The driver provides information about the Action Semi Owl family of SoCs (S500, S700 and S900) to user space via sysfs: machine, family, soc_id, serial_number. Note the serial number is currently provided only for the S500 SoC variant. Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@xxxxxxxxx> --- drivers/soc/actions/Kconfig | 8 + drivers/soc/actions/Makefile | 1 + drivers/soc/actions/owl-socinfo.c | 152 ++++++++++++++++++ include/linux/soc/actions/owl-serial-number.h | 20 +++ 4 files changed, 181 insertions(+) create mode 100644 drivers/soc/actions/owl-socinfo.c create mode 100644 include/linux/soc/actions/owl-serial-number.h diff --git a/drivers/soc/actions/Kconfig b/drivers/soc/actions/Kconfig index 1aca2058a40c..15faade9282d 100644 --- a/drivers/soc/actions/Kconfig +++ b/drivers/soc/actions/Kconfig @@ -14,4 +14,12 @@ config OWL_PM_DOMAINS power-gating on Actions Semiconductor S500, S700 and S900 SoCs. If unsure, say 'n'. +config OWL_SOCINFO + bool "Actions Semi Owl SoC info driver" + default ARCH_ACTIONS + select SOC_BUS + help + Say 'y' here to support the Action Semiconductor Owl socinfo + driver, providing information about the SoC to user space. + endif diff --git a/drivers/soc/actions/Makefile b/drivers/soc/actions/Makefile index 4db9e7b050e5..4b2591d3089f 100644 --- a/drivers/soc/actions/Makefile +++ b/drivers/soc/actions/Makefile @@ -2,3 +2,4 @@ obj-$(CONFIG_OWL_PM_DOMAINS_HELPER) += owl-sps-helper.o obj-$(CONFIG_OWL_PM_DOMAINS) += owl-sps.o +obj-$(CONFIG_OWL_SOCINFO) += owl-socinfo.o diff --git a/drivers/soc/actions/owl-socinfo.c b/drivers/soc/actions/owl-socinfo.c new file mode 100644 index 000000000000..f28eafac3792 --- /dev/null +++ b/drivers/soc/actions/owl-socinfo.c @@ -0,0 +1,152 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Actions Semi Owl SoC information driver + * + * Copyright (c) 2021 Cristian Ciocaltea <cristian.ciocaltea@xxxxxxxxx> + */ + +#include <linux/of_address.h> +#include <linux/of_platform.h> +#include <linux/of_reserved_mem.h> +#include <linux/platform_device.h> +#include <linux/random.h> +#include <linux/soc/actions/owl-serial-number.h> +#include <linux/sys_soc.h> + +struct owl_soc_serial_rmem { + u32 low; + u32 high; +}; + +static struct owl_soc_serial_rmem *owl_socinfo_serial; + +u32 owl_get_soc_serial_low(void) +{ + return owl_socinfo_serial ? owl_socinfo_serial->low : 0; +} +EXPORT_SYMBOL_GPL(owl_get_soc_serial_low); + +u32 owl_get_soc_serial_high(void) +{ + return owl_socinfo_serial ? owl_socinfo_serial->high : 0; +} +EXPORT_SYMBOL_GPL(owl_get_soc_serial_high); + +struct owl_soc_info { + char *name; + int (*read_soc_serial)(struct device *dev); +}; + +/* + * Access SoC's serial number stored by the bootloader in DDR memory. + */ +static int owl_socinfo_read_serial_rmem(struct device *dev) +{ + struct reserved_mem *rmem; + struct device_node *np; + int ret = 0; + + np = of_find_compatible_node(NULL, NULL, "actions,owl-soc-serial"); + if (!np) + return -ENXIO; + + rmem = of_reserved_mem_lookup(np); + if (!rmem) { + dev_err(dev, "failed to acquire reserved memory region\n"); + ret = -EINVAL; + goto out_put; + } + + owl_socinfo_serial = memremap(rmem->base, rmem->size, MEMREMAP_WB); + if (!owl_socinfo_serial) + ret = -ENOMEM; + +out_put: + of_node_put(np); + return ret; +} + +static int owl_socinfo_probe(struct platform_device *pdev) +{ + const struct owl_soc_info *soc_info; + struct soc_device_attribute *soc_dev_attr; + struct soc_device *soc_dev; + const char *sn; + int ret; + + soc_info = of_device_get_match_data(&pdev->dev); + if (!soc_info) + return -ENODEV; + + soc_dev_attr = devm_kzalloc(&pdev->dev, sizeof(*soc_dev_attr), + GFP_KERNEL); + if (!soc_dev_attr) + return -ENOMEM; + + ret = of_property_read_string(of_root, "model", &soc_dev_attr->machine); + if (ret) + return ret; + + soc_dev_attr->family = "Actions Semi Owl"; + soc_dev_attr->soc_id = soc_info->name; + + if (soc_info->read_soc_serial) { + ret = soc_info->read_soc_serial(&pdev->dev); + + if (!ret) { + sn = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%08x%08x", + owl_get_soc_serial_high(), + owl_get_soc_serial_low()); + soc_dev_attr->serial_number = sn; + /* Feed the SoC unique data into entropy pool. */ + add_device_randomness(sn, 16); + } + } + + soc_dev = soc_device_register(soc_dev_attr); + if (IS_ERR(soc_dev)) + return dev_err_probe(&pdev->dev, PTR_ERR(soc_dev), + "failed to register soc device"); + + dev_info(soc_device_to_device(soc_dev), + "SoC: %s %s\n", + soc_dev_attr->family, soc_dev_attr->soc_id); + + return 0; +} + +static const struct owl_soc_info s500_soc_info = { + .name = "S500", + .read_soc_serial = owl_socinfo_read_serial_rmem, +}; + +static const struct owl_soc_info s700_soc_info = { + .name = "S700", + /* FIXME: provide read_soc_serial */ +}; + +static const struct owl_soc_info s900_soc_info = { + .name = "S900", + /* FIXME: provide read_soc_serial */ +}; + +static const struct of_device_id owl_socinfo_of_match[] = { + { .compatible = "actions,s500-soc", .data = &s500_soc_info, }, + { .compatible = "actions,s700-soc", .data = &s700_soc_info, }, + { .compatible = "actions,s900-soc", .data = &s900_soc_info, }, + { } +}; + +static struct platform_driver owl_socinfo_platform_driver = { + .probe = owl_socinfo_probe, + .driver = { + .name = "owl-socinfo", + .of_match_table = owl_socinfo_of_match, + }, +}; + +static int __init owl_socinfo_init(void) +{ + return platform_driver_register(&owl_socinfo_platform_driver); +} +subsys_initcall(owl_socinfo_init); diff --git a/include/linux/soc/actions/owl-serial-number.h b/include/linux/soc/actions/owl-serial-number.h new file mode 100644 index 000000000000..f8595417668f --- /dev/null +++ b/include/linux/soc/actions/owl-serial-number.h @@ -0,0 +1,20 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Copyright (c) 2021 Cristian Ciocaltea <cristian.ciocaltea@xxxxxxxxx> + */ + +#ifndef __SOC_ACTIONS_OWL_SERIAL_NUMBER_H__ +#define __SOC_ACTIONS_OWL_SERIAL_NUMBER_H__ + +#if IS_ENABLED(CONFIG_OWL_SOCINFO) +u32 owl_get_soc_serial_low(void); +u32 owl_get_soc_serial_high(void); +#else +static inline u32 owl_get_soc_serial_low(void) +{ return 0; } + +static inline u32 owl_get_soc_serial_high(void) +{ return 0; } +#endif /* CONFIG_OWL_SOCINFO */ + +#endif /* __SOC_ACTIONS_OWL_SERIAL_NUMBER_H__ */ -- 2.31.1