On 09/15, Andrew Morton wrote:

On Tue, 15 Sep 2015 12:41:26 -0700 Stephen Boyd [off-list ref] wrote:

quoted

The SMD driver is reading and writing chunks of data to iomem,
and there's an __iowrite32_copy() function for the writing part, but
no __ioread32_copy() function for the reading part. This series
adds __ioread32_copy() and uses it in two places. Andrew is on Cc in
case this should go through the -mm tree. Otherwise the target
of this patch series is SMD, so I've sent it to Andy.

"soc: qcom: smd: Use __ioread32_copy() instead of open-coding it" no
longer applies, because smd_copy_from_fifo() has switched to
readl_relaxed().

Yes. There are some other patches in flight on the mailing list
to this file from me[1]. Those would need to be applied first to
avoid conflicts.

Let's use the __weak macro rather than open-coding it (and convert
__iowrite32_copy() while we're in there).

Yep, I converted the __iowrite32_copy() open-code in there too in
the patch series I mentioned above. See [2].

It's unclear why __iowrite32_copy() is a weak function - nothing
overrides it.  Perhaps we should just take that away rather than
copying it into __ioread32_copy().

Huh? I see that x86 has an implementation in arch/x86/lib/iomap_copy_64.S

__iowrite32_copy() is marked __visible.  I don't actually know what
that does and Andi's d47d5c8194579bc changelog (which sucks the big
one) didn't explain it.  Apparently it has something to do with being
implemented in assembly, but zillions of functions are implemented in
assembly, so why are only two functions marked this way?  Anyway,
__ioread32_copy() is implemented in C so I guess __visible isn't needed
there.

Yeah, I didn't add visible because there isn't an assembly
version of __ioread32_copy() so far. I can remove __weak if
desired. I left it there to match __iowrite32_copy() in case
x86 wanted to override it but we can do that later or never.

[1] http://lkml.kernel.org/g/1441234011-4259-7-git-send-email-sboyd at codeaurora.org
[2] http://lkml.kernel.org/g/1441234011-4259-5-git-send-email-sboyd at codeaurora.org

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