diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-devices-soc | 30 | ||||
| -rw-r--r-- | drivers/firmware/smccc/Kconfig | 9 | ||||
| -rw-r--r-- | drivers/firmware/smccc/Makefile | 1 | ||||
| -rw-r--r-- | drivers/firmware/smccc/soc_id.c | 114 | ||||
| -rw-r--r-- | include/linux/arm-smccc.h | 5 |
5 files changed, 159 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-soc b/Documentation/ABI/testing/sysfs-devices-soc index ba3a3fac0ee1..ea999e292f11 100644 --- a/Documentation/ABI/testing/sysfs-devices-soc +++ b/Documentation/ABI/testing/sysfs-devices-soc @@ -26,6 +26,30 @@ Description: Read-only attribute common to all SoCs. Contains SoC family name (e.g. DB8500). + On many of ARM based silicon with SMCCC v1.2+ compliant firmware + this will contain the JEDEC JEP106 manufacturer’s identification + code. The format is "jep106:XXYY" where XX is identity code and + YY is continuation code. + + This manufacturer’s identification code is defined by one + or more eight (8) bit fields, each consisting of seven (7) + data bits plus one (1) odd parity bit. It is a single field, + limiting the possible number of vendors to 126. To expand + the maximum number of identification codes, a continuation + scheme has been defined. + + The specified mechanism is that an identity code of 0x7F + represents the "continuation code" and implies the presence + of an additional identity code field, and this mechanism + may be extended to multiple continuation codes followed + by the manufacturer's identity code. + + For example, ARM has identity code 0x7F 0x7F 0x7F 0x7F 0x3B, + which is code 0x3B on the fifth 'page'. This is shortened + as JEP106 identity code of 0x3B and a continuation code of + 0x4 to represent the four continuation codes preceding the + identity code. + What: /sys/devices/socX/serial_number Date: January 2019 contact: Bjorn Andersson <bjorn.andersson@linaro.org> @@ -40,6 +64,12 @@ Description: Read-only attribute supported by most SoCs. In the case of ST-Ericsson's chips this contains the SoC serial number. + On many of ARM based silicon with SMCCC v1.2+ compliant firmware + this will contain the SOC ID appended to the family attribute + to ensure there is no conflict in this namespace across various + vendors. The format is "jep106:XXYY:ZZZZ" where XX is identity + code, YY is continuation code and ZZZZ is the SOC ID. + What: /sys/devices/socX/revision Date: January 2012 contact: Lee Jones <lee.jones@linaro.org> diff --git a/drivers/firmware/smccc/Kconfig b/drivers/firmware/smccc/Kconfig index 27b675d76235..15e7466179a6 100644 --- a/drivers/firmware/smccc/Kconfig +++ b/drivers/firmware/smccc/Kconfig @@ -14,3 +14,12 @@ config HAVE_ARM_SMCCC_DISCOVERY to add SMCCC discovery mechanism though the PSCI firmware implementation of PSCI_FEATURES(SMCCC_VERSION) which returns success on firmware compliant to SMCCC v1.1 and above. + +config ARM_SMCCC_SOC_ID + bool "SoC bus device for the ARM SMCCC SOC_ID" + depends on HAVE_ARM_SMCCC_DISCOVERY + default y + select SOC_BUS + help + Include support for the SoC bus on the ARM SMCCC firmware based + platforms providing some sysfs information about the SoC variant. diff --git a/drivers/firmware/smccc/Makefile b/drivers/firmware/smccc/Makefile index 6f369fe3f0b9..72ab84042832 100644 --- a/drivers/firmware/smccc/Makefile +++ b/drivers/firmware/smccc/Makefile @@ -1,3 +1,4 @@ # SPDX-License-Identifier: GPL-2.0 # obj-$(CONFIG_HAVE_ARM_SMCCC_DISCOVERY) += smccc.o +obj-$(CONFIG_ARM_SMCCC_SOC_ID) += soc_id.o diff --git a/drivers/firmware/smccc/soc_id.c b/drivers/firmware/smccc/soc_id.c new file mode 100644 index 000000000000..581aa5e9b077 --- /dev/null +++ b/drivers/firmware/smccc/soc_id.c @@ -0,0 +1,114 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2020 Arm Limited + */ + +#define pr_fmt(fmt) "SMCCC: SOC_ID: " fmt + +#include <linux/arm-smccc.h> +#include <linux/bitfield.h> +#include <linux/device.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/sys_soc.h> + +#define SMCCC_SOC_ID_JEP106_BANK_IDX_MASK GENMASK(30, 24) +/* + * As per the SMC Calling Convention specification v1.2 (ARM DEN 0028C) + * Section 7.4 SMCCC_ARCH_SOC_ID bits[23:16] are JEP-106 identification + * code with parity bit for the SiP. We can drop the parity bit. + */ +#define SMCCC_SOC_ID_JEP106_ID_CODE_MASK GENMASK(22, 16) +#define SMCCC_SOC_ID_IMP_DEF_SOC_ID_MASK GENMASK(15, 0) + +#define JEP106_BANK_CONT_CODE(x) \ + (u8)(FIELD_GET(SMCCC_SOC_ID_JEP106_BANK_IDX_MASK, (x))) +#define JEP106_ID_CODE(x) \ + (u8)(FIELD_GET(SMCCC_SOC_ID_JEP106_ID_CODE_MASK, (x))) +#define IMP_DEF_SOC_ID(x) \ + (u16)(FIELD_GET(SMCCC_SOC_ID_IMP_DEF_SOC_ID_MASK, (x))) + +static struct soc_device *soc_dev; +static struct soc_device_attribute *soc_dev_attr; + +static int __init smccc_soc_init(void) +{ + struct arm_smccc_res res; + int soc_id_rev, soc_id_version; + static char soc_id_str[20], soc_id_rev_str[12]; + static char soc_id_jep106_id_str[12]; + + if (arm_smccc_get_version() < ARM_SMCCC_VERSION_1_2) + return 0; + + if (arm_smccc_1_1_get_conduit() == SMCCC_CONDUIT_NONE) { + pr_err("%s: invalid SMCCC conduit\n", __func__); + return -EOPNOTSUPP; + } + + arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, + ARM_SMCCC_ARCH_SOC_ID, &res); + + if (res.a0 == SMCCC_RET_NOT_SUPPORTED) { + pr_info("ARCH_SOC_ID not implemented, skipping ....\n"); + return 0; + } + + if ((int)res.a0 < 0) { + pr_info("ARCH_FEATURES(ARCH_SOC_ID) returned error: %lx\n", + res.a0); + return -EINVAL; + } + + arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_SOC_ID, 0, &res); + if ((int)res.a0 < 0) { + pr_err("ARCH_SOC_ID(0) returned error: %lx\n", res.a0); + return -EINVAL; + } + + soc_id_version = res.a0; + + arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_SOC_ID, 1, &res); + if ((int)res.a0 < 0) { + pr_err("ARCH_SOC_ID(1) returned error: %lx\n", res.a0); + return -EINVAL; + } + + soc_id_rev = res.a0; + + soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL); + if (!soc_dev_attr) + return -ENOMEM; + + sprintf(soc_id_rev_str, "0x%08x", soc_id_rev); + sprintf(soc_id_jep106_id_str, "jep106:%02x%02x", + JEP106_BANK_CONT_CODE(soc_id_version), + JEP106_ID_CODE(soc_id_version)); + sprintf(soc_id_str, "%s:%04x", soc_id_jep106_id_str, + IMP_DEF_SOC_ID(soc_id_version)); + + soc_dev_attr->soc_id = soc_id_str; + soc_dev_attr->revision = soc_id_rev_str; + soc_dev_attr->family = soc_id_jep106_id_str; + + soc_dev = soc_device_register(soc_dev_attr); + if (IS_ERR(soc_dev)) { + kfree(soc_dev_attr); + return PTR_ERR(soc_dev); + } + + pr_info("ID = %s Revision = %s\n", soc_dev_attr->soc_id, + soc_dev_attr->revision); + + return 0; +} +module_init(smccc_soc_init); + +static void __exit smccc_soc_exit(void) +{ + if (soc_dev) + soc_device_unregister(soc_dev); + kfree(soc_dev_attr); +} +module_exit(smccc_soc_exit); diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h index 56d6a5c6e353..8254e11ea857 100644 --- a/include/linux/arm-smccc.h +++ b/include/linux/arm-smccc.h @@ -71,6 +71,11 @@ ARM_SMCCC_SMC_32, \ 0, 1) +#define ARM_SMCCC_ARCH_SOC_ID \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_32, \ + 0, 2) + #define ARM_SMCCC_ARCH_WORKAROUND_1 \ ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ ARM_SMCCC_SMC_32, \ |