aboutsummaryrefslogtreecommitdiff
path: root/arch/mips/cavium-octeon/smp.c
blob: c3e2b85c3b0294ef75315e683100c730ace5820a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2004-2008, 2009, 2010 Cavium Networks
 */
#include <linux/cpu.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/smp.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/sched.h>
#include <linux/module.h>

#include <asm/mmu_context.h>
#include <asm/time.h>
#include <asm/setup.h>

#include <asm/octeon/octeon.h>

#include "octeon_boot.h"

volatile unsigned long octeon_processor_boot = 0xff;
volatile unsigned long octeon_processor_sp;
volatile unsigned long octeon_processor_gp;

#ifdef CONFIG_HOTPLUG_CPU
uint64_t octeon_bootloader_entry_addr;
EXPORT_SYMBOL(octeon_bootloader_entry_addr);
#endif

static irqreturn_t mailbox_interrupt(int irq, void *dev_id)
{
	const int coreid = cvmx_get_core_num();
	uint64_t action;

	/* Load the mailbox register to figure out what we're supposed to do */
	action = cvmx_read_csr(CVMX_CIU_MBOX_CLRX(coreid)) & 0xffff;

	/* Clear the mailbox to clear the interrupt */
	cvmx_write_csr(CVMX_CIU_MBOX_CLRX(coreid), action);

	if (action & SMP_CALL_FUNCTION)
		smp_call_function_interrupt();
	if (action & SMP_RESCHEDULE_YOURSELF)
		scheduler_ipi();

	/* Check if we've been told to flush the icache */
	if (action & SMP_ICACHE_FLUSH)
		asm volatile ("synci 0($0)\n");
	return IRQ_HANDLED;
}

/**
 * Cause the function described by call_data to be executed on the passed
 * cpu.  When the function has finished, increment the finished field of
 * call_data.
 */
void octeon_send_ipi_single(int cpu, unsigned int action)
{
	int coreid = cpu_logical_map(cpu);
	/*
	pr_info("SMP: Mailbox send cpu=%d, coreid=%d, action=%u\n", cpu,
	       coreid, action);
	*/
	cvmx_write_csr(CVMX_CIU_MBOX_SETX(coreid), action);
}

static inline void octeon_send_ipi_mask(const struct cpumask *mask,
					unsigned int action)
{
	unsigned int i;

	for_each_cpu_mask(i, *mask)
		octeon_send_ipi_single(i, action);
}

/**
 * Detect available CPUs, populate cpu_possible_map
 */
static void octeon_smp_hotplug_setup(void)
{
#ifdef CONFIG_HOTPLUG_CPU
	struct linux_app_boot_info *labi;

	labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);
	if (labi->labi_signature != LABI_SIGNATURE)
		panic("The bootloader version on this board is incorrect.");

	octeon_bootloader_entry_addr = labi->InitTLBStart_addr;
#endif
}

static void octeon_smp_setup(void)
{
	const int coreid = cvmx_get_core_num();
	int cpus;
	int id;
	int core_mask = octeon_get_boot_coremask();
#ifdef CONFIG_HOTPLUG_CPU
	unsigned int num_cores = cvmx_octeon_num_cores();
#endif

	/* The present CPUs are initially just the boot cpu (CPU 0). */
	for (id = 0; id < NR_CPUS; id++) {
		set_cpu_possible(id, id == 0);
		set_cpu_present(id, id == 0);
	}

	__cpu_number_map[coreid] = 0;
	__cpu_logical_map[0] = coreid;

	/* The present CPUs get the lowest CPU numbers. */
	cpus = 1;
	for (id = 0; id < NR_CPUS; id++) {
		if ((id != coreid) && (core_mask & (1 << id))) {
			set_cpu_possible(cpus, true);
			set_cpu_present(cpus, true);
			__cpu_number_map[id] = cpus;
			__cpu_logical_map[cpus] = id;
			cpus++;
		}
	}

#ifdef CONFIG_HOTPLUG_CPU
	/*
	 * The possible CPUs are all those present on the chip.  We
	 * will assign CPU numbers for possible cores as well.  Cores
	 * are always consecutively numberd from 0.
	 */
	for (id = 0; id < num_cores && id < NR_CPUS; id++) {
		if (!(core_mask & (1 << id))) {
			set_cpu_possible(cpus, true);
			__cpu_number_map[id] = cpus;
			__cpu_logical_map[cpus] = id;
			cpus++;
		}
	}
#endif

	octeon_smp_hotplug_setup();
}

/**
 * Firmware CPU startup hook
 *
 */
static void octeon_boot_secondary(int cpu, struct task_struct *idle)
{
	int count;

	pr_info("SMP: Booting CPU%02d (CoreId %2d)...\n", cpu,
		cpu_logical_map(cpu));

	octeon_processor_sp = __KSTK_TOS(idle);
	octeon_processor_gp = (unsigned long)(task_thread_info(idle));
	octeon_processor_boot = cpu_logical_map(cpu);
	mb();

	count = 10000;
	while (octeon_processor_sp && count) {
		/* Waiting for processor to get the SP and GP */
		udelay(1);
		count--;
	}
	if (count == 0)
		pr_err("Secondary boot timeout\n");
}

/**
 * After we've done initial boot, this function is called to allow the
 * board code to clean up state, if needed
 */
static void __cpuinit octeon_init_secondary(void)
{
	unsigned int sr;

	sr = set_c0_status(ST0_BEV);
	write_c0_ebase((u32)ebase);
	write_c0_status(sr);

	octeon_check_cpu_bist();
	octeon_init_cvmcount();

	octeon_irq_setup_secondary();
	raw_local_irq_enable();
}

/**
 * Callout to firmware before smp_init
 *
 */
void octeon_prepare_cpus(unsigned int max_cpus)
{
#ifdef CONFIG_HOTPLUG_CPU
	struct linux_app_boot_info *labi;

	labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);

	if (labi->labi_signature != LABI_SIGNATURE)
		panic("The bootloader version on this board is incorrect.");
#endif
	/*
	 * Only the low order mailbox bits are used for IPIs, leave
	 * the other bits alone.
	 */
	cvmx_write_csr(CVMX_CIU_MBOX_CLRX(cvmx_get_core_num()), 0xffff);
	if (request_irq(OCTEON_IRQ_MBOX0, mailbox_interrupt,
			IRQF_PERCPU | IRQF_NO_THREAD, "SMP-IPI",
			mailbox_interrupt)) {
		panic("Cannot request_irq(OCTEON_IRQ_MBOX0)");
	}
}

/**
 * Last chance for the board code to finish SMP initialization before
 * the CPU is "online".
 */
static void octeon_smp_finish(void)
{
#ifdef CONFIG_CAVIUM_GDB
	unsigned long tmp;
	/* Pulse MCD0 signal on Ctrl-C to stop all the cores. Also set the MCD0
	   to be not masked by this core so we know the signal is received by
	   someone */
	asm volatile ("dmfc0 %0, $22\n"
		      "ori   %0, %0, 0x9100\n" "dmtc0 %0, $22\n" : "=r" (tmp));
#endif

	octeon_user_io_init();

	/* to generate the first CPU timer interrupt */
	write_c0_compare(read_c0_count() + mips_hpt_frequency / HZ);
}

/**
 * Hook for after all CPUs are online
 */
static void octeon_cpus_done(void)
{
#ifdef CONFIG_CAVIUM_GDB
	unsigned long tmp;
	/* Pulse MCD0 signal on Ctrl-C to stop all the cores. Also set the MCD0
	   to be not masked by this core so we know the signal is received by
	   someone */
	asm volatile ("dmfc0 %0, $22\n"
		      "ori   %0, %0, 0x9100\n" "dmtc0 %0, $22\n" : "=r" (tmp));
#endif
}

#ifdef CONFIG_HOTPLUG_CPU

/* State of each CPU. */
DEFINE_PER_CPU(int, cpu_state);

extern void fixup_irqs(void);

static DEFINE_SPINLOCK(smp_reserve_lock);

static int octeon_cpu_disable(void)
{
	unsigned int cpu = smp_processor_id();

	if (cpu == 0)
		return -EBUSY;

	spin_lock(&smp_reserve_lock);

	cpu_clear(cpu, cpu_online_map);
	cpu_clear(cpu, cpu_callin_map);
	local_irq_disable();
	fixup_irqs();
	local_irq_enable();

	flush_cache_all();
	local_flush_tlb_all();

	spin_unlock(&smp_reserve_lock);

	return 0;
}

static void octeon_cpu_die(unsigned int cpu)
{
	int coreid = cpu_logical_map(cpu);
	uint32_t mask, new_mask;
	const struct cvmx_bootmem_named_block_desc *block_desc;

	while (per_cpu(cpu_state, cpu) != CPU_DEAD)
		cpu_relax();

	/*
	 * This is a bit complicated strategics of getting/settig available
	 * cores mask, copied from bootloader
	 */

	mask = 1 << coreid;
	/* LINUX_APP_BOOT_BLOCK is initialized in bootoct binary */
	block_desc = cvmx_bootmem_find_named_block(LINUX_APP_BOOT_BLOCK_NAME);

	if (!block_desc) {
		struct linux_app_boot_info *labi;

		labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);

		labi->avail_coremask |= mask;
		new_mask = labi->avail_coremask;
	} else {		       /* alternative, already initialized */
		uint32_t *p = (uint32_t *)PHYS_TO_XKSEG_CACHED(block_desc->base_addr +
							       AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK);
		*p |= mask;
		new_mask = *p;
	}

	pr_info("Reset core %d. Available Coremask = 0x%x \n", coreid, new_mask);
	mb();
	cvmx_write_csr(CVMX_CIU_PP_RST, 1 << coreid);
	cvmx_write_csr(CVMX_CIU_PP_RST, 0);
}

void play_dead(void)
{
	int cpu = cpu_number_map(cvmx_get_core_num());

	idle_task_exit();
	octeon_processor_boot = 0xff;
	per_cpu(cpu_state, cpu) = CPU_DEAD;

	mb();

	while (1)	/* core will be reset here */
		;
}

extern void kernel_entry(unsigned long arg1, ...);

static void start_after_reset(void)
{
	kernel_entry(0, 0, 0);  /* set a2 = 0 for secondary core */
}

static int octeon_update_boot_vector(unsigned int cpu)
{

	int coreid = cpu_logical_map(cpu);
	uint32_t avail_coremask;
	const struct cvmx_bootmem_named_block_desc *block_desc;
	struct boot_init_vector *boot_vect =
		(struct boot_init_vector *)PHYS_TO_XKSEG_CACHED(BOOTLOADER_BOOT_VECTOR);

	block_desc = cvmx_bootmem_find_named_block(LINUX_APP_BOOT_BLOCK_NAME);

	if (!block_desc) {
		struct linux_app_boot_info *labi;

		labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);

		avail_coremask = labi->avail_coremask;
		labi->avail_coremask &= ~(1 << coreid);
	} else {		       /* alternative, already initialized */
		avail_coremask = *(uint32_t *)PHYS_TO_XKSEG_CACHED(
			block_desc->base_addr + AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK);
	}

	if (!(avail_coremask & (1 << coreid))) {
		/* core not available, assume, that catched by simple-executive */
		cvmx_write_csr(CVMX_CIU_PP_RST, 1 << coreid);
		cvmx_write_csr(CVMX_CIU_PP_RST, 0);
	}

	boot_vect[coreid].app_start_func_addr =
		(uint32_t) (unsigned long) start_after_reset;
	boot_vect[coreid].code_addr = octeon_bootloader_entry_addr;

	mb();

	cvmx_write_csr(CVMX_CIU_NMI, (1 << coreid) & avail_coremask);

	return 0;
}

static int __cpuinit octeon_cpu_callback(struct notifier_block *nfb,
	unsigned long action, void *hcpu)
{
	unsigned int cpu = (unsigned long)hcpu;

	switch (action) {
	case CPU_UP_PREPARE:
		octeon_update_boot_vector(cpu);
		break;
	case CPU_ONLINE:
		pr_info("Cpu %d online\n", cpu);
		break;
	case CPU_DEAD:
		break;
	}

	return NOTIFY_OK;
}

static int __cpuinit register_cavium_notifier(void)
{
	hotcpu_notifier(octeon_cpu_callback, 0);
	return 0;
}
late_initcall(register_cavium_notifier);

#endif  /* CONFIG_HOTPLUG_CPU */

struct plat_smp_ops octeon_smp_ops = {
	.send_ipi_single	= octeon_send_ipi_single,
	.send_ipi_mask		= octeon_send_ipi_mask,
	.init_secondary		= octeon_init_secondary,
	.smp_finish		= octeon_smp_finish,
	.cpus_done		= octeon_cpus_done,
	.boot_secondary		= octeon_boot_secondary,
	.smp_setup		= octeon_smp_setup,
	.prepare_cpus		= octeon_prepare_cpus,
#ifdef CONFIG_HOTPLUG_CPU
	.cpu_disable		= octeon_cpu_disable,
	.cpu_die		= octeon_cpu_die,
#endif
};