kernel: mtdsplit: bcm_wfi: support Sercomm bootflags

Sercomm uses 2 bootflag partitions and boots the firmware with the highest
bootflag. Support splitting the firmware partition while keeping support for
unsplitted layout.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>

diff --git a/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_bcm_wfi.c b/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_bcm_wfi.c
index f99685c8e6f3378b4b76517e8e35fc4b743b6986..7eb6526f9e4595d28d6d227b4eb4ab921c91cd47 100644 (file)
--- a/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_bcm_wfi.c
+++ b/target/linux/generic/files/drivers/mtd/mtdsplit/mtdsplit_bcm_wfi.c
@@ -24,6 +24,8 @@
 
 #include "mtdsplit.h"
 
+#define char_to_num(c)         ((c >= '0' && c <= '9') ? (c - '0') : (0))
+
 #define BCM_WFI_PARTS          3
 
 #define CFERAM_NAME            "cferam"
@@ -35,6 +37,11 @@
 
 #define UBI_MAGIC              0x55424923
 
+#define SERCOMM_MAGIC_PFX      "eRcOmM."
+#define SERCOMM_MAGIC_PFX_LEN  (sizeof(SERCOMM_MAGIC_PFX) - 1)
+#define SERCOMM_MAGIC          "eRcOmM.000"
+#define SERCOMM_MAGIC_LEN      (sizeof(SERCOMM_MAGIC) - 1)
+
 static u32 jffs2_dirent_crc(struct jffs2_raw_dirent *node)
 {
        return crc32(0, node, sizeof(struct jffs2_raw_dirent) - 8);
@@ -220,9 +227,150 @@ static struct mtd_part_parser mtdsplit_bcm_wfi_parser = {
        .type = MTD_PARSER_TYPE_FIRMWARE,
 };
 
+static int sercomm_bootflag_value(struct mtd_info *mtd, uint8_t *buf)
+{
+       size_t retlen;
+       loff_t offs;
+       int rc;
+
+       for (offs = 0; offs < mtd->size; offs += mtd->erasesize) {
+               rc = mtd_read(mtd, offs, SERCOMM_MAGIC_LEN, &retlen, buf);
+               if (rc || retlen != SERCOMM_MAGIC_LEN)
+                       continue;
+
+               if (memcmp(buf, SERCOMM_MAGIC_PFX, SERCOMM_MAGIC_PFX_LEN))
+                       continue;
+
+               rc = char_to_num(buf[SERCOMM_MAGIC_PFX_LEN + 0]) * 100;
+               rc += char_to_num(buf[SERCOMM_MAGIC_PFX_LEN + 1]) * 10;
+               rc += char_to_num(buf[SERCOMM_MAGIC_PFX_LEN + 2]) * 1;
+
+               return rc;
+       }
+
+       return -ENOENT;
+}
+
+static int mtdsplit_parse_ser_wfi(struct mtd_info *master,
+                                 const struct mtd_partition **pparts,
+                                 struct mtd_part_parser_data *data)
+{
+       struct mtd_info *mtd_bf1, *mtd_bf2;
+       struct erase_info bf_erase;
+       struct mtd_partition *parts;
+       loff_t kernel_off, rootfs_off, img_size;
+       loff_t img2_off, img2_size = 0;
+       unsigned int num_parts = BCM_WFI_PARTS, cur_part = 0;
+       uint8_t *buf;
+       int bf1, bf2;
+       int ret;
+
+       mtd_bf1 = get_mtd_device_nm("bootflag1");
+       if (IS_ERR(mtd_bf1))
+               return -ENOENT;
+
+       mtd_bf2 = get_mtd_device_nm("bootflag2");
+       if (IS_ERR(mtd_bf2))
+               return -ENOENT;
+
+       buf = kzalloc(master->erasesize, GFP_KERNEL);
+       if (!buf)
+               return -ENOMEM;
+
+       bf1 = sercomm_bootflag_value(mtd_bf1, buf);
+       if (bf1 >= 0)
+               printk("sercomm: bootflag1=%d\n", bf1);
+
+       bf2 = sercomm_bootflag_value(mtd_bf2, buf);
+       if (bf2 >= 0)
+               printk("sercomm: bootflag2=%d\n", bf2);
+
+       if (bf1 == bf2 && bf2 >= 0) {
+               bf2 = -ENOENT;
+               bf_erase.addr = 0;
+               bf_erase.len = mtd_bf2->size;
+               mtd_erase(mtd_bf2, &bf_erase);
+       }
+
+       if (bf1 >= bf2) {
+               kernel_off = 0;
+               if (bf2 >= 0) {
+                       img_size = master->size / 2;
+
+                       img2_off = img_size;
+                       img2_size = master->size - img2_off;
+                       num_parts++;
+               } else {
+                       img_size = master->size;
+               }
+       } else {
+               kernel_off = master->size / 2;
+               img_size = master->size;
+
+               img2_off = 0;
+               img2_size = kernel_off;
+               num_parts++;
+       }
+
+       ret = jffs2_find_file(master, buf, KERNEL_NAME, KERNEL_NAME_LEN,
+                             &kernel_off, img_size);
+       kfree(buf);
+       if (ret)
+               return ret;
+
+       rootfs_off = kernel_off + master->erasesize;
+       ret = ubifs_find(master, &rootfs_off, img_size);
+       if (ret)
+               return ret;
+
+       parts = kzalloc(num_parts * sizeof(*parts), GFP_KERNEL);
+       if (!parts)
+               return -ENOMEM;
+
+       parts[cur_part].name = "firmware";
+       parts[cur_part].offset = kernel_off;
+       parts[cur_part].size = img_size - kernel_off;
+       cur_part++;
+
+       parts[cur_part].name = KERNEL_PART_NAME;
+       parts[cur_part].offset = kernel_off;
+       parts[cur_part].size = rootfs_off - kernel_off;
+       cur_part++;
+
+       parts[cur_part].name = UBI_PART_NAME;
+       parts[cur_part].offset = rootfs_off;
+       parts[cur_part].size = img_size - rootfs_off;
+       cur_part++;
+
+       if (img2_size) {
+               parts[cur_part].name = "img2";
+               parts[cur_part].offset = img2_off;
+               parts[cur_part].size = img2_size;
+               cur_part++;
+       }
+
+       *pparts = parts;
+
+       return num_parts;
+}
+
+static const struct of_device_id mtdsplit_ser_wfi_of_match[] = {
+       { .compatible = "sercomm,wfi" },
+       { },
+};
+
+static struct mtd_part_parser mtdsplit_ser_wfi_parser = {
+       .owner = THIS_MODULE,
+       .name = "ser-wfi-fw",
+       .of_match_table = mtdsplit_ser_wfi_of_match,
+       .parse_fn = mtdsplit_parse_ser_wfi,
+       .type = MTD_PARSER_TYPE_FIRMWARE,
+};
+
 static int __init mtdsplit_bcm_wfi_init(void)
 {
        register_mtd_parser(&mtdsplit_bcm_wfi_parser);
+       register_mtd_parser(&mtdsplit_ser_wfi_parser);
 
        return 0;
 }