Signed-off-by: Sven Peter <[email protected]>
---
v4:
- new commit to split off MAINTAINER changes requested by Srinivas Kandagatla
MAINTAINERS | 2 ++
1 file changed, 2 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index fd768d43e048..1bf57fd937b5 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1837,6 +1837,7 @@ F: Documentation/devicetree/bindings/clock/apple,nco.yaml
F: Documentation/devicetree/bindings/i2c/apple,i2c.yaml
F: Documentation/devicetree/bindings/interrupt-controller/apple,*
F: Documentation/devicetree/bindings/mailbox/apple,mailbox.yaml
+F: Documentation/devicetree/bindings/nvmem/apple,efuses.yaml
F: Documentation/devicetree/bindings/pci/apple,pcie.yaml
F: Documentation/devicetree/bindings/pinctrl/apple,pinctrl.yaml
F: Documentation/devicetree/bindings/power/apple*
@@ -1847,6 +1848,7 @@ F: drivers/i2c/busses/i2c-pasemi-core.c
F: drivers/i2c/busses/i2c-pasemi-platform.c
F: drivers/irqchip/irq-apple-aic.c
F: drivers/mailbox/apple-mailbox.c
+F: drivers/nvmem/apple-efuses.c
F: drivers/pinctrl/pinctrl-apple-gpio.c
F: drivers/soc/apple/*
F: drivers/watchdog/apple_wdt.c
--
2.25.1
Apple SoCs contain eFuses used to store factory-programmed data such
as calibration values for the PCIe or the Type-C PHY. They are organized
as 32bit values exposed as MMIO.
Signed-off-by: Sven Peter <[email protected]>
---
v3 -> v4:
- rebased on 5.18-rc1 and split off MAINTAINER changes as requested
by Srinivas Kandagatla
v2 -> v3:
- removed .owner = THIS_MODULE again since it's already done by the
core as pointed out by Krzysztof Kozlowski
v1 -> v2:
- fixed sparse warning about __iomem by introducing
struct apple_efuses_priv as done in other nvmem drivers
- make sure the driver actually works as a module by
setting .owner to THIS_MODULE and adding MODULE_DEVICE_TABLE
pointed out by Joey Gouly
drivers/nvmem/Kconfig | 12 ++++++
drivers/nvmem/Makefile | 2 +
drivers/nvmem/apple-efuses.c | 80 ++++++++++++++++++++++++++++++++++++
3 files changed, 94 insertions(+)
create mode 100644 drivers/nvmem/apple-efuses.c
diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
index 555aa77a574d..6283e09cc1e9 100644
--- a/drivers/nvmem/Kconfig
+++ b/drivers/nvmem/Kconfig
@@ -324,4 +324,16 @@ config NVMEM_SUNPLUS_OCOTP
This driver can also be built as a module. If so, the module
will be called nvmem-sunplus-ocotp.
+config NVMEM_APPLE_EFUSES
+ tristate "Apple eFuse support"
+ depends on ARCH_APPLE || COMPILE_TEST
+ default ARCH_APPLE
+ help
+ Say y here to enable support for reading eFuses on Apple SoCs
+ such as the M1. These are e.g. used to store factory programmed
+ calibration data required for the PCIe or the USB-C PHY.
+
+ This driver can also be built as a module. If so, the module will
+ be called nvmem-apple-efuses.
+
endif
diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile
index 891958e29d25..00e136a0a123 100644
--- a/drivers/nvmem/Makefile
+++ b/drivers/nvmem/Makefile
@@ -65,3 +65,5 @@ obj-$(CONFIG_NVMEM_LAYERSCAPE_SFP) += nvmem-layerscape-sfp.o
nvmem-layerscape-sfp-y := layerscape-sfp.o
obj-$(CONFIG_NVMEM_SUNPLUS_OCOTP) += nvmem_sunplus_ocotp.o
nvmem_sunplus_ocotp-y := sunplus-ocotp.o
+obj-$(CONFIG_NVMEM_APPLE_EFUSES) += nvmem-apple-efuses.o
+nvmem-apple-efuses-y := apple-efuses.o
diff --git a/drivers/nvmem/apple-efuses.c b/drivers/nvmem/apple-efuses.c
new file mode 100644
index 000000000000..9b7c87102104
--- /dev/null
+++ b/drivers/nvmem/apple-efuses.c
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Apple SoC eFuse driver
+ *
+ * Copyright (C) The Asahi Linux Contributors
+ */
+
+#include <linux/io.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/nvmem-provider.h>
+#include <linux/platform_device.h>
+
+struct apple_efuses_priv {
+ void __iomem *fuses;
+};
+
+static int apple_efuses_read(void *context, unsigned int offset, void *val,
+ size_t bytes)
+{
+ struct apple_efuses_priv *priv = context;
+ u32 *dst = val;
+
+ while (bytes >= sizeof(u32)) {
+ *dst++ = readl_relaxed(priv->fuses + offset);
+ bytes -= sizeof(u32);
+ offset += sizeof(u32);
+ }
+
+ return 0;
+}
+
+static int apple_efuses_probe(struct platform_device *pdev)
+{
+ struct apple_efuses_priv *priv;
+ struct resource *res;
+ struct nvmem_config config = {
+ .dev = &pdev->dev,
+ .read_only = true,
+ .reg_read = apple_efuses_read,
+ .stride = sizeof(u32),
+ .word_size = sizeof(u32),
+ .name = "apple_efuses_nvmem",
+ .id = NVMEM_DEVID_AUTO,
+ .root_only = true,
+ };
+
+ priv = devm_kzalloc(config.dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->fuses = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
+ if (IS_ERR(priv->fuses))
+ return PTR_ERR(priv->fuses);
+
+ config.priv = priv;
+ config.size = resource_size(res);
+
+ return PTR_ERR_OR_ZERO(devm_nvmem_register(config.dev, &config));
+}
+
+static const struct of_device_id apple_efuses_of_match[] = {
+ { .compatible = "apple,efuses", },
+ {}
+};
+
+MODULE_DEVICE_TABLE(of, apple_efuses_of_match);
+
+static struct platform_driver apple_efuses_driver = {
+ .driver = {
+ .name = "apple_efuses",
+ .of_match_table = apple_efuses_of_match,
+ },
+ .probe = apple_efuses_probe,
+};
+
+module_platform_driver(apple_efuses_driver);
+
+MODULE_AUTHOR("Sven Peter <[email protected]>");
+MODULE_LICENSE("GPL");
--
2.25.1
On 10/04/2022 14:54, Sven Peter wrote:
> Apple SoCs contain eFuses used to store factory-programmed data such
> as calibration values for the PCIe or the Type-C PHY. They are organized
> as 32bit values exposed as MMIO.
>
> Signed-off-by: Sven Peter <[email protected]>
Applied all 3,
thanks,
--srini
> ---
> v3 -> v4:
> - rebased on 5.18-rc1 and split off MAINTAINER changes as requested
> by Srinivas Kandagatla
> v2 -> v3:
> - removed .owner = THIS_MODULE again since it's already done by the
> core as pointed out by Krzysztof Kozlowski
> v1 -> v2:
> - fixed sparse warning about __iomem by introducing
> struct apple_efuses_priv as done in other nvmem drivers
> - make sure the driver actually works as a module by
> setting .owner to THIS_MODULE and adding MODULE_DEVICE_TABLE
> pointed out by Joey Gouly
>
> drivers/nvmem/Kconfig | 12 ++++++
> drivers/nvmem/Makefile | 2 +
> drivers/nvmem/apple-efuses.c | 80 ++++++++++++++++++++++++++++++++++++
> 3 files changed, 94 insertions(+)
> create mode 100644 drivers/nvmem/apple-efuses.c
>
> diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
> index 555aa77a574d..6283e09cc1e9 100644
> --- a/drivers/nvmem/Kconfig
> +++ b/drivers/nvmem/Kconfig
> @@ -324,4 +324,16 @@ config NVMEM_SUNPLUS_OCOTP
> This driver can also be built as a module. If so, the module
> will be called nvmem-sunplus-ocotp.
>
> +config NVMEM_APPLE_EFUSES
> + tristate "Apple eFuse support"
> + depends on ARCH_APPLE || COMPILE_TEST
> + default ARCH_APPLE
> + help
> + Say y here to enable support for reading eFuses on Apple SoCs
> + such as the M1. These are e.g. used to store factory programmed
> + calibration data required for the PCIe or the USB-C PHY.
> +
> + This driver can also be built as a module. If so, the module will
> + be called nvmem-apple-efuses.
> +
> endif
> diff --git a/drivers/nvmem/Makefile b/drivers/nvmem/Makefile
> index 891958e29d25..00e136a0a123 100644
> --- a/drivers/nvmem/Makefile
> +++ b/drivers/nvmem/Makefile
> @@ -65,3 +65,5 @@ obj-$(CONFIG_NVMEM_LAYERSCAPE_SFP) += nvmem-layerscape-sfp.o
> nvmem-layerscape-sfp-y := layerscape-sfp.o
> obj-$(CONFIG_NVMEM_SUNPLUS_OCOTP) += nvmem_sunplus_ocotp.o
> nvmem_sunplus_ocotp-y := sunplus-ocotp.o
> +obj-$(CONFIG_NVMEM_APPLE_EFUSES) += nvmem-apple-efuses.o
> +nvmem-apple-efuses-y := apple-efuses.o
> diff --git a/drivers/nvmem/apple-efuses.c b/drivers/nvmem/apple-efuses.c
> new file mode 100644
> index 000000000000..9b7c87102104
> --- /dev/null
> +++ b/drivers/nvmem/apple-efuses.c
> @@ -0,0 +1,80 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Apple SoC eFuse driver
> + *
> + * Copyright (C) The Asahi Linux Contributors
> + */
> +
> +#include <linux/io.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/module.h>
> +#include <linux/nvmem-provider.h>
> +#include <linux/platform_device.h>
> +
> +struct apple_efuses_priv {
> + void __iomem *fuses;
> +};
> +
> +static int apple_efuses_read(void *context, unsigned int offset, void *val,
> + size_t bytes)
> +{
> + struct apple_efuses_priv *priv = context;
> + u32 *dst = val;
> +
> + while (bytes >= sizeof(u32)) {
> + *dst++ = readl_relaxed(priv->fuses + offset);
> + bytes -= sizeof(u32);
> + offset += sizeof(u32);
> + }
> +
> + return 0;
> +}
> +
> +static int apple_efuses_probe(struct platform_device *pdev)
> +{
> + struct apple_efuses_priv *priv;
> + struct resource *res;
> + struct nvmem_config config = {
> + .dev = &pdev->dev,
> + .read_only = true,
> + .reg_read = apple_efuses_read,
> + .stride = sizeof(u32),
> + .word_size = sizeof(u32),
> + .name = "apple_efuses_nvmem",
> + .id = NVMEM_DEVID_AUTO,
> + .root_only = true,
> + };
> +
> + priv = devm_kzalloc(config.dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + priv->fuses = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
> + if (IS_ERR(priv->fuses))
> + return PTR_ERR(priv->fuses);
> +
> + config.priv = priv;
> + config.size = resource_size(res);
> +
> + return PTR_ERR_OR_ZERO(devm_nvmem_register(config.dev, &config));
> +}
> +
> +static const struct of_device_id apple_efuses_of_match[] = {
> + { .compatible = "apple,efuses", },
> + {}
> +};
> +
> +MODULE_DEVICE_TABLE(of, apple_efuses_of_match);
> +
> +static struct platform_driver apple_efuses_driver = {
> + .driver = {
> + .name = "apple_efuses",
> + .of_match_table = apple_efuses_of_match,
> + },
> + .probe = apple_efuses_probe,
> +};
> +
> +module_platform_driver(apple_efuses_driver);
> +
> +MODULE_AUTHOR("Sven Peter <[email protected]>");
> +MODULE_LICENSE("GPL");
Apple SoCs come with eFuses used to store factory-programmed data
such as calibration settings for the PCIe and Type-C PHY.
Reviewed-by: Krzysztof Kozlowski <[email protected]>
Acked-by: Rob Herring <[email protected]>
Signed-off-by: Sven Peter <[email protected]>
---
v3 -> v4:
- added rob's ack
- rebased on 5.18-rc1 and split off MAINTAINER changes as requested
by Srinivas Kandagatla
v2 -> v3:
- added r-b tag
v1 -> v2:
- fixed indentation issue pointed out by Krzysztof Kozlowski
.../bindings/nvmem/apple,efuses.yaml | 50 +++++++++++++++++++
1 file changed, 50 insertions(+)
create mode 100644 Documentation/devicetree/bindings/nvmem/apple,efuses.yaml
diff --git a/Documentation/devicetree/bindings/nvmem/apple,efuses.yaml b/Documentation/devicetree/bindings/nvmem/apple,efuses.yaml
new file mode 100644
index 000000000000..5ec8f2bdb3a5
--- /dev/null
+++ b/Documentation/devicetree/bindings/nvmem/apple,efuses.yaml
@@ -0,0 +1,50 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/nvmem/apple,efuses.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Apple SoC eFuse-based NVMEM
+
+description: |
+ Apple SoCs such as the M1 contain factory-programmed eFuses used to e.g. store
+ calibration data for the PCIe and the Type-C PHY or unique chip identifiers
+ such as the ECID.
+
+maintainers:
+ - Sven Peter <[email protected]>
+
+allOf:
+ - $ref: "nvmem.yaml#"
+
+properties:
+ compatible:
+ items:
+ - enum:
+ - apple,t8103-efuses
+ - apple,t6000-efuses
+ - const: apple,efuses
+
+ reg:
+ maxItems: 1
+
+required:
+ - compatible
+ - reg
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ efuse@3d2bc000 {
+ compatible = "apple,t8103-efuses", "apple,efuses";
+ reg = <0x3d2bc000 0x1000>;
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ ecid: efuse@500 {
+ reg = <0x500 0x8>;
+ };
+ };
+
+...
--
2.25.1