[GitHub/mt8127/android_kernel_alcatel_ttab.git] / 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.
 */

#include <linux/of.h>
#include <linux/memblock.h>
#include <linux/vmalloc.h>
#include <linux/memory.h>

#include <asm/firmware.h>
#include <asm/machdep.h>
#include <asm/sparsemem.h>

static unsigned long get_memblock_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;
}

/* WARNING: This is going to override the generic definition whenever
 * pseries is built-in regardless of what platform is active at boot
 * time. This is fine for now as this is the only "option" and it
 * should work everywhere. If not, we'll have to turn this into a
 * ppc_md. callback
 */
unsigned long memory_block_size_bytes(void)
{
	return get_memblock_size();
}

#ifdef CONFIG_MEMORY_HOTREMOVE
static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size)
{
	unsigned long start, start_pfn;
	struct zone *zone;
	int ret;
	unsigned long section;
	unsigned long sections_to_remove;

	start_pfn = base >> PAGE_SHIFT;

	if (!pfn_valid(start_pfn)) {
		memblock_remove(base, memblock_size);
		return 0;
	}

	zone = page_zone(pfn_to_page(start_pfn));

	/*
	 * Remove section mappings and sysfs entries for the
	 * section of the memory we are removing.
	 *
	 * NOTE: Ideally, this should be done in generic code like
	 * remove_memory(). But remove_memory() gets called by writing
	 * to sysfs "state" file and we can't remove sysfs entries
	 * while writing to it. So we have to defer it to here.
	 */
	sections_to_remove = (memblock_size >> PAGE_SHIFT) / PAGES_PER_SECTION;
	for (section = 0; section < sections_to_remove; section++) {
		unsigned long pfn = start_pfn + section * PAGES_PER_SECTION;
		ret = __remove_pages(zone, pfn, PAGES_PER_SECTION);
		if (ret)
			return ret;
	}

	/*
	 * Update memory regions for memory remove
	 */
	memblock_remove(base, memblock_size);

	/*
	 * Remove htab bolted mappings for this section of memory
	 */
	start = (unsigned long)__va(base);
	ret = remove_section_mapping(start, start + memblock_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_memory(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];

	ret = pseries_remove_memblock(base, lmb_size);
	return ret;
}
#else
static inline int pseries_remove_memblock(unsigned long base,
					  unsigned int memblock_size)
{
	return 0;
}
static inline int pseries_remove_memory(struct device_node *np)
{
	return -EOPNOTSUPP;
}
#endif /* CONFIG_MEMORY_HOTREMOVE */

static int pseries_add_memory(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 = get_memblock_size();
	if (!memblock_size)
		return -EINVAL;

	p = (u32 *)of_get_property(pr->dn, "ibm,dynamic-memory", NULL);
	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_memory(node);
		break;
	case OF_RECONFIG_DETACH_NODE:
		err = pseries_remove_memory(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);

	return 0;
}
machine_device_initcall(pseries, pseries_memory_hotplug_init);
Commit	Line	Data
57b53926 BP	1	/*
	2	* pseries Memory Hotplug infrastructure.
	3	*
	4	* Copyright (C) 2008 Badari Pulavarty, IBM Corporation
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License
	8	* as published by the Free Software Foundation; either version
	9	* 2 of the License, or (at your option) any later version.
	10	*/
	11
	12	#include <linux/of.h>
95f72d1e	13	#include <linux/memblock.h>
b4a26be9	14	#include <linux/vmalloc.h>
770e1ac5 BH	15	#include <linux/memory.h>
770e1ac5 BH	16
57b53926 BP	17	#include <asm/firmware.h>
57b53926 BP	18	#include <asm/machdep.h>
0b2f8287	19	#include <asm/sparsemem.h>
57b53926	20
c540ada2 NF	21	static unsigned long get_memblock_size(void)
	22	{
	23	struct device_node *np;
770e1ac5 BH	24	unsigned int memblock_size = MIN_MEMORY_BLOCK_SIZE;
770e1ac5 BH	25	struct resource r;
c540ada2 NF	26
	27	np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
	28	if (np) {
770e1ac5	29	const __be64 *size;
c540ada2 NF	30
c540ada2 NF	31	size = of_get_property(np, "ibm,lmb-size", NULL);
770e1ac5 BH	32	if (size)
770e1ac5 BH	33	memblock_size = be64_to_cpup(size);
c540ada2	34	of_node_put(np);
770e1ac5 BH	35	} else if (machine_is(pseries)) {
770e1ac5 BH	36	/* This fallback really only applies to pseries */
c540ada2	37	unsigned int memzero_size = 0;
c540ada2 NF	38
	39	np = of_find_node_by_path("/memory@0");
	40	if (np) {
770e1ac5 BH	41	if (!of_address_to_resource(np, 0, &r))
770e1ac5 BH	42	memzero_size = resource_size(&r);
c540ada2 NF	43	of_node_put(np);
	44	}
	45
	46	if (memzero_size) {
	47	/* We now know the size of memory@0, use this to find
	48	* the first memoryblock and get its size.
	49	*/
	50	char buf[64];
	51
	52	sprintf(buf, "/memory@%x", memzero_size);
	53	np = of_find_node_by_path(buf);
	54	if (np) {
770e1ac5 BH	55	if (!of_address_to_resource(np, 0, &r))
770e1ac5 BH	56	memblock_size = resource_size(&r);
c540ada2 NF	57	of_node_put(np);
	58	}
	59	}
	60	}
c540ada2 NF	61	return memblock_size;
	62	}
	63
770e1ac5 BH	64	/* WARNING: This is going to override the generic definition whenever
	65	* pseries is built-in regardless of what platform is active at boot
	66	* time. This is fine for now as this is the only "option" and it
	67	* should work everywhere. If not, we'll have to turn this into a
	68	* ppc_md. callback
	69	*/
c540ada2 NF	70	unsigned long memory_block_size_bytes(void)
	71	{
	72	return get_memblock_size();
	73	}
	74
4edd7cef	75	#ifdef CONFIG_MEMORY_HOTREMOVE
95f72d1e	76	static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size)
57b53926	77	{
3c3f67ea	78	unsigned long start, start_pfn;
57b53926	79	struct zone *zone;
1633dbba YI	80	int ret;
	81	unsigned long section;
	82	unsigned long sections_to_remove;
92ecd179	83
9fd3f88c	84	start_pfn = base >> PAGE_SHIFT;
04badfd2 NF	85
04badfd2 NF	86	if (!pfn_valid(start_pfn)) {
95f72d1e	87	memblock_remove(base, memblock_size);
04badfd2 NF	88	return 0;
	89	}
	90
57b53926 BP	91	zone = page_zone(pfn_to_page(start_pfn));
	92
	93	/*
	94	* Remove section mappings and sysfs entries for the
	95	* section of the memory we are removing.
	96	*
	97	* NOTE: Ideally, this should be done in generic code like
	98	* remove_memory(). But remove_memory() gets called by writing
	99	* to sysfs "state" file and we can't remove sysfs entries
	100	* while writing to it. So we have to defer it to here.
	101	*/
d760afd4	102	sections_to_remove = (memblock_size >> PAGE_SHIFT) / PAGES_PER_SECTION;
1633dbba YI	103	for (section = 0; section < sections_to_remove; section++) {
1633dbba YI	104	unsigned long pfn = start_pfn + section * PAGES_PER_SECTION;
158544b1	105	ret = __remove_pages(zone, pfn, PAGES_PER_SECTION);
d760afd4 YI	106	if (ret)
	107	return ret;
	108	}
57b53926	109
98d5c21c BP	110	/*
	111	* Update memory regions for memory remove
	112	*/
95f72d1e	113	memblock_remove(base, memblock_size);
98d5c21c	114
57b53926 BP	115	/*
	116	* Remove htab bolted mappings for this section of memory
	117	*/
92ecd179	118	start = (unsigned long)__va(base);
95f72d1e	119	ret = remove_section_mapping(start, start + memblock_size);
b4a26be9 BH	120
	121	/* Ensure all vmalloc mappings are flushed in case they also
	122	* hit that section of memory
	123	*/
	124	vm_unmap_aliases();
	125
57b53926 BP	126	return ret;
	127	}
	128
3c3f67ea NF	129	static int pseries_remove_memory(struct device_node *np)
	130	{
	131	const char *type;
	132	const unsigned int *regs;
	133	unsigned long base;
3fdfd990	134	unsigned int lmb_size;
3c3f67ea NF	135	int ret = -EINVAL;
	136
	137	/*
	138	* Check to see if we are actually removing memory
	139	*/
	140	type = of_get_property(np, "device_type", NULL);
	141	if (type == NULL \|\| strcmp(type, "memory") != 0)
	142	return 0;
	143
	144	/*
95f72d1e	145	* Find the bae address and size of the memblock
3c3f67ea NF	146	*/
	147	regs = of_get_property(np, "reg", NULL);
	148	if (!regs)
	149	return ret;
	150
	151	base = (unsigned long )regs;
3fdfd990	152	lmb_size = regs[3];
3c3f67ea	153
3fdfd990	154	ret = pseries_remove_memblock(base, lmb_size);
3c3f67ea NF	155	return ret;
3c3f67ea NF	156	}
4edd7cef DR	157	#else
	158	static inline int pseries_remove_memblock(unsigned long base,
	159	unsigned int memblock_size)
	160	{
d08ed7a3	161	return 0;
4edd7cef DR	162	}
	163	static inline int pseries_remove_memory(struct device_node *np)
	164	{
	165	return -EOPNOTSUPP;
	166	}
	167	#endif /* CONFIG_MEMORY_HOTREMOVE */
3c3f67ea	168
98d5c21c BP	169	static int pseries_add_memory(struct device_node *np)
	170	{
	171	const char *type;
98d5c21c	172	const unsigned int *regs;
92ecd179	173	unsigned long base;
3fdfd990	174	unsigned int lmb_size;
98d5c21c BP	175	int ret = -EINVAL;
	176
	177	/*
	178	* Check to see if we are actually adding memory
	179	*/
	180	type = of_get_property(np, "device_type", NULL);
	181	if (type == NULL \|\| strcmp(type, "memory") != 0)
	182	return 0;
	183
	184	/*
95f72d1e	185	* Find the base and size of the memblock
98d5c21c	186	*/
98d5c21c BP	187	regs = of_get_property(np, "reg", NULL);
	188	if (!regs)
	189	return ret;
	190
92ecd179	191	base = (unsigned long )regs;
3fdfd990	192	lmb_size = regs[3];
98d5c21c BP	193
	194	/*
	195	* Update memory region to represent the memory add
	196	*/
3fdfd990	197	ret = memblock_add(base, lmb_size);
3c3f67ea NF	198	return (ret < 0) ? -EINVAL : 0;
	199	}
	200
1cf3d8b3	201	static int pseries_update_drconf_memory(struct of_prop_reconfig *pr)
3c3f67ea	202	{
1cf3d8b3	203	struct of_drconf_cell new_drmem, old_drmem;
c540ada2	204	unsigned long memblock_size;
1cf3d8b3 NF	205	u32 entries;
	206	u32 *p;
	207	int i, rc = -EINVAL;
3c3f67ea	208
c540ada2 NF	209	memblock_size = get_memblock_size();
c540ada2 NF	210	if (!memblock_size)
3c3f67ea NF	211	return -EINVAL;
3c3f67ea NF	212
1cf3d8b3 NF	213	p = (u32 *)of_get_property(pr->dn, "ibm,dynamic-memory", NULL);
	214	if (!p)
	215	return -EINVAL;
	216
	217	/* The first int of the property is the number of lmb's described
	218	* by the property. This is followed by an array of of_drconf_cell
	219	* entries. Get the niumber of entries and skip to the array of
	220	* of_drconf_cell's.
	221	*/
	222	entries = *p++;
	223	old_drmem = (struct of_drconf_cell *)p;
	224
	225	p = (u32 *)pr->prop->value;
	226	p++;
	227	new_drmem = (struct of_drconf_cell *)p;
	228
	229	for (i = 0; i < entries; i++) {
	230	if ((old_drmem[i].flags & DRCONF_MEM_ASSIGNED) &&
	231	(!(new_drmem[i].flags & DRCONF_MEM_ASSIGNED))) {
	232	rc = pseries_remove_memblock(old_drmem[i].base_addr,
	233	memblock_size);
	234	break;
	235	} else if ((!(old_drmem[i].flags & DRCONF_MEM_ASSIGNED)) &&
	236	(new_drmem[i].flags & DRCONF_MEM_ASSIGNED)) {
	237	rc = memblock_add(old_drmem[i].base_addr,
	238	memblock_size);
	239	rc = (rc < 0) ? -EINVAL : 0;
	240	break;
	241	}
3c3f67ea NF	242	}
3c3f67ea NF	243
3c3f67ea	244	return rc;
98d5c21c BP	245	}
98d5c21c BP	246
57b53926	247	static int pseries_memory_notifier(struct notifier_block *nb,
1cf3d8b3	248	unsigned long action, void *node)
57b53926	249	{
1cf3d8b3	250	struct of_prop_reconfig *pr;
de2780a3	251	int err = 0;
57b53926 BP	252
57b53926 BP	253	switch (action) {
1cf3d8b3	254	case OF_RECONFIG_ATTACH_NODE:
de2780a3	255	err = pseries_add_memory(node);
57b53926	256	break;
1cf3d8b3	257	case OF_RECONFIG_DETACH_NODE:
de2780a3	258	err = pseries_remove_memory(node);
57b53926	259	break;
1cf3d8b3 NF	260	case OF_RECONFIG_UPDATE_PROPERTY:
	261	pr = (struct of_prop_reconfig *)node;
	262	if (!strcmp(pr->prop->name, "ibm,dynamic-memory"))
	263	err = pseries_update_drconf_memory(pr);
57b53926 BP	264	break;
57b53926 BP	265	}
de2780a3	266	return notifier_from_errno(err);
57b53926 BP	267	}
	268
	269	static struct notifier_block pseries_mem_nb = {
	270	.notifier_call = pseries_memory_notifier,
	271	};
	272
	273	static int __init pseries_memory_hotplug_init(void)
	274	{
	275	if (firmware_has_feature(FW_FEATURE_LPAR))
1cf3d8b3	276	of_reconfig_notifier_register(&pseries_mem_nb);
57b53926 BP	277
	278	return 0;
	279	}
	280	machine_device_initcall(pseries, pseries_memory_hotplug_init);