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-rw-r--r--Documentation/devicetree/bindings/fsi/fsi-master-aspeed.txt36
-rw-r--r--Documentation/devicetree/bindings/fsi/fsi-master-ast-cf.txt36
-rw-r--r--Documentation/devicetree/bindings/fsi/fsi-master-gpio.txt28
-rw-r--r--Documentation/devicetree/bindings/fsi/fsi.txt156
-rw-r--r--Documentation/devicetree/bindings/fsi/ibm,fsi2spi.yaml39
-rw-r--r--Documentation/devicetree/bindings/fsi/ibm,p9-occ.txt16
6 files changed, 311 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/fsi/fsi-master-aspeed.txt b/Documentation/devicetree/bindings/fsi/fsi-master-aspeed.txt
new file mode 100644
index 000000000..9853fefff
--- /dev/null
+++ b/Documentation/devicetree/bindings/fsi/fsi-master-aspeed.txt
@@ -0,0 +1,36 @@
+Device-tree bindings for AST2600 FSI master
+-------------------------------------------
+
+The AST2600 contains two identical FSI masters. They share a clock and have a
+separate interrupt line and output pins.
+
+Required properties:
+ - compatible: "aspeed,ast2600-fsi-master"
+ - reg: base address and length
+ - clocks: phandle and clock number
+ - interrupts: platform dependent interrupt description
+ - pinctrl-0: phandle to pinctrl node
+ - pinctrl-names: pinctrl state
+
+Optional properties:
+ - cfam-reset-gpios: GPIO for CFAM reset
+
+ - fsi-routing-gpios: GPIO for setting the FSI mux (internal or cabled)
+ - fsi-mux-gpios: GPIO for detecting the desired FSI mux state
+
+
+Examples:
+
+ fsi-master {
+ compatible = "aspeed,ast2600-fsi-master", "fsi-master";
+ reg = <0x1e79b000 0x94>;
+ interrupts = <GIC_SPI 100 IRQ_TYPE_LEVEL_HIGH>;
+ pinctrl-names = "default";
+ pinctrl-0 = <&pinctrl_fsi1_default>;
+ clocks = <&syscon ASPEED_CLK_GATE_FSICLK>;
+
+ fsi-routing-gpios = <&gpio0 ASPEED_GPIO(Q, 7) GPIO_ACTIVE_HIGH>;
+ fsi-mux-gpios = <&gpio0 ASPEED_GPIO(B, 0) GPIO_ACTIVE_HIGH>;
+
+ cfam-reset-gpios = <&gpio0 ASPEED_GPIO(Q, 0) GPIO_ACTIVE_LOW>;
+ };
diff --git a/Documentation/devicetree/bindings/fsi/fsi-master-ast-cf.txt b/Documentation/devicetree/bindings/fsi/fsi-master-ast-cf.txt
new file mode 100644
index 000000000..3dc752db7
--- /dev/null
+++ b/Documentation/devicetree/bindings/fsi/fsi-master-ast-cf.txt
@@ -0,0 +1,36 @@
+Device-tree bindings for ColdFire offloaded gpio-based FSI master driver
+------------------------------------------------------------------------
+
+Required properties:
+ - compatible =
+ "aspeed,ast2400-cf-fsi-master" for an AST2400 based system
+ or
+ "aspeed,ast2500-cf-fsi-master" for an AST2500 based system
+
+ - clock-gpios = <gpio-descriptor>; : GPIO for FSI clock
+ - data-gpios = <gpio-descriptor>; : GPIO for FSI data signal
+ - enable-gpios = <gpio-descriptor>; : GPIO for enable signal
+ - trans-gpios = <gpio-descriptor>; : GPIO for voltage translator enable
+ - mux-gpios = <gpio-descriptor>; : GPIO for pin multiplexing with other
+ functions (eg, external FSI masters)
+ - memory-region = <phandle>; : Reference to the reserved memory for
+ the ColdFire. Must be 2M aligned on
+ AST2400 and 1M aligned on AST2500
+ - aspeed,sram = <phandle>; : Reference to the SRAM node.
+ - aspeed,cvic = <phandle>; : Reference to the CVIC node.
+
+Examples:
+
+ fsi-master {
+ compatible = "aspeed,ast2500-cf-fsi-master", "fsi-master";
+
+ clock-gpios = <&gpio 0>;
+ data-gpios = <&gpio 1>;
+ enable-gpios = <&gpio 2>;
+ trans-gpios = <&gpio 3>;
+ mux-gpios = <&gpio 4>;
+
+ memory-region = <&coldfire_memory>;
+ aspeed,sram = <&sram>;
+ aspeed,cvic = <&cvic>;
+ }
diff --git a/Documentation/devicetree/bindings/fsi/fsi-master-gpio.txt b/Documentation/devicetree/bindings/fsi/fsi-master-gpio.txt
new file mode 100644
index 000000000..1e4424507
--- /dev/null
+++ b/Documentation/devicetree/bindings/fsi/fsi-master-gpio.txt
@@ -0,0 +1,28 @@
+Device-tree bindings for gpio-based FSI master driver
+-----------------------------------------------------
+
+Required properties:
+ - compatible = "fsi-master-gpio";
+ - clock-gpios = <gpio-descriptor>; : GPIO for FSI clock
+ - data-gpios = <gpio-descriptor>; : GPIO for FSI data signal
+
+Optional properties:
+ - enable-gpios = <gpio-descriptor>; : GPIO for enable signal
+ - trans-gpios = <gpio-descriptor>; : GPIO for voltage translator enable
+ - mux-gpios = <gpio-descriptor>; : GPIO for pin multiplexing with other
+ functions (eg, external FSI masters)
+ - no-gpio-delays; : Don't add extra delays between GPIO
+ accesses. This is useful when the HW
+ GPIO block is running at a low enough
+ frequency.
+
+Examples:
+
+ fsi-master {
+ compatible = "fsi-master-gpio", "fsi-master";
+ clock-gpios = <&gpio 0>;
+ data-gpios = <&gpio 1>;
+ enable-gpios = <&gpio 2>;
+ trans-gpios = <&gpio 3>;
+ mux-gpios = <&gpio 4>;
+ }
diff --git a/Documentation/devicetree/bindings/fsi/fsi.txt b/Documentation/devicetree/bindings/fsi/fsi.txt
new file mode 100644
index 000000000..afb4eccab
--- /dev/null
+++ b/Documentation/devicetree/bindings/fsi/fsi.txt
@@ -0,0 +1,156 @@
+FSI bus & engine generic device tree bindings
+=============================================
+
+The FSI bus is probe-able, so the OS is able to enumerate FSI slaves, and
+engines within those slaves. However, we have a facility to match devicetree
+nodes to probed engines. This allows for fsi engines to expose non-probeable
+busses, which are then exposed by the device tree. For example, an FSI engine
+that is an I2C master - the I2C bus can be described by the device tree under
+the engine's device tree node.
+
+FSI masters may require their own DT nodes (to describe the master HW itself);
+that requirement is defined by the master's implementation, and is described by
+the fsi-master-* binding specifications.
+
+Under the masters' nodes, we can describe the bus topology using nodes to
+represent the FSI slaves and their slave engines. As a basic outline:
+
+ fsi-master {
+ /* top-level of FSI bus topology, bound to an FSI master driver and
+ * exposes an FSI bus */
+
+ fsi-slave@<link,id> {
+ /* this node defines the FSI slave device, and is handled
+ * entirely with FSI core code */
+
+ fsi-slave-engine@<addr> {
+ /* this node defines the engine endpoint & address range, which
+ * is bound to the relevant fsi device driver */
+ ...
+ };
+
+ fsi-slave-engine@<addr> {
+ ...
+ };
+
+ };
+ };
+
+Note that since the bus is probe-able, some (or all) of the topology may
+not be described; this binding only provides an optional facility for
+adding subordinate device tree nodes as children of FSI engines.
+
+FSI masters
+-----------
+
+FSI master nodes declare themselves as such with the "fsi-master" compatible
+value. It's likely that an implementation-specific compatible value will
+be needed as well, for example:
+
+ compatible = "fsi-master-gpio", "fsi-master";
+
+Since the master nodes describe the top-level of the FSI topology, they also
+need to declare the FSI-standard addressing scheme. This requires two cells for
+addresses (link index and slave ID), and no size:
+
+ #address-cells = <2>;
+ #size-cells = <0>;
+
+An optional boolean property can be added to indicate that a particular master
+should not scan for connected devices at initialization time. This is
+necessary in cases where a scan could cause arbitration issues with other
+masters that may be present on the bus.
+
+ no-scan-on-init;
+
+FSI slaves
+----------
+
+Slaves are identified by a (link-index, slave-id) pair, so require two cells
+for an address identifier. Since these are not a range, no size cells are
+required. For an example, a slave on link 1, with ID 2, could be represented
+as:
+
+ cfam@1,2 {
+ reg = <1 2>;
+ [...];
+ }
+
+Each slave provides an address-space, under which the engines are accessible.
+That address space has a maximum of 23 bits, so we use one cell to represent
+addresses and sizes in the slave address space:
+
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+Optionally, a slave can provide a global unique chip ID which is used to
+identify the physical location of the chip in a system specific way
+
+ chip-id = <0>;
+
+FSI engines (devices)
+---------------------
+
+Engines are identified by their address under the slaves' address spaces. We
+use a single cell for address and size. Engine nodes represent the endpoint
+FSI device, and are passed to those FSI device drivers' ->probe() functions.
+
+For example, for a slave using a single 0x400-byte page starting at address
+0xc00:
+
+ engine@c00 {
+ reg = <0xc00 0x400>;
+ };
+
+
+Full example
+------------
+
+Here's an example that illustrates:
+ - an FSI master
+ - connected to an FSI slave
+ - that contains an engine that is an I2C master
+ - connected to an I2C EEPROM
+
+The FSI master may be connected to additional slaves, and slaves may have
+additional engines, but they don't necessarily need to be describe in the
+device tree if no extra platform information is required.
+
+ /* The GPIO-based FSI master node, describing the top level of the
+ * FSI bus
+ */
+ gpio-fsi {
+ compatible = "fsi-master-gpio", "fsi-master";
+ #address-cells = <2>;
+ #size-cells = <0>;
+
+ /* A FSI slave (aka. CFAM) at link 0, ID 0. */
+ cfam@0,0 {
+ reg = <0 0>;
+ #address-cells = <1>;
+ #size-cells = <1>;
+ chip-id = <0>;
+
+ /* FSI engine at 0xc00, using a single page. In this example,
+ * it's an I2C master controller, so subnodes describe the
+ * I2C bus.
+ */
+ i2c-controller@c00 {
+ reg = <0xc00 0x400>;
+
+ /* Engine-specific data. In this case, we're describing an
+ * I2C bus, so we're conforming to the generic I2C binding
+ */
+ compatible = "some-vendor,fsi-i2c-controller";
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ /* I2C endpoint device: an Atmel EEPROM */
+ eeprom@50 {
+ compatible = "atmel,24c256";
+ reg = <0x50>;
+ pagesize = <64>;
+ };
+ };
+ };
+ };
diff --git a/Documentation/devicetree/bindings/fsi/ibm,fsi2spi.yaml b/Documentation/devicetree/bindings/fsi/ibm,fsi2spi.yaml
new file mode 100644
index 000000000..e42527865
--- /dev/null
+++ b/Documentation/devicetree/bindings/fsi/ibm,fsi2spi.yaml
@@ -0,0 +1,39 @@
+# SPDX-License-Identifier: (GPL-2.0-or-later)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/fsi/ibm,fsi2spi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: IBM FSI-attached SPI controllers
+
+maintainers:
+ - Eddie James <eajames@linux.ibm.com>
+
+description: |
+ This binding describes an FSI CFAM engine called the FSI2SPI. Therefore this
+ node will always be a child of an FSI CFAM node; see fsi.txt for details on
+ FSI slave and CFAM nodes. This FSI2SPI engine provides access to a number of
+ SPI controllers.
+
+properties:
+ compatible:
+ enum:
+ - ibm,fsi2spi
+ - ibm,fsi2spi-restricted
+
+ reg:
+ items:
+ - description: FSI slave address
+
+required:
+ - compatible
+ - reg
+
+additionalProperties: false
+
+examples:
+ - |
+ fsi2spi@1c00 {
+ compatible = "ibm,fsi2spi";
+ reg = <0x1c00 0x400>;
+ };
diff --git a/Documentation/devicetree/bindings/fsi/ibm,p9-occ.txt b/Documentation/devicetree/bindings/fsi/ibm,p9-occ.txt
new file mode 100644
index 000000000..99ca9862a
--- /dev/null
+++ b/Documentation/devicetree/bindings/fsi/ibm,p9-occ.txt
@@ -0,0 +1,16 @@
+Device-tree bindings for FSI-attached POWER9 On-Chip Controller (OCC)
+---------------------------------------------------------------------
+
+This is the binding for the P9 On-Chip Controller accessed over FSI from a
+service processor. See fsi.txt for details on bindings for FSI slave and CFAM
+nodes. The OCC is not an FSI slave device itself, rather it is accessed
+through the SBE fifo.
+
+Required properties:
+ - compatible = "ibm,p9-occ"
+
+Examples:
+
+ occ {
+ compatible = "ibm,p9-occ";
+ };