[PATCH v4 1/2] dt-bindings: nvmem: Add t1023-sfp efuse support

[PATCH v4 1/2] dt-bindings: nvmem: Add t1023-sfp efuse support

[Richard Alpe]

Add a schema for the NVMEM eFuse (SFP) layout on the NXP QorIQ SOC.

Signed-off-by: Richard Alpe <richard@bit42.se>
---
v3: Updates according to feedback from Krzysztof.

 .../bindings/nvmem/fsl,t1023-sfp.yaml         | 37 +++++++++++++++++++
 1 file changed, 37 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/nvmem/fsl,t1023-sfp.yaml

diff --git a/Documentation/devicetree/bindings/nvmem/fsl,t1023-sfp.yaml b/Documentation/devicetree/bindings/nvmem/fsl,t1023-sfp.yaml
new file mode 100644
index 000000000000..a9d249d4dbba
--- /dev/null
+++ b/Documentation/devicetree/bindings/nvmem/fsl,t1023-sfp.yaml
@@ -0,0 +1,37 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/nvmem/fsl,t1023.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NXP QorIQ eFuse support
+
+maintainers:
+  - Richard Alpe <richard@bit42.se>
+
+description:
+  Read support for the eFuses (SFP) on NXP QorIQ series SoC's.
+
+allOf:
+  - $ref: nvmem.yaml#
+
+properties:
+  compatible:
+    const: fsl,t1023-sfp
+
+  reg:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    efuse@e8000 {
+        compatible = "fsl,t1023-sfp";
+        reg = <0xe8000 0x1000>;
+    };
+...
-- 
2.34.1

[PATCH v4 2/2] nvmem: add new NXP QorIQ eFuse driver

[Richard Alpe]

Add SFP (Security Fuse Processor) read support for NXP (Freescale)
QorIQ series SOC's.

This patch adds support for the T1023 SOC using the SFP offset from
the existing T1023 device tree. In theory this should also work for
T1024, T1014 and T1013 which uses the same SFP base offset.

Signed-off-by: Richard Alpe <richard@bit42.se>
---
v2: Updates according to feedback from Srinivas.
v3: No changes to this patch.

 drivers/nvmem/Kconfig       | 12 ++++++
 drivers/nvmem/Makefile      |  2 +
 drivers/nvmem/qoriq-efuse.c | 78 +++++++++++++++++++++++++++++++++++++
 3 files changed, 92 insertions(+)
 create mode 100644 drivers/nvmem/qoriq-efuse.c

diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
index 6dec38805041..43446e5f7d9b 100644
--- a/drivers/nvmem/Kconfig
+++ b/drivers/nvmem/Kconfig
@@ -377,4 +377,16 @@ config NVMEM_ZYNQMP
 
 	  If sure, say yes. If unsure, say no.
 
+config NVMEM_QORIQ_EFUSE
+	tristate "NXP QorIQ eFuse support"
+	depends on PPC_85xx || COMPILE_TEST
+	depends on HAS_IOMEM
+	help
+	  This driver provides read support for the eFuses (SFP) on NXP QorIQ
+	  series SoC's. This includes secure boot settings, the globally unique
+	  NXP ID 'FUIDR' and the OEM unique ID 'OUIDR'.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called nvmem_qoriq_efuse.
+
 endif
diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile
index 6a1efffa88f0..b8fdf9b51953 100644
--- a/drivers/nvmem/Makefile
+++ b/drivers/nvmem/Makefile
@@ -74,3 +74,5 @@ obj-$(CONFIG_NVMEM_VF610_OCOTP)		+= nvmem-vf610-ocotp.o
 nvmem-vf610-ocotp-y			:= vf610-ocotp.o
 obj-$(CONFIG_NVMEM_ZYNQMP)		+= nvmem_zynqmp_nvmem.o
 nvmem_zynqmp_nvmem-y			:= zynqmp_nvmem.o
+obj-$(CONFIG_NVMEM_QORIQ_EFUSE)		+= nvmem-qoriq-efuse.o
+nvmem-qoriq-efuse-y			:= qoriq-efuse.o
diff --git a/drivers/nvmem/qoriq-efuse.c b/drivers/nvmem/qoriq-efuse.c
new file mode 100644
index 000000000000..e7fd04d6dd94
--- /dev/null
+++ b/drivers/nvmem/qoriq-efuse.c
@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  Copyright (C) 2023  Westermo Network Technologies AB
+ */
+
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/nvmem-provider.h>
+#include <linux/platform_device.h>
+
+struct qoriq_efuse_priv {
+	void __iomem *base;
+};
+
+static int qoriq_efuse_read(void *context, unsigned int offset, void *val,
+			    size_t bytes)
+{
+	struct qoriq_efuse_priv *priv = context;
+
+	/* .stride = 4 so offset is guaranteed to be aligned */
+	__ioread32_copy(val, priv->base + offset, bytes / 4);
+
+	/* Ignore trailing bytes (there shouldn't be any) */
+
+	return 0;
+}
+
+static int qoriq_efuse_probe(struct platform_device *pdev)
+{
+	struct nvmem_config config = {
+		.dev = &pdev->dev,
+		.read_only = true,
+		.reg_read = qoriq_efuse_read,
+		.stride = sizeof(u32),
+		.word_size = sizeof(u32),
+		.name = "qoriq_efuse_read",
+		.id = NVMEM_DEVID_AUTO,
+		.root_only = true,
+	};
+	struct qoriq_efuse_priv *priv;
+	struct nvmem_device *nvmem;
+	struct resource *res;
+
+	priv = devm_kzalloc(config.dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
+	if (IS_ERR(priv->base))
+		return PTR_ERR(priv->base);
+
+	config.size = resource_size(res);
+	config.priv = priv;
+	nvmem = devm_nvmem_register(config.dev, &config);
+
+	return PTR_ERR_OR_ZERO(nvmem);
+}
+
+static const struct of_device_id qoriq_efuse_of_match[] = {
+	{ .compatible = "fsl,t1023-sfp", },
+	{/* sentinel */},
+};
+MODULE_DEVICE_TABLE(of, qoriq_efuse_of_match);
+
+static struct platform_driver qoriq_efuse_driver = {
+	.probe = qoriq_efuse_probe,
+	.driver = {
+		.name = "qoriq-efuse",
+		.of_match_table = qoriq_efuse_of_match,
+	},
+};
+module_platform_driver(qoriq_efuse_driver);
+
+MODULE_AUTHOR("Richard Alpe <richard.alpe@bit42.se>");
+MODULE_DESCRIPTION("NXP QorIQ Security Fuse Processor (SFP) Reader");
+MODULE_LICENSE("GPL");
-- 
2.34.1

Re: [PATCH v4 1/2] dt-bindings: nvmem: Add t1023-sfp efuse support

[Rob Herring]

On Mon, 03 Apr 2023 16:41:05 +0200, Richard Alpe wrote:
> Add a schema for the NVMEM eFuse (SFP) layout on the NXP QorIQ SOC.
> 
> Signed-off-by: Richard Alpe <richard@bit42.se>
> ---
> v3: Updates according to feedback from Krzysztof.
> 
>  .../bindings/nvmem/fsl,t1023-sfp.yaml         | 37 +++++++++++++++++++
>  1 file changed, 37 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/nvmem/fsl,t1023-sfp.yaml
> 

My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
on your patch (DT_CHECKER_FLAGS is new in v5.13):

yamllint warnings/errors:

dtschema/dtc warnings/errors:
./Documentation/devicetree/bindings/nvmem/fsl,t1023-sfp.yaml: $id: relative path/filename doesn't match actual path or filename
	expected: http://devicetree.org/schemas/nvmem/fsl,t1023-sfp.yaml#

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20230403144106.2776249-1-richard@bit42.se

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.