openwrt/target/linux/generic/pending-4.9/161-mtd-part-add-generic-parsing-of-linux-part-probe.patch
Rafał Miłecki 2a598bbaa3 kernel: backport mtd support for subpartitions in DT
This is a new & warm feature that allows nesting partiitons in DT and
mixing their types (e.g. static vs. dynamic). It's very useful for
boards that have most partitions static but some of them require extra
parsing (e.g. a "firmware" partition).

It's required to successfully backport support for new devices using
that new syntax in their DT files.

Since brcm63xx has a custom alternative patch the upstream one is being
reverted for it. The plan is to make brcm63xx use the upstream
implementation.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
2018-07-27 22:16:24 +02:00

182 lines
5.0 KiB
Diff

From: Hauke Mehrtens <hauke@hauke-m.de>
Subject: mtd: part: add generic parsing of linux,part-probe
This moves the linux,part-probe device tree parsing code from
physmap_of.c to mtdpart.c. Now all drivers can use this feature by just
providing a reference to their device tree node in struct
mtd_part_parser_data.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
---
Documentation/devicetree/bindings/mtd/nand.txt | 16 +++++++++
drivers/mtd/maps/physmap_of.c | 46 +-------------------------
drivers/mtd/mtdpart.c | 45 +++++++++++++++++++++++++
3 files changed, 62 insertions(+), 45 deletions(-)
--- a/Documentation/devicetree/bindings/mtd/nand.txt
+++ b/Documentation/devicetree/bindings/mtd/nand.txt
@@ -44,6 +44,22 @@ Optional NAND chip properties:
used by the upper layers, and you want to make your NAND
as reliable as possible.
+- linux,part-probe: list of name as strings of the partition parser
+ which should be used to parse the partition table.
+ They will be tried in the specified ordering and
+ the next one will be used if the previous one
+ failed.
+
+ Example: linux,part-probe = "cmdlinepart", "ofpart";
+
+ This is also the default value, which will be used
+ if this attribute is not specified. It could be
+ that the flash driver in use overwrote the default
+ value and uses some other default.
+
+ Possible values are: bcm47xxpart, afs, ar7part,
+ ofoldpart, ofpart, bcm63xxpart, RedBoot, cmdlinepart
+
The ECC strength and ECC step size properties define the correction capability
of a controller. Together, they say a controller can correct "{strength} bit
errors per {size} bytes".
--- a/drivers/mtd/maps/physmap_of.c
+++ b/drivers/mtd/maps/physmap_of.c
@@ -113,47 +113,9 @@ static struct mtd_info *obsolete_probe(s
static const char * const part_probe_types_def[] = {
"cmdlinepart", "RedBoot", "ofpart", "ofoldpart", NULL };
-static const char * const *of_get_probes(struct device_node *dp)
-{
- const char *cp;
- int cplen;
- unsigned int l;
- unsigned int count;
- const char **res;
-
- cp = of_get_property(dp, "linux,part-probe", &cplen);
- if (cp == NULL)
- return part_probe_types_def;
-
- count = 0;
- for (l = 0; l != cplen; l++)
- if (cp[l] == 0)
- count++;
-
- res = kzalloc((count + 1)*sizeof(*res), GFP_KERNEL);
- if (!res)
- return NULL;
- count = 0;
- while (cplen > 0) {
- res[count] = cp;
- l = strlen(cp) + 1;
- cp += l;
- cplen -= l;
- count++;
- }
- return res;
-}
-
-static void of_free_probes(const char * const *probes)
-{
- if (probes != part_probe_types_def)
- kfree(probes);
-}
-
static const struct of_device_id of_flash_match[];
static int of_flash_probe(struct platform_device *dev)
{
- const char * const *part_probe_types;
const struct of_device_id *match;
struct device_node *dp = dev->dev.of_node;
struct resource res;
@@ -317,14 +279,8 @@ static int of_flash_probe(struct platfor
info->cmtd->dev.parent = &dev->dev;
mtd_set_of_node(info->cmtd, dp);
- part_probe_types = of_get_probes(dp);
- if (!part_probe_types) {
- err = -ENOMEM;
- goto err_out;
- }
- mtd_device_parse_register(info->cmtd, part_probe_types, NULL,
+ mtd_device_parse_register(info->cmtd, part_probe_types_def, NULL,
NULL, 0);
- of_free_probes(part_probe_types);
kfree(mtd_list);
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -29,6 +29,7 @@
#include <linux/kmod.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
+#include <linux/of.h>
#include <linux/err.h>
#include <linux/of.h>
@@ -827,6 +828,42 @@ void deregister_mtd_parser(struct mtd_pa
EXPORT_SYMBOL_GPL(deregister_mtd_parser);
/*
+ * Parses the linux,part-probe device tree property.
+ * When a non null value is returned it has to be freed with kfree() by
+ * the caller.
+ */
+static const char * const *of_get_probes(struct device_node *dp)
+{
+ const char *cp;
+ int cplen;
+ unsigned int l;
+ unsigned int count;
+ const char **res;
+
+ cp = of_get_property(dp, "linux,part-probe", &cplen);
+ if (cp == NULL)
+ return NULL;
+
+ count = 0;
+ for (l = 0; l != cplen; l++)
+ if (cp[l] == 0)
+ count++;
+
+ res = kzalloc((count + 1) * sizeof(*res), GFP_KERNEL);
+ if (!res)
+ return NULL;
+ count = 0;
+ while (cplen > 0) {
+ res[count] = cp;
+ l = strlen(cp) + 1;
+ cp += l;
+ cplen -= l;
+ count++;
+ }
+ return res;
+}
+
+/*
* Do not forget to update 'parse_mtd_partitions()' kerneldoc comment if you
* are changing this array!
*/
@@ -975,6 +1012,13 @@ int parse_mtd_partitions(struct mtd_info
struct mtd_partitions pparts = { };
struct mtd_part_parser *parser;
int ret, err = 0;
+ const char *const *types_of = NULL;
+
+ if (mtd_get_of_node(master)) {
+ types_of = of_get_probes(mtd_get_of_node(master));
+ if (types_of != NULL)
+ types = types_of;
+ }
if (!types)
types = mtd_is_partition(master) ? default_subpartition_types :
@@ -1016,6 +1060,7 @@ int parse_mtd_partitions(struct mtd_info
if (ret < 0 && !err)
err = ret;
}
+ kfree(types_of);
return err;
}