The C6X port

This adds support for the TI C6X family of processors.

Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Aurelien Jacquiot <a-jacquiot@ti.com>
Signed-off-by: Bernd Schmidt <bernds@codesourcery.com>

1 files changed, 123 insertions, 0 deletions

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 <elf.h>
+
+/* 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 */