Re: [PATCH 2/2] soc: ti: pruss: add support for AM18XX/OMAP-L138 PRUSS

[David Lechner]

On 1/15/21 6:52 PM, Suman Anna wrote:
> Hi David,
>
> On 1/4/21 12:30 PM, David Lechner wrote:
> > This adds support for the PRUSS found in AM18XX/OMAP-L138. This PRUSS
> > doesn't have a CFG register, so that is made optional as selected by
> > the device tree compatible string.
> >
> > ARCH_DAVINCI is added in the Kconfig so that the driver can be selected
> > on that platform.
> >
> > Signed-off-by: David Lechner <david@xxxxxxxxxxxxxx>
> > ---
> >   drivers/soc/ti/Kconfig |  2 +-
> >   drivers/soc/ti/pruss.c | 76 ++++++++++++++++++++++++------------------
> >   2 files changed, 45 insertions(+), 33 deletions(-)
> >
> > diff --git a/drivers/soc/ti/Kconfig b/drivers/soc/ti/Kconfig
> > index 7e2fb1c16af1..7a692a21480a 100644
> > --- a/drivers/soc/ti/Kconfig
> > +++ b/drivers/soc/ti/Kconfig
> > @@ -85,7 +85,7 @@ config TI_K3_SOCINFO
> >   
> >   config TI_PRUSS
> >   	tristate "TI PRU-ICSS Subsystem Platform drivers"
> > -	depends on SOC_AM33XX || SOC_AM43XX || SOC_DRA7XX || ARCH_KEYSTONE || ARCH_K3
> > +	depends on ARCH_DAVINCI || SOC_AM33XX || SOC_AM43XX || SOC_DRA7XX || ARCH_KEYSTONE || ARCH_K3
> >   	select MFD_SYSCON
> >   	help
> >   	  TI PRU-ICSS Subsystem platform specific support.
> > diff --git a/drivers/soc/ti/pruss.c b/drivers/soc/ti/pruss.c
> > index 5d6e7132a5c4..bfaf3ff74b01 100644
> > --- a/drivers/soc/ti/pruss.c
> > +++ b/drivers/soc/ti/pruss.c
> > @@ -24,10 +24,12 @@
> >    * struct pruss_private_data - PRUSS driver private data
> >    * @has_no_sharedram: flag to indicate the absence of PRUSS Shared Data RAM
> >    * @has_core_mux_clock: flag to indicate the presence of PRUSS core clock
> > + * @has_cfg: flag to indicate the presence of PRUSS CFG registers
>
> I recommend to change this to a negative flag as the Davinci platforms are the
> only ones that don't have CFG (being the very first SoCs with a PRUSS IP)
> sub-module.

Negative flags hurt my brain. :-)

I was actually thinking about submitting a patch to convert
has_no_sharedram to a positive flag as well. But I understand
the sentiment of only setting the flag true for the odd case
rather than the usual case.

> >    */
> >   struct pruss_private_data {
> >   	bool has_no_sharedram;
> >   	bool has_core_mux_clock;
> > +	bool has_cfg;
> >   };
> >   
> >   static void pruss_of_free_clk_provider(void *data)
> > @@ -239,42 +241,44 @@ static int pruss_probe(struct platform_device *pdev)
> >   		goto rpm_disable;
> >   	}
> >   
>
> And use it here to skip all the cfg code parsing. All the below delta is just
> for the additional indentation for the flag. If you don't like goto's in
> non-error paths, then we can refactor the CFG parse code into a separate function.

Refactoring to a separate function sounds good to me.