// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Flash partitions described by the OF (or flattened) device tree
*
* Copyright © 2006 MontaVista Software Inc.
* Author: Vitaly Wool <[email protected]>
*
* Revised to handle newer style flash binding by:
* Copyright © 2007 David Gibson, IBM Corporation.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/of.h>
#include <linux/mtd/mtd.h>
#include <linux/slab.h>
#include <linux/mtd/partitions.h>
#include "ofpart_bcm4908.h"
#include "ofpart_linksys_ns.h"
struct fixed_partitions_quirks {
int (*post_parse)(struct mtd_info *mtd, struct mtd_partition *parts, int nr_parts);
};
static struct fixed_partitions_quirks bcm4908_partitions_quirks = {
.post_parse = bcm4908_partitions_post_parse,
};
static struct fixed_partitions_quirks linksys_ns_partitions_quirks = {
.post_parse = linksys_ns_partitions_post_parse,
};
static const struct of_device_id parse_ofpart_match_table[];
static bool node_has_compatible(struct device_node *pp)
{
return of_get_property(pp, "compatible", NULL);
}
static int parse_fixed_partitions(struct mtd_info *master,
const struct mtd_partition **pparts,
struct mtd_part_parser_data *data)
{
const struct fixed_partitions_quirks *quirks;
const struct of_device_id *of_id;
struct mtd_partition *parts;
struct device_node *mtd_node;
struct device_node *ofpart_node;
const char *partname;
struct device_node *pp;
int nr_parts, i, ret = 0;
bool dedicated = true;
/* Pull of_node from the master device node */
mtd_node = mtd_get_of_node(master);
if (!mtd_node)
return 0;
if (!master->parent) { /* Master */
ofpart_node = of_get_child_by_name(mtd_node, "partitions");
if (!ofpart_node) {
/*
* We might get here even when ofpart isn't used at all (e.g.,
* when using another parser), so don't be louder than
* KERN_DEBUG
*/
pr_debug("%s: 'partitions' subnode not found on %pOF. Trying to parse direct subnodes as partitions.\n",
master->name, mtd_node);
ofpart_node = mtd_node;
dedicated = false;
}
} else { /* Partition */
ofpart_node = mtd_node;
}
of_id = of_match_node(parse_ofpart_match_table, ofpart_node);
if (dedicated && !of_id) {
/* The 'partitions' subnode might be used by another parser */
return 0;
}
quirks = of_id ? of_id->data : NULL;
/* First count the subnodes */
nr_parts = 0;
for_each_child_of_node(ofpart_node, pp) {
if (!dedicated && node_has_compatible(pp))
continue;
nr_parts++;
}
if (nr_parts == 0)
return 0;
parts = kcalloc(nr_parts, sizeof(*parts), GFP_KERNEL);
if (!parts)
return -ENOMEM;
i = 0;
for_each_child_of_node(ofpart_node, pp) {
const __be32 *reg;
int len;
int a_cells, s_cells;
if (!dedicated && node_has_compatible(pp))
continue;
reg = of_get_property(pp, "reg", &len);
if (!reg) {
if (dedicated) {
pr_debug("%s: ofpart partition %pOF (%pOF) missing reg property.\n",
master->name, pp,
mtd_node);
goto ofpart_fail;
} else {
nr_parts--;
continue;
}
}
a_cells = of_n_addr_cells(pp);
s_cells = of_n_size_cells(pp);
if (!dedicated && s_cells == 0) {
/*
* This is a ugly workaround to not create
* regression on devices that are still creating
* partitions as direct children of the nand controller.
* This can happen in case the nand controller node has
* #size-cells equal to 0 and the firmware (e.g.
* U-Boot) just add the partitions there assuming
* 32-bit addressing.
*
* If you get this warning your firmware and/or DTS
* should be really fixed.
*
* This is working only for devices smaller than 4GiB.
*/
pr_warn("%s: ofpart partition %pOF (%pOF) #size-cells is wrongly set to <0>, assuming <1> for parsing partitions.\n",
master->name, pp, mtd_node);
s_cells = 1;
}
if (len / 4 != a_cells + s_cells) {
pr_debug("%s: ofpart partition %pOF (%pOF) error parsing reg property.\n",
master->name, pp,
mtd_node);
goto ofpart_fail;
}
parts[i].offset = of_read_number(reg, a_cells);
parts[i].size = of_read_number(reg + a_cells, s_cells);
parts[i].of_node = pp;
partname = of_get_property(pp, "label", &len);
if (!partname)
partname = of_get_property(pp, "name", &len);
parts[i].name = partname;
if (of_property_read_bool(pp, "read-only"))
parts[i].mask_flags |= MTD_WRITEABLE;
if (of_property_read_bool(pp, "lock"))
parts[i].mask_flags |= MTD_POWERUP_LOCK;
if (of_property_read_bool(pp, "slc-mode"))
parts[i].add_flags |= MTD_SLC_ON_MLC_EMULATION;
i++;
}
if (!nr_parts)
goto ofpart_none;
if (quirks && quirks->post_parse)
quirks->post_parse(master, parts, nr_parts);
*pparts = parts;
return nr_parts;
ofpart_fail:
pr_err("%s: error parsing ofpart partition %pOF (%pOF)\n",
master->name, pp, mtd_node);
ret = -EINVAL;
ofpart_none:
of_node_put(pp);
kfree(parts);
return ret;
}
static const struct of_device_id parse_ofpart_match_table[] = {
/* Generic */
{ .compatible = "fixed-partitions" },
/* Customized */
{ .compatible = "brcm,bcm4908-partitions", .data = &bcm4908_partitions_quirks, },
{ .compatible = "linksys,ns-partitions", .data = &linksys_ns_partitions_quirks, },
{},
};
MODULE_DEVICE_TABLE(of, parse_ofpart_match_table);
static struct mtd_part_parser ofpart_parser = {
.parse_fn = parse_fixed_partitions,
.name = "fixed-partitions",
.of_match_table = parse_ofpart_match_table,
};
static int parse_ofoldpart_partitions(struct mtd_info *master,
const struct mtd_partition **pparts,
struct mtd_part_parser_data *data)
{
struct mtd_partition *parts;
struct device_node *dp;
int i, plen, nr_parts;
const struct {
__be32 offset, len;
} *part;
const char *names;
/* Pull of_node from the master device node */
dp = mtd_get_of_node(master);
if (!dp)
return 0;
part = of_get_property(dp, "partitions", &plen);
if (!part)
return 0; /* No partitions found */
pr_warn("Device tree uses obsolete partition map binding: %pOF\n", dp);
nr_parts = plen / sizeof(part[0]);
parts = kcalloc(nr_parts, sizeof(*parts), GFP_KERNEL);
if (!parts)
return -ENOMEM;
names = of_get_property(dp, "partition-names", &plen);
for (i = 0; i < nr_parts; i++) {
parts[i].offset = be32_to_cpu(part->offset);
parts[i].size = be32_to_cpu(part->len) & ~1;
/* bit 0 set signifies read only partition */
if (be32_to_cpu(part->len) & 1)
parts[i].mask_flags = MTD_WRITEABLE;
if (names && (plen > 0)) {
int len = strlen(names) + 1;
parts[i].name = names;
plen -= len;
names += len;
} else {
parts[i].name = "unnamed";
}
part++;
}
*pparts = parts;
return nr_parts;
}
static struct mtd_part_parser ofoldpart_parser = {
.parse_fn = parse_ofoldpart_partitions,
.name = "ofoldpart",
};
static int __init ofpart_parser_init(void)
{
register_mtd_parser(&ofpart_parser);
register_mtd_parser(&ofoldpart_parser);
return 0;
}
static void __exit ofpart_parser_exit(void)
{
deregister_mtd_parser(&ofpart_parser);
deregister_mtd_parser(&ofoldpart_parser);
}
module_init(ofpart_parser_init);
module_exit(ofpart_parser_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Parser for MTD partitioning information in device tree");
MODULE_AUTHOR("Vitaly Wool, David Gibson");
/*
* When MTD core cannot find the requested parser, it tries to load the module
* with the same name. Since we provide the ofoldpart parser, we should have
* the corresponding alias.
*/
MODULE_ALIAS("fixed-partitions");
MODULE_ALIAS("ofoldpart");
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