--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* a mtdsplit driver for IIJ SEIL devices */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/of.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/byteorder/generic.h>
+
+#include "mtdsplit.h"
+
+#define NR_PARTS 2
+#define SEIL_VFMT 1
+#define LDR_ENV_PART_NAME "bootloader-env"
+#define LDR_ENV_KEY_BOOTDEV "BOOTDEV"
+
+struct seil_header {
+ uint64_t id; /* Identifier */
+ uint8_t copy[80]; /* Copyright */
+ uint32_t dcrc; /* Data CRC Checksum */
+ uint32_t vfmt; /* Image Version Format */
+ uint32_t vmjr; /* Image Version Major */
+ uint32_t vmnr; /* Image Version Minor */
+ uint8_t vrel[32]; /* Image Version Release */
+ uint32_t dxor; /* xor value for Data? */
+ uint32_t dlen; /* Data Length */
+};
+
+/*
+ * check whether the current mtd device is active or not
+ *
+ * example of BOOTDEV value (IIJ SA-W2):
+ * - "flash" : primary image on flash
+ * - "rescue" : secondary image on flash
+ * - "usb" : usb storage
+ * - "lan0/1" : network
+ */
+static bool seil_bootdev_is_active(struct device_node *np)
+{
+ struct mtd_info *env_mtd;
+ char *buf, *var, *value, *eq;
+ const char *devnm;
+ size_t rdlen;
+ int ret;
+
+ /*
+ * read bootdev name of the partition
+ * if doesn't exist, return true and skip checking of active device
+ */
+ ret = of_property_read_string(np, "iij,bootdev-name", &devnm);
+ if (ret == -EINVAL)
+ return true;
+ else if (ret < 0)
+ return false;
+
+ env_mtd = get_mtd_device_nm(LDR_ENV_PART_NAME);
+ if (IS_ERR(env_mtd)) {
+ pr_err("failed to get mtd device \"%s\"", LDR_ENV_PART_NAME);
+ return false;
+ }
+
+ buf = vmalloc(env_mtd->size);
+ if (!buf)
+ return false;
+
+ ret = mtd_read(env_mtd, 0, env_mtd->size, &rdlen, buf);
+ if (ret || rdlen != env_mtd->size) {
+ pr_err("failed to read from mtd (%d)\n", ret);
+ ret = 0;
+ goto exit_vfree;
+ }
+
+ for (var = buf, ret = false;
+ var < buf + env_mtd->size && *var;
+ var = value + strlen(value) + 1) {
+ eq = strchr(var, '=');
+ if (!eq)
+ break;
+ *eq = '\0';
+ value = eq + 1;
+
+ pr_debug("ENV: %s=%s\n", var, value);
+ if (!strcmp(var, LDR_ENV_KEY_BOOTDEV)) {
+ ret = !strcmp(devnm, value);
+ break;
+ }
+ }
+
+exit_vfree:
+ vfree(buf);
+
+ return ret;
+}
+
+static int mtdsplit_parse_seil_fw(struct mtd_info *master,
+ const struct mtd_partition **pparts,
+ struct mtd_part_parser_data *data)
+{
+ struct device_node *np = mtd_get_of_node(master);
+ struct mtd_partition *parts;
+ struct seil_header header;
+ size_t image_size = 0;
+ size_t rootfs_offset;
+ size_t hdrlen = sizeof(header);
+ size_t retlen;
+ int ret;
+ u64 id;
+
+ if (!seil_bootdev_is_active(np))
+ return -ENODEV;
+
+ ret = of_property_read_u64(np, "iij,seil-id", &id);
+ if (ret) {
+ pr_err("failed to get iij,seil-id from dt\n");
+ return ret;
+ }
+ pr_debug("got seil-id=0x%016llx from dt\n", id);
+
+ parts = kcalloc(NR_PARTS, sizeof(*parts), GFP_KERNEL);
+ if (!parts)
+ return -ENOMEM;
+
+ ret = mtd_read(master, 0, hdrlen, &retlen, (void *)&header);
+ if (ret)
+ goto err_free_parts;
+
+ if (retlen != hdrlen) {
+ ret = -EIO;
+ goto err_free_parts;
+ }
+
+ if (be64_to_cpu(header.id) != id ||
+ be32_to_cpu(header.vfmt) != SEIL_VFMT) {
+ pr_debug("no valid seil image found in \"%s\"\n", master->name);
+ ret = -ENODEV;
+ goto err_free_parts;
+ }
+
+ image_size = hdrlen + be32_to_cpu(header.dlen);
+ if (image_size > master->size) {
+ pr_err("seil image exceeds MTD device \"%s\"\n", master->name);
+ ret = -EINVAL;
+ goto err_free_parts;
+ }
+
+ /* find the roots after the seil image */
+ ret = mtd_find_rootfs_from(master, image_size,
+ master->size, &rootfs_offset, NULL);
+ if (ret || (master->size - rootfs_offset) == 0) {
+ pr_debug("no rootfs after seil image in \"%s\"\n",
+ master->name);
+ ret = -ENODEV;
+ goto err_free_parts;
+ }
+
+ parts[0].name = KERNEL_PART_NAME;
+ parts[0].offset = 0;
+ parts[0].size = rootfs_offset;
+
+ parts[1].name = ROOTFS_PART_NAME;
+ parts[1].offset = rootfs_offset;
+ parts[1].size = master->size - rootfs_offset;
+
+ *pparts = parts;
+ return NR_PARTS;
+
+err_free_parts:
+ kfree(parts);
+ return ret;
+}
+
+static const struct of_device_id mtdsplit_seil_fw_of_match_table[] = {
+ { .compatible = "iij,seil-firmware" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, mtdsplit_seil_fw_of_match_table);
+
+static struct mtd_part_parser mtdsplit_seil_fw_parser = {
+ .owner = THIS_MODULE,
+ .name = "seil-fw",
+ .of_match_table = mtdsplit_seil_fw_of_match_table,
+ .parse_fn = mtdsplit_parse_seil_fw,
+ .type = MTD_PARSER_TYPE_FIRMWARE,
+};
+
+module_mtd_part_parser(mtdsplit_seil_fw_parser);
projects / openwrt / staging / stintel.git / commitdiff