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 int soc_id_rev, soc_id_version; 38 static char soc_id_str[20], soc_id_rev_str[12]; 39 static char soc_id_jep106_id_str[12]; 40 41 if (arm_smccc_get_version() < ARM_SMCCC_VERSION_1_2) 42 return 0; 43 44 soc_id_version = arm_smccc_get_soc_id_version(); 45 if (soc_id_version == SMCCC_RET_NOT_SUPPORTED) { 46 pr_info("ARCH_SOC_ID not implemented, skipping ....\n"); 47 return 0; 48 } 49 50 if (soc_id_version < 0) { 51 pr_err("Invalid SoC Version: %x\n", soc_id_version); 52 return -EINVAL; 53 } 54 55 soc_id_rev = arm_smccc_get_soc_id_revision(); 56 if (soc_id_rev < 0) { 57 pr_err("Invalid SoC Revision: %x\n", soc_id_rev); 58 return -EINVAL; 59 } 60 61 soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL); 62 if (!soc_dev_attr) 63 return -ENOMEM; 64 65 sprintf(soc_id_rev_str, "0x%08x", soc_id_rev); 66 sprintf(soc_id_jep106_id_str, "jep106:%02x%02x", 67 JEP106_BANK_CONT_CODE(soc_id_version), 68 JEP106_ID_CODE(soc_id_version)); 69 sprintf(soc_id_str, "%s:%04x", soc_id_jep106_id_str, 70 IMP_DEF_SOC_ID(soc_id_version)); 71 72 soc_dev_attr->soc_id = soc_id_str; 73 soc_dev_attr->revision = soc_id_rev_str; 74 soc_dev_attr->family = soc_id_jep106_id_str; 75 76 soc_dev = soc_device_register(soc_dev_attr); 77 if (IS_ERR(soc_dev)) { 78 kfree(soc_dev_attr); 79 return PTR_ERR(soc_dev); 80 } 81 82 pr_info("ID = %s Revision = %s\n", soc_dev_attr->soc_id, 83 soc_dev_attr->revision); 84 85 return 0; 86 } 87 module_init(smccc_soc_init); 88 89 static void __exit smccc_soc_exit(void) 90 { 91 if (soc_dev) 92 soc_device_unregister(soc_dev); 93 kfree(soc_dev_attr); 94 } 95 module_exit(smccc_soc_exit); 96