On Wed, 2022-08-03 at 17:37 -0600, Rob Herring wrote: > On Wed, Aug 03, 2022 at 09:24:21AM +0800, Liu Ying wrote: > > Freescale i.MX8qxp pixel link MSI bus is a simple memory-mapped > > bus. > > It is used to access peripherals in i.MX8qm/qxp imaging, LVDS, MIPI > > DSI and HDMI TX subsystems, like I2C controller, PWM controller, > > MIPI DSI controller and Control and Status Registers (CSR) module. > > > > Reference simple-pm-bus bindings and add Freescale i.MX8qxp pixel > > link MSI bus specific bindings. > > > > Signed-off-by: Liu Ying <victor.liu@xxxxxxx> > > --- > > v1->v2: > > Address Krzysztof's comments: > > * Add a select to explicitly select the MSI bus dt-binding. > > * List 'simple-pm-bus' explicitly as one item of compatible > > strings. > > * Require compatible and reg properties. > > * Put reg property just after compatible property in example. > > > > .../bus/fsl,imx8qxp-pixel-link-msi-bus.yaml | 97 > > +++++++++++++++++++ > > 1 file changed, 97 insertions(+) > > create mode 100644 > > Documentation/devicetree/bindings/bus/fsl,imx8qxp-pixel-link-msi- > > bus.yaml > > > > diff --git a/Documentation/devicetree/bindings/bus/fsl,imx8qxp- > > pixel-link-msi-bus.yaml > > b/Documentation/devicetree/bindings/bus/fsl,imx8qxp-pixel-link-msi- > > bus.yaml > > new file mode 100644 > > index 000000000000..358c032041e5 > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/bus/fsl,imx8qxp-pixel-link- > > msi-bus.yaml > > @@ -0,0 +1,97 @@ > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > > +%YAML 1.2 > > +--- > > +$id: > > https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fdevicetree.org%2Fschemas%2Fbus%2Ffsl%2Cimx8qxp-pixel-link-msi-bus.yaml%23&data=05%7C01%7Cvictor.liu%40nxp.com%7C3ce426916ec64ab9089708da75a92be5%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C637951666695217514%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=qKEVrlyUkszZ%2FQyYeTIF9AoEqYvCiJjwVTIflzYiyOY%3D&reserved=0 > > +$schema: > > https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fdevicetree.org%2Fmeta-schemas%2Fcore.yaml%23&data=05%7C01%7Cvictor.liu%40nxp.com%7C3ce426916ec64ab9089708da75a92be5%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C637951666695217514%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=hhwFjqe3xmBtdrbG0EwtpGv%2By3jD%2Bm6OXN3hK6WQw4A%3D&reserved=0 > > + > > +title: Freescale i.MX8qxp Pixel Link Medium Speed Interconnect > > (MSI) Bus > > + > > +maintainers: > > + - Liu Ying <victor.liu@xxxxxxx> > > + > > +description: | > > + i.MX8qxp pixel link MSI bus is used to control settings of PHYs, > > I/Os > > + sitting together with the PHYs. It is not the same as the MSI > > bus coming > > + from i.MX8 System Controller Unit (SCU) which is used to control > > power, > > + clock and reset through the i.MX8 Distributed Slave System > > Controller (DSC). > > + > > + i.MX8qxp pixel link MSI bus is a simple memory-mapped bus. Two > > input clocks, > > + that is, MSI clock and AHB clock, need to be enabled so that > > peripherals > > + connected to the bus can be accessed. Also, the bus is part of a > > power > > + domain. The power domain needs to be enabled before the > > peripherals can > > + be accessed. > > + > > + Peripherals in i.MX8qm/qxp imaging, LVDS, MIPI DSI and HDMI TX > > subsystems, > > + like I2C controller, PWM controller, MIPI DSI controller and > > Control and > > + Status Registers (CSR) module, are accessed through the bus. > > + > > + The i.MX System Controller Firmware (SCFW) owns and uses the > > i.MX8qm/qxp > > + pixel link MSI bus controller and does not allow SCFW user to > > control it. > > + So, the controller's registers cannot be accessed by SCFW user. > > Hence, > > + the interrupts generated by the controller don't make any sense > > from SCFW > > + user's point of view. > > + > > +allOf: > > + - $ref: simple-pm-bus.yaml# > > + > > +# We need a select here so we don't match all nodes with 'simple- > > pm-bus'. > > +select: > > + properties: > > + compatible: > > + contains: > > + enum: > > + - fsl,imx8qxp-display-pixel-link-msi-bus > > + - fsl,imx8qm-display-pixel-link-msi-bus > > + required: > > + - compatible > > + > > +properties: > > + compatible: > > + items: > > + - enum: > > + - fsl,imx8qxp-display-pixel-link-msi-bus > > + - fsl,imx8qm-display-pixel-link-msi-bus > > + - const: simple-pm-bus > > + > > + reg: > > + maxItems: 1 > > + > > + interrupts: > > + maxItems: 1 > > + > > + clocks: > > + items: > > + - description: master gated clock from system > > + - description: AHB clock > > + > > + clock-names: > > + items: > > + - const: msi > > + - const: ahb > > + > > +required: > > + - compatible > > + - reg > > + - clocks > > + - clock-names > > + - power-domains > > + > > +unevaluatedProperties: false > > No child nodes allowed? Should be allowed. I'll add a pattern property to allow child nodes. Thanks, Liu Ying > > > + > > +examples: > > + - | > > + #include <dt-bindings/clock/imx8-lpcg.h> > > + #include <dt-bindings/firmware/imx/rsrc.h> > > + bus@56200000 { > > + compatible = "fsl,imx8qxp-display-pixel-link-msi-bus", > > "simple-pm-bus"; > > + reg = <0x56200000 0x20000>; > > + #address-cells = <1>; > > + #size-cells = <1>; > > + interrupt-parent = <&dc0_irqsteer>; > > + interrupts = <320>; > > + ranges; > > + clocks = <&dc0_disp_ctrl_link_mst0_lpcg IMX_LPCG_CLK_4>, > > + <&dc0_disp_ctrl_link_mst0_lpcg IMX_LPCG_CLK_4>; > > + clock-names = "msi", "ahb"; > > + power-domains = <&pd IMX_SC_R_DC_0>; > > + }; > > -- > > 2.25.1 > > > >
