Re: [PATCH] remoteproc: qcom: Introduce Hexagon V5 based WCSS driver
From: Bjorn Andersson
Date: Thu Jun 07 2018 - 00:22:44 EST
On Wed 06 Jun 21:11 PDT 2018, Vinod wrote:
> On 06-06-18, 09:17, Bjorn Andersson wrote:
> > On Tue 05 Jun 05:56 PDT 2018, Sricharan R wrote:
> >
> > > Hi Vinod,
> > >
> > > On 6/5/2018 11:49 AM, Vinod wrote:
> > > > On 05-06-18, 11:12, Sricharan R wrote:
> > > >
> > > >> +config QCOM_Q6V5_WCSS
> > > >> + tristate "Qualcomm Hexagon based WCSS Peripheral Image Loader"
> > > >> + depends on OF && ARCH_QCOM
> > > >> + depends on QCOM_SMEM
> > > >> + depends on RPMSG_QCOM_SMD || (COMPILE_TEST && RPMSG_QCOM_SMD=n)
> > > >> + depends on RPMSG_QCOM_GLINK_SMEM || RPMSG_QCOM_GLINK_SMEM=n
> > > >
> > > > Is there a reason why it depends on RPMSG_QCOM_GLINK_SMEM=n? What would
> > > > happen if distro wants both this and RPMSG_QCOM_GLINK_SMEM
> > > >
> >
> > It says that QCOM_Q6V5_WCSS either must have a compatible state (i.e.
> > builtin vs builtin, module vs builtin, but not builtin vs module) or
> > that it's disabled, in which case we will hit the stub functions in
> > qcom_glink.h.
> >
> > I.e. this prevents QCOM_Q6V5_WCSS to be compiled builtin when
> > RPMSG_QCOM_GLINK_SMEM is module, as this would give us both stubs and
> > the module.
>
> IIUC, you want to have QCOM_Q6V5_WCSS and RPMSG_QCOM_GLINK_SMEM as
> modules or builtin
>
RPMSG_QCOM_SMD, RPMSG_QCOM_GLINK_SMEM and QCOM_Q6V5_WCSS are all
tristate.
> So, wouldn't Kconfig syntax something like where we say:
> M if RPMSG_QCOM_GLINK_SMEM=m
> bool if RPMSG_QCOM_GLINK_SMEM=y
>
If we ignore SMD for a while we have the following combinations:
glink/wcss
y y - valid
y m - valid
y n - valid
m y - link failure (invalid)
m m - valid
m n - valid
n y - valid (platform uses wcss, but not glink)
n m - valid (-----"-----)
n n - valid
So to distill this we have the two valid cases:
module/no if RPMSG_QCOM_GLINK_SMEM=m
yes/module/no if RPMSG_QCOM_GLINK_SMEM=y
and the way you express that in Kconfig is the somewhat awkward
depends on RPMSG_QCOM_GLINK_SMEM || RPMSG_QCOM_GLINK_SMEM=n
> Which makes it clear that both these have to be same type?
>
They don't have to be of the same type, only of a compatible type.
Regards,
Bjorn