diff options
Diffstat (limited to 'target/linux/generic/pending-4.9/160-0001-mtd-partitions-add-of_match_table-parser-matching-fo.patch')
| -rw-r--r-- | target/linux/generic/pending-4.9/160-0001-mtd-partitions-add-of_match_table-parser-matching-fo.patch | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/target/linux/generic/pending-4.9/160-0001-mtd-partitions-add-of_match_table-parser-matching-fo.patch b/target/linux/generic/pending-4.9/160-0001-mtd-partitions-add-of_match_table-parser-matching-fo.patch new file mode 100644 index 0000000000..3a0115d521 --- /dev/null +++ b/target/linux/generic/pending-4.9/160-0001-mtd-partitions-add-of_match_table-parser-matching-fo.patch @@ -0,0 +1,194 @@ +From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl> +Date: Tue, 30 Jan 2018 11:55:16 +0100 +Subject: [PATCH V10 1/3] mtd: partitions: add of_match_table parser matching + for the "ofpart" type +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +In order to properly support compatibility strings as described in the +bindings/mtd/partition.txt "ofpart" type should be treated as an +indication for looking into OF. MTD should check "compatible" property +and search for a matching parser rather than blindly trying the one +supporting "fixed-partitions". + +It also means that existing "fixed-partitions" parser should get renamed +to use a more meaningful name. + +This commit achievies that aim by introducing a new mtd_part_of_parse(). +It works by looking for a matching parser for every string in the +"compatibility" property (starting with the most specific one). + +Please note that driver-specified parsers still take a precedence. It's +assumed that driver providing a parser type has a good reason for that +(e.g. having platform data with device-specific info). Also doing +otherwise could break existing setups. The same applies to using default +parsers (including "cmdlinepart") as some overwrite DT data with cmdline +argument. + +Partition parsers can now provide an of_match_table to enable +flash<-->parser matching via device tree as documented in the +mtd/partition.txt. + +This support is currently limited to built-in parsers as it uses +request_module() and friends. This should be sufficient for most cases +though as compiling parsers as modules isn't a common choice. + +Signed-off-by: Brian Norris <computersforpeace@gmail.com> +Signed-off-by: Rafał Miłecki <rafal@milecki.pl> +Tested-by: Peter Rosin <peda@axentia.se> +--- + +--- a/drivers/mtd/mtdpart.c ++++ b/drivers/mtd/mtdpart.c +@@ -30,6 +30,7 @@ + #include <linux/mtd/mtd.h> + #include <linux/mtd/partitions.h> + #include <linux/err.h> ++#include <linux/of.h> + + #include "mtdcore.h" + +@@ -886,6 +887,92 @@ static int mtd_part_do_parse(struct mtd_ + } + + /** ++ * mtd_part_get_compatible_parser - find MTD parser by a compatible string ++ * ++ * @compat: compatible string describing partitions in a device tree ++ * ++ * MTD parsers can specify supported partitions by providing a table of ++ * compatibility strings. This function finds a parser that advertises support ++ * for a passed value of "compatible". ++ */ ++static struct mtd_part_parser *mtd_part_get_compatible_parser(const char *compat) ++{ ++ struct mtd_part_parser *p, *ret = NULL; ++ ++ spin_lock(&part_parser_lock); ++ ++ list_for_each_entry(p, &part_parsers, list) { ++ const struct of_device_id *matches; ++ ++ matches = p->of_match_table; ++ if (!matches) ++ continue; ++ ++ for (; matches->compatible[0]; matches++) { ++ if (!strcmp(matches->compatible, compat) && ++ try_module_get(p->owner)) { ++ ret = p; ++ break; ++ } ++ } ++ ++ if (ret) ++ break; ++ } ++ ++ spin_unlock(&part_parser_lock); ++ ++ return ret; ++} ++ ++static int mtd_part_of_parse(struct mtd_info *master, ++ struct mtd_partitions *pparts) ++{ ++ struct mtd_part_parser *parser; ++ struct device_node *np; ++ struct property *prop; ++ const char *compat; ++ const char *fixed = "ofpart"; ++ int ret, err = 0; ++ ++ np = of_get_child_by_name(mtd_get_of_node(master), "partitions"); ++ of_property_for_each_string(np, "compatible", prop, compat) { ++ parser = mtd_part_get_compatible_parser(compat); ++ if (!parser) ++ continue; ++ ret = mtd_part_do_parse(parser, master, pparts, NULL); ++ if (ret > 0) { ++ of_node_put(np); ++ return ret; ++ } ++ mtd_part_parser_put(parser); ++ if (ret < 0 && !err) ++ err = ret; ++ } ++ of_node_put(np); ++ ++ /* ++ * For backward compatibility we have to try the "ofpart" ++ * parser. It supports old DT format with partitions specified as a ++ * direct subnodes of a flash device DT node without any compatibility ++ * specified we could match. ++ */ ++ parser = mtd_part_parser_get(fixed); ++ if (!parser && !request_module("%s", fixed)) ++ parser = mtd_part_parser_get(fixed); ++ if (parser) { ++ ret = mtd_part_do_parse(parser, master, pparts, NULL); ++ if (ret > 0) ++ return ret; ++ mtd_part_parser_put(parser); ++ if (ret < 0 && !err) ++ err = ret; ++ } ++ ++ return err; ++} ++ ++/** + * parse_mtd_partitions - parse MTD partitions + * @master: the master partition (describes whole MTD device) + * @types: names of partition parsers to try or %NULL +@@ -917,19 +1004,30 @@ int parse_mtd_partitions(struct mtd_info + types = default_mtd_part_types; + + for ( ; *types; types++) { +- pr_debug("%s: parsing partitions %s\n", master->name, *types); +- parser = mtd_part_parser_get(*types); +- if (!parser && !request_module("%s", *types)) ++ /* ++ * ofpart is a special type that means OF partitioning info ++ * should be used. It requires a bit different logic so it is ++ * handled in a separated function. ++ */ ++ if (!strcmp(*types, "ofpart")) { ++ ret = mtd_part_of_parse(master, pparts); ++ } else { ++ pr_debug("%s: parsing partitions %s\n", master->name, ++ *types); + parser = mtd_part_parser_get(*types); +- pr_debug("%s: got parser %s\n", master->name, +- parser ? parser->name : NULL); +- if (!parser) +- continue; +- ret = mtd_part_do_parse(parser, master, pparts, data); ++ if (!parser && !request_module("%s", *types)) ++ parser = mtd_part_parser_get(*types); ++ pr_debug("%s: got parser %s\n", master->name, ++ parser ? parser->name : NULL); ++ if (!parser) ++ continue; ++ ret = mtd_part_do_parse(parser, master, pparts, data); ++ if (ret <= 0) ++ mtd_part_parser_put(parser); ++ } + /* Found partitions! */ + if (ret > 0) + return 0; +- mtd_part_parser_put(parser); + /* + * Stash the first error we see; only report it if no parser + * succeeds +--- a/include/linux/mtd/partitions.h ++++ b/include/linux/mtd/partitions.h +@@ -77,6 +77,7 @@ struct mtd_part_parser { + struct list_head list; + struct module *owner; + const char *name; ++ const struct of_device_id *of_match_table; + int (*parse_fn)(struct mtd_info *, const struct mtd_partition **, + struct mtd_part_parser_data *); + void (*cleanup)(const struct mtd_partition *pparts, int nr_parts); |