The current way to calculate the compressed image position works
with the OSELAS toolchains, but not with the Debian/Ubuntu toolchains.
For these toolchains &image_end_marker already returns the correct
address, adding global_variable_offset() to it is wrong.

The solution seems to be to put the image_end_marker into a different
object file so that the compiler cannot play any tricks to resolve
the address internally in the object file.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

We collected most linker variable declarations in asm/sections.h, so
move __exceptions_start/__exceptions_stop there aswell.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

Now that ld_var is no longer used it can be removed.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

The ld_var solves the issue that when compiled with -pie the linker
provided variables are all 0x0. This mechanism however refuses to
compile with aarch64 support.

This patch replaces the ld_var mechanism with a nice little trick
learned from U-Boot: Instead of using linker provided variables
directly with "__bss_start = ." we put a zero size array into
a separate section and use the address of that array instead of
the linker variable. This properly works before relocation.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

With relocatable binaries the linker is not able to supply absolute
addresses. These only get available when the relocation function is
being run. Since for early initialization we need some variables
before relocation, we supply them relatively to some known address
in the binary. This means that the variables have to be converted
to absolute addresses during runtime.

This patch adds a C macro and an assembly macro to calculate the
variables during runtime.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

The file location and variable names from the Linux Kernel have been
used here.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>