While we have had our binding for a long time, it was never submitted for upstream inclusion in the Linux DT bindings and it's unlikely to be accepted as there are no other bindings that reference a fixed partition in a property. Linux has support for a u-boot,env binding, which is used by giving the partition a compatible = "u-boot,env" property. Let's support the same thing for barebox and allow barebox,environment to be a subnode of a fixed-partitions node. We intentionally don't add file-path support for now as the intention is to flesh out this binding together with upstream. Signed-off-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx> --- .../bindings/nvmem/barebox,environment.yaml | 55 +++++++++++++++ drivers/of/barebox.c | 67 ++++++++++--------- 2 files changed, 90 insertions(+), 32 deletions(-) create mode 100644 Documentation/devicetree/bindings/nvmem/barebox,environment.yaml diff --git a/Documentation/devicetree/bindings/nvmem/barebox,environment.yaml b/Documentation/devicetree/bindings/nvmem/barebox,environment.yaml new file mode 100644 index 000000000000..9923baa19b40 --- /dev/null +++ b/Documentation/devicetree/bindings/nvmem/barebox,environment.yaml @@ -0,0 +1,55 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://barebox.org/schemas/nvmem/barebox,environment.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: barebox environment variables + +description: | + barebox uses its environment to store non-volatile variables, scripts + and arbitrary binary blobs. + By default, the built-in environment compiled into barebox is used, but + for development purposes, it's possible to override it at runtime. + + Variables can not yet be defined as NVMEM device subnodes. + +maintainers: + - Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx> + +properties: + compatible: + const: barebox,environment + + reg: + maxItems: 1 + +required: + - compatible + - label + - reg + +allOf: + - $ref: partition.yaml# + +additionalProperties: false + +examples: + - | + partitions { + compatible = "fixed-partitions"; + #address-cells = <1>; + #size-cells = <1>; + + partition@0 { + reg = <0x0 0x100000>; + label = "barebox"; + read-only; + }; + + partition@100000 { + compatible = "barebox,environment"; + label = "env"; + reg = <0x100000 0x10000>; + }; + }; diff --git a/drivers/of/barebox.c b/drivers/of/barebox.c index 65392697913b..85e356f5ac0f 100644 --- a/drivers/of/barebox.c +++ b/drivers/of/barebox.c @@ -15,27 +15,38 @@ #define ENV_MNT_DIR "/boot" /* If env on filesystem, where to mount */ -/* If dev describes a file on a fs, mount the fs and return a pointer - * to the file's path. Otherwise return an error code or NULL if the - * device path should be used. - * Does nothing in env in a file support isn't enabled. - */ -static char *environment_check_mount(struct device *dev, const char *devpath) +static char *environment_probe_1node_binding(struct device *dev) +{ + struct cdev *cdev; + + cdev = cdev_by_device_node(dev->of_node); + if (!cdev) + return ERR_PTR(-EINVAL); + + return basprintf("/dev/%s", cdev_name(cdev)); +} + +static char *environment_probe_2node_binding(struct device *dev) { const char *filepath; + char *devpath; int ret; + ret = of_find_path(dev->of_node, "device-path", &devpath, + OF_FIND_PATH_FLAGS_BB); + if (ret) + goto out; + if (!IS_ENABLED(CONFIG_OF_BAREBOX_ENV_IN_FS)) - return NULL; + return devpath; ret = of_property_read_string(dev->of_node, "file-path", &filepath); if (ret == -EINVAL) { - /* No file-path so just use device-path */ - return NULL; + return devpath; } else if (ret) { /* file-path property exists, but has error */ dev_err(dev, "Problem with file-path property\n"); - return ERR_PTR(ret); + goto out; } /* Get device env is on and mount it */ @@ -44,42 +55,34 @@ static char *environment_check_mount(struct device *dev, const char *devpath) if (ret) { dev_err(dev, "Failed to load environment: mount %s failed (%d)\n", devpath, ret); - return ERR_PTR(ret); + goto out; } /* Set env to be in a file on the now mounted device */ dev_dbg(dev, "Loading default env from %s on device %s\n", filepath, devpath); - return basprintf("%s/%s", ENV_MNT_DIR, filepath); +out: + free(devpath); + return ret ? ERR_PTR(ret) : basprintf("%s/%s", ENV_MNT_DIR, filepath); } static int environment_probe(struct device *dev) { - char *devpath, *filepath; - int ret; + char *path; - ret = of_find_path(dev->of_node, "device-path", &devpath, - OF_FIND_PATH_FLAGS_BB); - if (ret) - return ret; - - /* Do we need to mount a fs and find env there? */ - filepath = environment_check_mount(dev, devpath); - if (IS_ERR(filepath)) { - free(devpath); - return ret; - } - - if (filepath) - free(devpath); + if (of_property_present(dev->of_node, "device-path")) + path = environment_probe_2node_binding(dev); else - filepath = devpath; + path = environment_probe_1node_binding(dev); - dev_dbg(dev, "Setting default environment path to %s\n", filepath); - default_environment_path_set(filepath); + if (IS_ERR(path)) + return PTR_ERR(path); - free(filepath); + dev_dbg(dev, "Setting default environment path to %s\n", path); + default_environment_path_set(path); + + free(path); return 0; } -- 2.39.5
