1 /*
2 * NOOP APIC driver.
3 *
4 * Does almost nothing and should be substituted by a real apic driver via
5 * probe routine.
6 *
7 * Though in case if apic is disabled (for some reason) we try
8 * to not uglify the caller's code and allow to call (some) apic routines
9 * like self-ipi, etc...
10 */
11
12 #include <linux/threads.h>
13 #include <linux/cpumask.h>
14 #include <linux/module.h>
15 #include <linux/string.h>
16 #include <linux/kernel.h>
17 #include <linux/ctype.h>
18 #include <linux/init.h>
19 #include <linux/errno.h>
20 #include <asm/fixmap.h>
21 #include <asm/mpspec.h>
22 #include <asm/apicdef.h>
23 #include <asm/apic.h>
24 #include <asm/setup.h>
25
26 #include <linux/smp.h>
27 #include <asm/ipi.h>
28
29 #include <linux/interrupt.h>
30 #include <asm/acpi.h>
31 #include <asm/e820.h>
32
noop_init_apic_ldr(void)33 static void noop_init_apic_ldr(void) { }
noop_send_IPI_mask(const struct cpumask * cpumask,int vector)34 static void noop_send_IPI_mask(const struct cpumask *cpumask, int vector) { }
noop_send_IPI_mask_allbutself(const struct cpumask * cpumask,int vector)35 static void noop_send_IPI_mask_allbutself(const struct cpumask *cpumask, int vector) { }
noop_send_IPI_allbutself(int vector)36 static void noop_send_IPI_allbutself(int vector) { }
noop_send_IPI_all(int vector)37 static void noop_send_IPI_all(int vector) { }
noop_send_IPI_self(int vector)38 static void noop_send_IPI_self(int vector) { }
noop_apic_wait_icr_idle(void)39 static void noop_apic_wait_icr_idle(void) { }
noop_apic_icr_write(u32 low,u32 id)40 static void noop_apic_icr_write(u32 low, u32 id) { }
41
noop_wakeup_secondary_cpu(int apicid,unsigned long start_eip)42 static int noop_wakeup_secondary_cpu(int apicid, unsigned long start_eip)
43 {
44 return -1;
45 }
46
noop_safe_apic_wait_icr_idle(void)47 static u32 noop_safe_apic_wait_icr_idle(void)
48 {
49 return 0;
50 }
51
noop_apic_icr_read(void)52 static u64 noop_apic_icr_read(void)
53 {
54 return 0;
55 }
56
noop_phys_pkg_id(int cpuid_apic,int index_msb)57 static int noop_phys_pkg_id(int cpuid_apic, int index_msb)
58 {
59 return 0;
60 }
61
noop_get_apic_id(unsigned long x)62 static unsigned int noop_get_apic_id(unsigned long x)
63 {
64 return 0;
65 }
66
noop_probe(void)67 static int noop_probe(void)
68 {
69 /*
70 * NOOP apic should not ever be
71 * enabled via probe routine
72 */
73 return 0;
74 }
75
noop_apic_id_registered(void)76 static int noop_apic_id_registered(void)
77 {
78 /*
79 * if we would be really "pedantic"
80 * we should pass read_apic_id() here
81 * but since NOOP suppose APIC ID = 0
82 * lets save a few cycles
83 */
84 return physid_isset(0, phys_cpu_present_map);
85 }
86
noop_target_cpus(void)87 static const struct cpumask *noop_target_cpus(void)
88 {
89 /* only BSP here */
90 return cpumask_of(0);
91 }
92
noop_check_apicid_used(physid_mask_t * map,int apicid)93 static unsigned long noop_check_apicid_used(physid_mask_t *map, int apicid)
94 {
95 return physid_isset(apicid, *map);
96 }
97
noop_check_apicid_present(int bit)98 static unsigned long noop_check_apicid_present(int bit)
99 {
100 return physid_isset(bit, phys_cpu_present_map);
101 }
102
noop_vector_allocation_domain(int cpu,struct cpumask * retmask)103 static void noop_vector_allocation_domain(int cpu, struct cpumask *retmask)
104 {
105 if (cpu != 0)
106 pr_warning("APIC: Vector allocated for non-BSP cpu\n");
107 cpumask_clear(retmask);
108 cpumask_set_cpu(cpu, retmask);
109 }
110
noop_apic_read(u32 reg)111 static u32 noop_apic_read(u32 reg)
112 {
113 WARN_ON_ONCE((cpu_has_apic && !disable_apic));
114 return 0;
115 }
116
noop_apic_write(u32 reg,u32 v)117 static void noop_apic_write(u32 reg, u32 v)
118 {
119 WARN_ON_ONCE(cpu_has_apic && !disable_apic);
120 }
121
122 struct apic apic_noop = {
123 .name = "noop",
124 .probe = noop_probe,
125 .acpi_madt_oem_check = NULL,
126
127 .apic_id_valid = default_apic_id_valid,
128 .apic_id_registered = noop_apic_id_registered,
129
130 .irq_delivery_mode = dest_LowestPrio,
131 /* logical delivery broadcast to all CPUs: */
132 .irq_dest_mode = 1,
133
134 .target_cpus = noop_target_cpus,
135 .disable_esr = 0,
136 .dest_logical = APIC_DEST_LOGICAL,
137 .check_apicid_used = noop_check_apicid_used,
138 .check_apicid_present = noop_check_apicid_present,
139
140 .vector_allocation_domain = noop_vector_allocation_domain,
141 .init_apic_ldr = noop_init_apic_ldr,
142
143 .ioapic_phys_id_map = default_ioapic_phys_id_map,
144 .setup_apic_routing = NULL,
145 .multi_timer_check = NULL,
146
147 .cpu_present_to_apicid = default_cpu_present_to_apicid,
148 .apicid_to_cpu_present = physid_set_mask_of_physid,
149
150 .setup_portio_remap = NULL,
151 .check_phys_apicid_present = default_check_phys_apicid_present,
152 .enable_apic_mode = NULL,
153
154 .phys_pkg_id = noop_phys_pkg_id,
155
156 .mps_oem_check = NULL,
157
158 .get_apic_id = noop_get_apic_id,
159 .set_apic_id = NULL,
160 .apic_id_mask = 0x0F << 24,
161
162 .cpu_mask_to_apicid = default_cpu_mask_to_apicid,
163 .cpu_mask_to_apicid_and = default_cpu_mask_to_apicid_and,
164
165 .send_IPI_mask = noop_send_IPI_mask,
166 .send_IPI_mask_allbutself = noop_send_IPI_mask_allbutself,
167 .send_IPI_allbutself = noop_send_IPI_allbutself,
168 .send_IPI_all = noop_send_IPI_all,
169 .send_IPI_self = noop_send_IPI_self,
170
171 .wakeup_secondary_cpu = noop_wakeup_secondary_cpu,
172
173 /* should be safe */
174 .trampoline_phys_low = DEFAULT_TRAMPOLINE_PHYS_LOW,
175 .trampoline_phys_high = DEFAULT_TRAMPOLINE_PHYS_HIGH,
176
177 .wait_for_init_deassert = NULL,
178
179 .smp_callin_clear_local_apic = NULL,
180 .inquire_remote_apic = NULL,
181
182 .read = noop_apic_read,
183 .write = noop_apic_write,
184 .icr_read = noop_apic_icr_read,
185 .icr_write = noop_apic_icr_write,
186 .wait_icr_idle = noop_apic_wait_icr_idle,
187 .safe_wait_icr_idle = noop_safe_apic_wait_icr_idle,
188
189 #ifdef CONFIG_X86_32
190 .x86_32_early_logical_apicid = noop_x86_32_early_logical_apicid,
191 #endif
192 };
193