mirror of
https://github.com/openwrt/openwrt.git
synced 2024-12-29 10:08:59 +00:00
deaad2c875
Broadcom's U-Boot contains environment data blocks. They need to be
found (offsets aren't predefined) to access env variables.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
(cherry picked from commit 137149847d)
138 lines
4.1 KiB
Diff
138 lines
4.1 KiB
Diff
From 002181f5b150e60c77f21de7ad4dd10e4614cd91 Mon Sep 17 00:00:00 2001
|
|
From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
|
|
Date: Mon, 11 Jul 2022 17:30:41 +0200
|
|
Subject: [PATCH] mtd: parsers: add Broadcom's U-Boot parser
|
|
MIME-Version: 1.0
|
|
Content-Type: text/plain; charset=UTF-8
|
|
Content-Transfer-Encoding: 8bit
|
|
|
|
Broadcom stores environment variables blocks inside U-Boot partition
|
|
itself. This driver finds & registers them.
|
|
|
|
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
|
|
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
|
|
Link: https://lore.kernel.org/linux-mtd/20220711153041.6036-2-zajec5@gmail.com
|
|
---
|
|
drivers/mtd/parsers/Kconfig | 10 ++++
|
|
drivers/mtd/parsers/Makefile | 1 +
|
|
drivers/mtd/parsers/brcm_u-boot.c | 84 +++++++++++++++++++++++++++++++
|
|
3 files changed, 95 insertions(+)
|
|
create mode 100644 drivers/mtd/parsers/brcm_u-boot.c
|
|
|
|
--- a/drivers/mtd/parsers/Kconfig
|
|
+++ b/drivers/mtd/parsers/Kconfig
|
|
@@ -20,6 +20,16 @@ config MTD_BCM63XX_PARTS
|
|
This provides partition parsing for BCM63xx devices with CFE
|
|
bootloaders.
|
|
|
|
+config MTD_BRCM_U_BOOT
|
|
+ tristate "Broadcom's U-Boot partition parser"
|
|
+ depends on ARCH_BCM4908 || COMPILE_TEST
|
|
+ help
|
|
+ Broadcom uses a custom way of storing U-Boot environment variables.
|
|
+ They are placed inside U-Boot partition itself at unspecified offset.
|
|
+ It's possible to locate them by looking for a custom header with a
|
|
+ magic value. This driver does that and creates subpartitions for
|
|
+ each found environment variables block.
|
|
+
|
|
config MTD_CMDLINE_PARTS
|
|
tristate "Command line partition table parsing"
|
|
depends on MTD
|
|
--- a/drivers/mtd/parsers/Makefile
|
|
+++ b/drivers/mtd/parsers/Makefile
|
|
@@ -2,6 +2,7 @@
|
|
obj-$(CONFIG_MTD_AR7_PARTS) += ar7part.o
|
|
obj-$(CONFIG_MTD_BCM47XX_PARTS) += bcm47xxpart.o
|
|
obj-$(CONFIG_MTD_BCM63XX_PARTS) += bcm63xxpart.o
|
|
+obj-$(CONFIG_MTD_BRCM_U_BOOT) += brcm_u-boot.o
|
|
obj-$(CONFIG_MTD_CMDLINE_PARTS) += cmdlinepart.o
|
|
obj-$(CONFIG_MTD_MYLOADER_PARTS) += myloader.o
|
|
obj-$(CONFIG_MTD_OF_PARTS) += ofpart.o
|
|
--- /dev/null
|
|
+++ b/drivers/mtd/parsers/brcm_u-boot.c
|
|
@@ -0,0 +1,84 @@
|
|
+// SPDX-License-Identifier: GPL-2.0-only
|
|
+/*
|
|
+ * Copyright © 2022 Rafał Miłecki <rafal@milecki.pl>
|
|
+ */
|
|
+
|
|
+#include <linux/module.h>
|
|
+#include <linux/kernel.h>
|
|
+#include <linux/slab.h>
|
|
+#include <linux/mtd/mtd.h>
|
|
+#include <linux/mtd/partitions.h>
|
|
+
|
|
+#define BRCM_U_BOOT_MAX_OFFSET 0x200000
|
|
+#define BRCM_U_BOOT_STEP 0x1000
|
|
+
|
|
+#define BRCM_U_BOOT_MAX_PARTS 2
|
|
+
|
|
+#define BRCM_U_BOOT_MAGIC 0x75456e76 /* uEnv */
|
|
+
|
|
+struct brcm_u_boot_header {
|
|
+ __le32 magic;
|
|
+ __le32 length;
|
|
+} __packed;
|
|
+
|
|
+static const char *names[BRCM_U_BOOT_MAX_PARTS] = {
|
|
+ "u-boot-env",
|
|
+ "u-boot-env-backup",
|
|
+};
|
|
+
|
|
+static int brcm_u_boot_parse(struct mtd_info *mtd,
|
|
+ const struct mtd_partition **pparts,
|
|
+ struct mtd_part_parser_data *data)
|
|
+{
|
|
+ struct brcm_u_boot_header header;
|
|
+ struct mtd_partition *parts;
|
|
+ size_t bytes_read;
|
|
+ size_t offset;
|
|
+ int err;
|
|
+ int i = 0;
|
|
+
|
|
+ parts = kcalloc(BRCM_U_BOOT_MAX_PARTS, sizeof(*parts), GFP_KERNEL);
|
|
+ if (!parts)
|
|
+ return -ENOMEM;
|
|
+
|
|
+ for (offset = 0;
|
|
+ offset < min_t(size_t, mtd->size, BRCM_U_BOOT_MAX_OFFSET);
|
|
+ offset += BRCM_U_BOOT_STEP) {
|
|
+ err = mtd_read(mtd, offset, sizeof(header), &bytes_read, (uint8_t *)&header);
|
|
+ if (err && !mtd_is_bitflip(err)) {
|
|
+ pr_err("Failed to read from %s at 0x%zx: %d\n", mtd->name, offset, err);
|
|
+ continue;
|
|
+ }
|
|
+
|
|
+ if (le32_to_cpu(header.magic) != BRCM_U_BOOT_MAGIC)
|
|
+ continue;
|
|
+
|
|
+ parts[i].name = names[i];
|
|
+ parts[i].offset = offset;
|
|
+ parts[i].size = sizeof(header) + le32_to_cpu(header.length);
|
|
+ i++;
|
|
+ pr_info("offset:0x%zx magic:0x%08x BINGO\n", offset, header.magic);
|
|
+
|
|
+ if (i == BRCM_U_BOOT_MAX_PARTS)
|
|
+ break;
|
|
+ }
|
|
+
|
|
+ *pparts = parts;
|
|
+
|
|
+ return i;
|
|
+};
|
|
+
|
|
+static const struct of_device_id brcm_u_boot_of_match_table[] = {
|
|
+ { .compatible = "brcm,u-boot" },
|
|
+ {},
|
|
+};
|
|
+MODULE_DEVICE_TABLE(of, brcm_u_boot_of_match_table);
|
|
+
|
|
+static struct mtd_part_parser brcm_u_boot_mtd_parser = {
|
|
+ .parse_fn = brcm_u_boot_parse,
|
|
+ .name = "brcm_u-boot",
|
|
+ .of_match_table = brcm_u_boot_of_match_table,
|
|
+};
|
|
+module_mtd_part_parser(brcm_u_boot_mtd_parser);
|
|
+
|
|
+MODULE_LICENSE("GPL");
|