/* * 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 #include #include #include #include #include #include #include #include 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_reconfig_data *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 *) 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 *data) { struct of_reconfig_data *rd = data; 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: if (!strcmp(rd->prop->name, "ibm,dynamic-memory")) err = pseries_update_drconf_memory(rd); 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);