On Tue, Dec 1, 2020 at 5:43 PM Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> wrote: > > Hi Rob, > > On Mon, Nov 30, 2020 at 10:33:21AM -0700, Rob Herring wrote: > > On Thu, Nov 26, 2020 at 02:06:28PM -0700, Mathieu Poirier wrote: > > > This patch adds a binding to guide the remoteproc core on how to deal with > > > remote processors in two cases: > > > > > > 1) When an application holding a reference to a remote processor character > > > device interface crashes. > > > > > > 2) when the platform driver for a remote processor is removed. > > > > > > In both cases if "autonomous-on-core-reboot" is specified in the remote > > > processor DT node, the remoteproc core will detach the remote processor > > > rather than switching it off. > > > > > > Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> > > > --- > > > .../bindings/remoteproc/remoteproc-core.yaml | 25 +++++++++++++++++++ > > > 1 file changed, 25 insertions(+) > > > create mode 100644 Documentation/devicetree/bindings/remoteproc/remoteproc-core.yaml > > > > > > diff --git a/Documentation/devicetree/bindings/remoteproc/remoteproc-core.yaml b/Documentation/devicetree/bindings/remoteproc/remoteproc-core.yaml > > > new file mode 100644 > > > index 000000000000..3032734f42a3 > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/remoteproc/remoteproc-core.yaml > > > @@ -0,0 +1,25 @@ > > > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) > > > +%YAML 1.2 > > > +--- > > > +$id: "http://devicetree.org/schemas/remoteproc/remoteproc-core.yaml#"; > > > +$schema: "http://devicetree.org/meta-schemas/core.yaml#"; > > > + > > > +title: Binding for the remoteproc core applicable to all remote processors > > > + > > > +maintainers: > > > + - Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> > > > + - Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> > > > + > > > +description: > > > + This document defines the binding recognised by the remoteproc core that can > > > + be used by any remote processor in the subsystem. > > > + > > > +properties: > > > + autonomous-on-core-reboot: > > > + $ref: /schemas/types.yaml#/definitions/flag > > > + description: > > > + Used in two situations, i.e when a user space application releases the > > > + handle it has on the remote processor's character driver interface and > > > + when a remote processor's platform driver is being removed. If defined, > > > + this flag instructs the remoteproc core to detach the remote processor > > > + rather than turning it off. > > > > Userspace? character driver? platform driver? remoteproc core? Please > > explain this without OS specific terms. > > The remoteproc state machine is gaining in complexity and having technical terms > in the binding's description helps understand when and how it should be used. I > could make it more generic but that will lead to confusion and abuse. Explaining in Linux specific terms will confuse any other OS user. > Should I > make it "rproc,autonomous-on-core-reboot" ? No, 'rproc' is not a vendor. > > > > Seems to me this would be implied by functionality the remote proc > > provides. > > Exactly - this binding is used by the remoteproc core itself. It is specified > in the remote processor DT nodes but the individual platform drivers don't do > anything with it - the core takes care of enacting the desired behavior on their > behalf. Otherwise each platform driver would end up adding the same code, which > nobody wants to see happening. The platform drivers just need to set a flag to enable some behavior that the core code checks and handles. That should be 1 to a few lines in the drivers. It's not really any different, just a question of where the flag lives. Rob
