Commit ab519a01 authored by Nathan Fontenot's avatar Nathan Fontenot Committed by Benjamin Herrenschmidt
Browse files

powerpc/pseries: Kernel DLPAR Infrastructure 



The Dynamic Logical Partitioning capabilities of the powerpc pseries platform
allows for the addition and removal of resources (i.e. CPU's, memory, and PCI
devices) from a partition. The removal of a resource involves
removing the resource's node from the device tree and then returning the
resource to firmware via the rtas set-indicator call.  To add a resource, it
is first obtained from firmware via the rtas set-indicator call and then a
new device tree node is created using the ibm,configure-coinnector rtas call
and added to the device tree.

This patch provides the kernel DLPAR infrastructure in a new filed named
dlpar.c.  The functionality provided is for acquiring and releasing a resource
from firmware and the parsing of information returned from the
ibm,configure-connector rtas call.  Additionally this exports the pSeries
reconfiguration notifier chain so that it can be invoked when device tree
updates are made.

Signed-off-by: default avatarNathan Fontenot <nfont@austin.ibm.com>
Acked-by: default avatarPaul Mackerras <paulus@samba.org>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
parent 1496e89a

arch/powerpc/include/asm/pSeries_reconfig.h

+1 −0
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ 
#ifdef CONFIG_PPC_PSERIES

extern int pSeries_reconfig_notifier_register(struct notifier_block *);

extern void pSeries_reconfig_notifier_unregister(struct notifier_block *);

extern struct blocking_notifier_head pSeries_reconfig_chain;

#else /* !CONFIG_PPC_PSERIES */

static inline int pSeries_reconfig_notifier_register(struct notifier_block *nb)

{

arch/powerpc/platforms/pseries/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -8,7 +8,7 @@ endif 


obj-y			:= lpar.o hvCall.o nvram.o reconfig.o \

			   setup.o iommu.o ras.o \

			   firmware.o power.o

			   firmware.o power.o dlpar.o

obj-$(CONFIG_SMP)	+= smp.o

obj-$(CONFIG_XICS)	+= xics.o

obj-$(CONFIG_SCANLOG)	+= scanlog.o

arch/powerpc/platforms/pseries/dlpar.c

0 → 100644
+344 −0
Original line number Diff line number Diff line 
/*

 * Support for dynamic reconfiguration for PCI, Memory, and CPU

 * Hotplug and Dynamic Logical Partitioning on RPA platforms.

 *

 * Copyright (C) 2009 Nathan Fontenot

 * Copyright (C) 2009 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.

 */



#include <linux/kernel.h>

#include <linux/kref.h>

#include <linux/notifier.h>

#include <linux/proc_fs.h>

#include <linux/spinlock.h>

#include <linux/cpu.h>



#include <asm/prom.h>

#include <asm/machdep.h>

#include <asm/uaccess.h>

#include <asm/rtas.h>

#include <asm/pSeries_reconfig.h>



struct cc_workarea {

	u32	drc_index;

	u32	zero;

	u32	name_offset;

	u32	prop_length;

	u32	prop_offset;

};



static void dlpar_free_cc_property(struct property *prop)

{

	kfree(prop->name);

	kfree(prop->value);

	kfree(prop);

}



static struct property *dlpar_parse_cc_property(struct cc_workarea *ccwa)

{

	struct property *prop;

	char *name;

	char *value;



	prop = kzalloc(sizeof(*prop), GFP_KERNEL);

	if (!prop)

		return NULL;



	name = (char *)ccwa + ccwa->name_offset;

	prop->name = kstrdup(name, GFP_KERNEL);



	prop->length = ccwa->prop_length;

	value = (char *)ccwa + ccwa->prop_offset;

	prop->value = kzalloc(prop->length, GFP_KERNEL);

	if (!prop->value) {

		dlpar_free_cc_property(prop);

		return NULL;

	}



	memcpy(prop->value, value, prop->length);

	return prop;

}



static struct device_node *dlpar_parse_cc_node(struct cc_workarea *ccwa)

{

	struct device_node *dn;

	char *name;



	dn = kzalloc(sizeof(*dn), GFP_KERNEL);

	if (!dn)

		return NULL;



	/* The configure connector reported name does not contain a

	 * preceeding '/', so we allocate a buffer large enough to

	 * prepend this to the full_name.

	 */

	name = (char *)ccwa + ccwa->name_offset;

	dn->full_name = kmalloc(strlen(name) + 2, GFP_KERNEL);

	if (!dn->full_name) {

		kfree(dn);

		return NULL;

	}



	sprintf(dn->full_name, "/%s", name);

	return dn;

}



static void dlpar_free_one_cc_node(struct device_node *dn)

{

	struct property *prop;



	while (dn->properties) {

		prop = dn->properties;

		dn->properties = prop->next;

		dlpar_free_cc_property(prop);

	}



	kfree(dn->full_name);

	kfree(dn);

}



static void dlpar_free_cc_nodes(struct device_node *dn)

{

	if (dn->child)

		dlpar_free_cc_nodes(dn->child);



	if (dn->sibling)

		dlpar_free_cc_nodes(dn->sibling);



	dlpar_free_one_cc_node(dn);

}



#define NEXT_SIBLING    1

#define NEXT_CHILD      2

#define NEXT_PROPERTY   3

#define PREV_PARENT     4

#define MORE_MEMORY     5

#define CALL_AGAIN	-2

#define ERR_CFG_USE     -9003



struct device_node *dlpar_configure_connector(u32 drc_index)

{

	struct device_node *dn;

	struct device_node *first_dn = NULL;

	struct device_node *last_dn = NULL;

	struct property *property;

	struct property *last_property = NULL;

	struct cc_workarea *ccwa;

	int cc_token;

	int rc;



	cc_token = rtas_token("ibm,configure-connector");

	if (cc_token == RTAS_UNKNOWN_SERVICE)

		return NULL;



	spin_lock(&rtas_data_buf_lock);

	ccwa = (struct cc_workarea *)&rtas_data_buf[0];

	ccwa->drc_index = drc_index;

	ccwa->zero = 0;



	rc = rtas_call(cc_token, 2, 1, NULL, rtas_data_buf, NULL);

	while (rc) {

		switch (rc) {

		case NEXT_SIBLING:

			dn = dlpar_parse_cc_node(ccwa);

			if (!dn)

				goto cc_error;



			dn->parent = last_dn->parent;

			last_dn->sibling = dn;

			last_dn = dn;

			break;



		case NEXT_CHILD:

			dn = dlpar_parse_cc_node(ccwa);

			if (!dn)

				goto cc_error;



			if (!first_dn)

				first_dn = dn;

			else {

				dn->parent = last_dn;

				if (last_dn)

					last_dn->child = dn;

			}



			last_dn = dn;

			break;



		case NEXT_PROPERTY:

			property = dlpar_parse_cc_property(ccwa);

			if (!property)

				goto cc_error;



			if (!last_dn->properties)

				last_dn->properties = property;

			else

				last_property->next = property;



			last_property = property;

			break;



		case PREV_PARENT:

			last_dn = last_dn->parent;

			break;



		case CALL_AGAIN:

			break;



		case MORE_MEMORY:

		case ERR_CFG_USE:

		default:

			printk(KERN_ERR "Unexpected Error (%d) "

			       "returned from configure-connector\n", rc);

			goto cc_error;

		}



		rc = rtas_call(cc_token, 2, 1, NULL, rtas_data_buf, NULL);

	}



	spin_unlock(&rtas_data_buf_lock);

	return first_dn;



cc_error:

	if (first_dn)

		dlpar_free_cc_nodes(first_dn);

	spin_unlock(&rtas_data_buf_lock);

	return NULL;

}



static struct device_node *derive_parent(const char *path)

{

	struct device_node *parent;

	char *last_slash;



	last_slash = strrchr(path, '/');

	if (last_slash == path) {

		parent = of_find_node_by_path("/");

	} else {

		char *parent_path;

		int parent_path_len = last_slash - path + 1;

		parent_path = kmalloc(parent_path_len, GFP_KERNEL);

		if (!parent_path)

			return NULL;



		strlcpy(parent_path, path, parent_path_len);

		parent = of_find_node_by_path(parent_path);

		kfree(parent_path);

	}



	return parent;

}



int dlpar_attach_node(struct device_node *dn)

{

	struct proc_dir_entry *ent;

	int rc;



	of_node_set_flag(dn, OF_DYNAMIC);

	kref_init(&dn->kref);

	dn->parent = derive_parent(dn->full_name);

	if (!dn->parent)

		return -ENOMEM;



	rc = blocking_notifier_call_chain(&pSeries_reconfig_chain,

					  PSERIES_RECONFIG_ADD, dn);

	if (rc == NOTIFY_BAD) {

		printk(KERN_ERR "Failed to add device node %s\n",

		       dn->full_name);

		return -ENOMEM; /* For now, safe to assume kmalloc failure */

	}



	of_attach_node(dn);



#ifdef CONFIG_PROC_DEVICETREE

	ent = proc_mkdir(strrchr(dn->full_name, '/') + 1, dn->parent->pde);

	if (ent)

		proc_device_tree_add_node(dn, ent);

#endif



	of_node_put(dn->parent);

	return 0;

}



int dlpar_detach_node(struct device_node *dn)

{

	struct device_node *parent = dn->parent;

	struct property *prop = dn->properties;



#ifdef CONFIG_PROC_DEVICETREE

	while (prop) {

		remove_proc_entry(prop->name, dn->pde);

		prop = prop->next;

	}



	if (dn->pde)

		remove_proc_entry(dn->pde->name, parent->pde);

#endif



	blocking_notifier_call_chain(&pSeries_reconfig_chain,

			    PSERIES_RECONFIG_REMOVE, dn);

	of_detach_node(dn);

	of_node_put(dn); /* Must decrement the refcount */



	return 0;

}



#define DR_ENTITY_SENSE		9003

#define DR_ENTITY_PRESENT	1

#define DR_ENTITY_UNUSABLE	2

#define ALLOCATION_STATE	9003

#define ALLOC_UNUSABLE		0

#define ALLOC_USABLE		1

#define ISOLATION_STATE		9001

#define ISOLATE			0

#define UNISOLATE		1



int dlpar_acquire_drc(u32 drc_index)

{

	int dr_status, rc;



	rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,

		       DR_ENTITY_SENSE, drc_index);

	if (rc || dr_status != DR_ENTITY_UNUSABLE)

		return -1;



	rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_USABLE);

	if (rc)

		return rc;



	rc = rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);

	if (rc) {

		rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);

		return rc;

	}



	return 0;

}



int dlpar_release_drc(u32 drc_index)

{

	int dr_status, rc;



	rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,

		       DR_ENTITY_SENSE, drc_index);

	if (rc || dr_status != DR_ENTITY_PRESENT)

		return -1;



	rc = rtas_set_indicator(ISOLATION_STATE, drc_index, ISOLATE);

	if (rc)

		return rc;



	rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);

	if (rc) {

		rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);

		return rc;

	}



	return 0;

}

arch/powerpc/platforms/pseries/reconfig.c

+1 −1
Original line number Diff line number Diff line
@@ -96,7 +96,7 @@ static struct device_node *derive_parent(const char *path) 
	return parent;

}



static BLOCKING_NOTIFIER_HEAD(pSeries_reconfig_chain);

BLOCKING_NOTIFIER_HEAD(pSeries_reconfig_chain);



int pSeries_reconfig_notifier_register(struct notifier_block *nb)

{

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