Merging upstream version 6.9.2.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

3 files changed, 359 insertions, 480 deletions

diff --git a/Documentation/devicetree/bindings/fpga/fpga-region.txt b/Documentation/devicetree/bindings/fpga/fpga-region.txt
deleted file mode 100644
index 528df8a0e6..0000000000
--- a/Documentation/devicetree/bindings/fpga/fpga-region.txt
+++ /dev/null
@@ -1,479 +0,0 @@
-FPGA Region Device Tree Binding
-
-Alan Tull 2016
-
- CONTENTS
- - Introduction
- - Terminology
- - Sequence
- - FPGA Region
- - Supported Use Models
- - Device Tree Examples
- - Constraints
-
-
-Introduction
-============
-
-FPGA Regions represent FPGA's and partial reconfiguration regions of FPGA's in
-the Device Tree.  FPGA Regions provide a way to program FPGAs under device tree
-control.
-
-This device tree binding document hits some of the high points of FPGA usage and
-attempts to include terminology used by both major FPGA manufacturers.  This
-document isn't a replacement for any manufacturers specifications for FPGA
-usage.
-
-
-Terminology
-===========
-
-Full Reconfiguration
- * The entire FPGA is programmed.
-
-Partial Reconfiguration (PR)
- * A section of an FPGA is reprogrammed while the rest of the FPGA is not
-   affected.
- * Not all FPGA's support PR.
-
-Partial Reconfiguration Region (PRR)
- * Also called a "reconfigurable partition"
- * A PRR is a specific section of an FPGA reserved for reconfiguration.
- * A base (or static) FPGA image may create a set of PRR's that later may
-   be independently reprogrammed many times.
- * The size and specific location of each PRR is fixed.
- * The connections at the edge of each PRR are fixed.  The image that is loaded
-   into a PRR must fit and must use a subset of the region's connections.
- * The busses within the FPGA are split such that each region gets its own
-   branch that may be gated independently.
-
-Persona
- * Also called a "partial bit stream"
- * An FPGA image that is designed to be loaded into a PRR.  There may be
-   any number of personas designed to fit into a PRR, but only one at at time
-   may be loaded.
- * A persona may create more regions.
-
-FPGA Bridge
- * FPGA Bridges gate bus signals between a host and FPGA.
- * FPGA Bridges should be disabled while the FPGA is being programmed to
-   prevent spurious signals on the cpu bus and to the soft logic.
- * FPGA bridges may be actual hardware or soft logic on an FPGA.
- * During Full Reconfiguration, hardware bridges between the host and FPGA
-   will be disabled.
- * During Partial Reconfiguration of a specific region, that region's bridge
-   will be used to gate the busses.  Traffic to other regions is not affected.
- * In some implementations, the FPGA Manager transparently handles gating the
-   buses, eliminating the need to show the hardware FPGA bridges in the
-   device tree.
- * An FPGA image may create a set of reprogrammable regions, each having its
-   own bridge and its own split of the busses in the FPGA.
-
-FPGA Manager
- * An FPGA Manager is a hardware block that programs an FPGA under the control
-   of a host processor.
-
-Base Image
- * Also called the "static image"
- * An FPGA image that is designed to do full reconfiguration of the FPGA.
- * A base image may set up a set of partial reconfiguration regions that may
-   later be reprogrammed.
-
-    ----------------       ----------------------------------
-    |  Host CPU    |       |             FPGA               |
-    |              |       |                                |
-    |          ----|       |       -----------    --------  |
-    |          | H |       |   |==>| Bridge0 |<==>| PRR0 |  |
-    |          | W |       |   |   -----------    --------  |
-    |          |   |       |   |                            |
-    |          | B |<=====>|<==|   -----------    --------  |
-    |          | R |       |   |==>| Bridge1 |<==>| PRR1 |  |
-    |          | I |       |   |   -----------    --------  |
-    |          | D |       |   |                            |
-    |          | G |       |   |   -----------    --------  |
-    |          | E |       |   |==>| Bridge2 |<==>| PRR2 |  |
-    |          ----|       |       -----------    --------  |
-    |              |       |                                |
-    ----------------       ----------------------------------
-
-Figure 1: An FPGA set up with a base image that created three regions.  Each
-region (PRR0-2) gets its own split of the busses that is independently gated by
-a soft logic bridge (Bridge0-2) in the FPGA.  The contents of each PRR can be
-reprogrammed independently while the rest of the system continues to function.
-
-
-Sequence
-========
-
-When a DT overlay that targets an FPGA Region is applied, the FPGA Region will
-do the following:
-
- 1. Disable appropriate FPGA bridges.
- 2. Program the FPGA using the FPGA manager.
- 3. Enable the FPGA bridges.
- 4. The Device Tree overlay is accepted into the live tree.
- 5. Child devices are populated.
-
-When the overlay is removed, the child nodes will be removed and the FPGA Region
-will disable the bridges.
-
-
-FPGA Region
-===========
-
-FPGA Regions represent FPGA's and FPGA PR regions in the device tree.  An FPGA
-Region brings together the elements needed to program on a running system and
-add the child devices:
-
- * FPGA Manager
- * FPGA Bridges
- * image-specific information needed to to the programming.
- * child nodes
-
-The intended use is that a Device Tree overlay (DTO) can be used to reprogram an
-FPGA while an operating system is running.
-
-An FPGA Region that exists in the live Device Tree reflects the current state.
-If the live tree shows a "firmware-name" property or child nodes under an FPGA
-Region, the FPGA already has been programmed.  A DTO that targets an FPGA Region
-and adds the "firmware-name" property is taken as a request to reprogram the
-FPGA.  After reprogramming is successful, the overlay is accepted into the live
-tree.
-
-The base FPGA Region in the device tree represents the FPGA and supports full
-reconfiguration.  It must include a phandle to an FPGA Manager.  The base
-FPGA region will be the child of one of the hardware bridges (the bridge that
-allows register access) between the cpu and the FPGA.  If there are more than
-one bridge to control during FPGA programming, the region will also contain a
-list of phandles to the additional hardware FPGA Bridges.
-
-For partial reconfiguration (PR), each PR region will have an FPGA Region.
-These FPGA regions are children of FPGA bridges which are then children of the
-base FPGA region.  The "Full Reconfiguration to add PRR's" example below shows
-this.
-
-If an FPGA Region does not specify an FPGA Manager, it will inherit the FPGA
-Manager specified by its ancestor FPGA Region.  This supports both the case
-where the same FPGA Manager is used for all of an FPGA as well the case where
-a different FPGA Manager is used for each region.
-
-FPGA Regions do not inherit their ancestor FPGA regions' bridges.  This prevents
-shutting down bridges that are upstream from the other active regions while one
-region is getting reconfigured (see Figure 1 above).  During PR, the FPGA's
-hardware bridges remain enabled.  The PR regions' bridges will be FPGA bridges
-within the static image of the FPGA.
-
-Required properties:
-- compatible : should contain "fpga-region"
-- fpga-mgr : should contain a phandle to an FPGA Manager.  Child FPGA Regions
-	inherit this property from their ancestor regions.  An fpga-mgr property
-	in a region will override any inherited FPGA manager.
-- #address-cells, #size-cells, ranges : must be present to handle address space
-	mapping for child nodes.
-
-Optional properties:
-- firmware-name : should contain the name of an FPGA image file located on the
-	firmware search path.  If this property shows up in a live device tree
-	it indicates that the FPGA has already been programmed with this image.
-	If this property is in an overlay targeting an FPGA region, it is a
-	request to program the FPGA with that image.
-- fpga-bridges : should contain a list of phandles to FPGA Bridges that must be
-	controlled during FPGA programming along with the parent FPGA bridge.
-	This property is optional if the FPGA Manager handles the bridges.
-        If the fpga-region is  the child of an fpga-bridge, the list should not
-        contain the parent bridge.
-- partial-fpga-config : boolean, set if partial reconfiguration is to be done,
-	otherwise full reconfiguration is done.
-- external-fpga-config : boolean, set if the FPGA has already been configured
-	prior to OS boot up.
-- encrypted-fpga-config : boolean, set if the bitstream is encrypted
-- region-unfreeze-timeout-us : The maximum time in microseconds to wait for
-	bridges to successfully become enabled after the region has been
-	programmed.
-- region-freeze-timeout-us : The maximum time in microseconds to wait for
-	bridges to successfully become disabled before the region has been
-	programmed.
-- config-complete-timeout-us : The maximum time in microseconds time for the
-	FPGA to go to operating mode after the region has been programmed.
-- child nodes : devices in the FPGA after programming.
-
-In the example below, when an overlay is applied targeting fpga-region0,
-fpga_mgr is used to program the FPGA.  Two bridges are controlled during
-programming: the parent fpga_bridge0 and fpga_bridge1.  Because the region is
-the child of fpga_bridge0, only fpga_bridge1 needs to be specified in the
-fpga-bridges property.  During programming, these bridges are disabled, the
-firmware specified in the overlay is loaded to the FPGA using the FPGA manager
-specified in the region.  If FPGA programming succeeds, the bridges are
-reenabled and the overlay makes it into the live device tree.  The child devices
-are then populated.  If FPGA programming fails, the bridges are left disabled
-and the overlay is rejected.  The overlay's ranges property maps the lwhps
-bridge's region (0xff200000) and the hps bridge's region (0xc0000000) for use by
-the two child devices.
-
-Example:
-Base tree contains:
-
-	fpga_mgr: fpga-mgr@ff706000 {
-		compatible = "altr,socfpga-fpga-mgr";
-		reg = <0xff706000 0x1000
-		       0xffb90000 0x20>;
-		interrupts = <0 175 4>;
-	};
-
-	fpga_bridge0: fpga-bridge@ff400000 {
-		compatible = "altr,socfpga-lwhps2fpga-bridge";
-		reg = <0xff400000 0x100000>;
-		resets = <&rst LWHPS2FPGA_RESET>;
-		clocks = <&l4_main_clk>;
-
-		#address-cells = <1>;
-		#size-cells = <1>;
-		ranges;
-
-		fpga_region0: fpga-region0 {
-			compatible = "fpga-region";
-			fpga-mgr = <&fpga_mgr>;
-		};
-	};
-
-	fpga_bridge1: fpga-bridge@ff500000 {
-		compatible = "altr,socfpga-hps2fpga-bridge";
-		reg = <0xff500000 0x10000>;
-		resets = <&rst HPS2FPGA_RESET>;
-		clocks = <&l4_main_clk>;
-	};
-
-Overlay contains:
-
-/dts-v1/;
-/plugin/;
-
-&fpga_region0 {
-	#address-cells = <1>;
-	#size-cells = <1>;
-
-	firmware-name = "soc_system.rbf";
-	fpga-bridges = <&fpga_bridge1>;
-	ranges = <0x20000 0xff200000 0x100000>,
-		 <0x0 0xc0000000 0x20000000>;
-
-	gpio@10040 {
-		compatible = "altr,pio-1.0";
-		reg = <0x10040 0x20>;
-		altr,ngpio = <4>;
-		#gpio-cells = <2>;
-		clocks = <2>;
-		gpio-controller;
-	};
-
-	onchip-memory {
-		device_type = "memory";
-		compatible = "altr,onchipmem-15.1";
-		reg = <0x0 0x10000>;
-	};
-};
-
-
-Supported Use Models
-====================
-
-In all cases the live DT must have the FPGA Manager, FPGA Bridges (if any), and
-a FPGA Region.  The target of the Device Tree Overlay is the FPGA Region.  Some
-uses are specific to an FPGA device.
-
- * No FPGA Bridges
-   In this case, the FPGA Manager which programs the FPGA also handles the
-   bridges behind the scenes.  No FPGA Bridge devices are needed for full
-   reconfiguration.
-
- * Full reconfiguration with hardware bridges
-   In this case, there are hardware bridges between the processor and FPGA that
-   need to be controlled during full reconfiguration.  Before the overlay is
-   applied, the live DT must include the FPGA Manager, FPGA Bridges, and a
-   FPGA Region.  The FPGA Region is the child of the bridge that allows
-   register access to the FPGA.  Additional bridges may be listed in a
-   fpga-bridges property in the FPGA region or in the device tree overlay.
-
- * Partial reconfiguration with bridges in the FPGA
-   In this case, the FPGA will have one or more PRR's that may be programmed
-   separately while the rest of the FPGA can remain active.  To manage this,
-   bridges need to exist in the FPGA that can gate the buses going to each FPGA
-   region while the buses are enabled for other sections.  Before any partial
-   reconfiguration can be done, a base FPGA image must be loaded which includes
-   PRR's with FPGA bridges.  The device tree should have an FPGA region for each
-   PRR.
-
-Device Tree Examples
-====================
-
-The intention of this section is to give some simple examples, focusing on
-the placement of the elements detailed above, especially:
- * FPGA Manager
- * FPGA Bridges
- * FPGA Region
- * ranges
- * target-path or target
-
-For the purposes of this section, I'm dividing the Device Tree into two parts,
-each with its own requirements.  The two parts are:
- * The live DT prior to the overlay being added
- * The DT overlay
-
-The live Device Tree must contain an FPGA Region, an FPGA Manager, and any FPGA
-Bridges.  The FPGA Region's "fpga-mgr" property specifies the manager by phandle
-to handle programming the FPGA.  If the FPGA Region is the child of another FPGA
-Region, the parent's FPGA Manager is used.  If FPGA Bridges need to be involved,
-they are specified in the FPGA Region by the "fpga-bridges" property.  During
-FPGA programming, the FPGA Region will disable the bridges that are in its
-"fpga-bridges" list and will re-enable them after FPGA programming has
-succeeded.
-
-The Device Tree Overlay will contain:
- * "target-path" or "target"
-   The insertion point where the contents of the overlay will go into the
-   live tree.  target-path is a full path, while target is a phandle.
- * "ranges"
-    The address space mapping from processor to FPGA bus(ses).
- * "firmware-name"
-   Specifies the name of the FPGA image file on the firmware search
-   path.  The search path is described in the firmware class documentation.
- * "partial-fpga-config"
-   This binding is a boolean and should be present if partial reconfiguration
-   is to be done.
- * child nodes corresponding to hardware that will be loaded in this region of
-   the FPGA.
-
-Device Tree Example: Full Reconfiguration without Bridges
-=========================================================
-
-Live Device Tree contains:
-	fpga_mgr0: fpga-mgr@f8007000 {
-		compatible = "xlnx,zynq-devcfg-1.0";
-		reg = <0xf8007000 0x100>;
-		interrupt-parent = <&intc>;
-		interrupts = <0 8 4>;
-		clocks = <&clkc 12>;
-		clock-names = "ref_clk";
-		syscon = <&slcr>;
-	};
-
-	fpga_region0: fpga-region0 {
-		compatible = "fpga-region";
-		fpga-mgr = <&fpga_mgr0>;
-		#address-cells = <0x1>;
-		#size-cells = <0x1>;
-		ranges;
-	};
-
-DT Overlay contains:
-
-/dts-v1/;
-/plugin/;
-
-&fpga_region0 {
-	#address-cells = <1>;
-	#size-cells = <1>;
-
-	firmware-name = "zynq-gpio.bin";
-
-	gpio1: gpio@40000000 {
-		compatible = "xlnx,xps-gpio-1.00.a";
-		reg = <0x40000000 0x10000>;
-		gpio-controller;
-		#gpio-cells = <0x2>;
-		xlnx,gpio-width= <0x6>;
-	};
-};
-
-Device Tree Example: Full Reconfiguration to add PRR's
-======================================================
-
-The base FPGA Region is specified similar to the first example above.
-
-This example programs the FPGA to have two regions that can later be partially
-configured.  Each region has its own bridge in the FPGA fabric.
-
-DT Overlay contains:
-
-/dts-v1/;
-/plugin/;
-
-&fpga_region0 {
-	#address-cells = <1>;
-	#size-cells = <1>;
-
-	firmware-name = "base.rbf";
-
-	fpga-bridge@4400 {
-		compatible = "altr,freeze-bridge-controller";
-		reg = <0x4400 0x10>;
-
-		fpga_region1: fpga-region1 {
-			compatible = "fpga-region";
-			#address-cells = <0x1>;
-			#size-cells = <0x1>;
-			ranges;
-		};
-	};
-
-	fpga-bridge@4420 {
-		compatible = "altr,freeze-bridge-controller";
-		reg = <0x4420 0x10>;
-
-		fpga_region2: fpga-region2 {
-			compatible = "fpga-region";
-			#address-cells = <0x1>;
-			#size-cells = <0x1>;
-			ranges;
-		};
-	};
-};
-
-Device Tree Example: Partial Reconfiguration
-============================================
-
-This example reprograms one of the PRR's set up in the previous example.
-
-The sequence that occurs when this overlay is similar to the above, the only
-differences are that the FPGA is partially reconfigured due to the
-"partial-fpga-config" boolean and the only bridge that is controlled during
-programming is the FPGA based bridge of fpga_region1.
-
-/dts-v1/;
-/plugin/;
-
-&fpga_region1 {
-	#address-cells = <1>;
-	#size-cells = <1>;
-
-	firmware-name = "soc_image2.rbf";
-	partial-fpga-config;
-
-	gpio@10040 {
-		compatible = "altr,pio-1.0";
-		reg = <0x10040 0x20>;
-		clocks = <0x2>;
-		altr,ngpio = <0x4>;
-		#gpio-cells = <0x2>;
-		gpio-controller;
-	};
-};
-
-Constraints
-===========
-
-It is beyond the scope of this document to fully describe all the FPGA design
-constraints required to make partial reconfiguration work[1] [2] [3], but a few
-deserve quick mention.
-
-A persona must have boundary connections that line up with those of the partition
-or region it is designed to go into.
-
-During programming, transactions through those connections must be stopped and
-the connections must be held at a fixed logic level.  This can be achieved by
-FPGA Bridges that exist on the FPGA fabric prior to the partial reconfiguration.
-
---
-[1] www.altera.com/content/dam/altera-www/global/en_US/pdfs/literature/ug/ug_partrecon.pdf
-[2] tspace.library.utoronto.ca/bitstream/1807/67932/1/Byma_Stuart_A_201411_MAS_thesis.pdf
-[3] https://www.xilinx.com/support/documentation/sw_manuals/xilinx14_1/ug702.pdf
diff --git a/Documentation/devicetree/bindings/fpga/fpga-region.yaml b/Documentation/devicetree/bindings/fpga/fpga-region.yaml
new file mode 100644
index 0000000000..77554885a6
--- /dev/null
+++ b/Documentation/devicetree/bindings/fpga/fpga-region.yaml
@@ -0,0 +1,358 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/fpga/fpga-region.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: FPGA Region
+
+maintainers:
+  - Michal Simek <michal.simek@amd.com>
+
+description: |
+  CONTENTS
+   - Introduction
+   - Terminology
+   - Sequence
+   - FPGA Region
+   - Supported Use Models
+   - Constraints
+
+
+  Introduction
+  ============
+
+  FPGA Regions represent FPGA's and partial reconfiguration regions of FPGA's in
+  the Device Tree.  FPGA Regions provide a way to program FPGAs under device tree
+  control.
+
+  The documentation hits some of the high points of FPGA usage and
+  attempts to include terminology used by both major FPGA manufacturers.  This
+  document isn't a replacement for any manufacturers specifications for FPGA
+  usage.
+
+
+  Terminology
+  ===========
+
+  Full Reconfiguration
+   * The entire FPGA is programmed.
+
+  Partial Reconfiguration (PR)
+   * A section of an FPGA is reprogrammed while the rest of the FPGA is not
+     affected.
+   * Not all FPGA's support PR.
+
+  Partial Reconfiguration Region (PRR)
+   * Also called a "reconfigurable partition"
+   * A PRR is a specific section of an FPGA reserved for reconfiguration.
+   * A base (or static) FPGA image may create a set of PRR's that later may
+     be independently reprogrammed many times.
+   * The size and specific location of each PRR is fixed.
+   * The connections at the edge of each PRR are fixed.  The image that is loaded
+     into a PRR must fit and must use a subset of the region's connections.
+   * The busses within the FPGA are split such that each region gets its own
+     branch that may be gated independently.
+
+  Persona
+   * Also called a "partial bit stream"
+   * An FPGA image that is designed to be loaded into a PRR.  There may be
+     any number of personas designed to fit into a PRR, but only one at a time
+     may be loaded.
+   * A persona may create more regions.
+
+  FPGA Bridge
+   * FPGA Bridges gate bus signals between a host and FPGA.
+   * FPGA Bridges should be disabled while the FPGA is being programmed to
+     prevent spurious signals on the cpu bus and to the soft logic.
+   * FPGA bridges may be actual hardware or soft logic on an FPGA.
+   * During Full Reconfiguration, hardware bridges between the host and FPGA
+     will be disabled.
+   * During Partial Reconfiguration of a specific region, that region's bridge
+     will be used to gate the busses.  Traffic to other regions is not affected.
+   * In some implementations, the FPGA Manager transparently handles gating the
+     buses, eliminating the need to show the hardware FPGA bridges in the
+     device tree.
+   * An FPGA image may create a set of reprogrammable regions, each having its
+     own bridge and its own split of the busses in the FPGA.
+
+  FPGA Manager
+   * An FPGA Manager is a hardware block that programs an FPGA under the control
+     of a host processor.
+
+  Base Image
+   * Also called the "static image"
+   * An FPGA image that is designed to do full reconfiguration of the FPGA.
+   * A base image may set up a set of partial reconfiguration regions that may
+     later be reprogrammed.
+
+      ----------------       ----------------------------------
+      |  Host CPU    |       |             FPGA               |
+      |              |       |                                |
+      |          ----|       |       -----------    --------  |
+      |          | H |       |   |==>| Bridge0 |<==>| PRR0 |  |
+      |          | W |       |   |   -----------    --------  |
+      |          |   |       |   |                            |
+      |          | B |<=====>|<==|   -----------    --------  |
+      |          | R |       |   |==>| Bridge1 |<==>| PRR1 |  |
+      |          | I |       |   |   -----------    --------  |
+      |          | D |       |   |                            |
+      |          | G |       |   |   -----------    --------  |
+      |          | E |       |   |==>| Bridge2 |<==>| PRR2 |  |
+      |          ----|       |       -----------    --------  |
+      |              |       |                                |
+      ----------------       ----------------------------------
+
+  Figure 1: An FPGA set up with a base image that created three regions.  Each
+  region (PRR0-2) gets its own split of the busses that is independently gated by
+  a soft logic bridge (Bridge0-2) in the FPGA.  The contents of each PRR can be
+  reprogrammed independently while the rest of the system continues to function.
+
+
+  Sequence
+  ========
+
+  When a DT overlay that targets an FPGA Region is applied, the FPGA Region will
+  do the following:
+
+   1. Disable appropriate FPGA bridges.
+   2. Program the FPGA using the FPGA manager.
+   3. Enable the FPGA bridges.
+   4. The Device Tree overlay is accepted into the live tree.
+   5. Child devices are populated.
+
+  When the overlay is removed, the child nodes will be removed and the FPGA Region
+  will disable the bridges.
+
+
+  FPGA Region
+  ===========
+
+  FPGA Regions represent FPGA's and FPGA PR regions in the device tree.  An FPGA
+  Region brings together the elements needed to program on a running system and
+  add the child devices:
+
+   * FPGA Manager
+   * FPGA Bridges
+   * image-specific information needed to the programming.
+   * child nodes
+
+  The intended use is that a Device Tree overlay (DTO) can be used to reprogram an
+  FPGA while an operating system is running.
+
+  An FPGA Region that exists in the live Device Tree reflects the current state.
+  If the live tree shows a "firmware-name" property or child nodes under an FPGA
+  Region, the FPGA already has been programmed.  A DTO that targets an FPGA Region
+  and adds the "firmware-name" property is taken as a request to reprogram the
+  FPGA.  After reprogramming is successful, the overlay is accepted into the live
+  tree.
+
+  The base FPGA Region in the device tree represents the FPGA and supports full
+  reconfiguration.  It must include a phandle to an FPGA Manager.  The base
+  FPGA region will be the child of one of the hardware bridges (the bridge that
+  allows register access) between the cpu and the FPGA.  If there are more than
+  one bridge to control during FPGA programming, the region will also contain a
+  list of phandles to the additional hardware FPGA Bridges.
+
+  For partial reconfiguration (PR), each PR region will have an FPGA Region.
+  These FPGA regions are children of FPGA bridges which are then children of the
+  base FPGA region.  The "Full Reconfiguration to add PRR's" example below shows
+  this.
+
+  If an FPGA Region does not specify an FPGA Manager, it will inherit the FPGA
+  Manager specified by its ancestor FPGA Region.  This supports both the case
+  where the same FPGA Manager is used for all of an FPGA as well the case where
+  a different FPGA Manager is used for each region.
+
+  FPGA Regions do not inherit their ancestor FPGA regions' bridges.  This prevents
+  shutting down bridges that are upstream from the other active regions while one
+  region is getting reconfigured (see Figure 1 above).  During PR, the FPGA's
+  hardware bridges remain enabled.  The PR regions' bridges will be FPGA bridges
+  within the static image of the FPGA.
+
+
+  Supported Use Models
+  ====================
+
+  In all cases the live DT must have the FPGA Manager, FPGA Bridges (if any), and
+  a FPGA Region.  The target of the Device Tree Overlay is the FPGA Region.  Some
+  uses are specific to an FPGA device.
+
+   * No FPGA Bridges
+     In this case, the FPGA Manager which programs the FPGA also handles the
+     bridges behind the scenes.  No FPGA Bridge devices are needed for full
+     reconfiguration.
+
+   * Full reconfiguration with hardware bridges
+     In this case, there are hardware bridges between the processor and FPGA that
+     need to be controlled during full reconfiguration.  Before the overlay is
+     applied, the live DT must include the FPGA Manager, FPGA Bridges, and a
+     FPGA Region.  The FPGA Region is the child of the bridge that allows
+     register access to the FPGA.  Additional bridges may be listed in a
+     fpga-bridges property in the FPGA region or in the device tree overlay.
+
+   * Partial reconfiguration with bridges in the FPGA
+     In this case, the FPGA will have one or more PRR's that may be programmed
+     separately while the rest of the FPGA can remain active.  To manage this,
+     bridges need to exist in the FPGA that can gate the buses going to each FPGA
+     region while the buses are enabled for other sections.  Before any partial
+     reconfiguration can be done, a base FPGA image must be loaded which includes
+     PRR's with FPGA bridges.  The device tree should have an FPGA region for each
+     PRR.
+
+  Constraints
+  ===========
+
+  It is beyond the scope of this document to fully describe all the FPGA design
+  constraints required to make partial reconfiguration work[1] [2] [3], but a few
+  deserve quick mention.
+
+  A persona must have boundary connections that line up with those of the partition
+  or region it is designed to go into.
+
+  During programming, transactions through those connections must be stopped and
+  the connections must be held at a fixed logic level.  This can be achieved by
+  FPGA Bridges that exist on the FPGA fabric prior to the partial reconfiguration.
+
+  --
+  [1] www.altera.com/content/dam/altera-www/global/en_US/pdfs/literature/ug/ug_partrecon.pdf
+  [2] tspace.library.utoronto.ca/bitstream/1807/67932/1/Byma_Stuart_A_201411_MAS_thesis.pdf
+  [3] https://www.xilinx.com/support/documentation/sw_manuals/xilinx14_1/ug702.pdf
+
+properties:
+  $nodename:
+    pattern: "^fpga-region(@.*|-([0-9]|[1-9][0-9]+))?$"
+
+  compatible:
+    const: fpga-region
+
+  reg:
+    maxItems: 1
+
+  ranges: true
+  "#address-cells": true
+  "#size-cells": true
+
+  config-complete-timeout-us:
+    description:
+      The maximum time in microseconds time for the FPGA to go to operating
+      mode after the region has been programmed.
+
+  encrypted-fpga-config:
+    type: boolean
+    description:
+      Set if the bitstream is encrypted.
+
+  external-fpga-config:
+    type: boolean
+    description:
+      Set if the FPGA has already been configured prior to OS boot up.
+
+  firmware-name:
+    maxItems: 1
+    description:
+      Should contain the name of an FPGA image file located on the firmware
+      search path. If this property shows up in a live device tree it indicates
+      that the FPGA has already been programmed with this image.
+      If this property is in an overlay targeting an FPGA region, it is
+      a request to program the FPGA with that image.
+
+  fpga-bridges:
+    $ref: /schemas/types.yaml#/definitions/phandle-array
+    description:
+      Should contain a list of phandles to FPGA Bridges that must be
+      controlled during FPGA programming along with the parent FPGA bridge.
+      This property is optional if the FPGA Manager handles the bridges.
+      If the fpga-region is  the child of an fpga-bridge, the list should not
+      contain the parent bridge.
+
+  fpga-mgr:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description:
+      Should contain a phandle to an FPGA Manager.  Child FPGA Regions
+      inherit this property from their ancestor regions.  An fpga-mgr property
+      in a region will override any inherited FPGA manager.
+
+  partial-fpga-config:
+    type: boolean
+    description:
+      Set if partial reconfiguration is to be done, otherwise full
+      reconfiguration is done.
+
+  region-freeze-timeout-us:
+    description:
+      The maximum time in microseconds to wait for bridges to successfully
+      become disabled before the region has been programmed.
+
+  region-unfreeze-timeout-us:
+    description:
+      The maximum time in microseconds to wait for bridges to successfully
+      become enabled after the region has been programmed.
+
+required:
+  - compatible
+  - fpga-mgr
+
+additionalProperties:
+  type: object
+
+examples:
+  - |
+    /*
+     * Full Reconfiguration without Bridges with DT overlay
+     */
+    fpga_region0: fpga-region@0 {
+      compatible = "fpga-region";
+      reg = <0 0>;
+      #address-cells = <1>;
+      #size-cells = <1>;
+      fpga-mgr = <&fpga_mgr0>;
+      ranges = <0x10000000 0x20000000 0x10000000>;
+
+      /* DT Overlay contains: &fpga_region0 */
+      firmware-name = "zynq-gpio.bin";
+      gpio@40000000 {
+        compatible = "xlnx,xps-gpio-1.00.a";
+        reg = <0x40000000 0x10000>;
+        gpio-controller;
+        #gpio-cells = <2>;
+      };
+    };
+
+  - |
+    /*
+     * Partial reconfiguration with bridge
+     */
+    fpga_region1: fpga-region@0 {
+      compatible = "fpga-region";
+      reg = <0 0>;
+      ranges;
+      #address-cells = <1>;
+      #size-cells = <1>;
+      fpga-mgr = <&fpga_mgr1>;
+      fpga-bridges = <&fpga_bridge1>;
+      partial-fpga-config;
+
+      /* DT Overlay contains: &fpga_region1 */
+      firmware-name = "zynq-gpio-partial.bin";
+      clk: clock {
+        compatible = "fixed-factor-clock";
+        clocks = <&parentclk>;
+        #clock-cells = <0>;
+        clock-div = <2>;
+        clock-mult = <1>;
+      };
+      axi {
+        compatible = "simple-bus";
+        #address-cells = <1>;
+        #size-cells = <1>;
+        ranges;
+        gpio@40000000 {
+          compatible = "xlnx,xps-gpio-1.00.a";
+          reg = <0x40000000 0x10000>;
+          #gpio-cells = <2>;
+          gpio-controller;
+          clocks = <&clk>;
+        };
+      };
+    };
diff --git a/Documentation/devicetree/bindings/fpga/xlnx,versal-fpga.yaml b/Documentation/devicetree/bindings/fpga/xlnx,versal-fpga.yaml
index 26f18834ca..80833462f6 100644
--- a/Documentation/devicetree/bindings/fpga/xlnx,versal-fpga.yaml
+++ b/Documentation/devicetree/bindings/fpga/xlnx,versal-fpga.yaml
@@ -26,7 +26,7 @@ additionalProperties: false
 
 examples:
   - |
-    versal_fpga: versal_fpga {
+    versal_fpga: versal-fpga {
          compatible = "xlnx,versal-fpga";
     };