1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * MIPS specific sysrq operations.
4 *
5 * Copyright (C) 2015 Imagination Technologies Ltd.
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/mipsregs.h>
15 #include <asm/tlbdebug.h>
16
17 /*
18 * Dump TLB entries on all CPUs.
19 */
20
21 static DEFINE_SPINLOCK(show_lock);
22
sysrq_tlbdump_single(void * dummy)23 static void sysrq_tlbdump_single(void *dummy)
24 {
25 unsigned long flags;
26
27 spin_lock_irqsave(&show_lock, flags);
28
29 pr_info("CPU%d:\n", smp_processor_id());
30 dump_tlb_regs();
31 pr_info("\n");
32 dump_tlb_all();
33 pr_info("\n");
34
35 spin_unlock_irqrestore(&show_lock, flags);
36 }
37
38 #ifdef CONFIG_SMP
sysrq_tlbdump_othercpus(struct work_struct * dummy)39 static void sysrq_tlbdump_othercpus(struct work_struct *dummy)
40 {
41 smp_call_function(sysrq_tlbdump_single, NULL, 0);
42 }
43
44 static DECLARE_WORK(sysrq_tlbdump, sysrq_tlbdump_othercpus);
45 #endif
46
sysrq_handle_tlbdump(u8 key)47 static void sysrq_handle_tlbdump(u8 key)
48 {
49 sysrq_tlbdump_single(NULL);
50 #ifdef CONFIG_SMP
51 schedule_work(&sysrq_tlbdump);
52 #endif
53 }
54
55 static const struct sysrq_key_op sysrq_tlbdump_op = {
56 .handler = sysrq_handle_tlbdump,
57 .help_msg = "show-tlbs(x)",
58 .action_msg = "Show TLB entries",
59 .enable_mask = SYSRQ_ENABLE_DUMP,
60 };
61
mips_sysrq_init(void)62 static int __init mips_sysrq_init(void)
63 {
64 return register_sysrq_key('x', &sysrq_tlbdump_op);
65 }
66 arch_initcall(mips_sysrq_init);
67