Most of the existing macros don't work with assembler, due to the
use of type casts and C functions from <linux/swab.h>.

This patch abstracts out those operations and provides simple
explicit versions for use in assembly code.

__opcode_is_thumb32() and __opcode_is_thumb16() are also converted
to do bitmask-based testing to avoid confusion if these are used in
assembly code (the assembler typically treats all arithmetic values
as signed).

These changes avoid the need for the compiler to pre-evaluate
constant expressions used to generate opcodes.  By ensuring that
the forms of these expressions can be evaluated directly by the
assembler, we can just stringify the expressions directly into the
asm during the preprocessing pass.  The alternative approach
(passing the evaluated expression via an inline asm "i" constraint)
gets painful because the contents of the asm and the constraints
must be kept in sync.  This makes the resulting macros awkward to
use.

Retaining the C forms of the macros allows more efficient code to
be generated when opcodes are generated programmatically at run-
time, but there is no way to embed run-time-generated opcodes in
asm() blocks.
Signed-off-by: NDave Martin <dave.martin@linaro.org>
Acked-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The existing __mem_to_opcode_thumb32() is incorrect for BE32
platforms.  However, these don't support Thumb-2 kernels, so this
option is not so relevant for those platforms anyway.

This operation is complicated by the lack of unaligned memory
access support prior to ARMv6.

Rather than provide a "working" macro which will probably won't get
used (or worse, will get misused), this patch removes the macro for
BE32 kernels.  People manipulating Thumb opcodes prior to ARMv6
should almost certainly be splitting these operations into
halfwords anyway, using __opcode_thumb32_{first,second,compose}()
and the 16-bit opcode transformations.
Signed-off-by: NDave Martin <dave.martin@linaro.org>
Acked-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This patch adds some endianness-agnostic helpers to convert machine
instructions between canonical integer form and in-memory
representation.

A canonical integer form for representing instructions is also
formalised here.
Signed-off-by: NDave Martin <dave.martin@linaro.org>
Acked-by: NNicolas Pitre <nico@linaro.org>
Tested-by: NJon Medhurst <tixy@yxit.co.uk>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This patch breaks the ARM condition checking code out of nwfpe/fpopcode.{ch}
into a standalone file for opcode operations. It also modifies the code
somewhat for coding style adherence, and adds some temporary variables for
increased readability.
Signed-off-by: NLeif Lindholm <leif.lindholm@arm.com>
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>