Nathan Fontenot | 6c6ea53 | 2017-12-01 10:47:08 -0600 | [diff] [blame] | 1 | /* |
| 2 | * Dynamic reconfiguration memory support |
| 3 | * |
| 4 | * Copyright 2017 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 | #define pr_fmt(fmt) "drmem: " fmt |
| 13 | |
| 14 | #include <linux/kernel.h> |
| 15 | #include <linux/of.h> |
| 16 | #include <linux/of_fdt.h> |
| 17 | #include <linux/memblock.h> |
| 18 | #include <asm/prom.h> |
| 19 | #include <asm/drmem.h> |
| 20 | |
| 21 | static struct drmem_lmb_info __drmem_info; |
| 22 | struct drmem_lmb_info *drmem_info = &__drmem_info; |
| 23 | |
Nathan Fontenot | 514a9cb | 2017-12-01 10:47:21 -0600 | [diff] [blame] | 24 | u64 drmem_lmb_memory_max(void) |
| 25 | { |
| 26 | struct drmem_lmb *last_lmb; |
| 27 | |
| 28 | last_lmb = &drmem_info->lmbs[drmem_info->n_lmbs - 1]; |
| 29 | return last_lmb->base_addr + drmem_lmb_size(); |
| 30 | } |
| 31 | |
Nathan Fontenot | 6195a50 | 2017-12-01 10:47:31 -0600 | [diff] [blame] | 32 | static u32 drmem_lmb_flags(struct drmem_lmb *lmb) |
| 33 | { |
| 34 | /* |
| 35 | * Return the value of the lmb flags field minus the reserved |
| 36 | * bit used internally for hotplug processing. |
| 37 | */ |
| 38 | return lmb->flags & ~DRMEM_LMB_RESERVED; |
| 39 | } |
| 40 | |
| 41 | static struct property *clone_property(struct property *prop, u32 prop_sz) |
| 42 | { |
| 43 | struct property *new_prop; |
| 44 | |
| 45 | new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL); |
| 46 | if (!new_prop) |
| 47 | return NULL; |
| 48 | |
| 49 | new_prop->name = kstrdup(prop->name, GFP_KERNEL); |
| 50 | new_prop->value = kzalloc(prop_sz, GFP_KERNEL); |
| 51 | if (!new_prop->name || !new_prop->value) { |
| 52 | kfree(new_prop->name); |
| 53 | kfree(new_prop->value); |
| 54 | kfree(new_prop); |
| 55 | return NULL; |
| 56 | } |
| 57 | |
| 58 | new_prop->length = prop_sz; |
| 59 | #if defined(CONFIG_OF_DYNAMIC) |
| 60 | of_property_set_flag(new_prop, OF_DYNAMIC); |
| 61 | #endif |
| 62 | return new_prop; |
| 63 | } |
| 64 | |
| 65 | static int drmem_update_dt_v1(struct device_node *memory, |
| 66 | struct property *prop) |
| 67 | { |
| 68 | struct property *new_prop; |
Nathan Fontenot | 2c77721 | 2017-12-01 10:47:42 -0600 | [diff] [blame^] | 69 | struct of_drconf_cell_v1 *dr_cell; |
Nathan Fontenot | 6195a50 | 2017-12-01 10:47:31 -0600 | [diff] [blame] | 70 | struct drmem_lmb *lmb; |
| 71 | u32 *p; |
| 72 | |
| 73 | new_prop = clone_property(prop, prop->length); |
| 74 | if (!new_prop) |
| 75 | return -1; |
| 76 | |
| 77 | p = new_prop->value; |
| 78 | *p++ = cpu_to_be32(drmem_info->n_lmbs); |
| 79 | |
Nathan Fontenot | 2c77721 | 2017-12-01 10:47:42 -0600 | [diff] [blame^] | 80 | dr_cell = (struct of_drconf_cell_v1 *)p; |
Nathan Fontenot | 6195a50 | 2017-12-01 10:47:31 -0600 | [diff] [blame] | 81 | |
| 82 | for_each_drmem_lmb(lmb) { |
| 83 | dr_cell->base_addr = cpu_to_be64(lmb->base_addr); |
| 84 | dr_cell->drc_index = cpu_to_be32(lmb->drc_index); |
| 85 | dr_cell->aa_index = cpu_to_be32(lmb->aa_index); |
| 86 | dr_cell->flags = cpu_to_be32(drmem_lmb_flags(lmb)); |
| 87 | |
| 88 | dr_cell++; |
| 89 | } |
| 90 | |
| 91 | of_update_property(memory, new_prop); |
| 92 | return 0; |
| 93 | } |
| 94 | |
| 95 | int drmem_update_dt(void) |
| 96 | { |
| 97 | struct device_node *memory; |
| 98 | struct property *prop; |
| 99 | int rc = -1; |
| 100 | |
| 101 | memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory"); |
| 102 | if (!memory) |
| 103 | return -1; |
| 104 | |
| 105 | prop = of_find_property(memory, "ibm,dynamic-memory", NULL); |
| 106 | if (prop) |
| 107 | rc = drmem_update_dt_v1(memory, prop); |
| 108 | |
| 109 | of_node_put(memory); |
| 110 | return rc; |
| 111 | } |
| 112 | |
Nathan Fontenot | 6c6ea53 | 2017-12-01 10:47:08 -0600 | [diff] [blame] | 113 | static void __init read_drconf_v1_cell(struct drmem_lmb *lmb, |
| 114 | const __be32 **prop) |
| 115 | { |
| 116 | const __be32 *p = *prop; |
| 117 | |
| 118 | lmb->base_addr = dt_mem_next_cell(dt_root_addr_cells, &p); |
| 119 | lmb->drc_index = of_read_number(p++, 1); |
| 120 | |
| 121 | p++; /* skip reserved field */ |
| 122 | |
| 123 | lmb->aa_index = of_read_number(p++, 1); |
| 124 | lmb->flags = of_read_number(p++, 1); |
| 125 | |
| 126 | *prop = p; |
| 127 | } |
| 128 | |
| 129 | static void __init __walk_drmem_v1_lmbs(const __be32 *prop, const __be32 *usm, |
| 130 | void (*func)(struct drmem_lmb *, const __be32 **)) |
| 131 | { |
| 132 | struct drmem_lmb lmb; |
| 133 | u32 i, n_lmbs; |
| 134 | |
| 135 | n_lmbs = of_read_number(prop++, 1); |
| 136 | |
| 137 | for (i = 0; i < n_lmbs; i++) { |
| 138 | read_drconf_v1_cell(&lmb, &prop); |
| 139 | func(&lmb, &usm); |
| 140 | } |
| 141 | } |
| 142 | |
Nathan Fontenot | 514a9cb | 2017-12-01 10:47:21 -0600 | [diff] [blame] | 143 | #ifdef CONFIG_PPC_PSERIES |
Nathan Fontenot | 6c6ea53 | 2017-12-01 10:47:08 -0600 | [diff] [blame] | 144 | void __init walk_drmem_lmbs_early(unsigned long node, |
| 145 | void (*func)(struct drmem_lmb *, const __be32 **)) |
| 146 | { |
| 147 | const __be32 *prop, *usm; |
| 148 | int len; |
| 149 | |
| 150 | prop = of_get_flat_dt_prop(node, "ibm,lmb-size", &len); |
| 151 | if (!prop || len < dt_root_size_cells * sizeof(__be32)) |
| 152 | return; |
| 153 | |
| 154 | drmem_info->lmb_size = dt_mem_next_cell(dt_root_size_cells, &prop); |
| 155 | |
| 156 | usm = of_get_flat_dt_prop(node, "linux,drconf-usable-memory", &len); |
| 157 | |
| 158 | prop = of_get_flat_dt_prop(node, "ibm,dynamic-memory", &len); |
| 159 | if (prop) |
| 160 | __walk_drmem_v1_lmbs(prop, usm, func); |
| 161 | |
| 162 | memblock_dump_all(); |
| 163 | } |
| 164 | |
| 165 | #endif |
Nathan Fontenot | 514a9cb | 2017-12-01 10:47:21 -0600 | [diff] [blame] | 166 | |
| 167 | static int __init init_drmem_lmb_size(struct device_node *dn) |
| 168 | { |
| 169 | const __be32 *prop; |
| 170 | int len; |
| 171 | |
| 172 | if (drmem_info->lmb_size) |
| 173 | return 0; |
| 174 | |
| 175 | prop = of_get_property(dn, "ibm,lmb-size", &len); |
| 176 | if (!prop || len < dt_root_size_cells * sizeof(__be32)) { |
| 177 | pr_info("Could not determine LMB size\n"); |
| 178 | return -1; |
| 179 | } |
| 180 | |
| 181 | drmem_info->lmb_size = dt_mem_next_cell(dt_root_size_cells, &prop); |
| 182 | return 0; |
| 183 | } |
| 184 | |
| 185 | /* |
| 186 | * Returns the property linux,drconf-usable-memory if |
| 187 | * it exists (the property exists only in kexec/kdump kernels, |
| 188 | * added by kexec-tools) |
| 189 | */ |
| 190 | static const __be32 *of_get_usable_memory(struct device_node *dn) |
| 191 | { |
| 192 | const __be32 *prop; |
| 193 | u32 len; |
| 194 | |
| 195 | prop = of_get_property(dn, "linux,drconf-usable-memory", &len); |
| 196 | if (!prop || len < sizeof(unsigned int)) |
| 197 | return NULL; |
| 198 | |
| 199 | return prop; |
| 200 | } |
| 201 | |
| 202 | void __init walk_drmem_lmbs(struct device_node *dn, |
| 203 | void (*func)(struct drmem_lmb *, const __be32 **)) |
| 204 | { |
| 205 | const __be32 *prop, *usm; |
| 206 | |
| 207 | if (init_drmem_lmb_size(dn)) |
| 208 | return; |
| 209 | |
| 210 | usm = of_get_usable_memory(dn); |
| 211 | |
| 212 | prop = of_get_property(dn, "ibm,dynamic-memory", NULL); |
| 213 | if (prop) |
| 214 | __walk_drmem_v1_lmbs(prop, usm, func); |
| 215 | } |
| 216 | |
| 217 | static void __init init_drmem_v1_lmbs(const __be32 *prop) |
| 218 | { |
| 219 | struct drmem_lmb *lmb; |
| 220 | |
| 221 | drmem_info->n_lmbs = of_read_number(prop++, 1); |
| 222 | |
| 223 | drmem_info->lmbs = kcalloc(drmem_info->n_lmbs, sizeof(*lmb), |
| 224 | GFP_KERNEL); |
| 225 | if (!drmem_info->lmbs) |
| 226 | return; |
| 227 | |
| 228 | for_each_drmem_lmb(lmb) |
| 229 | read_drconf_v1_cell(lmb, &prop); |
| 230 | } |
| 231 | |
| 232 | static int __init drmem_init(void) |
| 233 | { |
| 234 | struct device_node *dn; |
| 235 | const __be32 *prop; |
| 236 | |
| 237 | dn = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory"); |
| 238 | if (!dn) { |
| 239 | pr_info("No dynamic reconfiguration memory found\n"); |
| 240 | return 0; |
| 241 | } |
| 242 | |
| 243 | if (init_drmem_lmb_size(dn)) { |
| 244 | of_node_put(dn); |
| 245 | return 0; |
| 246 | } |
| 247 | |
| 248 | prop = of_get_property(dn, "ibm,dynamic-memory", NULL); |
| 249 | if (prop) |
| 250 | init_drmem_v1_lmbs(prop); |
| 251 | |
| 252 | of_node_put(dn); |
| 253 | return 0; |
| 254 | } |
| 255 | late_initcall(drmem_init); |