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
sysrq_tlbdump_single(void * dummy)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
sysrq_tlbdump_othercpus(struct work_struct * dummy)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
sysrq_handle_tlbdump(u8 key)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
loongarch_sysrq_init(void)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