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/errno.h>
12 #include <linux/threads.h>
13 #include <linux/cpumask.h>
14 #include <linux/string.h>
15 #include <linux/kernel.h>
16 #include <linux/ctype.h>
17 #include <linux/init.h>
20 #include <asm/genapic.h>
22 static cpumask_t flat_target_cpus(void)
24 return cpu_online_map;
27 static cpumask_t flat_vector_allocation_domain(int cpu)
29 /* Careful. Some cpus do not strictly honor the set of cpus
30 * specified in the interrupt destination when using lowest
31 * priority interrupt delivery mode.
33 * In particular there was a hyperthreading cpu observed to
34 * deliver interrupts to the wrong hyperthread when only one
35 * hyperthread was specified in the interrupt desitination.
37 cpumask_t domain = { { [0] = APIC_ALL_CPUS, } };
42 * Set up the logical destination ID.
44 * Intel recommends to set DFR, LDR and TPR before enabling
45 * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
46 * document number 292116). So here it goes...
48 static void flat_init_apic_ldr(void)
51 unsigned long num, id;
53 num = smp_processor_id();
55 x86_cpu_to_log_apicid[num] = id;
56 apic_write(APIC_DFR, APIC_DFR_FLAT);
57 val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
58 val |= SET_APIC_LOGICAL_ID(id);
59 apic_write(APIC_LDR, val);
62 static void flat_send_IPI_mask(cpumask_t cpumask, int vector)
64 unsigned long mask = cpus_addr(cpumask)[0];
67 local_irq_save(flags);
68 __send_IPI_dest_field(mask, vector, APIC_DEST_LOGICAL);
69 local_irq_restore(flags);
72 static void flat_send_IPI_allbutself(int vector)
74 #ifdef CONFIG_HOTPLUG_CPU
79 if (hotplug || vector == NMI_VECTOR) {
80 cpumask_t allbutme = cpu_online_map;
82 cpu_clear(smp_processor_id(), allbutme);
84 if (!cpus_empty(allbutme))
85 flat_send_IPI_mask(allbutme, vector);
86 } else if (num_online_cpus() > 1) {
87 __send_IPI_shortcut(APIC_DEST_ALLBUT, vector,APIC_DEST_LOGICAL);
91 static void flat_send_IPI_all(int vector)
93 if (vector == NMI_VECTOR)
94 flat_send_IPI_mask(cpu_online_map, vector);
96 __send_IPI_shortcut(APIC_DEST_ALLINC, vector, APIC_DEST_LOGICAL);
99 static int flat_apic_id_registered(void)
101 return physid_isset(GET_APIC_ID(apic_read(APIC_ID)), phys_cpu_present_map);
104 static unsigned int flat_cpu_mask_to_apicid(cpumask_t cpumask)
106 return cpus_addr(cpumask)[0] & APIC_ALL_CPUS;
109 static unsigned int phys_pkg_id(int index_msb)
111 return hard_smp_processor_id() >> index_msb;
114 struct genapic apic_flat = {
116 .int_delivery_mode = dest_LowestPrio,
117 .int_dest_mode = (APIC_DEST_LOGICAL != 0),
118 .target_cpus = flat_target_cpus,
119 .vector_allocation_domain = flat_vector_allocation_domain,
120 .apic_id_registered = flat_apic_id_registered,
121 .init_apic_ldr = flat_init_apic_ldr,
122 .send_IPI_all = flat_send_IPI_all,
123 .send_IPI_allbutself = flat_send_IPI_allbutself,
124 .send_IPI_mask = flat_send_IPI_mask,
125 .cpu_mask_to_apicid = flat_cpu_mask_to_apicid,
126 .phys_pkg_id = phys_pkg_id,
130 * Physflat mode is used when there are more than 8 CPUs on a AMD system.
131 * We cannot use logical delivery in this case because the mask
132 * overflows, so use physical mode.
135 static cpumask_t physflat_target_cpus(void)
137 return cpu_online_map;
140 static cpumask_t physflat_vector_allocation_domain(int cpu)
142 cpumask_t domain = CPU_MASK_NONE;
143 cpu_set(cpu, domain);
148 static void physflat_send_IPI_mask(cpumask_t cpumask, int vector)
150 send_IPI_mask_sequence(cpumask, vector);
153 static void physflat_send_IPI_allbutself(int vector)
155 cpumask_t allbutme = cpu_online_map;
157 cpu_clear(smp_processor_id(), allbutme);
158 physflat_send_IPI_mask(allbutme, vector);
161 static void physflat_send_IPI_all(int vector)
163 physflat_send_IPI_mask(cpu_online_map, vector);
166 static unsigned int physflat_cpu_mask_to_apicid(cpumask_t cpumask)
171 * We're using fixed IRQ delivery, can only return one phys APIC ID.
172 * May as well be the first.
174 cpu = first_cpu(cpumask);
175 if ((unsigned)cpu < NR_CPUS)
176 return x86_cpu_to_apicid[cpu];
181 struct genapic apic_physflat = {
182 .name = "physical flat",
183 .int_delivery_mode = dest_Fixed,
184 .int_dest_mode = (APIC_DEST_PHYSICAL != 0),
185 .target_cpus = physflat_target_cpus,
186 .vector_allocation_domain = physflat_vector_allocation_domain,
187 .apic_id_registered = flat_apic_id_registered,
188 .init_apic_ldr = flat_init_apic_ldr,/*not needed, but shouldn't hurt*/
189 .send_IPI_all = physflat_send_IPI_all,
190 .send_IPI_allbutself = physflat_send_IPI_allbutself,
191 .send_IPI_mask = physflat_send_IPI_mask,
192 .cpu_mask_to_apicid = physflat_cpu_mask_to_apicid,
193 .phys_pkg_id = phys_pkg_id,