1 /*
2  * Copyright 2004 James Cleverdon, IBM.
3  * Subject to the GNU Public License, v.2
4  *
5  * Flat APIC subarch code.
6  *
7  * Hacked for x86-64 by James Cleverdon from i386 architecture code by
8  * Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and
9  * James Cleverdon.
10  */
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/hardirq.h>
18 #include <linux/export.h>
19 #include <asm/smp.h>
20 #include <asm/apic.h>
21 #include <asm/ipi.h>
22 
23 #include <linux/acpi.h>
24 
25 static struct apic apic_physflat;
26 static struct apic apic_flat;
27 
28 struct apic __read_mostly *apic = &apic_flat;
29 EXPORT_SYMBOL_GPL(apic);
30 
31 static int flat_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
32 {
33 	return 1;
34 }
35 
36 /*
37  * Set up the logical destination ID.
38  *
39  * Intel recommends to set DFR, LDR and TPR before enabling
40  * an APIC.  See e.g. "AP-388 82489DX User's Manual" (Intel
41  * document number 292116).  So here it goes...
42  */
43 void flat_init_apic_ldr(void)
44 {
45 	unsigned long val;
46 	unsigned long num, id;
47 
48 	num = smp_processor_id();
49 	id = 1UL << num;
50 	apic_write(APIC_DFR, APIC_DFR_FLAT);
51 	val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
52 	val |= SET_APIC_LOGICAL_ID(id);
53 	apic_write(APIC_LDR, val);
54 }
55 
56 static void _flat_send_IPI_mask(unsigned long mask, int vector)
57 {
58 	unsigned long flags;
59 
60 	local_irq_save(flags);
61 	__default_send_IPI_dest_field(mask, vector, apic->dest_logical);
62 	local_irq_restore(flags);
63 }
64 
65 static void flat_send_IPI_mask(const struct cpumask *cpumask, int vector)
66 {
67 	unsigned long mask = cpumask_bits(cpumask)[0];
68 
69 	_flat_send_IPI_mask(mask, vector);
70 }
71 
72 static void
73 flat_send_IPI_mask_allbutself(const struct cpumask *cpumask, int vector)
74 {
75 	unsigned long mask = cpumask_bits(cpumask)[0];
76 	int cpu = smp_processor_id();
77 
78 	if (cpu < BITS_PER_LONG)
79 		clear_bit(cpu, &mask);
80 
81 	_flat_send_IPI_mask(mask, vector);
82 }
83 
84 static void flat_send_IPI_allbutself(int vector)
85 {
86 	int cpu = smp_processor_id();
87 #ifdef	CONFIG_HOTPLUG_CPU
88 	int hotplug = 1;
89 #else
90 	int hotplug = 0;
91 #endif
92 	if (hotplug || vector == NMI_VECTOR) {
93 		if (!cpumask_equal(cpu_online_mask, cpumask_of(cpu))) {
94 			unsigned long mask = cpumask_bits(cpu_online_mask)[0];
95 
96 			if (cpu < BITS_PER_LONG)
97 				clear_bit(cpu, &mask);
98 
99 			_flat_send_IPI_mask(mask, vector);
100 		}
101 	} else if (num_online_cpus() > 1) {
102 		__default_send_IPI_shortcut(APIC_DEST_ALLBUT,
103 					    vector, apic->dest_logical);
104 	}
105 }
106 
107 static void flat_send_IPI_all(int vector)
108 {
109 	if (vector == NMI_VECTOR) {
110 		flat_send_IPI_mask(cpu_online_mask, vector);
111 	} else {
112 		__default_send_IPI_shortcut(APIC_DEST_ALLINC,
113 					    vector, apic->dest_logical);
114 	}
115 }
116 
117 static unsigned int flat_get_apic_id(unsigned long x)
118 {
119 	unsigned int id;
120 
121 	id = (((x)>>24) & 0xFFu);
122 
123 	return id;
124 }
125 
126 static unsigned long set_apic_id(unsigned int id)
127 {
128 	unsigned long x;
129 
130 	x = ((id & 0xFFu)<<24);
131 	return x;
132 }
133 
134 static unsigned int read_xapic_id(void)
135 {
136 	unsigned int id;
137 
138 	id = flat_get_apic_id(apic_read(APIC_ID));
139 	return id;
140 }
141 
142 static int flat_apic_id_registered(void)
143 {
144 	return physid_isset(read_xapic_id(), phys_cpu_present_map);
145 }
146 
147 static int flat_phys_pkg_id(int initial_apic_id, int index_msb)
148 {
149 	return initial_apic_id >> index_msb;
150 }
151 
152 static int flat_probe(void)
153 {
154 	return 1;
155 }
156 
157 static struct apic apic_flat =  {
158 	.name				= "flat",
159 	.probe				= flat_probe,
160 	.acpi_madt_oem_check		= flat_acpi_madt_oem_check,
161 	.apic_id_valid			= default_apic_id_valid,
162 	.apic_id_registered		= flat_apic_id_registered,
163 
164 	.irq_delivery_mode		= dest_LowestPrio,
165 	.irq_dest_mode			= 1, /* logical */
166 
167 	.target_cpus			= online_target_cpus,
168 	.disable_esr			= 0,
169 	.dest_logical			= APIC_DEST_LOGICAL,
170 	.check_apicid_used		= NULL,
171 
172 	.vector_allocation_domain	= flat_vector_allocation_domain,
173 	.init_apic_ldr			= flat_init_apic_ldr,
174 
175 	.ioapic_phys_id_map		= NULL,
176 	.setup_apic_routing		= NULL,
177 	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
178 	.apicid_to_cpu_present		= NULL,
179 	.check_phys_apicid_present	= default_check_phys_apicid_present,
180 	.phys_pkg_id			= flat_phys_pkg_id,
181 
182 	.get_apic_id			= flat_get_apic_id,
183 	.set_apic_id			= set_apic_id,
184 
185 	.cpu_mask_to_apicid_and		= flat_cpu_mask_to_apicid_and,
186 
187 	.send_IPI			= default_send_IPI_single,
188 	.send_IPI_mask			= flat_send_IPI_mask,
189 	.send_IPI_mask_allbutself	= flat_send_IPI_mask_allbutself,
190 	.send_IPI_allbutself		= flat_send_IPI_allbutself,
191 	.send_IPI_all			= flat_send_IPI_all,
192 	.send_IPI_self			= apic_send_IPI_self,
193 
194 	.inquire_remote_apic		= default_inquire_remote_apic,
195 
196 	.read				= native_apic_mem_read,
197 	.write				= native_apic_mem_write,
198 	.eoi_write			= native_apic_mem_write,
199 	.icr_read			= native_apic_icr_read,
200 	.icr_write			= native_apic_icr_write,
201 	.wait_icr_idle			= native_apic_wait_icr_idle,
202 	.safe_wait_icr_idle		= native_safe_apic_wait_icr_idle,
203 };
204 
205 /*
206  * Physflat mode is used when there are more than 8 CPUs on a system.
207  * We cannot use logical delivery in this case because the mask
208  * overflows, so use physical mode.
209  */
210 static int physflat_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
211 {
212 #ifdef CONFIG_ACPI
213 	/*
214 	 * Quirk: some x86_64 machines can only use physical APIC mode
215 	 * regardless of how many processors are present (x86_64 ES7000
216 	 * is an example).
217 	 */
218 	if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
219 		(acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL)) {
220 		printk(KERN_DEBUG "system APIC only can use physical flat");
221 		return 1;
222 	}
223 
224 	if (!strncmp(oem_id, "IBM", 3) && !strncmp(oem_table_id, "EXA", 3)) {
225 		printk(KERN_DEBUG "IBM Summit detected, will use apic physical");
226 		return 1;
227 	}
228 #endif
229 
230 	return 0;
231 }
232 
233 static void physflat_send_IPI_allbutself(int vector)
234 {
235 	default_send_IPI_mask_allbutself_phys(cpu_online_mask, vector);
236 }
237 
238 static void physflat_send_IPI_all(int vector)
239 {
240 	default_send_IPI_mask_sequence_phys(cpu_online_mask, vector);
241 }
242 
243 static int physflat_probe(void)
244 {
245 	if (apic == &apic_physflat || num_possible_cpus() > 8)
246 		return 1;
247 
248 	return 0;
249 }
250 
251 static struct apic apic_physflat =  {
252 
253 	.name				= "physical flat",
254 	.probe				= physflat_probe,
255 	.acpi_madt_oem_check		= physflat_acpi_madt_oem_check,
256 	.apic_id_valid			= default_apic_id_valid,
257 	.apic_id_registered		= flat_apic_id_registered,
258 
259 	.irq_delivery_mode		= dest_Fixed,
260 	.irq_dest_mode			= 0, /* physical */
261 
262 	.target_cpus			= online_target_cpus,
263 	.disable_esr			= 0,
264 	.dest_logical			= 0,
265 	.check_apicid_used		= NULL,
266 
267 	.vector_allocation_domain	= default_vector_allocation_domain,
268 	/* not needed, but shouldn't hurt: */
269 	.init_apic_ldr			= flat_init_apic_ldr,
270 
271 	.ioapic_phys_id_map		= NULL,
272 	.setup_apic_routing		= NULL,
273 	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
274 	.apicid_to_cpu_present		= NULL,
275 	.check_phys_apicid_present	= default_check_phys_apicid_present,
276 	.phys_pkg_id			= flat_phys_pkg_id,
277 
278 	.get_apic_id			= flat_get_apic_id,
279 	.set_apic_id			= set_apic_id,
280 
281 	.cpu_mask_to_apicid_and		= default_cpu_mask_to_apicid_and,
282 
283 	.send_IPI			= default_send_IPI_single_phys,
284 	.send_IPI_mask			= default_send_IPI_mask_sequence_phys,
285 	.send_IPI_mask_allbutself	= default_send_IPI_mask_allbutself_phys,
286 	.send_IPI_allbutself		= physflat_send_IPI_allbutself,
287 	.send_IPI_all			= physflat_send_IPI_all,
288 	.send_IPI_self			= apic_send_IPI_self,
289 
290 	.inquire_remote_apic		= default_inquire_remote_apic,
291 
292 	.read				= native_apic_mem_read,
293 	.write				= native_apic_mem_write,
294 	.eoi_write			= native_apic_mem_write,
295 	.icr_read			= native_apic_icr_read,
296 	.icr_write			= native_apic_icr_write,
297 	.wait_icr_idle			= native_apic_wait_icr_idle,
298 	.safe_wait_icr_idle		= native_safe_apic_wait_icr_idle,
299 };
300 
301 /*
302  * We need to check for physflat first, so this order is important.
303  */
304 apic_drivers(apic_physflat, apic_flat);
305