From 46d6a24872b7fa2717f8f71b5e0598a14d38e1f6 Mon Sep 17 00:00:00 2001 From: Aurelien Jacquiot Date: Wed, 23 Feb 2011 13:04:59 +0100 Subject: The C6X port This adds support for the TI C6X family of processors. Signed-off-by: Mark Salter Signed-off-by: Aurelien Jacquiot Signed-off-by: Bernd Schmidt --- libc/sysdeps/linux/c6x/bits/elf-dsbt.h | 123 +++++++++++++++++++++++++++++++++ 1 file changed, 123 insertions(+) create mode 100644 libc/sysdeps/linux/c6x/bits/elf-dsbt.h (limited to 'libc/sysdeps/linux/c6x/bits/elf-dsbt.h') diff --git a/libc/sysdeps/linux/c6x/bits/elf-dsbt.h b/libc/sysdeps/linux/c6x/bits/elf-dsbt.h new file mode 100644 index 000000000..ff8b24bd7 --- /dev/null +++ b/libc/sysdeps/linux/c6x/bits/elf-dsbt.h @@ -0,0 +1,123 @@ +/* Copyright (C) 2010 Texas Instruments Incorporated + +Borrowed heavily from frv arch: +Copyright 2003, 2004 Free Software Foundation, Inc. +This file is part of the GNU C Library. + +The GNU C Library is free software; you can redistribute it and/or +modify it under the terms of the GNU Lesser General Public License as +published by the Free Software Foundation; either version 2.1 of the +License, or (at your option) any later version. + +In addition to the permissions in the GNU Lesser General Public +License, the Free Software Foundation gives you unlimited +permission to link the compiled version of this file with other +programs, and to distribute those programs without any restriction +coming from the use of this file. (The GNU Lesser General Public +License restrictions do apply in other respects; for example, they +cover modification of the file, and distribution when not linked +into another program.) + +The GNU C Library 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 +Library General Public License for more details. + +You should have received a copy of the GNU Lesser General Public +License along with the GNU C Library; see the file COPYING.LIB. If +not, write to the Free Software Foundation, Inc., 675 Mass Ave, +Cambridge, MA 02139, USA. */ + +#ifndef _BITS_ELF_DSBT_H +#define _BITS_ELF_DSBT_H + +/* These data structures are described in the DSBT ABI. + The kernel passes a process a memory map of logical + load segments. For PIC code to work, all code segments + must be combined into a single mapping while maintaining + their relationship to one another. The same is true for + RW data segments. + + Furthermore, + segment there is an elf32_dsbt_loadseg entry. A pointer to an + elf32_dsbt_loadmap is passed in GR8 at start-up, and a pointer to + an additional such map is passed in GR9 for the interpreter, when + there is one. */ + +#include + +/* This data structure represents a PT_LOAD segment. */ +struct elf32_dsbt_loadseg +{ + /* Core address to which the segment is mapped. */ + Elf32_Addr addr; + /* VMA recorded in the program header. */ + Elf32_Addr p_vaddr; + /* Size of this segment in memory. */ + Elf32_Word p_memsz; +}; + +struct elf32_dsbt_loadmap { + /* Protocol version number, must be zero. */ + Elf32_Word version; + + /* Pointer to DSBT */ + unsigned *dsbt_table; + unsigned dsbt_size; + unsigned dsbt_index; + + /* number of segments */ + Elf32_Word nsegs; + + /* The actual memory map. */ + struct elf32_dsbt_loadseg segs[0]; +}; + +struct elf32_dsbt_loadaddr { + struct elf32_dsbt_loadmap *map; +}; + + +/* Map a pointer's VMA to its corresponding address according to the + load map. */ +static __always_inline void * +__reloc_pointer (void *p, + const struct elf32_dsbt_loadmap *map) +{ + int c; + +#if 0 + if (map->version != 0) + /* Crash. */ + ((void(*)())0)(); +#endif + + /* No special provision is made for NULL. We don't want NULL + addresses to go through relocation, so they shouldn't be in + .rofixup sections, and, if they're present in dynamic + relocations, they shall be mapped to the NULL address without + undergoing relocations. */ + + for (c = 0; c < map->nsegs; c++) + { + unsigned long offset = p - (void*)map->segs[c].p_vaddr; + /* We only check for one-past-the-end for the second segment, + assumed to be the data segment, because other cases are + ambiguous in the absence of padding between segments, and + rofixup already serves as padding between text and data. + Unfortunately, unless we special-case the second segment, + we fail to relocate the _end symbol. */ + if (offset < map->segs[c].p_memsz + || (offset == map->segs[c].p_memsz && c == 1)) + return (char*)map->segs[c].addr + offset; + } + + /* We might want to crash instead. */ + return (void*)-1; +} + +# define __RELOC_POINTER(ptr, loadaddr) \ + (__reloc_pointer ((void*)(ptr), \ + (loadaddr).map)) + +#endif /* _BITS_ELF_DSBT_H */ -- cgit v1.2.3