Ð Wed, 26 Jan 2011 16:35:05 -0000 "David Laight" <David.Laight@xxxxxxxxxx> ÐÐÑÐÑ: > > > Also in_le32/out_le32/in_be32/out_be32 are > > architecture-specific AFAIK. > > Isn't the whole patch architecture-specific ? I use this driver on MIPS board right now. :) This core from Synopsys is used in many SOCs with various architectures. > > I'd suggest using readl/writel for LE ops and > > __be32_to_cpu(__raw_readl(addr))/__raw_writel(__cpu_to_be32(b),addr) > > for BE ops. > > Since the ppc doesn't have a byteswap instruction (and the LE > memory transfers might even be slow!) you really don't want to > be doing software byteswap. > > Not to mention the horrific synchronistion instructions > that in_le32() and out_le32() actually contain. > > I didn't find __raw_readl() when I was looking for asm > patterns that byteswapped memory transfers. > > I did find st_le32() and ld_le32() in arch/powerpc/include/asm/swab.h > but that file is actually quite difficult to #include because > there is another swab.h that gets included instead. I see. readl/writel are defined in asm-generic/io.h. So IMHO there should be also le and be versions that can be redefined in arch-specific code. -- Alexander
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