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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Flash partitions described by the OF (or flattened) device tree4 *5 * Copyright © 2006 MontaVista Software Inc.6 * Author: Vitaly Wool <vwool@ru.mvista.com>7 *8 * Revised to handle newer style flash binding by:9 * Copyright © 2007 David Gibson, IBM Corporation.10 */11 12#include <linux/module.h>13#include <linux/init.h>14#include <linux/of.h>15#include <linux/mtd/mtd.h>16#include <linux/slab.h>17#include <linux/mtd/partitions.h>18 19#include "ofpart_bcm4908.h"20#include "ofpart_linksys_ns.h"21 22struct fixed_partitions_quirks {23 int (*post_parse)(struct mtd_info *mtd, struct mtd_partition *parts, int nr_parts);24};25 26static struct fixed_partitions_quirks bcm4908_partitions_quirks = {27 .post_parse = bcm4908_partitions_post_parse,28};29 30static struct fixed_partitions_quirks linksys_ns_partitions_quirks = {31 .post_parse = linksys_ns_partitions_post_parse,32};33 34static const struct of_device_id parse_ofpart_match_table[];35 36static bool node_has_compatible(struct device_node *pp)37{38 return of_get_property(pp, "compatible", NULL);39}40 41static int parse_fixed_partitions(struct mtd_info *master,42 const struct mtd_partition **pparts,43 struct mtd_part_parser_data *data)44{45 const struct fixed_partitions_quirks *quirks;46 const struct of_device_id *of_id;47 struct mtd_partition *parts;48 struct device_node *mtd_node;49 struct device_node *ofpart_node;50 const char *partname;51 struct device_node *pp;52 int nr_parts, i, ret = 0;53 bool dedicated = true;54 55 /* Pull of_node from the master device node */56 mtd_node = mtd_get_of_node(master);57 if (!mtd_node)58 return 0;59 60 if (!master->parent) { /* Master */61 ofpart_node = of_get_child_by_name(mtd_node, "partitions");62 if (!ofpart_node) {63 /*64 * We might get here even when ofpart isn't used at all (e.g.,65 * when using another parser), so don't be louder than66 * KERN_DEBUG67 */68 pr_debug("%s: 'partitions' subnode not found on %pOF. Trying to parse direct subnodes as partitions.\n",69 master->name, mtd_node);70 ofpart_node = mtd_node;71 dedicated = false;72 }73 } else { /* Partition */74 ofpart_node = mtd_node;75 }76 77 of_id = of_match_node(parse_ofpart_match_table, ofpart_node);78 if (dedicated && !of_id) {79 /* The 'partitions' subnode might be used by another parser */80 return 0;81 }82 83 quirks = of_id ? of_id->data : NULL;84 85 /* First count the subnodes */86 nr_parts = 0;87 for_each_child_of_node(ofpart_node, pp) {88 if (!dedicated && node_has_compatible(pp))89 continue;90 91 nr_parts++;92 }93 94 if (nr_parts == 0)95 return 0;96 97 parts = kcalloc(nr_parts, sizeof(*parts), GFP_KERNEL);98 if (!parts)99 return -ENOMEM;100 101 i = 0;102 for_each_child_of_node(ofpart_node, pp) {103 const __be32 *reg;104 int len;105 int a_cells, s_cells;106 107 if (!dedicated && node_has_compatible(pp))108 continue;109 110 reg = of_get_property(pp, "reg", &len);111 if (!reg) {112 if (dedicated) {113 pr_debug("%s: ofpart partition %pOF (%pOF) missing reg property.\n",114 master->name, pp,115 mtd_node);116 goto ofpart_fail;117 } else {118 nr_parts--;119 continue;120 }121 }122 123 a_cells = of_n_addr_cells(pp);124 s_cells = of_n_size_cells(pp);125 if (!dedicated && s_cells == 0) {126 /*127 * This is a ugly workaround to not create128 * regression on devices that are still creating129 * partitions as direct children of the nand controller.130 * This can happen in case the nand controller node has131 * #size-cells equal to 0 and the firmware (e.g.132 * U-Boot) just add the partitions there assuming133 * 32-bit addressing.134 *135 * If you get this warning your firmware and/or DTS136 * should be really fixed.137 *138 * This is working only for devices smaller than 4GiB.139 */140 pr_warn("%s: ofpart partition %pOF (%pOF) #size-cells is wrongly set to <0>, assuming <1> for parsing partitions.\n",141 master->name, pp, mtd_node);142 s_cells = 1;143 }144 if (len / 4 != a_cells + s_cells) {145 pr_debug("%s: ofpart partition %pOF (%pOF) error parsing reg property.\n",146 master->name, pp,147 mtd_node);148 goto ofpart_fail;149 }150 151 parts[i].offset = of_read_number(reg, a_cells);152 parts[i].size = of_read_number(reg + a_cells, s_cells);153 parts[i].of_node = pp;154 155 partname = of_get_property(pp, "label", &len);156 if (!partname)157 partname = of_get_property(pp, "name", &len);158 parts[i].name = partname;159 160 if (of_property_read_bool(pp, "read-only"))161 parts[i].mask_flags |= MTD_WRITEABLE;162 163 if (of_property_read_bool(pp, "lock"))164 parts[i].mask_flags |= MTD_POWERUP_LOCK;165 166 if (of_property_read_bool(pp, "slc-mode"))167 parts[i].add_flags |= MTD_SLC_ON_MLC_EMULATION;168 169 i++;170 }171 172 if (!nr_parts)173 goto ofpart_none;174 175 if (quirks && quirks->post_parse)176 quirks->post_parse(master, parts, nr_parts);177 178 *pparts = parts;179 return nr_parts;180 181ofpart_fail:182 pr_err("%s: error parsing ofpart partition %pOF (%pOF)\n",183 master->name, pp, mtd_node);184 ret = -EINVAL;185ofpart_none:186 of_node_put(pp);187 kfree(parts);188 return ret;189}190 191static const struct of_device_id parse_ofpart_match_table[] = {192 /* Generic */193 { .compatible = "fixed-partitions" },194 /* Customized */195 { .compatible = "brcm,bcm4908-partitions", .data = &bcm4908_partitions_quirks, },196 { .compatible = "linksys,ns-partitions", .data = &linksys_ns_partitions_quirks, },197 {},198};199MODULE_DEVICE_TABLE(of, parse_ofpart_match_table);200 201static struct mtd_part_parser ofpart_parser = {202 .parse_fn = parse_fixed_partitions,203 .name = "fixed-partitions",204 .of_match_table = parse_ofpart_match_table,205};206 207static int parse_ofoldpart_partitions(struct mtd_info *master,208 const struct mtd_partition **pparts,209 struct mtd_part_parser_data *data)210{211 struct mtd_partition *parts;212 struct device_node *dp;213 int i, plen, nr_parts;214 const struct {215 __be32 offset, len;216 } *part;217 const char *names;218 219 /* Pull of_node from the master device node */220 dp = mtd_get_of_node(master);221 if (!dp)222 return 0;223 224 part = of_get_property(dp, "partitions", &plen);225 if (!part)226 return 0; /* No partitions found */227 228 pr_warn("Device tree uses obsolete partition map binding: %pOF\n", dp);229 230 nr_parts = plen / sizeof(part[0]);231 232 parts = kcalloc(nr_parts, sizeof(*parts), GFP_KERNEL);233 if (!parts)234 return -ENOMEM;235 236 names = of_get_property(dp, "partition-names", &plen);237 238 for (i = 0; i < nr_parts; i++) {239 parts[i].offset = be32_to_cpu(part->offset);240 parts[i].size = be32_to_cpu(part->len) & ~1;241 /* bit 0 set signifies read only partition */242 if (be32_to_cpu(part->len) & 1)243 parts[i].mask_flags = MTD_WRITEABLE;244 245 if (names && (plen > 0)) {246 int len = strlen(names) + 1;247 248 parts[i].name = names;249 plen -= len;250 names += len;251 } else {252 parts[i].name = "unnamed";253 }254 255 part++;256 }257 258 *pparts = parts;259 return nr_parts;260}261 262static struct mtd_part_parser ofoldpart_parser = {263 .parse_fn = parse_ofoldpart_partitions,264 .name = "ofoldpart",265};266 267static int __init ofpart_parser_init(void)268{269 register_mtd_parser(&ofpart_parser);270 register_mtd_parser(&ofoldpart_parser);271 return 0;272}273 274static void __exit ofpart_parser_exit(void)275{276 deregister_mtd_parser(&ofpart_parser);277 deregister_mtd_parser(&ofoldpart_parser);278}279 280module_init(ofpart_parser_init);281module_exit(ofpart_parser_exit);282 283MODULE_LICENSE("GPL");284MODULE_DESCRIPTION("Parser for MTD partitioning information in device tree");285MODULE_AUTHOR("Vitaly Wool, David Gibson");286/*287 * When MTD core cannot find the requested parser, it tries to load the module288 * with the same name. Since we provide the ofoldpart parser, we should have289 * the corresponding alias.290 */291MODULE_ALIAS("fixed-partitions");292MODULE_ALIAS("ofoldpart");293