1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright 2020 Arm Limited 4 */ 5 6 #define pr_fmt(fmt) "SMCCC: SOC_ID: " fmt 7 8 #include <linux/arm-smccc.h> 9 #include <linux/bitfield.h> 10 #include <linux/device.h> 11 #include <linux/module.h> 12 #include <linux/kernel.h> 13 #include <linux/slab.h> 14 #include <linux/sys_soc.h> 15 16 #define SMCCC_SOC_ID_JEP106_BANK_IDX_MASK GENMASK(30, 24) 17 /* 18 * As per the SMC Calling Convention specification v1.2 (ARM DEN 0028C) 19 * Section 7.4 SMCCC_ARCH_SOC_ID bits[23:16] are JEP-106 identification 20 * code with parity bit for the SiP. We can drop the parity bit. 21 */ 22 #define SMCCC_SOC_ID_JEP106_ID_CODE_MASK GENMASK(22, 16) 23 #define SMCCC_SOC_ID_IMP_DEF_SOC_ID_MASK GENMASK(15, 0) 24 25 #define JEP106_BANK_CONT_CODE(x) \ 26 (u8)(FIELD_GET(SMCCC_SOC_ID_JEP106_BANK_IDX_MASK, (x))) 27 #define JEP106_ID_CODE(x) \ 28 (u8)(FIELD_GET(SMCCC_SOC_ID_JEP106_ID_CODE_MASK, (x))) 29 #define IMP_DEF_SOC_ID(x) \ 30 (u16)(FIELD_GET(SMCCC_SOC_ID_IMP_DEF_SOC_ID_MASK, (x))) 31 32 static struct soc_device *soc_dev; 33 static struct soc_device_attribute *soc_dev_attr; 34 35 static int __init smccc_soc_init(void) 36 { 37 struct arm_smccc_res res; 38 int soc_id_rev, soc_id_version; 39 static char soc_id_str[20], soc_id_rev_str[12]; 40 static char soc_id_jep106_id_str[12]; 41 42 if (arm_smccc_get_version() < ARM_SMCCC_VERSION_1_2) 43 return 0; 44 45 soc_id_version = arm_smccc_get_soc_id_version(); 46 if (soc_id_version == SMCCC_RET_NOT_SUPPORTED) { 47 pr_info("ARCH_SOC_ID not implemented, skipping ....\n"); 48 return 0; 49 } 50 51 if (soc_id_version < 0) { 52 pr_err("ARCH_SOC_ID(0) returned error: %lx\n", res.a0); 53 return -EINVAL; 54 } 55 56 soc_id_rev = arm_smccc_get_soc_id_revision(); 57 if (soc_id_rev < 0) { 58 pr_err("ARCH_SOC_ID(1) returned error: %lx\n", res.a0); 59 return -EINVAL; 60 } 61 62 soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL); 63 if (!soc_dev_attr) 64 return -ENOMEM; 65 66 sprintf(soc_id_rev_str, "0x%08x", soc_id_rev); 67 sprintf(soc_id_jep106_id_str, "jep106:%02x%02x", 68 JEP106_BANK_CONT_CODE(soc_id_version), 69 JEP106_ID_CODE(soc_id_version)); 70 sprintf(soc_id_str, "%s:%04x", soc_id_jep106_id_str, 71 IMP_DEF_SOC_ID(soc_id_version)); 72 73 soc_dev_attr->soc_id = soc_id_str; 74 soc_dev_attr->revision = soc_id_rev_str; 75 soc_dev_attr->family = soc_id_jep106_id_str; 76 77 soc_dev = soc_device_register(soc_dev_attr); 78 if (IS_ERR(soc_dev)) { 79 kfree(soc_dev_attr); 80 return PTR_ERR(soc_dev); 81 } 82 83 pr_info("ID = %s Revision = %s\n", soc_dev_attr->soc_id, 84 soc_dev_attr->revision); 85 86 return 0; 87 } 88 module_init(smccc_soc_init); 89 90 static void __exit smccc_soc_exit(void) 91 { 92 if (soc_dev) 93 soc_device_unregister(soc_dev); 94 kfree(soc_dev_attr); 95 } 96 module_exit(smccc_soc_exit); 97