All of lore.kernel.org
 help / color / mirror / Atom feed
From: Dave.Martin@arm.com (Dave Martin)
To: linux-arm-kernel@lists.infradead.org
Subject: [RFC PATCH 0/4] ARM: Unify const-swabbing and conditional asm
Date: Wed,  9 Oct 2013 15:29:49 +0100	[thread overview]
Message-ID: <1381328993-12724-1-git-send-email-Dave.Martin@arm.com> (raw)

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

             reply	other threads:[~2013-10-09 14:29 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-10-09 14:29 Dave Martin [this message]
2013-10-09 14:29 ` [RFC PATCH 1/4] ARM: Allow assembler.h to be used with inline asm Dave Martin
2013-10-09 14:42   ` Russell King - ARM Linux
2013-10-09 15:00     ` Dave Martin
2013-10-09 15:32       ` Nicolas Pitre
2013-10-09 14:29 ` [RFC PATCH 2/4] ARM: Add common compile-time swab32 for asm code Dave Martin
2013-10-09 14:29 ` [RFC PATCH 3/4] ARM: Add const cpu_to_le32 for asm Dave Martin
2013-10-09 14:29 ` [RFC PATCH 4/4] drivers/bus: arm-cci: Fix CCI enable code for BE32 Dave Martin

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1381328993-12724-1-git-send-email-Dave.Martin@arm.com \
    --to=dave.martin@arm.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.