Re: [PATCH v6 4/6] mmc: sdhci-of-aspeed: Add KUnit tests for phase calculations

[Andrew Jeffery]

On Wed, 6 Jan 2021, at 00:17, Adrian Hunter wrote:
> On 18/12/20 5:53 am, Andrew Jeffery wrote:
> > Converting degrees of phase to logic delays is irritating to test on
> > hardware, so lets exercise the function using KUnit.
> > 
> > Signed-off-by: Andrew Jeffery <andrew@xxxxxxxx>
> > ---
> >  drivers/mmc/host/Kconfig                |  14 ++++
> >  drivers/mmc/host/Makefile               |   1 +
> >  drivers/mmc/host/sdhci-of-aspeed-test.c | 100 ++++++++++++++++++++++++
> >  3 files changed, 115 insertions(+)
> >  create mode 100644 drivers/mmc/host/sdhci-of-aspeed-test.c
> > 
> > diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
> > index 596f32637315..d6f00d1d6251 100644
> > --- a/drivers/mmc/host/Kconfig
> > +++ b/drivers/mmc/host/Kconfig
> > @@ -168,6 +168,20 @@ config MMC_SDHCI_OF_ASPEED
> >  
> >  	  If unsure, say N.
> >  
> > +config MMC_SDHCI_OF_ASPEED_TEST
> > +	bool "Tests for the ASPEED SDHCI driver"
> > +	depends on MMC_SDHCI_OF_ASPEED && KUNIT=y
> > +	help
> > +	  Enable KUnit tests for the ASPEED SDHCI driver. Select this
> > +	  option only if you will boot the kernel for the purpose of running
> > +	  unit tests (e.g. under UML or qemu).
> > +
> > +	  The KUnit tests generally exercise parts of the driver that do not
> > +	  directly touch the hardware, for example, the phase correction
> > +	  calculations.
> > +
> > +	  If unsure, say N.
> > +
> >  config MMC_SDHCI_OF_AT91
> >  	tristate "SDHCI OF support for the Atmel SDMMC controller"
> >  	depends on MMC_SDHCI_PLTFM
> > diff --git a/drivers/mmc/host/Makefile b/drivers/mmc/host/Makefile
> > index 451c25fc2c69..3ee59d5802cf 100644
> > --- a/drivers/mmc/host/Makefile
> > +++ b/drivers/mmc/host/Makefile
> > @@ -90,6 +90,7 @@ obj-$(CONFIG_MMC_SDHCI_DOVE)		+= sdhci-dove.o
> >  obj-$(CONFIG_MMC_SDHCI_TEGRA)		+= sdhci-tegra.o
> >  obj-$(CONFIG_MMC_SDHCI_OF_ARASAN)	+= sdhci-of-arasan.o
> >  obj-$(CONFIG_MMC_SDHCI_OF_ASPEED)	+= sdhci-of-aspeed.o
> > +obj-$(CONFIG_MMC_SDHCI_OF_ASPEED_TEST)	+= sdhci-of-aspeed-test.o
> >  obj-$(CONFIG_MMC_SDHCI_OF_AT91)		+= sdhci-of-at91.o
> >  obj-$(CONFIG_MMC_SDHCI_OF_ESDHC)	+= sdhci-of-esdhc.o
> >  obj-$(CONFIG_MMC_SDHCI_OF_HLWD)		+= sdhci-of-hlwd.o
> > diff --git a/drivers/mmc/host/sdhci-of-aspeed-test.c b/drivers/mmc/host/sdhci-of-aspeed-test.c
> > new file mode 100644
> > index 000000000000..fb79b278fb81
> > --- /dev/null
> > +++ b/drivers/mmc/host/sdhci-of-aspeed-test.c
> > @@ -0,0 +1,100 @@
> > +// SPDX-License-Identifier: GPL-2.0-or-later
> > +/* Copyright (C) 2020 IBM Corp. */
> > +
> > +#include <kunit/test.h>
> > +
> > +#include "sdhci-of-aspeed.c"
> 
> I am not sure including like that is advisable.

Yeah I wasn't convinced by it either, but I was just running the tests under 
qemu and they did what I expected.

> Did you consider instead
> doing it the other way around i.e. adding an include to the bottom of
> sdhci-of-aspeed.c?

No, I didn't. I'll switch to this approach.

Thanks!

Andrew