|  | /* | 
|  | * 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 -EOPNOTSUPP; | 
|  | } | 
|  | #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 *)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_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); |