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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Jan 17, 2024 at 02:13:42PM -0600, Rob Herring wrote: > On Tue, Jan 16, 2024 at 07:11:40PM +0530, Devarsh Thakkar wrote: > > Add support for using TI Keystone DSS hardware present in display > > sharing mode. > > > > TI Keystone DSS hardware supports partitioning of resources between > > multiple hosts as it provides separate register space and unique > > interrupt line to each host. > > > > The DSS hardware can be used in shared mode in such a way that one or > > more of video planes can be owned by Linux wherease other planes can be > > owned by remote cores. > > > > One or more of the video ports can be dedicated exclusively to a > > processing core, wherease some of the video ports can be shared between > > two hosts too with only one of them having write access. > > > > Signed-off-by: Devarsh Thakkar > > --- > > .../bindings/display/ti/ti,am65x-dss.yaml | 82 +++++++++++++++++++ > > 1 file changed, 82 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/display/ti/ti,am65x-dss.yaml b/Documentation/devicetree/bindings/display/ti/ti,am65x-dss.yaml > > index 55e3e490d0e6..d9bc69fbf1fb 100644 > > --- a/Documentation/devicetree/bindings/display/ti/ti,am65x-dss.yaml > > +++ b/Documentation/devicetree/bindings/display/ti/ti,am65x-dss.yaml > > @@ -112,6 +112,86 @@ properties: > > Input memory (from main memory to dispc) bandwidth limit in > > bytes per second > > > > + ti,dss-shared-mode: > > + type: boolean > > + description: > > + TI DSS7 supports sharing of display between multiple hosts > > + as it provides separate register space for display configuration and > > + unique interrupt line to each host. > > If you care about line breaks, you need '|'. > > > + One of the host is provided access to the global display > > + configuration labelled as "common" region of DSS allows that host > > + exclusive access to global registers of DSS while other host can > > + configure the display for it's usage using a separate register > > + space labelled as "common1". > > + The DSS resources can be partitioned in such a way that one or more > > + of the video planes are owned by Linux whereas other video planes > > Your h/w can only run Linux? > > What if you want to use this same binding to define the configuration to > the 'remote processor'? You can easily s/Linux/the OS/, but it all > should be reworded to describe things in terms of the local processor. > > > + can be owned by a remote core. > > + The video port controlling these planes acts as a shared video port > > + and it can be configured with write access either by Linux or the > > + remote core in which case Linux only has read-only access to that > > + video port. > > What is the purpose of this property when all the other properties are > required? > > > + > > + ti,dss-shared-mode-planes: > > + description: > > + The video layer that is owned by processing core running Linux. > > + The display driver running from Linux has exclusive write access to > > + this video layer. > > + $ref: /schemas/types.yaml#/definitions/string > > + enum: [vidl, vid] > > + > > + ti,dss-shared-mode-vp: > > + description: > > + The video port that is being used in context of processing core > > + running Linux with display susbsytem being used in shared mode. > > + This can be owned either by the processing core running Linux in > > + which case Linux has the write access and the responsibility to > > + configure this video port and the associated overlay manager or > > + it can be shared between core running Linux and a remote core > > + with remote core provided with write access to this video port and > > + associated overlay managers and remote core configures and drives > > + this video port also feeding data from one or more of the > > + video planes owned by Linux, with Linux only having read-only access > > + to this video port and associated overlay managers. > > + > > + $ref: /schemas/types.yaml#/definitions/string > > + enum: [vp1, vp2] > > + > > + ti,dss-shared-mode-common: > > + description: > > + The DSS register region owned by processing core running Linux. > > + $ref: /schemas/types.yaml#/definitions/string > > + enum: [common, common1] > > + > > + ti,dss-shared-mode-vp-owned: > > + description: > > + This tells whether processing core running Linux has write access to > > + the video ports enlisted in ti,dss-shared-mode-vps. > > + $ref: /schemas/types.yaml#/definitions/uint32 > > + enum: [0, 1] > > This can be boolean. Do writes abort or just get ignored? The latter can > be probed and doesn't need a property. > > > + > > + ti,dss-shared-mode-plane-zorder: > > + description: > > + The zorder of the planes owned by Linux. > > + For the scenario where Linux is not having write access to associated > > + video port, this field is just for > > + informational purpose to enumerate the zorder configuration > > + being used by remote core. > > + > > + $ref: /schemas/types.yaml#/definitions/uint32 > > + enum: [0, 1] > > I don't understand how 0 or 1 defines Z-order. > > > + > > +dependencies: > > + ti,dss-shared-mode: [ 'ti,dss-shared-mode-planes', 'ti,dss-shared-mode-vp', > > + 'ti,dss-shared-mode-plane-zorder', 'ti,dss-shared-mode-vp-owned'] > > + ti,dss-shared-mode-vp: ['ti,dss-shared-mode', 'ti,dss-shared-mode-planes', > > + 'ti,dss-shared-mode-plane-zorder', 'ti,dss-shared-mode-vp-owned'] > > + ti,dss-shared-mode-planes: ['ti,dss-shared-mode', 'ti,dss-shared-mode-vp', > > + 'ti,dss-shared-mode-plane-zorder', 'ti,dss-shared-mode-vp-owned'] > > + ti,dss-shared-mode-plane-zorder: ['ti,dss-shared-mode-planes', 'ti,dss-shared-mode-vp', > > + 'ti,dss-shared-mode', 'ti,dss-shared-mode-vp-owned'] > > + ti,dss-shared-mode-vp-owned: ['ti,dss-shared-mode-planes', 'ti,dss-shared-mode-vp', > > + 'ti,dss-shared-mode', 'ti,dss-shared-mode-plane-zorder'] > > + > > allOf: > > - if: > > properties: > > @@ -123,6 +203,8 @@ allOf: > > ports: > > properties: > > port@0: false > > + ti,dss-shared-mode-vp: > > + enum: [vp2] > > This should throw a warning. You just defined a property called 'enum'. Indeed it does. Test your bindings before sending. ../Documentation/devicetree/bindings/display/ti/ti,am65x-dss.yaml:204:35: [error] empty value in block mapp ing (empty-values) CHKDT Documentation/devicetree/bindings/processed-schema.json /home/rob/proj/linux-dt/Documentation/devicetree/bindings/display/ti/ti,am65x-dss.yaml: allOf:0:then:proper ties:ports:properties:ti,dss-shared-mode-vp: None is not of type 'object', 'boolean' from schema $id: http://json-schema.org/draft-07/schema# /home/rob/proj/linux-dt/Documentation/devicetree/bindings/display/ti/ti,am65x-dss.yaml: allOf:0:then:proper ties:ports:properties:enum: ['vp2'] is not of type 'object', 'boolean' from schema $id: http://json-schema.org/draft-07/schema# /home/rob/proj/linux-dt/Documentation/devicetree/bindings/display/ti/ti,am65x-dss.yaml: allOf:0:then:proper ties:ports:properties: 'enum' should not be valid under {'$ref': '#/definitions/json-schema-prop-names'} hint: A json-schema keyword was found instead of a DT property name. from schema $id: http://devicetree.org/meta-schemas/keywords.yaml# /home/rob/proj/linux-dt/Documentation/devicetree/bindings/display/ti/ti,am65x-dss.yaml: allOf:0:then:proper ties:ports:properties:ti,dss-shared-mode-vp: None is not of type 'object', 'boolean' from schema $id: http://devicetree.org/meta-schemas/keywords.yaml# /home/rob/proj/linux-dt/Documentation/devicetree/bindings/display/ti/ti,am65x-dss.yaml: allOf:0:then:proper ties:ports:properties:enum: ['vp2'] is not of type 'object', 'boolean' from schema $id: http://devicetree.org/meta-schemas/keywords.yaml# _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel