path: root/arch/powerpc/platforms/pseries/hotplug-memory.c

/*
 * pseries Memory Hotplug infrastructure.
 *
 * Copyright (C) 2008 Badari Pulavarty, 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.
 */

#define pr_fmt(fmt)	"pseries-hotplug-mem: " fmt

#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/memblock.h>
#include <linux/memory.h>
#include <linux/memory_hotplug.h>
#include <linux/slab.h>

#include <asm/firmware.h>
#include <asm/machdep.h>
#include <asm/prom.h>
#include <asm/sparsemem.h>
#include <asm/fadump.h>
#include <asm/drmem.h>
#include "pseries.h"

static bool rtas_hp_event;

unsigned long pseries_memory_block_size(void)
{
	struct device_node *np;
	unsigned int memblock_size = MIN_MEMORY_BLOCK_SIZE;
	struct resource r;

	np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
	if (np) {
		const __be64 *size;

		size = of_get_property(np, "ibm,lmb-size", NULL);
		if (size)
			memblock_size = be64_to_cpup(size);
		of_node_put(np);
	} else  if (machine_is(pseries)) {
		/* This fallback really only applies to pseries */
		unsigned int memzero_size = 0;

		np = of_find_node_by_path("/memory@0");
		if (np) {
			if (!of_address_to_resource(np, 0, &r))
				memzero_size = resource_size(&r);
			of_node_put(np);
		}

		if (memzero_size) {
			/* We now know the size of memory@0, use this to find
			 * the first memoryblock and get its size.
			 */
			char buf[64];

			sprintf(buf, "/memory@%x", memzero_size);
			np = of_find_node_by_path(buf);
			if (np) {
				if (!of_address_to_resource(np, 0, &r))
					memblock_size = resource_size(&r);
				of_node_put(np);
			}
		}
	}
	return memblock_size;
}

static void dlpar_free_property(struct property *prop)
{
	kfree(prop->name);
	kfree(prop->value);
	kfree(prop);
}

static struct property *dlpar_clone_property(struct property *prop,
					     u32 prop_size)
{
	struct property *new_prop;

	new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
	if (!new_prop)
		return NULL;

	new_prop->name = kstrdup(prop->name, GFP_KERNEL);
	new_prop->value = kzalloc(prop_size, GFP_KERNEL);
	if (!new_prop->name || !new_prop->value) {
		dlpar_free_property(new_prop);
		return NULL;
	}

	memcpy(new_prop->value, prop->value, prop->length);
	new_prop->length = prop_size;

	of_property_set_flag(new_prop, OF_DYNAMIC);
	return new_prop;
}

static bool find_aa_index(struct device_node *dr_node,
			 struct property *ala_prop,
			 const u32 *lmb_assoc, u32 *aa_index)
{
	u32 *assoc_arrays, new_prop_size;
	struct property *new_prop;
	int aa_arrays, aa_array_entries, aa_array_sz;
	int i, index;

	/*
	 * The ibm,associativity-lookup-arrays property is defined to be
	 * a 32-bit value specifying the number of associativity arrays
	 * followed by a 32-bitvalue specifying the number of entries per
	 * array, followed by the associativity arrays.
	 */
	assoc_arrays = ala_prop->value;

	aa_arrays = be32_to_cpu(assoc_arrays[0]);
	aa_array_entries = be32_to_cpu(assoc_arrays[1]);
	aa_array_sz = aa_array_entries * sizeof(u32);

	for (i = 0; i < aa_arrays; i++) {
		index = (i * aa_array_entries) + 2;

		if (memcmp(&assoc_arrays[index], &lmb_assoc[1], aa_array_sz))
			continue;

		*aa_index = i;
		return true;
	}

	new_prop_size = ala_prop->length + aa_array_sz;
	new_prop = dlpar_clone_property(ala_prop, new_prop_size);
	if (!new_prop)
		return false;

	assoc_arrays = new_prop->value;

	/* increment the number of entries in the lookup array */
	assoc_arrays[0] = cpu_to_be32(aa_arrays + 1);

	/* copy the new associativity into the lookup array */
	index = aa_arrays * aa_array_entries + 2;
	memcpy(&assoc_arrays[index], &lmb_assoc[1], aa_array_sz);

	of_update_property(dr_node, new_prop);

	/*
	 * The associativity lookup array index for this lmb is
	 * number of entries - 1 since we added its associativity
	 * to the end of the lookup array.
	 */
	*aa_index = be32_to_cpu(assoc_arrays[0]) - 1;
	return true;
}

static int update_lmb_associativity_index(struct drmem_lmb *lmb)
{
	struct device_node *parent, *lmb_node, *dr_node;
	struct property *ala_prop;
	const u32 *lmb_assoc;
	u32 aa_index;
	bool found;

	parent = of_find_node_by_path("/");
	if (!parent)
		return -ENODEV;

	lmb_node = dlpar_configure_connector(cpu_to_be32(lmb->drc_index),
					     parent);
	of_node_put(parent);
	if (!lmb_node)
		return -EINVAL;

	lmb_assoc = of_get_property