summaryrefslogtreecommitdiffstats
path: root/arch/s390/kernel/irq.c
blob: e204f9597aafa1df6fd51fe3a971ff41b3272f3d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
/*
 *    Copyright IBM Corp. 2004,2010
 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
 *		 Thomas Spatzier (tspat@de.ibm.com)
 *
 * This file contains interrupt related functions.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/kernel_stat.h>
#include <linux/interrupt.h>
#include <linux/seq_file.h>
#include <linux/cpu.h>
#include <linux/proc_fs.h>
#include <linux/profile.h>

struct irq_class {
	char *name;
	char *desc;
};

static const struct irq_class intrclass_names[] = {
	{.name = "EXT" },
	{.name = "I/O" },
	{.name = "CLK", .desc = "[EXT] Clock Comparator" },
	{.name = "IPI", .desc = "[EXT] Signal Processor" },
	{.name = "TMR", .desc = "[EXT] CPU Timer" },
	{.name = "TAL", .desc = "[EXT] Timing Alert" },
	{.name = "PFL", .desc = "[EXT] Pseudo Page Fault" },
	{.name = "DSD", .desc = "[EXT] DASD Diag" },
	{.name = "VRT", .desc = "[EXT] Virtio" },
	{.name = "SCP", .desc = "[EXT] Service Call" },
	{.name = "IUC", .desc = "[EXT] IUCV" },
	{.name = "CPM", .desc = "[EXT] CPU Measurement" },
	{.name = "QAI", .desc = "[I/O] QDIO Adapter Interrupt" },
	{.name = "QDI", .desc = "[I/O] QDIO Interrupt" },
	{.name = "DAS", .desc = "[I/O] DASD" },
	{.name = "C15", .desc = "[I/O] 3215" },
	{.name = "C70", .desc = "[I/O] 3270" },
	{.name = "TAP", .desc = "[I/O] Tape" },
	{.name = "VMR", .desc = "[I/O] Unit Record Devices" },
	{.name = "LCS", .desc = "[I/O] LCS" },
	{.name = "CLW", .desc = "[I/O] CLAW" },
	{.name = "CTC", .desc = "[I/O] CTC" },
	{.name = "APB", .desc = "[I/O] AP Bus" },
	{.name = "NMI", .desc = "[NMI] Machine Check" },
};

/*
 * show_interrupts is needed by /proc/interrupts.
 */
int show_interrupts(struct seq_file *p, void *v)
{
	int i = *(loff_t *) v, j;

	get_online_cpus();
	if (i == 0) {
		seq_puts(p, "           ");
		for_each_online_cpu(j)
			seq_printf(p, "CPU%d       ",j);
		seq_putc(p, '\n');
	}

	if (i < NR_IRQS) {
		seq_printf(p, "%s: ", intrclass_names[i].name);
#ifndef CONFIG_SMP
		seq_printf(p, "%10u ", kstat_irqs(i));
#else
		for_each_online_cpu(j)
			seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
#endif
		if (intrclass_names[i].desc)
			seq_printf(p, "  %s", intrclass_names[i].desc);
                seq_putc(p, '\n');
        }
	put_online_cpus();
        return 0;
}

/*
 * For compatibilty only. S/390 specific setup of interrupts et al. is done
 * much later in init_channel_subsystem().
 */
void __init
init_IRQ(void)
{
	/* nothing... */
}

/*
 * Switch to the asynchronous interrupt stack for softirq execution.
 */
asmlinkage void do_softirq(void)
{
	unsigned long flags, old, new;

	if (in_interrupt())
		return;

	local_irq_save(flags);

	if (local_softirq_pending()) {
		/* Get current stack pointer. */
		asm volatile("la %0,0(15)" : "=a" (old));
		/* Check against async. stack address range. */
		new = S390_lowcore.async_stack;
		if (((new - old) >> (PAGE_SHIFT + THREAD_ORDER)) != 0) {
			/* Need to switch to the async. stack. */
			new -= STACK_FRAME_OVERHEAD;
			((struct stack_frame *) new)->back_chain = old;

			asm volatile("   la    15,0(%0)\n"
				     "   basr  14,%2\n"
				     "   la    15,0(%1)\n"
				     : : "a" (new), "a" (old),
				         "a" (__do_softirq)
				     : "0", "1", "2", "3", "4", "5", "14",
				       "cc", "memory" );
		} else
			/* We are already on the async stack. */
			__do_softirq();
	}

	local_irq_restore(flags);
}

#ifdef CONFIG_PROC_FS
void init_irq_proc(void)
{
	struct proc_dir_entry *root_irq_dir;

	root_irq_dir = proc_mkdir("irq", NULL);
	create_prof_cpu_mask(root_irq_dir);
}
#endif
OpenPOWER on IntegriCloud