned long retbuf[PLPAR_HCALL9_BUFSIZE];
+	unsigned long flags = 0;
+
+	flags = FLAGS_MODE2;
+	if (activate)
+		flags |= FLAGS_ACTIVATE;
+
+	rc = plpar_hcall9(H_BEST_ENERGY, retbuf, flags,
+				cpu_to_drc_index(dev->id),
+				0, 0, 0, 0, 0, 0, 0);
+
+	if (rc != H_SUCCESS)
+		return -EINVAL;
+
+	return sprintf(page, "%lu\n", retbuf[1] >> 32);
+}
+
+/* Wrapper functions */
+
+static ssize_t cpu_activate_hint_list_show(struct sysdev_class *class,
+			struct sysdev_class_attribute *attr, char *page)
+{
+	return get_best_energy_list(page, 1);
+}
+
+static ssize_t cpu_deactivate_hint_list_show(struct sysdev_class *class,
+			struct sysdev_class_attribute *attr, char *page)
+{
+	return get_best_energy_list(page, 0);
+}
+
+static ssize_t percpu_activate_hint_show(struct sys_device *dev,
+			struct sysdev_attribute *attr, char *page)
+{
+	return get_best_energy_data(dev, page, 1);
+}
+
+static ssize_t percpu_deactivate_hint_show(struct sys_device *dev,
+			struct sysdev_attribute *attr, char *page)
+{
+	return get_best_energy_data(dev, page, 0);
+}
+
+/*
+ * Create sysfs interface:
+ * /sys/devices/system/cpu/pseries_activate_hint_list
+ * /sys/devices/system/cpu/pseries_deactivate_hint_list
+ *	Comma separated list of cpus to activate or deactivate
+ * /sys/devices/system/cpu/cpuN/pseries_activate_hint
+ * /sys/devices/system/cpu/cpuN/pseries_deactivate_hint
+ *	Per-cpu value of the hint
+ */
+
+struct sysdev_class_attribute attr_cpu_activate_hint_list =
+		_SYSDEV_CLASS_ATTR(pseries_activate_hint_list, 0444,
+		cpu_activate_hint_list_show, NULL);
+
+struct sysdev_class_attribute attr_cpu_deactivate_hint_list =
+		_SYSDEV_CLASS_ATTR(pseries_deactivate_hint_list, 0444,
+		cpu_deactivate_hint_list_show, NULL);
+
+struct sysdev_attribute attr_percpu_activate_hint =
+		_SYSDEV_ATTR(pseries_activate_hint, 0444,
+		percpu_activate_hint_show, NULL);
+
+struct sysdev_attribute attr_percpu_deactivate_hint =
+		_SYSDEV_ATTR(pseries_deactivate_hint, 0444,
+		percpu_deactivate_hint_show, NULL);
+
+static int __init pseries_energy_init(void)
+{
+	int cpu, err;
+	struct sys_device *cpu_sys_dev;
+
+	if (!check_for_h_best_energy()) {
+		printk(KERN_INFO "Hypercall H_BEST_ENERGY not supported\n");
+		return 0;
+	}
+	/* Create the sysfs files */
+	err = sysfs_create_file(&cpu_sysdev_class.kset.kobj,
+				&attr_cpu_activate_hint_list.attr);
+	if (!err)
+		err = sysfs_create_file(&cpu_sysdev_class.kset.kobj,
+				&attr_cpu_deactivate_hint_list.attr);
+
+	if (err)
+		return err;
+	for_each_possible_cpu(cpu) {
+		cpu_sys_dev = get_cpu_sysdev(cpu);
+		err = sysfs_create_file(&cpu_sys_dev->kobj,
+				&attr_percpu_activate_hint.attr);
+		if (err)
+			break;
+		err = sysfs_create_file(&cpu_sys_dev->kobj,
+				&attr_percpu_deactivate_hint.attr);
+		if (err)
+			break;
+	}
+
+	if (err)
+		return err;
+
+	sysfs_entries = 1; /* Removed entries on cleanup */
+	return 0;
+
+}
+
+static void __exit pseries_energy_cleanup(void)
+{
+	int cpu;
+	struct sys_device *cpu_sys_dev;
+
+	if (!sysfs_entries)
+		return;
+
+	/* Remove the sysfs files */
+	sysfs_remove_file(&cpu_sysdev_class.kset.kobj,
+				&attr_cpu_activate_hint_list.attr);
+
+	sysfs_remove_file(&cpu_sysdev_class.kset.kobj,
+				&attr_cpu_deactivate_hint_list.attr);
+
+	for_each_possible_cpu(cpu) {
+		cpu_sys_dev = get_cpu_sysdev(cpu);
+		sysfs_remove_file(&cpu_sys_dev->kobj,
+				&attr_percpu_activate_hint.attr);
+		sysfs_remove_file(&cpu_sys_dev->kobj,
+				&attr_percpu_deactivate_hint.attr);
+	}
+}
+
+module_init(pseries_energy_init);
+module_exit(pseries_energy_cleanup);
+MODULE_DESCRIPTION("Driver for pSeries platform energy management");
+MODULE_AUTHOR("Vaidyanathan Srinivasan");
+MODULE_LICENSE("GPL");
diff --git a/arch/powerpc/platforms/pseries/suspend.c b/arch/powerpc/platforms/pseries/suspend.c
index ed72098bb4e..a8ca289ff26 100644
--- a/arch/powerpc/platforms/pseries/suspend.c
+++ b/arch/powerpc/platforms/pseries/suspend.c
@@ -153,7 +153,7 @@ static struct sysdev_class suspend_sysdev_class = {
 	.name = "power",
 };
 
-static struct platform_suspend_ops pseries_suspend_ops = {
+static const struct platform_suspend_ops pseries_suspend_ops = {
 	.valid		= suspend_valid_only_mem,
 	.begin		= pseries_suspend_begin,
 	.prepare_late	= pseries_prepare_late,