[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/lmb.h>
#include <asm/firmware.h>
#include <asm/machdep.h>
#include <asm/pSeries_reconfig.h>
#include <asm/sparsemem.h>

static int pseries_remove_lmb(unsigned long base, unsigned int lmb_size)
{
	unsigned long start, start_pfn;
	struct zone *zone;
	int ret;

	start_pfn = base >> PAGE_SHIFT;

	if (!pfn_valid(start_pfn)) {
		lmb_remove(base, lmb_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.
	 */
	ret = __remove_pages(zone, start_pfn, lmb_size >> PAGE_SHIFT);
	if (ret)
		return ret;

	/*
	 * Update memory regions for memory remove
	 */
	lmb_remove(base, lmb_size);

	/*
	 * Remove htab bolted mappings for this section of memory
	 */
	start = (unsigned long)__va(base);
	ret = remove_section_mapping(start, start + lmb_size);
	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 lmb
	 */
	regs = of_get_property(np, "reg", NULL);
	if (!regs)
		return ret;

	base = *(unsigned long *)regs;
	lmb_size = regs[3];

	ret = pseries_remove_lmb(base, lmb_size);
	return ret;
}

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 lmb
	 */
	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 = lmb_add(base, lmb_size);
	return (ret < 0) ? -EINVAL : 0;
}

static int pseries_drconf_memory(unsigned long *base, unsigned int action)
{
	struct device_node *np;
	const unsigned long *lmb_size;
	int rc;

	np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
	if (!np)
		return -EINVAL;

	lmb_size = of_get_property(np, "ibm,lmb-size", NULL);
	if (!lmb_size) {
		of_node_put(np);
		return -EINVAL;
	}

	if (action == PSERIES_DRCONF_MEM_ADD) {
		rc = lmb_add(*base, *lmb_size);
		rc = (rc < 0) ? -EINVAL : 0;
	} else if (action == PSERIES_DRCONF_MEM_REMOVE) {
		rc = pseries_remove_lmb(*base, *lmb_size);
	} else {
		rc = -EINVAL;
	}

	of_node_put(np);
	return rc;
}

static int pseries_memory_notifier(struct notifier_block *nb,
				unsigned long action, void *node)
{
	int err = NOTIFY_OK;

	switch (action) {
	case PSERIES_RECONFIG_ADD:
		if (pseries_add_memory(node))
			err = NOTIFY_BAD;
		break;
	case PSERIES_RECONFIG_REMOVE:
		if (pseries_remove_memory(node))
			err = NOTIFY_BAD;
		break;
	case PSERIES_DRCONF_MEM_ADD:
	case PSERIES_DRCONF_MEM_REMOVE:
		if (pseries_drconf_memory(node, action))
			err = NOTIFY_BAD;
		break;
	default:
		err = NOTIFY_DONE;
		break;
	}
	return 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))
		pSeries_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>
98d5c21c	13	#include <linux/lmb.h>
57b53926 BP	14	#include <asm/firmware.h>
	15	#include <asm/machdep.h>
	16	#include <asm/pSeries_reconfig.h>
0b2f8287	17	#include <asm/sparsemem.h>
57b53926	18
3c3f67ea	19	static int pseries_remove_lmb(unsigned long base, unsigned int lmb_size)
57b53926	20	{
3c3f67ea	21	unsigned long start, start_pfn;
57b53926	22	struct zone *zone;
3c3f67ea	23	int ret;
92ecd179	24
9fd3f88c	25	start_pfn = base >> PAGE_SHIFT;
04badfd2 NF	26
	27	if (!pfn_valid(start_pfn)) {
	28	lmb_remove(base, lmb_size);
	29	return 0;
	30	}
	31
57b53926 BP	32	zone = page_zone(pfn_to_page(start_pfn));
	33
	34	/*
	35	* Remove section mappings and sysfs entries for the
	36	* section of the memory we are removing.
	37	*
	38	* NOTE: Ideally, this should be done in generic code like
	39	* remove_memory(). But remove_memory() gets called by writing
	40	* to sysfs "state" file and we can't remove sysfs entries
	41	* while writing to it. So we have to defer it to here.
	42	*/
92ecd179	43	ret = __remove_pages(zone, start_pfn, lmb_size >> PAGE_SHIFT);
57b53926 BP	44	if (ret)
	45	return ret;
	46
98d5c21c BP	47	/*
	48	* Update memory regions for memory remove
	49	*/
92ecd179	50	lmb_remove(base, lmb_size);
98d5c21c	51
57b53926 BP	52	/*
	53	* Remove htab bolted mappings for this section of memory
	54	*/
92ecd179 NF	55	start = (unsigned long)__va(base);
92ecd179 NF	56	ret = remove_section_mapping(start, start + lmb_size);
57b53926 BP	57	return ret;
	58	}
	59
3c3f67ea NF	60	static int pseries_remove_memory(struct device_node *np)
	61	{
	62	const char *type;
	63	const unsigned int *regs;
	64	unsigned long base;
	65	unsigned int lmb_size;
	66	int ret = -EINVAL;
	67
	68	/*
	69	* Check to see if we are actually removing memory
	70	*/
	71	type = of_get_property(np, "device_type", NULL);
	72	if (type == NULL \|\| strcmp(type, "memory") != 0)
	73	return 0;
	74
	75	/*
	76	* Find the bae address and size of the lmb
	77	*/
	78	regs = of_get_property(np, "reg", NULL);
	79	if (!regs)
	80	return ret;
	81
	82	base = (unsigned long )regs;
	83	lmb_size = regs[3];
	84
	85	ret = pseries_remove_lmb(base, lmb_size);
	86	return ret;
	87	}
	88
98d5c21c BP	89	static int pseries_add_memory(struct device_node *np)
	90	{
	91	const char *type;
98d5c21c	92	const unsigned int *regs;
92ecd179 NF	93	unsigned long base;
92ecd179 NF	94	unsigned int lmb_size;
98d5c21c BP	95	int ret = -EINVAL;
	96
	97	/*
	98	* Check to see if we are actually adding memory
	99	*/
	100	type = of_get_property(np, "device_type", NULL);
	101	if (type == NULL \|\| strcmp(type, "memory") != 0)
	102	return 0;
	103
	104	/*
92ecd179	105	* Find the base and size of the lmb
98d5c21c	106	*/
98d5c21c BP	107	regs = of_get_property(np, "reg", NULL);
	108	if (!regs)
	109	return ret;
	110
92ecd179 NF	111	base = (unsigned long )regs;
92ecd179 NF	112	lmb_size = regs[3];
98d5c21c BP	113
	114	/*
	115	* Update memory region to represent the memory add
	116	*/
3c3f67ea NF	117	ret = lmb_add(base, lmb_size);
	118	return (ret < 0) ? -EINVAL : 0;
	119	}
	120
	121	static int pseries_drconf_memory(unsigned long *base, unsigned int action)
	122	{
	123	struct device_node *np;
	124	const unsigned long *lmb_size;
	125	int rc;
	126
	127	np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
	128	if (!np)
	129	return -EINVAL;
	130
	131	lmb_size = of_get_property(np, "ibm,lmb-size", NULL);
	132	if (!lmb_size) {
	133	of_node_put(np);
	134	return -EINVAL;
	135	}
	136
	137	if (action == PSERIES_DRCONF_MEM_ADD) {
	138	rc = lmb_add(base, lmb_size);
	139	rc = (rc < 0) ? -EINVAL : 0;
	140	} else if (action == PSERIES_DRCONF_MEM_REMOVE) {
	141	rc = pseries_remove_lmb(base, lmb_size);
	142	} else {
	143	rc = -EINVAL;
	144	}
	145
	146	of_node_put(np);
	147	return rc;
98d5c21c BP	148	}
98d5c21c BP	149
57b53926 BP	150	static int pseries_memory_notifier(struct notifier_block *nb,
	151	unsigned long action, void *node)
	152	{
	153	int err = NOTIFY_OK;
	154
	155	switch (action) {
	156	case PSERIES_RECONFIG_ADD:
98d5c21c BP	157	if (pseries_add_memory(node))
98d5c21c BP	158	err = NOTIFY_BAD;
57b53926 BP	159	break;
	160	case PSERIES_RECONFIG_REMOVE:
	161	if (pseries_remove_memory(node))
	162	err = NOTIFY_BAD;
	163	break;
3c3f67ea NF	164	case PSERIES_DRCONF_MEM_ADD:
	165	case PSERIES_DRCONF_MEM_REMOVE:
	166	if (pseries_drconf_memory(node, action))
	167	err = NOTIFY_BAD;
	168	break;
57b53926 BP	169	default:
	170	err = NOTIFY_DONE;
	171	break;
	172	}
	173	return err;
	174	}
	175
	176	static struct notifier_block pseries_mem_nb = {
	177	.notifier_call = pseries_memory_notifier,
	178	};
	179
	180	static int __init pseries_memory_hotplug_init(void)
	181	{
	182	if (firmware_has_feature(FW_FEATURE_LPAR))
	183	pSeries_reconfig_notifier_register(&pseries_mem_nb);
	184
	185	return 0;
	186	}
	187	machine_device_initcall(pseries, pseries_memory_hotplug_init);