Badari Pulavarty | 57b5392 | 2008-04-18 13:33:50 -0700 | [diff] [blame] | 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> |
Badari Pulavarty | 98d5c21 | 2008-04-18 13:33:52 -0700 | [diff] [blame^] | 13 | #include <linux/lmb.h> |
Badari Pulavarty | 57b5392 | 2008-04-18 13:33:50 -0700 | [diff] [blame] | 14 | #include <asm/firmware.h> |
| 15 | #include <asm/machdep.h> |
| 16 | #include <asm/pSeries_reconfig.h> |
| 17 | |
| 18 | static int pseries_remove_memory(struct device_node *np) |
| 19 | { |
| 20 | const char *type; |
| 21 | const unsigned int *my_index; |
| 22 | const unsigned int *regs; |
| 23 | u64 start_pfn, start; |
| 24 | struct zone *zone; |
| 25 | int ret = -EINVAL; |
| 26 | |
| 27 | /* |
| 28 | * Check to see if we are actually removing memory |
| 29 | */ |
| 30 | type = of_get_property(np, "device_type", NULL); |
| 31 | if (type == NULL || strcmp(type, "memory") != 0) |
| 32 | return 0; |
| 33 | |
| 34 | /* |
| 35 | * Find the memory index and size of the removing section |
| 36 | */ |
| 37 | my_index = of_get_property(np, "ibm,my-drc-index", NULL); |
| 38 | if (!my_index) |
| 39 | return ret; |
| 40 | |
| 41 | regs = of_get_property(np, "reg", NULL); |
| 42 | if (!regs) |
| 43 | return ret; |
| 44 | |
| 45 | start_pfn = section_nr_to_pfn(*my_index & 0xffff); |
| 46 | zone = page_zone(pfn_to_page(start_pfn)); |
| 47 | |
| 48 | /* |
| 49 | * Remove section mappings and sysfs entries for the |
| 50 | * section of the memory we are removing. |
| 51 | * |
| 52 | * NOTE: Ideally, this should be done in generic code like |
| 53 | * remove_memory(). But remove_memory() gets called by writing |
| 54 | * to sysfs "state" file and we can't remove sysfs entries |
| 55 | * while writing to it. So we have to defer it to here. |
| 56 | */ |
| 57 | ret = __remove_pages(zone, start_pfn, regs[3] >> PAGE_SHIFT); |
| 58 | if (ret) |
| 59 | return ret; |
| 60 | |
| 61 | /* |
Badari Pulavarty | 98d5c21 | 2008-04-18 13:33:52 -0700 | [diff] [blame^] | 62 | * Update memory regions for memory remove |
| 63 | */ |
| 64 | lmb_remove(start_pfn << PAGE_SHIFT, regs[3]); |
| 65 | |
| 66 | /* |
Badari Pulavarty | 57b5392 | 2008-04-18 13:33:50 -0700 | [diff] [blame] | 67 | * Remove htab bolted mappings for this section of memory |
| 68 | */ |
| 69 | start = (unsigned long)__va(start_pfn << PAGE_SHIFT); |
| 70 | ret = remove_section_mapping(start, start + regs[3]); |
| 71 | return ret; |
| 72 | } |
| 73 | |
Badari Pulavarty | 98d5c21 | 2008-04-18 13:33:52 -0700 | [diff] [blame^] | 74 | static int pseries_add_memory(struct device_node *np) |
| 75 | { |
| 76 | const char *type; |
| 77 | const unsigned int *my_index; |
| 78 | const unsigned int *regs; |
| 79 | u64 start_pfn; |
| 80 | int ret = -EINVAL; |
| 81 | |
| 82 | /* |
| 83 | * Check to see if we are actually adding memory |
| 84 | */ |
| 85 | type = of_get_property(np, "device_type", NULL); |
| 86 | if (type == NULL || strcmp(type, "memory") != 0) |
| 87 | return 0; |
| 88 | |
| 89 | /* |
| 90 | * Find the memory index and size of the added section |
| 91 | */ |
| 92 | my_index = of_get_property(np, "ibm,my-drc-index", NULL); |
| 93 | if (!my_index) |
| 94 | return ret; |
| 95 | |
| 96 | regs = of_get_property(np, "reg", NULL); |
| 97 | if (!regs) |
| 98 | return ret; |
| 99 | |
| 100 | start_pfn = section_nr_to_pfn(*my_index & 0xffff); |
| 101 | |
| 102 | /* |
| 103 | * Update memory region to represent the memory add |
| 104 | */ |
| 105 | lmb_add(start_pfn << PAGE_SHIFT, regs[3]); |
| 106 | return 0; |
| 107 | } |
| 108 | |
Badari Pulavarty | 57b5392 | 2008-04-18 13:33:50 -0700 | [diff] [blame] | 109 | static int pseries_memory_notifier(struct notifier_block *nb, |
| 110 | unsigned long action, void *node) |
| 111 | { |
| 112 | int err = NOTIFY_OK; |
| 113 | |
| 114 | switch (action) { |
| 115 | case PSERIES_RECONFIG_ADD: |
Badari Pulavarty | 98d5c21 | 2008-04-18 13:33:52 -0700 | [diff] [blame^] | 116 | if (pseries_add_memory(node)) |
| 117 | err = NOTIFY_BAD; |
Badari Pulavarty | 57b5392 | 2008-04-18 13:33:50 -0700 | [diff] [blame] | 118 | break; |
| 119 | case PSERIES_RECONFIG_REMOVE: |
| 120 | if (pseries_remove_memory(node)) |
| 121 | err = NOTIFY_BAD; |
| 122 | break; |
| 123 | default: |
| 124 | err = NOTIFY_DONE; |
| 125 | break; |
| 126 | } |
| 127 | return err; |
| 128 | } |
| 129 | |
| 130 | static struct notifier_block pseries_mem_nb = { |
| 131 | .notifier_call = pseries_memory_notifier, |
| 132 | }; |
| 133 | |
| 134 | static int __init pseries_memory_hotplug_init(void) |
| 135 | { |
| 136 | if (firmware_has_feature(FW_FEATURE_LPAR)) |
| 137 | pSeries_reconfig_notifier_register(&pseries_mem_nb); |
| 138 | |
| 139 | return 0; |
| 140 | } |
| 141 | machine_device_initcall(pseries, pseries_memory_hotplug_init); |