/*
* 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.
*/
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/memblock.h>
#include <linux/vmalloc.h>
#include <linux/memory.h>
#include <linux/memory_hotplug.h>
#include <asm/firmware.h>
#include <asm/machdep.h>
#include <asm/prom.h>
#include <asm/sparsemem.h>
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;
}
#ifdef CONFIG_MEMORY_HOTREMOVE
static int pseries_remove_memory(u64 start, u64 size)
{
int ret;
/* Remove htab bolted mappings for this section of memory */
start = (unsigned long)__va(start);
ret = remove_section_mapping(start, start + size);
/* Ensure all vmalloc mappings are flushed in case they also
* hit that section of memory
*/
vm_unmap_aliases();
return ret;
}
static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size)
{
unsigned long block_sz, start_pfn;
int sections_per_block;
int i, nid;
start_pfn = base >> PAGE_SHIFT;
lock_device_hotplug();
if (!pfn_valid(start_pfn))
goto out;
block_sz = pseries_memory_block_size();
sections_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE;
nid = memory_add_physaddr_to_nid(base);
for (i = 0; i < sections_per_block; i++) {
remove_memory(nid, base, MIN_MEMORY_BLOCK_SIZE);
base += MIN_MEMORY_BLOCK_SIZE;
}
out:
/* Update memory regions for memory remove */
memblock_remove(base, memblock_size);
unlock_device_hotplug();
return 0;
}
static int pseries_remove_mem_node(struct device_node *np)
{
const char *type;
const unsigned int *regs;
unsigned long base;
unsigned int lmb_size;
int ret = -EINVAL;
/*
* Check to see if we are actually removing memory
*/
type = of_get_property(np, "device_type", NULL);
if (type == NULL || strcmp(type, "memory") != 0)
return 0;
/*
* Find the bae address and size of the memblock
*/
regs = of_get_property(np, "reg", NULL);
if (!regs)
return ret;
base = *(unsigned long *)regs;
lmb_size = regs[3];
pseries_remove_memblock(base, lmb_size);
return 0;
}
#else
static inline int pseries_remove_memblock(unsigned long base,
unsigned int memblock_size)
{
return -EOPNOTSUPP;
}
static inline int pseries_remove_mem_node(struct device_node *np)
{
return 0;
}
#endif /* CONFIG_MEMORY_HOTREMOVE */
static int pseries_add_mem_node(struct device_node *np)
{
const char *type;
const unsigned int *regs;
unsigned long base;
unsigned int lmb_size;
int ret = -EINVAL;
/*
* Check to see if we are actually adding memory
*/
type = of_get_property(np, "device_type", NULL);
if (type == NULL || strcmp(type, "memory") != 0)
return 0;
/*
* Find the base and size of the memblock
*/
regs = of_get_property(np, "reg", NULL);
if (!regs)
return ret;
base = *(unsigned long *)regs;
lmb_size = regs[3];
/*
* Update memory region to represent the memory add
*/
ret = memblock_add(base, lmb_size);
return (ret < 0) ? -EINVAL : 0;
}
static int pseries_update_drconf_memory(struct of_prop_reconfig *pr)
{
struct of_drconf_cell *new_drmem, *old_drmem;
unsigned long memblock_size;
u32 entries;
u32 *p;
int i, rc = -EINVAL;
memblock_size = pseries_memory_block_size();
if (!memblock_size)
return -EINVAL;
p = (u32 *) pr->old_prop->value;
if (!p)
return -EINVAL;
/* The first int of the property is the number of lmb's described
* by the property. This is followed by an array of of_drconf_cell
* entries. Get the niumber of entries and skip to the array of
* of_drconf_cell's.
*/
entries = *p++;
old_drmem = (struct of_drconf_cell *)p;
p = (u32 *)pr->prop->value;
p++;
new_drmem = (struct of_drconf_cell *)p;
for (i = 0; i < entries; i++) {
if ((old_drmem[i].flags & DRCONF_MEM_ASSIGNED) &&
(!(new_drmem[i].flags & DRCONF_MEM_ASSIGNED))) {
rc = pseries_remove_memblock(old_drmem[i].base_addr,
memblock_size);
break;
} else if ((!(old_drmem[i].flags & DRCONF_MEM_ASSIGNED)) &&
(new_drmem[i].flags & DRCONF_MEM_ASSIGNED)) {
rc = memblock_add(old_drmem[i].base_addr,
memblock_size);
rc = (rc < 0) ? -EINVAL : 0;
break;
}
}
return rc;
}
static int pseries_memory_notifier(struct notifier_block *nb,
unsigned long action, void *node)
{
struct of_prop_reconfig *pr;
int err = 0;
switch (action) {
case OF_RECONFIG_ATTACH_NODE:
err = pseries_add_mem_node(node);
break;
case OF_RECONFIG_DETACH_NODE:
err = pseries_remove_mem_node(node);
break;
case OF_RECONFIG_UPDATE_PROPERTY:
pr = (struct of_prop_reconfig *)node;
if (!strcmp(pr->prop->name, "ibm,dynamic-memory"))
err = pseries_update_drconf_memory(pr);
break;
}
return notifier_from_errno(err);
}
static struct notifier_block pseries_mem_nb = {
.notifier_call = pseries_memory_notifier,
};
static int __init pseries_memory_hotplug_init(void)
{
if (firmware_has_feature(FW_FEATURE_LPAR))
of_reconfig_notifier_register(&pseries_mem_nb);
#ifdef CONFIG_MEMORY_HOTREMOVE
ppc_md.remove_memory = pseries_remove_memory;
#endif
return 0;
}
machine_device_initcall(pseries, pseries_memory_hotplug_init);
