From 137149847d0f374515f38952ce0986b03a97f2e4 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Rafa=C5=82=20Mi=C5=82ecki?= Date: Tue, 20 Sep 2022 22:34:27 +0200 Subject: [PATCH] bcm4908: backport mtd parser for Broadcom's U-Boot partition MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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 --- target/linux/bcm4908/config-5.10 | 1 + ...parsers-add-Broadcom-s-U-Boot-parser.patch | 137 ++++++++++++++++++ 2 files changed, 138 insertions(+) create mode 100644 target/linux/bcm4908/patches-5.10/040-v6.1-mtd-parsers-add-Broadcom-s-U-Boot-parser.patch diff --git a/target/linux/bcm4908/config-5.10 b/target/linux/bcm4908/config-5.10 index 4009f800386..762ce49eeb8 100644 --- a/target/linux/bcm4908/config-5.10 +++ b/target/linux/bcm4908/config-5.10 @@ -133,6 +133,7 @@ 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-5.10/040-v6.1-mtd-parsers-add-Broadcom-s-U-Boot-parser.patch b/target/linux/bcm4908/patches-5.10/040-v6.1-mtd-parsers-add-Broadcom-s-U-Boot-parser.patch new file mode 100644 index 00000000000..4d4059b17f1 --- /dev/null +++ b/target/linux/bcm4908/patches-5.10/040-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?= +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 +Signed-off-by: Miquel Raynal +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 ++ */ ++ ++#include ++#include ++#include ++#include ++#include ++ ++#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"); -- 2.30.2