From f78451012b9e159afdba31c3eb69f223a9f42adc Mon Sep 17 00:00:00 2001 From: Michael Walle Date: Sun, 20 Feb 2022 15:15:23 +0000 Subject: [PATCH] nvmem: add driver for Layerscape SFP (Security Fuse Processor) Add support for the Security Fuse Processor found on Layerscape SoCs. This driver implements basic read access. Signed-off-by: Michael Walle Signed-off-by: Srinivas Kandagatla Link: https://lore.kernel.org/r/20220220151527.17216-10-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman --- drivers/nvmem/Kconfig | 12 +++++ drivers/nvmem/Makefile | 2 + drivers/nvmem/layerscape-sfp.c | 89 ++++++++++++++++++++++++++++++++++ 3 files changed, 103 insertions(+) create mode 100644 drivers/nvmem/layerscape-sfp.c --- a/drivers/nvmem/Kconfig +++ b/drivers/nvmem/Kconfig @@ -300,4 +300,16 @@ config NVMEM_BRCM_NVRAM This driver provides support for Broadcom's NVRAM that can be accessed using I/O mapping. +config NVMEM_LAYERSCAPE_SFP + tristate "Layerscape SFP (Security Fuse Processor) support" + depends on ARCH_LAYERSCAPE || COMPILE_TEST + depends on HAS_IOMEM + help + This driver provides support to read the eFuses on Freescale + Layerscape SoC's. For example, the vendor provides a per part + unique ID there. + + This driver can also be built as a module. If so, the module + will be called layerscape-sfp. + endif --- a/drivers/nvmem/Makefile +++ b/drivers/nvmem/Makefile @@ -61,3 +61,5 @@ obj-$(CONFIG_NVMEM_RMEM) += nvmem-rmem. nvmem-rmem-y := rmem.o obj-$(CONFIG_NVMEM_BRCM_NVRAM) += nvmem_brcm_nvram.o nvmem_brcm_nvram-y := brcm_nvram.o +obj-$(CONFIG_NVMEM_LAYERSCAPE_SFP) += nvmem-layerscape-sfp.o +nvmem-layerscape-sfp-y := layerscape-sfp.o --- /dev/null +++ b/drivers/nvmem/layerscape-sfp.c @@ -0,0 +1,89 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Layerscape SFP driver + * + * Copyright (c) 2022 Michael Walle + * + */ + +#include +#include +#include +#include +#include +#include +#include + +#define LAYERSCAPE_SFP_OTP_OFFSET 0x0200 + +struct layerscape_sfp_priv { + void __iomem *base; +}; + +struct layerscape_sfp_data { + int size; +}; + +static int layerscape_sfp_read(void *context, unsigned int offset, void *val, + size_t bytes) +{ + struct layerscape_sfp_priv *priv = context; + + memcpy_fromio(val, priv->base + LAYERSCAPE_SFP_OTP_OFFSET + offset, + bytes); + + return 0; +} + +static struct nvmem_config layerscape_sfp_nvmem_config = { + .name = "fsl-sfp", + .reg_read = layerscape_sfp_read, +}; + +static int layerscape_sfp_probe(struct platform_device *pdev) +{ + const struct layerscape_sfp_data *data; + struct layerscape_sfp_priv *priv; + struct nvmem_device *nvmem; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->base)) + return PTR_ERR(priv->base); + + data = device_get_match_data(&pdev->dev); + + layerscape_sfp_nvmem_config.size = data->size; + layerscape_sfp_nvmem_config.dev = &pdev->dev; + layerscape_sfp_nvmem_config.priv = priv; + + nvmem = devm_nvmem_register(&pdev->dev, &layerscape_sfp_nvmem_config); + + return PTR_ERR_OR_ZERO(nvmem); +} + +static const struct layerscape_sfp_data ls1028a_data = { + .size = 0x88, +}; + +static const struct of_device_id layerscape_sfp_dt_ids[] = { + { .compatible = "fsl,ls1028a-sfp", .data = &ls1028a_data }, + {}, +}; +MODULE_DEVICE_TABLE(of, layerscape_sfp_dt_ids); + +static struct platform_driver layerscape_sfp_driver = { + .probe = layerscape_sfp_probe, + .driver = { + .name = "layerscape_sfp", + .of_match_table = layerscape_sfp_dt_ids, + }, +}; +module_platform_driver(layerscape_sfp_driver); + +MODULE_AUTHOR("Michael Walle "); +MODULE_DESCRIPTION("Layerscape Security Fuse Processor driver"); +MODULE_LICENSE("GPL");