diff options
Diffstat (limited to 'target/linux/generic/backport-5.10/814-v6.4-0002-nvmem-core-introduce-NVMEM-layouts.patch')
-rw-r--r-- | target/linux/generic/backport-5.10/814-v6.4-0002-nvmem-core-introduce-NVMEM-layouts.patch | 387 |
1 files changed, 387 insertions, 0 deletions
diff --git a/target/linux/generic/backport-5.10/814-v6.4-0002-nvmem-core-introduce-NVMEM-layouts.patch b/target/linux/generic/backport-5.10/814-v6.4-0002-nvmem-core-introduce-NVMEM-layouts.patch new file mode 100644 index 0000000000..8b886aea2e --- /dev/null +++ b/target/linux/generic/backport-5.10/814-v6.4-0002-nvmem-core-introduce-NVMEM-layouts.patch @@ -0,0 +1,387 @@ +From 266570f496b90dea8fda893c2cf7c28d63ae2bd9 Mon Sep 17 00:00:00 2001 +From: Michael Walle <michael@walle.cc> +Date: Tue, 4 Apr 2023 18:21:21 +0100 +Subject: [PATCH] nvmem: core: introduce NVMEM layouts + +NVMEM layouts are used to generate NVMEM cells during runtime. Think of +an EEPROM with a well-defined conent. For now, the content can be +described by a device tree or a board file. But this only works if the +offsets and lengths are static and don't change. One could also argue +that putting the layout of the EEPROM in the device tree is the wrong +place. Instead, the device tree should just have a specific compatible +string. + +Right now there are two use cases: + (1) The NVMEM cell needs special processing. E.g. if it only specifies + a base MAC address offset and you need to add an offset, or it + needs to parse a MAC from ASCII format or some proprietary format. + (Post processing of cells is added in a later commit). + (2) u-boot environment parsing. The cells don't have a particular + offset but it needs parsing the content to determine the offsets + and length. + +Co-developed-by: Miquel Raynal <miquel.raynal@bootlin.com> +Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> +Signed-off-by: Michael Walle <michael@walle.cc> +Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> +Link: https://lore.kernel.org/r/20230404172148.82422-14-srinivas.kandagatla@linaro.org +Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> +--- + Documentation/driver-api/nvmem.rst | 15 ++++ + drivers/nvmem/Kconfig | 4 + + drivers/nvmem/Makefile | 1 + + drivers/nvmem/core.c | 120 +++++++++++++++++++++++++++++ + drivers/nvmem/layouts/Kconfig | 5 ++ + drivers/nvmem/layouts/Makefile | 4 + + include/linux/nvmem-consumer.h | 7 ++ + include/linux/nvmem-provider.h | 51 ++++++++++++ + 8 files changed, 207 insertions(+) + create mode 100644 drivers/nvmem/layouts/Kconfig + create mode 100644 drivers/nvmem/layouts/Makefile + +--- a/Documentation/driver-api/nvmem.rst ++++ b/Documentation/driver-api/nvmem.rst +@@ -189,3 +189,18 @@ ex:: + ===================== + + See Documentation/devicetree/bindings/nvmem/nvmem.txt ++ ++8. NVMEM layouts ++================ ++ ++NVMEM layouts are yet another mechanism to create cells. With the device ++tree binding it is possible to specify simple cells by using an offset ++and a length. Sometimes, the cells doesn't have a static offset, but ++the content is still well defined, e.g. tag-length-values. In this case, ++the NVMEM device content has to be first parsed and the cells need to ++be added accordingly. Layouts let you read the content of the NVMEM device ++and let you add cells dynamically. ++ ++Another use case for layouts is the post processing of cells. With layouts, ++it is possible to associate a custom post processing hook to a cell. It ++even possible to add this hook to cells not created by the layout itself. +--- a/drivers/nvmem/Kconfig ++++ b/drivers/nvmem/Kconfig +@@ -21,6 +21,10 @@ config NVMEM_SYSFS + This interface is mostly used by userspace applications to + read/write directly into nvmem. + ++# Layouts ++ ++source "drivers/nvmem/layouts/Kconfig" ++ + # Devices + + config NVMEM_APPLE_EFUSES +--- a/drivers/nvmem/Makefile ++++ b/drivers/nvmem/Makefile +@@ -5,6 +5,7 @@ + + obj-$(CONFIG_NVMEM) += nvmem_core.o + nvmem_core-y := core.o ++obj-y += layouts/ + + # Devices + obj-$(CONFIG_NVMEM_APPLE_EFUSES) += nvmem-apple-efuses.o +--- a/drivers/nvmem/core.c ++++ b/drivers/nvmem/core.c +@@ -40,6 +40,7 @@ struct nvmem_device { + nvmem_reg_write_t reg_write; + nvmem_cell_post_process_t cell_post_process; + struct gpio_desc *wp_gpio; ++ struct nvmem_layout *layout; + void *priv; + }; + +@@ -74,6 +75,9 @@ static LIST_HEAD(nvmem_lookup_list); + + static BLOCKING_NOTIFIER_HEAD(nvmem_notifier); + ++static DEFINE_SPINLOCK(nvmem_layout_lock); ++static LIST_HEAD(nvmem_layouts); ++ + static int __nvmem_reg_read(struct nvmem_device *nvmem, unsigned int offset, + void *val, size_t bytes) + { +@@ -728,6 +732,101 @@ static int nvmem_add_cells_from_of(struc + return 0; + } + ++int __nvmem_layout_register(struct nvmem_layout *layout, struct module *owner) ++{ ++ layout->owner = owner; ++ ++ spin_lock(&nvmem_layout_lock); ++ list_add(&layout->node, &nvmem_layouts); ++ spin_unlock(&nvmem_layout_lock); ++ ++ return 0; ++} ++EXPORT_SYMBOL_GPL(__nvmem_layout_register); ++ ++void nvmem_layout_unregister(struct nvmem_layout *layout) ++{ ++ spin_lock(&nvmem_layout_lock); ++ list_del(&layout->node); ++ spin_unlock(&nvmem_layout_lock); ++} ++EXPORT_SYMBOL_GPL(nvmem_layout_unregister); ++ ++static struct nvmem_layout *nvmem_layout_get(struct nvmem_device *nvmem) ++{ ++ struct device_node *layout_np, *np = nvmem->dev.of_node; ++ struct nvmem_layout *l, *layout = NULL; ++ ++ layout_np = of_get_child_by_name(np, "nvmem-layout"); ++ if (!layout_np) ++ return NULL; ++ ++ spin_lock(&nvmem_layout_lock); ++ ++ list_for_each_entry(l, &nvmem_layouts, node) { ++ if (of_match_node(l->of_match_table, layout_np)) { ++ if (try_module_get(l->owner)) ++ layout = l; ++ ++ break; ++ } ++ } ++ ++ spin_unlock(&nvmem_layout_lock); ++ of_node_put(layout_np); ++ ++ return layout; ++} ++ ++static void nvmem_layout_put(struct nvmem_layout *layout) ++{ ++ if (layout) ++ module_put(layout->owner); ++} ++ ++static int nvmem_add_cells_from_layout(struct nvmem_device *nvmem) ++{ ++ struct nvmem_layout *layout = nvmem->layout; ++ int ret; ++ ++ if (layout && layout->add_cells) { ++ ret = layout->add_cells(&nvmem->dev, nvmem, layout); ++ if (ret) ++ return ret; ++ } ++ ++ return 0; ++} ++ ++#if IS_ENABLED(CONFIG_OF) ++/** ++ * of_nvmem_layout_get_container() - Get OF node to layout container. ++ * ++ * @nvmem: nvmem device. ++ * ++ * Return: a node pointer with refcount incremented or NULL if no ++ * container exists. Use of_node_put() on it when done. ++ */ ++struct device_node *of_nvmem_layout_get_container(struct nvmem_device *nvmem) ++{ ++ return of_get_child_by_name(nvmem->dev.of_node, "nvmem-layout"); ++} ++EXPORT_SYMBOL_GPL(of_nvmem_layout_get_container); ++#endif ++ ++const void *nvmem_layout_get_match_data(struct nvmem_device *nvmem, ++ struct nvmem_layout *layout) ++{ ++ struct device_node __maybe_unused *layout_np; ++ const struct of_device_id *match; ++ ++ layout_np = of_nvmem_layout_get_container(nvmem); ++ match = of_match_node(layout->of_match_table, layout_np); ++ ++ return match ? match->data : NULL; ++} ++EXPORT_SYMBOL_GPL(nvmem_layout_get_match_data); ++ + /** + * nvmem_register() - Register a nvmem device for given nvmem_config. + * Also creates a binary entry in /sys/bus/nvmem/devices/dev-name/nvmem +@@ -834,6 +933,12 @@ struct nvmem_device *nvmem_register(cons + goto err_put_device; + } + ++ /* ++ * If the driver supplied a layout by config->layout, the module ++ * pointer will be NULL and nvmem_layout_put() will be a noop. ++ */ ++ nvmem->layout = config->layout ?: nvmem_layout_get(nvmem); ++ + if (config->cells) { + rval = nvmem_add_cells(nvmem, config->cells, config->ncells); + if (rval) +@@ -854,12 +959,17 @@ struct nvmem_device *nvmem_register(cons + if (rval) + goto err_remove_cells; + ++ rval = nvmem_add_cells_from_layout(nvmem); ++ if (rval) ++ goto err_remove_cells; ++ + blocking_notifier_call_chain(&nvmem_notifier, NVMEM_ADD, nvmem); + + return nvmem; + + err_remove_cells: + nvmem_device_remove_all_cells(nvmem); ++ nvmem_layout_put(nvmem->layout); + if (config->compat) + nvmem_sysfs_remove_compat(nvmem, config); + err_put_device: +@@ -881,6 +991,7 @@ static void nvmem_device_release(struct + device_remove_bin_file(nvmem->base_dev, &nvmem->eeprom); + + nvmem_device_remove_all_cells(nvmem); ++ nvmem_layout_put(nvmem->layout); + device_unregister(&nvmem->dev); + } + +@@ -1246,6 +1357,15 @@ struct nvmem_cell *of_nvmem_cell_get(str + return ERR_PTR(-EINVAL); + } + ++ /* nvmem layouts produce cells within the nvmem-layout container */ ++ if (of_node_name_eq(nvmem_np, "nvmem-layout")) { ++ nvmem_np = of_get_next_parent(nvmem_np); ++ if (!nvmem_np) { ++ of_node_put(cell_np); ++ return ERR_PTR(-EINVAL); ++ } ++ } ++ + nvmem = __nvmem_device_get(nvmem_np, device_match_of_node); + of_node_put(nvmem_np); + if (IS_ERR(nvmem)) { +--- /dev/null ++++ b/drivers/nvmem/layouts/Kconfig +@@ -0,0 +1,5 @@ ++# SPDX-License-Identifier: GPL-2.0 ++ ++menu "Layout Types" ++ ++endmenu +--- /dev/null ++++ b/drivers/nvmem/layouts/Makefile +@@ -0,0 +1,4 @@ ++# SPDX-License-Identifier: GPL-2.0 ++# ++# Makefile for nvmem layouts. ++# +--- a/include/linux/nvmem-consumer.h ++++ b/include/linux/nvmem-consumer.h +@@ -225,6 +225,7 @@ struct nvmem_cell *of_nvmem_cell_get(str + const char *id); + struct nvmem_device *of_nvmem_device_get(struct device_node *np, + const char *name); ++struct device_node *of_nvmem_layout_get_container(struct nvmem_device *nvmem); + #else + static inline struct nvmem_cell *of_nvmem_cell_get(struct device_node *np, + const char *id) +@@ -237,6 +238,12 @@ static inline struct nvmem_device *of_nv + { + return ERR_PTR(-EOPNOTSUPP); + } ++ ++static inline struct device_node * ++of_nvmem_layout_get_container(struct nvmem_device *nvmem) ++{ ++ return ERR_PTR(-EOPNOTSUPP); ++} + #endif /* CONFIG_NVMEM && CONFIG_OF */ + + #endif /* ifndef _LINUX_NVMEM_CONSUMER_H */ +--- a/include/linux/nvmem-provider.h ++++ b/include/linux/nvmem-provider.h +@@ -88,6 +88,7 @@ struct nvmem_cell_info { + * @stride: Minimum read/write access stride. + * @priv: User context passed to read/write callbacks. + * @ignore_wp: Write Protect pin is managed by the provider. ++ * @layout: Fixed layout associated with this nvmem device. + * + * Note: A default "nvmem<id>" name will be assigned to the device if + * no name is specified in its configuration. In such case "<id>" is +@@ -110,6 +111,7 @@ struct nvmem_config { + bool root_only; + struct device_node *of_node; + bool ignore_wp; ++ struct nvmem_layout *layout; + bool no_of_node; + nvmem_reg_read_t reg_read; + nvmem_reg_write_t reg_write; +@@ -142,6 +144,33 @@ struct nvmem_cell_table { + struct list_head node; + }; + ++/** ++ * struct nvmem_layout - NVMEM layout definitions ++ * ++ * @name: Layout name. ++ * @of_match_table: Open firmware match table. ++ * @add_cells: Will be called if a nvmem device is found which ++ * has this layout. The function will add layout ++ * specific cells with nvmem_add_one_cell(). ++ * @owner: Pointer to struct module. ++ * @node: List node. ++ * ++ * A nvmem device can hold a well defined structure which can just be ++ * evaluated during runtime. For example a TLV list, or a list of "name=val" ++ * pairs. A nvmem layout can parse the nvmem device and add appropriate ++ * cells. ++ */ ++struct nvmem_layout { ++ const char *name; ++ const struct of_device_id *of_match_table; ++ int (*add_cells)(struct device *dev, struct nvmem_device *nvmem, ++ struct nvmem_layout *layout); ++ ++ /* private */ ++ struct module *owner; ++ struct list_head node; ++}; ++ + #if IS_ENABLED(CONFIG_NVMEM) + + struct nvmem_device *nvmem_register(const struct nvmem_config *cfg); +@@ -156,6 +185,14 @@ void nvmem_del_cell_table(struct nvmem_c + int nvmem_add_one_cell(struct nvmem_device *nvmem, + const struct nvmem_cell_info *info); + ++int __nvmem_layout_register(struct nvmem_layout *layout, struct module *owner); ++#define nvmem_layout_register(layout) \ ++ __nvmem_layout_register(layout, THIS_MODULE) ++void nvmem_layout_unregister(struct nvmem_layout *layout); ++ ++const void *nvmem_layout_get_match_data(struct nvmem_device *nvmem, ++ struct nvmem_layout *layout); ++ + #else + + static inline struct nvmem_device *nvmem_register(const struct nvmem_config *c) +@@ -179,5 +216,19 @@ static inline int nvmem_add_one_cell(str + return -EOPNOTSUPP; + } + ++static inline int nvmem_layout_register(struct nvmem_layout *layout) ++{ ++ return -EOPNOTSUPP; ++} ++ ++static inline void nvmem_layout_unregister(struct nvmem_layout *layout) {} ++ ++static inline const void * ++nvmem_layout_get_match_data(struct nvmem_device *nvmem, ++ struct nvmem_layout *layout) ++{ ++ return NULL; ++} ++ + #endif /* CONFIG_NVMEM */ + #endif /* ifndef _LINUX_NVMEM_PROVIDER_H */ |