u-boot/include/bloblist.h

421 lines
15 KiB
C
Raw Normal View History

/* 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 <sjg@chromium.org>
*/
#ifndef __BLOBLIST_H
#define __BLOBLIST_H
#include <mapmem.h>
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_<project>_<purpose_here>
*/
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_<vendor>_<purpose_here>
*/
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 */