summaryrefslogtreecommitdiffstats
path: root/arch/x86_64/kernel/genapic_flat.c
blob: ecb01eefdd27b4b63c14352f0fff569ef9d60eca (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
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
/*
 * Copyright 2004 James Cleverdon, IBM.
 * Subject to the GNU Public License, v.2
 *
 * Flat APIC subarch code.
 *
 * Hacked for x86-64 by James Cleverdon from i386 architecture code by
 * Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and
 * James Cleverdon.
 */
#include <linux/errno.h>
#include <linux/threads.h>
#include <linux/cpumask.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/ctype.h>
#include <linux/init.h>
#include <asm/smp.h>
#include <asm/ipi.h>
#include <asm/genapic.h>

static cpumask_t flat_target_cpus(void)
{
	return cpu_online_map;
}

static cpumask_t flat_vector_allocation_domain(int cpu)
{
	/* Careful. Some cpus do not strictly honor the set of cpus
	 * specified in the interrupt destination when using lowest
	 * priority interrupt delivery mode.
	 *
	 * In particular there was a hyperthreading cpu observed to
	 * deliver interrupts to the wrong hyperthread when only one
	 * hyperthread was specified in the interrupt desitination.
	 */
	cpumask_t domain = { { [0] = APIC_ALL_CPUS, } };
	return domain;
}

/*
 * Set up the logical destination ID.
 *
 * Intel recommends to set DFR, LDR and TPR before enabling
 * an APIC.  See e.g. "AP-388 82489DX User's Manual" (Intel
 * document number 292116).  So here it goes...
 */
static void flat_init_apic_ldr(void)
{
	unsigned long val;
	unsigned long num, id;

	num = smp_processor_id();
	id = 1UL << num;
	x86_cpu_to_log_apicid[num] = id;
	apic_write(APIC_DFR, APIC_DFR_FLAT);
	val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
	val |= SET_APIC_LOGICAL_ID(id);
	apic_write(APIC_LDR, val);
}

static void flat_send_IPI_mask(cpumask_t cpumask, int vector)
{
	unsigned long mask = cpus_addr(cpumask)[0];
	unsigned long flags;

	local_irq_save(flags);
	__send_IPI_dest_field(mask, vector, APIC_DEST_LOGICAL);
	local_irq_restore(flags);
}

static void flat_send_IPI_allbutself(int vector)
{
#ifdef	CONFIG_HOTPLUG_CPU
	int hotplug = 1;
#else
	int hotplug = 0;
#endif
	if (hotplug || vector == NMI_VECTOR) {
		cpumask_t allbutme = cpu_online_map;

		cpu_clear(smp_processor_id(), allbutme);

		if (!cpus_empty(allbutme))
			flat_send_IPI_mask(allbutme, vector);
	} else if (num_online_cpus() > 1) {
		__send_IPI_shortcut(APIC_DEST_ALLBUT, vector,APIC_DEST_LOGICAL);
	}
}

static void flat_send_IPI_all(int vector)
{
	if (vector == NMI_VECTOR)
		flat_send_IPI_mask(cpu_online_map, vector);
	else
		__send_IPI_shortcut(APIC_DEST_ALLINC, vector, APIC_DEST_LOGICAL);
}

static int flat_apic_id_registered(void)
{
	return physid_isset(GET_APIC_ID(apic_read(APIC_ID)), phys_cpu_present_map);
}

static unsigned int flat_cpu_mask_to_apicid(cpumask_t cpumask)
{
	return cpus_addr(cpumask)[0] & APIC_ALL_CPUS;
}

static unsigned int phys_pkg_id(int index_msb)
{
	return hard_smp_processor_id() >> index_msb;
}

struct genapic apic_flat =  {
	.name = "flat",
	.int_delivery_mode = dest_LowestPrio,
	.int_dest_mode = (APIC_DEST_LOGICAL != 0),
	.target_cpus = flat_target_cpus,
	.vector_allocation_domain = flat_vector_allocation_domain,
	.apic_id_registered = flat_apic_id_registered,
	.init_apic_ldr = flat_init_apic_ldr,
	.send_IPI_all = flat_send_IPI_all,
	.send_IPI_allbutself = flat_send_IPI_allbutself,
	.send_IPI_mask = flat_send_IPI_mask,
	.cpu_mask_to_apicid = flat_cpu_mask_to_apicid,
	.phys_pkg_id = phys_pkg_id,
};

/*
 * Physflat mode is used when there are more than 8 CPUs on a AMD system.
 * We cannot use logical delivery in this case because the mask
 * overflows, so use physical mode.
 */

static cpumask_t physflat_target_cpus(void)
{
	return cpu_online_map;
}

static cpumask_t physflat_vector_allocation_domain(int cpu)
{
	cpumask_t domain = CPU_MASK_NONE;
	cpu_set(cpu, domain);
	return domain;
}


static void physflat_send_IPI_mask(cpumask_t cpumask, int vector)
{
	send_IPI_mask_sequence(cpumask, vector);
}

static void physflat_send_IPI_allbutself(int vector)
{
	cpumask_t allbutme = cpu_online_map;

	cpu_clear(smp_processor_id(), allbutme);
	physflat_send_IPI_mask(allbutme, vector);
}

static void physflat_send_IPI_all(int vector)
{
	physflat_send_IPI_mask(cpu_online_map, vector);
}

static unsigned int physflat_cpu_mask_to_apicid(cpumask_t cpumask)
{
	int cpu;

	/*
	 * We're using fixed IRQ delivery, can only return one phys APIC ID.
	 * May as well be the first.
	 */
	cpu = first_cpu(cpumask);
	if ((unsigned)cpu < NR_CPUS)
		return x86_cpu_to_apicid[cpu];
	else
		return BAD_APICID;
}

struct genapic apic_physflat =  {
	.name = "physical flat",
	.int_delivery_mode = dest_Fixed,
	.int_dest_mode = (APIC_DEST_PHYSICAL != 0),
	.target_cpus = physflat_target_cpus,
	.vector_allocation_domain = physflat_vector_allocation_domain,
	.apic_id_registered = flat_apic_id_registered,
	.init_apic_ldr = flat_init_apic_ldr,/*not needed, but shouldn't hurt*/
	.send_IPI_all = physflat_send_IPI_all,
	.send_IPI_allbutself = physflat_send_IPI_allbutself,
	.send_IPI_mask = physflat_send_IPI_mask,
	.cpu_mask_to_apicid = physflat_cpu_mask_to_apicid,
	.phys_pkg_id = phys_pkg_id,
};
OpenPOWER on IntegriCloud