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

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * pseries Memory Hotplug infrastructure.
 *
 * Copyright (C) 2008 Badari Pulavarty, IBM Corporation
 */

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

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_obj(*new_prop);
	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)
{
	__be32 *assoc_arrays;
	u32 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(lmb_node, "ibm,associativity", NULL);
	if (!lmb_assoc) {
		dlpar_free_cc_nodes(lmb_node);
		return -ENODEV;
	}

	update_numa_distance(lmb_node);

	dr_node = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
	if (!dr_node) {
		dlpar_free_cc_nodes(lmb_node);
		return -ENODEV;
	}

	ala_prop = of_find_property(dr_node, "ibm,associativity-lookup-arrays",
				    NULL);
	if (!ala_prop) {
		of_node_put(dr_node);
		dlpar_free_cc_nodes(lmb_node);
		return -ENODEV;
	}

	found = find_aa_index(dr_node, ala_prop, lmb_assoc, &aa_index);

	of_node_put(dr_node);
	dlpar_free_cc_nodes(lmb_node);

	if (!found) {
		pr_err("Could not find LMB associativity\n");
		return -1;
	}

	lmb->aa_index = aa_index;
	return 0;
}

static struct memory_block *lmb_to_memblock(struct drmem_lmb *lmb