> -----Original Message-----
> From: Bjorn Andersson [mailto:bjorn.anders...@linaro.org]
> Sent: Thursday, December 14, 2017 2:30 AM
> To: Loic PALLARDY <loic.palla...@st.com>
> Cc: o...@wizery.com; linux-remotep...@vger.kernel.org; linux-
> ker...@vger.kernel.org; Arnaud POULIQUEN <arnaud.pouliq...@st.com>;
> benjamin.gaign...@linaro.org
> Subject: Re: [PATCH v2 10/16] remoteproc: add memory device registering in
> rproc_add_carveout
>
> On Thu 30 Nov 08:46 PST 2017, Loic Pallardy wrote:
>
> > Add the possibility to associate a memory device to
> > carveout.
> >
> > Due to some memory mapping constraints, remoteproc related memory
> > allocations should be done in a specific memory region.
> > Constraint is not coming from remoteproc firmware (with defined
> > device address), but from remoteproc platform driver itself.
> >
> > In that case, platform driver has to register a carveout region with
> > memory device. Memory device will be used for carveout, vring or buffer
> > allocation accorfing to its name.
> >
> > Signed-off-by: Loic Pallardy <loic.palla...@st.com>
> > ---
> > drivers/remoteproc/remoteproc_core.c | 14 +++++++++++++-
> > drivers/remoteproc/st_remoteproc.c | 2 +-
> > include/linux/remoteproc.h | 3 ++-
> > 3 files changed, 16 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/remoteproc/remoteproc_core.c
> b/drivers/remoteproc/remoteproc_core.c
> > index 76d54bf..2b7effb 100644
> > --- a/drivers/remoteproc/remoteproc_core.c
> > +++ b/drivers/remoteproc/remoteproc_core.c
> > @@ -964,17 +964,29 @@ static int rproc_handle_carveout(struct rproc
> *rproc,
> > * rproc_add_carveout() - register an allocated carveout region
> > * @rproc: rproc handle
> > * @mem: memory entry to register
> > + * @memdev: true if carveout shoult be associated to a memory device
> > *
> > * This function registers specified memory entry in @rproc carveouts list.
> > * Specified carveout should have been allocated before registering.
> > */
> > -int rproc_add_carveout(struct rproc *rproc, struct rproc_mem_entry
> *mem)
> > +int rproc_add_carveout(struct rproc *rproc, struct rproc_mem_entry
> *mem, bool memdev)
> > {
> > + struct rproc_memdev *memd;
> > +
> > if (!rproc || !mem)
> > return -EINVAL;
> >
> > mem->priv = (void *)CARVEOUT_EXTERNAL;
> >
> > + if (memdev) {
> > + memd = rproc_memdev_add(rproc, mem);
>
> But this would likely cause the memory-region to be remapped twice, once
> by the
> caller and once by the dmam_declare_coherent_memory().
Yes if already mapped by driver
>
> > + if (IS_ERR(memd))
> > + return -ENOMEM;
> > + mem->memdev = memd;
> > + } else {
> > + mem->memdev = NULL;
> > + }
> > +
> > list_add_tail(&mem->node, &rproc->carveouts);
> >
> > return 0;
> > diff --git a/drivers/remoteproc/st_remoteproc.c
> b/drivers/remoteproc/st_remoteproc.c
> > index 1549ce8..da42ec9 100644
> > --- a/drivers/remoteproc/st_remoteproc.c
> > +++ b/drivers/remoteproc/st_remoteproc.c
> > @@ -286,7 +286,7 @@ static int st_rproc_parse_dt(struct platform_device
> *pdev)
> > return -EBUSY;
> > }
> >
> > - rproc_add_carveout(rproc, mem);
> > + rproc_add_carveout(rproc, mem, false);
>
> So when memdev is false this should imply that "mem" has not been
> remapped already. Which I think would be better captured by not
> overloading the add_carveout function.
>
So you propose to have to different interfaces: one for memory device registry
and a second for carveout registry?
In that case user will do memory mapping either by its own or by using memory
device registration.
Regards,
Loic
> Regards,
> Bjorn
