2 * Copyright 2004 James Cleverdon, IBM.
3 * Subject to the GNU Public License, v.2
5 * Flat APIC subarch code.
7 * Hacked for x86-64 by James Cleverdon from i386 architecture code by
8 * Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and
11 #include <linux/threads.h>
12 #include <linux/cpumask.h>
13 #include <linux/string.h>
14 #include <linux/kernel.h>
15 #include <linux/ctype.h>
16 #include <linux/init.h>
20 static cpumask_t flat_target_cpus(void)
22 return cpu_online_map;
25 static cpumask_t flat_vector_allocation_domain(int cpu)
27 /* Careful. Some cpus do not strictly honor the set of cpus
28 * specified in the interrupt destination when using lowest
29 * priority interrupt delivery mode.
31 * In particular there was a hyperthreading cpu observed to
32 * deliver interrupts to the wrong hyperthread when only one
33 * hyperthread was specified in the interrupt desitination.
35 cpumask_t domain = { { [0] = APIC_ALL_CPUS, } };
40 * Set up the logical destination ID.
42 * Intel recommends to set DFR, LDR and TPR before enabling
43 * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
44 * document number 292116). So here it goes...
46 static void flat_init_apic_ldr(void)
49 unsigned long num, id;
51 num = smp_processor_id();
53 x86_cpu_to_log_apicid[num] = id;
54 apic_write(APIC_DFR, APIC_DFR_FLAT);
55 val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
56 val |= SET_APIC_LOGICAL_ID(id);
57 apic_write(APIC_LDR, val);
60 static void flat_send_IPI_mask(cpumask_t cpumask, int vector)
62 unsigned long mask = cpus_addr(cpumask)[0];
66 local_irq_save(flags);
74 * prepare target chip field
76 cfg = __prepare_ICR2(mask);
77 apic_write(APIC_ICR2, cfg);
82 cfg = __prepare_ICR(0, vector, APIC_DEST_LOGICAL);
85 * Send the IPI. The write to APIC_ICR fires this off.
87 apic_write(APIC_ICR, cfg);
88 local_irq_restore(flags);
91 static void flat_send_IPI_allbutself(int vector)
93 #ifdef CONFIG_HOTPLUG_CPU
98 if (hotplug || vector == NMI_VECTOR) {
99 cpumask_t allbutme = cpu_online_map;
101 cpu_clear(smp_processor_id(), allbutme);
103 if (!cpus_empty(allbutme))
104 flat_send_IPI_mask(allbutme, vector);
105 } else if (num_online_cpus() > 1) {
106 __send_IPI_shortcut(APIC_DEST_ALLBUT, vector,APIC_DEST_LOGICAL);
110 static void flat_send_IPI_all(int vector)
112 if (vector == NMI_VECTOR)
113 flat_send_IPI_mask(cpu_online_map, vector);
115 __send_IPI_shortcut(APIC_DEST_ALLINC, vector, APIC_DEST_LOGICAL);
118 static int flat_apic_id_registered(void)
120 return physid_isset(GET_APIC_ID(apic_read(APIC_ID)), phys_cpu_present_map);
123 static unsigned int flat_cpu_mask_to_apicid(cpumask_t cpumask)
125 return cpus_addr(cpumask)[0] & APIC_ALL_CPUS;
128 static unsigned int phys_pkg_id(int index_msb)
130 return hard_smp_processor_id() >> index_msb;
133 struct genapic apic_flat = {
135 .int_delivery_mode = dest_LowestPrio,
136 .int_dest_mode = (APIC_DEST_LOGICAL != 0),
137 .target_cpus = flat_target_cpus,
138 .vector_allocation_domain = flat_vector_allocation_domain,
139 .apic_id_registered = flat_apic_id_registered,
140 .init_apic_ldr = flat_init_apic_ldr,
141 .send_IPI_all = flat_send_IPI_all,
142 .send_IPI_allbutself = flat_send_IPI_allbutself,
143 .send_IPI_mask = flat_send_IPI_mask,
144 .cpu_mask_to_apicid = flat_cpu_mask_to_apicid,
145 .phys_pkg_id = phys_pkg_id,
149 * Physflat mode is used when there are more than 8 CPUs on a AMD system.
150 * We cannot use logical delivery in this case because the mask
151 * overflows, so use physical mode.
154 static cpumask_t physflat_target_cpus(void)
156 return cpu_online_map;
159 static cpumask_t physflat_vector_allocation_domain(int cpu)
161 cpumask_t domain = CPU_MASK_NONE;
162 cpu_set(cpu, domain);
167 static void physflat_send_IPI_mask(cpumask_t cpumask, int vector)
169 send_IPI_mask_sequence(cpumask, vector);
172 static void physflat_send_IPI_allbutself(int vector)
174 cpumask_t allbutme = cpu_online_map;
176 cpu_clear(smp_processor_id(), allbutme);
177 physflat_send_IPI_mask(allbutme, vector);
180 static void physflat_send_IPI_all(int vector)
182 physflat_send_IPI_mask(cpu_online_map, vector);
185 static unsigned int physflat_cpu_mask_to_apicid(cpumask_t cpumask)
190 * We're using fixed IRQ delivery, can only return one phys APIC ID.
191 * May as well be the first.
193 cpu = first_cpu(cpumask);
194 if ((unsigned)cpu < NR_CPUS)
195 return x86_cpu_to_apicid[cpu];
200 struct genapic apic_physflat = {
201 .name = "physical flat",
202 .int_delivery_mode = dest_Fixed,
203 .int_dest_mode = (APIC_DEST_PHYSICAL != 0),
204 .target_cpus = physflat_target_cpus,
205 .vector_allocation_domain = physflat_vector_allocation_domain,
206 .apic_id_registered = flat_apic_id_registered,
207 .init_apic_ldr = flat_init_apic_ldr,/*not needed, but shouldn't hurt*/
208 .send_IPI_all = physflat_send_IPI_all,
209 .send_IPI_allbutself = physflat_send_IPI_allbutself,
210 .send_IPI_mask = physflat_send_IPI_mask,
211 .cpu_mask_to_apicid = physflat_cpu_mask_to_apicid,
212 .phys_pkg_id = phys_pkg_id,