Android documentation recommends new image format for storing DTB/DTBO files: [1]. To support that format, two things should be done:
1. Add dt_table.h file from Android (BSD-3 relicensed version): [2]. This header defines structures and constants that we need to work with that DT image format.
Changes: - re-licensed from Apache to BSD-3 - removed functions declarations - change the coding style to kernel (make checkpatch happy)
2. Add helper functions for Android DTB/DTBO format. In image-android-dt.* files you can find helper functions to work with Android DT image format, such us routines for: - printing the dump of image structure - getting the address and size of desired dtb/dtbo file
[1] https://source.android.com/devices/architecture/dto/partitions [2] https://android.googlesource.com/platform/system/libufdt/+/58a7582180f477032...
Signed-off-by: Sam Protsenko semen.protsenko@linaro.org --- common/image-android-dt.c | 134 +++++++++++++++++++++++++++++++++++++ include/dt_table.h | 46 +++++++++++++ include/image-android-dt.h | 18 +++++ 3 files changed, 198 insertions(+) create mode 100644 common/image-android-dt.c create mode 100644 include/dt_table.h create mode 100644 include/image-android-dt.h
diff --git a/common/image-android-dt.c b/common/image-android-dt.c new file mode 100644 index 0000000000..f218db06bb --- /dev/null +++ b/common/image-android-dt.c @@ -0,0 +1,134 @@ +/* + * (C) Copyright 2018 Linaro Ltd. + * Sam Protsenko semen.protsenko@linaro.org + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <image-android-dt.h> +#include <common.h> +#include <linux/libfdt_env.h> +#include <linux/libfdt.h> + +/** + * Check if image header is correct. + * + * @param hdr Address to image header + * @return true if header is correct or false if header is incorrect + */ +bool android_dt_check_header(const struct dt_table_header *hdr) +{ + return fdt32_to_cpu(hdr->magic) == DT_TABLE_MAGIC; +} + +/** + * Get the address of FDT (dtb or dtbo) in memory by its index in image. + * + * @param hdr Address to image header + * @param index Index of desired FDT in image (starting from 0) + * @param[out] addr If not null, will contain address to specified FDT + * @param[out] size If not NULL, will contain size of specified FDT + * + * @return true on success or false on error + */ +bool android_dt_get_fdt_by_index(const struct dt_table_header *hdr, + u32 index, ulong *addr, u32 *size) +{ + const struct dt_table_entry *e; + u32 entry_count = fdt32_to_cpu(hdr->dt_entry_count); + u32 entries_offset = fdt32_to_cpu(hdr->dt_entries_offset); + u32 entry_size = fdt32_to_cpu(hdr->dt_entry_size); + u32 dt_offset, dt_size; + + if (index > entry_count) { + printf("Error: index > dt_entry_count (%u > %u)\n", index, + entry_count); + return false; + } + + e = (const struct dt_table_entry *)((ulong)hdr + entries_offset + + index * entry_size); + dt_offset = fdt32_to_cpu(e->dt_offset); + dt_size = fdt32_to_cpu(e->dt_size); + + if (addr) + *addr = ((ulong)hdr + dt_offset); + if (size) + *size = dt_size; + + return true; +} + +#if !defined(CONFIG_SPL_BUILD) +static void android_dt_print_fdt_info(const struct fdt_header *fdt) +{ + u32 fdt_size; + int root_node_off; + const char *compatible = NULL; + + fdt_size = fdt_totalsize(fdt); + root_node_off = fdt_path_offset(fdt, "/"); + if (root_node_off < 0) { + printf("Error: Root node not found\n"); + } else { + compatible = fdt_getprop(fdt, root_node_off, "compatible", + NULL); + } + + printf(" (FDT)size = %d\n", fdt_size); + printf(" (FDT)compatible = %s\n", + compatible ? compatible : "(unknown)"); +} + +/** + * Print information about DT image structure. + * + * @param hdr Address to image header + */ +void android_dt_print_contents(const struct dt_table_header *hdr) +{ + u32 i; + u32 entry_count = fdt32_to_cpu(hdr->dt_entry_count); + u32 entries_offset = fdt32_to_cpu(hdr->dt_entries_offset); + u32 entry_size = fdt32_to_cpu(hdr->dt_entry_size); + + /* Print image header info */ + printf("dt_table_header:\n"); + printf(" magic = %08x\n", fdt32_to_cpu(hdr->magic)); + printf(" total_size = %d\n", fdt32_to_cpu(hdr->total_size)); + printf(" header_size = %d\n", fdt32_to_cpu(hdr->header_size)); + printf(" dt_entry_size = %d\n", entry_size); + printf(" dt_entry_count = %d\n", entry_count); + printf(" dt_entries_offset = %d\n", entries_offset); + printf(" page_size = %d\n", fdt32_to_cpu(hdr->page_size)); + printf(" reserved[0] = %08x\n", fdt32_to_cpu(hdr->reserved[0])); + + /* Print image entries info */ + for (i = 0; i < entry_count; ++i) { + const struct dt_table_entry *e; + const struct fdt_header *fdt; + u32 dt_offset, dt_size; + u32 j; + + e = (const struct dt_table_entry *)((ulong)hdr + entries_offset + + i * entry_size); + dt_offset = fdt32_to_cpu(e->dt_offset); + dt_size = fdt32_to_cpu(e->dt_size); + + printf("dt_table_entry[%d]:\n", i); + printf(" dt_size = %d\n", dt_size); + printf(" dt_offset = %d\n", dt_offset); + printf(" id = %08x\n", fdt32_to_cpu(e->id)); + printf(" rev = %08x\n", fdt32_to_cpu(e->rev)); + + for (j = 0; j < 4; ++j) { + printf(" custom[%d] = %08x\n", j, + fdt32_to_cpu(e->custom[j])); + } + + /* Print FDT info for this entry */ + fdt = (const struct fdt_header *)((ulong)hdr + dt_offset); + android_dt_print_fdt_info(fdt); + } +} +#endif diff --git a/include/dt_table.h b/include/dt_table.h new file mode 100644 index 0000000000..19cbbeab2a --- /dev/null +++ b/include/dt_table.h @@ -0,0 +1,46 @@ +/* + * This is from the Android Project, + * Repository: https://android.googlesource.com/platform/system/libufdt + * File: utils/src/dt_table.h + * Commit: 58a7582180f477032cd6c74f8d9afad0038e74c3 + * Copyright (C) 2017 The Android Open Source Project + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#ifndef DT_TABLE_H +#define DT_TABLE_H + +#include <linux/types.h> + +#define DT_TABLE_MAGIC 0xd7b7ab1e +#define DT_TABLE_DEFAULT_PAGE_SIZE 2048 + +struct dt_table_header { + u32 magic; /* DT_TABLE_MAGIC */ + u32 total_size; /* includes dt_table_header + all dt_table_entry + * and all dtb/dtbo + */ + u32 header_size; /* sizeof(dt_table_header) */ + + u32 dt_entry_size; /* sizeof(dt_table_entry) */ + u32 dt_entry_count; /* number of dt_table_entry */ + u32 dt_entries_offset; /* offset to the first dt_table_entry + * from head of dt_table_header. + * The value will be equal to header_size if + * no padding is appended + */ + u32 page_size; /* flash page size we assume */ + u32 reserved[1]; /* must be zero */ +}; + +struct dt_table_entry { + u32 dt_size; + u32 dt_offset; /* offset from head of dt_table_header */ + + u32 id; /* optional, must be zero if unused */ + u32 rev; /* optional, must be zero if unused */ + u32 custom[4]; /* optional, must be zero if unused */ +}; + +#endif diff --git a/include/image-android-dt.h b/include/image-android-dt.h new file mode 100644 index 0000000000..f9b5ff3f13 --- /dev/null +++ b/include/image-android-dt.h @@ -0,0 +1,18 @@ +/* + * (C) Copyright 2018 Linaro Ltd. + * Sam Protsenko semen.protsenko@linaro.org + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef IMAGE_ANDROID_DT_H +#define IMAGE_ANDROID_DT_H + +#include <dt_table.h> + +bool android_dt_check_header(const struct dt_table_header *hdr); +void android_dt_print_contents(const struct dt_table_header *hdr); +bool android_dt_get_fdt_by_index(const struct dt_table_header *hdr, + u32 index, ulong *addr, u32 *size); + +#endif /* IMAGE_ANDROID_DT_H */