diff options
Diffstat (limited to 'ldso/ldso/xtensa/dl-startup.h')
-rw-r--r-- | ldso/ldso/xtensa/dl-startup.h | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/ldso/ldso/xtensa/dl-startup.h b/ldso/ldso/xtensa/dl-startup.h new file mode 100644 index 000000000..2fd012846 --- /dev/null +++ b/ldso/ldso/xtensa/dl-startup.h @@ -0,0 +1,106 @@ +/* vi: set sw=4 ts=4: */ +/* + * Xtensa ELF code used by dl-startup.c. + * + * Copyright (C) 2007 Tensilica Inc. + * + * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball. + * Parts taken from glibc/sysdeps/xtensa/dl-machine.h. + */ + +__asm__ ( + " .text\n" + " .align 4\n" + " .global _start\n" + " .type _start, @function\n" + "_start:\n" + " # Compute load offset in a2: the GOT has not yet been relocated\n" + " # but the entries for local symbols contain the relative offsets\n" + " # and we can explicitly add the load offset in this code.\n" + " _call0 0f\n" + " .align 4\n" + "0: movi a3, _start+3\n" + " sub a2, a0, a3\n" + " # Make sure a0 is cleared to mark the top of stack.\n" + " movi a0, 0\n" + " # user_entry_point = _dl_start(pointer to argument block)\n" + " movi a4, _dl_start\n" + " mov a6, sp\n" + " add a4, a4, a2\n" + " callx4 a4\n" + " # Save user_entry_point so we can jump to it.\n" + " mov a3, a6\n" + " l32i a7, sp, 0 # load argc\n" + " # Load _dl_skip_args into a4.\n" + " movi a4, _dl_skip_args\n" + " l32i a4, a4, 0\n" + " bnez a4, .Lfixup_stack\n" + ".Lfixup_stack_ret:\n" + " # Pass finalizer (_dl_fini) in a2 to the user entry point.\n" + " movi a2, _dl_fini\n" + " # Jump to user's entry point (_start).\n" + " jx a3\n" + ".Lfixup_stack:\n" + " # argc -= _dl_skip_args (with argc @ sp+0)\n" + " sub a7, a7, a4\n" + " s32i a7, sp, 0\n" + " # Shift everything by _dl_skip_args.\n" + " addi a5, sp, 4 # a5 = destination ptr = argv\n" + " add a4, a5, a4 # a4 = source ptr = argv + _dl_skip_args\n" + " # Shift argv.\n" + "1: l32i a6, a4, 0\n" + " addi a4, a4, 4\n" + " s32i a6, a5, 0\n" + " addi a5, a5, 4\n" + " bnez a6, 1b\n" + " # Shift envp.\n" + "2: l32i a6, a4, 0\n" + " addi a4, a4, 4\n" + " s32i a6, a5, 0\n" + " addi a5, a5, 4\n" + " bnez a6, 2b\n" + " # Shift auxiliary table.\n" + "3: l32i a6, a4, 0\n" + " l32i a8, a4, 4\n" + " addi a4, a4, 8\n" + " s32i a6, a5, 0\n" + " s32i a8, a5, 4\n" + " addi a5, a5, 8\n" + " bnez a6, 3b\n" + " j .Lfixup_stack_ret"); + +/* Get a pointer to the argv value. */ +#define GET_ARGV(ARGVP, ARGS) ARGVP = (((unsigned long *) ARGS) + 1) + +/* Function calls are not safe until the GOT relocations have been done. */ +#define NO_FUNCS_BEFORE_BOOTSTRAP + +#define PERFORM_BOOTSTRAP_GOT(tpnt) \ +do { \ + xtensa_got_location *got_loc; \ + unsigned long l_addr = tpnt->loadaddr; \ + Elf32_Word relative_count; \ + unsigned long rel_addr; \ + int x; \ +\ + got_loc = (xtensa_got_location *) \ + (tpnt->dynamic_info[DT_XTENSA (GOT_LOC_OFF)] + l_addr); \ +\ + for (x = 0; x < tpnt->dynamic_info[DT_XTENSA (GOT_LOC_SZ)]; x++) { \ + Elf32_Addr got_start, got_end; \ + got_start = got_loc[x].offset & ~(PAGE_SIZE - 1); \ + got_end = ((got_loc[x].offset + got_loc[x].length + PAGE_SIZE - 1) \ + & ~(PAGE_SIZE - 1)); \ + _dl_mprotect ((void *)(got_start + l_addr), got_end - got_start, \ + PROT_READ | PROT_WRITE | PROT_EXEC); \ + } \ +\ + /* The following is a stripped down version of the code following \ + the invocation of PERFORM_BOOTSTRAP_GOT in dl-startup.c. That \ + code is skipped when PERFORM_BOOTSTRAP_GOT is defined, so it has \ + to be done here instead. */ \ + relative_count = tpnt->dynamic_info[DT_RELCONT_IDX]; \ + rel_addr = tpnt->dynamic_info[DT_RELOC_TABLE_ADDR]; \ + if (rel_addr) \ + elf_machine_relative(load_addr, rel_addr, relative_count); \ +} while (0) |