[PATCH v4 1/4] dt-bindings: mfd: aspeed-lpc: Convert to YAML schema

From: Chia-Wei Wang
Date: Mon Sep 13 2021 - 02:03:26 EST


Convert the bindings of Aspeed LPC from text file into YAML schema.

Signed-off-by: Chia-Wei Wang <chiawei_wang@xxxxxxxxxxxxxx>
---
.../devicetree/bindings/mfd/aspeed-lpc.txt | 157 ---------------
.../devicetree/bindings/mfd/aspeed-lpc.yaml | 187 ++++++++++++++++++
2 files changed, 187 insertions(+), 157 deletions(-)
delete mode 100644 Documentation/devicetree/bindings/mfd/aspeed-lpc.txt
create mode 100644 Documentation/devicetree/bindings/mfd/aspeed-lpc.yaml

diff --git a/Documentation/devicetree/bindings/mfd/aspeed-lpc.txt b/Documentation/devicetree/bindings/mfd/aspeed-lpc.txt
deleted file mode 100644
index 936aa108eab4..000000000000
--- a/Documentation/devicetree/bindings/mfd/aspeed-lpc.txt
+++ /dev/null
@@ -1,157 +0,0 @@
-======================================================================
-Device tree bindings for the Aspeed Low Pin Count (LPC) Bus Controller
-======================================================================
-
-The LPC bus is a means to bridge a host CPU to a number of low-bandwidth
-peripheral devices, replacing the use of the ISA bus in the age of PCI[0]. The
-primary use case of the Aspeed LPC controller is as a slave on the bus
-(typically in a Baseboard Management Controller SoC), but under certain
-conditions it can also take the role of bus master.
-
-The LPC controller is represented as a multi-function device to account for the
-mix of functionality, which includes, but is not limited to:
-
-* An IPMI Block Transfer[2] Controller
-
-* An LPC Host Controller: Manages LPC functions such as host vs slave mode, the
- physical properties of some LPC pins, configuration of serial IRQs, and
- APB-to-LPC bridging amonst other functions.
-
-* An LPC Host Interface Controller: Manages functions exposed to the host such
- as LPC firmware hub cycles, configuration of the LPC-to-AHB mapping, UART
- management and bus snoop configuration.
-
-* A set of SuperIO[3] scratch registers: Enables implementation of e.g. custom
- hardware management protocols for handover between the host and baseboard
- management controller.
-
-Additionally the state of the LPC controller influences the pinmux
-configuration, therefore the host portion of the controller is exposed as a
-syscon as a means to arbitrate access.
-
-[0] http://www.intel.com/design/chipsets/industry/25128901.pdf
-[1] https://www.renesas.com/en-sg/doc/products/mpumcu/001/rej09b0078_h8s2168.pdf?key=7c88837454702128622bee53acbda8f4
-[2] https://www.intel.com/content/dam/www/public/us/en/documents/product-briefs/ipmi-second-gen-interface-spec-v2-rev1-1.pdf
-[3] https://en.wikipedia.org/wiki/Super_I/O
-
-Required properties
-===================
-
-- compatible: One of:
- "aspeed,ast2400-lpc-v2", "simple-mfd", "syscon"
- "aspeed,ast2500-lpc-v2", "simple-mfd", "syscon"
- "aspeed,ast2600-lpc-v2", "simple-mfd", "syscon"
-
-- reg: contains the physical address and length values of the Aspeed
- LPC memory region.
-
-- #address-cells: <1>
-- #size-cells: <1>
-- ranges: Maps 0 to the physical address and length of the LPC memory
- region
-
-Example:
-
-lpc: lpc@1e789000 {
- compatible = "aspeed,ast2500-lpc-v2", "simple-mfd", "syscon";
- reg = <0x1e789000 0x1000>;
-
- #address-cells = <1>;
- #size-cells = <1>;
- ranges = <0x0 0x1e789000 0x1000>;
-
- lpc_snoop: lpc-snoop@0 {
- compatible = "aspeed,ast2600-lpc-snoop";
- reg = <0x0 0x80>;
- interrupts = <GIC_SPI 144 IRQ_TYPE_LEVEL_HIGH>;
- snoop-ports = <0x80>;
- };
-};
-
-
-LPC Host Interface Controller
--------------------
-
-The LPC Host Interface Controller manages functions exposed to the host such as
-LPC firmware hub cycles, configuration of the LPC-to-AHB mapping, UART
-management and bus snoop configuration.
-
-Required properties:
-
-- compatible: One of:
- "aspeed,ast2400-lpc-ctrl";
- "aspeed,ast2500-lpc-ctrl";
- "aspeed,ast2600-lpc-ctrl";
-
-- reg: contains offset/length values of the host interface controller
- memory regions
-
-- clocks: contains a phandle to the syscon node describing the clocks.
- There should then be one cell representing the clock to use
-
-Optional properties:
-
-- memory-region: A phandle to a reserved_memory region to be used for the LPC
- to AHB mapping
-
-- flash: A phandle to the SPI flash controller containing the flash to
- be exposed over the LPC to AHB mapping
-
-Example:
-
-lpc_ctrl: lpc-ctrl@80 {
- compatible = "aspeed,ast2500-lpc-ctrl";
- reg = <0x80 0x80>;
- clocks = <&syscon ASPEED_CLK_GATE_LCLK>;
- memory-region = <&flash_memory>;
- flash = <&spi>;
-};
-
-LPC Host Controller
--------------------
-
-The Aspeed LPC Host Controller configures the Low Pin Count (LPC) bus behaviour
-between the host and the baseboard management controller. The registers exist
-in the "host" portion of the Aspeed LPC controller, which must be the parent of
-the LPC host controller node.
-
-Required properties:
-
-- compatible: One of:
- "aspeed,ast2400-lhc";
- "aspeed,ast2500-lhc";
- "aspeed,ast2600-lhc";
-
-- reg: contains offset/length values of the LHC memory regions. In the
- AST2400 and AST2500 there are two regions.
-
-Example:
-
-lhc: lhc@a0 {
- compatible = "aspeed,ast2500-lhc";
- reg = <0xa0 0x24 0xc8 0x8>;
-};
-
-LPC reset control
------------------
-
-The UARTs present in the ASPEED SoC can have their resets tied to the reset
-state of the LPC bus. Some systems may chose to modify this configuration.
-
-Required properties:
-
- - compatible: One of:
- "aspeed,ast2600-lpc-reset";
- "aspeed,ast2500-lpc-reset";
- "aspeed,ast2400-lpc-reset";
-
- - reg: offset and length of the IP in the LHC memory region
- - #reset-controller indicates the number of reset cells expected
-
-Example:
-
-lpc_reset: reset-controller@98 {
- compatible = "aspeed,ast2500-lpc-reset";
- reg = <0x98 0x4>;
- #reset-cells = <1>;
-};
diff --git a/Documentation/devicetree/bindings/mfd/aspeed-lpc.yaml b/Documentation/devicetree/bindings/mfd/aspeed-lpc.yaml
new file mode 100644
index 000000000000..4e3862cf2a4b
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/aspeed-lpc.yaml
@@ -0,0 +1,187 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+# # Copyright (c) 2021 Aspeed Tehchnology Inc.
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mfd/aspeed-lpc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Aspeed Low Pin Count (LPC) Bus Controller
+
+maintainers:
+ - Andrew Jeffery <andrew@xxxxxxxx>
+ - Chia-Wei Wang <chiawei_wang@xxxxxxxxxxxxxx>
+
+description:
+ The LPC bus is a means to bridge a host CPU to a number of low-bandwidth
+ peripheral devices, replacing the use of the ISA bus in the age of PCI[0]. The
+ primary use case of the Aspeed LPC controller is as a slave on the bus
+ (typically in a Baseboard Management Controller SoC), but under certain
+ conditions it can also take the role of bus master.
+
+ The LPC controller is represented as a multi-function device to account for the
+ mix of functionality, which includes, but is not limited to
+
+ * An IPMI Block Transfer[2] Controller
+
+ * An LPC Host Interface Controller manages functions exposed to the host such
+ as LPC firmware hub cycles, configuration of the LPC-to-AHB mapping, UART
+ management and bus snoop configuration.
+
+ * A set of SuperIO[3] scratch registers enableing implementation of e.g. custom
+ hardware management protocols for handover between the host and baseboard
+ management controller.
+
+ Additionally the state of the LPC controller influences the pinmux
+ configuration, therefore the host portion of the controller is exposed as a
+ syscon as a means to arbitrate access.
+
+properties:
+ compatible:
+ items:
+ - enum:
+ - aspeed,ast2400-lpc-v2
+ - aspeed,ast2500-lpc-v2
+ - aspeed,ast2600-lpc-v2
+ - const: simple-mfd
+ - const: syscon
+
+ reg:
+ maxItems: 1
+
+ "#address-cells":
+ const: 1
+
+ "#size-cells":
+ const: 1
+
+ ranges: true
+
+patternProperties:
+ "^lpc-ctrl@[0-9a-f]+$":
+ type: object
+
+ description:
+ The LPC Host Interface Controller manages functions exposed to the host such as
+ LPC firmware hub cycles, configuration of the LPC-to-AHB mapping, UART management
+ and bus snoop configuration.
+
+ properties:
+ comptabile:
+ items:
+ - enum:
+ - aspeed,ast2400-lpc-ctrl
+ - aspeed,ast2500-lpc-ctrl
+ - aspeed,ast2600-lpc-ctrl
+
+ reg:
+ maxItems: 1
+
+ clocks:
+ maxItems: 1
+
+ memory-region:
+ $ref: /schemas/types.yaml#/definitions/phandle
+ description: A reserved_memory region to be used for the LPC to AHB mapping
+
+ flash:
+ $ref: /schemas/types.yaml#/definitions/phandle
+ description: The SPI flash controller containing the flash to be exposed over the LPC to AHB mapping
+
+ required:
+ - compatible
+ - clocks
+
+ "^reset-controller@[0-9a-f]+$":
+ type: object
+
+ description:
+ The UARTs present in the ASPEED SoC can have their resets tied to the reset
+ state of the LPC bus. Some systems may chose to modify this configuration
+
+ properties:
+ comptabile:
+ items:
+ - enum:
+ - aspeed,ast2400-lpc-reset
+ - aspeed,ast2500-lpc-reset
+ - aspeed,ast2600-lpc-reset
+
+ reg:
+ maxItems: 1
+
+ required:
+ - compatible
+
+ "^lpc-snoop@[0-9a-f]+$":
+ type: object
+
+ description:
+ The LPC snoop interface allows the BMC to listen on and record the data
+ bytes written by the Host to the targeted LPC I/O pots.
+
+ properties:
+ comptabile:
+ items:
+ - enum:
+ - aspeed,ast2400-lpc-snoop
+ - aspeed,ast2500-lpc-snoop
+ - aspeed,ast2600-lpc-snoop
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ maxItems: 1
+
+ snoop-ports:
+ $ref: /schemas/types.yaml#/definitions/uint32-array
+ description: The LPC I/O ports to snoop
+
+ required:
+ - compatible
+ - interrupts
+ - snoop-ports
+
+required:
+ - compatible
+ - reg
+ - "#address-cells"
+ - "#size-cells"
+ - ranges
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/arm-gic.h>
+ #include <dt-bindings/clock/ast2600-clock.h>
+
+ lpc: lpc@1e789000 {
+ compatible = "aspeed,ast2600-lpc-v2", "simple-mfd", "syscon";
+ reg = <0x1e789000 0x1000>;
+
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges = <0x0 0x1e789000 0x1000>;
+
+ lpc_ctrl: lpc-ctrl@80 {
+ compatible = "aspeed,ast2600-lpc-ctrl";
+ reg = <0x80 0x80>;
+ clocks = <&syscon ASPEED_CLK_GATE_LCLK>;
+ memory-region = <&flash_memory>;
+ flash = <&spi>;
+ };
+
+ lpc_reset: reset-controller@98 {
+ compatible = "aspeed,ast2600-lpc-reset";
+ reg = <0x98 0x4>;
+ #reset-cells = <1>;
+ };
+
+ lpc_snoop: lpc-snoop@80 {
+ compatible = "aspeed,ast2600-lpc-snoop";
+ reg = <0x80 0x80>;
+ interrupts = <GIC_SPI 144 IRQ_TYPE_LEVEL_HIGH>;
+ snoop-ports = <0x80>;
+ };
+ };
--
2.17.1