RE: [PATCH v7 5/8] i3c: target: add svc target controller support

Joshua Yeong
2024-03-06T18:26:01Z

> -----Original Message-----
> From: Frank Li <Frank.li@nxp.com>
> Sent: Thursday, March 7, 2024 1:45 AM
> To: Joshua Yeong <joshua.yeong@starfivetech.com>
> Cc: alexandre.belloni@bootlin.com; conor.culhane@silvaco.com;
> devicetree@vger.kernel.org; gregkh@linuxfoundation.org;
> ilpo.jarvinen@linux.intel.com; imx@lists.linux.dev; jirislaby@kernel.org;
> joe@perches.com; krzysztof.kozlowski+dt@linaro.org;
> krzysztof.kozlowski@linaro.org; linux-i3c@lists.infradead.org; linux-
> kernel@vger.kernel.org; linux-serial@vger.kernel.org;
> miquel.raynal@bootlin.com; robh@kernel.org;
> zbigniew.lukwinski@linux.intel.com
> Subject: Re: [PATCH v7 5/8] i3c: target: add svc target controller support
>
> On Wed, Mar 06, 2024 at 04:01:17PM +0000, Joshua Yeong wrote:
> > Hi Frank,
> >
> > > -----Original Message-----
> > > From: linux-i3c <linux-i3c-bounces@lists.infradead.org> On Behalf Of
> > > Frank Li
> > > Sent: Tuesday, February 6, 2024 7:33 AM
> > > To: frank.li@nxp.com
> > > Cc: alexandre.belloni@bootlin.com; conor.culhane@silvaco.com;
> > > devicetree@vger.kernel.org; gregkh@linuxfoundation.org;
> > > ilpo.jarvinen@linux.intel.com; imx@lists.linux.dev;
> > > jirislaby@kernel.org; joe@perches.com;
> > > krzysztof.kozlowski+dt@linaro.org;
> > > krzysztof.kozlowski@linaro.org; linux-i3c@lists.infradead.org;
> > > linux- kernel@vger.kernel.org; linux-serial@vger.kernel.org;
> > > miquel.raynal@bootlin.com; robh@kernel.org;
> > > zbigniew.lukwinski@linux.intel.com
> > > Subject: [PATCH v7 5/8] i3c: target: add svc target controller
> > > support
> > >
> > > Add Silvaco I3C target controller support
> > >
> > > Signed-off-by: Frank Li <Frank.Li@nxp.com>
> > > ---
> > >
> > > Notes:
> > > Change from v2 to v3
> > > - fix build warning
> > >
> > > drivers/i3c/master/Makefile | 2 +-
> > > drivers/i3c/master/svc-i3c-main.c | 35 +-
> > > drivers/i3c/master/svc-i3c-target.c | 776
> >
> > I think putting target mode files under "master" might not make sense.
> > We might have to consider that we may have a "secondary master" mode.
> > Some other ways of splitting or handling of target mode is needed here.
>
> I think name 'master' is not good here. Previously only support 'master'
> mode, it should be fine. Now many controller are dual mode.
>
> And I3C spec use 'controller/target' instead of 'master/slave'. I think
> 'controller' as master are quite confused. It can be master controller and slave
> controller.
>
> Anyway, slave/master may share some code and resource, even only one file.
>
> So far, I think it is fine put under master now. we can rename 'master'
> later when more dual mode controller added.
>
> Frank

I am currently working on secondary-controller mode. I would like to explore if
we can have a different way to implement various modes.

I am guessing that the current inspiration is coming from the existing i2c
framework.

However, I am thinking of having a more generic function to replace the way how
we register the i3c driver. (existing 'i3c_master_register' or
'devm_i3c_target_ctrl_create' from yours) Maybe along the line where we can have
all the modes set in a struct and return to the i3c framework. So we only need 1
API to register all the different modes instead of having one each.

>
> >
> > ...
> >
> > > +
> > > +#define I3C_SCONFIG 0x4
> > > +#define I3C_SCONFIG_SLVENA_MASK BIT(0)
> > > +#define I3C_SCONFIG_OFFLINE_MASK BIT(9)
> > > +#define I3C_SCONFIG_SADDR_MASK GENMASK(31, 25)
> > > +
> > > +#define I3C_SSTATUS 0x8
> > > +#define I3C_SSTATUS_STNOTSTOP_MASK BIT(0)
> > > +#define I3C_SSTATUS_STOP_MASK BIT(10)
> > > +#define I3C_SSTATUS_RX_PEND_MASK BIT(11)
> > > +#define I3C_SSTATUS_TXNOTFULL_MASK BIT(12)
> > > +#define I3C_SSTATUS_DACHG_MASK BIT(13)
> > > +#define I3C_SSTATUS_EVDET_MASK GENMASK(21, 20)
> > > +#define I3C_SSTATUS_EVDET_ACKED 0x3
> > > +#define I3C_SSTATUS_IBIDIS_MASK BIT(24)
> > > +#define I3C_SSTATUS_HJDIS_MASK BIT(27)
> > > +
> >
> > There is couple of space formatting here that requires to be fixed.
> >
> > Cheers,
> > Joshua