| /* |
| * This file is part of the coreboot project. |
| * |
| * Copyright (C) 2012 ChromeOS Authors |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; version 2 of the License. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| #include <stdint.h> |
| #include <string.h> |
| #include <console/console.h> |
| #include <rmodule.h> |
| |
| /* Change this define to get more verbose debugging for module loading. */ |
| #define PK_ADJ_LEVEL BIOS_NEVER |
| |
| #if CONFIG_ARCH_X86 |
| /* |
| * On X86, the only relocations currently allowed are R_386_RELATIVE which |
| * have '0' for the symbol info in the relocation metadata (in r_info). |
| * The reason is that the module is fully linked and just has the relocations' |
| * locations. |
| */ |
| typedef struct { |
| u32 r_offset; |
| u32 r_info; |
| } Elf32_Rel; |
| |
| #define R_386_RELATIVE 8 |
| |
| #define RELOCTION_ENTRY_SIZE sizeof(Elf32_Rel) |
| static inline int rmodule_reloc_offset(const void *reloc) |
| { |
| const Elf32_Rel *rel = reloc; |
| return rel->r_offset; |
| } |
| |
| static inline int rmodule_reloc_valid(const void *reloc) |
| { |
| const Elf32_Rel *rel = reloc; |
| return (rel->r_info == R_386_RELATIVE); |
| } |
| |
| static inline void *remodule_next_reloc(const void *reloc) |
| { |
| const Elf32_Rel *rel = reloc; |
| rel++; |
| return (void *)rel; |
| } |
| |
| #else |
| #error Arch needs to add relocation information support for RMODULE |
| #endif |
| |
| static inline int rmodule_is_loaded(const struct rmodule *module) |
| { |
| return module->location != NULL; |
| } |
| |
| /* Calculate a loaded program address based on the blob address. */ |
| static inline void *rmodule_load_addr(const struct rmodule *module, |
| u32 blob_addr) |
| { |
| char *loc = module->location; |
| return &loc[blob_addr - module->header->module_link_start_address]; |
| } |
| |
| /* Initialize a rmodule structure based on raw data. */ |
| int rmodule_parse(void *ptr, struct rmodule *module) |
| { |
| char *base; |
| struct rmodule_header *rhdr; |
| |
| base = ptr; |
| rhdr = ptr; |
| |
| if (rhdr == NULL) |
| return -1; |
| |
| /* Sanity check the raw data. */ |
| if (rhdr->magic != RMODULE_MAGIC) |
| return -1; |
| if (rhdr->version != RMODULE_VERSION_1) |
| return -1; |
| |
| /* Indicate the module hasn't been loaded yet. */ |
| module->location = NULL; |
| |
| /* The rmodule only needs a reference to the reloc_header. */ |
| module->header = rhdr; |
| |
| /* The payload lives after the header. */ |
| module->payload = &base[rhdr->payload_begin_offset]; |
| module->payload_size = rhdr->payload_end_offset - |
| rhdr->payload_begin_offset; |
| module->relocations = &base[rhdr->relocations_begin_offset]; |
| |
| return 0; |
| } |
| |
| int rmodule_memory_size(const struct rmodule *module) |
| { |
| return module->header->module_program_size; |
| } |
| |
| void *rmodule_parameters(const struct rmodule *module) |
| { |
| if (!rmodule_is_loaded(module)) |
| return NULL; |
| |
| /* Indicate if there are no parameters. */ |
| if (module->header->parameters_begin == module->header->parameters_end) |
| return NULL; |
| |
| return rmodule_load_addr(module, module->header->parameters_begin); |
| } |
| |
| int rmodule_entry_offset(const struct rmodule *module) |
| { |
| return module->header->module_entry_point - |
| module->header->module_link_start_address; |
| } |
| |
| void *rmodule_entry(const struct rmodule *module) |
| { |
| if (!rmodule_is_loaded(module)) |
| return NULL; |
| |
| return rmodule_load_addr(module, module->header->module_entry_point); |
| } |
| |
| static void rmodule_clear_bss(struct rmodule *module) |
| { |
| char *begin; |
| int size; |
| |
| begin = rmodule_load_addr(module, module->header->bss_begin); |
| size = module->header->bss_end - module->header->bss_begin; |
| memset(begin, 0, size); |
| } |
| |
| static inline int rmodule_number_relocations(const struct rmodule *module) |
| { |
| int r; |
| |
| r = module->header->relocations_end_offset; |
| r -= module->header->relocations_begin_offset; |
| r /= RELOCTION_ENTRY_SIZE; |
| return r; |
| } |
| |
| static void rmodule_copy_payload(const struct rmodule *module) |
| { |
| printk(BIOS_DEBUG, "Loading module at %p with entry %p. " |
| "filesize: 0x%x memsize: 0x%x\n", |
| module->location, rmodule_entry(module), |
| module->payload_size, rmodule_memory_size(module)); |
| memcpy(module->location, module->payload, module->payload_size); |
| } |
| |
| static inline u32 *rmodule_adjustment_location(const struct rmodule *module, |
| const void *reloc) |
| { |
| int reloc_offset; |
| |
| /* Don't relocate header field entries -- only program relocations. */ |
| reloc_offset = rmodule_reloc_offset(reloc); |
| if (reloc_offset < module->header->module_link_start_address) |
| return NULL; |
| |
| return rmodule_load_addr(module, reloc_offset); |
| } |
| |
| static int rmodule_relocate(const struct rmodule *module) |
| { |
| int num_relocations; |
| const void *reloc; |
| u32 adjustment; |
| |
| /* Each relocation needs to be adjusted relative to the beginning of |
| * the loaded program. */ |
| adjustment = (u32)rmodule_load_addr(module, 0); |
| |
| reloc = module->relocations; |
| num_relocations = rmodule_number_relocations(module); |
| |
| printk(BIOS_DEBUG, "Processing %d relocs with adjust value of 0x%08x\n", |
| num_relocations, adjustment); |
| |
| while (num_relocations > 0) { |
| u32 *adjust_loc; |
| |
| if (!rmodule_reloc_valid(reloc)) |
| return -1; |
| |
| /* If the adjustment location is non-NULL adjust it. */ |
| adjust_loc = rmodule_adjustment_location(module, reloc); |
| if (adjust_loc != NULL) { |
| printk(PK_ADJ_LEVEL, "Adjusting %p: 0x%08x -> 0x%08x\n", |
| adjust_loc, *adjust_loc, |
| *adjust_loc + adjustment); |
| *adjust_loc += adjustment; |
| } |
| |
| reloc = remodule_next_reloc(reloc); |
| num_relocations--; |
| } |
| |
| return 0; |
| } |
| |
| int rmodule_load_alignment(const struct rmodule *module) |
| { |
| /* The load alignment is the start of the program's linked address. |
| * The base address where the program is loaded needs to be a multiple |
| * of the program's starting link address. That way all data alignment |
| * in the program is presered. */ |
| return module->header->module_link_start_address; |
| } |
| |
| int rmodule_load(void *base, struct rmodule *module) |
| { |
| /* |
| * In order to load the module at a given address, the following steps |
| * take place: |
| * 1. Copy payload to base address. |
| * 2. Clear the bss segment. |
| * 3. Adjust relocations within the module to new base address. |
| */ |
| module->location = base; |
| rmodule_copy_payload(module); |
| rmodule_clear_bss(module); |
| return rmodule_relocate(module); |
| } |
| |