1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2020 Western Digital Corporation or its affiliates. 4 */ 5 6 #include <linux/errno.h> 7 #include <linux/mm.h> 8 #include <linux/of.h> 9 #include <linux/string.h> 10 #include <linux/sched.h> 11 #include <asm/cpu_ops.h> 12 #include <asm/sbi.h> 13 #include <asm/smp.h> 14 15 const struct cpu_operations *cpu_ops[NR_CPUS] __ro_after_init; 16 17 extern const struct cpu_operations cpu_ops_sbi; 18 #ifdef CONFIG_RISCV_BOOT_SPINWAIT 19 extern const struct cpu_operations cpu_ops_spinwait; 20 #else 21 const struct cpu_operations cpu_ops_spinwait = { 22 .name = "", 23 .cpu_prepare = NULL, 24 .cpu_start = NULL, 25 }; 26 #endif 27 28 void __init cpu_set_ops(int cpuid) 29 { 30 #if IS_ENABLED(CONFIG_RISCV_SBI) 31 if (sbi_probe_extension(SBI_EXT_HSM) > 0) { 32 if (!cpuid) 33 pr_info("SBI HSM extension detected\n"); 34 cpu_ops[cpuid] = &cpu_ops_sbi; 35 } else 36 #endif 37 cpu_ops[cpuid] = &cpu_ops_spinwait; 38 } 39