2023-12-15 11:16:35

by Srinivas Kandagatla

[permalink] [raw]
Subject: [PATCH 00/10] nvmem: patches for v6.8

From: Srinivas Kandagatla <[email protected]>

Here are some nvmem patches for 6.8 that includes

- sysfs support for nvmem cells.
- layout rework.
- add stm32mp25 provider support.

Can you please queue them up for 6.8.

Thanks,
Srini


Miquel Raynal (8):
of: device: Export of_device_make_bus_id()
nvmem: Move of_nvmem_layout_get_container() in another header
nvmem: Create a header for internal sharing
nvmem: Simplify the ->add_cells() hook
nvmem: Move and rename ->fixup_cell_info()
nvmem: core: Rework layouts to become regular devices
ABI: sysfs-nvmem-cells: Expose cells through sysfs
nvmem: core: Expose cells through sysfs

Patrick Delaunay (2):
dt-bindings: nvmem: add new stm32mp25 compatible for stm32-romem
nvmem: stm32: add support for STM32MP25 BSEC to control OTP data

Documentation/ABI/testing/sysfs-nvmem-cells | 21 ++
.../bindings/nvmem/st,stm32-romem.yaml | 1 +
drivers/nvmem/Kconfig | 1 +
drivers/nvmem/Makefile | 2 +
drivers/nvmem/core.c | 335 ++++++++++--------
drivers/nvmem/imx-ocotp.c | 11 +-
drivers/nvmem/internals.h | 59 +++
drivers/nvmem/layouts.c | 201 +++++++++++
drivers/nvmem/layouts/Kconfig | 8 +
drivers/nvmem/layouts/onie-tlv.c | 27 +-
drivers/nvmem/layouts/sl28vpd.c | 27 +-
drivers/nvmem/mtk-efuse.c | 11 +-
drivers/nvmem/stm32-romem.c | 16 +
drivers/of/device.c | 41 +++
drivers/of/platform.c | 40 ---
include/linux/nvmem-consumer.h | 7 -
include/linux/nvmem-provider.h | 66 ++--
include/linux/of_device.h | 6 +
18 files changed, 642 insertions(+), 238 deletions(-)
create mode 100644 Documentation/ABI/testing/sysfs-nvmem-cells
create mode 100644 drivers/nvmem/internals.h
create mode 100644 drivers/nvmem/layouts.c

--
2.25.1



2023-12-15 11:16:40

by Srinivas Kandagatla

[permalink] [raw]
Subject: [PATCH 04/10] nvmem: Simplify the ->add_cells() hook

From: Miquel Raynal <[email protected]>

The layout entry is not used and will anyway be made useless by the new
layout bus infrastructure coming next, so drop it. While at it, clarify
the kdoc entry.

Signed-off-by: Miquel Raynal <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
---
drivers/nvmem/core.c | 2 +-
drivers/nvmem/layouts/onie-tlv.c | 3 +--
drivers/nvmem/layouts/sl28vpd.c | 3 +--
include/linux/nvmem-provider.h | 8 +++-----
4 files changed, 6 insertions(+), 10 deletions(-)

diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index b5e5ce67398f..f63db5e01fca 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -816,7 +816,7 @@ static int nvmem_add_cells_from_layout(struct nvmem_device *nvmem)
int ret;

if (layout && layout->add_cells) {
- ret = layout->add_cells(&nvmem->dev, nvmem, layout);
+ ret = layout->add_cells(&nvmem->dev, nvmem);
if (ret)
return ret;
}
diff --git a/drivers/nvmem/layouts/onie-tlv.c b/drivers/nvmem/layouts/onie-tlv.c
index 59fc87ccfcff..defd42d4375c 100644
--- a/drivers/nvmem/layouts/onie-tlv.c
+++ b/drivers/nvmem/layouts/onie-tlv.c
@@ -182,8 +182,7 @@ static bool onie_tlv_crc_is_valid(struct device *dev, size_t table_len, u8 *tabl
return true;
}

-static int onie_tlv_parse_table(struct device *dev, struct nvmem_device *nvmem,
- struct nvmem_layout *layout)
+static int onie_tlv_parse_table(struct device *dev, struct nvmem_device *nvmem)
{
struct onie_tlv_hdr hdr;
size_t table_len, data_len, hdr_len;
diff --git a/drivers/nvmem/layouts/sl28vpd.c b/drivers/nvmem/layouts/sl28vpd.c
index 05671371f631..26c7cf21b523 100644
--- a/drivers/nvmem/layouts/sl28vpd.c
+++ b/drivers/nvmem/layouts/sl28vpd.c
@@ -80,8 +80,7 @@ static int sl28vpd_v1_check_crc(struct device *dev, struct nvmem_device *nvmem)
return 0;
}

-static int sl28vpd_add_cells(struct device *dev, struct nvmem_device *nvmem,
- struct nvmem_layout *layout)
+static int sl28vpd_add_cells(struct device *dev, struct nvmem_device *nvmem)
{
const struct nvmem_cell_info *pinfo;
struct nvmem_cell_info info = {0};
diff --git a/include/linux/nvmem-provider.h b/include/linux/nvmem-provider.h
index e5de21516387..3939991b3c5f 100644
--- a/include/linux/nvmem-provider.h
+++ b/include/linux/nvmem-provider.h
@@ -156,9 +156,8 @@ struct nvmem_cell_table {
*
* @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().
+ * @add_cells: Called to populate the layout using
+ * nvmem_add_one_cell().
* @fixup_cell_info: Will be called before a cell is added. Can be
* used to modify the nvmem_cell_info.
* @owner: Pointer to struct module.
@@ -172,8 +171,7 @@ struct nvmem_cell_table {
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);
+ int (*add_cells)(struct device *dev, struct nvmem_device *nvmem);
void (*fixup_cell_info)(struct nvmem_device *nvmem,
struct nvmem_layout *layout,
struct nvmem_cell_info *cell);
--
2.25.1


2023-12-15 11:16:51

by Srinivas Kandagatla

[permalink] [raw]
Subject: [PATCH 01/10] of: device: Export of_device_make_bus_id()

From: Miquel Raynal <[email protected]>

This helper is really handy to create unique device names based on their
device tree path, we may need it outside of the OF core (in the NVMEM
subsystem) so let's export it. As this helper has nothing patform
specific, let's move it to of/device.c instead of of/platform.c so we
can add its prototype to of_device.h.

Signed-off-by: Miquel Raynal <[email protected]>
Acked-by: Rob Herring <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
---
drivers/of/device.c | 41 +++++++++++++++++++++++++++++++++++++++
drivers/of/platform.c | 40 --------------------------------------
include/linux/of_device.h | 6 ++++++
3 files changed, 47 insertions(+), 40 deletions(-)

diff --git a/drivers/of/device.c b/drivers/of/device.c
index 1ca42ad9dd15..6e9572c4af83 100644
--- a/drivers/of/device.c
+++ b/drivers/of/device.c
@@ -304,3 +304,44 @@ int of_device_uevent_modalias(const struct device *dev, struct kobj_uevent_env *
return 0;
}
EXPORT_SYMBOL_GPL(of_device_uevent_modalias);
+
+/**
+ * of_device_make_bus_id - Use the device node data to assign a unique name
+ * @dev: pointer to device structure that is linked to a device tree node
+ *
+ * This routine will first try using the translated bus address to
+ * derive a unique name. If it cannot, then it will prepend names from
+ * parent nodes until a unique name can be derived.
+ */
+void of_device_make_bus_id(struct device *dev)
+{
+ struct device_node *node = dev->of_node;
+ const __be32 *reg;
+ u64 addr;
+ u32 mask;
+
+ /* Construct the name, using parent nodes if necessary to ensure uniqueness */
+ while (node->parent) {
+ /*
+ * If the address can be translated, then that is as much
+ * uniqueness as we need. Make it the first component and return
+ */
+ reg = of_get_property(node, "reg", NULL);
+ if (reg && (addr = of_translate_address(node, reg)) != OF_BAD_ADDR) {
+ if (!of_property_read_u32(node, "mask", &mask))
+ dev_set_name(dev, dev_name(dev) ? "%llx.%x.%pOFn:%s" : "%llx.%x.%pOFn",
+ addr, ffs(mask) - 1, node, dev_name(dev));
+
+ else
+ dev_set_name(dev, dev_name(dev) ? "%llx.%pOFn:%s" : "%llx.%pOFn",
+ addr, node, dev_name(dev));
+ return;
+ }
+
+ /* format arguments only used if dev_name() resolves to NULL */
+ dev_set_name(dev, dev_name(dev) ? "%s:%s" : "%s",
+ kbasename(node->full_name), dev_name(dev));
+ node = node->parent;
+ }
+}
+EXPORT_SYMBOL_GPL(of_device_make_bus_id);
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 126d265aa7d8..c39e49a1eba0 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -97,46 +97,6 @@ static const struct of_device_id of_skipped_node_table[] = {
* mechanism for creating devices from device tree nodes.
*/

-/**
- * of_device_make_bus_id - Use the device node data to assign a unique name
- * @dev: pointer to device structure that is linked to a device tree node
- *
- * This routine will first try using the translated bus address to
- * derive a unique name. If it cannot, then it will prepend names from
- * parent nodes until a unique name can be derived.
- */
-static void of_device_make_bus_id(struct device *dev)
-{
- struct device_node *node = dev->of_node;
- const __be32 *reg;
- u64 addr;
- u32 mask;
-
- /* Construct the name, using parent nodes if necessary to ensure uniqueness */
- while (node->parent) {
- /*
- * If the address can be translated, then that is as much
- * uniqueness as we need. Make it the first component and return
- */
- reg = of_get_property(node, "reg", NULL);
- if (reg && (addr = of_translate_address(node, reg)) != OF_BAD_ADDR) {
- if (!of_property_read_u32(node, "mask", &mask))
- dev_set_name(dev, dev_name(dev) ? "%llx.%x.%pOFn:%s" : "%llx.%x.%pOFn",
- addr, ffs(mask) - 1, node, dev_name(dev));
-
- else
- dev_set_name(dev, dev_name(dev) ? "%llx.%pOFn:%s" : "%llx.%pOFn",
- addr, node, dev_name(dev));
- return;
- }
-
- /* format arguments only used if dev_name() resolves to NULL */
- dev_set_name(dev, dev_name(dev) ? "%s:%s" : "%s",
- kbasename(node->full_name), dev_name(dev));
- node = node->parent;
- }
-}
-
/**
* of_device_alloc - Allocate and initialize an of_device
* @np: device node to assign to device
diff --git a/include/linux/of_device.h b/include/linux/of_device.h
index 2c7a3d4bc775..a72661e47faa 100644
--- a/include/linux/of_device.h
+++ b/include/linux/of_device.h
@@ -40,6 +40,9 @@ static inline int of_dma_configure(struct device *dev,
{
return of_dma_configure_id(dev, np, force_dma, NULL);
}
+
+void of_device_make_bus_id(struct device *dev);
+
#else /* CONFIG_OF */

static inline int of_driver_match_device(struct device *dev,
@@ -82,6 +85,9 @@ static inline int of_dma_configure(struct device *dev,
{
return 0;
}
+
+static inline void of_device_make_bus_id(struct device *dev) {}
+
#endif /* CONFIG_OF */

#endif /* _LINUX_OF_DEVICE_H */
--
2.25.1


2023-12-15 11:17:01

by Srinivas Kandagatla

[permalink] [raw]
Subject: [PATCH 02/10] nvmem: Move of_nvmem_layout_get_container() in another header

From: Miquel Raynal <[email protected]>

nvmem-consumer.h is included by consumer devices, extracting data from
NVMEM devices whereas nvmem-provider.h is included by devices providing
NVMEM content.

The only users of of_nvmem_layout_get_container() outside of the core
are layout drivers, so better move its prototype to nvmem-provider.h.

While we do so, we also move the kdoc associated with the function to
the header rather than the .c file.

Signed-off-by: Miquel Raynal <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
---
drivers/nvmem/core.c | 8 --------
include/linux/nvmem-consumer.h | 7 -------
include/linux/nvmem-provider.h | 21 +++++++++++++++++++++
3 files changed, 21 insertions(+), 15 deletions(-)

diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index 608b352a7d91..b5b6ec8e04bb 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -847,14 +847,6 @@ static int nvmem_add_cells_from_layout(struct nvmem_device *nvmem)
}

#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");
diff --git a/include/linux/nvmem-consumer.h b/include/linux/nvmem-consumer.h
index 6ec4b9743e25..2d306fa13b1a 100644
--- a/include/linux/nvmem-consumer.h
+++ b/include/linux/nvmem-consumer.h
@@ -247,7 +247,6 @@ struct nvmem_cell *of_nvmem_cell_get(struct device_node *np,
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)
@@ -260,12 +259,6 @@ static inline struct nvmem_device *of_nvmem_device_get(struct device_node *np,
{
return ERR_PTR(-EOPNOTSUPP);
}
-
-static inline struct device_node *
-of_nvmem_layout_get_container(struct nvmem_device *nvmem)
-{
- return NULL;
-}
#endif /* CONFIG_NVMEM && CONFIG_OF */

#endif /* ifndef _LINUX_NVMEM_CONSUMER_H */
diff --git a/include/linux/nvmem-provider.h b/include/linux/nvmem-provider.h
index e3930835235b..e5de21516387 100644
--- a/include/linux/nvmem-provider.h
+++ b/include/linux/nvmem-provider.h
@@ -244,6 +244,27 @@ nvmem_layout_get_match_data(struct nvmem_device *nvmem,

#endif /* CONFIG_NVMEM */

+#if IS_ENABLED(CONFIG_NVMEM) && IS_ENABLED(CONFIG_OF)
+
+/**
+ * of_nvmem_layout_get_container() - Get OF node of 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);
+
+#else /* CONFIG_NVMEM && CONFIG_OF */
+
+static inline struct device_node *of_nvmem_layout_get_container(struct nvmem_device *nvmem)
+{
+ return NULL;
+}
+
+#endif /* CONFIG_NVMEM && CONFIG_OF */
+
#define module_nvmem_layout_driver(__layout_driver) \
module_driver(__layout_driver, nvmem_layout_register, \
nvmem_layout_unregister)
--
2.25.1


2023-12-15 11:17:21

by Srinivas Kandagatla

[permalink] [raw]
Subject: [PATCH 03/10] nvmem: Create a header for internal sharing

From: Miquel Raynal <[email protected]>

Before adding all the NVMEM layout bus infrastructure to the core, let's
move the main nvmem_device structure in an internal header, only
available to the core. This way all the additional code can be added in
a dedicated file in order to keep the current core file tidy.

Signed-off-by: Miquel Raynal <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
---
drivers/nvmem/core.c | 24 +-----------------------
drivers/nvmem/internals.h | 35 +++++++++++++++++++++++++++++++++++
2 files changed, 36 insertions(+), 23 deletions(-)
create mode 100644 drivers/nvmem/internals.h

diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index b5b6ec8e04bb..b5e5ce67398f 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -19,29 +19,7 @@
#include <linux/of.h>
#include <linux/slab.h>

-struct nvmem_device {
- struct module *owner;
- struct device dev;
- int stride;
- int word_size;
- int id;
- struct kref refcnt;
- size_t size;
- bool read_only;
- bool root_only;
- int flags;
- enum nvmem_type type;
- struct bin_attribute eeprom;
- struct device *base_dev;
- struct list_head cells;
- const struct nvmem_keepout *keepout;
- unsigned int nkeepout;
- nvmem_reg_read_t reg_read;
- nvmem_reg_write_t reg_write;
- struct gpio_desc *wp_gpio;
- struct nvmem_layout *layout;
- void *priv;
-};
+#include "internals.h"

#define to_nvmem_device(d) container_of(d, struct nvmem_device, dev)

diff --git a/drivers/nvmem/internals.h b/drivers/nvmem/internals.h
new file mode 100644
index 000000000000..ce353831cd65
--- /dev/null
+++ b/drivers/nvmem/internals.h
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _LINUX_NVMEM_INTERNALS_H
+#define _LINUX_NVMEM_INTERNALS_H
+
+#include <linux/device.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/nvmem-provider.h>
+
+struct nvmem_device {
+ struct module *owner;
+ struct device dev;
+ struct list_head node;
+ int stride;
+ int word_size;
+ int id;
+ struct kref refcnt;
+ size_t size;
+ bool read_only;
+ bool root_only;
+ int flags;
+ enum nvmem_type type;
+ struct bin_attribute eeprom;
+ struct device *base_dev;
+ struct list_head cells;
+ const struct nvmem_keepout *keepout;
+ unsigned int nkeepout;
+ nvmem_reg_read_t reg_read;
+ nvmem_reg_write_t reg_write;
+ struct gpio_desc *wp_gpio;
+ struct nvmem_layout *layout;
+ void *priv;
+};
+
+#endif /* ifndef _LINUX_NVMEM_INTERNALS_H */
--
2.25.1


2023-12-15 11:17:34

by Srinivas Kandagatla

[permalink] [raw]
Subject: [PATCH 05/10] nvmem: Move and rename ->fixup_cell_info()

From: Miquel Raynal <[email protected]>

This hook is meant to be used by any provider and instantiating a layout
just for this is useless. Let's instead move this hook to the nvmem
device and add it to the config structure to be easily shared by the
providers.

While at moving this hook, rename it ->fixup_dt_cell_info() to clarify
its main intended purpose.

Signed-off-by: Miquel Raynal <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
---
drivers/nvmem/core.c | 6 +++---
drivers/nvmem/imx-ocotp.c | 11 +++--------
drivers/nvmem/internals.h | 2 ++
drivers/nvmem/mtk-efuse.c | 11 +++--------
include/linux/nvmem-provider.h | 9 ++++-----
5 files changed, 15 insertions(+), 24 deletions(-)

diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index f63db5e01fca..a885713d6b4b 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -675,7 +675,6 @@ static int nvmem_validate_keepouts(struct nvmem_device *nvmem)

static int nvmem_add_cells_from_dt(struct nvmem_device *nvmem, struct device_node *np)
{
- struct nvmem_layout *layout = nvmem->layout;
struct device *dev = &nvmem->dev;
struct device_node *child;
const __be32 *addr;
@@ -705,8 +704,8 @@ static int nvmem_add_cells_from_dt(struct nvmem_device *nvmem, struct device_nod

info.np = of_node_get(child);

- if (layout && layout->fixup_cell_info)
- layout->fixup_cell_info(nvmem, layout, &info);
+ if (nvmem->fixup_dt_cell_info)
+ nvmem->fixup_dt_cell_info(nvmem, &info);

ret = nvmem_add_one_cell(nvmem, &info);
kfree(info.name);
@@ -895,6 +894,7 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config)

kref_init(&nvmem->refcnt);
INIT_LIST_HEAD(&nvmem->cells);
+ nvmem->fixup_dt_cell_info = config->fixup_dt_cell_info;

nvmem->owner = config->owner;
if (!nvmem->owner && config->dev->driver)
diff --git a/drivers/nvmem/imx-ocotp.c b/drivers/nvmem/imx-ocotp.c
index f1e202efaa49..79dd4fda0329 100644
--- a/drivers/nvmem/imx-ocotp.c
+++ b/drivers/nvmem/imx-ocotp.c
@@ -583,17 +583,12 @@ static const struct of_device_id imx_ocotp_dt_ids[] = {
};
MODULE_DEVICE_TABLE(of, imx_ocotp_dt_ids);

-static void imx_ocotp_fixup_cell_info(struct nvmem_device *nvmem,
- struct nvmem_layout *layout,
- struct nvmem_cell_info *cell)
+static void imx_ocotp_fixup_dt_cell_info(struct nvmem_device *nvmem,
+ struct nvmem_cell_info *cell)
{
cell->read_post_process = imx_ocotp_cell_pp;
}

-static struct nvmem_layout imx_ocotp_layout = {
- .fixup_cell_info = imx_ocotp_fixup_cell_info,
-};
-
static int imx_ocotp_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@@ -619,7 +614,7 @@ static int imx_ocotp_probe(struct platform_device *pdev)
imx_ocotp_nvmem_config.size = 4 * priv->params->nregs;
imx_ocotp_nvmem_config.dev = dev;
imx_ocotp_nvmem_config.priv = priv;
- imx_ocotp_nvmem_config.layout = &imx_ocotp_layout;
+ imx_ocotp_nvmem_config.fixup_dt_cell_info = &imx_ocotp_fixup_dt_cell_info;

priv->config = &imx_ocotp_nvmem_config;

diff --git a/drivers/nvmem/internals.h b/drivers/nvmem/internals.h
index ce353831cd65..893553fbdf51 100644
--- a/drivers/nvmem/internals.h
+++ b/drivers/nvmem/internals.h
@@ -23,6 +23,8 @@ struct nvmem_device {
struct bin_attribute eeprom;
struct device *base_dev;
struct list_head cells;
+ void (*fixup_dt_cell_info)(struct nvmem_device *nvmem,
+ struct nvmem_cell_info *cell);
const struct nvmem_keepout *keepout;
unsigned int nkeepout;
nvmem_reg_read_t reg_read;
diff --git a/drivers/nvmem/mtk-efuse.c b/drivers/nvmem/mtk-efuse.c
index 87c94686cfd2..84f05b40a411 100644
--- a/drivers/nvmem/mtk-efuse.c
+++ b/drivers/nvmem/mtk-efuse.c
@@ -45,9 +45,8 @@ static int mtk_efuse_gpu_speedbin_pp(void *context, const char *id, int index,
return 0;
}

-static void mtk_efuse_fixup_cell_info(struct nvmem_device *nvmem,
- struct nvmem_layout *layout,
- struct nvmem_cell_info *cell)
+static void mtk_efuse_fixup_dt_cell_info(struct nvmem_device *nvmem,
+ struct nvmem_cell_info *cell)
{
size_t sz = strlen(cell->name);

@@ -61,10 +60,6 @@ static void mtk_efuse_fixup_cell_info(struct nvmem_device *nvmem,
cell->read_post_process = mtk_efuse_gpu_speedbin_pp;
}

-static struct nvmem_layout mtk_efuse_layout = {
- .fixup_cell_info = mtk_efuse_fixup_cell_info,
-};
-
static int mtk_efuse_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@@ -91,7 +86,7 @@ static int mtk_efuse_probe(struct platform_device *pdev)
econfig.priv = priv;
econfig.dev = dev;
if (pdata->uses_post_processing)
- econfig.layout = &mtk_efuse_layout;
+ econfig.fixup_dt_cell_info = &mtk_efuse_fixup_dt_cell_info;
nvmem = devm_nvmem_register(dev, &econfig);

return PTR_ERR_OR_ZERO(nvmem);
diff --git a/include/linux/nvmem-provider.h b/include/linux/nvmem-provider.h
index 3939991b3c5f..36415a602d9e 100644
--- a/include/linux/nvmem-provider.h
+++ b/include/linux/nvmem-provider.h
@@ -83,6 +83,8 @@ struct nvmem_cell_info {
* @cells: Optional array of pre-defined NVMEM cells.
* @ncells: Number of elements in cells.
* @add_legacy_fixed_of_cells: Read fixed NVMEM cells from old OF syntax.
+ * @fixup_dt_cell_info: Will be called before a cell is added. Can be
+ * used to modify the nvmem_cell_info.
* @keepout: Optional array of keepout ranges (sorted ascending by start).
* @nkeepout: Number of elements in the keepout array.
* @type: Type of the nvmem storage
@@ -113,6 +115,8 @@ struct nvmem_config {
const struct nvmem_cell_info *cells;
int ncells;
bool add_legacy_fixed_of_cells;
+ void (*fixup_dt_cell_info)(struct nvmem_device *nvmem,
+ struct nvmem_cell_info *cell);
const struct nvmem_keepout *keepout;
unsigned int nkeepout;
enum nvmem_type type;
@@ -158,8 +162,6 @@ struct nvmem_cell_table {
* @of_match_table: Open firmware match table.
* @add_cells: Called to populate the layout using
* nvmem_add_one_cell().
- * @fixup_cell_info: Will be called before a cell is added. Can be
- * used to modify the nvmem_cell_info.
* @owner: Pointer to struct module.
* @node: List node.
*
@@ -172,9 +174,6 @@ struct nvmem_layout {
const char *name;
const struct of_device_id *of_match_table;
int (*add_cells)(struct device *dev, struct nvmem_device *nvmem);
- void (*fixup_cell_info)(struct nvmem_device *nvmem,
- struct nvmem_layout *layout,
- struct nvmem_cell_info *cell);

/* private */
struct module *owner;
--
2.25.1


2023-12-15 11:17:47

by Srinivas Kandagatla

[permalink] [raw]
Subject: [PATCH 08/10] nvmem: core: Expose cells through sysfs

From: Miquel Raynal <[email protected]>

The binary content of nvmem devices is available to the user so in the
easiest cases, finding the content of a cell is rather easy as it is
just a matter of looking at a known and fixed offset. However, nvmem
layouts have been recently introduced to cope with more advanced
situations, where the offset and size of the cells is not known in
advance or is dynamic. When using layouts, more advanced parsers are
used by the kernel in order to give direct access to the content of each
cell, regardless of its position/size in the underlying
device. Unfortunately, these information are not accessible by users,
unless by fully re-implementing the parser logic in userland.

Let's expose the cells and their content through sysfs to avoid these
situations. Of course the relevant NVMEM sysfs Kconfig option must be
enabled for this support to be available.

Not all nvmem devices expose cells. Indeed, the .bin_attrs attribute
group member will be filled at runtime only when relevant and will
remain empty otherwise. In this case, as the cells attribute group will
be empty, it will not lead to any additional folder/file creation.

Exposed cells are read-only. There is, in practice, everything in the
core to support a write path, but as I don't see any need for that, I
prefer to keep the interface simple (and probably safer). The interface
is documented as being in the "testing" state which means we can later
add a write attribute if though relevant.

Signed-off-by: Miquel Raynal <[email protected]>
Tested-by: Rafał Miłecki <[email protected]>
Tested-by: Chen-Yu Tsai <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
---
drivers/nvmem/core.c | 135 +++++++++++++++++++++++++++++++++++++-
drivers/nvmem/internals.h | 1 +
2 files changed, 135 insertions(+), 1 deletion(-)

diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index 4c2154ddf8a7..ba559e81f77f 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -299,6 +299,43 @@ static umode_t nvmem_bin_attr_is_visible(struct kobject *kobj,
return nvmem_bin_attr_get_umode(nvmem);
}

+static struct nvmem_cell *nvmem_create_cell(struct nvmem_cell_entry *entry,
+ const char *id, int index);
+
+static ssize_t nvmem_cell_attr_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *attr, char *buf,
+ loff_t pos, size_t count)
+{
+ struct nvmem_cell_entry *entry;
+ struct nvmem_cell *cell = NULL;
+ size_t cell_sz, read_len;
+ void *content;
+
+ entry = attr->private;
+ cell = nvmem_create_cell(entry, entry->name, 0);
+ if (IS_ERR(cell))
+ return PTR_ERR(cell);
+
+ if (!cell)
+ return -EINVAL;
+
+ content = nvmem_cell_read(cell, &cell_sz);
+ if (IS_ERR(content)) {
+ read_len = PTR_ERR(content);
+ goto destroy_cell;
+ }
+
+ read_len = min_t(unsigned int, cell_sz - pos, count);
+ memcpy(buf, content + pos, read_len);
+ kfree(content);
+
+destroy_cell:
+ kfree_const(cell->id);
+ kfree(cell);
+
+ return read_len;
+}
+
/* default read/write permissions */
static struct bin_attribute bin_attr_rw_nvmem = {
.attr = {
@@ -320,11 +357,21 @@ static const struct attribute_group nvmem_bin_group = {
.is_bin_visible = nvmem_bin_attr_is_visible,
};

+/* Cell attributes will be dynamically allocated */
+static struct attribute_group nvmem_cells_group = {
+ .name = "cells",
+};
+
static const struct attribute_group *nvmem_dev_groups[] = {
&nvmem_bin_group,
NULL,
};

+static const struct attribute_group *nvmem_cells_groups[] = {
+ &nvmem_cells_group,
+ NULL,
+};
+
static struct bin_attribute bin_attr_nvmem_eeprom_compat = {
.attr = {
.name = "eeprom",
@@ -380,6 +427,68 @@ static void nvmem_sysfs_remove_compat(struct nvmem_device *nvmem,
device_remove_bin_file(nvmem->base_dev, &nvmem->eeprom);
}

+static int nvmem_populate_sysfs_cells(struct nvmem_device *nvmem)
+{
+ struct bin_attribute **cells_attrs, *attrs;
+ struct nvmem_cell_entry *entry;
+ unsigned int ncells = 0, i = 0;
+ int ret = 0;
+
+ mutex_lock(&nvmem_mutex);
+
+ if (list_empty(&nvmem->cells) || nvmem->sysfs_cells_populated) {
+ nvmem_cells_group.bin_attrs = NULL;
+ goto unlock_mutex;
+ }
+
+ /* Allocate an array of attributes with a sentinel */
+ ncells = list_count_nodes(&nvmem->cells);
+ cells_attrs = devm_kcalloc(&nvmem->dev, ncells + 1,
+ sizeof(struct bin_attribute *), GFP_KERNEL);
+ if (!cells_attrs) {
+ ret = -ENOMEM;
+ goto unlock_mutex;
+ }
+
+ attrs = devm_kcalloc(&nvmem->dev, ncells, sizeof(struct bin_attribute), GFP_KERNEL);
+ if (!attrs) {
+ ret = -ENOMEM;
+ goto unlock_mutex;
+ }
+
+ /* Initialize each attribute to take the name and size of the cell */
+ list_for_each_entry(entry, &nvmem->cells, node) {
+ sysfs_bin_attr_init(&attrs[i]);
+ attrs[i].attr.name = devm_kasprintf(&nvmem->dev, GFP_KERNEL,
+ "%s@%x", entry->name,
+ entry->offset);
+ attrs[i].attr.mode = 0444;
+ attrs[i].size = entry->bytes;
+ attrs[i].read = &nvmem_cell_attr_read;
+ attrs[i].private = entry;
+ if (!attrs[i].attr.name) {
+ ret = -ENOMEM;
+ goto unlock_mutex;
+ }
+
+ cells_attrs[i] = &attrs[i];
+ i++;
+ }
+
+ nvmem_cells_group.bin_attrs = cells_attrs;
+
+ ret = devm_device_add_groups(&nvmem->dev, nvmem_cells_groups);
+ if (ret)
+ goto unlock_mutex;
+
+ nvmem->sysfs_cells_populated = true;
+
+unlock_mutex:
+ mutex_unlock(&nvmem_mutex);
+
+ return ret;
+}
+
#else /* CONFIG_NVMEM_SYSFS */

static int nvmem_sysfs_setup_compat(struct nvmem_device *nvmem,
@@ -739,11 +848,25 @@ static int nvmem_add_cells_from_fixed_layout(struct nvmem_device *nvmem)

int nvmem_layout_register(struct nvmem_layout *layout)
{
+ int ret;
+
if (!layout->add_cells)
return -EINVAL;

/* Populate the cells */
- return layout->add_cells(&layout->nvmem->dev, layout->nvmem);
+ ret = layout->add_cells(&layout->nvmem->dev, layout->nvmem);
+ if (ret)
+ return ret;
+
+#ifdef CONFIG_NVMEM_SYSFS
+ ret = nvmem_populate_sysfs_cells(layout->nvmem);
+ if (ret) {
+ nvmem_device_remove_all_cells(layout->nvmem);
+ return ret;
+ }
+#endif
+
+ return 0;
}
EXPORT_SYMBOL_GPL(nvmem_layout_register);

@@ -902,10 +1025,20 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config)
if (rval)
goto err_remove_dev;

+#ifdef CONFIG_NVMEM_SYSFS
+ rval = nvmem_populate_sysfs_cells(nvmem);
+ if (rval)
+ goto err_destroy_layout;
+#endif
+
blocking_notifier_call_chain(&nvmem_notifier, NVMEM_ADD, nvmem);

return nvmem;

+#ifdef CONFIG_NVMEM_SYSFS
+err_destroy_layout:
+ nvmem_destroy_layout(nvmem);
+#endif
err_remove_dev:
device_del(&nvmem->dev);
err_remove_cells:
diff --git a/drivers/nvmem/internals.h b/drivers/nvmem/internals.h
index 4946456c76c7..18fed57270e5 100644
--- a/drivers/nvmem/internals.h
+++ b/drivers/nvmem/internals.h
@@ -32,6 +32,7 @@ struct nvmem_device {
struct gpio_desc *wp_gpio;
struct nvmem_layout *layout;
void *priv;
+ bool sysfs_cells_populated;
};

#if IS_ENABLED(CONFIG_OF)
--
2.25.1


2023-12-15 11:17:49

by Srinivas Kandagatla

[permalink] [raw]
Subject: [PATCH 06/10] nvmem: core: Rework layouts to become regular devices

From: Miquel Raynal <[email protected]>

Current layout support was initially written without modules support in
mind. When the requirement for module support rose, the existing base
was improved to adopt modularization support, but kind of a design flaw
was introduced. With the existing implementation, when a storage device
registers into NVMEM, the core tries to hook a layout (if any) and
populates its cells immediately. This means, if the hardware description
expects a layout to be hooked up, but no driver was provided for that,
the storage medium will fail to probe and try later from
scratch. Even if we consider that the hardware description shall be
correct, we could still probe the storage device (especially if it
contains the rootfs).

One way to overcome this situation is to consider the layouts as
devices, and leverage the native notifier mechanism. When a new NVMEM
device is registered, we can populate its nvmem-layout child, if any,
and wait for the matching to be done in order to get the cells (the
waiting can be easily done with the NVMEM notifiers). If the layout
driver is compiled as a module, it should automatically be loaded. This
way, there is no strong order to enforce, any NVMEM device creation
or NVMEM layout driver insertion will be observed as a new event which
may lead to the creation of additional cells, without disturbing the
probes with costly (and sometimes endless) deferrals.

In order to achieve that goal we create a new bus for the nvmem-layouts
with minimal logic to match nvmem-layout devices with nvmem-layout
drivers. All this infrastructure code is created in the layouts.c file.

Signed-off-by: Miquel Raynal <[email protected]>
Tested-by: Rafał Miłecki <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
---
drivers/nvmem/Kconfig | 1 +
drivers/nvmem/Makefile | 2 +
drivers/nvmem/core.c | 170 ++++++++++----------------
drivers/nvmem/internals.h | 21 ++++
drivers/nvmem/layouts.c | 201 +++++++++++++++++++++++++++++++
drivers/nvmem/layouts/Kconfig | 8 ++
drivers/nvmem/layouts/onie-tlv.c | 24 +++-
drivers/nvmem/layouts/sl28vpd.c | 24 +++-
include/linux/nvmem-provider.h | 38 +++---
9 files changed, 354 insertions(+), 135 deletions(-)
create mode 100644 drivers/nvmem/layouts.c

diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
index 5bc9c4874fe3..283134498fbc 100644
--- a/drivers/nvmem/Kconfig
+++ b/drivers/nvmem/Kconfig
@@ -1,6 +1,7 @@
# SPDX-License-Identifier: GPL-2.0-only
menuconfig NVMEM
bool "NVMEM Support"
+ imply NVMEM_LAYOUTS
help
Support for NVMEM(Non Volatile Memory) devices like EEPROM, EFUSES...

diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile
index 423baf089515..cdd01fbf1313 100644
--- a/drivers/nvmem/Makefile
+++ b/drivers/nvmem/Makefile
@@ -5,6 +5,8 @@

obj-$(CONFIG_NVMEM) += nvmem_core.o
nvmem_core-y := core.o
+obj-$(CONFIG_NVMEM_LAYOUTS) += nvmem_layouts.o
+nvmem_layouts-y := layouts.o
obj-y += layouts/

# Devices
diff --git a/drivers/nvmem/core.c b/drivers/nvmem/core.c
index a885713d6b4b..4c2154ddf8a7 100644
--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -55,9 +55,6 @@ 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)
{
@@ -740,97 +737,22 @@ static int nvmem_add_cells_from_fixed_layout(struct nvmem_device *nvmem)
return err;
}

-int __nvmem_layout_register(struct nvmem_layout *layout, struct module *owner)
+int nvmem_layout_register(struct nvmem_layout *layout)
{
- layout->owner = owner;
-
- spin_lock(&nvmem_layout_lock);
- list_add(&layout->node, &nvmem_layouts);
- spin_unlock(&nvmem_layout_lock);
-
- blocking_notifier_call_chain(&nvmem_notifier, NVMEM_LAYOUT_ADD, layout);
+ if (!layout->add_cells)
+ return -EINVAL;

- return 0;
+ /* Populate the cells */
+ return layout->add_cells(&layout->nvmem->dev, layout->nvmem);
}
-EXPORT_SYMBOL_GPL(__nvmem_layout_register);
+EXPORT_SYMBOL_GPL(nvmem_layout_register);

void nvmem_layout_unregister(struct nvmem_layout *layout)
{
- blocking_notifier_call_chain(&nvmem_notifier, NVMEM_LAYOUT_REMOVE, layout);
-
- spin_lock(&nvmem_layout_lock);
- list_del(&layout->node);
- spin_unlock(&nvmem_layout_lock);
+ /* Keep the API even with an empty stub in case we need it later */
}
EXPORT_SYMBOL_GPL(nvmem_layout_unregister);

-static struct nvmem_layout *nvmem_layout_get(struct nvmem_device *nvmem)
-{
- struct device_node *layout_np;
- struct nvmem_layout *l, *layout = ERR_PTR(-EPROBE_DEFER);
-
- layout_np = of_nvmem_layout_get_container(nvmem);
- if (!layout_np)
- return NULL;
-
- /* Fixed layouts don't have a matching driver */
- if (of_device_is_compatible(layout_np, "fixed-layout")) {
- of_node_put(layout_np);
- return NULL;
- }
-
- /*
- * In case the nvmem device was built-in while the layout was built as a
- * module, we shall manually request the layout driver loading otherwise
- * we'll never have any match.
- */
- of_request_module(layout_np);
-
- 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);
- if (ret)
- return ret;
- }
-
- return 0;
-}
-
-#if IS_ENABLED(CONFIG_OF)
-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)
{
@@ -838,7 +760,7 @@ const void *nvmem_layout_get_match_data(struct nvmem_device *nvmem,
const struct of_device_id *match;

layout_np = of_nvmem_layout_get_container(nvmem);
- match = of_match_node(layout->of_match_table, layout_np);
+ match = of_match_node(layout->dev.driver->of_match_table, layout_np);

return match ? match->data : NULL;
}
@@ -950,19 +872,6 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config)
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 (IS_ERR(nvmem->layout)) {
- rval = PTR_ERR(nvmem->layout);
- nvmem->layout = NULL;
-
- if (rval == -EPROBE_DEFER)
- goto err_teardown_compat;
- }
-
if (config->cells) {
rval = nvmem_add_cells(nvmem, config->cells, config->ncells);
if (rval)
@@ -983,24 +892,24 @@ struct nvmem_device *nvmem_register(const struct nvmem_config *config)
if (rval)
goto err_remove_cells;

- rval = nvmem_add_cells_from_layout(nvmem);
- if (rval)
- goto err_remove_cells;
-
dev_dbg(&nvmem->dev, "Registering nvmem device %s\n", config->name);

rval = device_add(&nvmem->dev);
if (rval)
goto err_remove_cells;

+ rval = nvmem_populate_layout(nvmem);
+ if (rval)
+ goto err_remove_dev;
+
blocking_notifier_call_chain(&nvmem_notifier, NVMEM_ADD, nvmem);

return nvmem;

+err_remove_dev:
+ device_del(&nvmem->dev);
err_remove_cells:
nvmem_device_remove_all_cells(nvmem);
- nvmem_layout_put(nvmem->layout);
-err_teardown_compat:
if (config->compat)
nvmem_sysfs_remove_compat(nvmem, config);
err_put_device:
@@ -1022,7 +931,7 @@ static void nvmem_device_release(struct kref *kref)
device_remove_bin_file(nvmem->base_dev, &nvmem->eeprom);

nvmem_device_remove_all_cells(nvmem);
- nvmem_layout_put(nvmem->layout);
+ nvmem_destroy_layout(nvmem);
device_unregister(&nvmem->dev);
}

@@ -1324,6 +1233,12 @@ nvmem_cell_get_from_lookup(struct device *dev, const char *con_id)
return cell;
}

+static void nvmem_layout_module_put(struct nvmem_device *nvmem)
+{
+ if (nvmem->layout && nvmem->layout->dev.driver)
+ module_put(nvmem->layout->dev.driver->owner);
+}
+
#if IS_ENABLED(CONFIG_OF)
static struct nvmem_cell_entry *
nvmem_find_cell_entry_by_node(struct nvmem_device *nvmem, struct device_node *np)
@@ -1342,6 +1257,18 @@ nvmem_find_cell_entry_by_node(struct nvmem_device *nvmem, struct device_node *np
return cell;
}

+static int nvmem_layout_module_get_optional(struct nvmem_device *nvmem)
+{
+ if (!nvmem->layout)
+ return 0;
+
+ if (!nvmem->layout->dev.driver ||
+ !try_module_get(nvmem->layout->dev.driver->owner))
+ return -EPROBE_DEFER;
+
+ return 0;
+}
+
/**
* of_nvmem_cell_get() - Get a nvmem cell from given device node and cell id
*
@@ -1404,16 +1331,29 @@ struct nvmem_cell *of_nvmem_cell_get(struct device_node *np, const char *id)
return ERR_CAST(nvmem);
}

+ ret = nvmem_layout_module_get_optional(nvmem);
+ if (ret) {
+ of_node_put(cell_np);
+ __nvmem_device_put(nvmem);
+ return ERR_PTR(ret);
+ }
+
cell_entry = nvmem_find_cell_entry_by_node(nvmem, cell_np);
of_node_put(cell_np);
if (!cell_entry) {
__nvmem_device_put(nvmem);
- return ERR_PTR(-ENOENT);
+ nvmem_layout_module_put(nvmem);
+ if (nvmem->layout)
+ return ERR_PTR(-EPROBE_DEFER);
+ else
+ return ERR_PTR(-ENOENT);
}

cell = nvmem_create_cell(cell_entry, id, cell_index);
- if (IS_ERR(cell))
+ if (IS_ERR(cell)) {
__nvmem_device_put(nvmem);
+ nvmem_layout_module_put(nvmem);
+ }

return cell;
}
@@ -1527,6 +1467,7 @@ void nvmem_cell_put(struct nvmem_cell *cell)

kfree(cell);
__nvmem_device_put(nvmem);
+ nvmem_layout_module_put(nvmem);
}
EXPORT_SYMBOL_GPL(nvmem_cell_put);

@@ -2104,11 +2045,22 @@ EXPORT_SYMBOL_GPL(nvmem_dev_name);

static int __init nvmem_init(void)
{
- return bus_register(&nvmem_bus_type);
+ int ret;
+
+ ret = bus_register(&nvmem_bus_type);
+ if (ret)
+ return ret;
+
+ ret = nvmem_layout_bus_register();
+ if (ret)
+ bus_unregister(&nvmem_bus_type);
+
+ return ret;
}

static void __exit nvmem_exit(void)
{
+ nvmem_layout_bus_unregister();
bus_unregister(&nvmem_bus_type);
}

diff --git a/drivers/nvmem/internals.h b/drivers/nvmem/internals.h
index 893553fbdf51..4946456c76c7 100644
--- a/drivers/nvmem/internals.h
+++ b/drivers/nvmem/internals.h
@@ -34,4 +34,25 @@ struct nvmem_device {
void *priv;
};

+#if IS_ENABLED(CONFIG_OF)
+int nvmem_layout_bus_register(void);
+void nvmem_layout_bus_unregister(void);
+int nvmem_populate_layout(struct nvmem_device *nvmem);
+void nvmem_destroy_layout(struct nvmem_device *nvmem);
+#else /* CONFIG_OF */
+static inline int nvmem_layout_bus_register(void)
+{
+ return 0;
+}
+
+static inline void nvmem_layout_bus_unregister(void) {}
+
+static inline int nvmem_populate_layout(struct nvmem_device *nvmem)
+{
+ return 0;
+}
+
+static inline void nvmem_destroy_layout(struct nvmem_device *nvmem) { }
+#endif /* CONFIG_OF */
+
#endif /* ifndef _LINUX_NVMEM_INTERNALS_H */
diff --git a/drivers/nvmem/layouts.c b/drivers/nvmem/layouts.c
new file mode 100644
index 000000000000..6a6aa58369ff
--- /dev/null
+++ b/drivers/nvmem/layouts.c
@@ -0,0 +1,201 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * NVMEM layout bus handling
+ *
+ * Copyright (C) 2023 Bootlin
+ * Author: Miquel Raynal <[email protected]
+ */
+
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/nvmem-provider.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+
+#include "internals.h"
+
+#define to_nvmem_layout_driver(drv) \
+ (container_of((drv), struct nvmem_layout_driver, driver))
+#define to_nvmem_layout_device(_dev) \
+ container_of((_dev), struct nvmem_layout, dev)
+
+static int nvmem_layout_bus_match(struct device *dev, struct device_driver *drv)
+{
+ return of_driver_match_device(dev, drv);
+}
+
+static int nvmem_layout_bus_probe(struct device *dev)
+{
+ struct nvmem_layout_driver *drv = to_nvmem_layout_driver(dev->driver);
+ struct nvmem_layout *layout = to_nvmem_layout_device(dev);
+
+ if (!drv->probe || !drv->remove)
+ return -EINVAL;
+
+ return drv->probe(layout);
+}
+
+static void nvmem_layout_bus_remove(struct device *dev)
+{
+ struct nvmem_layout_driver *drv = to_nvmem_layout_driver(dev->driver);
+ struct nvmem_layout *layout = to_nvmem_layout_device(dev);
+
+ return drv->remove(layout);
+}
+
+static struct bus_type nvmem_layout_bus_type = {
+ .name = "nvmem-layout",
+ .match = nvmem_layout_bus_match,
+ .probe = nvmem_layout_bus_probe,
+ .remove = nvmem_layout_bus_remove,
+};
+
+int nvmem_layout_driver_register(struct nvmem_layout_driver *drv)
+{
+ drv->driver.bus = &nvmem_layout_bus_type;
+
+ return driver_register(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(nvmem_layout_driver_register);
+
+void nvmem_layout_driver_unregister(struct nvmem_layout_driver *drv)
+{
+ driver_unregister(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(nvmem_layout_driver_unregister);
+
+static void nvmem_layout_release_device(struct device *dev)
+{
+ struct nvmem_layout *layout = to_nvmem_layout_device(dev);
+
+ of_node_put(layout->dev.of_node);
+ kfree(layout);
+}
+
+static int nvmem_layout_create_device(struct nvmem_device *nvmem,
+ struct device_node *np)
+{
+ struct nvmem_layout *layout;
+ struct device *dev;
+ int ret;
+
+ layout = kzalloc(sizeof(*layout), GFP_KERNEL);
+ if (!layout)
+ return -ENOMEM;
+
+ /* Create a bidirectional link */
+ layout->nvmem = nvmem;
+ nvmem->layout = layout;
+
+ /* Device model registration */
+ dev = &layout->dev;
+ device_initialize(dev);
+ dev->parent = &nvmem->dev;
+ dev->bus = &nvmem_layout_bus_type;
+ dev->release = nvmem_layout_release_device;
+ dev->coherent_dma_mask = DMA_BIT_MASK(32);
+ dev->dma_mask = &dev->coherent_dma_mask;
+ device_set_node(dev, of_fwnode_handle(of_node_get(np)));
+ of_device_make_bus_id(dev);
+ of_msi_configure(dev, dev->of_node);
+
+ ret = device_add(dev);
+ if (ret) {
+ put_device(dev);
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id of_nvmem_layout_skip_table[] = {
+ { .compatible = "fixed-layout", },
+ {}
+};
+
+static int nvmem_layout_bus_populate(struct nvmem_device *nvmem,
+ struct device_node *layout_dn)
+{
+ int ret;
+
+ /* Make sure it has a compatible property */
+ if (!of_get_property(layout_dn, "compatible", NULL)) {
+ pr_debug("%s() - skipping %pOF, no compatible prop\n",
+ __func__, layout_dn);
+ return 0;
+ }
+
+ /* Fixed layouts are parsed manually somewhere else for now */
+ if (of_match_node(of_nvmem_layout_skip_table, layout_dn)) {
+ pr_debug("%s() - skipping %pOF node\n", __func__, layout_dn);
+ return 0;
+ }
+
+ if (of_node_check_flag(layout_dn, OF_POPULATED_BUS)) {
+ pr_debug("%s() - skipping %pOF, already populated\n",
+ __func__, layout_dn);
+
+ return 0;
+ }
+
+ /* NVMEM layout buses expect only a single device representing the layout */
+ ret = nvmem_layout_create_device(nvmem, layout_dn);
+ if (ret)
+ return ret;
+
+ of_node_set_flag(layout_dn, OF_POPULATED_BUS);
+
+ return 0;
+}
+
+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);
+
+/*
+ * Returns the number of devices populated, 0 if the operation was not relevant
+ * for this nvmem device, an error code otherwise.
+ */
+int nvmem_populate_layout(struct nvmem_device *nvmem)
+{
+ struct device_node *layout_dn;
+ int ret;
+
+ layout_dn = of_nvmem_layout_get_container(nvmem);
+ if (!layout_dn)
+ return 0;
+
+ /* Populate the layout device */
+ device_links_supplier_sync_state_pause();
+ ret = nvmem_layout_bus_populate(nvmem, layout_dn);
+ device_links_supplier_sync_state_resume();
+
+ of_node_put(layout_dn);
+ return ret;
+}
+
+void nvmem_destroy_layout(struct nvmem_device *nvmem)
+{
+ struct device *dev;
+
+ if (!nvmem->layout)
+ return;
+
+ dev = &nvmem->layout->dev;
+ of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
+ device_unregister(dev);
+}
+
+int nvmem_layout_bus_register(void)
+{
+ return bus_register(&nvmem_layout_bus_type);
+}
+
+void nvmem_layout_bus_unregister(void)
+{
+ bus_unregister(&nvmem_layout_bus_type);
+}
diff --git a/drivers/nvmem/layouts/Kconfig b/drivers/nvmem/layouts/Kconfig
index 7ff1ee1c1f05..9c6e672fc350 100644
--- a/drivers/nvmem/layouts/Kconfig
+++ b/drivers/nvmem/layouts/Kconfig
@@ -1,5 +1,11 @@
# SPDX-License-Identifier: GPL-2.0

+config NVMEM_LAYOUTS
+ bool
+ depends on OF
+
+if NVMEM_LAYOUTS
+
menu "Layout Types"

config NVMEM_LAYOUT_SL28_VPD
@@ -21,3 +27,5 @@ config NVMEM_LAYOUT_ONIE_TLV
If unsure, say N.

endmenu
+
+endif
diff --git a/drivers/nvmem/layouts/onie-tlv.c b/drivers/nvmem/layouts/onie-tlv.c
index defd42d4375c..b24cc5dcc6ee 100644
--- a/drivers/nvmem/layouts/onie-tlv.c
+++ b/drivers/nvmem/layouts/onie-tlv.c
@@ -225,16 +225,32 @@ static int onie_tlv_parse_table(struct device *dev, struct nvmem_device *nvmem)
return 0;
}

+static int onie_tlv_probe(struct nvmem_layout *layout)
+{
+ layout->add_cells = onie_tlv_parse_table;
+
+ return nvmem_layout_register(layout);
+}
+
+static void onie_tlv_remove(struct nvmem_layout *layout)
+{
+ nvmem_layout_unregister(layout);
+}
+
static const struct of_device_id onie_tlv_of_match_table[] = {
{ .compatible = "onie,tlv-layout", },
{},
};
MODULE_DEVICE_TABLE(of, onie_tlv_of_match_table);

-static struct nvmem_layout onie_tlv_layout = {
- .name = "ONIE tlv layout",
- .of_match_table = onie_tlv_of_match_table,
- .add_cells = onie_tlv_parse_table,
+static struct nvmem_layout_driver onie_tlv_layout = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "onie-tlv-layout",
+ .of_match_table = onie_tlv_of_match_table,
+ },
+ .probe = onie_tlv_probe,
+ .remove = onie_tlv_remove,
};
module_nvmem_layout_driver(onie_tlv_layout);

diff --git a/drivers/nvmem/layouts/sl28vpd.c b/drivers/nvmem/layouts/sl28vpd.c
index 26c7cf21b523..b8ffae646cc2 100644
--- a/drivers/nvmem/layouts/sl28vpd.c
+++ b/drivers/nvmem/layouts/sl28vpd.c
@@ -134,16 +134,32 @@ static int sl28vpd_add_cells(struct device *dev, struct nvmem_device *nvmem)
return 0;
}

+static int sl28vpd_probe(struct nvmem_layout *layout)
+{
+ layout->add_cells = sl28vpd_add_cells;
+
+ return nvmem_layout_register(layout);
+}
+
+static void sl28vpd_remove(struct nvmem_layout *layout)
+{
+ nvmem_layout_unregister(layout);
+}
+
static const struct of_device_id sl28vpd_of_match_table[] = {
{ .compatible = "kontron,sl28-vpd" },
{},
};
MODULE_DEVICE_TABLE(of, sl28vpd_of_match_table);

-static struct nvmem_layout sl28vpd_layout = {
- .name = "sl28-vpd",
- .of_match_table = sl28vpd_of_match_table,
- .add_cells = sl28vpd_add_cells,
+static struct nvmem_layout_driver sl28vpd_layout = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "kontron-sl28vpd-layout",
+ .of_match_table = sl28vpd_of_match_table,
+ },
+ .probe = sl28vpd_probe,
+ .remove = sl28vpd_remove,
};
module_nvmem_layout_driver(sl28vpd_layout);

diff --git a/include/linux/nvmem-provider.h b/include/linux/nvmem-provider.h
index 36415a602d9e..6fe65b35ea97 100644
--- a/include/linux/nvmem-provider.h
+++ b/include/linux/nvmem-provider.h
@@ -9,6 +9,7 @@
#ifndef _LINUX_NVMEM_PROVIDER_H
#define _LINUX_NVMEM_PROVIDER_H

+#include <linux/device.h>
#include <linux/device/driver.h>
#include <linux/err.h>
#include <linux/errno.h>
@@ -158,12 +159,11 @@ struct nvmem_cell_table {
/**
* struct nvmem_layout - NVMEM layout definitions
*
- * @name: Layout name.
- * @of_match_table: Open firmware match table.
- * @add_cells: Called to populate the layout using
- * nvmem_add_one_cell().
- * @owner: Pointer to struct module.
- * @node: List node.
+ * @dev: Device-model layout device.
+ * @nvmem: The underlying NVMEM device
+ * @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().
*
* 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"
@@ -171,13 +171,15 @@ struct nvmem_cell_table {
* cells.
*/
struct nvmem_layout {
- const char *name;
- const struct of_device_id *of_match_table;
+ struct device dev;
+ struct nvmem_device *nvmem;
int (*add_cells)(struct device *dev, struct nvmem_device *nvmem);
+};

- /* private */
- struct module *owner;
- struct list_head node;
+struct nvmem_layout_driver {
+ struct device_driver driver;
+ int (*probe)(struct nvmem_layout *layout);
+ void (*remove)(struct nvmem_layout *layout);
};

#if IS_ENABLED(CONFIG_NVMEM)
@@ -194,11 +196,15 @@ void nvmem_del_cell_table(struct nvmem_cell_table *table);
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)
+int nvmem_layout_register(struct nvmem_layout *layout);
void nvmem_layout_unregister(struct nvmem_layout *layout);

+int nvmem_layout_driver_register(struct nvmem_layout_driver *drv);
+void nvmem_layout_driver_unregister(struct nvmem_layout_driver *drv);
+#define module_nvmem_layout_driver(__nvmem_layout_driver) \
+ module_driver(__nvmem_layout_driver, nvmem_layout_driver_register, \
+ nvmem_layout_driver_unregister)
+
const void *nvmem_layout_get_match_data(struct nvmem_device *nvmem,
struct nvmem_layout *layout);

@@ -262,8 +268,4 @@ static inline struct device_node *of_nvmem_layout_get_container(struct nvmem_dev

#endif /* CONFIG_NVMEM && CONFIG_OF */

-#define module_nvmem_layout_driver(__layout_driver) \
- module_driver(__layout_driver, nvmem_layout_register, \
- nvmem_layout_unregister)
-
#endif /* ifndef _LINUX_NVMEM_PROVIDER_H */
--
2.25.1


2023-12-15 11:17:58

by Srinivas Kandagatla

[permalink] [raw]
Subject: [PATCH 09/10] dt-bindings: nvmem: add new stm32mp25 compatible for stm32-romem

From: Patrick Delaunay <[email protected]>

Add a new compatible for stm32mp25 support.

Signed-off-by: Patrick Delaunay <[email protected]>
Acked-by: Conor Dooley <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
---
Documentation/devicetree/bindings/nvmem/st,stm32-romem.yaml | 1 +
1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/nvmem/st,stm32-romem.yaml b/Documentation/devicetree/bindings/nvmem/st,stm32-romem.yaml
index a69de3e92282..92bfe25f0571 100644
--- a/Documentation/devicetree/bindings/nvmem/st,stm32-romem.yaml
+++ b/Documentation/devicetree/bindings/nvmem/st,stm32-romem.yaml
@@ -24,6 +24,7 @@ properties:
- st,stm32f4-otp
- st,stm32mp13-bsec
- st,stm32mp15-bsec
+ - st,stm32mp25-bsec

reg:
maxItems: 1
--
2.25.1


2023-12-15 11:17:58

by Srinivas Kandagatla

[permalink] [raw]
Subject: [PATCH 07/10] ABI: sysfs-nvmem-cells: Expose cells through sysfs

From: Miquel Raynal <[email protected]>

The binary content of nvmem devices is available to the user so in the
easiest cases, finding the content of a cell is rather easy as it is
just a matter of looking at a known and fixed offset. However, nvmem
layouts have been recently introduced to cope with more advanced
situations, where the offset and size of the cells is not known in
advance or is dynamic. When using layouts, more advanced parsers are
used by the kernel in order to give direct access to the content of each
cell regardless of their position/size in the underlying device, but
these information were not accessible to the user.

By exposing the nvmem cells to the user through a dedicated cell/ folder
containing one file per cell, we provide a straightforward access to
useful user information without the need for re-writing a userland
parser. Content of nvmem cells is usually: product names, manufacturing
date, MAC addresses, etc,

Signed-off-by: Miquel Raynal <[email protected]>
Reviewed-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
---
Documentation/ABI/testing/sysfs-nvmem-cells | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-nvmem-cells

diff --git a/Documentation/ABI/testing/sysfs-nvmem-cells b/Documentation/ABI/testing/sysfs-nvmem-cells
new file mode 100644
index 000000000000..7af70adf3690
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-nvmem-cells
@@ -0,0 +1,21 @@
+What: /sys/bus/nvmem/devices/.../cells/<cell-name>
+Date: May 2023
+KernelVersion: 6.5
+Contact: Miquel Raynal <[email protected]>
+Description:
+ The "cells" folder contains one file per cell exposed by the
+ NVMEM device. The name of the file is: <name>@<where>, with
+ <name> being the cell name and <where> its location in the NVMEM
+ device, in hexadecimal (without the '0x' prefix, to mimic device
+ tree node names). The length of the file is the size of the cell
+ (when known). The content of the file is the binary content of
+ the cell (may sometimes be ASCII, likely without trailing
+ character).
+ Note: This file is only present if CONFIG_NVMEM_SYSFS
+ is enabled.
+
+ Example::
+
+ hexdump -C /sys/bus/nvmem/devices/1-00563/cells/product-name@d
+ 00000000 54 4e 34 38 4d 2d 50 2d 44 4e |TN48M-P-DN|
+ 0000000a
--
2.25.1


2023-12-15 11:18:10

by Srinivas Kandagatla

[permalink] [raw]
Subject: [PATCH 10/10] nvmem: stm32: add support for STM32MP25 BSEC to control OTP data

From: Patrick Delaunay <[email protected]>

On STM32MP25, OTP area may be read/written by using BSEC (boot, security
and OTP control). The BSEC internal peripheral is only managed by the
secure world.

The 12 Kbits of OTP (effective) are organized into the following regions:
- lower OTP (OTP0 to OTP127) = 4096 lower OTP bits,
bitwise (1-bit) programmable
- mid OTP (OTP128 to OTP255) = 4096 middle OTP bits,
bulk (32-bit) programmable
- upper OTP (OTP256 to OTP383) = 4096 upper OTP bits,
bulk (32-bit) programmable,
only accessible when BSEC is in closed state.

As HWKEY and ECIES key are only accessible by ROM code;
only 368 OTP words are managed in this driver (OTP0 to OTP267).

This patch adds the STM32MP25 configuration for reading and writing
the OTP data using the OP-TEE BSEC TA services.

Signed-off-by: Patrick Delaunay <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
---
drivers/nvmem/stm32-romem.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)

diff --git a/drivers/nvmem/stm32-romem.c b/drivers/nvmem/stm32-romem.c
index 8a553b1799a8..82879b1c9eb9 100644
--- a/drivers/nvmem/stm32-romem.c
+++ b/drivers/nvmem/stm32-romem.c
@@ -269,6 +269,19 @@ static const struct stm32_romem_cfg stm32mp13_bsec_cfg = {
.ta = true,
};

+/*
+ * STM32MP25 BSEC OTP: 3 regions of 32-bits data words
+ * lower OTP (OTP0 to OTP127), bitwise (1-bit) programmable
+ * mid OTP (OTP128 to OTP255), bulk (32-bit) programmable
+ * upper OTP (OTP256 to OTP383), bulk (32-bit) programmable
+ * but no access to HWKEY and ECIES key: limited at OTP367
+ */
+static const struct stm32_romem_cfg stm32mp25_bsec_cfg = {
+ .size = 368 * 4,
+ .lower = 127,
+ .ta = true,
+};
+
static const struct of_device_id stm32_romem_of_match[] __maybe_unused = {
{ .compatible = "st,stm32f4-otp", }, {
.compatible = "st,stm32mp15-bsec",
@@ -276,6 +289,9 @@ static const struct of_device_id stm32_romem_of_match[] __maybe_unused = {
}, {
.compatible = "st,stm32mp13-bsec",
.data = (void *)&stm32mp13_bsec_cfg,
+ }, {
+ .compatible = "st,stm32mp25-bsec",
+ .data = (void *)&stm32mp25_bsec_cfg,
},
{ /* sentinel */ },
};
--
2.25.1