[openwrt/openwrt] bcm4908: backport mtd parser for Broadcom's U-Boot partition
LEDE Commits
lede-commits at lists.infradead.org
Wed Sep 21 02:14:15 PDT 2022
rmilecki pushed a commit to openwrt/openwrt.git, branch openwrt-21.02:
https://git.openwrt.org/deaad2c8758dcc164478c430696182367611bcbd
commit deaad2c8758dcc164478c430696182367611bcbd
Author: Rafał Miłecki <rafal at milecki.pl>
AuthorDate: Wed Sep 21 10:44:23 2022 +0200
bcm4908: backport mtd parser for Broadcom's U-Boot partition
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 at milecki.pl>
(cherry picked from commit 137149847d0f374515f38952ce0986b03a97f2e4)
---
target/linux/bcm4908/config-5.4 | 1 +
...-mtd-parsers-add-Broadcom-s-U-Boot-parser.patch | 137 +++++++++++++++++++++
2 files changed, 138 insertions(+)
diff --git a/target/linux/bcm4908/config-5.4 b/target/linux/bcm4908/config-5.4
index a11cfc84ac..e051e900df 100644
--- a/target/linux/bcm4908/config-5.4
+++ b/target/linux/bcm4908/config-5.4
@@ -142,6 +142,7 @@ CONFIG_MEMFD_CREATE=y
CONFIG_MFD_SYSCON=y
CONFIG_MIGRATION=y
CONFIG_MODULES_USE_ELF_RELA=y
+CONFIG_MTD_BRCM_U_BOOT=y
CONFIG_MTD_CMDLINE_PARTS=y
CONFIG_MTD_NAND_BRCMNAND=y
CONFIG_MTD_NAND_CORE=y
diff --git a/target/linux/bcm4908/patches-5.4/040-v6.1-mtd-parsers-add-Broadcom-s-U-Boot-parser.patch b/target/linux/bcm4908/patches-5.4/040-v6.1-mtd-parsers-add-Broadcom-s-U-Boot-parser.patch
new file mode 100644
index 0000000000..4d4059b17f
--- /dev/null
+++ b/target/linux/bcm4908/patches-5.4/040-v6.1-mtd-parsers-add-Broadcom-s-U-Boot-parser.patch
@@ -0,0 +1,137 @@
+From 002181f5b150e60c77f21de7ad4dd10e4614cd91 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal at 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 at milecki.pl>
+Signed-off-by: Miquel Raynal <miquel.raynal at 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 at 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");
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