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 <linux/sched/task_stack.h> 12 #include <asm/cpu_ops.h> 13 #include <asm/sbi.h> 14 #include <asm/smp.h> 15 16 const struct cpu_operations *cpu_ops[NR_CPUS] __ro_after_init; 17 18 void *__cpu_up_stack_pointer[NR_CPUS] __section(".data"); 19 void *__cpu_up_task_pointer[NR_CPUS] __section(".data"); 20 21 extern const struct cpu_operations cpu_ops_sbi; 22 extern const struct cpu_operations cpu_ops_spinwait; 23 24 void cpu_update_secondary_bootdata(unsigned int cpuid, 25 struct task_struct *tidle) 26 { 27 int hartid = cpuid_to_hartid_map(cpuid); 28 29 /* Make sure tidle is updated */ 30 smp_mb(); 31 WRITE_ONCE(__cpu_up_stack_pointer[hartid], 32 task_stack_page(tidle) + THREAD_SIZE); 33 WRITE_ONCE(__cpu_up_task_pointer[hartid], tidle); 34 } 35 36 void __init cpu_set_ops(int cpuid) 37 { 38 #if IS_ENABLED(CONFIG_RISCV_SBI) 39 if (sbi_probe_extension(SBI_EXT_HSM) > 0) { 40 if (!cpuid) 41 pr_info("SBI v0.2 HSM extension detected\n"); 42 cpu_ops[cpuid] = &cpu_ops_sbi; 43 } else 44 #endif 45 cpu_ops[cpuid] = &cpu_ops_spinwait; 46 } 47