[PATCH v3 00/16] Enable upper layers using FPGA region w/o device tree

[PATCH v3 00/16] Enable upper layers using FPGA region w/o device tree

[Alan Tull]

* Change the fpga-mgr API to have one fpga_mgr_load function
  instead of three.

* Expose API functions for FPGA region

* Separate common FPGA region code from Device Tree support

* Add API functions for bridges where DT is not used.

This is needed because the current FPGA layer has a couple of problems:

* We now have 3 functions for programming a FPGA, depending on whether
the image is in a sg list, a buffer, or firmware.  So upper layers
have to be written assuming where the image will be or will have to
write extra code to maintain flexibility.

* users who aren't using device tree are left to write their
own code that is essentially a rewrite of FPGA region.

Currently on the linux-fpga git repo as branch
next-20170615-fpga-region-api-v3

Patch 1 updates documentation and adds a FPGA region API doc.

Patch 2 adds non-dt support for fpga-bridges

Patch 3 changes the FPGA manager API, replacing the 3 FPGA load
functions with a single function that can handle whether the image
is a sg list, a contiguous buffer, or a firmware file.

Patch 4 separates getting a ref to a manager from locking it so
code can hang onto a ref without preventing other users from
using the manager to program a FPGA.

Patches 5 to 16 separate FPGA region common code from DT overlay
support and adds API functions.  Functional code changes are separated
into a bunch of little patches.  The last patch actually moves code to
of-fpga-region.c with only minor init/probe changes as this becomes
two modules.

I've tested this functionally for all patches separately.

Code changes from v3 are pretty small.

Changes in v3:
* rewrite fpga-region.txt
* fix bisect, test on each patch
* change fpga_region_program_fpga take only the region as a parameter
* update docs for fpga_region_program_fpga change

Changes in v2:
* split the final (large) patch into smaller patches for easier reviewability.
* documentation has been expanded
* reorder things, clean up
* dev_err instead of pr_err
* move functions that alloc/free image info from fpga-region.c to fpga-mgr.c
* move fpga-region.h to include/linux/fpga/
* add fpga_region_class_find to fpga-region.c
* move of_fpga_region_find to of-fpga-region.c

Alan Tull (16):
  doc: fpga: update documents for the FPGA API
  fpga: bridge: support getting bridge from device
  fpga: mgr: API change to replace fpga load functions with single
    function
  fpga: mgr: separate getting/locking FPGA manager
  fpga: region: use dev_err instead of pr_err
  fpga: region: remove unneeded of_node_get and put
  fpga: region: get mgr early on
  fpga: region: check for child regions before allocing image info
  fpga: region: fix slow warning with more than one overlay
  fpga: region: use image info as parameter for programming region
  fpga: region: separate out code that parses the overlay
  fpga: region: add fpga-region.h header
  fpga: region: rename some functions prior to moving
  fpga: region: add register/unregister functions
  fpga: region: add fpga_region_class_find
  fpga: region: move device tree support to of-fpga-region.c

 Documentation/fpga/fpga-mgr.txt    | 133 +++++-----
 Documentation/fpga/fpga-region.txt |  95 +++++++
 Documentation/fpga/overview.txt    |  23 ++
 drivers/fpga/Kconfig               |  13 +-
 drivers/fpga/Makefile              |   1 +
 drivers/fpga/fpga-bridge.c         | 110 +++++++--
 drivers/fpga/fpga-mgr.c            | 111 +++++++--
 drivers/fpga/fpga-region.c         | 463 ++++------------------------------
 drivers/fpga/of-fpga-region.c      | 495 +++++++++++++++++++++++++++++++++++++
 include/linux/fpga/fpga-bridge.h   |   7 +-
 include/linux/fpga/fpga-mgr.h      |  29 ++-
 include/linux/fpga/fpga-region.h   |  38 +++
 12 files changed, 975 insertions(+), 543 deletions(-)
 create mode 100644 Documentation/fpga/fpga-region.txt
 create mode 100644 Documentation/fpga/overview.txt
 create mode 100644 drivers/fpga/of-fpga-region.c
 create mode 100644 include/linux/fpga/fpga-region.h

-- 
2.7.4

[PATCH v3 01/16] doc: fpga: update documents for the FPGA API

[Alan Tull]

The FPGA manager has been simplified to have a single
fpga_mgr_load function which replaces the three
fpga_mgr_*load* functions.

The parameters presenting the FPGA image have been
added to struct fpga_image_info.

Additional functions have been added to alloc/free
fpga_image_info.

Getting a FPGA manager has been separated from
locking it.  So an unlocked reference can be saved and
only locked when we're about to program.

A document for fpga-region has been added as well.

Signed-off-by: Alan Tull <atull@kernel.org>
---
 Documentation/fpga/fpga-mgr.txt    | 133 +++++++++++++++++++------------------
 Documentation/fpga/fpga-region.txt |  95 ++++++++++++++++++++++++++
 Documentation/fpga/overview.txt    |  23 +++++++
 3 files changed, 188 insertions(+), 63 deletions(-)
 create mode 100644 Documentation/fpga/fpga-region.txt
 create mode 100644 Documentation/fpga/overview.txt

diff --git a/Documentation/fpga/fpga-mgr.txt b/Documentation/fpga/fpga-mgr.txt
index 78f197f..0fc41eb 100644
--- a/Documentation/fpga/fpga-mgr.txt
+++ b/Documentation/fpga/fpga-mgr.txt
@@ -11,61 +11,66 @@ hidden away in a low level driver which registers a set of ops with the core.
 The FPGA image data itself is very manufacturer specific, but for our purposes
 it's just binary data.  The FPGA manager core won't parse it.
 
+The FPGA image to be programmed can be in a scatter gather list, a single
+contiguous buffer, or a firmware file.  Because allocating contiguous kernel
+memory for the buffer should be avoided, users are encouraged to use a scatter
+gather list instead if possible.
+
+The particulars for programming the image are presented in a structure (struct
+fpga_image_info).  This struct contains parameters such as pointers to the
+FPGA image as well as image-specific particulars such as whether the image was
+built for full or partial reconfiguration.
 
 API Functions:
 ==============
 
-To program the FPGA from a file or from a buffer:
--------------------------------------------------
-
-	int fpga_mgr_buf_load(struct fpga_manager *mgr,
-			      struct fpga_image_info *info,
-		              const char *buf, size_t count);
-
-Load the FPGA from an image which exists as a contiguous buffer in
-memory. Allocating contiguous kernel memory for the buffer should be avoided,
-users are encouraged to use the _sg interface instead of this.
-
-        int fpga_mgr_buf_load_sg(struct fpga_manager *mgr,
-				 struct fpga_image_info *info,
-				 struct sg_table *sgt);
+To program the FPGA:
+--------------------
 
-Load the FPGA from an image from non-contiguous in memory. Callers can
-construct a sg_table using alloc_page backed memory.
+	int fpga_mgr_load(struct fpga_manager *mgr,
+			  struct fpga_image_info *info);
 
-	int fpga_mgr_firmware_load(struct fpga_manager *mgr,
-				   struct fpga_image_info *info,
-		                   const char *image_name);
-
-Load the FPGA from an image which exists as a file.  The image file must be on
-the firmware search path (see the firmware class documentation).  If successful,
+Load the FPGA from an image which is indicated in the info.  If successful,
 the FPGA ends up in operating mode.  Return 0 on success or a negative error
 code.
 
-A FPGA design contained in a FPGA image file will likely have particulars that
-affect how the image is programmed to the FPGA.  These are contained in struct
-fpga_image_info.  Currently the only such particular is a single flag bit
-indicating whether the image is for full or partial reconfiguration.
+To allocate or free a struct fpga_image_info:
+---------------------------------------------
+
+	struct fpga_image_info *fpga_image_info_alloc(struct device *dev);
+
+	void fpga_image_info_free(struct device *dev,
+				  struct fpga_image_info *info);
 
 To get/put a reference to a FPGA manager:
 -----------------------------------------
 
 	struct fpga_manager *of_fpga_mgr_get(struct device_node *node);
 	struct fpga_manager *fpga_mgr_get(struct device *dev);
+	void fpga_mgr_put(struct fpga_manager *mgr);
 
-Given a DT node or device, get an exclusive reference to a FPGA manager.
+Given a DT node or device, get a reference to a FPGA manager.  This pointer
+can be saved until you are ready to program the FPGA.  fpga_mgr_put
+releases the reference.
 
-	void fpga_mgr_put(struct fpga_manager *mgr);
 
-Release the reference.
+To get exclusive control of a FPGA manager:
+-------------------------------------------
+
+	int fpga_mgr_lock(struct fpga_magager *mgr);
+	void fpga_mgr_unlock(struct fpga_magager *mgr);
+
+The user should call fpga_mgr_lock and verify that it returns 0 before
+attempting to program the FPGA.  Likeqise, the user should call
+fpga_mgr_unlock when done programming the FPGA.
 
 
 To register or unregister the low level FPGA-specific driver:
 -------------------------------------------------------------
 
 	int fpga_mgr_register(struct device *dev, const char *name,
-		              const struct fpga_manager_ops *mops,
-		              void *priv);
+			      const struct fpga_manager_ops *mops,
+			      void *priv);
 
 	void fpga_mgr_unregister(struct device *dev);
 
@@ -78,59 +83,61 @@ How to write an image buffer to a supported FPGA
 /* Include to get the API */
 #include <linux/fpga/fpga-mgr.h>
 
-/* device node that specifies the FPGA manager to use */
-struct device_node *mgr_node = ...
+struct fpga_manager *mgr;
+struct fpga_image_info *info;
+int ret;
 
-/* FPGA image is in this buffer.  count is size of the buffer. */
-char *buf = ...
-int count = ...
+/*
+ * Get a reference to FPGA manager.  This example uses the  device node of the
+ * manager.  You could use fpga_mgr_get() instead if you have the device instead
+ * of the device node.
+ */
+mgr = of_fpga_mgr_get(mgr_node);
 
 /* struct with information about the FPGA image to program. */
-struct fpga_image_info info;
+info = fpga_image_info_alloc(dev);
 
 /* flags indicates whether to do full or partial reconfiguration */
-info.flags = 0;
+info->flags = FPGA_MGR_PARTIAL_RECONFIG;
 
-int ret;
+/*
+ * At this point, indicate where the image is. This is pseudo-code; you're
+ * probably going to use one of these three.
+ */
+if (using scatter gather) {
 
-/* Get exclusive control of FPGA manager */
-struct fpga_manager *mgr = of_fpga_mgr_get(mgr_node);
+	info->sgt = [your scatter gather table]
 
-/* Load the buffer to the FPGA */
-ret = fpga_mgr_buf_load(mgr, &info, buf, count);
-
-/* Release the FPGA manager */
-fpga_mgr_put(mgr);
+} else if (using a buffer) {
 
+	info->buf = [your image buffer]
+	info->count = [image buffer size]
 
-How to write an image file to a supported FPGA
-==============================================
-/* Include to get the API */
-#include <linux/fpga/fpga-mgr.h>
-
-/* device node that specifies the FPGA manager to use */
-struct device_node *mgr_node = ...
+} else if (using a firmware file) {
 
-/* FPGA image is in this file which is in the firmware search path */
-const char *path = "fpga-image-9.rbf"
+	info->firmware_name = devm_kstrdup(dev, firmware_name, GFP_KERNEL);
 
-/* struct with information about the FPGA image to program. */
-struct fpga_image_info info;
+} else {
 
-/* flags indicates whether to do full or partial reconfiguration */
-info.flags = 0;
+	not implemented!
 
-int ret;
+}
 
 /* Get exclusive control of FPGA manager */
-struct fpga_manager *mgr = of_fpga_mgr_get(mgr_node);
+ret = fpga_mgr_lock(mgr);
 
-/* Get the firmware image (path) and load it to the FPGA */
-ret = fpga_mgr_firmware_load(mgr, &info, path);
+/* Load the buffer to the FPGA */
+ret = fpga_mgr_buf_load(mgr, &info, buf, count);
 
 /* Release the FPGA manager */
+fpga_mgr_unlock(mgr);
 fpga_mgr_put(mgr);
 
+/* Free your image storage in some appropriate way */
+...
+
+/* Deallocate the image info if you're done with it */
+fpga_image_info_free(dev, info);
 
 How to support a new FPGA device
 ================================
diff --git a/Documentation/fpga/fpga-region.txt b/Documentation/fpga/fpga-region.txt
new file mode 100644
index 0000000..139a02b
--- /dev/null
+++ b/Documentation/fpga/fpga-region.txt
@@ -0,0 +1,95 @@
+FPGA Regions
+
+Alan Tull 2017
+
+CONTENTS
+ - Introduction
+ - The FPGA region API
+ - Usage example
+
+Introduction
+============
+
+This document is meant to be an brief overview of the FPGA region API usage.  A
+more conceptual look at regions can be found in [1].
+
+For the purposes of this API document, let's just say that a region associates
+an FPGA Manager and a bridge (or bridges) with a reprogrammable region of an
+FPGA or the whole FPGA.  The API provides a way to register a region and to
+program a region.
+
+Currently the only layer above fpga-region.c in the kernel is the Device Tree
+support (of-fpga-region.c) described in [1].  The DT support layer uses regions
+to program the FPGA and then DT to handle enumeration.  The common region code
+is intended to be used by other schemes that have other ways of accomplishing
+enumeration after programming.
+
+An fpga-region can be set up to know the following things:
+* which FPGA manager to use to do the programming
+* which bridges to disable before programming and enable afterwards.
+
+Additional info needed to program the FPGA image is passed in the struct
+fpga_image_info [2] including:
+* pointers to the image as either a scatter-gather buffer, a contiguous
+  buffer, or the name of firmware file
+* flags indicating specifics such as whether the image if for partial
+  reconfiguration.
+
+===================
+The FPGA region API
+===================
+
+To register or unregister a region:
+-----------------------------------
+
+	int fpga_region_register(struct device *dev,
+				 struct fpga_region *region);
+	int fpga_region_unregister(struct fpga_region *region);
+
+An example of usage can be seen in the probe function of [3]
+
+To program an FPGA:
+-------------------
+	int fpga_region_program_fpga(struct fpga_region *region);
+
+This function operates on info passed in the fpga_image_info
+(region->info).
+
+This function will attempt to:
+ * lock the region's mutex
+ * lock the region's FPGA manager
+ * build a list of FPGA bridges if a method has been specified to do so
+ * disable the bridges
+ * program the FPGA
+ * re-enable the bridges
+ * release the locks
+
+=============
+Usage example
+=============
+
+First, allocate the info struct:
+
+	info = fpga_image_info_alloc(dev);
+	if (!info)
+		return -ENOMEM;
+
+Set flags as needed, i.e.
+
+	info->flags |= FPGA_MGR_PARTIAL_RECONFIG;
+
+Point to your FPGA image, such as:
+
+	info->sgt = &sgt;
+
+Add info to region and do the programming:
+
+	region->info = info;
+	ret = fpga_region_program_fpga(region);
+
+Then enumerate whatever hardware has appeared in the FPGA.
+
+--
+[1] ../devicetree/bindings/fpga/fpga-region.txt
+[2] ./fpga-mgr.txt
+[3] ../../drivers/fpga/of-fpga-region.c
diff --git a/Documentation/fpga/overview.txt b/Documentation/fpga/overview.txt
new file mode 100644
index 0000000..149ac8a
--- /dev/null
+++ b/Documentation/fpga/overview.txt
@@ -0,0 +1,23 @@
+Linux kernel FPGA support
+
+Alan Tull 2017
+
+The main point of this project has been to separate the out the upper layers
+that know when to reprogram a FPGA from the lower layers that know how to
+reprogram a specific FPGA device.  The intention is to make this manufacturor
+agnostic, understanding that of course the FPGA images are very device specific
+themselves.
+
+At this point it time, the framework in the kernel includes:
+* low level FPGA manager drivers that know how to program a specific device
+* the fpga-mgr framework they are registered with
+* low level FPGA bridge drivers for hard/soft bridges which are intended to
+  be disable during FPGA programming
+* the fpga-bridge framework they are registered with
+* the fpga-region framework which associates and controls managers and bridges
+  as reconfigurable regions
+* the of-fpga-region support for reprogramming FPGAs when device tree overlays
+  are applied.
+
+I would encourage you the user to add code that creates fpga regions rather
+that trying to control managers and bridges separately.
-- 
2.7.4

[PATCH v3 02/16] fpga: bridge: support getting bridge from device

[Alan Tull]

Add two functions for getting the FPGA bridge from the device
rather than device tree node.  This is to enable writing code
that will support using FPGA bridges without device tree.
Rename one old function to make it clear that it is device
tree-ish.  This leaves us with 3 functions for getting a bridge:

* fpga_bridge_get
  Get the bridge given the device.

* fpga_bridges_get_to_list
  Given the device, get the bridge and add it to a list.

* of_fpga_bridges_get_to_list
  Renamed from priviously existing fpga_bridges_get_to_list.
  Given the device node, get the bridge and add it to a list.

Signed-off-by: Alan Tull <atull@kernel.org>
---
 drivers/fpga/fpga-bridge.c       | 110 +++++++++++++++++++++++++++++++--------
 drivers/fpga/fpga-region.c       |  11 ++--
 include/linux/fpga/fpga-bridge.h |   7 ++-
 3 files changed, 100 insertions(+), 28 deletions(-)

diff --git a/drivers/fpga/fpga-bridge.c b/drivers/fpga/fpga-bridge.c
index 9651aa5..03f6b72 100644
--- a/drivers/fpga/fpga-bridge.c
+++ b/drivers/fpga/fpga-bridge.c
@@ -2,6 +2,7 @@
  * FPGA Bridge Framework Driver
  *
  *  Copyright (C) 2013-2016 Altera Corporation, All Rights Reserved.
+ *  Copyright (C) 2017 Intel Corporation
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -70,29 +71,12 @@ int fpga_bridge_disable(struct fpga_bridge *bridge)
 }
 EXPORT_SYMBOL_GPL(fpga_bridge_disable);
 
-/**
- * of_fpga_bridge_get - get an exclusive reference to a fpga bridge
- *
- * @np: node pointer of a FPGA bridge
- * @info: fpga image specific information
- *
- * Return fpga_bridge struct if successful.
- * Return -EBUSY if someone already has a reference to the bridge.
- * Return -ENODEV if @np is not a FPGA Bridge.
- */
-struct fpga_bridge *of_fpga_bridge_get(struct device_node *np,
-				       struct fpga_image_info *info)
-
+struct fpga_bridge *__fpga_bridge_get(struct device *dev,
+				      struct fpga_image_info *info)
 {
-	struct device *dev;
 	struct fpga_bridge *bridge;
 	int ret = -ENODEV;
 
-	dev = class_find_device(fpga_bridge_class, NULL, np,
-				fpga_bridge_of_node_match);
-	if (!dev)
-		goto err_dev;
-
 	bridge = to_fpga_bridge(dev);
 	if (!bridge)
 		goto err_dev;
@@ -117,8 +101,58 @@ struct fpga_bridge *of_fpga_bridge_get(struct device_node *np,
 	put_device(dev);
 	return ERR_PTR(ret);
 }
+
+/**
+ * of_fpga_bridge_get - get an exclusive reference to a fpga bridge
+ *
+ * @np: node pointer of a FPGA bridge
+ * @info: fpga image specific information
+ *
+ * Return fpga_bridge struct if successful.
+ * Return -EBUSY if someone already has a reference to the bridge.
+ * Return -ENODEV if @np is not a FPGA Bridge.
+ */
+struct fpga_bridge *of_fpga_bridge_get(struct device_node *np,
+				       struct fpga_image_info *info)
+{
+	struct device *dev;
+
+	dev = class_find_device(fpga_bridge_class, NULL, np,
+				fpga_bridge_of_node_match);
+	if (!dev)
+		return ERR_PTR(-ENODEV);
+
+	return __fpga_bridge_get(dev, info);
+}
 EXPORT_SYMBOL_GPL(of_fpga_bridge_get);
 
+static int fpga_bridge_dev_match(struct device *dev, const void *data)
+{
+	return dev->parent == data;
+}
+
+/**
+ * fpga_bridge_get - get an exclusive reference to a fpga bridge
+ * @dev:	parent device that fpga bridge was registered with
+ *
+ * Given a device, get an exclusive reference to a fpga bridge.
+ *
+ * Return: fpga manager struct or IS_ERR() condition containing error code.
+ */
+struct fpga_bridge *fpga_bridge_get(struct device *dev,
+				    struct fpga_image_info *info)
+{
+	struct device *bridge_dev;
+
+	bridge_dev = class_find_device(fpga_bridge_class, NULL, dev,
+				       fpga_bridge_dev_match);
+	if (!bridge_dev)
+		return ERR_PTR(-ENODEV);
+
+	return __fpga_bridge_get(bridge_dev, info);
+}
+EXPORT_SYMBOL_GPL(fpga_bridge_get);
+
 /**
  * fpga_bridge_put - release a reference to a bridge
  *
@@ -206,7 +240,7 @@ void fpga_bridges_put(struct list_head *bridge_list)
 EXPORT_SYMBOL_GPL(fpga_bridges_put);
 
 /**
- * fpga_bridges_get_to_list - get a bridge, add it to a list
+ * of_fpga_bridge_get_to_list - get a bridge, add it to a list
  *
  * @np: node pointer of a FPGA bridge
  * @info: fpga image specific information
@@ -216,14 +250,44 @@ EXPORT_SYMBOL_GPL(fpga_bridges_put);
  *
  * Return 0 for success, error code from of_fpga_bridge_get() othewise.
  */
-int fpga_bridge_get_to_list(struct device_node *np,
+int of_fpga_bridge_get_to_list(struct device_node *np,
+			       struct fpga_image_info *info,
+			       struct list_head *bridge_list)
+{
+	struct fpga_bridge *bridge;
+	unsigned long flags;
+
+	bridge = of_fpga_bridge_get(np, info);
+	if (IS_ERR(bridge))
+		return PTR_ERR(bridge);
+
+	spin_lock_irqsave(&bridge_list_lock, flags);
+	list_add(&bridge->node, bridge_list);
+	spin_unlock_irqrestore(&bridge_list_lock, flags);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(of_fpga_bridge_get_to_list);
+
+/**
+ * fpga_bridge_get_to_list - given device, get a bridge, add it to a list
+ *
+ * @dev: FPGA bridge device
+ * @info: fpga image specific information
+ * @bridge_list: list of FPGA bridges
+ *
+ * Get an exclusive reference to the bridge and and it to the list.
+ *
+ * Return 0 for success, error code from fpga_bridge_get() othewise.
+ */
+int fpga_bridge_get_to_list(struct device *dev,
 			    struct fpga_image_info *info,
 			    struct list_head *bridge_list)
 {
 	struct fpga_bridge *bridge;
 	unsigned long flags;
 
-	bridge = of_fpga_bridge_get(np, info);
+	bridge = fpga_bridge_get(dev, info);
 	if (IS_ERR(bridge))
 		return PTR_ERR(bridge);
 
@@ -381,7 +445,7 @@ static void __exit fpga_bridge_dev_exit(void)
 }
 
 MODULE_DESCRIPTION("FPGA Bridge Driver");
-MODULE_AUTHOR("Alan Tull <atull@opensource.altera.com>");
+MODULE_AUTHOR("Alan Tull <atull@kernel.org>");
 MODULE_LICENSE("GPL v2");
 
 subsys_initcall(fpga_bridge_dev_init);
diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index 3b6b2f4..655940f 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -183,11 +183,14 @@ static int fpga_region_get_bridges(struct fpga_region *region,
 	int i, ret;
 
 	/* If parent is a bridge, add to list */
-	ret = fpga_bridge_get_to_list(region_np->parent, region->info,
-				      &region->bridge_list);
+	ret = of_fpga_bridge_get_to_list(region_np->parent, region->info,
+					 &region->bridge_list);
+
+	/* -EBUSY means parent is a bridge that is under use. Give up. */
 	if (ret == -EBUSY)
 		return ret;
 
+	/* Zero return code means parent was a bridge and was added to list. */
 	if (!ret)
 		parent_br = region_np->parent;
 
@@ -207,8 +210,8 @@ static int fpga_region_get_bridges(struct fpga_region *region,
 			continue;
 
 		/* If node is a bridge, get it and add to list */
-		ret = fpga_bridge_get_to_list(br, region->info,
-					      &region->bridge_list);
+		ret = of_fpga_bridge_get_to_list(br, region->info,
+						 &region->bridge_list);
 
 		/* If any of the bridges are in use, give up */
 		if (ret == -EBUSY) {
diff --git a/include/linux/fpga/fpga-bridge.h b/include/linux/fpga/fpga-bridge.h
index dba6e3c..9f6696b 100644
--- a/include/linux/fpga/fpga-bridge.h
+++ b/include/linux/fpga/fpga-bridge.h
@@ -42,6 +42,8 @@ struct fpga_bridge {
 
 struct fpga_bridge *of_fpga_bridge_get(struct device_node *node,
 				       struct fpga_image_info *info);
+struct fpga_bridge *fpga_bridge_get(struct device *dev,
+				    struct fpga_image_info *info);
 void fpga_bridge_put(struct fpga_bridge *bridge);
 int fpga_bridge_enable(struct fpga_bridge *bridge);
 int fpga_bridge_disable(struct fpga_bridge *bridge);
@@ -49,9 +51,12 @@ int fpga_bridge_disable(struct fpga_bridge *bridge);
 int fpga_bridges_enable(struct list_head *bridge_list);
 int fpga_bridges_disable(struct list_head *bridge_list);
 void fpga_bridges_put(struct list_head *bridge_list);
-int fpga_bridge_get_to_list(struct device_node *np,
+int fpga_bridge_get_to_list(struct device *dev,
 			    struct fpga_image_info *info,
 			    struct list_head *bridge_list);
+int of_fpga_bridge_get_to_list(struct device_node *np,
+			       struct fpga_image_info *info,
+			       struct list_head *bridge_list);
 
 int fpga_bridge_register(struct device *dev, const char *name,
 			 const struct fpga_bridge_ops *br_ops, void *priv);
-- 
2.7.4

[PATCH v3 03/16] fpga: mgr: API change to replace fpga load functions with single function

[Alan Tull]

fpga-mgr has three methods for programming FPGAs, depending on
whether the image is in a scatter gather list, a contiguous
buffer, or a firmware file. This makes it difficult to write
upper layers as the caller has to assume whether the FPGA image
is in a sg table, as a single buffer, or a firmware file.
This commit moves these parameters to struct fpga_image_info
and adds a single function for programming fpgas.

New functions:
* fpga_mgr_load - given fpga manager and struct fpga_image_info,
   program the fpga.

* fpga_image_info_alloc - alloc a struct fpga_image_info.

* fpga_image_info_free - free a struct fpga_image_info.

These three functions are unexported:
* fpga_mgr_buf_load_sg
* fpga_mgr_buf_load
* fpga_mgr_firmware_load

Also use devm_kstrdup to copy firmware_name so we aren't making
assumptions about where it comes from when allocing/freeing the
struct fpga_image_info.

Signed-off-by: Alan Tull <atull@kernel.org>
---
 drivers/fpga/fpga-mgr.c       | 59 +++++++++++++++++++++++++++++++++++--------
 drivers/fpga/fpga-region.c    | 43 ++++++++++++++++++++-----------
 include/linux/fpga/fpga-mgr.h | 22 ++++++++++------
 3 files changed, 90 insertions(+), 34 deletions(-)

diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
index 188ffef..3478aab 100644
--- a/drivers/fpga/fpga-mgr.c
+++ b/drivers/fpga/fpga-mgr.c
@@ -2,6 +2,7 @@
  * FPGA Manager Core
  *
  *  Copyright (C) 2013-2015 Altera Corporation
+ *  Copyright (C) 2017 Intel Corporation
  *
  * With code from the mailing list:
  * Copyright (C) 2013 Xilinx, Inc.
@@ -31,6 +32,31 @@
 static DEFINE_IDA(fpga_mgr_ida);
 static struct class *fpga_mgr_class;
 
+struct fpga_image_info *fpga_image_info_alloc(struct device *dev)
+{
+	struct fpga_image_info *info;
+
+	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
+	if (!info)
+		return ERR_PTR(-ENOMEM);
+
+	return info;
+}
+EXPORT_SYMBOL_GPL(fpga_image_info_alloc);
+
+void fpga_image_info_free(struct device *dev,
+			  struct fpga_image_info *info)
+{
+	if (!info)
+		return;
+
+	if (info->firmware_name)
+		devm_kfree(dev, info->firmware_name);
+
+	devm_kfree(dev, info);
+}
+EXPORT_SYMBOL_GPL(fpga_image_info_free);
+
 /*
  * Call the low level driver's write_init function.  This will do the
  * device-specific things to get the FPGA into the state where it is ready to
@@ -137,8 +163,9 @@ static int fpga_mgr_write_complete(struct fpga_manager *mgr,
  *
  * Return: 0 on success, negative error code otherwise.
  */
-int fpga_mgr_buf_load_sg(struct fpga_manager *mgr, struct fpga_image_info *info,
-			 struct sg_table *sgt)
+static int fpga_mgr_buf_load_sg(struct fpga_manager *mgr,
+				struct fpga_image_info *info,
+				struct sg_table *sgt)
 {
 	int ret;
 
@@ -170,7 +197,6 @@ int fpga_mgr_buf_load_sg(struct fpga_manager *mgr, struct fpga_image_info *info,
 
 	return fpga_mgr_write_complete(mgr, info);
 }
-EXPORT_SYMBOL_GPL(fpga_mgr_buf_load_sg);
 
 static int fpga_mgr_buf_load_mapped(struct fpga_manager *mgr,
 				    struct fpga_image_info *info,
@@ -210,8 +236,9 @@ static int fpga_mgr_buf_load_mapped(struct fpga_manager *mgr,
  *
  * Return: 0 on success, negative error code otherwise.
  */
-int fpga_mgr_buf_load(struct fpga_manager *mgr, struct fpga_image_info *info,
-		      const char *buf, size_t count)
+static int fpga_mgr_buf_load(struct fpga_manager *mgr,
+			     struct fpga_image_info *info,
+			     const char *buf, size_t count)
 {
 	struct page **pages;
 	struct sg_table sgt;
@@ -266,7 +293,6 @@ int fpga_mgr_buf_load(struct fpga_manager *mgr, struct fpga_image_info *info,
 
 	return rc;
 }
-EXPORT_SYMBOL_GPL(fpga_mgr_buf_load);
 
 /**
  * fpga_mgr_firmware_load - request firmware and load to fpga
@@ -282,9 +308,9 @@ EXPORT_SYMBOL_GPL(fpga_mgr_buf_load);
  *
  * Return: 0 on success, negative error code otherwise.
  */
-int fpga_mgr_firmware_load(struct fpga_manager *mgr,
-			   struct fpga_image_info *info,
-			   const char *image_name)
+static int fpga_mgr_firmware_load(struct fpga_manager *mgr,
+				  struct fpga_image_info *info,
+				  const char *image_name)
 {
 	struct device *dev = &mgr->dev;
 	const struct firmware *fw;
@@ -307,7 +333,18 @@ int fpga_mgr_firmware_load(struct fpga_manager *mgr,
 
 	return ret;
 }
-EXPORT_SYMBOL_GPL(fpga_mgr_firmware_load);
+
+int fpga_mgr_load(struct fpga_manager *mgr, struct fpga_image_info *info)
+{
+	if (info->sgt)
+		return fpga_mgr_buf_load_sg(mgr, info, info->sgt);
+	if (info->buf && info->count)
+		return fpga_mgr_buf_load(mgr, info, info->buf, info->count);
+	if (info->firmware_name)
+		return fpga_mgr_firmware_load(mgr, info, info->firmware_name);
+	return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(fpga_mgr_load);
 
 static const char * const state_str[] = {
 	[FPGA_MGR_STATE_UNKNOWN] =		"unknown",
@@ -578,7 +615,7 @@ static void __exit fpga_mgr_class_exit(void)
 	ida_destroy(&fpga_mgr_ida);
 }
 
-MODULE_AUTHOR("Alan Tull <atull@opensource.altera.com>");
+MODULE_AUTHOR("Alan Tull <atull@kernel.org>");
 MODULE_DESCRIPTION("FPGA manager framework");
 MODULE_LICENSE("GPL v2");
 
diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index 655940f..c71c9cb 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -226,14 +226,11 @@ static int fpga_region_get_bridges(struct fpga_region *region,
 /**
  * fpga_region_program_fpga - program FPGA
  * @region: FPGA region
- * @firmware_name: name of FPGA image firmware file
  * @overlay: device node of the overlay
- * Program an FPGA using information in the device tree.
- * Function assumes that there is a firmware-name property.
+ * Program an FPGA using information in the region's fpga image info.
  * Return 0 for success or negative error code.
  */
 static int fpga_region_program_fpga(struct fpga_region *region,
-				    const char *firmware_name,
 				    struct device_node *overlay)
 {
 	struct fpga_manager *mgr;
@@ -264,7 +261,7 @@ static int fpga_region_program_fpga(struct fpga_region *region,
 		goto err_put_br;
 	}
 
-	ret = fpga_mgr_firmware_load(mgr, region->info, firmware_name);
+	ret = fpga_mgr_load(mgr, region->info);
 	if (ret) {
 		pr_err("failed to load fpga image\n");
 		goto err_put_br;
@@ -357,16 +354,15 @@ static int child_regions_with_firmware(struct device_node *overlay)
 static int fpga_region_notify_pre_apply(struct fpga_region *region,
 					struct of_overlay_notify_data *nd)
 {
-	const char *firmware_name = NULL;
+	struct device *dev = &region->dev;
 	struct fpga_image_info *info;
+	const char *firmware_name;
 	int ret;
 
-	info = devm_kzalloc(&region->dev, sizeof(*info), GFP_KERNEL);
+	info = fpga_image_info_alloc(dev);
 	if (!info)
 		return -ENOMEM;
 
-	region->info = info;
-
 	/* Reject overlay if child FPGA Regions have firmware-name property */
 	ret = child_regions_with_firmware(nd->overlay);
 	if (ret)
@@ -382,7 +378,13 @@ static int fpga_region_notify_pre_apply(struct fpga_region *region,
 	if (of_property_read_bool(nd->overlay, "encrypted-fpga-config"))
 		info->flags |= FPGA_MGR_ENCRYPTED_BITSTREAM;
 
-	of_property_read_string(nd->overlay, "firmware-name", &firmware_name);
+	if (!of_property_read_string(nd->overlay, "firmware-name",
+				     &firmware_name)) {
+		info->firmware_name = devm_kstrdup(dev, firmware_name,
+						   GFP_KERNEL);
+		if (!info->firmware_name)
+			return -ENOMEM;
+	}
 
 	of_property_read_u32(nd->overlay, "region-unfreeze-timeout-us",
 			     &info->enable_timeout_us);
@@ -394,22 +396,33 @@ static int fpga_region_notify_pre_apply(struct fpga_region *region,
 			     &info->config_complete_timeout_us);
 
 	/* If FPGA was externally programmed, don't specify firmware */
-	if ((info->flags & FPGA_MGR_EXTERNAL_CONFIG) && firmware_name) {
+	if ((info->flags & FPGA_MGR_EXTERNAL_CONFIG) && info->firmware_name) {
 		pr_err("error: specified firmware and external-fpga-config");
+		fpga_image_info_free(dev, info);
 		return -EINVAL;
 	}
 
 	/* FPGA is already configured externally.  We're done. */
-	if (info->flags & FPGA_MGR_EXTERNAL_CONFIG)
+	if (info->flags & FPGA_MGR_EXTERNAL_CONFIG) {
+		fpga_image_info_free(dev, info);
 		return 0;
+	}
 
 	/* If we got this far, we should be programming the FPGA */
-	if (!firmware_name) {
+	if (!info->firmware_name) {
 		pr_err("should specify firmware-name or external-fpga-config\n");
+		fpga_image_info_free(dev, info);
 		return -EINVAL;
 	}
 
-	return fpga_region_program_fpga(region, firmware_name, nd->overlay);
+	region->info = info;
+	ret = fpga_region_program_fpga(region, nd->overlay);
+	if (ret) {
+		fpga_image_info_free(dev, info);
+		region->info = NULL;
+	}
+
+	return ret;
 }
 
 /**
@@ -426,7 +439,7 @@ static void fpga_region_notify_post_remove(struct fpga_region *region,
 {
 	fpga_bridges_disable(&region->bridge_list);
 	fpga_bridges_put(&region->bridge_list);
-	devm_kfree(&region->dev, region->info);
+	fpga_image_info_free(&region->dev, region->info);
 	region->info = NULL;
 }
 
diff --git a/include/linux/fpga/fpga-mgr.h b/include/linux/fpga/fpga-mgr.h
index b4ac24c..1c53aa3 100644
--- a/include/linux/fpga/fpga-mgr.h
+++ b/include/linux/fpga/fpga-mgr.h
@@ -1,7 +1,8 @@
 /*
  * FPGA Framework
  *
- *  Copyright (C) 2013-2015 Altera Corporation
+ *  Copyright (C) 2013-2016 Altera Corporation
+ *  Copyright (C) 2017 Intel Corporation
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -79,12 +80,20 @@ enum fpga_mgr_states {
  * @disable_timeout_us: maximum time to disable traffic through bridge (uSec)
  * @config_complete_timeout_us: maximum time for FPGA to switch to operating
  *	   status in the write_complete op.
+ * @firmware_name: name of FPGA image firmware file
+ * @sgt: scatter/gather table containing FPGA image
+ * @buf: contiguous buffer containing FPGA image
+ * @count: size of buf
  */
 struct fpga_image_info {
 	u32 flags;
 	u32 enable_timeout_us;
 	u32 disable_timeout_us;
 	u32 config_complete_timeout_us;
+	char *firmware_name;
+	struct sg_table *sgt;
+	const char *buf;
+	size_t count;
 };
 
 /**
@@ -134,14 +143,11 @@ struct fpga_manager {
 
 #define to_fpga_manager(d) container_of(d, struct fpga_manager, dev)
 
-int fpga_mgr_buf_load(struct fpga_manager *mgr, struct fpga_image_info *info,
-		      const char *buf, size_t count);
-int fpga_mgr_buf_load_sg(struct fpga_manager *mgr, struct fpga_image_info *info,
-			 struct sg_table *sgt);
+struct fpga_image_info *fpga_image_info_alloc(struct device *dev);
 
-int fpga_mgr_firmware_load(struct fpga_manager *mgr,
-			   struct fpga_image_info *info,
-			   const char *image_name);
+void fpga_image_info_free(struct device *dev, struct fpga_image_info *info);
+
+int fpga_mgr_load(struct fpga_manager *mgr, struct fpga_image_info *info);
 
 struct fpga_manager *of_fpga_mgr_get(struct device_node *node);
 
-- 
2.7.4

[PATCH v3 04/16] fpga: mgr: separate getting/locking FPGA manager

[Alan Tull]

This commit makes it straightforward to save a reference to an
FPGA manager and only lock it when programming the FPGA.

Add functions that get an FPGA manager's mutex for exclusive use:
* fpga_mgr_lock
* fpga_mgr_unlock

The following functions no longer lock an FPGA manager's mutex:
* of_fpga_mgr_get
* fpga_mgr_get
* fpga_mgr_put

Signed-off-by: Alan Tull <atull@kernel.org>
---
 drivers/fpga/fpga-mgr.c       | 52 ++++++++++++++++++++++++++++++-------------
 drivers/fpga/fpga-region.c    | 14 ++++++++++--
 include/linux/fpga/fpga-mgr.h |  3 +++
 3 files changed, 51 insertions(+), 18 deletions(-)

diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
index 3478aab..be13cce 100644
--- a/drivers/fpga/fpga-mgr.c
+++ b/drivers/fpga/fpga-mgr.c
@@ -401,28 +401,19 @@ ATTRIBUTE_GROUPS(fpga_mgr);
 static struct fpga_manager *__fpga_mgr_get(struct device *dev)
 {
 	struct fpga_manager *mgr;
-	int ret = -ENODEV;
 
 	mgr = to_fpga_manager(dev);
 	if (!mgr)
 		goto err_dev;
 
-	/* Get exclusive use of fpga manager */
-	if (!mutex_trylock(&mgr->ref_mutex)) {
-		ret = -EBUSY;
-		goto err_dev;
-	}
-
 	if (!try_module_get(dev->parent->driver->owner))
-		goto err_ll_mod;
+		goto err_dev;
 
 	return mgr;
 
-err_ll_mod:
-	mutex_unlock(&mgr->ref_mutex);
 err_dev:
 	put_device(dev);
-	return ERR_PTR(ret);
+	return ERR_PTR(-ENODEV);
 }
 
 static int fpga_mgr_dev_match(struct device *dev, const void *data)
@@ -431,10 +422,10 @@ static int fpga_mgr_dev_match(struct device *dev, const void *data)
 }
 
 /**
- * fpga_mgr_get - get an exclusive reference to a fpga mgr
+ * fpga_mgr_get - get a reference to a fpga mgr
  * @dev:	parent device that fpga mgr was registered with
  *
- * Given a device, get an exclusive reference to a fpga mgr.
+ * Given a device, get a reference to a fpga mgr.
  *
  * Return: fpga manager struct or IS_ERR() condition containing error code.
  */
@@ -455,10 +446,10 @@ static int fpga_mgr_of_node_match(struct device *dev, const void *data)
 }
 
 /**
- * of_fpga_mgr_get - get an exclusive reference to a fpga mgr
+ * of_fpga_mgr_get - get a reference to a fpga mgr
  * @node:	device node
  *
- * Given a device node, get an exclusive reference to a fpga mgr.
+ * Given a device node, get a reference to a fpga mgr.
  *
  * Return: fpga manager struct or IS_ERR() condition containing error code.
  */
@@ -482,12 +473,41 @@ EXPORT_SYMBOL_GPL(of_fpga_mgr_get);
 void fpga_mgr_put(struct fpga_manager *mgr)
 {
 	module_put(mgr->dev.parent->driver->owner);
-	mutex_unlock(&mgr->ref_mutex);
 	put_device(&mgr->dev);
 }
 EXPORT_SYMBOL_GPL(fpga_mgr_put);
 
 /**
+ * fpga_mgr_lock - Lock FPGA manager for exclusive use
+ * @mgr:	fpga manager
+ *
+ * Given a pointer to FPGA Manager (from fpga_mgr_get() or
+ * of_fpga_mgr_put()) attempt to get the mutex.
+ *
+ * Return: 0 for success or -EBUSY
+ */
+int fpga_mgr_lock(struct fpga_manager *mgr)
+{
+	if (!mutex_trylock(&mgr->ref_mutex)) {
+		dev_err(&mgr->dev, "FPGA manager is in use.\n");
+		return -EBUSY;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(fpga_mgr_lock);
+
+/**
+ * fpga_mgr_unlock - Unlock FPGA manager
+ * @mgr:	fpga manager
+ */
+void fpga_mgr_unlock(struct fpga_manager *mgr)
+{
+	mutex_unlock(&mgr->ref_mutex);
+}
+EXPORT_SYMBOL_GPL(fpga_mgr_unlock);
+
+/**
  * fpga_mgr_register - register a low level fpga manager driver
  * @dev:	fpga manager device from pdev
  * @name:	fpga manager name
diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index c71c9cb..c6b2d46 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -125,7 +125,7 @@ static void fpga_region_put(struct fpga_region *region)
 }
 
 /**
- * fpga_region_get_manager - get exclusive reference for FPGA manager
+ * fpga_region_get_manager - get reference for FPGA manager
  * @region: FPGA region
  *
  * Get FPGA Manager from "fpga-mgr" property or from ancestor region.
@@ -233,6 +233,7 @@ static int fpga_region_get_bridges(struct fpga_region *region,
 static int fpga_region_program_fpga(struct fpga_region *region,
 				    struct device_node *overlay)
 {
+	struct device *dev = &region->dev;
 	struct fpga_manager *mgr;
 	int ret;
 
@@ -249,10 +250,16 @@ static int fpga_region_program_fpga(struct fpga_region *region,
 		goto err_put_region;
 	}
 
+	ret = fpga_mgr_lock(mgr);
+	if (ret) {
+		dev_err(dev, "FPGA manager is busy\n");
+		goto err_put_mgr;
+	}
+
 	ret = fpga_region_get_bridges(region, overlay);
 	if (ret) {
 		pr_err("failed to get fpga region bridges\n");
-		goto err_put_mgr;
+		goto err_unlock_mgr;
 	}
 
 	ret = fpga_bridges_disable(&region->bridge_list);
@@ -273,6 +280,7 @@ static int fpga_region_program_fpga(struct fpga_region *region,
 		goto err_put_br;
 	}
 
+	fpga_mgr_unlock(mgr);
 	fpga_mgr_put(mgr);
 	fpga_region_put(region);
 
@@ -280,6 +288,8 @@ static int fpga_region_program_fpga(struct fpga_region *region,
 
 err_put_br:
 	fpga_bridges_put(&region->bridge_list);
+err_unlock_mgr:
+	fpga_mgr_unlock(mgr);
 err_put_mgr:
 	fpga_mgr_put(mgr);
 err_put_region:
diff --git a/include/linux/fpga/fpga-mgr.h b/include/linux/fpga/fpga-mgr.h
index 1c53aa3..4e14bdb 100644
--- a/include/linux/fpga/fpga-mgr.h
+++ b/include/linux/fpga/fpga-mgr.h
@@ -149,6 +149,9 @@ void fpga_image_info_free(struct device *dev, struct fpga_image_info *info);
 
 int fpga_mgr_load(struct fpga_manager *mgr, struct fpga_image_info *info);
 
+int fpga_mgr_lock(struct fpga_manager *mgr);
+void fpga_mgr_unlock(struct fpga_manager *mgr);
+
 struct fpga_manager *of_fpga_mgr_get(struct device_node *node);
 
 struct fpga_manager *fpga_mgr_get(struct device *dev);
-- 
2.7.4

[PATCH v3 05/16] fpga: region: use dev_err instead of pr_err

[Alan Tull]

Use dev_err messages instead of pr_err.

Also s/&region->dev/dev/ in two places where we already
have dev = &region->dev.

Signed-off-by: Alan Tull <atull@kernel.org>
---
 drivers/fpga/fpga-region.c | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index c6b2d46..a2a8e93 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -102,7 +102,7 @@ static struct fpga_region *fpga_region_get(struct fpga_region *region)
 		return ERR_PTR(-ENODEV);
 	}
 
-	dev_dbg(&region->dev, "get\n");
+	dev_dbg(dev, "get\n");
 
 	return region;
 }
@@ -116,7 +116,7 @@ static void fpga_region_put(struct fpga_region *region)
 {
 	struct device *dev = &region->dev;
 
-	dev_dbg(&region->dev, "put\n");
+	dev_dbg(dev, "put\n");
 
 	module_put(dev->parent->driver->owner);
 	of_node_put(dev->of_node);
@@ -239,13 +239,13 @@ static int fpga_region_program_fpga(struct fpga_region *region,
 
 	region = fpga_region_get(region);
 	if (IS_ERR(region)) {
-		pr_err("failed to get fpga region\n");
+		dev_err(dev, "failed to get FPGA region\n");
 		return PTR_ERR(region);
 	}
 
 	mgr = fpga_region_get_manager(region);
 	if (IS_ERR(mgr)) {
-		pr_err("failed to get fpga region manager\n");
+		dev_err(dev, "failed to get FPGA manager\n");
 		ret = PTR_ERR(mgr);
 		goto err_put_region;
 	}
@@ -258,25 +258,25 @@ static int fpga_region_program_fpga(struct fpga_region *region,
 
 	ret = fpga_region_get_bridges(region, overlay);
 	if (ret) {
-		pr_err("failed to get fpga region bridges\n");
+		dev_err(dev, "failed to get FPGA bridges\n");
 		goto err_unlock_mgr;
 	}
 
 	ret = fpga_bridges_disable(&region->bridge_list);
 	if (ret) {
-		pr_err("failed to disable region bridges\n");
+		dev_err(dev, "failed to disable bridges\n");
 		goto err_put_br;
 	}
 
 	ret = fpga_mgr_load(mgr, region->info);
 	if (ret) {
-		pr_err("failed to load fpga image\n");
+		dev_err(dev, "failed to load FPGA image\n");
 		goto err_put_br;
 	}
 
 	ret = fpga_bridges_enable(&region->bridge_list);
 	if (ret) {
-		pr_err("failed to enable region bridges\n");
+		dev_err(dev, "failed to enable region bridges\n");
 		goto err_put_br;
 	}
 
@@ -407,7 +407,7 @@ static int fpga_region_notify_pre_apply(struct fpga_region *region,
 
 	/* If FPGA was externally programmed, don't specify firmware */
 	if ((info->flags & FPGA_MGR_EXTERNAL_CONFIG) && info->firmware_name) {
-		pr_err("error: specified firmware and external-fpga-config");
+		dev_err(dev, "error: specified firmware and external-fpga-config");
 		fpga_image_info_free(dev, info);
 		return -EINVAL;
 	}
@@ -420,7 +420,7 @@ static int fpga_region_notify_pre_apply(struct fpga_region *region,
 
 	/* If we got this far, we should be programming the FPGA */
 	if (!info->firmware_name) {
-		pr_err("should specify firmware-name or external-fpga-config\n");
+		dev_err(dev, "should specify firmware-name or external-fpga-config\n");
 		fpga_image_info_free(dev, info);
 		return -EINVAL;
 	}
-- 
2.7.4

[PATCH v3 06/16] fpga: region: remove unneeded of_node_get and put

[Alan Tull]

Remove of_node_get/put in fpga_region_get/put.  Not
needed and will get in the way when I separate out
the common FPGA region code from Device Tree support
code.

Signed-off-by: Alan Tull <atull@kernel.org>
Acked-by: Moritz Fischer <mdf@kernel.org>
---
 drivers/fpga/fpga-region.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index a2a8e93..d42224a 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -94,9 +94,7 @@ static struct fpga_region *fpga_region_get(struct fpga_region *region)
 	}
 
 	get_device(dev);
-	of_node_get(dev->of_node);
 	if (!try_module_get(dev->parent->driver->owner)) {
-		of_node_put(dev->of_node);
 		put_device(dev);
 		mutex_unlock(&region->mutex);
 		return ERR_PTR(-ENODEV);
@@ -119,7 +117,6 @@ static void fpga_region_put(struct fpga_region *region)
 	dev_dbg(dev, "put\n");
 
 	module_put(dev->parent->driver->owner);
-	of_node_put(dev->of_node);
 	put_device(dev);
 	mutex_unlock(&region->mutex);
 }
-- 
2.7.4

[PATCH v3 07/16] fpga: region: get mgr early on

[Alan Tull]

Get the FPGA manager during region creation.

This is a baby step in refactoring the FPGA region code to
separate out common FPGA region code from FPGA region
Device Tree overlay support.

Signed-off-by: Alan Tull <atull@kernel.org>
---
 drivers/fpga/fpga-region.c | 45 +++++++++++++++++++++++----------------------
 1 file changed, 23 insertions(+), 22 deletions(-)

diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index d42224a..4f0505c 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -31,12 +31,14 @@
  * @dev: FPGA Region device
  * @mutex: enforces exclusive reference to region
  * @bridge_list: list of FPGA bridges specified in region
+ * @mgr: FPGA manager
  * @info: fpga image specific information
  */
 struct fpga_region {
 	struct device dev;
 	struct mutex mutex; /* for exclusive reference to region */
 	struct list_head bridge_list;
+	struct fpga_manager *mgr;
 	struct fpga_image_info *info;
 };
 
@@ -123,7 +125,7 @@ static void fpga_region_put(struct fpga_region *region)
 
 /**
  * fpga_region_get_manager - get reference for FPGA manager
- * @region: FPGA region
+ * @np: device node of FPGA region
  *
  * Get FPGA Manager from "fpga-mgr" property or from ancestor region.
  *
@@ -131,10 +133,8 @@ static void fpga_region_put(struct fpga_region *region)
  *
  * Return: fpga manager struct or IS_ERR() condition containing error code.
  */
-static struct fpga_manager *fpga_region_get_manager(struct fpga_region *region)
+static struct fpga_manager *fpga_region_get_manager(struct device_node *np)
 {
-	struct device *dev = &region->dev;
-	struct device_node *np = dev->of_node;
 	struct device_node  *mgr_node;
 	struct fpga_manager *mgr;
 
@@ -231,7 +231,6 @@ static int fpga_region_program_fpga(struct fpga_region *region,
 				    struct device_node *overlay)
 {
 	struct device *dev = &region->dev;
-	struct fpga_manager *mgr;
 	int ret;
 
 	region = fpga_region_get(region);
@@ -240,17 +239,10 @@ static int fpga_region_program_fpga(struct fpga_region *region,
 		return PTR_ERR(region);
 	}
 
-	mgr = fpga_region_get_manager(region);
-	if (IS_ERR(mgr)) {
-		dev_err(dev, "failed to get FPGA manager\n");
-		ret = PTR_ERR(mgr);
-		goto err_put_region;
-	}
-
-	ret = fpga_mgr_lock(mgr);
+	ret = fpga_mgr_lock(region->mgr);
 	if (ret) {
 		dev_err(dev, "FPGA manager is busy\n");
-		goto err_put_mgr;
+		goto err_put_region;
 	}
 
 	ret = fpga_region_get_bridges(region, overlay);
@@ -265,7 +257,7 @@ static int fpga_region_program_fpga(struct fpga_region *region,
 		goto err_put_br;
 	}
 
-	ret = fpga_mgr_load(mgr, region->info);
+	ret = fpga_mgr_load(region->mgr, region->info);
 	if (ret) {
 		dev_err(dev, "failed to load FPGA image\n");
 		goto err_put_br;
@@ -277,8 +269,7 @@ static int fpga_region_program_fpga(struct fpga_region *region,
 		goto err_put_br;
 	}
 
-	fpga_mgr_unlock(mgr);
-	fpga_mgr_put(mgr);
+	fpga_mgr_unlock(region->mgr);
 	fpga_region_put(region);
 
 	return 0;
@@ -286,9 +277,7 @@ static int fpga_region_program_fpga(struct fpga_region *region,
 err_put_br:
 	fpga_bridges_put(&region->bridge_list);
 err_unlock_mgr:
-	fpga_mgr_unlock(mgr);
-err_put_mgr:
-	fpga_mgr_put(mgr);
+	fpga_mgr_unlock(region->mgr);
 err_put_region:
 	fpga_region_put(region);
 
@@ -517,11 +506,20 @@ static int fpga_region_probe(struct platform_device *pdev)
 	struct device *dev = &pdev->dev;
 	struct device_node *np = dev->of_node;
 	struct fpga_region *region;
+	struct fpga_manager *mgr;
 	int id, ret = 0;
 
+	mgr = fpga_region_get_manager(np);
+	if (IS_ERR(mgr))
+		return -EPROBE_DEFER;
+
 	region = kzalloc(sizeof(*region), GFP_KERNEL);
-	if (!region)
-		return -ENOMEM;
+	if (!region) {
+		ret = -ENOMEM;
+		goto err_put_mgr;
+	}
+
+	region->mgr = mgr;
 
 	id = ida_simple_get(&fpga_region_ida, 0, 0, GFP_KERNEL);
 	if (id < 0) {
@@ -557,6 +555,8 @@ static int fpga_region_probe(struct platform_device *pdev)
 	ida_simple_remove(&fpga_region_ida, id);
 err_kfree:
 	kfree(region);
+err_put_mgr:
+	fpga_mgr_put(mgr);
 
 	return ret;
 }
@@ -566,6 +566,7 @@ static int fpga_region_remove(struct platform_device *pdev)
 	struct fpga_region *region = platform_get_drvdata(pdev);
 
 	device_unregister(&region->dev);
+	fpga_mgr_put(region->mgr);
 
 	return 0;
 }
-- 
2.7.4

[PATCH v3 08/16] fpga: region: check for child regions before allocing image info

[Alan Tull]

During a device tree overlay pre-apply notification, the check
for child FPGA regions can happen slightly earlier.  This saves
us from allocating the FPGA image info that just gets thrown
away.

This is a baby step in refactoring the FPGA region code to
separate out common FPGA region code from FPGA region
Device Tree overlay support.

Signed-off-by: Alan Tull <atull@kernel.org>
Acked-by: Moritz Fischer <mdf@kernel.org>
---
 drivers/fpga/fpga-region.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index 4f0505c..0c72381 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -355,15 +355,19 @@ static int fpga_region_notify_pre_apply(struct fpga_region *region,
 	const char *firmware_name;
 	int ret;
 
-	info = fpga_image_info_alloc(dev);
-	if (!info)
-		return -ENOMEM;
-
-	/* Reject overlay if child FPGA Regions have firmware-name property */
+	/*
+	 * Reject overlay if child FPGA Regions added in the overlay have
+	 * firmware-name property (would mean that an FPGA region that has
+	 * not been added to the live tree yet is doing FPGA programming).
+	 */
 	ret = child_regions_with_firmware(nd->overlay);
 	if (ret)
 		return ret;
 
+	info = fpga_image_info_alloc(dev);
+	if (!info)
+		return -ENOMEM;
+
 	/* Read FPGA region properties from the overlay */
 	if (of_property_read_bool(nd->overlay, "partial-fpga-config"))
 		info->flags |= FPGA_MGR_PARTIAL_RECONFIG;
-- 
2.7.4

[PATCH v3 09/16] fpga: region: fix slow warning with more than one overlay

[Alan Tull]

When DT overlays are applied, each FPGA region keeps track of the fpga
image info as region->info.  This pointer is assigned only if an
overlay causes the FPGA to be programmed.  As it stands, this pointer
can be overwritten, causing a slow warning later when overlays are
removed.

This patch fixes this by changing the allowed behaviour.  If a region
has received an overlay that programmed the FPGA, reject other
overlays that try to program the FPGA.  To reprogram the FPGA, first
remove the overlay.  This makes sense as removing the overlay also
removes the devices cleanly.  Note that overlays that make DT changes
without reprogramming the FPGA are exempt from this restriction.

Signed-off-by: Alan Tull <atull@kernel.org>
---
 drivers/fpga/fpga-region.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index 0c72381..07491ad 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -355,6 +355,11 @@ static int fpga_region_notify_pre_apply(struct fpga_region *region,
 	const char *firmware_name;
 	int ret;
 
+	if (region->info) {
+		dev_err(dev, "Region already has overlay applied.\n");
+		return -EINVAL;
+	}
+
 	/*
 	 * Reject overlay if child FPGA Regions added in the overlay have
 	 * firmware-name property (would mean that an FPGA region that has
-- 
2.7.4

[PATCH v3 10/16] fpga: region: use image info as parameter for programming region

[Alan Tull]

Use FPGA image info (region->info) when region code is
programming the FPGA to pass in multiple paramaters.

This is a baby step in refactoring the FPGA region code to
separate out common FPGA region code from FPGA region
Device Tree overlay support.

Signed-off-by: Alan Tull <atull@kernel.org>
---
 drivers/fpga/fpga-region.c    | 16 +++++++++-------
 include/linux/fpga/fpga-mgr.h |  4 ++++
 2 files changed, 13 insertions(+), 7 deletions(-)

diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index 07491ad..a15c4f5 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -223,14 +223,13 @@ static int fpga_region_get_bridges(struct fpga_region *region,
 /**
  * fpga_region_program_fpga - program FPGA
  * @region: FPGA region
- * @overlay: device node of the overlay
- * Program an FPGA using information in the region's fpga image info.
+ * Program an FPGA using fpga image info (region->info).
  * Return 0 for success or negative error code.
  */
-static int fpga_region_program_fpga(struct fpga_region *region,
-				    struct device_node *overlay)
+static int fpga_region_program_fpga(struct fpga_region *region)
 {
 	struct device *dev = &region->dev;
+	struct fpga_image_info *info = region->info;
 	int ret;
 
 	region = fpga_region_get(region);
@@ -245,7 +244,7 @@ static int fpga_region_program_fpga(struct fpga_region *region,
 		goto err_put_region;
 	}
 
-	ret = fpga_region_get_bridges(region, overlay);
+	ret = fpga_region_get_bridges(region, info->overlay);
 	if (ret) {
 		dev_err(dev, "failed to get FPGA bridges\n");
 		goto err_unlock_mgr;
@@ -257,7 +256,7 @@ static int fpga_region_program_fpga(struct fpga_region *region,
 		goto err_put_br;
 	}
 
-	ret = fpga_mgr_load(region->mgr, region->info);
+	ret = fpga_mgr_load(region->mgr, info);
 	if (ret) {
 		dev_err(dev, "failed to load FPGA image\n");
 		goto err_put_br;
@@ -373,6 +372,8 @@ static int fpga_region_notify_pre_apply(struct fpga_region *region,
 	if (!info)
 		return -ENOMEM;
 
+	info->overlay = nd->overlay;
+
 	/* Read FPGA region properties from the overlay */
 	if (of_property_read_bool(nd->overlay, "partial-fpga-config"))
 		info->flags |= FPGA_MGR_PARTIAL_RECONFIG;
@@ -421,7 +422,8 @@ static int fpga_region_notify_pre_apply(struct fpga_region *region,
 	}
 
 	region->info = info;
-	ret = fpga_region_program_fpga(region, nd->overlay);
+
+	ret = fpga_region_program_fpga(region);
 	if (ret) {
 		fpga_image_info_free(dev, info);
 		region->info = NULL;
diff --git a/include/linux/fpga/fpga-mgr.h b/include/linux/fpga/fpga-mgr.h
index 4e14bdb..66d0e32 100644
--- a/include/linux/fpga/fpga-mgr.h
+++ b/include/linux/fpga/fpga-mgr.h
@@ -84,6 +84,7 @@ enum fpga_mgr_states {
  * @sgt: scatter/gather table containing FPGA image
  * @buf: contiguous buffer containing FPGA image
  * @count: size of buf
+ * @overlay: Device Tree overlay
  */
 struct fpga_image_info {
 	u32 flags;
@@ -94,6 +95,9 @@ struct fpga_image_info {
 	struct sg_table *sgt;
 	const char *buf;
 	size_t count;
+#ifdef CONFIG_OF
+	struct device_node *overlay;
+#endif
 };
 
 /**
-- 
2.7.4

[PATCH v3 11/16] fpga: region: separate out code that parses the overlay

[Alan Tull]

New function of_fpga_region_parse_ov added, moving code
from fpga_region_notify_pre_apply.  This function
gets the FPGA image info from the overlay and is able
to simplify some of the logic involved.

This is a baby step in refactoring the FPGA region code to
separate out common code from Device Tree overlay support.

Signed-off-by: Alan Tull <atull@kernel.org>
---
 drivers/fpga/fpga-region.c | 122 +++++++++++++++++++++++++++------------------
 1 file changed, 73 insertions(+), 49 deletions(-)

diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index a15c4f5..f43ce3f 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -321,33 +321,22 @@ static int child_regions_with_firmware(struct device_node *overlay)
 }
 
 /**
- * fpga_region_notify_pre_apply - pre-apply overlay notification
- *
- * @region: FPGA region that the overlay was applied to
- * @nd: overlay notification data
- *
- * Called after when an overlay targeted to a FPGA Region is about to be
- * applied.  Function will check the properties that will be added to the FPGA
- * region.  If the checks pass, it will program the FPGA.
- *
- * The checks are:
- * The overlay must add either firmware-name or external-fpga-config property
- * to the FPGA Region.
- *
- *   firmware-name         : program the FPGA
- *   external-fpga-config  : FPGA is already programmed
- *   encrypted-fpga-config : FPGA bitstream is encrypted
+ * of_fpga_region_parse_ov - parse and check overlay applied to region
  *
- * The overlay can add other FPGA regions, but child FPGA regions cannot have a
- * firmware-name property since those regions don't exist yet.
+ * @region: FPGA region
+ * @overlay: overlay applied to the FPGA region
  *
- * If the overlay that breaks the rules, notifier returns an error and the
- * overlay is rejected before it goes into the main tree.
+ * Given an overlay applied to a FPGA region, parse the FPGA image specific
+ * info in the overlay and do some checking.
  *
- * Returns 0 for success or negative error code for failure.
+ * Returns:
+ *   NULL if overlay doesn't direct us to program the FPGA.
+ *   fpga_image_info struct if there is an image to program.
+ *   error code for invalid overlay.
  */
-static int fpga_region_notify_pre_apply(struct fpga_region *region,
-					struct of_overlay_notify_data *nd)
+static struct fpga_image_info *of_fpga_region_parse_ov(
+						struct fpga_region *region,
+						struct device_node *overlay)
 {
 	struct device *dev = &region->dev;
 	struct fpga_image_info *info;
@@ -356,7 +345,7 @@ static int fpga_region_notify_pre_apply(struct fpga_region *region,
 
 	if (region->info) {
 		dev_err(dev, "Region already has overlay applied.\n");
-		return -EINVAL;
+		return ERR_PTR(-EINVAL);
 	}
 
 	/*
@@ -364,67 +353,102 @@ static int fpga_region_notify_pre_apply(struct fpga_region *region,
 	 * firmware-name property (would mean that an FPGA region that has
 	 * not been added to the live tree yet is doing FPGA programming).
 	 */
-	ret = child_regions_with_firmware(nd->overlay);
+	ret = child_regions_with_firmware(overlay);
 	if (ret)
-		return ret;
+		return ERR_PTR(ret);
 
 	info = fpga_image_info_alloc(dev);
 	if (!info)
-		return -ENOMEM;
+		return ERR_PTR(-ENOMEM);
 
-	info->overlay = nd->overlay;
+	info->overlay = overlay;
 
 	/* Read FPGA region properties from the overlay */
-	if (of_property_read_bool(nd->overlay, "partial-fpga-config"))
+	if (of_property_read_bool(overlay, "partial-fpga-config"))
 		info->flags |= FPGA_MGR_PARTIAL_RECONFIG;
 
-	if (of_property_read_bool(nd->overlay, "external-fpga-config"))
+	if (of_property_read_bool(overlay, "external-fpga-config"))
 		info->flags |= FPGA_MGR_EXTERNAL_CONFIG;
 
-	if (of_property_read_bool(nd->overlay, "encrypted-fpga-config"))
+	if (of_property_read_bool(overlay, "encrypted-fpga-config"))
 		info->flags |= FPGA_MGR_ENCRYPTED_BITSTREAM;
 
-	if (!of_property_read_string(nd->overlay, "firmware-name",
+	if (!of_property_read_string(overlay, "firmware-name",
 				     &firmware_name)) {
 		info->firmware_name = devm_kstrdup(dev, firmware_name,
 						   GFP_KERNEL);
 		if (!info->firmware_name)
-			return -ENOMEM;
+			return ERR_PTR(-ENOMEM);
 	}
 
-	of_property_read_u32(nd->overlay, "region-unfreeze-timeout-us",
+	of_property_read_u32(overlay, "region-unfreeze-timeout-us",
 			     &info->enable_timeout_us);
 
-	of_property_read_u32(nd->overlay, "region-freeze-timeout-us",
+	of_property_read_u32(overlay, "region-freeze-timeout-us",
 			     &info->disable_timeout_us);
 
-	of_property_read_u32(nd->overlay, "config-complete-timeout-us",
+	of_property_read_u32(overlay, "config-complete-timeout-us",
 			     &info->config_complete_timeout_us);
 
-	/* If FPGA was externally programmed, don't specify firmware */
-	if ((info->flags & FPGA_MGR_EXTERNAL_CONFIG) && info->firmware_name) {
-		dev_err(dev, "error: specified firmware and external-fpga-config");
-		fpga_image_info_free(dev, info);
-		return -EINVAL;
+	/* If overlay is not programming the FPGA, don't need FPGA image info */
+	if (!info->firmware_name) {
+		ret = 0;
+		goto ret_no_info;
 	}
 
-	/* FPGA is already configured externally.  We're done. */
+	/*
+	 * If overlay informs us FPGA was externally programmed, specifying
+	 * firmware here would be ambiguous.
+	 */
 	if (info->flags & FPGA_MGR_EXTERNAL_CONFIG) {
-		fpga_image_info_free(dev, info);
-		return 0;
+		dev_err(dev, "error: specified firmware and external-fpga-config");
+		ret = -EINVAL;
+		goto ret_no_info;
 	}
 
-	/* If we got this far, we should be programming the FPGA */
-	if (!info->firmware_name) {
-		dev_err(dev, "should specify firmware-name or external-fpga-config\n");
-		fpga_image_info_free(dev, info);
+	return info;
+ret_no_info:
+	fpga_image_info_free(dev, info);
+	return ERR_PTR(ret);
+}
+
+/**
+ * fpga_region_notify_pre_apply - pre-apply overlay notification
+ *
+ * @region: FPGA region that the overlay was applied to
+ * @nd: overlay notification data
+ *
+ * Called when an overlay targeted to a FPGA Region is about to be applied.
+ * Parses the overlay for properties that influence how the FPGA will be
+ * programmed and does some checking. If the checks pass, programs the FPGA.
+ * If the checks fail, overlay is rejected and does not get added to the
+ * live tree.
+ *
+ * Returns 0 for success or negative error code for failure.
+ */
+static int fpga_region_notify_pre_apply(struct fpga_region *region,
+					struct of_overlay_notify_data *nd)
+{
+	struct device *dev = &region->dev;
+	struct fpga_image_info *info;
+	int ret;
+
+	if (region->info) {
+		dev_err(dev, "Region already has overlay applied.\n");
 		return -EINVAL;
 	}
 
-	region->info = info;
+	info = of_fpga_region_parse_ov(region, nd->overlay);
+	if (IS_ERR(info))
+		return PTR_ERR(info);
+
+	if (!info)
+		return 0;
 
+	region->info = info;
 	ret = fpga_region_program_fpga(region);
 	if (ret) {
+		/* error; reject overlay */
 		fpga_image_info_free(dev, info);
 		region->info = NULL;
 	}
-- 
2.7.4

[PATCH v3 12/16] fpga: region: add fpga-region.h header

[Alan Tull]

* Create fpga-region.h.
* Export fpga_region_program_fpga.
* Move struct fpga_region and other things to the header.

This is a step in separating FPGA region common code
from Device Tree support.

Signed-off-by: Alan Tull <atull@kernel.org>
---
 drivers/fpga/fpga-region.c       | 24 ++++--------------------
 include/linux/fpga/fpga-region.h | 28 ++++++++++++++++++++++++++++
 2 files changed, 32 insertions(+), 20 deletions(-)
 create mode 100644 include/linux/fpga/fpga-region.h

diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index f43ce3f..bb10fb7 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -18,6 +18,7 @@
 
 #include <linux/fpga/fpga-bridge.h>
 #include <linux/fpga/fpga-mgr.h>
+#include <linux/fpga/fpga-region.h>
 #include <linux/idr.h>
 #include <linux/kernel.h>
 #include <linux/list.h>
@@ -26,24 +27,6 @@
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 
-/**
- * struct fpga_region - FPGA Region structure
- * @dev: FPGA Region device
- * @mutex: enforces exclusive reference to region
- * @bridge_list: list of FPGA bridges specified in region
- * @mgr: FPGA manager
- * @info: fpga image specific information
- */
-struct fpga_region {
-	struct device dev;
-	struct mutex mutex; /* for exclusive reference to region */
-	struct list_head bridge_list;
-	struct fpga_manager *mgr;
-	struct fpga_image_info *info;
-};
-
-#define to_fpga_region(d) container_of(d, struct fpga_region, dev)
-
 static DEFINE_IDA(fpga_region_ida);
 static struct class *fpga_region_class;
 
@@ -226,7 +209,7 @@ static int fpga_region_get_bridges(struct fpga_region *region,
  * Program an FPGA using fpga image info (region->info).
  * Return 0 for success or negative error code.
  */
-static int fpga_region_program_fpga(struct fpga_region *region)
+int fpga_region_program_fpga(struct fpga_region *region)
 {
 	struct device *dev = &region->dev;
 	struct fpga_image_info *info = region->info;
@@ -282,6 +265,7 @@ static int fpga_region_program_fpga(struct fpga_region *region)
 
 	return ret;
 }
+EXPORT_SYMBOL_GPL(fpga_region_program_fpga);
 
 /**
  * child_regions_with_firmware
@@ -667,5 +651,5 @@ subsys_initcall(fpga_region_init);
 module_exit(fpga_region_exit);
 
 MODULE_DESCRIPTION("FPGA Region");
-MODULE_AUTHOR("Alan Tull <atull@opensource.altera.com>");
+MODULE_AUTHOR("Alan Tull <atull@kernel.org>");
 MODULE_LICENSE("GPL v2");
diff --git a/include/linux/fpga/fpga-region.h b/include/linux/fpga/fpga-region.h
new file mode 100644
index 0000000..f84a2e1
--- /dev/null
+++ b/include/linux/fpga/fpga-region.h
@@ -0,0 +1,28 @@
+#include <linux/device.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/fpga/fpga-bridge.h>
+
+#ifndef _FPGA_REGION_H
+#define _FPGA_REGION_H
+
+/**
+ * struct fpga_region - FPGA Region structure
+ * @dev: FPGA Region device
+ * @mutex: enforces exclusive reference to region
+ * @bridge_list: list of FPGA bridges specified in region
+ * @mgr: FPGA manager
+ * @info: FPGA image info
+ */
+struct fpga_region {
+	struct device dev;
+	struct mutex mutex; /* for exclusive reference to region */
+	struct list_head bridge_list;
+	struct fpga_manager *mgr;
+	struct fpga_image_info *info;
+};
+
+#define to_fpga_region(d) container_of(d, struct fpga_region, dev)
+
+int fpga_region_program_fpga(struct fpga_region *region);
+
+#endif /* _FPGA_REGION_H */
-- 
2.7.4

[PATCH v3 13/16] fpga: region: rename some functions prior to moving

[Alan Tull]

Rename some functions that will be moved to
of-fpga-region.c.  Also change some parameters
and export a function to help with refactoring.

This is a step towards the larger goal of separating
device tree support from FPGA region common code.

* fpga_region_get_manager -> of_fpga_region_get_mgr

* add 'of_' prefix to the following:
  * fpga_region_find
  * fpga_region_get_bridges
  * fpga_region_notify_pre_apply
  * fpga_region_notify_post_remove),
  * fpga_region_probe/remove

Parameter changes:
* of_fpga_region_find
  change parameter to be the device node of the region.
* of_fpga_region_get_bridges
  change second parameter to FPGA image info.

Export of_fpga_region_find as well.

Signed-off-by: Alan Tull <atull@kernel.org>
---
 drivers/fpga/fpga-region.c | 60 ++++++++++++++++++++++++----------------------
 1 file changed, 31 insertions(+), 29 deletions(-)

diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index bb10fb7..a9b0133 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -42,12 +42,14 @@ static int fpga_region_of_node_match(struct device *dev, const void *data)
 }
 
 /**
- * fpga_region_find - find FPGA region
+ * of_fpga_region_find - find FPGA region
  * @np: device node of FPGA Region
+ *
  * Caller will need to put_device(&region->dev) when done.
+ *
  * Returns FPGA Region struct or NULL
  */
-static struct fpga_region *fpga_region_find(struct device_node *np)
+static struct fpga_region *of_fpga_region_find(struct device_node *np)
 {
 	struct device *dev;
 
@@ -107,7 +109,7 @@ static void fpga_region_put(struct fpga_region *region)
 }
 
 /**
- * fpga_region_get_manager - get reference for FPGA manager
+ * of_fpga_region_get_mgr - get reference for FPGA manager
  * @np: device node of FPGA region
  *
  * Get FPGA Manager from "fpga-mgr" property or from ancestor region.
@@ -116,7 +118,7 @@ static void fpga_region_put(struct fpga_region *region)
  *
  * Return: fpga manager struct or IS_ERR() condition containing error code.
  */
-static struct fpga_manager *fpga_region_get_manager(struct device_node *np)
+static struct fpga_manager *of_fpga_region_get_mgr(struct device_node *np)
 {
 	struct device_node  *mgr_node;
 	struct fpga_manager *mgr;
@@ -139,9 +141,9 @@ static struct fpga_manager *fpga_region_get_manager(struct device_node *np)
 }
 
 /**
- * fpga_region_get_bridges - create a list of bridges
+ * of_fpga_region_get_bridges - create a list of bridges
  * @region: FPGA region
- * @overlay: device node of the overlay
+ * @info: FPGA image info
  *
  * Create a list of bridges including the parent bridge and the bridges
  * specified by "fpga-bridges" property.  Note that the
@@ -154,8 +156,8 @@ static struct fpga_manager *fpga_region_get_manager(struct device_node *np)
  * Return 0 for success (even if there are no bridges specified)
  * or -EBUSY if any of the bridges are in use.
  */
-static int fpga_region_get_bridges(struct fpga_region *region,
-				   struct device_node *overlay)
+static int of_fpga_region_get_bridges(struct fpga_region *region,
+				      struct fpga_image_info *info)
 {
 	struct device *dev = &region->dev;
 	struct device_node *region_np = dev->of_node;
@@ -163,7 +165,7 @@ static int fpga_region_get_bridges(struct fpga_region *region,
 	int i, ret;
 
 	/* If parent is a bridge, add to list */
-	ret = of_fpga_bridge_get_to_list(region_np->parent, region->info,
+	ret = of_fpga_bridge_get_to_list(region_np->parent, info,
 					 &region->bridge_list);
 
 	/* -EBUSY means parent is a bridge that is under use. Give up. */
@@ -175,8 +177,8 @@ static int fpga_region_get_bridges(struct fpga_region *region,
 		parent_br = region_np->parent;
 
 	/* If overlay has a list of bridges, use it. */
-	if (of_parse_phandle(overlay, "fpga-bridges", 0))
-		np = overlay;
+	if (of_parse_phandle(info->overlay, "fpga-bridges", 0))
+		np = info->overlay;
 	else
 		np = region_np;
 
@@ -227,7 +229,7 @@ int fpga_region_program_fpga(struct fpga_region *region)
 		goto err_put_region;
 	}
 
-	ret = fpga_region_get_bridges(region, info->overlay);
+	ret = of_fpga_region_get_bridges(region, info);
 	if (ret) {
 		dev_err(dev, "failed to get FPGA bridges\n");
 		goto err_unlock_mgr;
@@ -397,7 +399,7 @@ static struct fpga_image_info *of_fpga_region_parse_ov(
 }
 
 /**
- * fpga_region_notify_pre_apply - pre-apply overlay notification
+ * of_fpga_region_notify_pre_apply - pre-apply overlay notification
  *
  * @region: FPGA region that the overlay was applied to
  * @nd: overlay notification data
@@ -410,8 +412,8 @@ static struct fpga_image_info *of_fpga_region_parse_ov(
  *
  * Returns 0 for success or negative error code for failure.
  */
-static int fpga_region_notify_pre_apply(struct fpga_region *region,
-					struct of_overlay_notify_data *nd)
+static int of_fpga_region_notify_pre_apply(struct fpga_region *region,
+					   struct of_overlay_notify_data *nd)
 {
 	struct device *dev = &region->dev;
 	struct fpga_image_info *info;
@@ -441,7 +443,7 @@ static int fpga_region_notify_pre_apply(struct fpga_region *region,
 }
 
 /**
- * fpga_region_notify_post_remove - post-remove overlay notification
+ * of_fpga_region_notify_post_remove - post-remove overlay notification
  *
  * @region: FPGA region that was targeted by the overlay that was removed
  * @nd: overlay notification data
@@ -449,8 +451,8 @@ static int fpga_region_notify_pre_apply(struct fpga_region *region,
  * Called after an overlay has been removed if the overlay's target was a
  * FPGA region.
  */
-static void fpga_region_notify_post_remove(struct fpga_region *region,
-					   struct of_overlay_notify_data *nd)
+static void of_fpga_region_notify_post_remove(struct fpga_region *region,
+					      struct of_overlay_notify_data *nd)
 {
 	fpga_bridges_disable(&region->bridge_list);
 	fpga_bridges_put(&region->bridge_list);
@@ -493,18 +495,18 @@ static int of_fpga_region_notify(struct notifier_block *nb,
 		return NOTIFY_OK;
 	}
 
-	region = fpga_region_find(nd->target);
+	region = of_fpga_region_find(nd->target);
 	if (!region)
 		return NOTIFY_OK;
 
 	ret = 0;
 	switch (action) {
 	case OF_OVERLAY_PRE_APPLY:
-		ret = fpga_region_notify_pre_apply(region, nd);
+		ret = of_fpga_region_notify_pre_apply(region, nd);
 		break;
 
 	case OF_OVERLAY_POST_REMOVE:
-		fpga_region_notify_post_remove(region, nd);
+		of_fpga_region_notify_post_remove(region, nd);
 		break;
 	}
 
@@ -520,7 +522,7 @@ static struct notifier_block fpga_region_of_nb = {
 	.notifier_call = of_fpga_region_notify,
 };
 
-static int fpga_region_probe(struct platform_device *pdev)
+static int of_fpga_region_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct device_node *np = dev->of_node;
@@ -528,7 +530,7 @@ static int fpga_region_probe(struct platform_device *pdev)
 	struct fpga_manager *mgr;
 	int id, ret = 0;
 
-	mgr = fpga_region_get_manager(np);
+	mgr = of_fpga_region_get_mgr(np);
 	if (IS_ERR(mgr))
 		return -EPROBE_DEFER;
 
@@ -580,7 +582,7 @@ static int fpga_region_probe(struct platform_device *pdev)
 	return ret;
 }
 
-static int fpga_region_remove(struct platform_device *pdev)
+static int of_fpga_region_remove(struct platform_device *pdev)
 {
 	struct fpga_region *region = platform_get_drvdata(pdev);
 
@@ -590,9 +592,9 @@ static int fpga_region_remove(struct platform_device *pdev)
 	return 0;
 }
 
-static struct platform_driver fpga_region_driver = {
-	.probe = fpga_region_probe,
-	.remove = fpga_region_remove,
+static struct platform_driver of_fpga_region_driver = {
+	.probe = of_fpga_region_probe,
+	.remove = of_fpga_region_remove,
 	.driver = {
 		.name	= "fpga-region",
 		.of_match_table = of_match_ptr(fpga_region_of_match),
@@ -625,7 +627,7 @@ static int __init fpga_region_init(void)
 	if (ret)
 		goto err_class;
 
-	ret = platform_driver_register(&fpga_region_driver);
+	ret = platform_driver_register(&of_fpga_region_driver);
 	if (ret)
 		goto err_plat;
 
@@ -641,7 +643,7 @@ static int __init fpga_region_init(void)
 
 static void __exit fpga_region_exit(void)
 {
-	platform_driver_unregister(&fpga_region_driver);
+	platform_driver_unregister(&of_fpga_region_driver);
 	of_overlay_notifier_unregister(&fpga_region_of_nb);
 	class_destroy(fpga_region_class);
 	ida_destroy(&fpga_region_ida);
-- 
2.7.4

[PATCH v3 14/16] fpga: region: add register/unregister functions

[Alan Tull]

Another step in separating common code from device tree specific
code for FPGA regions.

* add FPGA region register/unregister functions.
* add the register/unregister functions to the header
* use devm_kzalloc to alloc the region.
* add a method for getting bridges to the region struct
* add priv to the region struct
* use region->info in of_fpga_region_get_bridges

Signed-off-by: Alan Tull <atull@kernel.org>
---
 drivers/fpga/fpga-region.c       | 106 ++++++++++++++++++++++++---------------
 include/linux/fpga/fpga-region.h |   7 +++
 2 files changed, 72 insertions(+), 41 deletions(-)

diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index a9b0133..2e6c47b 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -143,7 +143,6 @@ static struct fpga_manager *of_fpga_region_get_mgr(struct device_node *np)
 /**
  * of_fpga_region_get_bridges - create a list of bridges
  * @region: FPGA region
- * @info: FPGA image info
  *
  * Create a list of bridges including the parent bridge and the bridges
  * specified by "fpga-bridges" property.  Note that the
@@ -156,11 +155,11 @@ static struct fpga_manager *of_fpga_region_get_mgr(struct device_node *np)
  * Return 0 for success (even if there are no bridges specified)
  * or -EBUSY if any of the bridges are in use.
  */
-static int of_fpga_region_get_bridges(struct fpga_region *region,
-				      struct fpga_image_info *info)
+static int of_fpga_region_get_bridges(struct fpga_region *region)
 {
 	struct device *dev = &region->dev;
 	struct device_node *region_np = dev->of_node;
+	struct fpga_image_info *info = region->info;
 	struct device_node *br, *np, *parent_br = NULL;
 	int i, ret;
 
@@ -192,7 +191,7 @@ static int of_fpga_region_get_bridges(struct fpga_region *region,
 			continue;
 
 		/* If node is a bridge, get it and add to list */
-		ret = of_fpga_bridge_get_to_list(br, region->info,
+		ret = of_fpga_bridge_get_to_list(br, info,
 						 &region->bridge_list);
 
 		/* If any of the bridges are in use, give up */
@@ -229,10 +228,16 @@ int fpga_region_program_fpga(struct fpga_region *region)
 		goto err_put_region;
 	}
 
-	ret = of_fpga_region_get_bridges(region, info);
-	if (ret) {
-		dev_err(dev, "failed to get FPGA bridges\n");
-		goto err_unlock_mgr;
+	/*
+	 * In some cases, we already have a list of bridges in the
+	 * fpga region struct.  Or we don't have any bridges.
+	 */
+	if (region->get_bridges) {
+		ret = region->get_bridges(region);
+		if (ret) {
+			dev_err(dev, "failed to get fpga region bridges\n");
+			goto err_unlock_mgr;
+		}
 	}
 
 	ret = fpga_bridges_disable(&region->bridge_list);
@@ -259,7 +264,8 @@ int fpga_region_program_fpga(struct fpga_region *region)
 	return 0;
 
 err_put_br:
-	fpga_bridges_put(&region->bridge_list);
+	if (region->get_bridges)
+		fpga_bridges_put(&region->bridge_list);
 err_unlock_mgr:
 	fpga_mgr_unlock(region->mgr);
 err_put_region:
@@ -522,39 +528,20 @@ static struct notifier_block fpga_region_of_nb = {
 	.notifier_call = of_fpga_region_notify,
 };
 
-static int of_fpga_region_probe(struct platform_device *pdev)
+int fpga_region_register(struct device *dev, struct fpga_region *region)
 {
-	struct device *dev = &pdev->dev;
-	struct device_node *np = dev->of_node;
-	struct fpga_region *region;
-	struct fpga_manager *mgr;
 	int id, ret = 0;
 
-	mgr = of_fpga_region_get_mgr(np);
-	if (IS_ERR(mgr))
-		return -EPROBE_DEFER;
-
-	region = kzalloc(sizeof(*region), GFP_KERNEL);
-	if (!region) {
-		ret = -ENOMEM;
-		goto err_put_mgr;
-	}
-
-	region->mgr = mgr;
-
 	id = ida_simple_get(&fpga_region_ida, 0, 0, GFP_KERNEL);
-	if (id < 0) {
-		ret = id;
-		goto err_kfree;
-	}
+	if (id < 0)
+		return id;
 
 	mutex_init(&region->mutex);
 	INIT_LIST_HEAD(&region->bridge_list);
-
 	device_initialize(&region->dev);
 	region->dev.class = fpga_region_class;
 	region->dev.parent = dev;
-	region->dev.of_node = np;
+	region->dev.of_node = dev->of_node;
 	region->dev.id = id;
 	dev_set_drvdata(dev, region);
 
@@ -566,19 +553,58 @@ static int of_fpga_region_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_remove;
 
+	return 0;
+
+err_remove:
+	ida_simple_remove(&fpga_region_ida, id);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(fpga_region_register);
+
+int fpga_region_unregister(struct fpga_region *region)
+{
+	device_unregister(&region->dev);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(fpga_region_unregister);
+
+static int of_fpga_region_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct fpga_region *region;
+	struct fpga_manager *mgr;
+	int ret;
+
+	/* Find the FPGA mgr specified by region or parent region. */
+	mgr = of_fpga_region_get_mgr(np);
+	if (IS_ERR(mgr))
+		return -EPROBE_DEFER;
+
+	region = devm_kzalloc(dev, sizeof(*region), GFP_KERNEL);
+	if (!region) {
+		ret = -ENOMEM;
+		goto eprobe_mgr_put;
+	}
+
+	region->mgr = mgr;
+
+	/* Specify how to get bridges for this type of region. */
+	region->get_bridges = of_fpga_region_get_bridges;
+
+	ret = fpga_region_register(dev, region);
+	if (ret)
+		goto eprobe_mgr_put;
+
 	of_platform_populate(np, fpga_region_of_match, NULL, &region->dev);
 
 	dev_info(dev, "FPGA Region probed\n");
 
 	return 0;
 
-err_remove:
-	ida_simple_remove(&fpga_region_ida, id);
-err_kfree:
-	kfree(region);
-err_put_mgr:
+eprobe_mgr_put:
 	fpga_mgr_put(mgr);
-
 	return ret;
 }
 
@@ -586,8 +612,7 @@ static int of_fpga_region_remove(struct platform_device *pdev)
 {
 	struct fpga_region *region = platform_get_drvdata(pdev);
 
-	device_unregister(&region->dev);
-	fpga_mgr_put(region->mgr);
+	fpga_region_unregister(region);
 
 	return 0;
 }
@@ -606,7 +631,6 @@ static void fpga_region_dev_release(struct device *dev)
 	struct fpga_region *region = to_fpga_region(dev);
 
 	ida_simple_remove(&fpga_region_ida, region->dev.id);
-	kfree(region);
 }
 
 /**
diff --git a/include/linux/fpga/fpga-region.h b/include/linux/fpga/fpga-region.h
index f84a2e1..76dda68 100644
--- a/include/linux/fpga/fpga-region.h
+++ b/include/linux/fpga/fpga-region.h
@@ -12,6 +12,8 @@
  * @bridge_list: list of FPGA bridges specified in region
  * @mgr: FPGA manager
  * @info: FPGA image info
+ * @priv: private data
+ * @get_bridges: optional function to get bridges to a list
  */
 struct fpga_region {
 	struct device dev;
@@ -19,10 +21,15 @@ struct fpga_region {
 	struct list_head bridge_list;
 	struct fpga_manager *mgr;
 	struct fpga_image_info *info;
+	void *priv;
+	int (*get_bridges)(struct fpga_region *region);
 };
 
 #define to_fpga_region(d) container_of(d, struct fpga_region, dev)
 
 int fpga_region_program_fpga(struct fpga_region *region);
 
+int fpga_region_register(struct device *dev, struct fpga_region *region);
+int fpga_region_unregister(struct fpga_region *region);
+
 #endif /* _FPGA_REGION_H */
-- 
2.7.4

[PATCH v3 15/16] fpga: region: add fpga_region_class_find

[Alan Tull]

Add a function for searching the fpga-region class.  This
will be useful when device tree code is no longer in the
same file that declares the fpga-region class.  Another
step in separating common FPGA region code from device
tree support.

Signed-off-by: Alan Tull <atull@kernel.org>
Acked-by: Moritz Fischer <mdf@kernel.org>
---
 drivers/fpga/fpga-region.c       | 23 +++++++++++++++--------
 include/linux/fpga/fpga-region.h |  5 ++++-
 2 files changed, 19 insertions(+), 9 deletions(-)

diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index 2e6c47b..4d2a641 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -30,6 +30,20 @@
 static DEFINE_IDA(fpga_region_ida);
 static struct class *fpga_region_class;
 
+struct fpga_region *fpga_region_class_find(
+	struct device *start, const void *data,
+	int (*match)(struct device *, const void *))
+{
+	struct device *dev;
+
+	dev = class_find_device(fpga_region_class, start, data, match);
+	if (!dev)
+		return NULL;
+
+	return to_fpga_region(dev);
+}
+EXPORT_SYMBOL_GPL(fpga_region_class_find);
+
 static const struct of_device_id fpga_region_of_match[] = {
 	{ .compatible = "fpga-region", },
 	{},
@@ -51,14 +65,7 @@ static int fpga_region_of_node_match(struct device *dev, const void *data)
  */
 static struct fpga_region *of_fpga_region_find(struct device_node *np)
 {
-	struct device *dev;
-
-	dev = class_find_device(fpga_region_class, NULL, np,
-				fpga_region_of_node_match);
-	if (!dev)
-		return NULL;
-
-	return to_fpga_region(dev);
+	return fpga_region_class_find(NULL, np, fpga_region_of_node_match);
 }
 
 /**
diff --git a/include/linux/fpga/fpga-region.h b/include/linux/fpga/fpga-region.h
index 76dda68..f2eecdd 100644
--- a/include/linux/fpga/fpga-region.h
+++ b/include/linux/fpga/fpga-region.h
@@ -27,8 +27,11 @@ struct fpga_region {
 
 #define to_fpga_region(d) container_of(d, struct fpga_region, dev)
 
-int fpga_region_program_fpga(struct fpga_region *region);
+struct fpga_region *fpga_region_class_find(
+	struct device *start, const void *data,
+	int (*match)(struct device *, const void *));
 
+int fpga_region_program_fpga(struct fpga_region *region);
 int fpga_region_register(struct device *dev, struct fpga_region *region);
 int fpga_region_unregister(struct fpga_region *region);
 
-- 
2.7.4

[PATCH v3 16/16] fpga: region: move device tree support to of-fpga-region.c

[Alan Tull]

Create of-fpga-region.c and ove the following functions without
modification from fpga-region.c.

* of_fpga_region_find
* of_fpga_region_get_mgr
* of_fpga_region_get_bridges
* child_regions_with_firmware
* of_fpga_region_parse_ov
* of_fpga_region_notify_pre_apply
* of_fpga_region_notify_post_remove
* of_fpga_region_notify
* of_fpga_region_probe
* of_fpga_region_remove

Create two new function with some code from fpga_region_init/exit.

* of_fpga_region_init
* of_fpga_region_exit

Signed-off-by: Alan Tull <atull@kernel.org>
---
 drivers/fpga/Kconfig          |  13 +-
 drivers/fpga/Makefile         |   1 +
 drivers/fpga/fpga-region.c    | 451 +-------------------------------------
 drivers/fpga/of-fpga-region.c | 495 ++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 507 insertions(+), 453 deletions(-)
 create mode 100644 drivers/fpga/of-fpga-region.c

diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
index 161ba9d..394c141 100644
--- a/drivers/fpga/Kconfig
+++ b/drivers/fpga/Kconfig
@@ -15,10 +15,17 @@ if FPGA
 
 config FPGA_REGION
 	tristate "FPGA Region"
-	depends on OF && FPGA_BRIDGE
+	depends on FPGA_BRIDGE
+	help
+	  FPGA Region common code.  A FPGA Region controls a FPGA Manager
+	  and the FPGA Bridges associated with either a reconfigurable
+	  region of an FPGA or a whole FPGA.
+
+config OF_FPGA_REGION
+	tristate "FPGA Region Device Tree Overlay Support"
+	depends on OF && FPGA_REGION
 	help
-	  FPGA Regions allow loading FPGA images under control of
-	  the Device Tree.
+	  Support for loading FPGA images under control of Device Tree.
 
 config FPGA_MGR_ICE40_SPI
 	tristate "Lattice iCE40 SPI"
diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
index 2a4f021..85b45d0 100644
--- a/drivers/fpga/Makefile
+++ b/drivers/fpga/Makefile
@@ -23,3 +23,4 @@ obj-$(CONFIG_XILINX_PR_DECOUPLER)	+= xilinx-pr-decoupler.o
 
 # High Level Interfaces
 obj-$(CONFIG_FPGA_REGION)		+= fpga-region.o
+obj-$(CONFIG_OF_FPGA_REGION)		+= of-fpga-region.o
diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
index 4d2a641..afc6188 100644
--- a/drivers/fpga/fpga-region.c
+++ b/drivers/fpga/fpga-region.c
@@ -2,6 +2,7 @@
  * FPGA Region - Device Tree support for FPGA programming under Linux
  *
  *  Copyright (C) 2013-2016 Altera Corporation
+ *  Copyright (C) 2017 Intel Corporation
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
@@ -23,7 +24,6 @@
 #include <linux/kernel.h>
 #include <linux/list.h>
 #include <linux/module.h>
-#include <linux/of_platform.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 
@@ -44,30 +44,6 @@ struct fpga_region *fpga_region_class_find(
 }
 EXPORT_SYMBOL_GPL(fpga_region_class_find);
 
-static const struct of_device_id fpga_region_of_match[] = {
-	{ .compatible = "fpga-region", },
-	{},
-};
-MODULE_DEVICE_TABLE(of, fpga_region_of_match);
-
-static int fpga_region_of_node_match(struct device *dev, const void *data)
-{
-	return dev->of_node == data;
-}
-
-/**
- * of_fpga_region_find - find FPGA region
- * @np: device node of FPGA Region
- *
- * Caller will need to put_device(&region->dev) when done.
- *
- * Returns FPGA Region struct or NULL
- */
-static struct fpga_region *of_fpga_region_find(struct device_node *np)
-{
-	return fpga_region_class_find(NULL, np, fpga_region_of_node_match);
-}
-
 /**
  * fpga_region_get - get an exclusive reference to a fpga region
  * @region: FPGA Region struct
@@ -116,102 +92,6 @@ static void fpga_region_put(struct fpga_region *region)
 }
 
 /**
- * of_fpga_region_get_mgr - get reference for FPGA manager
- * @np: device node of FPGA region
- *
- * Get FPGA Manager from "fpga-mgr" property or from ancestor region.
- *
- * Caller should call fpga_mgr_put() when done with manager.
- *
- * Return: fpga manager struct or IS_ERR() condition containing error code.
- */
-static struct fpga_manager *of_fpga_region_get_mgr(struct device_node *np)
-{
-	struct device_node  *mgr_node;
-	struct fpga_manager *mgr;
-
-	of_node_get(np);
-	while (np) {
-		if (of_device_is_compatible(np, "fpga-region")) {
-			mgr_node = of_parse_phandle(np, "fpga-mgr", 0);
-			if (mgr_node) {
-				mgr = of_fpga_mgr_get(mgr_node);
-				of_node_put(np);
-				return mgr;
-			}
-		}
-		np = of_get_next_parent(np);
-	}
-	of_node_put(np);
-
-	return ERR_PTR(-EINVAL);
-}
-
-/**
- * of_fpga_region_get_bridges - create a list of bridges
- * @region: FPGA region
- *
- * Create a list of bridges including the parent bridge and the bridges
- * specified by "fpga-bridges" property.  Note that the
- * fpga_bridges_enable/disable/put functions are all fine with an empty list
- * if that happens.
- *
- * Caller should call fpga_bridges_put(&region->bridge_list) when
- * done with the bridges.
- *
- * Return 0 for success (even if there are no bridges specified)
- * or -EBUSY if any of the bridges are in use.
- */
-static int of_fpga_region_get_bridges(struct fpga_region *region)
-{
-	struct device *dev = &region->dev;
-	struct device_node *region_np = dev->of_node;
-	struct fpga_image_info *info = region->info;
-	struct device_node *br, *np, *parent_br = NULL;
-	int i, ret;
-
-	/* If parent is a bridge, add to list */
-	ret = of_fpga_bridge_get_to_list(region_np->parent, info,
-					 &region->bridge_list);
-
-	/* -EBUSY means parent is a bridge that is under use. Give up. */
-	if (ret == -EBUSY)
-		return ret;
-
-	/* Zero return code means parent was a bridge and was added to list. */
-	if (!ret)
-		parent_br = region_np->parent;
-
-	/* If overlay has a list of bridges, use it. */
-	if (of_parse_phandle(info->overlay, "fpga-bridges", 0))
-		np = info->overlay;
-	else
-		np = region_np;
-
-	for (i = 0; ; i++) {
-		br = of_parse_phandle(np, "fpga-bridges", i);
-		if (!br)
-			break;
-
-		/* If parent bridge is in list, skip it. */
-		if (br == parent_br)
-			continue;
-
-		/* If node is a bridge, get it and add to list */
-		ret = of_fpga_bridge_get_to_list(br, info,
-						 &region->bridge_list);
-
-		/* If any of the bridges are in use, give up */
-		if (ret == -EBUSY) {
-			fpga_bridges_put(&region->bridge_list);
-			return -EBUSY;
-		}
-	}
-
-	return 0;
-}
-
-/**
  * fpga_region_program_fpga - program FPGA
  * @region: FPGA region
  * Program an FPGA using fpga image info (region->info).
@@ -282,259 +162,6 @@ int fpga_region_program_fpga(struct fpga_region *region)
 }
 EXPORT_SYMBOL_GPL(fpga_region_program_fpga);
 
-/**
- * child_regions_with_firmware
- * @overlay: device node of the overlay
- *
- * If the overlay adds child FPGA regions, they are not allowed to have
- * firmware-name property.
- *
- * Return 0 for OK or -EINVAL if child FPGA region adds firmware-name.
- */
-static int child_regions_with_firmware(struct device_node *overlay)
-{
-	struct device_node *child_region;
-	const char *child_firmware_name;
-	int ret = 0;
-
-	of_node_get(overlay);
-
-	child_region = of_find_matching_node(overlay, fpga_region_of_match);
-	while (child_region) {
-		if (!of_property_read_string(child_region, "firmware-name",
-					     &child_firmware_name)) {
-			ret = -EINVAL;
-			break;
-		}
-		child_region = of_find_matching_node(child_region,
-						     fpga_region_of_match);
-	}
-
-	of_node_put(child_region);
-
-	if (ret)
-		pr_err("firmware-name not allowed in child FPGA region: %s",
-		       child_region->full_name);
-
-	return ret;
-}
-
-/**
- * of_fpga_region_parse_ov - parse and check overlay applied to region
- *
- * @region: FPGA region
- * @overlay: overlay applied to the FPGA region
- *
- * Given an overlay applied to a FPGA region, parse the FPGA image specific
- * info in the overlay and do some checking.
- *
- * Returns:
- *   NULL if overlay doesn't direct us to program the FPGA.
- *   fpga_image_info struct if there is an image to program.
- *   error code for invalid overlay.
- */
-static struct fpga_image_info *of_fpga_region_parse_ov(
-						struct fpga_region *region,
-						struct device_node *overlay)
-{
-	struct device *dev = &region->dev;
-	struct fpga_image_info *info;
-	const char *firmware_name;
-	int ret;
-
-	if (region->info) {
-		dev_err(dev, "Region already has overlay applied.\n");
-		return ERR_PTR(-EINVAL);
-	}
-
-	/*
-	 * Reject overlay if child FPGA Regions added in the overlay have
-	 * firmware-name property (would mean that an FPGA region that has
-	 * not been added to the live tree yet is doing FPGA programming).
-	 */
-	ret = child_regions_with_firmware(overlay);
-	if (ret)
-		return ERR_PTR(ret);
-
-	info = fpga_image_info_alloc(dev);
-	if (!info)
-		return ERR_PTR(-ENOMEM);
-
-	info->overlay = overlay;
-
-	/* Read FPGA region properties from the overlay */
-	if (of_property_read_bool(overlay, "partial-fpga-config"))
-		info->flags |= FPGA_MGR_PARTIAL_RECONFIG;
-
-	if (of_property_read_bool(overlay, "external-fpga-config"))
-		info->flags |= FPGA_MGR_EXTERNAL_CONFIG;
-
-	if (of_property_read_bool(overlay, "encrypted-fpga-config"))
-		info->flags |= FPGA_MGR_ENCRYPTED_BITSTREAM;
-
-	if (!of_property_read_string(overlay, "firmware-name",
-				     &firmware_name)) {
-		info->firmware_name = devm_kstrdup(dev, firmware_name,
-						   GFP_KERNEL);
-		if (!info->firmware_name)
-			return ERR_PTR(-ENOMEM);
-	}
-
-	of_property_read_u32(overlay, "region-unfreeze-timeout-us",
-			     &info->enable_timeout_us);
-
-	of_property_read_u32(overlay, "region-freeze-timeout-us",
-			     &info->disable_timeout_us);
-
-	of_property_read_u32(overlay, "config-complete-timeout-us",
-			     &info->config_complete_timeout_us);
-
-	/* If overlay is not programming the FPGA, don't need FPGA image info */
-	if (!info->firmware_name) {
-		ret = 0;
-		goto ret_no_info;
-	}
-
-	/*
-	 * If overlay informs us FPGA was externally programmed, specifying
-	 * firmware here would be ambiguous.
-	 */
-	if (info->flags & FPGA_MGR_EXTERNAL_CONFIG) {
-		dev_err(dev, "error: specified firmware and external-fpga-config");
-		ret = -EINVAL;
-		goto ret_no_info;
-	}
-
-	return info;
-ret_no_info:
-	fpga_image_info_free(dev, info);
-	return ERR_PTR(ret);
-}
-
-/**
- * of_fpga_region_notify_pre_apply - pre-apply overlay notification
- *
- * @region: FPGA region that the overlay was applied to
- * @nd: overlay notification data
- *
- * Called when an overlay targeted to a FPGA Region is about to be applied.
- * Parses the overlay for properties that influence how the FPGA will be
- * programmed and does some checking. If the checks pass, programs the FPGA.
- * If the checks fail, overlay is rejected and does not get added to the
- * live tree.
- *
- * Returns 0 for success or negative error code for failure.
- */
-static int of_fpga_region_notify_pre_apply(struct fpga_region *region,
-					   struct of_overlay_notify_data *nd)
-{
-	struct device *dev = &region->dev;
-	struct fpga_image_info *info;
-	int ret;
-
-	if (region->info) {
-		dev_err(dev, "Region already has overlay applied.\n");
-		return -EINVAL;
-	}
-
-	info = of_fpga_region_parse_ov(region, nd->overlay);
-	if (IS_ERR(info))
-		return PTR_ERR(info);
-
-	if (!info)
-		return 0;
-
-	region->info = info;
-	ret = fpga_region_program_fpga(region);
-	if (ret) {
-		/* error; reject overlay */
-		fpga_image_info_free(dev, info);
-		region->info = NULL;
-	}
-
-	return ret;
-}
-
-/**
- * of_fpga_region_notify_post_remove - post-remove overlay notification
- *
- * @region: FPGA region that was targeted by the overlay that was removed
- * @nd: overlay notification data
- *
- * Called after an overlay has been removed if the overlay's target was a
- * FPGA region.
- */
-static void of_fpga_region_notify_post_remove(struct fpga_region *region,
-					      struct of_overlay_notify_data *nd)
-{
-	fpga_bridges_disable(&region->bridge_list);
-	fpga_bridges_put(&region->bridge_list);
-	fpga_image_info_free(&region->dev, region->info);
-	region->info = NULL;
-}
-
-/**
- * of_fpga_region_notify - reconfig notifier for dynamic DT changes
- * @nb:		notifier block
- * @action:	notifier action
- * @arg:	reconfig data
- *
- * This notifier handles programming a FPGA when a "firmware-name" property is
- * added to a fpga-region.
- *
- * Returns NOTIFY_OK or error if FPGA programming fails.
- */
-static int of_fpga_region_notify(struct notifier_block *nb,
-				 unsigned long action, void *arg)
-{
-	struct of_overlay_notify_data *nd = arg;
-	struct fpga_region *region;
-	int ret;
-
-	switch (action) {
-	case OF_OVERLAY_PRE_APPLY:
-		pr_debug("%s OF_OVERLAY_PRE_APPLY\n", __func__);
-		break;
-	case OF_OVERLAY_POST_APPLY:
-		pr_debug("%s OF_OVERLAY_POST_APPLY\n", __func__);
-		return NOTIFY_OK;       /* not for us */
-	case OF_OVERLAY_PRE_REMOVE:
-		pr_debug("%s OF_OVERLAY_PRE_REMOVE\n", __func__);
-		return NOTIFY_OK;       /* not for us */
-	case OF_OVERLAY_POST_REMOVE:
-		pr_debug("%s OF_OVERLAY_POST_REMOVE\n", __func__);
-		break;
-	default:			/* should not happen */
-		return NOTIFY_OK;
-	}
-
-	region = of_fpga_region_find(nd->target);
-	if (!region)
-		return NOTIFY_OK;
-
-	ret = 0;
-	switch (action) {
-	case OF_OVERLAY_PRE_APPLY:
-		ret = of_fpga_region_notify_pre_apply(region, nd);
-		break;
-
-	case OF_OVERLAY_POST_REMOVE:
-		of_fpga_region_notify_post_remove(region, nd);
-		break;
-	}
-
-	put_device(&region->dev);
-
-	if (ret)
-		return notifier_from_errno(ret);
-
-	return NOTIFY_OK;
-}
-
-static struct notifier_block fpga_region_of_nb = {
-	.notifier_call = of_fpga_region_notify,
-};
-
 int fpga_region_register(struct device *dev, struct fpga_region *region)
 {
 	int id, ret = 0;
@@ -576,63 +203,6 @@ int fpga_region_unregister(struct fpga_region *region)
 }
 EXPORT_SYMBOL_GPL(fpga_region_unregister);
 
-static int of_fpga_region_probe(struct platform_device *pdev)
-{
-	struct device *dev = &pdev->dev;
-	struct device_node *np = dev->of_node;
-	struct fpga_region *region;
-	struct fpga_manager *mgr;
-	int ret;
-
-	/* Find the FPGA mgr specified by region or parent region. */
-	mgr = of_fpga_region_get_mgr(np);
-	if (IS_ERR(mgr))
-		return -EPROBE_DEFER;
-
-	region = devm_kzalloc(dev, sizeof(*region), GFP_KERNEL);
-	if (!region) {
-		ret = -ENOMEM;
-		goto eprobe_mgr_put;
-	}
-
-	region->mgr = mgr;
-
-	/* Specify how to get bridges for this type of region. */
-	region->get_bridges = of_fpga_region_get_bridges;
-
-	ret = fpga_region_register(dev, region);
-	if (ret)
-		goto eprobe_mgr_put;
-
-	of_platform_populate(np, fpga_region_of_match, NULL, &region->dev);
-
-	dev_info(dev, "FPGA Region probed\n");
-
-	return 0;
-
-eprobe_mgr_put:
-	fpga_mgr_put(mgr);
-	return ret;
-}
-
-static int of_fpga_region_remove(struct platform_device *pdev)
-{
-	struct fpga_region *region = platform_get_drvdata(pdev);
-
-	fpga_region_unregister(region);
-
-	return 0;
-}
-
-static struct platform_driver of_fpga_region_driver = {
-	.probe = of_fpga_region_probe,
-	.remove = of_fpga_region_remove,
-	.driver = {
-		.name	= "fpga-region",
-		.of_match_table = of_match_ptr(fpga_region_of_match),
-	},
-};
-
 static void fpga_region_dev_release(struct device *dev)
 {
 	struct fpga_region *region = to_fpga_region(dev);
@@ -646,36 +216,17 @@ static void fpga_region_dev_release(struct device *dev)
  */
 static int __init fpga_region_init(void)
 {
-	int ret;
-
 	fpga_region_class = class_create(THIS_MODULE, "fpga_region");
 	if (IS_ERR(fpga_region_class))
 		return PTR_ERR(fpga_region_class);
 
 	fpga_region_class->dev_release = fpga_region_dev_release;
 
-	ret = of_overlay_notifier_register(&fpga_region_of_nb);
-	if (ret)
-		goto err_class;
-
-	ret = platform_driver_register(&of_fpga_region_driver);
-	if (ret)
-		goto err_plat;
-
 	return 0;
-
-err_plat:
-	of_overlay_notifier_unregister(&fpga_region_of_nb);
-err_class:
-	class_destroy(fpga_region_class);
-	ida_destroy(&fpga_region_ida);
-	return ret;
 }
 
 static void __exit fpga_region_exit(void)
 {
-	platform_driver_unregister(&of_fpga_region_driver);
-	of_overlay_notifier_unregister(&fpga_region_of_nb);
 	class_destroy(fpga_region_class);
 	ida_destroy(&fpga_region_ida);
 }
diff --git a/drivers/fpga/of-fpga-region.c b/drivers/fpga/of-fpga-region.c
new file mode 100644
index 0000000..c2ea9b6
--- /dev/null
+++ b/drivers/fpga/of-fpga-region.c
@@ -0,0 +1,495 @@
+/*
+ * FPGA Region - Device Tree support for FPGA programming under Linux
+ *
+ *  Copyright (C) 2013-2016 Altera Corporation
+ *  Copyright (C) 2017 Intel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/fpga/fpga-bridge.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/fpga/fpga-region.h>
+#include <linux/idr.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+static const struct of_device_id fpga_region_of_match[] = {
+	{ .compatible = "fpga-region", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, fpga_region_of_match);
+
+static int fpga_region_of_node_match(struct device *dev, const void *data)
+{
+	return dev->of_node == data;
+}
+
+/**
+ * of_fpga_region_find - find FPGA region
+ * @np: device node of FPGA Region
+ *
+ * Caller will need to put_device(&region->dev) when done.
+ *
+ * Returns FPGA Region struct or NULL
+ */
+static struct fpga_region *of_fpga_region_find(struct device_node *np)
+{
+	return fpga_region_class_find(NULL, np, fpga_region_of_node_match);
+}
+
+/**
+ * of_fpga_region_get_mgr - get reference for FPGA manager
+ * @np: device node of FPGA region
+ *
+ * Get FPGA Manager from "fpga-mgr" property or from ancestor region.
+ *
+ * Caller should call fpga_mgr_put() when done with manager.
+ *
+ * Return: fpga manager struct or IS_ERR() condition containing error code.
+ */
+static struct fpga_manager *of_fpga_region_get_mgr(struct device_node *np)
+{
+	struct device_node  *mgr_node;
+	struct fpga_manager *mgr;
+
+	of_node_get(np);
+	while (np) {
+		if (of_device_is_compatible(np, "fpga-region")) {
+			mgr_node = of_parse_phandle(np, "fpga-mgr", 0);
+			if (mgr_node) {
+				mgr = of_fpga_mgr_get(mgr_node);
+				of_node_put(np);
+				return mgr;
+			}
+		}
+		np = of_get_next_parent(np);
+	}
+	of_node_put(np);
+
+	return ERR_PTR(-EINVAL);
+}
+
+/**
+ * of_fpga_region_get_bridges - create a list of bridges
+ * @region: FPGA region
+ *
+ * Create a list of bridges including the parent bridge and the bridges
+ * specified by "fpga-bridges" property.  Note that the
+ * fpga_bridges_enable/disable/put functions are all fine with an empty list
+ * if that happens.
+ *
+ * Caller should call fpga_bridges_put(&region->bridge_list) when
+ * done with the bridges.
+ *
+ * Return 0 for success (even if there are no bridges specified)
+ * or -EBUSY if any of the bridges are in use.
+ */
+static int of_fpga_region_get_bridges(struct fpga_region *region)
+{
+	struct device *dev = &region->dev;
+	struct device_node *region_np = dev->of_node;
+	struct fpga_image_info *info = region->info;
+	struct device_node *br, *np, *parent_br = NULL;
+	int i, ret;
+
+	/* If parent is a bridge, add to list */
+	ret = of_fpga_bridge_get_to_list(region_np->parent, info,
+					 &region->bridge_list);
+
+	/* -EBUSY means parent is a bridge that is under use. Give up. */
+	if (ret == -EBUSY)
+		return ret;
+
+	/* Zero return code means parent was a bridge and was added to list. */
+	if (!ret)
+		parent_br = region_np->parent;
+
+	/* If overlay has a list of bridges, use it. */
+	if (of_parse_phandle(info->overlay, "fpga-bridges", 0))
+		np = info->overlay;
+	else
+		np = region_np;
+
+	for (i = 0; ; i++) {
+		br = of_parse_phandle(np, "fpga-bridges", i);
+		if (!br)
+			break;
+
+		/* If parent bridge is in list, skip it. */
+		if (br == parent_br)
+			continue;
+
+		/* If node is a bridge, get it and add to list */
+		ret = of_fpga_bridge_get_to_list(br, info,
+						 &region->bridge_list);
+
+		/* If any of the bridges are in use, give up */
+		if (ret == -EBUSY) {
+			fpga_bridges_put(&region->bridge_list);
+			return -EBUSY;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * child_regions_with_firmware
+ * @overlay: device node of the overlay
+ *
+ * If the overlay adds child FPGA regions, they are not allowed to have
+ * firmware-name property.
+ *
+ * Return 0 for OK or -EINVAL if child FPGA region adds firmware-name.
+ */
+static int child_regions_with_firmware(struct device_node *overlay)
+{
+	struct device_node *child_region;
+	const char *child_firmware_name;
+	int ret = 0;
+
+	of_node_get(overlay);
+
+	child_region = of_find_matching_node(overlay, fpga_region_of_match);
+	while (child_region) {
+		if (!of_property_read_string(child_region, "firmware-name",
+					     &child_firmware_name)) {
+			ret = -EINVAL;
+			break;
+		}
+		child_region = of_find_matching_node(child_region,
+						     fpga_region_of_match);
+	}
+
+	of_node_put(child_region);
+
+	if (ret)
+		pr_err("firmware-name not allowed in child FPGA region: %s",
+		       child_region->full_name);
+
+	return ret;
+}
+
+/**
+ * of_fpga_region_parse_ov - parse and check overlay applied to region
+ *
+ * @region: FPGA region
+ * @overlay: overlay applied to the FPGA region
+ *
+ * Given an overlay applied to a FPGA region, parse the FPGA image specific
+ * info in the overlay and do some checking.
+ *
+ * Returns:
+ *   NULL if overlay doesn't direct us to program the FPGA.
+ *   fpga_image_info struct if there is an image to program.
+ *   error code for invalid overlay.
+ */
+static struct fpga_image_info *of_fpga_region_parse_ov(
+						struct fpga_region *region,
+						struct device_node *overlay)
+{
+	struct device *dev = &region->dev;
+	struct fpga_image_info *info;
+	const char *firmware_name;
+	int ret;
+
+	if (region->info) {
+		dev_err(dev, "Region already has overlay applied.\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	/*
+	 * Reject overlay if child FPGA Regions added in the overlay have
+	 * firmware-name property (would mean that an FPGA region that has
+	 * not been added to the live tree yet is doing FPGA programming).
+	 */
+	ret = child_regions_with_firmware(overlay);
+	if (ret)
+		return ERR_PTR(ret);
+
+	info = fpga_image_info_alloc(dev);
+	if (!info)
+		return ERR_PTR(-ENOMEM);
+
+	info->overlay = overlay;
+
+	/* Read FPGA region properties from the overlay */
+	if (of_property_read_bool(overlay, "partial-fpga-config"))
+		info->flags |= FPGA_MGR_PARTIAL_RECONFIG;
+
+	if (of_property_read_bool(overlay, "external-fpga-config"))
+		info->flags |= FPGA_MGR_EXTERNAL_CONFIG;
+
+	if (of_property_read_bool(overlay, "encrypted-fpga-config"))
+		info->flags |= FPGA_MGR_ENCRYPTED_BITSTREAM;
+
+	if (!of_property_read_string(overlay, "firmware-name",
+				     &firmware_name)) {
+		info->firmware_name = devm_kstrdup(dev, firmware_name,
+						   GFP_KERNEL);
+		if (!info->firmware_name)
+			return ERR_PTR(-ENOMEM);
+	}
+
+	of_property_read_u32(overlay, "region-unfreeze-timeout-us",
+			     &info->enable_timeout_us);
+
+	of_property_read_u32(overlay, "region-freeze-timeout-us",
+			     &info->disable_timeout_us);
+
+	of_property_read_u32(overlay, "config-complete-timeout-us",
+			     &info->config_complete_timeout_us);
+
+	/* If overlay is not programming the FPGA, don't need FPGA image info */
+	if (!info->firmware_name) {
+		ret = 0;
+		goto ret_no_info;
+	}
+
+	/*
+	 * If overlay informs us FPGA was externally programmed, specifying
+	 * firmware here would be ambiguous.
+	 */
+	if (info->flags & FPGA_MGR_EXTERNAL_CONFIG) {
+		dev_err(dev, "error: specified firmware and external-fpga-config");
+		ret = -EINVAL;
+		goto ret_no_info;
+	}
+
+	return info;
+ret_no_info:
+	fpga_image_info_free(dev, info);
+	return ERR_PTR(ret);
+}
+
+/**
+ * of_fpga_region_notify_pre_apply - pre-apply overlay notification
+ *
+ * @region: FPGA region that the overlay was applied to
+ * @nd: overlay notification data
+ *
+ * Called when an overlay targeted to a FPGA Region is about to be applied.
+ * Parses the overlay for properties that influence how the FPGA will be
+ * programmed and does some checking. If the checks pass, programs the FPGA.
+ * If the checks fail, overlay is rejected and does not get added to the
+ * live tree.
+ *
+ * Returns 0 for success or negative error code for failure.
+ */
+static int of_fpga_region_notify_pre_apply(struct fpga_region *region,
+					   struct of_overlay_notify_data *nd)
+{
+	struct device *dev = &region->dev;
+	struct fpga_image_info *info;
+	int ret;
+
+	if (region->info) {
+		dev_err(dev, "Region already has overlay applied.\n");
+		return -EINVAL;
+	}
+
+	info = of_fpga_region_parse_ov(region, nd->overlay);
+	if (IS_ERR(info))
+		return PTR_ERR(info);
+
+	if (!info)
+		return 0;
+
+	region->info = info;
+	ret = fpga_region_program_fpga(region);
+	if (ret) {
+		/* error; reject overlay */
+		fpga_image_info_free(dev, info);
+		region->info = NULL;
+	}
+
+	return ret;
+}
+
+/**
+ * of_fpga_region_notify_post_remove - post-remove overlay notification
+ *
+ * @region: FPGA region that was targeted by the overlay that was removed
+ * @nd: overlay notification data
+ *
+ * Called after an overlay has been removed if the overlay's target was a
+ * FPGA region.
+ */
+static void of_fpga_region_notify_post_remove(struct fpga_region *region,
+					      struct of_overlay_notify_data *nd)
+{
+	fpga_bridges_disable(&region->bridge_list);
+	fpga_bridges_put(&region->bridge_list);
+	fpga_image_info_free(&region->dev, region->info);
+	region->info = NULL;
+}
+
+/**
+ * of_fpga_region_notify - reconfig notifier for dynamic DT changes
+ * @nb:		notifier block
+ * @action:	notifier action
+ * @arg:	reconfig data
+ *
+ * This notifier handles programming a FPGA when a "firmware-name" property is
+ * added to a fpga-region.
+ *
+ * Returns NOTIFY_OK or error if FPGA programming fails.
+ */
+static int of_fpga_region_notify(struct notifier_block *nb,
+				 unsigned long action, void *arg)
+{
+	struct of_overlay_notify_data *nd = arg;
+	struct fpga_region *region;
+	int ret;
+
+	switch (action) {
+	case OF_OVERLAY_PRE_APPLY:
+		pr_debug("%s OF_OVERLAY_PRE_APPLY\n", __func__);
+		break;
+	case OF_OVERLAY_POST_APPLY:
+		pr_debug("%s OF_OVERLAY_POST_APPLY\n", __func__);
+		return NOTIFY_OK;       /* not for us */
+	case OF_OVERLAY_PRE_REMOVE:
+		pr_debug("%s OF_OVERLAY_PRE_REMOVE\n", __func__);
+		return NOTIFY_OK;       /* not for us */
+	case OF_OVERLAY_POST_REMOVE:
+		pr_debug("%s OF_OVERLAY_POST_REMOVE\n", __func__);
+		break;
+	default:			/* should not happen */
+		return NOTIFY_OK;
+	}
+
+	region = of_fpga_region_find(nd->target);
+	if (!region)
+		return NOTIFY_OK;
+
+	ret = 0;
+	switch (action) {
+	case OF_OVERLAY_PRE_APPLY:
+		ret = of_fpga_region_notify_pre_apply(region, nd);
+		break;
+
+	case OF_OVERLAY_POST_REMOVE:
+		of_fpga_region_notify_post_remove(region, nd);
+		break;
+	}
+
+	put_device(&region->dev);
+
+	if (ret)
+		return notifier_from_errno(ret);
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block fpga_region_of_nb = {
+	.notifier_call = of_fpga_region_notify,
+};
+
+static int of_fpga_region_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct fpga_region *region;
+	struct fpga_manager *mgr;
+	int ret;
+
+	/* Find the FPGA mgr specified by region or parent region. */
+	mgr = of_fpga_region_get_mgr(np);
+	if (IS_ERR(mgr))
+		return -EPROBE_DEFER;
+
+	region = devm_kzalloc(dev, sizeof(*region), GFP_KERNEL);
+	if (!region) {
+		ret = -ENOMEM;
+		goto eprobe_mgr_put;
+	}
+
+	region->mgr = mgr;
+
+	/* Specify how to get bridges for this type of region. */
+	region->get_bridges = of_fpga_region_get_bridges;
+
+	ret = fpga_region_register(dev, region);
+	if (ret)
+		goto eprobe_mgr_put;
+
+	of_platform_populate(np, fpga_region_of_match, NULL, &region->dev);
+
+	dev_info(dev, "FPGA Region probed\n");
+
+	return 0;
+
+eprobe_mgr_put:
+	fpga_mgr_put(mgr);
+	return ret;
+}
+
+static int of_fpga_region_remove(struct platform_device *pdev)
+{
+	struct fpga_region *region = platform_get_drvdata(pdev);
+
+	fpga_region_unregister(region);
+
+	return 0;
+}
+
+static struct platform_driver of_fpga_region_driver = {
+	.probe = of_fpga_region_probe,
+	.remove = of_fpga_region_remove,
+	.driver = {
+		.name	= "of-fpga-region",
+		.of_match_table = of_match_ptr(fpga_region_of_match),
+	},
+};
+
+/**
+ * fpga_region_init - init function for fpga_region class
+ * Creates the fpga_region class and registers a reconfig notifier.
+ */
+static int __init of_fpga_region_init(void)
+{
+	int ret;
+
+	ret = of_overlay_notifier_register(&fpga_region_of_nb);
+	if (ret)
+		return ret;
+
+	ret = platform_driver_register(&of_fpga_region_driver);
+	if (ret)
+		goto err_plat;
+
+	return 0;
+
+err_plat:
+	of_overlay_notifier_unregister(&fpga_region_of_nb);
+	return ret;
+}
+
+static void __exit of_fpga_region_exit(void)
+{
+	platform_driver_unregister(&of_fpga_region_driver);
+	of_overlay_notifier_unregister(&fpga_region_of_nb);
+}
+
+subsys_initcall(of_fpga_region_init);
+module_exit(of_fpga_region_exit);
+
+MODULE_DESCRIPTION("FPGA Region");
+MODULE_AUTHOR("Alan Tull <atull@kernel.org>");
+MODULE_LICENSE("GPL v2");
-- 
2.7.4

Re: [PATCH v3 03/16] fpga: mgr: API change to replace fpga load functions with single function

[Moritz Fischer]

Hi Alan,

On Thu, Jul 6, 2017 at 11:47 AM, Alan Tull <atull@kernel.org> wrote:
> fpga-mgr has three methods for programming FPGAs, depending on
> whether the image is in a scatter gather list, a contiguous
> buffer, or a firmware file. This makes it difficult to write
> upper layers as the caller has to assume whether the FPGA image
> is in a sg table, as a single buffer, or a firmware file.
> This commit moves these parameters to struct fpga_image_info
> and adds a single function for programming fpgas.
>
> New functions:
> * fpga_mgr_load - given fpga manager and struct fpga_image_info,
>    program the fpga.
>
> * fpga_image_info_alloc - alloc a struct fpga_image_info.
>
> * fpga_image_info_free - free a struct fpga_image_info.
>
> These three functions are unexported:
> * fpga_mgr_buf_load_sg
> * fpga_mgr_buf_load
> * fpga_mgr_firmware_load
>
> Also use devm_kstrdup to copy firmware_name so we aren't making
> assumptions about where it comes from when allocing/freeing the
> struct fpga_image_info.
>
> Signed-off-by: Alan Tull <atull@kernel.org>
> ---
>  drivers/fpga/fpga-mgr.c       | 59 +++++++++++++++++++++++++++++++++++--------
>  drivers/fpga/fpga-region.c    | 43 ++++++++++++++++++++-----------
>  include/linux/fpga/fpga-mgr.h | 22 ++++++++++------
>  3 files changed, 90 insertions(+), 34 deletions(-)
>
> diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
> index 188ffef..3478aab 100644
> --- a/drivers/fpga/fpga-mgr.c
> +++ b/drivers/fpga/fpga-mgr.c
> @@ -2,6 +2,7 @@
>   * FPGA Manager Core
>   *
>   *  Copyright (C) 2013-2015 Altera Corporation
> + *  Copyright (C) 2017 Intel Corporation
>   *
>   * With code from the mailing list:
>   * Copyright (C) 2013 Xilinx, Inc.
> @@ -31,6 +32,31 @@
>  static DEFINE_IDA(fpga_mgr_ida);
>  static struct class *fpga_mgr_class;
>
> +struct fpga_image_info *fpga_image_info_alloc(struct device *dev)
> +{
> +       struct fpga_image_info *info;
> +
> +       info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
> +       if (!info)
> +               return ERR_PTR(-ENOMEM);

Doesn't this make it more complex? If in the end you'll anyway have to check
if IS_ERR_OR_NULL()? As opposed to just checking if (!info) on the returned
value.

Just a thought.

> +
> +       return info;
> +}
> +EXPORT_SYMBOL_GPL(fpga_image_info_alloc);
> +
> +void fpga_image_info_free(struct device *dev,
> +                         struct fpga_image_info *info)
> +{
> +       if (!info)
> +               return;
> +
> +       if (info->firmware_name)
> +               devm_kfree(dev, info->firmware_name);
> +
> +       devm_kfree(dev, info);
> +}
> +EXPORT_SYMBOL_GPL(fpga_image_info_free);
> +
>  /*
>   * Call the low level driver's write_init function.  This will do the
>   * device-specific things to get the FPGA into the state where it is ready to
> @@ -137,8 +163,9 @@ static int fpga_mgr_write_complete(struct fpga_manager *mgr,
>   *
>   * Return: 0 on success, negative error code otherwise.
>   */
> -int fpga_mgr_buf_load_sg(struct fpga_manager *mgr, struct fpga_image_info *info,
> -                        struct sg_table *sgt)
> +static int fpga_mgr_buf_load_sg(struct fpga_manager *mgr,
> +                               struct fpga_image_info *info,
> +                               struct sg_table *sgt)
>  {
>         int ret;
>
> @@ -170,7 +197,6 @@ int fpga_mgr_buf_load_sg(struct fpga_manager *mgr, struct fpga_image_info *info,
>
>         return fpga_mgr_write_complete(mgr, info);
>  }
> -EXPORT_SYMBOL_GPL(fpga_mgr_buf_load_sg);
>
>  static int fpga_mgr_buf_load_mapped(struct fpga_manager *mgr,
>                                     struct fpga_image_info *info,
> @@ -210,8 +236,9 @@ static int fpga_mgr_buf_load_mapped(struct fpga_manager *mgr,
>   *
>   * Return: 0 on success, negative error code otherwise.
>   */
> -int fpga_mgr_buf_load(struct fpga_manager *mgr, struct fpga_image_info *info,
> -                     const char *buf, size_t count)
> +static int fpga_mgr_buf_load(struct fpga_manager *mgr,
> +                            struct fpga_image_info *info,
> +                            const char *buf, size_t count)
>  {
>         struct page **pages;
>         struct sg_table sgt;
> @@ -266,7 +293,6 @@ int fpga_mgr_buf_load(struct fpga_manager *mgr, struct fpga_image_info *info,
>
>         return rc;
>  }
> -EXPORT_SYMBOL_GPL(fpga_mgr_buf_load);
>
>  /**
>   * fpga_mgr_firmware_load - request firmware and load to fpga
> @@ -282,9 +308,9 @@ EXPORT_SYMBOL_GPL(fpga_mgr_buf_load);
>   *
>   * Return: 0 on success, negative error code otherwise.
>   */
> -int fpga_mgr_firmware_load(struct fpga_manager *mgr,
> -                          struct fpga_image_info *info,
> -                          const char *image_name)
> +static int fpga_mgr_firmware_load(struct fpga_manager *mgr,
> +                                 struct fpga_image_info *info,
> +                                 const char *image_name)
>  {
>         struct device *dev = &mgr->dev;
>         const struct firmware *fw;
> @@ -307,7 +333,18 @@ int fpga_mgr_firmware_load(struct fpga_manager *mgr,
>
>         return ret;
>  }
> -EXPORT_SYMBOL_GPL(fpga_mgr_firmware_load);
> +
> +int fpga_mgr_load(struct fpga_manager *mgr, struct fpga_image_info *info)
> +{
> +       if (info->sgt)
> +               return fpga_mgr_buf_load_sg(mgr, info, info->sgt);
> +       if (info->buf && info->count)
> +               return fpga_mgr_buf_load(mgr, info, info->buf, info->count);
> +       if (info->firmware_name)
> +               return fpga_mgr_firmware_load(mgr, info, info->firmware_name);
> +       return -EINVAL;
> +}
> +EXPORT_SYMBOL_GPL(fpga_mgr_load);
>
>  static const char * const state_str[] = {
>         [FPGA_MGR_STATE_UNKNOWN] =              "unknown",
> @@ -578,7 +615,7 @@ static void __exit fpga_mgr_class_exit(void)
>         ida_destroy(&fpga_mgr_ida);
>  }
>
> -MODULE_AUTHOR("Alan Tull <atull@opensource.altera.com>");
> +MODULE_AUTHOR("Alan Tull <atull@kernel.org>");
>  MODULE_DESCRIPTION("FPGA manager framework");
>  MODULE_LICENSE("GPL v2");
>
> diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
> index 655940f..c71c9cb 100644
> --- a/drivers/fpga/fpga-region.c
> +++ b/drivers/fpga/fpga-region.c
> @@ -226,14 +226,11 @@ static int fpga_region_get_bridges(struct fpga_region *region,
>  /**
>   * fpga_region_program_fpga - program FPGA
>   * @region: FPGA region
> - * @firmware_name: name of FPGA image firmware file
>   * @overlay: device node of the overlay
> - * Program an FPGA using information in the device tree.
> - * Function assumes that there is a firmware-name property.
> + * Program an FPGA using information in the region's fpga image info.
>   * Return 0 for success or negative error code.
>   */
>  static int fpga_region_program_fpga(struct fpga_region *region,
> -                                   const char *firmware_name,
>                                     struct device_node *overlay)
>  {
>         struct fpga_manager *mgr;
> @@ -264,7 +261,7 @@ static int fpga_region_program_fpga(struct fpga_region *region,
>                 goto err_put_br;
>         }
>
> -       ret = fpga_mgr_firmware_load(mgr, region->info, firmware_name);
> +       ret = fpga_mgr_load(mgr, region->info);
>         if (ret) {
>                 pr_err("failed to load fpga image\n");
>                 goto err_put_br;
> @@ -357,16 +354,15 @@ static int child_regions_with_firmware(struct device_node *overlay)
>  static int fpga_region_notify_pre_apply(struct fpga_region *region,
>                                         struct of_overlay_notify_data *nd)
>  {
> -       const char *firmware_name = NULL;
> +       struct device *dev = &region->dev;
>         struct fpga_image_info *info;
> +       const char *firmware_name;
>         int ret;
>
> -       info = devm_kzalloc(&region->dev, sizeof(*info), GFP_KERNEL);
> +       info = fpga_image_info_alloc(dev);
>         if (!info)
>                 return -ENOMEM;

Can't you return PTR_ERR(info) here (If you don't follow my suggestion above),
or keep it the same here and follow my suggestion ;-)
>
> -       region->info = info;
> -
>         /* Reject overlay if child FPGA Regions have firmware-name property */
>         ret = child_regions_with_firmware(nd->overlay);
>         if (ret)
> @@ -382,7 +378,13 @@ static int fpga_region_notify_pre_apply(struct fpga_region *region,
>         if (of_property_read_bool(nd->overlay, "encrypted-fpga-config"))
>                 info->flags |= FPGA_MGR_ENCRYPTED_BITSTREAM;
>
> -       of_property_read_string(nd->overlay, "firmware-name", &firmware_name);
> +       if (!of_property_read_string(nd->overlay, "firmware-name",
> +                                    &firmware_name)) {
> +               info->firmware_name = devm_kstrdup(dev, firmware_name,
> +                                                  GFP_KERNEL);
> +               if (!info->firmware_name)
> +                       return -ENOMEM;
> +       }
>
>         of_property_read_u32(nd->overlay, "region-unfreeze-timeout-us",
>                              &info->enable_timeout_us);
> @@ -394,22 +396,33 @@ static int fpga_region_notify_pre_apply(struct fpga_region *region,
>                              &info->config_complete_timeout_us);
>
>         /* If FPGA was externally programmed, don't specify firmware */
> -       if ((info->flags & FPGA_MGR_EXTERNAL_CONFIG) && firmware_name) {
> +       if ((info->flags & FPGA_MGR_EXTERNAL_CONFIG) && info->firmware_name) {
>                 pr_err("error: specified firmware and external-fpga-config");
> +               fpga_image_info_free(dev, info);
>                 return -EINVAL;
>         }
>
>         /* FPGA is already configured externally.  We're done. */
> -       if (info->flags & FPGA_MGR_EXTERNAL_CONFIG)
> +       if (info->flags & FPGA_MGR_EXTERNAL_CONFIG) {
> +               fpga_image_info_free(dev, info);
>                 return 0;
> +       }
>
>         /* If we got this far, we should be programming the FPGA */
> -       if (!firmware_name) {
> +       if (!info->firmware_name) {
>                 pr_err("should specify firmware-name or external-fpga-config\n");
> +               fpga_image_info_free(dev, info);
>                 return -EINVAL;
>         }
>
> -       return fpga_region_program_fpga(region, firmware_name, nd->overlay);
> +       region->info = info;
> +       ret = fpga_region_program_fpga(region, nd->overlay);
> +       if (ret) {
> +               fpga_image_info_free(dev, info);
> +               region->info = NULL;
> +       }
> +
> +       return ret;
>  }
>
>  /**
> @@ -426,7 +439,7 @@ static void fpga_region_notify_post_remove(struct fpga_region *region,
>  {
>         fpga_bridges_disable(&region->bridge_list);
>         fpga_bridges_put(&region->bridge_list);
> -       devm_kfree(&region->dev, region->info);
> +       fpga_image_info_free(&region->dev, region->info);
>         region->info = NULL;
>  }
>
> diff --git a/include/linux/fpga/fpga-mgr.h b/include/linux/fpga/fpga-mgr.h
> index b4ac24c..1c53aa3 100644
> --- a/include/linux/fpga/fpga-mgr.h
> +++ b/include/linux/fpga/fpga-mgr.h
> @@ -1,7 +1,8 @@
>  /*
>   * FPGA Framework
>   *
> - *  Copyright (C) 2013-2015 Altera Corporation
> + *  Copyright (C) 2013-2016 Altera Corporation
> + *  Copyright (C) 2017 Intel Corporation
>   *
>   * This program is free software; you can redistribute it and/or modify it
>   * under the terms and conditions of the GNU General Public License,
> @@ -79,12 +80,20 @@ enum fpga_mgr_states {
>   * @disable_timeout_us: maximum time to disable traffic through bridge (uSec)
>   * @config_complete_timeout_us: maximum time for FPGA to switch to operating
>   *        status in the write_complete op.
> + * @firmware_name: name of FPGA image firmware file
> + * @sgt: scatter/gather table containing FPGA image
> + * @buf: contiguous buffer containing FPGA image
> + * @count: size of buf
>   */
>  struct fpga_image_info {
>         u32 flags;
>         u32 enable_timeout_us;
>         u32 disable_timeout_us;
>         u32 config_complete_timeout_us;
> +       char *firmware_name;
> +       struct sg_table *sgt;
> +       const char *buf;
> +       size_t count;
>  };
>
>  /**
> @@ -134,14 +143,11 @@ struct fpga_manager {
>
>  #define to_fpga_manager(d) container_of(d, struct fpga_manager, dev)
>
> -int fpga_mgr_buf_load(struct fpga_manager *mgr, struct fpga_image_info *info,
> -                     const char *buf, size_t count);
> -int fpga_mgr_buf_load_sg(struct fpga_manager *mgr, struct fpga_image_info *info,
> -                        struct sg_table *sgt);
> +struct fpga_image_info *fpga_image_info_alloc(struct device *dev);
>
> -int fpga_mgr_firmware_load(struct fpga_manager *mgr,
> -                          struct fpga_image_info *info,
> -                          const char *image_name);
> +void fpga_image_info_free(struct device *dev, struct fpga_image_info *info);
> +
> +int fpga_mgr_load(struct fpga_manager *mgr, struct fpga_image_info *info);
>
>  struct fpga_manager *of_fpga_mgr_get(struct device_node *node);
>
> --
> 2.7.4
>

Cheers,
Moritz

Re: [PATCH v3 03/16] fpga: mgr: API change to replace fpga load functions with single function

[Alan Tull]

On Mon, Jul 10, 2017 at 12:36 PM, Moritz Fischer
<moritz.fischer@ettus.com> wrote:

Hi Moritz,

Thanks for looking at this stuff.

>>
>> +struct fpga_image_info *fpga_image_info_alloc(struct device *dev)
>> +{
>> +       struct fpga_image_info *info;
>> +
>> +       info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
>> +       if (!info)
>> +               return ERR_PTR(-ENOMEM);
>
> Doesn't this make it more complex?

Yes!

> If in the end you'll anyway have to check
> if IS_ERR_OR_NULL()? As opposed to just checking if (!info) on the returned
> value.
>
> Just a thought.

Yes, I agree.

>> diff --git a/drivers/fpga/fpga-region.c b/drivers/fpga/fpga-region.c
>> index 655940f..c71c9cb 100644
>> --- a/drivers/fpga/fpga-region.c
>> +++ b/drivers/fpga/fpga-region.c
>> @@ -226,14 +226,11 @@ static int fpga_region_get_bridges(struct fpga_region *region,
>>  /**
>>   * fpga_region_program_fpga - program FPGA
>>   * @region: FPGA region
>> - * @firmware_name: name of FPGA image firmware file
>>   * @overlay: device node of the overlay
>> - * Program an FPGA using information in the device tree.
>> - * Function assumes that there is a firmware-name property.
>> + * Program an FPGA using information in the region's fpga image info.
>>   * Return 0 for success or negative error code.
>>   */
>>  static int fpga_region_program_fpga(struct fpga_region *region,
>> -                                   const char *firmware_name,
>>                                     struct device_node *overlay)
>>  {
>>         struct fpga_manager *mgr;
>> @@ -264,7 +261,7 @@ static int fpga_region_program_fpga(struct fpga_region *region,
>>                 goto err_put_br;
>>         }
>>
>> -       ret = fpga_mgr_firmware_load(mgr, region->info, firmware_name);
>> +       ret = fpga_mgr_load(mgr, region->info);
>>         if (ret) {
>>                 pr_err("failed to load fpga image\n");
>>                 goto err_put_br;
>> @@ -357,16 +354,15 @@ static int child_regions_with_firmware(struct device_node *overlay)
>>  static int fpga_region_notify_pre_apply(struct fpga_region *region,
>>                                         struct of_overlay_notify_data *nd)
>>  {
>> -       const char *firmware_name = NULL;
>> +       struct device *dev = &region->dev;
>>         struct fpga_image_info *info;
>> +       const char *firmware_name;
>>         int ret;
>>
>> -       info = devm_kzalloc(&region->dev, sizeof(*info), GFP_KERNEL);
>> +       info = fpga_image_info_alloc(dev);
>>         if (!info)
>>                 return -ENOMEM;
>
> Can't you return PTR_ERR(info) here (If you don't follow my suggestion above),
> or keep it the same here and follow my suggestion ;-)

I see I fell exactly into the trap :) I set for myself.

I'll fix the return value of fpga_image_info_alloc() as you suggested above.

Alan

Re: [PATCH v3 03/16] fpga: mgr: API change to replace fpga load functions with single function

[Alan Tull]

On Mon, Jul 10, 2017 at 12:36 PM, Moritz Fischer
<moritz.fischer@ettus.com> wrote:

>> +struct fpga_image_info *fpga_image_info_alloc(struct device *dev)
>> +{
>> +       struct fpga_image_info *info;
>> +
>> +       info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
>> +       if (!info)
>> +               return ERR_PTR(-ENOMEM);
>
> Doesn't this make it more complex? If in the end you'll anyway have to check
> if IS_ERR_OR_NULL()? As opposed to just checking if (!info) on the returned
> value.
>
> Just a thought.

Also I should save a pointer to the device in  fpga_image_info so that
fpga_image_info_free() could lose the dev param.  I'd add this here:

get_device(dev);
info->dev = dev;

>
>> +
>> +       return info;
>> +}
>> +EXPORT_SYMBOL_GPL(fpga_image_info_alloc);
>> +
>> +void fpga_image_info_free(struct device *dev,
>> +                         struct fpga_image_info *info)

I'd get rid of the dev parameter.

>> +{

struct device *dev;

>> +       if (!info)
>> +               return;

dev = info->dev;

>> +
>> +       if (info->firmware_name)
>> +               devm_kfree(dev, info->firmware_name);
>> +
>> +       devm_kfree(dev, info);

put_device(dev);

>> +}
>> +EXPORT_SYMBOL_GPL(fpga_image_info_free);

And fix all uses of this function to be fpga_image_info_free(info);

Alan Tull

Re: [PATCH v3 01/16] doc: fpga: update documents for the FPGA API

[Moritz Fischer]

Hi Alan,

I think that should go together with [3/16] in one commit,
to make API change go together with actual change?

On Thu, Jul 6, 2017 at 11:47 AM, Alan Tull <atull@kernel.org> wrote:
> The FPGA manager has been simplified to have a single
> fpga_mgr_load function which replaces the three
> fpga_mgr_*load* functions.
>
> The parameters presenting the FPGA image have been
> added to struct fpga_image_info.
>
> Additional functions have been added to alloc/free
> fpga_image_info.
>
> Getting a FPGA manager has been separated from
> locking it.  So an unlocked reference can be saved and
> only locked when we're about to program.
>
> A document for fpga-region has been added as well.
>
> Signed-off-by: Alan Tull <atull@kernel.org>
> ---
>  Documentation/fpga/fpga-mgr.txt    | 133 +++++++++++++++++++------------------
>  Documentation/fpga/fpga-region.txt |  95 ++++++++++++++++++++++++++
>  Documentation/fpga/overview.txt    |  23 +++++++
>  3 files changed, 188 insertions(+), 63 deletions(-)
>  create mode 100644 Documentation/fpga/fpga-region.txt
>  create mode 100644 Documentation/fpga/overview.txt
>
> diff --git a/Documentation/fpga/fpga-mgr.txt b/Documentation/fpga/fpga-mgr.txt
> index 78f197f..0fc41eb 100644
> --- a/Documentation/fpga/fpga-mgr.txt
> +++ b/Documentation/fpga/fpga-mgr.txt
> @@ -11,61 +11,66 @@ hidden away in a low level driver which registers a set of ops with the core.
>  The FPGA image data itself is very manufacturer specific, but for our purposes
>  it's just binary data.  The FPGA manager core won't parse it.
>
> +The FPGA image to be programmed can be in a scatter gather list, a single
> +contiguous buffer, or a firmware file.  Because allocating contiguous kernel
> +memory for the buffer should be avoided, users are encouraged to use a scatter
> +gather list instead if possible.
> +
> +The particulars for programming the image are presented in a structure (struct
> +fpga_image_info).  This struct contains parameters such as pointers to the
> +FPGA image as well as image-specific particulars such as whether the image was
> +built for full or partial reconfiguration.
>
>  API Functions:
>  ==============
>
> -To program the FPGA from a file or from a buffer:
> --------------------------------------------------
> -
> -       int fpga_mgr_buf_load(struct fpga_manager *mgr,
> -                             struct fpga_image_info *info,
> -                             const char *buf, size_t count);
> -
> -Load the FPGA from an image which exists as a contiguous buffer in
> -memory. Allocating contiguous kernel memory for the buffer should be avoided,
> -users are encouraged to use the _sg interface instead of this.
> -
> -        int fpga_mgr_buf_load_sg(struct fpga_manager *mgr,
> -                                struct fpga_image_info *info,
> -                                struct sg_table *sgt);
> +To program the FPGA:
> +--------------------
>
> -Load the FPGA from an image from non-contiguous in memory. Callers can
> -construct a sg_table using alloc_page backed memory.
> +       int fpga_mgr_load(struct fpga_manager *mgr,
> +                         struct fpga_image_info *info);
>
> -       int fpga_mgr_firmware_load(struct fpga_manager *mgr,
> -                                  struct fpga_image_info *info,
> -                                  const char *image_name);
> -
> -Load the FPGA from an image which exists as a file.  The image file must be on
> -the firmware search path (see the firmware class documentation).  If successful,
> +Load the FPGA from an image which is indicated in the info.  If successful,
>  the FPGA ends up in operating mode.  Return 0 on success or a negative error
>  code.
>
> -A FPGA design contained in a FPGA image file will likely have particulars that
> -affect how the image is programmed to the FPGA.  These are contained in struct
> -fpga_image_info.  Currently the only such particular is a single flag bit
> -indicating whether the image is for full or partial reconfiguration.
> +To allocate or free a struct fpga_image_info:
> +---------------------------------------------
> +
> +       struct fpga_image_info *fpga_image_info_alloc(struct device *dev);
> +
> +       void fpga_image_info_free(struct device *dev,
> +                                 struct fpga_image_info *info);
>
>  To get/put a reference to a FPGA manager:
>  -----------------------------------------
>
>         struct fpga_manager *of_fpga_mgr_get(struct device_node *node);
>         struct fpga_manager *fpga_mgr_get(struct device *dev);
> +       void fpga_mgr_put(struct fpga_manager *mgr);
>
> -Given a DT node or device, get an exclusive reference to a FPGA manager.
> +Given a DT node or device, get a reference to a FPGA manager.  This pointer
> +can be saved until you are ready to program the FPGA.  fpga_mgr_put
> +releases the reference.
>
> -       void fpga_mgr_put(struct fpga_manager *mgr);
>
> -Release the reference.
> +To get exclusive control of a FPGA manager:
> +-------------------------------------------
> +
> +       int fpga_mgr_lock(struct fpga_magager *mgr);
> +       void fpga_mgr_unlock(struct fpga_magager *mgr);
> +
> +The user should call fpga_mgr_lock and verify that it returns 0 before
> +attempting to program the FPGA.  Likeqise, the user should call
> +fpga_mgr_unlock when done programming the FPGA.
>
>
>  To register or unregister the low level FPGA-specific driver:
>  -------------------------------------------------------------
>
>         int fpga_mgr_register(struct device *dev, const char *name,
> -                             const struct fpga_manager_ops *mops,
> -                             void *priv);
> +                             const struct fpga_manager_ops *mops,
> +                             void *priv);
>
>         void fpga_mgr_unregister(struct device *dev);
>
> @@ -78,59 +83,61 @@ How to write an image buffer to a supported FPGA
>  /* Include to get the API */
>  #include <linux/fpga/fpga-mgr.h>
>
> -/* device node that specifies the FPGA manager to use */
> -struct device_node *mgr_node = ...
> +struct fpga_manager *mgr;
> +struct fpga_image_info *info;
> +int ret;
>
> -/* FPGA image is in this buffer.  count is size of the buffer. */
> -char *buf = ...
> -int count = ...
> +/*
> + * Get a reference to FPGA manager.  This example uses the  device node of the
> + * manager.  You could use fpga_mgr_get() instead if you have the device instead
> + * of the device node.
> + */
> +mgr = of_fpga_mgr_get(mgr_node);
>
>  /* struct with information about the FPGA image to program. */
> -struct fpga_image_info info;
> +info = fpga_image_info_alloc(dev);
>
>  /* flags indicates whether to do full or partial reconfiguration */
> -info.flags = 0;
> +info->flags = FPGA_MGR_PARTIAL_RECONFIG;
>
> -int ret;
> +/*
> + * At this point, indicate where the image is. This is pseudo-code; you're
> + * probably going to use one of these three.
> + */
> +if (using scatter gather) {
>
> -/* Get exclusive control of FPGA manager */
> -struct fpga_manager *mgr = of_fpga_mgr_get(mgr_node);
> +       info->sgt = [your scatter gather table]
>
> -/* Load the buffer to the FPGA */
> -ret = fpga_mgr_buf_load(mgr, &info, buf, count);
> -
> -/* Release the FPGA manager */
> -fpga_mgr_put(mgr);
> +} else if (using a buffer) {
>
> +       info->buf = [your image buffer]
> +       info->count = [image buffer size]
>
> -How to write an image file to a supported FPGA
> -==============================================
> -/* Include to get the API */
> -#include <linux/fpga/fpga-mgr.h>
> -
> -/* device node that specifies the FPGA manager to use */
> -struct device_node *mgr_node = ...
> +} else if (using a firmware file) {
>
> -/* FPGA image is in this file which is in the firmware search path */
> -const char *path = "fpga-image-9.rbf"
> +       info->firmware_name = devm_kstrdup(dev, firmware_name, GFP_KERNEL);
>
> -/* struct with information about the FPGA image to program. */
> -struct fpga_image_info info;
> +} else {
>
> -/* flags indicates whether to do full or partial reconfiguration */
> -info.flags = 0;
> +       not implemented!
>
> -int ret;
> +}
>
>  /* Get exclusive control of FPGA manager */
> -struct fpga_manager *mgr = of_fpga_mgr_get(mgr_node);
> +ret = fpga_mgr_lock(mgr);
>
> -/* Get the firmware image (path) and load it to the FPGA */
> -ret = fpga_mgr_firmware_load(mgr, &info, path);
> +/* Load the buffer to the FPGA */
> +ret = fpga_mgr_buf_load(mgr, &info, buf, count);
>
>  /* Release the FPGA manager */
> +fpga_mgr_unlock(mgr);
>  fpga_mgr_put(mgr);
>
> +/* Free your image storage in some appropriate way */
> +...
> +
> +/* Deallocate the image info if you're done with it */
> +fpga_image_info_free(dev, info);
>
>  How to support a new FPGA device
>  ================================
> diff --git a/Documentation/fpga/fpga-region.txt b/Documentation/fpga/fpga-region.txt
> new file mode 100644
> index 0000000..139a02b
> --- /dev/null
> +++ b/Documentation/fpga/fpga-region.txt
> @@ -0,0 +1,95 @@
> +FPGA Regions
> +
> +Alan Tull 2017
> +
> +CONTENTS
> + - Introduction
> + - The FPGA region API
> + - Usage example
> +
> +Introduction
> +============
> +
> +This document is meant to be an brief overview of the FPGA region API usage.  A
> +more conceptual look at regions can be found in [1].
> +
> +For the purposes of this API document, let's just say that a region associates
> +an FPGA Manager and a bridge (or bridges) with a reprogrammable region of an
> +FPGA or the whole FPGA.  The API provides a way to register a region and to
> +program a region.
> +
> +Currently the only layer above fpga-region.c in the kernel is the Device Tree
> +support (of-fpga-region.c) described in [1].  The DT support layer uses regions
> +to program the FPGA and then DT to handle enumeration.  The common region code
> +is intended to be used by other schemes that have other ways of accomplishing
> +enumeration after programming.
> +
> +An fpga-region can be set up to know the following things:
> +* which FPGA manager to use to do the programming
> +* which bridges to disable before programming and enable afterwards.
> +
> +Additional info needed to program the FPGA image is passed in the struct
> +fpga_image_info [2] including:
> +* pointers to the image as either a scatter-gather buffer, a contiguous
> +  buffer, or the name of firmware file
> +* flags indicating specifics such as whether the image if for partial
> +  reconfiguration.
> +
> +===================
> +The FPGA region API
> +===================
> +
> +To register or unregister a region:
> +-----------------------------------
> +
> +       int fpga_region_register(struct device *dev,
> +                                struct fpga_region *region);
> +       int fpga_region_unregister(struct fpga_region *region);
> +
> +An example of usage can be seen in the probe function of [3]
> +
> +To program an FPGA:
> +-------------------
> +       int fpga_region_program_fpga(struct fpga_region *region);
> +
> +This function operates on info passed in the fpga_image_info
> +(region->info).
> +
> +This function will attempt to:
> + * lock the region's mutex
> + * lock the region's FPGA manager
> + * build a list of FPGA bridges if a method has been specified to do so
> + * disable the bridges
> + * program the FPGA
> + * re-enable the bridges
> + * release the locks
> +
> +=============
> +Usage example
> +=============
> +
> +First, allocate the info struct:
> +
> +       info = fpga_image_info_alloc(dev);
> +       if (!info)
> +               return -ENOMEM;
> +
> +Set flags as needed, i.e.
> +
> +       info->flags |= FPGA_MGR_PARTIAL_RECONFIG;
> +
> +Point to your FPGA image, such as:
> +
> +       info->sgt = &sgt;
> +
> +Add info to region and do the programming:
> +
> +       region->info = info;
> +       ret = fpga_region_program_fpga(region);
> +
> +Then enumerate whatever hardware has appeared in the FPGA.
> +
> +--
> +[1] ../devicetree/bindings/fpga/fpga-region.txt
> +[2] ./fpga-mgr.txt
> +[3] ../../drivers/fpga/of-fpga-region.c
> diff --git a/Documentation/fpga/overview.txt b/Documentation/fpga/overview.txt
> new file mode 100644
> index 0000000..149ac8a
> --- /dev/null
> +++ b/Documentation/fpga/overview.txt
> @@ -0,0 +1,23 @@
> +Linux kernel FPGA support
> +
> +Alan Tull 2017
> +
> +The main point of this project has been to separate the out the upper layers
> +that know when to reprogram a FPGA from the lower layers that know how to
> +reprogram a specific FPGA device.  The intention is to make this manufacturor
> +agnostic, understanding that of course the FPGA images are very device specific
> +themselves.
> +
> +At this point it time, the framework in the kernel includes:
> +* low level FPGA manager drivers that know how to program a specific device
> +* the fpga-mgr framework they are registered with
> +* low level FPGA bridge drivers for hard/soft bridges which are intended to
> +  be disable during FPGA programming
> +* the fpga-bridge framework they are registered with
> +* the fpga-region framework which associates and controls managers and bridges
> +  as reconfigurable regions
> +* the of-fpga-region support for reprogramming FPGAs when device tree overlays
> +  are applied.
> +
> +I would encourage you the user to add code that creates fpga regions rather
> +that trying to control managers and bridges separately.
> --
> 2.7.4
>

Cheers,

Moritz

Re: [PATCH v3 01/16] doc: fpga: update documents for the FPGA API

[Alan Tull]

On Thu, Aug 17, 2017 at 2:42 PM, Moritz Fischer
<moritz.fischer@ettus.com> wrote:
> Hi Alan,
>
> I think that should go together with [3/16] in one commit,
> to make API change go together with actual change?

Yes, the patches will be going in together anyway (not through
separate maintainers), so I could do that.  I hope to post the next
version in a couple weeks.

Alan

>
> On Thu, Jul 6, 2017 at 11:47 AM, Alan Tull <atull@kernel.org> wrote:
>> The FPGA manager has been simplified to have a single
>> fpga_mgr_load function which replaces the three
>> fpga_mgr_*load* functions.
>>
>> The parameters presenting the FPGA image have been
>> added to struct fpga_image_info.
>>
>> Additional functions have been added to alloc/free
>> fpga_image_info.
>>
>> Getting a FPGA manager has been separated from
>> locking it.  So an unlocked reference can be saved and
>> only locked when we're about to program.
>>
>> A document for fpga-region has been added as well.
>>
>> Signed-off-by: Alan Tull <atull@kernel.org>
>> ---
>>  Documentation/fpga/fpga-mgr.txt    | 133 +++++++++++++++++++------------------
>>  Documentation/fpga/fpga-region.txt |  95 ++++++++++++++++++++++++++
>>  Documentation/fpga/overview.txt    |  23 +++++++
>>  3 files changed, 188 insertions(+), 63 deletions(-)
>>  create mode 100644 Documentation/fpga/fpga-region.txt
>>  create mode 100644 Documentation/fpga/overview.txt
>>
>> diff --git a/Documentation/fpga/fpga-mgr.txt b/Documentation/fpga/fpga-mgr.txt
>> index 78f197f..0fc41eb 100644
>> --- a/Documentation/fpga/fpga-mgr.txt
>> +++ b/Documentation/fpga/fpga-mgr.txt
>> @@ -11,61 +11,66 @@ hidden away in a low level driver which registers a set of ops with the core.
>>  The FPGA image data itself is very manufacturer specific, but for our purposes
>>  it's just binary data.  The FPGA manager core won't parse it.
>>
>> +The FPGA image to be programmed can be in a scatter gather list, a single
>> +contiguous buffer, or a firmware file.  Because allocating contiguous kernel
>> +memory for the buffer should be avoided, users are encouraged to use a scatter
>> +gather list instead if possible.
>> +
>> +The particulars for programming the image are presented in a structure (struct
>> +fpga_image_info).  This struct contains parameters such as pointers to the
>> +FPGA image as well as image-specific particulars such as whether the image was
>> +built for full or partial reconfiguration.
>>
>>  API Functions:
>>  ==============
>>
>> -To program the FPGA from a file or from a buffer:
>> --------------------------------------------------
>> -
>> -       int fpga_mgr_buf_load(struct fpga_manager *mgr,
>> -                             struct fpga_image_info *info,
>> -                             const char *buf, size_t count);
>> -
>> -Load the FPGA from an image which exists as a contiguous buffer in
>> -memory. Allocating contiguous kernel memory for the buffer should be avoided,
>> -users are encouraged to use the _sg interface instead of this.
>> -
>> -        int fpga_mgr_buf_load_sg(struct fpga_manager *mgr,
>> -                                struct fpga_image_info *info,
>> -                                struct sg_table *sgt);
>> +To program the FPGA:
>> +--------------------
>>
>> -Load the FPGA from an image from non-contiguous in memory. Callers can
>> -construct a sg_table using alloc_page backed memory.
>> +       int fpga_mgr_load(struct fpga_manager *mgr,
>> +                         struct fpga_image_info *info);
>>
>> -       int fpga_mgr_firmware_load(struct fpga_manager *mgr,
>> -                                  struct fpga_image_info *info,
>> -                                  const char *image_name);
>> -
>> -Load the FPGA from an image which exists as a file.  The image file must be on
>> -the firmware search path (see the firmware class documentation).  If successful,
>> +Load the FPGA from an image which is indicated in the info.  If successful,
>>  the FPGA ends up in operating mode.  Return 0 on success or a negative error
>>  code.
>>
>> -A FPGA design contained in a FPGA image file will likely have particulars that
>> -affect how the image is programmed to the FPGA.  These are contained in struct
>> -fpga_image_info.  Currently the only such particular is a single flag bit
>> -indicating whether the image is for full or partial reconfiguration.
>> +To allocate or free a struct fpga_image_info:
>> +---------------------------------------------
>> +
>> +       struct fpga_image_info *fpga_image_info_alloc(struct device *dev);
>> +
>> +       void fpga_image_info_free(struct device *dev,
>> +                                 struct fpga_image_info *info);
>>
>>  To get/put a reference to a FPGA manager:
>>  -----------------------------------------
>>
>>         struct fpga_manager *of_fpga_mgr_get(struct device_node *node);
>>         struct fpga_manager *fpga_mgr_get(struct device *dev);
>> +       void fpga_mgr_put(struct fpga_manager *mgr);
>>
>> -Given a DT node or device, get an exclusive reference to a FPGA manager.
>> +Given a DT node or device, get a reference to a FPGA manager.  This pointer
>> +can be saved until you are ready to program the FPGA.  fpga_mgr_put
>> +releases the reference.
>>
>> -       void fpga_mgr_put(struct fpga_manager *mgr);
>>
>> -Release the reference.
>> +To get exclusive control of a FPGA manager:
>> +-------------------------------------------
>> +
>> +       int fpga_mgr_lock(struct fpga_magager *mgr);
>> +       void fpga_mgr_unlock(struct fpga_magager *mgr);
>> +
>> +The user should call fpga_mgr_lock and verify that it returns 0 before
>> +attempting to program the FPGA.  Likeqise, the user should call
>> +fpga_mgr_unlock when done programming the FPGA.
>>
>>
>>  To register or unregister the low level FPGA-specific driver:
>>  -------------------------------------------------------------
>>
>>         int fpga_mgr_register(struct device *dev, const char *name,
>> -                             const struct fpga_manager_ops *mops,
>> -                             void *priv);
>> +                             const struct fpga_manager_ops *mops,
>> +                             void *priv);
>>
>>         void fpga_mgr_unregister(struct device *dev);
>>
>> @@ -78,59 +83,61 @@ How to write an image buffer to a supported FPGA
>>  /* Include to get the API */
>>  #include <linux/fpga/fpga-mgr.h>
>>
>> -/* device node that specifies the FPGA manager to use */
>> -struct device_node *mgr_node = ...
>> +struct fpga_manager *mgr;
>> +struct fpga_image_info *info;
>> +int ret;
>>
>> -/* FPGA image is in this buffer.  count is size of the buffer. */
>> -char *buf = ...
>> -int count = ...
>> +/*
>> + * Get a reference to FPGA manager.  This example uses the  device node of the
>> + * manager.  You could use fpga_mgr_get() instead if you have the device instead
>> + * of the device node.
>> + */
>> +mgr = of_fpga_mgr_get(mgr_node);
>>
>>  /* struct with information about the FPGA image to program. */
>> -struct fpga_image_info info;
>> +info = fpga_image_info_alloc(dev);
>>
>>  /* flags indicates whether to do full or partial reconfiguration */
>> -info.flags = 0;
>> +info->flags = FPGA_MGR_PARTIAL_RECONFIG;
>>
>> -int ret;
>> +/*
>> + * At this point, indicate where the image is. This is pseudo-code; you're
>> + * probably going to use one of these three.
>> + */
>> +if (using scatter gather) {
>>
>> -/* Get exclusive control of FPGA manager */
>> -struct fpga_manager *mgr = of_fpga_mgr_get(mgr_node);
>> +       info->sgt = [your scatter gather table]
>>
>> -/* Load the buffer to the FPGA */
>> -ret = fpga_mgr_buf_load(mgr, &info, buf, count);
>> -
>> -/* Release the FPGA manager */
>> -fpga_mgr_put(mgr);
>> +} else if (using a buffer) {
>>
>> +       info->buf = [your image buffer]
>> +       info->count = [image buffer size]
>>
>> -How to write an image file to a supported FPGA
>> -==============================================
>> -/* Include to get the API */
>> -#include <linux/fpga/fpga-mgr.h>
>> -
>> -/* device node that specifies the FPGA manager to use */
>> -struct device_node *mgr_node = ...
>> +} else if (using a firmware file) {
>>
>> -/* FPGA image is in this file which is in the firmware search path */
>> -const char *path = "fpga-image-9.rbf"
>> +       info->firmware_name = devm_kstrdup(dev, firmware_name, GFP_KERNEL);
>>
>> -/* struct with information about the FPGA image to program. */
>> -struct fpga_image_info info;
>> +} else {
>>
>> -/* flags indicates whether to do full or partial reconfiguration */
>> -info.flags = 0;
>> +       not implemented!
>>
>> -int ret;
>> +}
>>
>>  /* Get exclusive control of FPGA manager */
>> -struct fpga_manager *mgr = of_fpga_mgr_get(mgr_node);
>> +ret = fpga_mgr_lock(mgr);
>>
>> -/* Get the firmware image (path) and load it to the FPGA */
>> -ret = fpga_mgr_firmware_load(mgr, &info, path);
>> +/* Load the buffer to the FPGA */
>> +ret = fpga_mgr_buf_load(mgr, &info, buf, count);
>>
>>  /* Release the FPGA manager */
>> +fpga_mgr_unlock(mgr);
>>  fpga_mgr_put(mgr);
>>
>> +/* Free your image storage in some appropriate way */
>> +...
>> +
>> +/* Deallocate the image info if you're done with it */
>> +fpga_image_info_free(dev, info);
>>
>>  How to support a new FPGA device
>>  ================================
>> diff --git a/Documentation/fpga/fpga-region.txt b/Documentation/fpga/fpga-region.txt
>> new file mode 100644
>> index 0000000..139a02b
>> --- /dev/null
>> +++ b/Documentation/fpga/fpga-region.txt
>> @@ -0,0 +1,95 @@
>> +FPGA Regions
>> +
>> +Alan Tull 2017
>> +
>> +CONTENTS
>> + - Introduction
>> + - The FPGA region API
>> + - Usage example
>> +
>> +Introduction
>> +============
>> +
>> +This document is meant to be an brief overview of the FPGA region API usage.  A
>> +more conceptual look at regions can be found in [1].
>> +
>> +For the purposes of this API document, let's just say that a region associates
>> +an FPGA Manager and a bridge (or bridges) with a reprogrammable region of an
>> +FPGA or the whole FPGA.  The API provides a way to register a region and to
>> +program a region.
>> +
>> +Currently the only layer above fpga-region.c in the kernel is the Device Tree
>> +support (of-fpga-region.c) described in [1].  The DT support layer uses regions
>> +to program the FPGA and then DT to handle enumeration.  The common region code
>> +is intended to be used by other schemes that have other ways of accomplishing
>> +enumeration after programming.
>> +
>> +An fpga-region can be set up to know the following things:
>> +* which FPGA manager to use to do the programming
>> +* which bridges to disable before programming and enable afterwards.
>> +
>> +Additional info needed to program the FPGA image is passed in the struct
>> +fpga_image_info [2] including:
>> +* pointers to the image as either a scatter-gather buffer, a contiguous
>> +  buffer, or the name of firmware file
>> +* flags indicating specifics such as whether the image if for partial
>> +  reconfiguration.
>> +
>> +===================
>> +The FPGA region API
>> +===================
>> +
>> +To register or unregister a region:
>> +-----------------------------------
>> +
>> +       int fpga_region_register(struct device *dev,
>> +                                struct fpga_region *region);
>> +       int fpga_region_unregister(struct fpga_region *region);
>> +
>> +An example of usage can be seen in the probe function of [3]
>> +
>> +To program an FPGA:
>> +-------------------
>> +       int fpga_region_program_fpga(struct fpga_region *region);
>> +
>> +This function operates on info passed in the fpga_image_info
>> +(region->info).
>> +
>> +This function will attempt to:
>> + * lock the region's mutex
>> + * lock the region's FPGA manager
>> + * build a list of FPGA bridges if a method has been specified to do so
>> + * disable the bridges
>> + * program the FPGA
>> + * re-enable the bridges
>> + * release the locks
>> +
>> +=============
>> +Usage example
>> +=============
>> +
>> +First, allocate the info struct:
>> +
>> +       info = fpga_image_info_alloc(dev);
>> +       if (!info)
>> +               return -ENOMEM;
>> +
>> +Set flags as needed, i.e.
>> +
>> +       info->flags |= FPGA_MGR_PARTIAL_RECONFIG;
>> +
>> +Point to your FPGA image, such as:
>> +
>> +       info->sgt = &sgt;
>> +
>> +Add info to region and do the programming:
>> +
>> +       region->info = info;
>> +       ret = fpga_region_program_fpga(region);
>> +
>> +Then enumerate whatever hardware has appeared in the FPGA.
>> +
>> +--
>> +[1] ../devicetree/bindings/fpga/fpga-region.txt
>> +[2] ./fpga-mgr.txt
>> +[3] ../../drivers/fpga/of-fpga-region.c
>> diff --git a/Documentation/fpga/overview.txt b/Documentation/fpga/overview.txt
>> new file mode 100644
>> index 0000000..149ac8a
>> --- /dev/null
>> +++ b/Documentation/fpga/overview.txt
>> @@ -0,0 +1,23 @@
>> +Linux kernel FPGA support
>> +
>> +Alan Tull 2017
>> +
>> +The main point of this project has been to separate the out the upper layers
>> +that know when to reprogram a FPGA from the lower layers that know how to
>> +reprogram a specific FPGA device.  The intention is to make this manufacturor
>> +agnostic, understanding that of course the FPGA images are very device specific
>> +themselves.
>> +
>> +At this point it time, the framework in the kernel includes:
>> +* low level FPGA manager drivers that know how to program a specific device
>> +* the fpga-mgr framework they are registered with
>> +* low level FPGA bridge drivers for hard/soft bridges which are intended to
>> +  be disable during FPGA programming
>> +* the fpga-bridge framework they are registered with
>> +* the fpga-region framework which associates and controls managers and bridges
>> +  as reconfigurable regions
>> +* the of-fpga-region support for reprogramming FPGAs when device tree overlays
>> +  are applied.
>> +
>> +I would encourage you the user to add code that creates fpga regions rather
>> +that trying to control managers and bridges separately.
>> --
>> 2.7.4
>>
>
> Cheers,
>
> Moritz