1 #include <linux/threads.h>
2 #include <linux/cpumask.h>
3 #include <linux/string.h>
4 #include <linux/kernel.h>
5 #include <linux/ctype.h>
6 #include <linux/dmar.h>
10 #include <asm/x2apic.h>
12 static DEFINE_PER_CPU(u32
, x86_cpu_to_logical_apicid
);
13 static DEFINE_PER_CPU(cpumask_var_t
, cpus_in_cluster
);
14 static DEFINE_PER_CPU(cpumask_var_t
, ipi_mask
);
16 static int x2apic_acpi_madt_oem_check(char *oem_id
, char *oem_table_id
)
18 return x2apic_enabled();
21 static inline u32
x2apic_cluster(int cpu
)
23 return per_cpu(x86_cpu_to_logical_apicid
, cpu
) >> 16;
26 static void x2apic_send_IPI(int cpu
, int vector
)
28 u32 dest
= per_cpu(x86_cpu_to_logical_apicid
, cpu
);
31 __x2apic_send_IPI_dest(dest
, vector
, APIC_DEST_LOGICAL
);
35 __x2apic_send_IPI_mask(const struct cpumask
*mask
, int vector
, int apic_dest
)
37 struct cpumask
*cpus_in_cluster_ptr
;
38 struct cpumask
*ipi_mask_ptr
;
39 unsigned int cpu
, this_cpu
;
45 local_irq_save(flags
);
47 this_cpu
= smp_processor_id();
50 * We are to modify mask, so we need an own copy
51 * and be sure it's manipulated with irq off.
53 ipi_mask_ptr
= this_cpu_cpumask_var_ptr(ipi_mask
);
54 cpumask_copy(ipi_mask_ptr
, mask
);
57 * The idea is to send one IPI per cluster.
59 for_each_cpu(cpu
, ipi_mask_ptr
) {
62 cpus_in_cluster_ptr
= per_cpu(cpus_in_cluster
, cpu
);
65 /* Collect cpus in cluster. */
66 for_each_cpu_and(i
, ipi_mask_ptr
, cpus_in_cluster_ptr
) {
67 if (apic_dest
== APIC_DEST_ALLINC
|| i
!= this_cpu
)
68 dest
|= per_cpu(x86_cpu_to_logical_apicid
, i
);
74 __x2apic_send_IPI_dest(dest
, vector
, apic
->dest_logical
);
76 * Cluster sibling cpus should be discared now so
77 * we would not send IPI them second time.
79 cpumask_andnot(ipi_mask_ptr
, ipi_mask_ptr
, cpus_in_cluster_ptr
);
82 local_irq_restore(flags
);
85 static void x2apic_send_IPI_mask(const struct cpumask
*mask
, int vector
)
87 __x2apic_send_IPI_mask(mask
, vector
, APIC_DEST_ALLINC
);
91 x2apic_send_IPI_mask_allbutself(const struct cpumask
*mask
, int vector
)
93 __x2apic_send_IPI_mask(mask
, vector
, APIC_DEST_ALLBUT
);
96 static void x2apic_send_IPI_allbutself(int vector
)
98 __x2apic_send_IPI_mask(cpu_online_mask
, vector
, APIC_DEST_ALLBUT
);
101 static void x2apic_send_IPI_all(int vector
)
103 __x2apic_send_IPI_mask(cpu_online_mask
, vector
, APIC_DEST_ALLINC
);
107 x2apic_cpu_mask_to_apicid_and(const struct cpumask
*cpumask
,
108 const struct cpumask
*andmask
,
109 unsigned int *apicid
)
115 for_each_cpu_and(i
, cpumask
, andmask
) {
116 if (!cpumask_test_cpu(i
, cpu_online_mask
))
118 dest
= per_cpu(x86_cpu_to_logical_apicid
, i
);
119 cluster
= x2apic_cluster(i
);
126 for_each_cpu_and(i
, cpumask
, andmask
) {
127 if (!cpumask_test_cpu(i
, cpu_online_mask
))
129 if (cluster
!= x2apic_cluster(i
))
131 dest
|= per_cpu(x86_cpu_to_logical_apicid
, i
);
139 static void init_x2apic_ldr(void)
141 unsigned int this_cpu
= smp_processor_id();
144 per_cpu(x86_cpu_to_logical_apicid
, this_cpu
) = apic_read(APIC_LDR
);
146 cpumask_set_cpu(this_cpu
, per_cpu(cpus_in_cluster
, this_cpu
));
147 for_each_online_cpu(cpu
) {
148 if (x2apic_cluster(this_cpu
) != x2apic_cluster(cpu
))
150 cpumask_set_cpu(this_cpu
, per_cpu(cpus_in_cluster
, cpu
));
151 cpumask_set_cpu(cpu
, per_cpu(cpus_in_cluster
, this_cpu
));
156 * At CPU state changes, update the x2apic cluster sibling info.
158 static int x2apic_prepare_cpu(unsigned int cpu
)
160 if (!zalloc_cpumask_var(&per_cpu(cpus_in_cluster
, cpu
), GFP_KERNEL
))
163 if (!zalloc_cpumask_var(&per_cpu(ipi_mask
, cpu
), GFP_KERNEL
)) {
164 free_cpumask_var(per_cpu(cpus_in_cluster
, cpu
));
171 static int x2apic_dead_cpu(unsigned int this_cpu
)
175 for_each_online_cpu(cpu
) {
176 if (x2apic_cluster(this_cpu
) != x2apic_cluster(cpu
))
178 cpumask_clear_cpu(this_cpu
, per_cpu(cpus_in_cluster
, cpu
));
179 cpumask_clear_cpu(cpu
, per_cpu(cpus_in_cluster
, this_cpu
));
181 free_cpumask_var(per_cpu(cpus_in_cluster
, this_cpu
));
182 free_cpumask_var(per_cpu(ipi_mask
, this_cpu
));
186 static int x2apic_cluster_probe(void)
188 int cpu
= smp_processor_id();
194 ret
= cpuhp_setup_state(CPUHP_X2APIC_PREPARE
, "X2APIC_PREPARE",
195 x2apic_prepare_cpu
, x2apic_dead_cpu
);
197 pr_err("Failed to register X2APIC_PREPARE\n");
200 cpumask_set_cpu(cpu
, per_cpu(cpus_in_cluster
, cpu
));
204 static const struct cpumask
*x2apic_cluster_target_cpus(void)
210 * Each x2apic cluster is an allocation domain.
212 static void cluster_vector_allocation_domain(int cpu
, struct cpumask
*retmask
,
213 const struct cpumask
*mask
)
216 * To minimize vector pressure, default case of boot, device bringup
217 * etc will use a single cpu for the interrupt destination.
219 * On explicit migration requests coming from irqbalance etc,
220 * interrupts will be routed to the x2apic cluster (cluster-id
221 * derived from the first cpu in the mask) members specified
224 if (mask
== x2apic_cluster_target_cpus())
225 cpumask_copy(retmask
, cpumask_of(cpu
));
227 cpumask_and(retmask
, mask
, per_cpu(cpus_in_cluster
, cpu
));
230 static struct apic apic_x2apic_cluster
= {
232 .name
= "cluster x2apic",
233 .probe
= x2apic_cluster_probe
,
234 .acpi_madt_oem_check
= x2apic_acpi_madt_oem_check
,
235 .apic_id_valid
= x2apic_apic_id_valid
,
236 .apic_id_registered
= x2apic_apic_id_registered
,
238 .irq_delivery_mode
= dest_LowestPrio
,
239 .irq_dest_mode
= 1, /* logical */
241 .target_cpus
= x2apic_cluster_target_cpus
,
243 .dest_logical
= APIC_DEST_LOGICAL
,
244 .check_apicid_used
= NULL
,
246 .vector_allocation_domain
= cluster_vector_allocation_domain
,
247 .init_apic_ldr
= init_x2apic_ldr
,
249 .ioapic_phys_id_map
= NULL
,
250 .setup_apic_routing
= NULL
,
251 .cpu_present_to_apicid
= default_cpu_present_to_apicid
,
252 .apicid_to_cpu_present
= NULL
,
253 .check_phys_apicid_present
= default_check_phys_apicid_present
,
254 .phys_pkg_id
= x2apic_phys_pkg_id
,
256 .get_apic_id
= x2apic_get_apic_id
,
257 .set_apic_id
= x2apic_set_apic_id
,
259 .cpu_mask_to_apicid_and
= x2apic_cpu_mask_to_apicid_and
,
261 .send_IPI
= x2apic_send_IPI
,
262 .send_IPI_mask
= x2apic_send_IPI_mask
,
263 .send_IPI_mask_allbutself
= x2apic_send_IPI_mask_allbutself
,
264 .send_IPI_allbutself
= x2apic_send_IPI_allbutself
,
265 .send_IPI_all
= x2apic_send_IPI_all
,
266 .send_IPI_self
= x2apic_send_IPI_self
,
268 .inquire_remote_apic
= NULL
,
270 .read
= native_apic_msr_read
,
271 .write
= native_apic_msr_write
,
272 .eoi_write
= native_apic_msr_eoi_write
,
273 .icr_read
= native_x2apic_icr_read
,
274 .icr_write
= native_x2apic_icr_write
,
275 .wait_icr_idle
= native_x2apic_wait_icr_idle
,
276 .safe_wait_icr_idle
= native_safe_x2apic_wait_icr_idle
,
279 apic_driver(apic_x2apic_cluster
);