1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * LoongArch specific sysrq operations. 4 * 5 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited 6 */ 7 #include <linux/init.h> 8 #include <linux/smp.h> 9 #include <linux/spinlock.h> 10 #include <linux/sysrq.h> 11 #include <linux/workqueue.h> 12 13 #include <asm/cpu-features.h> 14 #include <asm/tlb.h> 15 16 /* 17 * Dump TLB entries on all CPUs. 18 */ 19 20 static DEFINE_SPINLOCK(show_lock); 21 22 static void sysrq_tlbdump_single(void *dummy) 23 { 24 unsigned long flags; 25 26 spin_lock_irqsave(&show_lock, flags); 27 28 pr_info("CPU%d:\n", smp_processor_id()); 29 dump_tlb_regs(); 30 pr_info("\n"); 31 dump_tlb_all(); 32 pr_info("\n"); 33 34 spin_unlock_irqrestore(&show_lock, flags); 35 } 36 37 #ifdef CONFIG_SMP 38 static void sysrq_tlbdump_othercpus(struct work_struct *dummy) 39 { 40 smp_call_function(sysrq_tlbdump_single, NULL, 0); 41 } 42 43 static DECLARE_WORK(sysrq_tlbdump, sysrq_tlbdump_othercpus); 44 #endif 45 46 static void sysrq_handle_tlbdump(u8 key) 47 { 48 sysrq_tlbdump_single(NULL); 49 #ifdef CONFIG_SMP 50 schedule_work(&sysrq_tlbdump); 51 #endif 52 } 53 54 static struct sysrq_key_op sysrq_tlbdump_op = { 55 .handler = sysrq_handle_tlbdump, 56 .help_msg = "show-tlbs(x)", 57 .action_msg = "Show TLB entries", 58 .enable_mask = SYSRQ_ENABLE_DUMP, 59 }; 60 61 static int __init loongarch_sysrq_init(void) 62 { 63 return register_sysrq_key('x', &sysrq_tlbdump_op); 64 } 65 arch_initcall(loongarch_sysrq_init); 66