[RFC PATCH 0/4] ARM: Unify const-swabbing and conditional asm
Dave Martin
Dave.Martin at arm.com
Wed Oct 9 10:29:49 EDT 2013
There are a few things in assembler.h that would be useful with
inline asm, but currently assembler.h refuses to be included into C
files.
This refactoring provides a place to put const swabbing helpers, which
can then be used in inline asm and other places (I recycle and share
the code from <asm/opcodes.h>).
The final patch modifies the CCI driver to use the new
__asm_cpu_to_le32() helper, based closely on Victor Kamensky's recent
fix for BE8. This allows us to avoid some unneeded ifdeffery.
Comments?
These patches are untested, but I have build-tested the CCI driver in
LE and BE32 configurations, which produces the following change in the
generated code:
e0400001 sub r0, r0, r1
e5900004 ldr r0, [r0, #4]
-e3a03003 mov r3, #3
+e3a03403 mov r3, #50331648 ; 0x3000000
e5803000 str r3, [r0]
e28f1024 add r1, pc, #36 ; 0x24
e5910000 ldr r0, [r1]
e7900001 ldr r0, [r0, r1]
e590100c ldr r1, [r0, #12]
-e3110001 tst r1, #1
+e3110401 tst r1, #16777216 ; 0x1000000
1afffffc bne 288 <cci_port_not_found+0x44>
e3a00000 mov r0, #0
e12fff1e bx lr
Dave Martin (4):
ARM: Allow assembler.h to be used with inline asm
ARM: Add common compile-time swab32 for asm code
ARM: Add const cpu_to_le32 for asm
drivers/bus: arm-cci: Fix CCI enable code for BE32
arch/arm/include/asm/assembler.h | 41 ++++++++++++++++++++++++++++++++++----
arch/arm/include/asm/opcodes.h | 9 +++------
drivers/bus/arm-cci.c | 6 ++++--
3 files changed, 44 insertions(+), 12 deletions(-)
--
1.7.9.5
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