Re: [PATCH v3 3/4] ata: Add APM X-Gene SoC SATA host controller driver

Arnd Bergmann
2013-11-21T13:20:28Z

On Saturday 16 November 2013, Loc Ho wrote:

> >
> > config SATA_XGENE
> > tristate "APM X-Gene 6.0Gbps SATA host controller support"
> > depends on ARM64 || COMPILE_TEST
> > ...
> >
> [Loc Ho]
> Okay. How about this?
>
> depends on ARM64 || COMPILE_TEST
> select SATA_XGENE_PHY && SATA_AHCI_PLATFORM

I think you already found the mistake withis and corrected this in v4.

> > The interface you are looking for is pr_debug() or dev_dbg(), which get
> > built-in only if the DEBUG macro is set.
> >
> > In a lot of cases, it's actually best to remove debug output like this from
> > the driver once you have it working -- whoever is debugging problems in
> > the driver next might need completely different debugging information or
> > can add them back easily if needed.
> >
> > It's your choice if you want to use pr_debug() or remove that output
> > entirely. If you remove it, best remove the helper functions entirely
> > and use readl/writel directly.
> [Loc Ho]
> I would like to keep this function for now until this driver actual
> being used in production. I will use pr_debug.

Ok.

> >> diff --git a/drivers/ata/sata_xgene.h b/drivers/ata/sata_xgene.h
> >> new file mode 100644
> >> index 0000000..51e73f6
> >> --- /dev/null
> >> +++ b/drivers/ata/sata_xgene.h
> >
> > This file should probably just be folded into the driver, since it contains no
> > interfaces between modules, just internal definitions.
> [Loc Ho]
> I can get rip this header file now. But in the future I may need to
> add this back as I intended this driver to also support running from
> our co-processor (ARMv7 32-bit). For that, I will need anothe file and
> other function that will need knowledge of the context structure and
> etc.

Hmm, is the code for that coprocessor compiled from the kernel source?
If not, it shouldn't really make a difference as it won't live in a shared
code repository.

Arnd