This adds the possibility to configure the place for the environment
from the devicetree and to partition devices from the devicetree.
Configuration has the general form of devices with a regular compatible
property. This allows to later add additional drivers or drivers with
different behaviour (for example to add support for redundant environment).
The configuration is all in the /chosen/barebox/ hierarchy of the
devicetree. This separates the configuration from the hardware
description. Also it makes it possible to store the configuration
in a completely separate devicetree (or devicetree overlay). For
the same reason all configuration is done using nodepathes rather
than phandles.
Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
---
Documentation/devicetree/bindings/barebox.txt | 10 ++
.../bindings/barebox/barebox,environment.txt | 24 +++
.../bindings/barebox/barebox,partition.txt | 42 +++++
drivers/of/Kconfig | 9 +
drivers/of/Makefile | 1 +
drivers/of/barebox.c | 191 +++++++++++++++++++++
drivers/of/of_path.c | 155 +++++++++++++++++
fs/devfs-core.c | 2 +
include/driver.h | 5 +
include/of.h | 11 ++
10 files changed, 450 insertions(+)
create mode 100644 Documentation/devicetree/bindings/barebox.txt
create mode 100644 Documentation/devicetree/bindings/barebox/barebox,environment.txt
create mode 100644 Documentation/devicetree/bindings/barebox/barebox,partition.txt
create mode 100644 drivers/of/barebox.c
create mode 100644 drivers/of/of_path.c
diff --git a/Documentation/devicetree/bindings/barebox.txt b/Documentation/devicetree/bindings/barebox.txt
new file mode 100644
index 0000000..906c4bc
--- /dev/null
+++ b/Documentation/devicetree/bindings/barebox.txt
@@ -0,0 +1,10 @@
+barebox specific devicetree bindings
+====================================
+
+barebox uses some barebox specific devicetree bindings. All of these
+are under the /chosen/barebox/ hierarchy in the devicetree.
+
+The bindings have the form of a device with regular 'compatible' properties.
+drivers matching these devices do not handle physical devices but instead
+influence / configure certain behaviours of barebox like the place where to
+find the persistent environment or the partitioning of devices.
diff --git a/Documentation/devicetree/bindings/barebox/barebox,environment.txt b/Documentation/devicetree/bindings/barebox/barebox,environment.txt
new file mode 100644
index 0000000..48fd376
--- /dev/null
+++ b/Documentation/devicetree/bindings/barebox/barebox,environment.txt
@@ -0,0 +1,24 @@
+barebox environment
+
+This driver provides an environment for barebox from the devicetree.
+
+Required properties:
+- compatible: should be "barebox,environment"
+- device-path: path to the environment
+
+The device-path is a multistring property. The first string should be a
+nodepath to the node containing the physical device of the environment.
+The subsequent strings are of the form <type>:<options> to further describe
+the path to the environment. Supported values for <type>:
+
+partname:<partname> This describes a partition on a device. <partname> can
+ be the label for mtd partitions, the number for DOS
+ partitions (beginning with 0) or the name for GPT
+ partitions
+
+Example:
+
+environment@0 {
+ compatible = "barebox,environment";
+ device-path = &flash, "partname:barebox-environment";
+};
diff --git a/Documentation/devicetree/bindings/barebox/barebox,partition.txt b/Documentation/devicetree/bindings/barebox/barebox,partition.txt
new file mode 100644
index 0000000..f38e76d
--- /dev/null
+++ b/Documentation/devicetree/bindings/barebox/barebox,partition.txt
@@ -0,0 +1,42 @@
+partition provider
+
+Driver to provide a partitioning for mtd devices. barebox provides a
+separate driver for this instead of positioning the partitions under
+the devicenode which actually provides the partitions. The reason for
+this is that the devicetree contains the hardware description whereas
+the partitioning of a device is not hardware specific. Having a separate
+driver makes it possible to separate the hardware devicetree from the
+configuration.
+
+Required properties:
+
+- compatible: should be "barebox,partition"
+- device-path: should contain a nodepath to the physical device for which
+ this device provides a partitioning
+- #address-cells, #size-cells: number of cells for size/addresses in the
+ partitions
+
+Partition properties:
+
+- reg: The partition's offset and size
+- label: The label/name for this partition
+- read-only: if present, the partition is read-only
+
+Example:
+
+nor-partitions {
+ compatible = "barebox,partition";
+ device-path = &flash;
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ partition@0 {
+ label = "barebox";
+ reg = <0x0 0x80000>;
+ };
+
+ partition@1 {
+ label = "barebox-environment";
+ reg = <0x80000 0x80000>;
+ };
+};
diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index 03ae599..ab5eac8 100644
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -18,3 +18,12 @@ config OFDEVICE
config OF_NET
depends on NET
def_bool y
+
+config OF_BAREBOX_DRIVERS
+ depends on OFDEVICE
+ bool "Enable barebox specific devicetree configuration drivers"
+ help
+ barebox supports being configured from devicetree. This enables
+ support for this feature. This currently allows to configure the
+ environment path from devicetree and to partition devices. See
+ Documentation/devicetree/bindings/barebox/ for more information.
diff --git a/drivers/of/Makefile b/drivers/of/Makefile
index e7d0733..97fea9d 100644
--- a/drivers/of/Makefile
+++ b/drivers/of/Makefile
@@ -3,3 +3,4 @@ obj-$(CONFIG_OFTREE_MEM_GENERIC) += mem_generic.o
obj-$(CONFIG_GPIOLIB) += of_gpio.o
obj-y += partition.o
obj-y += of_net.o
+obj-$(CONFIG_OF_BAREBOX_DRIVERS) += barebox.o of_path.o
diff --git a/drivers/of/barebox.c b/drivers/of/barebox.c
new file mode 100644
index 0000000..4d178a8
--- /dev/null
+++ b/drivers/of/barebox.c
@@ -0,0 +1,191 @@
+/*
+ * barebox.c
+ *
+ * Copyright (c) 2013 Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>, Pengutronix
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that 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.
+ *
+ */
+
+#include <common.h>
+#include <init.h>
+#include <io.h>
+#include <of.h>
+#include <malloc.h>
+#include <partition.h>
+#include <envfs.h>
+
+struct of_partition {
+ struct list_head list;
+ char *nodepath;
+ struct device_d *dev;
+};
+
+static LIST_HEAD(of_partition_list);
+
+static struct device_node *cdev_find_node(struct cdev *cdev)
+{
+ struct device_d *dev = cdev->dev;
+
+ while (dev) {
+ if (dev->device_node)
+ return dev->device_node;
+
+ dev = dev->parent;
+ }
+
+ return NULL;
+}
+
+void of_cdev_register(struct cdev *cdev)
+{
+ struct device_node *np, *child;
+ struct of_partition *op;
+
+ if (cdev->flags & DEVFS_IS_PARTITION)
+ return;
+
+ if (cdev->partname)
+ return;
+
+ np = cdev_find_node(cdev);
+ if (!np)
+ return;
+
+ list_for_each_entry(op, &of_partition_list, list)
+ if (!strcmp(np->full_name, op->nodepath))
+ goto found;
+
+ return;
+
+found:
+ for_each_child_of_node(op->dev->device_node, child) {
+ dev_dbg(op->dev, "adding partition %s to %s\n", child->name,
+ cdev->name);
+ of_parse_partition(cdev, child);
+ }
+
+ list_del(&op->list);
+ free(op);
+}
+
+struct device_d *of_find_device_by_node_path(const char *path)
+{
+ struct device_d *dev;
+
+ for_each_device(dev) {
+ if (!dev->device_node)
+ continue;
+ if (!strcmp(path, dev->device_node->full_name))
+ return dev;
+ }
+
+ return NULL;
+}
+
+static int partition_probe(struct device_d *dev)
+{
+ const char *path;
+ struct device_node *node = dev->device_node;
+ int len;
+ struct of_partition *op;
+ struct cdev *cdev;
+
+ path = of_get_property(node, "device-path", &len);
+ if (!path) {
+ dev_err(dev, "cannot find 'device-path' property\n");
+ return -EINVAL;
+ }
+
+ node = of_find_node_by_path(path);
+ if (!node) {
+ dev_err(dev, "cannot find node with path '%s'\n", path);
+ return -ENODEV;
+ }
+
+ op = xzalloc(sizeof(*op));
+ op->nodepath = xstrdup(path);
+ op->dev = dev;
+
+ list_add_tail(&op->list, &of_partition_list);
+
+ cdev_for_each(cdev)
+ of_cdev_register(cdev);
+
+ return 0;
+}
+
+static struct of_device_id partition_dt_ids[] = {
+ {
+ .compatible = "barebox,partition",
+ }, {
+ /* sentinel */
+ }
+};
+
+static struct driver_d partition_driver = {
+ .name = "barebox-partition",
+ .probe = partition_probe,
+ .of_compatible = partition_dt_ids,
+};
+
+static int environment_probe(struct device_d *dev)
+{
+ char *path;
+ int ret;
+
+ ret = of_find_path(dev->device_node, "device-path", &path);
+ if (ret)
+ return ret;
+
+ dev_info(dev, "setting default environment path to %s\n", path);
+
+ default_environment_path = path;
+
+ return 0;
+}
+
+static struct of_device_id environment_dt_ids[] = {
+ {
+ .compatible = "barebox,environment",
+ }, {
+ /* sentinel */
+ }
+};
+
+static struct driver_d environment_driver = {
+ .name = "barebox-environment",
+ .probe = environment_probe,
+ .of_compatible = environment_dt_ids,
+};
+
+static int barebox_of_driver_init(void)
+{
+ struct device_node *node;
+
+ node = of_get_root_node();
+ if (!node)
+ return 0;
+
+ node = of_find_node_by_path("/chosen/barebox");
+ if (!node)
+ return 0;
+
+ of_platform_populate(node, of_default_bus_match_table, NULL);
+
+ platform_driver_register(&partition_driver);
+ platform_driver_register(&environment_driver);
+
+ return 0;
+}
+late_initcall(barebox_of_driver_init);
diff --git a/drivers/of/of_path.c b/drivers/of/of_path.c
new file mode 100644
index 0000000..ab8618e
--- /dev/null
+++ b/drivers/of/of_path.c
@@ -0,0 +1,155 @@
+/*
+ * of_path.c
+ *
+ * Copyright (c) 2013 Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>, Pengutronix
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that 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.
+ *
+ */
+
+#include <common.h>
+#include <malloc.h>
+#include <of.h>
+
+struct of_path {
+ struct cdev *cdev;
+ struct device_d *dev;
+};
+
+struct of_path_type {
+ const char *name;
+ int (*parse)(struct of_path *op, const char *str);
+};
+
+/**
+ * of_path_type_partname - find a partition based on physical device and
+ * partition name
+ * @op: of_path context
+ * @name: the partition name to find
+ */
+static int of_path_type_partname(struct of_path *op, const char *name)
+{
+ if (!op->dev)
+ return -EINVAL;
+
+ op->cdev = device_find_partition(op->dev, name);
+ if (op->cdev) {
+ pr_debug("%s: found part '%s'\n", __func__, name);
+ return 0;
+ } else {
+ pr_debug("%s: cannot find part '%s'\n", __func__, name);
+ return -ENODEV;
+ }
+}
+
+static struct of_path_type of_path_types[] = {
+ {
+ .name = "partname",
+ .parse = of_path_type_partname,
+ },
+};
+
+static int of_path_parse_one(struct of_path *op, const char *str)
+{
+ int i, ret;
+ char *name, *desc;
+
+ pr_debug("parsing: %s\n", str);
+
+ name = xstrdup(str);
+ desc = strchr(name, ':');
+ if (!desc) {
+ free(name);
+ return -EINVAL;
+ }
+
+ *desc = 0;
+ desc++;
+
+ for (i = 0; i < ARRAY_SIZE(of_path_types); i++) {
+ if (!strcmp(of_path_types[i].name, name)) {
+ ret = of_path_types[i].parse(op, desc);
+ goto out;
+ }
+ }
+
+ ret = -EINVAL;
+out:
+ free(name);
+
+ return ret;
+}
+
+/**
+ * of_find_path - translate a path description in the devicetree to a barebox
+ * path
+ *
+ * @node: the node containing the property with the path description
+ * @propname: the property name of the path description
+ * @outpath: if this function returns 0 outpath will contain the path belonging
+ * to the input path description. Must be freed with free().
+ *
+ * pathes in the devicetree have the form of a multistring property. The first
+ * string contains the full path to the physical device containing the path.
+ * The remaining strings have the form "<type>:<options>". Currently supported
+ * for <type> are:
+ *
+ * partname:<partname> - find a partition by its partition name. For mtd
+ * partitions this is the label. For DOS partitions
+ * this is the number beginning with 0.
+ *
+ * examples:
+ *
+ * device-path = &mmc0, "partname:0";
+ * device-path = &norflash, "partname:barebox-environment";
+ */
+int of_find_path(struct device_node *node, const char *propname, char **outpath)
+{
+ struct of_path op = {};
+ struct device_node *rnode;
+ const char *path, *str;
+ int i, len, ret;
+
+ path = of_get_property(node, propname, &len);
+ if (!path)
+ return -EINVAL;
+
+ rnode = of_find_node_by_path(path);
+ if (!rnode)
+ return -ENODEV;
+
+ op.dev = of_find_device_by_node_path(rnode->full_name);
+ if (!op.dev)
+ return -ENODEV;
+
+ device_detect(op.dev);
+
+ i = 1;
+
+ while (1) {
+ ret = of_property_read_string_index(node, propname, i++, &str);
+ if (ret)
+ break;
+
+ ret = of_path_parse_one(&op, str);
+ if (ret)
+ return ret;
+ }
+
+ if (!op.cdev)
+ return -ENOENT;
+
+ *outpath = asprintf("/dev/%s", op.cdev->name);
+
+ return 0;
+}
diff --git a/fs/devfs-core.c b/fs/devfs-core.c
index a92d434..b41ae53 100644
--- a/fs/devfs-core.c
+++ b/fs/devfs-core.c
@@ -244,6 +244,8 @@ int devfs_create(struct cdev *new)
if (new->dev)
list_add_tail(&new->devices_list, &new->dev->cdevs);
+ of_cdev_register(new);
+
return 0;
}
diff --git a/include/driver.h b/include/driver.h
index f95c93c..9abd41c 100644
--- a/include/driver.h
+++ b/include/driver.h
@@ -455,6 +455,11 @@ struct cdev {
struct mtd_info *mtd;
};
+extern struct list_head cdev_list;
+
+#define cdev_for_each(cdev) \
+ list_for_each_entry(cdev, &cdev_list, list)
+
int devfs_create(struct cdev *);
int devfs_remove(struct cdev *);
int cdev_find_free_index(const char *);
diff --git a/include/of.h b/include/of.h
index 710383c..e977e23 100644
--- a/include/of.h
+++ b/include/of.h
@@ -229,6 +229,8 @@ void *of_flatten_dtb(struct device_node *node);
int of_add_memory(struct device_node *node, bool dump);
void of_add_memory_bank(struct device_node *node, bool dump, int r,
u64 base, u64 size);
+struct device_d *of_find_device_by_node_path(const char *path);
+int of_find_path(struct device_node *node, const char *propname, char **outpath);
#else
static inline int of_parse_partitions(struct cdev *cdev,
struct device_node *node)
@@ -560,6 +562,7 @@ static inline struct device_d *of_find_device_by_node(struct device_node *np)
{
return NULL;
}
+
#endif
#define for_each_node_by_name(dn, name) \
@@ -682,4 +685,12 @@ static inline int of_property_write_u64(struct device_node *np,
extern const struct of_device_id of_default_bus_match_table[];
+#ifdef CONFIG_OF_BAREBOX_DRIVERS
+void of_cdev_register(struct cdev *cdev);
+#else
+static inline void of_cdev_register(struct cdev *cdev)
+{
+}
+#endif
+
#endif /* __OF_H */
--
1.8.3.2
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