kernel: backport mtd support for subpartitions in DT
[openwrt/openwrt.git] / target / linux / generic / pending-4.14 / 400-mtd-add-rootfs-split-support.patch
1 From: Felix Fietkau <nbd@nbd.name>
2 Subject: make rootfs split/detection more generic - patch can be moved to generic-2.6 after testing on other platforms
3
4 lede-commit: 328e660b31f0937d52c5ae3d6e7029409918a9df
5 Signed-off-by: Felix Fietkau <nbd@nbd.name>
6 ---
7 drivers/mtd/Kconfig | 17 +++++++++++++++++
8 drivers/mtd/mtdpart.c | 35 +++++++++++++++++++++++++++++++++++
9 include/linux/mtd/partitions.h | 2 ++
10 3 files changed, 54 insertions(+)
11
12 --- a/drivers/mtd/Kconfig
13 +++ b/drivers/mtd/Kconfig
14 @@ -12,6 +12,23 @@ menuconfig MTD
15
16 if MTD
17
18 +menu "OpenWrt specific MTD options"
19 +
20 +config MTD_ROOTFS_ROOT_DEV
21 + bool "Automatically set 'rootfs' partition to be root filesystem"
22 + default y
23 +
24 +config MTD_SPLIT_FIRMWARE
25 + bool "Automatically split firmware partition for kernel+rootfs"
26 + default y
27 +
28 +config MTD_SPLIT_FIRMWARE_NAME
29 + string "Firmware partition name"
30 + depends on MTD_SPLIT_FIRMWARE
31 + default "firmware"
32 +
33 +endmenu
34 +
35 config MTD_TESTS
36 tristate "MTD tests support (DANGEROUS)"
37 depends on m
38 --- a/drivers/mtd/mtdpart.c
39 +++ b/drivers/mtd/mtdpart.c
40 @@ -29,11 +29,13 @@
41 #include <linux/kmod.h>
42 #include <linux/mtd/mtd.h>
43 #include <linux/mtd/partitions.h>
44 +#include <linux/magic.h>
45 #include <linux/of.h>
46 #include <linux/err.h>
47 #include <linux/of.h>
48
49 #include "mtdcore.h"
50 +#include "mtdsplit/mtdsplit.h"
51
52 /* Our partition linked list */
53 static LIST_HEAD(mtd_partitions);
54 @@ -53,6 +55,8 @@ struct mtd_part {
55 struct list_head list;
56 };
57
58 +static void mtd_partition_split(struct mtd_info *master, struct mtd_part *part);
59 +
60 /*
61 * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
62 * the pointer to that structure.
63 @@ -658,6 +662,7 @@ int mtd_add_partition(struct mtd_info *p
64 mutex_unlock(&mtd_partitions_mutex);
65
66 add_mtd_device(&new->mtd);
67 + mtd_partition_split(parent, new);
68
69 mtd_add_partition_attrs(new);
70
71 @@ -736,6 +741,35 @@ int mtd_del_partition(struct mtd_info *m
72 }
73 EXPORT_SYMBOL_GPL(mtd_del_partition);
74
75 +#ifdef CONFIG_MTD_SPLIT_FIRMWARE_NAME
76 +#define SPLIT_FIRMWARE_NAME CONFIG_MTD_SPLIT_FIRMWARE_NAME
77 +#else
78 +#define SPLIT_FIRMWARE_NAME "unused"
79 +#endif
80 +
81 +static void split_firmware(struct mtd_info *master, struct mtd_part *part)
82 +{
83 +}
84 +
85 +void __weak arch_split_mtd_part(struct mtd_info *master, const char *name,
86 + int offset, int size)
87 +{
88 +}
89 +
90 +static void mtd_partition_split(struct mtd_info *master, struct mtd_part *part)
91 +{
92 + static int rootfs_found = 0;
93 +
94 + if (rootfs_found)
95 + return;
96 +
97 + if (!strcmp(part->mtd.name, SPLIT_FIRMWARE_NAME) &&
98 + IS_ENABLED(CONFIG_MTD_SPLIT_FIRMWARE))
99 + split_firmware(master, part);
100 +
101 + arch_split_mtd_part(master, part->mtd.name, part->offset,
102 + part->mtd.size);
103 +}
104 /*
105 * This function, given a master MTD object and a partition table, creates
106 * and registers slave MTD objects which are bound to the master according to
107 @@ -767,6 +801,7 @@ int add_mtd_partitions(struct mtd_info *
108 mutex_unlock(&mtd_partitions_mutex);
109
110 add_mtd_device(&slave->mtd);
111 + mtd_partition_split(master, slave);
112 mtd_add_partition_attrs(slave);
113 /* Look for subpartitions */
114 parse_mtd_partitions(&slave->mtd, parts[i].types, NULL);
115 --- a/include/linux/mtd/partitions.h
116 +++ b/include/linux/mtd/partitions.h
117 @@ -110,5 +110,7 @@ int mtd_add_partition(struct mtd_info *m
118 long long offset, long long length);
119 int mtd_del_partition(struct mtd_info *master, int partno);
120 uint64_t mtd_get_device_size(const struct mtd_info *mtd);
121 +extern void __weak arch_split_mtd_part(struct mtd_info *master,
122 + const char *name, int offset, int size);
123
124 #endif