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/init.h>
18 #include <linux/hardirq.h>
19 #include <asm/smp.h>
20 #include <asm/apic.h>
21 #include <asm/ipi.h>
22 
23 #ifdef CONFIG_ACPI
24 #include <acpi/acpi_bus.h>
25 #endif
26 
27 static int flat_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
28 {
29 	return 1;
30 }
31 
32 static const struct cpumask *flat_target_cpus(void)
33 {
34 	return cpu_online_mask;
35 }
36 
37 static void flat_vector_allocation_domain(int cpu, struct cpumask *retmask)
38 {
39 	/* Careful. Some cpus do not strictly honor the set of cpus
40 	 * specified in the interrupt destination when using lowest
41 	 * priority interrupt delivery mode.
42 	 *
43 	 * In particular there was a hyperthreading cpu observed to
44 	 * deliver interrupts to the wrong hyperthread when only one
45 	 * hyperthread was specified in the interrupt desitination.
46 	 */
47 	cpumask_clear(retmask);
48 	cpumask_bits(retmask)[0] = APIC_ALL_CPUS;
49 }
50 
51 /*
52  * Set up the logical destination ID.
53  *
54  * Intel recommends to set DFR, LDR and TPR before enabling
55  * an APIC.  See e.g. "AP-388 82489DX User's Manual" (Intel
56  * document number 292116).  So here it goes...
57  */
58 static void flat_init_apic_ldr(void)
59 {
60 	unsigned long val;
61 	unsigned long num, id;
62 
63 	num = smp_processor_id();
64 	id = 1UL << num;
65 	apic_write(APIC_DFR, APIC_DFR_FLAT);
66 	val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
67 	val |= SET_APIC_LOGICAL_ID(id);
68 	apic_write(APIC_LDR, val);
69 }
70 
71 static inline void _flat_send_IPI_mask(unsigned long mask, int vector)
72 {
73 	unsigned long flags;
74 
75 	local_irq_save(flags);
76 	__default_send_IPI_dest_field(mask, vector, apic->dest_logical);
77 	local_irq_restore(flags);
78 }
79 
80 static void flat_send_IPI_mask(const struct cpumask *cpumask, int vector)
81 {
82 	unsigned long mask = cpumask_bits(cpumask)[0];
83 
84 	_flat_send_IPI_mask(mask, vector);
85 }
86 
87 static void
88  flat_send_IPI_mask_allbutself(const struct cpumask *cpumask, int vector)
89 {
90 	unsigned long mask = cpumask_bits(cpumask)[0];
91 	int cpu = smp_processor_id();
92 
93 	if (cpu < BITS_PER_LONG)
94 		clear_bit(cpu, &mask);
95 
96 	_flat_send_IPI_mask(mask, vector);
97 }
98 
99 static void flat_send_IPI_allbutself(int vector)
100 {
101 	int cpu = smp_processor_id();
102 #ifdef	CONFIG_HOTPLUG_CPU
103 	int hotplug = 1;
104 #else
105 	int hotplug = 0;
106 #endif
107 	if (hotplug || vector == NMI_VECTOR) {
108 		if (!cpumask_equal(cpu_online_mask, cpumask_of(cpu))) {
109 			unsigned long mask = cpumask_bits(cpu_online_mask)[0];
110 
111 			if (cpu < BITS_PER_LONG)
112 				clear_bit(cpu, &mask);
113 
114 			_flat_send_IPI_mask(mask, vector);
115 		}
116 	} else if (num_online_cpus() > 1) {
117 		__default_send_IPI_shortcut(APIC_DEST_ALLBUT,
118 					    vector, apic->dest_logical);
119 	}
120 }
121 
122 static void flat_send_IPI_all(int vector)
123 {
124 	if (vector == NMI_VECTOR) {
125 		flat_send_IPI_mask(cpu_online_mask, vector);
126 	} else {
127 		__default_send_IPI_shortcut(APIC_DEST_ALLINC,
128 					    vector, apic->dest_logical);
129 	}
130 }
131 
132 static unsigned int flat_get_apic_id(unsigned long x)
133 {
134 	unsigned int id;
135 
136 	id = (((x)>>24) & 0xFFu);
137 
138 	return id;
139 }
140 
141 static unsigned long set_apic_id(unsigned int id)
142 {
143 	unsigned long x;
144 
145 	x = ((id & 0xFFu)<<24);
146 	return x;
147 }
148 
149 static unsigned int read_xapic_id(void)
150 {
151 	unsigned int id;
152 
153 	id = flat_get_apic_id(apic_read(APIC_ID));
154 	return id;
155 }
156 
157 static int flat_apic_id_registered(void)
158 {
159 	return physid_isset(read_xapic_id(), phys_cpu_present_map);
160 }
161 
162 static int flat_phys_pkg_id(int initial_apic_id, int index_msb)
163 {
164 	return initial_apic_id >> index_msb;
165 }
166 
167 struct apic apic_flat =  {
168 	.name				= "flat",
169 	.probe				= NULL,
170 	.acpi_madt_oem_check		= flat_acpi_madt_oem_check,
171 	.apic_id_registered		= flat_apic_id_registered,
172 
173 	.irq_delivery_mode		= dest_LowestPrio,
174 	.irq_dest_mode			= 1, /* logical */
175 
176 	.target_cpus			= flat_target_cpus,
177 	.disable_esr			= 0,
178 	.dest_logical			= APIC_DEST_LOGICAL,
179 	.check_apicid_used		= NULL,
180 	.check_apicid_present		= NULL,
181 
182 	.vector_allocation_domain	= flat_vector_allocation_domain,
183 	.init_apic_ldr			= flat_init_apic_ldr,
184 
185 	.ioapic_phys_id_map		= NULL,
186 	.setup_apic_routing		= NULL,
187 	.multi_timer_check		= NULL,
188 	.apicid_to_node			= NULL,
189 	.cpu_to_logical_apicid		= NULL,
190 	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
191 	.apicid_to_cpu_present		= NULL,
192 	.setup_portio_remap		= NULL,
193 	.check_phys_apicid_present	= default_check_phys_apicid_present,
194 	.enable_apic_mode		= NULL,
195 	.phys_pkg_id			= flat_phys_pkg_id,
196 	.mps_oem_check			= NULL,
197 
198 	.get_apic_id			= flat_get_apic_id,
199 	.set_apic_id			= set_apic_id,
200 	.apic_id_mask			= 0xFFu << 24,
201 
202 	.cpu_mask_to_apicid		= default_cpu_mask_to_apicid,
203 	.cpu_mask_to_apicid_and		= default_cpu_mask_to_apicid_and,
204 
205 	.send_IPI_mask			= flat_send_IPI_mask,
206 	.send_IPI_mask_allbutself	= flat_send_IPI_mask_allbutself,
207 	.send_IPI_allbutself		= flat_send_IPI_allbutself,
208 	.send_IPI_all			= flat_send_IPI_all,
209 	.send_IPI_self			= apic_send_IPI_self,
210 
211 	.trampoline_phys_low		= DEFAULT_TRAMPOLINE_PHYS_LOW,
212 	.trampoline_phys_high		= DEFAULT_TRAMPOLINE_PHYS_HIGH,
213 	.wait_for_init_deassert		= NULL,
214 	.smp_callin_clear_local_apic	= NULL,
215 	.inquire_remote_apic		= default_inquire_remote_apic,
216 
217 	.read				= native_apic_mem_read,
218 	.write				= native_apic_mem_write,
219 	.icr_read			= native_apic_icr_read,
220 	.icr_write			= native_apic_icr_write,
221 	.wait_icr_idle			= native_apic_wait_icr_idle,
222 	.safe_wait_icr_idle		= native_safe_apic_wait_icr_idle,
223 };
224 
225 /*
226  * Physflat mode is used when there are more than 8 CPUs on a system.
227  * We cannot use logical delivery in this case because the mask
228  * overflows, so use physical mode.
229  */
230 static int physflat_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
231 {
232 #ifdef CONFIG_ACPI
233 	/*
234 	 * Quirk: some x86_64 machines can only use physical APIC mode
235 	 * regardless of how many processors are present (x86_64 ES7000
236 	 * is an example).
237 	 */
238 	if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
239 		(acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL)) {
240 		printk(KERN_DEBUG "system APIC only can use physical flat");
241 		return 1;
242 	}
243 
244 	if (!strncmp(oem_id, "IBM", 3) && !strncmp(oem_table_id, "EXA", 3)) {
245 		printk(KERN_DEBUG "IBM Summit detected, will use apic physical");
246 		return 1;
247 	}
248 #endif
249 
250 	return 0;
251 }
252 
253 static const struct cpumask *physflat_target_cpus(void)
254 {
255 	return cpu_online_mask;
256 }
257 
258 static void physflat_vector_allocation_domain(int cpu, struct cpumask *retmask)
259 {
260 	cpumask_clear(retmask);
261 	cpumask_set_cpu(cpu, retmask);
262 }
263 
264 static void physflat_send_IPI_mask(const struct cpumask *cpumask, int vector)
265 {
266 	default_send_IPI_mask_sequence_phys(cpumask, vector);
267 }
268 
269 static void physflat_send_IPI_mask_allbutself(const struct cpumask *cpumask,
270 					      int vector)
271 {
272 	default_send_IPI_mask_allbutself_phys(cpumask, vector);
273 }
274 
275 static void physflat_send_IPI_allbutself(int vector)
276 {
277 	default_send_IPI_mask_allbutself_phys(cpu_online_mask, vector);
278 }
279 
280 static void physflat_send_IPI_all(int vector)
281 {
282 	physflat_send_IPI_mask(cpu_online_mask, vector);
283 }
284 
285 static unsigned int physflat_cpu_mask_to_apicid(const struct cpumask *cpumask)
286 {
287 	int cpu;
288 
289 	/*
290 	 * We're using fixed IRQ delivery, can only return one phys APIC ID.
291 	 * May as well be the first.
292 	 */
293 	cpu = cpumask_first(cpumask);
294 	if ((unsigned)cpu < nr_cpu_ids)
295 		return per_cpu(x86_cpu_to_apicid, cpu);
296 	else
297 		return BAD_APICID;
298 }
299 
300 static unsigned int
301 physflat_cpu_mask_to_apicid_and(const struct cpumask *cpumask,
302 				const struct cpumask *andmask)
303 {
304 	int cpu;
305 
306 	/*
307 	 * We're using fixed IRQ delivery, can only return one phys APIC ID.
308 	 * May as well be the first.
309 	 */
310 	for_each_cpu_and(cpu, cpumask, andmask) {
311 		if (cpumask_test_cpu(cpu, cpu_online_mask))
312 			break;
313 	}
314 	return per_cpu(x86_cpu_to_apicid, cpu);
315 }
316 
317 struct apic apic_physflat =  {
318 
319 	.name				= "physical flat",
320 	.probe				= NULL,
321 	.acpi_madt_oem_check		= physflat_acpi_madt_oem_check,
322 	.apic_id_registered		= flat_apic_id_registered,
323 
324 	.irq_delivery_mode		= dest_Fixed,
325 	.irq_dest_mode			= 0, /* physical */
326 
327 	.target_cpus			= physflat_target_cpus,
328 	.disable_esr			= 0,
329 	.dest_logical			= 0,
330 	.check_apicid_used		= NULL,
331 	.check_apicid_present		= NULL,
332 
333 	.vector_allocation_domain	= physflat_vector_allocation_domain,
334 	/* not needed, but shouldn't hurt: */
335 	.init_apic_ldr			= flat_init_apic_ldr,
336 
337 	.ioapic_phys_id_map		= NULL,
338 	.setup_apic_routing		= NULL,
339 	.multi_timer_check		= NULL,
340 	.apicid_to_node			= NULL,
341 	.cpu_to_logical_apicid		= NULL,
342 	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
343 	.apicid_to_cpu_present		= NULL,
344 	.setup_portio_remap		= NULL,
345 	.check_phys_apicid_present	= default_check_phys_apicid_present,
346 	.enable_apic_mode		= NULL,
347 	.phys_pkg_id			= flat_phys_pkg_id,
348 	.mps_oem_check			= NULL,
349 
350 	.get_apic_id			= flat_get_apic_id,
351 	.set_apic_id			= set_apic_id,
352 	.apic_id_mask			= 0xFFu << 24,
353 
354 	.cpu_mask_to_apicid		= physflat_cpu_mask_to_apicid,
355 	.cpu_mask_to_apicid_and		= physflat_cpu_mask_to_apicid_and,
356 
357 	.send_IPI_mask			= physflat_send_IPI_mask,
358 	.send_IPI_mask_allbutself	= physflat_send_IPI_mask_allbutself,
359 	.send_IPI_allbutself		= physflat_send_IPI_allbutself,
360 	.send_IPI_all			= physflat_send_IPI_all,
361 	.send_IPI_self			= apic_send_IPI_self,
362 
363 	.trampoline_phys_low		= DEFAULT_TRAMPOLINE_PHYS_LOW,
364 	.trampoline_phys_high		= DEFAULT_TRAMPOLINE_PHYS_HIGH,
365 	.wait_for_init_deassert		= NULL,
366 	.smp_callin_clear_local_apic	= NULL,
367 	.inquire_remote_apic		= default_inquire_remote_apic,
368 
369 	.read				= native_apic_mem_read,
370 	.write				= native_apic_mem_write,
371 	.icr_read			= native_apic_icr_read,
372 	.icr_write			= native_apic_icr_write,
373 	.wait_icr_idle			= native_apic_wait_icr_idle,
374 	.safe_wait_icr_idle		= native_safe_apic_wait_icr_idle,
375 };
376