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Diffstat (limited to 'arch/x86/include/asm/ipi.h')
-rw-r--r-- | arch/x86/include/asm/ipi.h | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/arch/x86/include/asm/ipi.h b/arch/x86/include/asm/ipi.h new file mode 100644 index 000000000000..f89dffb28aa9 --- /dev/null +++ b/arch/x86/include/asm/ipi.h | |||
@@ -0,0 +1,138 @@ | |||
1 | #ifndef _ASM_X86_IPI_H | ||
2 | #define _ASM_X86_IPI_H | ||
3 | |||
4 | /* | ||
5 | * Copyright 2004 James Cleverdon, IBM. | ||
6 | * Subject to the GNU Public License, v.2 | ||
7 | * | ||
8 | * Generic APIC InterProcessor Interrupt code. | ||
9 | * | ||
10 | * Moved to include file by James Cleverdon from | ||
11 | * arch/x86-64/kernel/smp.c | ||
12 | * | ||
13 | * Copyrights from kernel/smp.c: | ||
14 | * | ||
15 | * (c) 1995 Alan Cox, Building #3 <alan@redhat.com> | ||
16 | * (c) 1998-99, 2000 Ingo Molnar <mingo@redhat.com> | ||
17 | * (c) 2002,2003 Andi Kleen, SuSE Labs. | ||
18 | * Subject to the GNU Public License, v.2 | ||
19 | */ | ||
20 | |||
21 | #include <asm/hw_irq.h> | ||
22 | #include <asm/apic.h> | ||
23 | #include <asm/smp.h> | ||
24 | |||
25 | /* | ||
26 | * the following functions deal with sending IPIs between CPUs. | ||
27 | * | ||
28 | * We use 'broadcast', CPU->CPU IPIs and self-IPIs too. | ||
29 | */ | ||
30 | |||
31 | static inline unsigned int __prepare_ICR(unsigned int shortcut, int vector, | ||
32 | unsigned int dest) | ||
33 | { | ||
34 | unsigned int icr = shortcut | dest; | ||
35 | |||
36 | switch (vector) { | ||
37 | default: | ||
38 | icr |= APIC_DM_FIXED | vector; | ||
39 | break; | ||
40 | case NMI_VECTOR: | ||
41 | icr |= APIC_DM_NMI; | ||
42 | break; | ||
43 | } | ||
44 | return icr; | ||
45 | } | ||
46 | |||
47 | static inline int __prepare_ICR2(unsigned int mask) | ||
48 | { | ||
49 | return SET_APIC_DEST_FIELD(mask); | ||
50 | } | ||
51 | |||
52 | static inline void __xapic_wait_icr_idle(void) | ||
53 | { | ||
54 | while (native_apic_mem_read(APIC_ICR) & APIC_ICR_BUSY) | ||
55 | cpu_relax(); | ||
56 | } | ||
57 | |||
58 | static inline void __send_IPI_shortcut(unsigned int shortcut, int vector, | ||
59 | unsigned int dest) | ||
60 | { | ||
61 | /* | ||
62 | * Subtle. In the case of the 'never do double writes' workaround | ||
63 | * we have to lock out interrupts to be safe. As we don't care | ||
64 | * of the value read we use an atomic rmw access to avoid costly | ||
65 | * cli/sti. Otherwise we use an even cheaper single atomic write | ||
66 | * to the APIC. | ||
67 | */ | ||
68 | unsigned int cfg; | ||
69 | |||
70 | /* | ||
71 | * Wait for idle. | ||
72 | */ | ||
73 | __xapic_wait_icr_idle(); | ||
74 | |||
75 | /* | ||
76 | * No need to touch the target chip field | ||
77 | */ | ||
78 | cfg = __prepare_ICR(shortcut, vector, dest); | ||
79 | |||
80 | /* | ||
81 | * Send the IPI. The write to APIC_ICR fires this off. | ||
82 | */ | ||
83 | native_apic_mem_write(APIC_ICR, cfg); | ||
84 | } | ||
85 | |||
86 | /* | ||
87 | * This is used to send an IPI with no shorthand notation (the destination is | ||
88 | * specified in bits 56 to 63 of the ICR). | ||
89 | */ | ||
90 | static inline void __send_IPI_dest_field(unsigned int mask, int vector, | ||
91 | unsigned int dest) | ||
92 | { | ||
93 | unsigned long cfg; | ||
94 | |||
95 | /* | ||
96 | * Wait for idle. | ||
97 | */ | ||
98 | if (unlikely(vector == NMI_VECTOR)) | ||
99 | safe_apic_wait_icr_idle(); | ||
100 | else | ||
101 | __xapic_wait_icr_idle(); | ||
102 | |||
103 | /* | ||
104 | * prepare target chip field | ||
105 | */ | ||
106 | cfg = __prepare_ICR2(mask); | ||
107 | native_apic_mem_write(APIC_ICR2, cfg); | ||
108 | |||
109 | /* | ||
110 | * program the ICR | ||
111 | */ | ||
112 | cfg = __prepare_ICR(0, vector, dest); | ||
113 | |||
114 | /* | ||
115 | * Send the IPI. The write to APIC_ICR fires this off. | ||
116 | */ | ||
117 | native_apic_mem_write(APIC_ICR, cfg); | ||
118 | } | ||
119 | |||
120 | static inline void send_IPI_mask_sequence(cpumask_t mask, int vector) | ||
121 | { | ||
122 | unsigned long flags; | ||
123 | unsigned long query_cpu; | ||
124 | |||
125 | /* | ||
126 | * Hack. The clustered APIC addressing mode doesn't allow us to send | ||
127 | * to an arbitrary mask, so I do a unicast to each CPU instead. | ||
128 | * - mbligh | ||
129 | */ | ||
130 | local_irq_save(flags); | ||
131 | for_each_cpu_mask_nr(query_cpu, mask) { | ||
132 | __send_IPI_dest_field(per_cpu(x86_cpu_to_apicid, query_cpu), | ||
133 | vector, APIC_DEST_PHYSICAL); | ||
134 | } | ||
135 | local_irq_restore(flags); | ||
136 | } | ||
137 | |||
138 | #endif /* _ASM_X86_IPI_H */ | ||