[U-Boot] [PATCH v2 1/2] common: Add support for Android DT image
Alex Deymo
deymo+ at google.com
Tue May 8 15:32:18 UTC 2018
Le jeu. 19 avr. 2018 à 22:52, Sam Protsenko <semen.protsenko at linaro.org> a
écrit :
> 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
>
I'm not familiar with how you handle these re-licensing so I can't say
anything about that.
> - removed functions declarations
>
You also removed DT_TABLE_DEFAULT_VERSION but left
DT_TABLE_DEFAULT_PAGE_SIZE, was that intentional?
- 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/+/58a7582180f477032cd6c74f8d9afad0038e74c3/utils/src/dt_table.h
>
> Signed-off-by: Sam Protsenko <semen.protsenko at linaro.org>
> ---
> common/image-android-dt.c | 157 +++++++++++++++++++++++++++++++++++++
> include/dt_table.h | 46 +++++++++++
> include/image-android-dt.h | 21 +++++
> 3 files changed, 224 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..9b7683faab
> --- /dev/null
> +++ b/common/image-android-dt.c
> @@ -0,0 +1,157 @@
> +/*
> + * (C) Copyright 2018 Linaro Ltd.
> + * Sam Protsenko <semen.protsenko at linaro.org>
> + *
> + * SPDX-License-Identifier: GPL-2.0+
> + */
> +
> +#include <image-android-dt.h>
> +#include <dt_table.h>
> +#include <common.h>
> +#include <linux/libfdt.h>
> +#include <mapmem.h>
> +
> +/**
> + * Check if image header is correct.
> + *
> + * @param hdr_addr Start address of DT image
> + * @return true if header is correct or false if header is incorrect
> + */
> +bool android_dt_check_header(ulong hdr_addr)
> +{
> + const struct dt_table_header *hdr;
> + u32 magic;
> +
> + hdr = map_sysmem(hdr_addr, sizeof(*hdr));
> + magic = fdt32_to_cpu(hdr->magic);
> + unmap_sysmem(hdr);
> +
> + return magic == DT_TABLE_MAGIC;
> +}
> +
> +/**
> + * Get the address of FDT (dtb or dtbo) in memory by its index in image.
> + *
> + * @param hdr_addr Start address of DT image
> + * @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(ulong hdr_addr, u32 index, ulong *addr,
> + u32 *size)
> +{
> + const struct dt_table_header *hdr;
> + const struct dt_table_entry *e;
> + u32 entry_count, entries_offset, entry_size;
> + ulong e_addr;
> + u32 dt_offset, dt_size;
> +
> + hdr = map_sysmem(hdr_addr, sizeof(*hdr));
> + entry_count = fdt32_to_cpu(hdr->dt_entry_count);
> + entries_offset = fdt32_to_cpu(hdr->dt_entries_offset);
> + entry_size = fdt32_to_cpu(hdr->dt_entry_size);
> + unmap_sysmem(hdr);
> +
> + if (index > entry_count) {
> + printf("Error: index > dt_entry_count (%u > %u)\n", index,
> + entry_count);
> + return false;
> + }
>
This function assumes the image is valid in several places, but here you
could also check that the relative offset you are going to load falls
within the the fdt32_to_cpu(hdr->total_size).
+
> + e_addr = hdr_addr + entries_offset + index * entry_size;
> + e = map_sysmem(e_addr, sizeof(*e));
> + dt_offset = fdt32_to_cpu(e->dt_offset);
> + dt_size = fdt32_to_cpu(e->dt_size);
> + unmap_sysmem(e);
> +
> + if (addr)
> + *addr = hdr_addr + 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_addr Start address of DT image
> + */
> +void android_dt_print_contents(ulong hdr_addr)
> +{
> + const struct dt_table_header *hdr;
> + u32 entry_count, entries_offset, entry_size;
> + u32 i;
> +
> + hdr = map_sysmem(hdr_addr, sizeof(*hdr));
> + entry_count = fdt32_to_cpu(hdr->dt_entry_count);
> + entries_offset = fdt32_to_cpu(hdr->dt_entries_offset);
> + 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]));
> +
> + unmap_sysmem(hdr);
> +
> + /* Print image entries info */
> + for (i = 0; i < entry_count; ++i) {
> + const ulong e_addr = hdr_addr + entries_offset + i *
> entry_size;
> + const struct dt_table_entry *e;
> + const struct fdt_header *fdt;
> + u32 dt_offset, dt_size;
> + u32 j;
> +
> + e = map_sysmem(e_addr, sizeof(*e));
> + 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]));
> + }
> +
> + unmap_sysmem(e);
> +
> + /* Print FDT info for this entry */
> + fdt = map_sysmem(hdr_addr + dt_offset, sizeof(*fdt));
> + android_dt_print_fdt_info(fdt);
> + unmap_sysmem(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..08b810d461
> --- /dev/null
> +++ b/include/image-android-dt.h
> @@ -0,0 +1,21 @@
> +/*
> + * (C) Copyright 2018 Linaro Ltd.
> + * Sam Protsenko <semen.protsenko at linaro.org>
> + *
> + * SPDX-License-Identifier: GPL-2.0+
> + */
> +
> +#ifndef IMAGE_ANDROID_DT_H
> +#define IMAGE_ANDROID_DT_H
> +
> +#include <linux/types.h>
> +
> +bool android_dt_check_header(ulong hdr_addr);
> +bool android_dt_get_fdt_by_index(ulong hdr_addr, u32 index, ulong *addr,
> + u32 *size);
> +
> +#if !defined(CONFIG_SPL_BUILD)
> +void android_dt_print_contents(ulong hdr_addr);
> +#endif
> +
> +#endif /* IMAGE_ANDROID_DT_H */
> --
> 2.17.0
>
I haven't test this. Again, you probably want some maintainer to take a
look too.
Reviewed-by: Alex Deymo <deymo at google.com>
Regards,
Alex
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