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Message-Id: <20191031003154.21969-1-linux@rasmusvillemoes.dk>
Date: Thu, 31 Oct 2019 01:31:49 +0100
From: Rasmus Villemoes <linux@...musvillemoes.dk>
To: linux-arch@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org
Cc: Christophe Leroy <christophe.leroy@....fr>,
Arnd Bergmann <arnd@...db.de>,
Michael Ellerman <mpe@...erman.id.au>,
Benjamin Herrenschmidt <benh@...nel.crashing.org>,
Paul Mackerras <paulus@...ba.org>,
linux-kernel@...r.kernel.org,
Rasmus Villemoes <linux@...musvillemoes.dk>
Subject: [RFC PATCH 0/5] powerpc: make iowrite32be etc. inline
When trying to make the QUICC Engine drivers compile on arm, I
mechanically (with coccinelle) changed out_be32() to iowrite32be()
etc. Christophe pointed out [1][2] that that would pessimize the
powerpc SOCs since the IO accesses now incur a function call
overhead. He asked that I try to make those io accessors inline on
ppc, and this is the best I could come up with.
At first I tried something that wouldn't need to touch anything
outside arch/powerpc/, but I ended up with conditional inclusion of
asm-generic headers and/or duplicating a lot of their contents.
The diffstat may become a little better if kernel/iomap.c can indeed
be removed (due to !CONFIG_PPC_INDIRECT_PIO &&
CONFIG_PPC_INDIRECT_MMIO never happening).
[1] https://lore.kernel.org/lkml/6ee121cf-0e3d-4aa0-2593-fcb00995e429@c-s.fr/
[2] https://lore.kernel.org/lkml/886d5218-6d6b-824c-3ab9-63aafe41ff40@c-s.fr/
Rasmus Villemoes (5):
asm-generic: move pcu_iounmap from iomap.h to pci_iomap.h
asm-generic: employ "ifndef foo; define foo foo" idiom in iomap.h
powerpc: move pci_iounmap() from iomap.c to pci-common.c
powerpc: make pcibios_vaddr_is_ioport() static
powerpc: make iowrite32 and friends static inline when no indirection
arch/powerpc/include/asm/io.h | 172 ++++++++++++++++++++++++++
arch/powerpc/include/asm/pci-bridge.h | 9 --
arch/powerpc/kernel/Makefile | 2 +-
arch/powerpc/kernel/iomap.c | 13 --
arch/powerpc/kernel/pci-common.c | 15 ++-
include/asm-generic/iomap.h | 104 +++++++++++++---
include/asm-generic/pci_iomap.h | 7 ++
7 files changed, 282 insertions(+), 40 deletions(-)
--
2.23.0
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