| /* |
| * 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/pSeries_reconfig.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(); |
| } |
| |
| static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size) |
| { |
| unsigned long start, start_pfn; |
| struct zone *zone; |
| int ret; |
| |
| 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. |
| */ |
| ret = __remove_pages(zone, start_pfn, memblock_size >> PAGE_SHIFT); |
| 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; |
| } |
| |
| 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_drconf_memory(unsigned long *base, unsigned int action) |
| { |
| unsigned long memblock_size; |
| int rc; |
| |
| memblock_size = get_memblock_size(); |
| if (!memblock_size) |
| return -EINVAL; |
| |
| if (action == PSERIES_DRCONF_MEM_ADD) { |
| rc = memblock_add(*base, memblock_size); |
| rc = (rc < 0) ? -EINVAL : 0; |
| } else if (action == PSERIES_DRCONF_MEM_REMOVE) { |
| rc = pseries_remove_memblock(*base, memblock_size); |
| } else { |
| rc = -EINVAL; |
| } |
| |
| return rc; |
| } |
| |
| static int pseries_memory_notifier(struct notifier_block *nb, |
| unsigned long action, void *node) |
| { |
| int err = 0; |
| |
| switch (action) { |
| case PSERIES_RECONFIG_ADD: |
| err = pseries_add_memory(node); |
| break; |
| case PSERIES_RECONFIG_REMOVE: |
| err = pseries_remove_memory(node); |
| break; |
| case PSERIES_DRCONF_MEM_ADD: |
| case PSERIES_DRCONF_MEM_REMOVE: |
| err = pseries_drconf_memory(node, action); |
| 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)) |
| pSeries_reconfig_notifier_register(&pseries_mem_nb); |
| |
| return 0; |
| } |
| machine_device_initcall(pseries, pseries_memory_hotplug_init); |