elf_loader.h

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/*
 * Copyright (c) 2014, Mentor Graphics Corporation
 * All rights reserved.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */
 
#ifndef ELF_LOADER_H_
#define ELF_LOADER_H_
 
#include <openamp/remoteproc.h>
#include <openamp/remoteproc_loader.h>
 
#if defined __cplusplus
extern "C" {
#endif
 
/* ELF32 base types - 32-bit. */
typedef uint32_t Elf32_Addr;
typedef uint16_t Elf32_Half;
typedef uint32_t Elf32_Off;
typedef int32_t Elf32_Sword;
typedef uint32_t Elf32_Word;
 
/* ELF64 base types - 64-bit. */
typedef uint64_t Elf64_Addr;
typedef uint16_t Elf64_Half;
typedef uint64_t Elf64_Off;
typedef int32_t Elf64_Sword;
typedef uint32_t Elf64_Word;
typedef uint64_t Elf64_Xword;
typedef int64_t Elf64_Sxword;
 
/* Size of ELF identifier field in the ELF file header. */
#define     EI_NIDENT       16
 
/* ELF32 file header */
typedef struct {
        unsigned char e_ident[EI_NIDENT];
        Elf32_Half e_type;
        Elf32_Half e_machine;
        Elf32_Word e_version;
        Elf32_Addr e_entry;
        Elf32_Off e_phoff;
        Elf32_Off e_shoff;
        Elf32_Word e_flags;
        Elf32_Half e_ehsize;
        Elf32_Half e_phentsize;
        Elf32_Half e_phnum;
        Elf32_Half e_shentsize;
        Elf32_Half e_shnum;
        Elf32_Half e_shstrndx;
} Elf32_Ehdr;
 
/* ELF64 file header */
typedef struct {
        unsigned char e_ident[EI_NIDENT];
        Elf64_Half e_type;
        Elf64_Half e_machine;
        Elf64_Word e_version;
        Elf64_Addr e_entry;
        Elf64_Off e_phoff;
        Elf64_Off e_shoff;
        Elf64_Word e_flags;
        Elf64_Half e_ehsize;
        Elf64_Half e_phentsize;
        Elf64_Half e_phnum;
        Elf64_Half e_shentsize;
        Elf64_Half e_shnum;
        Elf64_Half e_shstrndx;
} Elf64_Ehdr;
 
/* e_ident */
#define     ET_NONE         0
#define     ET_REL          1   /* Re-locatable file         */
#define     ET_EXEC         2   /* Executable file           */
#define     ET_DYN          3   /* Shared object file        */
#define     ET_CORE         4   /* Core file                 */
#define     ET_LOOS         0xfe00      /* Operating system-specific */
#define     ET_HIOS         0xfeff      /* Operating system-specific */
#define     ET_LOPROC       0xff00      /* remote_proc-specific        */
#define     ET_HIPROC       0xffff      /* remote_proc-specific        */
 
/* e_machine */
#define     EM_ARM          40  /* ARM/Thumb Architecture    */
 
/* e_version */
#define     EV_CURRENT      1   /* Current version           */
 
/* e_ident[] Identification Indexes */
#define     EI_MAG0         0   /* File identification       */
#define     EI_MAG1         1   /* File identification       */
#define     EI_MAG2         2   /* File identification       */
#define     EI_MAG3         3   /* File identification       */
#define     EI_CLASS        4   /* File class                */
#define     EI_DATA         5   /* Data encoding             */
#define     EI_VERSION      6   /* File version              */
#define     EI_OSABI        7   /* Operating system/ABI identification */
#define     EI_ABIVERSION   8   /* ABI version               */
#define     EI_PAD          9   /* Start of padding bytes    */
#define     EI_NIDENT       16  /* Size of e_ident[]         */
 
/*
 * EI_MAG0 to EI_MAG3 - A file's first 4 bytes hold amagic number, identifying
 * the file as an ELF object file
 */
#define     ELFMAG0         0x7f /* e_ident[EI_MAG0]          */
#define     ELFMAG1         'E' /* e_ident[EI_MAG1]          */
#define     ELFMAG2         'L' /* e_ident[EI_MAG2]          */
#define     ELFMAG3         'F' /* e_ident[EI_MAG3]          */
#define     ELFMAG          "\177ELF"
#define     SELFMAG         4
 
/*
 * EI_CLASS - The next byte, e_ident[EI_CLASS], identifies the file's class, or
 * capacity.
 */
#define     ELFCLASSNONE    0   /* Invalid class             */
#define     ELFCLASS32      1   /* 32-bit objects            */
#define     ELFCLASS64      2   /* 64-bit objects            */
 
/*
 * EI_DATA - Byte e_ident[EI_DATA] specifies the data encoding of the
 * remote_proc-specific data in the object file. The following encodings are
 * currently defined.
 */
#define     ELFDATANONE     0   /* Invalid data encoding     */
#define     ELFDATA2LSB     1   /* See Data encodings, below */
#define     ELFDATA2MSB     2   /* See Data encodings, below */
 
/* EI_OSABI - We do not define an OS specific ABI */
#define     ELFOSABI_NONE   0
 
/* ELF32 program header */
typedef struct elf32_phdr {
        Elf32_Word p_type;
        Elf32_Off p_offset;
        Elf32_Addr p_vaddr;
        Elf32_Addr p_paddr;
        Elf32_Word p_filesz;
        Elf32_Word p_memsz;
        Elf32_Word p_flags;
        Elf32_Word p_align;
} Elf32_Phdr;
 
/* ELF64 program header */
typedef struct elf64_phdr {
        Elf64_Word p_type;
        Elf64_Word p_flags;
        Elf64_Off p_offset;
        Elf64_Addr p_vaddr;
        Elf64_Addr p_paddr;
        Elf64_Xword p_filesz;
        Elf64_Xword p_memsz;
        Elf64_Xword p_align;
} Elf64_Phdr;
 
/* segment types */
#define PT_NULL    0
#define PT_LOAD    1
#define PT_DYNAMIC 2
#define PT_INTERP  3
#define PT_NOTE    4
#define PT_SHLIB   5
#define PT_PHDR    6
#define PT_TLS     7               /* Thread local storage segment */
#define PT_LOOS    0x60000000      /* OS-specific */
#define PT_HIOS    0x6fffffff      /* OS-specific */
#define PT_LOPROC  0x70000000
#define PT_HIPROC  0x7fffffff
 
/* ELF32 section header. */
typedef struct {
        Elf32_Word sh_name;
        Elf32_Word sh_type;
        Elf32_Word sh_flags;
        Elf32_Addr sh_addr;
        Elf32_Off sh_offset;
        Elf32_Word sh_size;
        Elf32_Word sh_link;
        Elf32_Word sh_info;
        Elf32_Word sh_addralign;
        Elf32_Word sh_entsize;
} Elf32_Shdr;
 
/* ELF64 section header. */
typedef struct {
        Elf64_Word sh_name;
        Elf64_Word sh_type;
        Elf64_Xword sh_flags;
        Elf64_Addr sh_addr;
        Elf64_Off sh_offset;
        Elf64_Xword sh_size;
        Elf64_Word sh_link;
        Elf64_Word sh_info;
        Elf64_Xword sh_addralign;
        Elf64_Xword sh_entsize;
} Elf64_Shdr;
 
/* sh_type */
#define     SHT_NULL                0
#define     SHT_PROGBITS            1
#define     SHT_SYMTAB              2
#define     SHT_STRTAB              3
#define     SHT_RELA                4
#define     SHT_HASH                5
#define     SHT_DYNAMIC             6
#define     SHT_NOTE                7
#define     SHT_NOBITS              8
#define     SHT_REL                 9
#define     SHT_SHLIB               10
#define     SHT_DYNSYM              11
#define     SHT_INIT_ARRAY          14
#define     SHT_FINI_ARRAY          15
#define     SHT_PREINIT_ARRAY       16
#define     SHT_GROUP               17
#define     SHT_SYMTAB_SHNDX        18
#define     SHT_LOOS                0x60000000
#define     SHT_HIOS                0x6fffffff
#define     SHT_LOPROC              0x70000000
#define     SHT_HIPROC              0x7fffffff
#define     SHT_LOUSER              0x80000000
#define     SHT_HIUSER              0xffffffff
 
/* sh_flags */
#define     SHF_WRITE       0x1
#define     SHF_ALLOC       0x2
#define     SHF_EXECINSTR   0x4
#define     SHF_MASKPROC    0xf0000000
 
/* Relocation entry (without addend) */
typedef struct {
        Elf32_Addr r_offset;
        Elf32_Word r_info;
} Elf32_Rel;
 
typedef struct {
        Elf64_Addr r_offset;
        Elf64_Xword r_info;
} Elf64_Rel;
 
/* Relocation entry with addend */
typedef struct {
        Elf32_Addr r_offset;
        Elf32_Word r_info;
        Elf32_Sword r_addend;
} Elf32_Rela;
 
typedef struct elf64_rela {
        Elf64_Addr r_offset;
        Elf64_Xword r_info;
        Elf64_Sxword r_addend;
} Elf64_Rela;
 
/* Macros to extract information from 'r_info' field of relocation entries */
#define ELF32_R_SYM(i)  ((i) >> 8)
#define ELF32_R_TYPE(i) ((unsigned char)(i))
#define ELF64_R_SYM(i)  ((i) >> 32)
#define ELF64_R_TYPE(i) ((i) & 0xffffffff)
 
/* Symbol table entry */
typedef struct {
        Elf32_Word st_name;
        Elf32_Addr st_value;
        Elf32_Word st_size;
        unsigned char st_info;
        unsigned char st_other;
        Elf32_Half st_shndx;
} Elf32_Sym;
 
typedef struct elf64_sym {
        Elf64_Word st_name;
        unsigned char st_info;
        unsigned char st_other;
        Elf64_Half st_shndx;
        Elf64_Addr st_value;
        Elf64_Xword st_size;
} Elf64_Sym;
 
/* ARM specific dynamic relocation codes */
#define     R_ARM_GLOB_DAT      21      /* 0x15 */
#define     R_ARM_JUMP_SLOT     22      /* 0x16 */
#define     R_ARM_RELATIVE      23      /* 0x17 */
#define     R_ARM_ABS32         2       /* 0x02 */
 
/* ELF decoding information */
struct elf32_info {
        Elf32_Ehdr ehdr;
        int load_state;
        Elf32_Phdr *phdrs;
        Elf32_Shdr *shdrs;
        void *shstrtab;
};
 
struct elf64_info {
        Elf64_Ehdr ehdr;
        int load_state;
        Elf64_Phdr *phdrs;
        Elf64_Shdr *shdrs;
        void *shstrtab;
};
 
#define ELF_STATE_INIT              0x0L
#define ELF_STATE_WAIT_FOR_PHDRS    0x100L
#define ELF_STATE_WAIT_FOR_SHDRS    0x200L
#define ELF_STATE_WAIT_FOR_SHSTRTAB 0x400L
#define ELF_STATE_HDRS_COMPLETE     0x800L
#define ELF_STATE_MASK              0xFF00L
#define ELF_NEXT_SEGMENT_MASK       0x00FFL
 
extern const struct loader_ops elf_ops;
 
int elf_identify(const void *img_data, size_t len);
 
int elf_load_header(const void *img_data, size_t offset, size_t len,
                    void **img_info, int last_load_state,
                    size_t *noffset, size_t *nlen);
 
int elf_load(struct remoteproc *rproc, const void *img_data,
             size_t offset, size_t len,
             void **img_info, int last_load_state,
             metal_phys_addr_t *da,
             size_t *noffset, size_t *nlen,
             unsigned char *padding, size_t *nmemsize);
 
void elf_release(void *img_info);
 
metal_phys_addr_t elf_get_entry(void *img_info);
 
int elf_locate_rsc_table(void *img_info, metal_phys_addr_t *da,
                         size_t *offset, size_t *size);
 
#if defined __cplusplus
}
#endif
 
#endif /* ELF_LOADER_H_ */