/* SPDX-License-Identifier: GPL-2.0+ BSD-3-Clause */ /* * This provides a standard way of passing information between boot phases * (TPL -> SPL -> U-Boot proper.) * * It consists of a list of blobs of data, tagged with their owner / contents. * The list resides in memory and can be updated by SPL, U-Boot, etc. * * Design goals for bloblist: * * 1. Small and efficient structure. This avoids UUIDs or 16-byte name fields, * since a 32-bit tag provides enough space for all the tags we will even need. * If UUIDs are desired, they can be added inside a particular blob. * * 2. Avoids use of pointers, so the structure can be relocated in memory. The * data in each blob is inline, rather than using pointers. * * 3. Bloblist is designed to start small in TPL or SPL, when only a few things * are needed, like the memory size or whether console output should be enabled. * Then it can grow in U-Boot proper, e.g. to include space for ACPI tables. * * 4. The bloblist structure is simple enough that it can be implemented in a * small amount of C code. The API does not require use of strings or UUIDs, * which would add to code size. For Thumb-2 the code size needed in SPL is * approximately 940 bytes (e.g. for chromebook_bob). * * 5. Bloblist uses 16-byte alignment internally and is designed to start on a * 16-byte boundary. Its headers are multiples of 16 bytes. This makes it easier * to deal with data structures which need this level of alignment, such as ACPI * tables. For use in SPL and TPL the alignment can be relaxed, since it can be * relocated to an aligned address in U-Boot proper. * * 6. Bloblist is designed to be passed to Linux as reserved memory. While linux * doesn't understand the bloblist header, it can be passed the indivdual blobs. * For example, ACPI tables can reside in a blob and the address of those is * passed to Linux, without Linux ever being away of the existence of a * bloblist. Having all the blobs contiguous in memory simplifies the * reserved-memory space. * * 7. Bloblist tags are defined in the enum below. There is an area for * project-specific stuff (e.g. U-Boot, TF-A) and vendor-specific stuff, e.g. * something used only on a particular SoC. There is also a private area for * temporary, local use. * * 8. Bloblist includes a simple checksum, so that each boot phase can update * this and allow the next phase to check that all is well. While the bloblist * is small, this is quite cheap to calculate. When it grows (e.g. in U-Boot\ * proper), the CPU is likely running faster, so it is not prohibitive. Having * said that, U-Boot is often the last phase that uses bloblist, so calculating * the checksum there may not be necessary. * * 9. It would be possible to extend bloblist to support a non-contiguous * structure, e.g. by creating a blob type that points to the next bloblist. * This does not seem necessary for now. It adds complexity and code. We can * always just copy it. * * 10. Bloblist is designed for simple structures, those that can be defined by * a single C struct. More complex structures should be passed in a device tree. * There are some exceptions, chiefly the various binary structures that Intel * is fond of creating. But device tree provides a dictionary-type format which * is fairly efficient (for use in U-Boot proper and Linux at least), along with * a schema and a good set of tools. New formats should be designed around * device tree rather than creating new binary formats, unless they are needed * early in boot (where libfdt's 3KB of overhead is too large) and are trival * enough to be described by a C struct. * * Copyright 2018 Google, Inc * Written by Simon Glass */ #ifndef __BLOBLIST_H #define __BLOBLIST_H #include enum { BLOBLIST_VERSION = 0, BLOBLIST_MAGIC = 0xb00757a3, BLOBLIST_ALIGN = 16, }; /* Supported tags - add new ones to tag_name in bloblist.c */ enum bloblist_tag_t { BLOBLISTT_NONE = 0, /* * Standard area to allocate blobs used across firmware components, for * things that are very commonly used, particularly in multiple * projects. */ BLOBLISTT_AREA_FIRMWARE_TOP = 0x1, /* Standard area to allocate blobs used across firmware components */ BLOBLISTT_AREA_FIRMWARE = 0x100, /* * Advanced Configuration and Power Interface Global Non-Volatile * Sleeping table. This forms part of the ACPI tables passed to Linux. */ BLOBLISTT_ACPI_GNVS = 0x100, BLOBLISTT_INTEL_VBT = 0x101, /* Intel Video-BIOS table */ BLOBLISTT_TPM2_TCG_LOG = 0x102, /* TPM v2 log space */ BLOBLISTT_TCPA_LOG = 0x103, /* TPM log space */ BLOBLISTT_ACPI_TABLES = 0x104, /* ACPI tables for x86 */ BLOBLISTT_SMBIOS_TABLES = 0x105, /* SMBIOS tables for x86 */ BLOBLISTT_VBOOT_CTX = 0x106, /* Chromium OS verified boot context */ /* * Project-specific tags are permitted here. Projects can be open source * or not, but the format of the data must be fuily documented in an * open source project, including all fields, bits, etc. Naming should * be: BLOBLISTT__ */ BLOBLISTT_PROJECT_AREA = 0x8000, BLOBLISTT_U_BOOT_SPL_HANDOFF = 0x8000, /* Hand-off info from SPL */ BLOBLISTT_VBE = 0x8001, /* VBE per-phase state */ BLOBLISTT_U_BOOT_VIDEO = 0x8002, /* Video information from SPL */ /* * Vendor-specific tags are permitted here. Projects can be open source * or not, but the format of the data must be fuily documented in an * open source project, including all fields, bits, etc. Naming should * be BLOBLISTT__ */ BLOBLISTT_VENDOR_AREA = 0xc000, /* Tags after this are not allocated for now */ BLOBLISTT_EXPANSION = 0x10000, /* * Tags from here are on reserved for private use within a single * firmware binary (i.e. a single executable or phase of a project). * These tags can be passed between binaries within a local * implementation, but cannot be used in upstream code. Allocate a * tag in one of the areas above if you want that. * * This area may move in future. */ BLOBLISTT_PRIVATE_AREA = 0xffff0000, }; /** * struct bloblist_hdr - header for the bloblist * * This is stored at the start of the bloblist which is always on a 16-byte * boundary. Records follow this header. The bloblist normally stays in the * same place in memory as SPL and U-Boot execute, but it can be safely moved * around. * * None of the bloblist headers themselves contain pointers but it is possible * to put pointers inside a bloblist record if desired. This is not encouraged, * since it can make part of the bloblist inaccessible if the pointer is * no-longer valid. It is better to just store all the data inside a bloblist * record. * * Each bloblist record is aligned to a 16-byte boundary and follows immediately * from the last. * * @magic: BLOBLIST_MAGIC * @version: BLOBLIST_VERSION * @hdr_size: Size of this header, normally sizeof(struct bloblist_hdr). The * first bloblist_rec starts at this offset from the start of the header * @flags: Space for BLOBLISTF... flags (none yet) * @size: Total size of the bloblist (non-zero if valid) including this header. * The bloblist extends for this many bytes from the start of this header. * When adding new records, the bloblist can grow up to this size. * @alloced: Total size allocated so far for this bloblist. This starts out as * sizeof(bloblist_hdr) since we need at least that much space to store a * valid bloblist * @spare: Spare space (for future use) * @chksum: CRC32 for the entire bloblist allocated area. Since any of the * blobs can be altered after being created, this checksum is only valid * when the bloblist is finalised before jumping to the next stage of boot. * Note that chksum is last to make it easier to exclude it from the * checksum calculation. */ struct bloblist_hdr { u32 magic; u32 version; u32 hdr_size; u32 flags; u32 size; u32 alloced; u32 spare; u32 chksum; }; /** * struct bloblist_rec - record for the bloblist * * The bloblist contains a number of records each consisting of this record * structure followed by the data contained. Each records is 16-byte aligned. * * NOTE: Only exported for testing purposes. Do not use this struct. * * @tag: Tag indicating what the record contains * @hdr_size: Size of this header, normally sizeof(struct bloblist_rec). The * record's data starts at this offset from the start of the record * @size: Size of record in bytes, excluding the header size. This does not * need to be aligned (e.g. 3 is OK). * @spare: Spare space for other things */ struct bloblist_rec { u32 tag; u32 hdr_size; u32 size; u32 spare; }; /** * bloblist_check_magic() - return a bloblist if the magic matches * * @addr: Address to check * Return: pointer to bloblist, if the magic matches, else NULL */ static inline void *bloblist_check_magic(ulong addr) { u32 *ptr; if (!addr) return NULL; ptr = map_sysmem(addr, 0); if (*ptr != BLOBLIST_MAGIC) return NULL; return ptr; } /** * bloblist_find() - Find a blob * * Searches the bloblist and returns the blob with the matching tag * * @tag: Tag to search for (enum bloblist_tag_t) * @size: Expected size of the blob, or 0 for any size * Return: pointer to blob if found, or NULL if not found, or a blob was found * but it is the wrong size */ void *bloblist_find(uint tag, int size); /** * bloblist_add() - Add a new blob * * Add a new blob to the bloblist * * This should only be called if you konw there is no existing blob for a * particular tag. It is typically safe to call in the first phase of U-Boot * (e.g. TPL or SPL). After that, bloblist_ensure() should be used instead. * * @tag: Tag to add (enum bloblist_tag_t) * @size: Size of the blob * @align: Alignment of the blob (in bytes), 0 for default * Return: pointer to the newly added block, or NULL if there is not enough * space for the blob */ void *bloblist_add(uint tag, int size, int align); /** * bloblist_ensure_size() - Find or add a blob * * Find an existing blob, or add a new one if not found * * @tag: Tag to add (enum bloblist_tag_t) * @size: Size of the blob * @blobp: Returns a pointer to blob on success * @align: Alignment of the blob (in bytes), 0 for default * Return: 0 if OK, -ENOSPC if it is missing and could not be added due to lack * of space, or -ESPIPE it exists but has the wrong size */ int bloblist_ensure_size(uint tag, int size, int align, void **blobp); /** * bloblist_ensure() - Find or add a blob * * Find an existing blob, or add a new one if not found * * @tag: Tag to add (enum bloblist_tag_t) * @size: Size of the blob * Return: pointer to blob, or NULL if it is missing and could not be added due * to lack of space, or it exists but has the wrong size */ void *bloblist_ensure(uint tag, int size); /** * bloblist_ensure_size_ret() - Find or add a blob * * Find an existing blob, or add a new one if not found * * @tag: Tag to add (enum bloblist_tag_t) * @sizep: Size of the blob to create; returns size of actual blob * @blobp: Returns a pointer to blob on success * Return: 0 if OK, -ENOSPC if it is missing and could not be added due to lack * of space */ int bloblist_ensure_size_ret(uint tag, int *sizep, void **blobp); /** * bloblist_resize() - resize a blob * * Any blobs above this one are relocated up or down. The resized blob remains * in the same place. * * @tag: Tag to add (enum bloblist_tag_t) * @new_size: New size of the blob (>0 to expand, <0 to contract) * Return: 0 if OK, -ENOSPC if the bloblist does not have enough space, -ENOENT * if the tag is not found */ int bloblist_resize(uint tag, int new_size); /** * bloblist_new() - Create a new, empty bloblist of a given size * * @addr: Address of bloblist * @size: Initial size for bloblist * @flags: Flags to use for bloblist * Return: 0 if OK, -EFAULT if addr is not aligned correctly, -ENOSPC is the * area is not large enough */ int bloblist_new(ulong addr, uint size, uint flags); /** * bloblist_check() - Check if a bloblist exists * * @addr: Address of bloblist * @size: Expected size of blobsize, or 0 to detect the size * Return: 0 if OK, -ENOENT if the magic number doesn't match (indicating that * there problem is no bloblist at the given address), -EPROTONOSUPPORT * if the version does not match, -EIO if the checksum does not match, * -EFBIG if the expected size does not match the detected size, -ENOSPC * if the size is not large enough to hold the headers */ int bloblist_check(ulong addr, uint size); /** * bloblist_finish() - Set up the bloblist for the next U-Boot part * * This sets the correct checksum for the bloblist. This ensures that the * bloblist will be detected correctly by the next phase of U-Boot. * * Return: 0 */ int bloblist_finish(void); /** * bloblist_get_stats() - Get information about the bloblist * * This returns useful information about the bloblist * * @basep: Returns base address of bloblist * @sizep: Returns the number of bytes used in the bloblist * @allocedp: Returns the total space allocated to the bloblist */ void bloblist_get_stats(ulong *basep, ulong *sizep, ulong *allocedp); /** * bloblist_get_base() - Get the base address of the bloblist * * Return: base address of bloblist */ ulong bloblist_get_base(void); /** * bloblist_get_size() - Get the size of the bloblist * * Return: the size in bytes */ ulong bloblist_get_size(void); /** * bloblist_show_stats() - Show information about the bloblist * * This shows useful information about the bloblist on the console */ void bloblist_show_stats(void); /** * bloblist_show_list() - Show a list of blobs in the bloblist * * This shows a list of blobs, showing their address, size and tag. */ void bloblist_show_list(void); /** * bloblist_tag_name() - Get the name for a tag * * @tag: Tag to check * Return: name of tag, or "invalid" if an invalid tag is provided */ const char *bloblist_tag_name(enum bloblist_tag_t tag); /** * bloblist_reloc() - Relocate the bloblist and optionally resize it * * @to: Pointer to new bloblist location (must not overlap old location) * @to_size: New size for bloblist (must be larger than from_size) * @from: Pointer to bloblist to relocate * @from_size: Size of bloblist to relocate */ void bloblist_reloc(void *to, uint to_size, void *from, uint from_size); /** * bloblist_init() - Init the bloblist system with a single bloblist * * This locates and sets up the blocklist for use. * * If CONFIG_BLOBLIST_FIXED is selected, it uses CONFIG_BLOBLIST_ADDR and * CONFIG_BLOBLIST_SIZE to set up a bloblist for use by U-Boot. * * If CONFIG_BLOBLIST_ALLOC is selected, it allocates memory for a bloblist of * size CONFIG_BLOBLIST_SIZE. * * If CONFIG_BLOBLIST_PASSAGE is selected, it uses the bloblist in the incoming * standard passage. The size is detected automatically so CONFIG_BLOBLIST_SIZE * can be 0. * * Return: 0 if OK, -ve on error */ int bloblist_init(void); #endif /* __BLOBLIST_H */