xref: /openbmc/linux/arch/x86/kernel/apic/probe_32.c (revision bc5aa3a0)
1 /*
2  * Default generic APIC driver. This handles up to 8 CPUs.
3  *
4  * Copyright 2003 Andi Kleen, SuSE Labs.
5  * Subject to the GNU Public License, v.2
6  *
7  * Generic x86 APIC driver probe layer.
8  */
9 #include <linux/threads.h>
10 #include <linux/cpumask.h>
11 #include <linux/export.h>
12 #include <linux/string.h>
13 #include <linux/kernel.h>
14 #include <linux/ctype.h>
15 #include <linux/init.h>
16 #include <linux/errno.h>
17 #include <asm/fixmap.h>
18 #include <asm/mpspec.h>
19 #include <asm/apicdef.h>
20 #include <asm/apic.h>
21 #include <asm/setup.h>
22 
23 #include <linux/smp.h>
24 #include <asm/ipi.h>
25 
26 #include <linux/interrupt.h>
27 #include <asm/acpi.h>
28 #include <asm/e820.h>
29 
30 #ifdef CONFIG_HOTPLUG_CPU
31 #define DEFAULT_SEND_IPI	(1)
32 #else
33 #define DEFAULT_SEND_IPI	(0)
34 #endif
35 
36 int no_broadcast = DEFAULT_SEND_IPI;
37 
38 static __init int no_ipi_broadcast(char *str)
39 {
40 	get_option(&str, &no_broadcast);
41 	pr_info("Using %s mode\n",
42 		no_broadcast ? "No IPI Broadcast" : "IPI Broadcast");
43 	return 1;
44 }
45 __setup("no_ipi_broadcast=", no_ipi_broadcast);
46 
47 static int __init print_ipi_mode(void)
48 {
49 	pr_info("Using IPI %s mode\n",
50 		no_broadcast ? "No-Shortcut" : "Shortcut");
51 	return 0;
52 }
53 late_initcall(print_ipi_mode);
54 
55 static int default_x86_32_early_logical_apicid(int cpu)
56 {
57 	return 1 << cpu;
58 }
59 
60 static void setup_apic_flat_routing(void)
61 {
62 #ifdef CONFIG_X86_IO_APIC
63 	printk(KERN_INFO
64 		"Enabling APIC mode:  Flat.  Using %d I/O APICs\n",
65 		nr_ioapics);
66 #endif
67 }
68 
69 /* should be called last. */
70 static int probe_default(void)
71 {
72 	return 1;
73 }
74 
75 static struct apic apic_default = {
76 
77 	.name				= "default",
78 	.probe				= probe_default,
79 	.acpi_madt_oem_check		= NULL,
80 	.apic_id_valid			= default_apic_id_valid,
81 	.apic_id_registered		= default_apic_id_registered,
82 
83 	.irq_delivery_mode		= dest_LowestPrio,
84 	/* logical delivery broadcast to all CPUs: */
85 	.irq_dest_mode			= 1,
86 
87 	.target_cpus			= default_target_cpus,
88 	.disable_esr			= 0,
89 	.dest_logical			= APIC_DEST_LOGICAL,
90 	.check_apicid_used		= default_check_apicid_used,
91 
92 	.vector_allocation_domain	= flat_vector_allocation_domain,
93 	.init_apic_ldr			= default_init_apic_ldr,
94 
95 	.ioapic_phys_id_map		= default_ioapic_phys_id_map,
96 	.setup_apic_routing		= setup_apic_flat_routing,
97 	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
98 	.apicid_to_cpu_present		= physid_set_mask_of_physid,
99 	.check_phys_apicid_present	= default_check_phys_apicid_present,
100 	.phys_pkg_id			= default_phys_pkg_id,
101 
102 	.get_apic_id			= default_get_apic_id,
103 	.set_apic_id			= NULL,
104 
105 	.cpu_mask_to_apicid_and		= flat_cpu_mask_to_apicid_and,
106 
107 	.send_IPI			= default_send_IPI_single,
108 	.send_IPI_mask			= default_send_IPI_mask_logical,
109 	.send_IPI_mask_allbutself	= default_send_IPI_mask_allbutself_logical,
110 	.send_IPI_allbutself		= default_send_IPI_allbutself,
111 	.send_IPI_all			= default_send_IPI_all,
112 	.send_IPI_self			= default_send_IPI_self,
113 
114 	.inquire_remote_apic		= default_inquire_remote_apic,
115 
116 	.read				= native_apic_mem_read,
117 	.write				= native_apic_mem_write,
118 	.eoi_write			= native_apic_mem_write,
119 	.icr_read			= native_apic_icr_read,
120 	.icr_write			= native_apic_icr_write,
121 	.wait_icr_idle			= native_apic_wait_icr_idle,
122 	.safe_wait_icr_idle		= native_safe_apic_wait_icr_idle,
123 
124 	.x86_32_early_logical_apicid	= default_x86_32_early_logical_apicid,
125 };
126 
127 apic_driver(apic_default);
128 
129 struct apic *apic = &apic_default;
130 EXPORT_SYMBOL_GPL(apic);
131 
132 static int cmdline_apic __initdata;
133 static int __init parse_apic(char *arg)
134 {
135 	struct apic **drv;
136 
137 	if (!arg)
138 		return -EINVAL;
139 
140 	for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
141 		if (!strcmp((*drv)->name, arg)) {
142 			apic = *drv;
143 			cmdline_apic = 1;
144 			return 0;
145 		}
146 	}
147 
148 	/* Parsed again by __setup for debug/verbose */
149 	return 0;
150 }
151 early_param("apic", parse_apic);
152 
153 void __init default_setup_apic_routing(void)
154 {
155 	int version = apic_version[boot_cpu_physical_apicid];
156 
157 	if (num_possible_cpus() > 8) {
158 		switch (boot_cpu_data.x86_vendor) {
159 		case X86_VENDOR_INTEL:
160 			if (!APIC_XAPIC(version)) {
161 				def_to_bigsmp = 0;
162 				break;
163 			}
164 			/* If P4 and above fall through */
165 		case X86_VENDOR_AMD:
166 			def_to_bigsmp = 1;
167 		}
168 	}
169 
170 #ifdef CONFIG_X86_BIGSMP
171 	/*
172 	 * This is used to switch to bigsmp mode when
173 	 * - There is no apic= option specified by the user
174 	 * - generic_apic_probe() has chosen apic_default as the sub_arch
175 	 * - we find more than 8 CPUs in acpi LAPIC listing with xAPIC support
176 	 */
177 
178 	if (!cmdline_apic && apic == &apic_default)
179 		generic_bigsmp_probe();
180 #endif
181 
182 	if (apic->setup_apic_routing)
183 		apic->setup_apic_routing();
184 
185 	if (x86_platform.apic_post_init)
186 		x86_platform.apic_post_init();
187 }
188 
189 void __init generic_apic_probe(void)
190 {
191 	if (!cmdline_apic) {
192 		struct apic **drv;
193 
194 		for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
195 			if ((*drv)->probe()) {
196 				apic = *drv;
197 				break;
198 			}
199 		}
200 		/* Not visible without early console */
201 		if (drv == __apicdrivers_end)
202 			panic("Didn't find an APIC driver");
203 	}
204 	printk(KERN_INFO "Using APIC driver %s\n", apic->name);
205 }
206 
207 /* This function can switch the APIC even after the initial ->probe() */
208 int __init default_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
209 {
210 	struct apic **drv;
211 
212 	for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
213 		if (!(*drv)->acpi_madt_oem_check)
214 			continue;
215 		if (!(*drv)->acpi_madt_oem_check(oem_id, oem_table_id))
216 			continue;
217 
218 		if (!cmdline_apic) {
219 			apic = *drv;
220 			printk(KERN_INFO "Switched to APIC driver `%s'.\n",
221 			       apic->name);
222 		}
223 		return 1;
224 	}
225 	return 0;
226 }
227