ath25: add back target support

Discussion on the mailing list reveals that this target has active
users. As we are finally able to upgrade this target to kernel 5.4,
add it back to master.

This reverts commit 7d29a5571403 ("ath25: drop target") and
immediately moves the relevant files to 5.4, without touching
the content.

Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>

1 files changed, 60 insertions, 0 deletions

diff --git a/target/linux/ath25/patches-5.4/140-redboot_boardconfig.patch b/target/linux/ath25/patches-5.4/140-redboot_boardconfig.patch
new file mode 100644
index 0000000000..6aad761cb1
--- /dev/null
+++ b/target/linux/ath25/patches-5.4/140-redboot_boardconfig.patch
@@ -0,0 +1,60 @@
+--- a/drivers/mtd/redboot.c
++++ b/drivers/mtd/redboot.c
+@@ -30,6 +30,8 @@
+ #include <linux/mtd/partitions.h>
+ #include <linux/module.h>
+ 
++#define BOARD_CONFIG_PART		"boardconfig"
++
+ struct fis_image_desc {
+     unsigned char name[16];      // Null terminated name
+     uint32_t	  flash_base;    // Address within FLASH of image
+@@ -60,6 +62,7 @@ static int parse_redboot_partitions(stru
+ 				    const struct mtd_partition **pparts,
+ 				    struct mtd_part_parser_data *data)
+ {
++	unsigned long max_offset = 0;
+ 	int nrparts = 0;
+ 	struct fis_image_desc *buf;
+ 	struct mtd_partition *parts;
+@@ -225,14 +228,15 @@ static int parse_redboot_partitions(stru
+ 		}
+ 	}
+ #endif
+-	parts = kzalloc(sizeof(*parts)*nrparts + nulllen + namelen, GFP_KERNEL);
++	parts = kzalloc(sizeof(*parts) * (nrparts + 1) + nulllen + namelen +
++			sizeof(BOARD_CONFIG_PART), GFP_KERNEL);
+ 
+ 	if (!parts) {
+ 		ret = -ENOMEM;
+ 		goto out;
+ 	}
+ 
+-	nullname = (char *)&parts[nrparts];
++	nullname = (char *)&parts[nrparts + 1];
+ #ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
+ 	if (nulllen > 0) {
+ 		strcpy(nullname, nullstring);
+@@ -251,6 +255,8 @@ static int parse_redboot_partitions(stru
+ 	}
+ #endif
+ 	for ( ; i<nrparts; i++) {
++		if (max_offset < buf[i].flash_base + buf[i].size)
++			max_offset = buf[i].flash_base + buf[i].size;
+ 		parts[i].size = fl->img->size;
+ 		parts[i].offset = fl->img->flash_base;
+ 		parts[i].name = names;
+@@ -284,6 +290,13 @@ static int parse_redboot_partitions(stru
+ 		fl = fl->next;
+ 		kfree(tmp_fl);
+ 	}
++	if (master->size - max_offset >= master->erasesize) {
++		parts[nrparts].size = master->size - max_offset;
++		parts[nrparts].offset = max_offset;
++		parts[nrparts].name = names;
++		strcpy(names, BOARD_CONFIG_PART);
++		nrparts++;
++	}
+ 	ret = nrparts;
+ 	*pparts = parts;
+  out: