Introduce generic link section.h symbol files

We create a separate header file for link symbols defined by the link
scripts. It is helpful to have these all in one place and try to
make them common across architectures. Since Linux already has a similar
file, we bring this in even though many of the symbols there are not
relevant to us.

Each architecture has its own asm/sections.h where symbols specifc to
that architecture can be added. For now everything except AVR32 just
includes the generic header.

One change is needed in arch/avr32/lib/board.c to make this conversion
work.

Reviewed-by: Tom Rini <trini@ti.com> (version 5)
Signed-off-by: Simon Glass <sjg@chromium.org>

1 files changed, 117 insertions, 0 deletions

diff --git a/include/asm-generic/sections.h b/include/asm-generic/sections.h
new file mode 100644
index 0000000000..cca1edb0c7
--- /dev/null
+++ b/include/asm-generic/sections.h
@@ -0,0 +1,117 @@
+/*
+ * Copyright (c) 2011 The Chromium OS 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; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+/* Taken from Linux kernel, commit f56c3196 */
+
+#ifndef _ASM_GENERIC_SECTIONS_H_
+#define _ASM_GENERIC_SECTIONS_H_
+
+/* References to section boundaries */
+
+extern char _text[], _stext[], _etext[];
+extern char _data[], _sdata[], _edata[];
+extern char __bss_start[], __bss_stop[];
+extern char __init_begin[], __init_end[];
+extern char _sinittext[], _einittext[];
+extern char _end[];
+extern char __per_cpu_load[], __per_cpu_start[], __per_cpu_end[];
+extern char __kprobes_text_start[], __kprobes_text_end[];
+extern char __entry_text_start[], __entry_text_end[];
+extern char __initdata_begin[], __initdata_end[];
+extern char __start_rodata[], __end_rodata[];
+
+/* Start and end of .ctors section - used for constructor calls. */
+extern char __ctors_start[], __ctors_end[];
+
+/* function descriptor handling (if any).  Override
+ * in asm/sections.h */
+#ifndef dereference_function_descriptor
+#define dereference_function_descriptor(p) (p)
+#endif
+
+/* random extra sections (if any).  Override
+ * in asm/sections.h */
+#ifndef arch_is_kernel_text
+static inline int arch_is_kernel_text(unsigned long addr)
+{
+	return 0;
+}
+#endif
+
+#ifndef arch_is_kernel_data
+static inline int arch_is_kernel_data(unsigned long addr)
+{
+	return 0;
+}
+#endif
+
+/* U-Boot-specific things begin here */
+
+/* Start of U-Boot text region */
+extern char __text_start[];
+
+/* This marks the end of the text region which must be relocated */
+extern char __image_copy_end[];
+
+/*
+ * This is the U-Boot entry point - prior to relocation it should be same
+ * as __text_start
+ */
+extern void _start(void);
+
+/*
+ * ARM needs to use offsets for symbols, since the values of some symbols
+ * are not resolved prior to relocation (and are just 0). Maybe this can be
+ * resolved, or maybe other architectures are similar, iwc this should be
+ * promoted to an architecture option.
+ */
+#ifdef CONFIG_ARM
+#define CONFIG_SYS_SYM_OFFSETS
+#endif
+
+#ifdef CONFIG_SYS_SYM_OFFSETS
+/* Start/end of the relocation entries, as an offset from _start */
+extern ulong _rel_dyn_start_ofs;
+extern ulong _rel_dyn_end_ofs;
+
+/* Start/end of the relocation symbol table, as an offset from _start */
+extern ulong _dynsym_start_ofs;
+
+/* End of the region to be relocated, as an offset form _start */
+extern ulong _image_copy_end_ofs;
+
+extern ulong _bss_start_ofs;	/* BSS start relative to _start */
+extern ulong _bss_end_ofs;		/* BSS end relative to _start */
+extern ulong _end_ofs;		/* end of image relative to _start */
+
+extern ulong _TEXT_BASE;	/* code start */
+
+#else /* don't use offsets: */
+
+/* Exports from the Linker Script */
+extern ulong __data_end;
+extern ulong __rel_dyn_start;
+extern ulong __rel_dyn_end;
+extern ulong __bss_end;
+
+extern ulong _TEXT_BASE;	/* code start */
+
+#endif
+
+#endif /* _ASM_GENERIC_SECTIONS_H_ */