xref: /linux/arch/mips/cavium-octeon/smp.c (revision bcefe12eff5dca6fdfa94ed85e5bee66380d5cd9)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2004-2008 Cavium Networks
7  */
8 #include <linux/cpu.h>
9 #include <linux/init.h>
10 #include <linux/delay.h>
11 #include <linux/smp.h>
12 #include <linux/interrupt.h>
13 #include <linux/kernel_stat.h>
14 #include <linux/sched.h>
15 #include <linux/module.h>
16 
17 #include <asm/mmu_context.h>
18 #include <asm/system.h>
19 #include <asm/time.h>
20 
21 #include <asm/octeon/octeon.h>
22 
23 #include "octeon_boot.h"
24 
25 volatile unsigned long octeon_processor_boot = 0xff;
26 volatile unsigned long octeon_processor_sp;
27 volatile unsigned long octeon_processor_gp;
28 
29 #ifdef CONFIG_HOTPLUG_CPU
30 static unsigned int InitTLBStart_addr;
31 #endif
32 
33 static irqreturn_t mailbox_interrupt(int irq, void *dev_id)
34 {
35 	const int coreid = cvmx_get_core_num();
36 	uint64_t action;
37 
38 	/* Load the mailbox register to figure out what we're supposed to do */
39 	action = cvmx_read_csr(CVMX_CIU_MBOX_CLRX(coreid));
40 
41 	/* Clear the mailbox to clear the interrupt */
42 	cvmx_write_csr(CVMX_CIU_MBOX_CLRX(coreid), action);
43 
44 	if (action & SMP_CALL_FUNCTION)
45 		smp_call_function_interrupt();
46 
47 	/* Check if we've been told to flush the icache */
48 	if (action & SMP_ICACHE_FLUSH)
49 		asm volatile ("synci 0($0)\n");
50 	return IRQ_HANDLED;
51 }
52 
53 /**
54  * Cause the function described by call_data to be executed on the passed
55  * cpu.  When the function has finished, increment the finished field of
56  * call_data.
57  */
58 void octeon_send_ipi_single(int cpu, unsigned int action)
59 {
60 	int coreid = cpu_logical_map(cpu);
61 	/*
62 	pr_info("SMP: Mailbox send cpu=%d, coreid=%d, action=%u\n", cpu,
63 	       coreid, action);
64 	*/
65 	cvmx_write_csr(CVMX_CIU_MBOX_SETX(coreid), action);
66 }
67 
68 static inline void octeon_send_ipi_mask(const struct cpumask *mask,
69 					unsigned int action)
70 {
71 	unsigned int i;
72 
73 	for_each_cpu_mask(i, *mask)
74 		octeon_send_ipi_single(i, action);
75 }
76 
77 /**
78  * Detect available CPUs, populate cpu_possible_map
79  */
80 static void octeon_smp_hotplug_setup(void)
81 {
82 #ifdef CONFIG_HOTPLUG_CPU
83 	uint32_t labi_signature;
84 
85 	labi_signature =
86 		cvmx_read64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
87 					LABI_ADDR_IN_BOOTLOADER +
88 					offsetof(struct linux_app_boot_info,
89 						    labi_signature)));
90 	if (labi_signature != LABI_SIGNATURE)
91 		pr_err("The bootloader version on this board is incorrect\n");
92 	InitTLBStart_addr =
93 		cvmx_read64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
94 				   LABI_ADDR_IN_BOOTLOADER +
95 					   offsetof(struct linux_app_boot_info,
96 						    InitTLBStart_addr)));
97 #endif
98 }
99 
100 static void octeon_smp_setup(void)
101 {
102 	const int coreid = cvmx_get_core_num();
103 	int cpus;
104 	int id;
105 
106 	int core_mask = octeon_get_boot_coremask();
107 
108 	cpus_clear(cpu_possible_map);
109 	__cpu_number_map[coreid] = 0;
110 	__cpu_logical_map[0] = coreid;
111 	cpu_set(0, cpu_possible_map);
112 
113 	cpus = 1;
114 	for (id = 0; id < 16; id++) {
115 		if ((id != coreid) && (core_mask & (1 << id))) {
116 			cpu_set(cpus, cpu_possible_map);
117 			__cpu_number_map[id] = cpus;
118 			__cpu_logical_map[cpus] = id;
119 			cpus++;
120 		}
121 	}
122 	cpu_present_map = cpu_possible_map;
123 
124 	octeon_smp_hotplug_setup();
125 }
126 
127 /**
128  * Firmware CPU startup hook
129  *
130  */
131 static void octeon_boot_secondary(int cpu, struct task_struct *idle)
132 {
133 	int count;
134 
135 	pr_info("SMP: Booting CPU%02d (CoreId %2d)...\n", cpu,
136 		cpu_logical_map(cpu));
137 
138 	octeon_processor_sp = __KSTK_TOS(idle);
139 	octeon_processor_gp = (unsigned long)(task_thread_info(idle));
140 	octeon_processor_boot = cpu_logical_map(cpu);
141 	mb();
142 
143 	count = 10000;
144 	while (octeon_processor_sp && count) {
145 		/* Waiting for processor to get the SP and GP */
146 		udelay(1);
147 		count--;
148 	}
149 	if (count == 0)
150 		pr_err("Secondary boot timeout\n");
151 }
152 
153 /**
154  * After we've done initial boot, this function is called to allow the
155  * board code to clean up state, if needed
156  */
157 static void octeon_init_secondary(void)
158 {
159 	const int coreid = cvmx_get_core_num();
160 	union cvmx_ciu_intx_sum0 interrupt_enable;
161 
162 #ifdef CONFIG_HOTPLUG_CPU
163 	unsigned int cur_exception_base;
164 
165 	cur_exception_base = cvmx_read64_uint32(
166 		CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
167 			     LABI_ADDR_IN_BOOTLOADER +
168 			     offsetof(struct linux_app_boot_info,
169 				      cur_exception_base)));
170 	/* cur_exception_base is incremented in bootloader after setting */
171 	write_c0_ebase((unsigned int)(cur_exception_base - EXCEPTION_BASE_INCR));
172 #endif
173 	octeon_check_cpu_bist();
174 	octeon_init_cvmcount();
175 	/*
176 	pr_info("SMP: CPU%d (CoreId %lu) started\n", cpu, coreid);
177 	*/
178 	/* Enable Mailbox interrupts to this core. These are the only
179 	   interrupts allowed on line 3 */
180 	cvmx_write_csr(CVMX_CIU_MBOX_CLRX(coreid), 0xffffffff);
181 	interrupt_enable.u64 = 0;
182 	interrupt_enable.s.mbox = 0x3;
183 	cvmx_write_csr(CVMX_CIU_INTX_EN0((coreid * 2)), interrupt_enable.u64);
184 	cvmx_write_csr(CVMX_CIU_INTX_EN0((coreid * 2 + 1)), 0);
185 	cvmx_write_csr(CVMX_CIU_INTX_EN1((coreid * 2)), 0);
186 	cvmx_write_csr(CVMX_CIU_INTX_EN1((coreid * 2 + 1)), 0);
187 	/* Enable core interrupt processing for 2,3 and 7 */
188 	set_c0_status(0x8c01);
189 }
190 
191 /**
192  * Callout to firmware before smp_init
193  *
194  */
195 void octeon_prepare_cpus(unsigned int max_cpus)
196 {
197 	cvmx_write_csr(CVMX_CIU_MBOX_CLRX(cvmx_get_core_num()), 0xffffffff);
198 	if (request_irq(OCTEON_IRQ_MBOX0, mailbox_interrupt, IRQF_DISABLED,
199 			"mailbox0", mailbox_interrupt)) {
200 		panic("Cannot request_irq(OCTEON_IRQ_MBOX0)\n");
201 	}
202 	if (request_irq(OCTEON_IRQ_MBOX1, mailbox_interrupt, IRQF_DISABLED,
203 			"mailbox1", mailbox_interrupt)) {
204 		panic("Cannot request_irq(OCTEON_IRQ_MBOX1)\n");
205 	}
206 }
207 
208 /**
209  * Last chance for the board code to finish SMP initialization before
210  * the CPU is "online".
211  */
212 static void octeon_smp_finish(void)
213 {
214 #ifdef CONFIG_CAVIUM_GDB
215 	unsigned long tmp;
216 	/* Pulse MCD0 signal on Ctrl-C to stop all the cores. Also set the MCD0
217 	   to be not masked by this core so we know the signal is received by
218 	   someone */
219 	asm volatile ("dmfc0 %0, $22\n"
220 		      "ori   %0, %0, 0x9100\n" "dmtc0 %0, $22\n" : "=r" (tmp));
221 #endif
222 
223 	octeon_user_io_init();
224 
225 	/* to generate the first CPU timer interrupt */
226 	write_c0_compare(read_c0_count() + mips_hpt_frequency / HZ);
227 }
228 
229 /**
230  * Hook for after all CPUs are online
231  */
232 static void octeon_cpus_done(void)
233 {
234 #ifdef CONFIG_CAVIUM_GDB
235 	unsigned long tmp;
236 	/* Pulse MCD0 signal on Ctrl-C to stop all the cores. Also set the MCD0
237 	   to be not masked by this core so we know the signal is received by
238 	   someone */
239 	asm volatile ("dmfc0 %0, $22\n"
240 		      "ori   %0, %0, 0x9100\n" "dmtc0 %0, $22\n" : "=r" (tmp));
241 #endif
242 }
243 
244 #ifdef CONFIG_HOTPLUG_CPU
245 
246 /* State of each CPU. */
247 DEFINE_PER_CPU(int, cpu_state);
248 
249 extern void fixup_irqs(void);
250 
251 static DEFINE_SPINLOCK(smp_reserve_lock);
252 
253 static int octeon_cpu_disable(void)
254 {
255 	unsigned int cpu = smp_processor_id();
256 
257 	if (cpu == 0)
258 		return -EBUSY;
259 
260 	spin_lock(&smp_reserve_lock);
261 
262 	cpu_clear(cpu, cpu_online_map);
263 	cpu_clear(cpu, cpu_callin_map);
264 	local_irq_disable();
265 	fixup_irqs();
266 	local_irq_enable();
267 
268 	flush_cache_all();
269 	local_flush_tlb_all();
270 
271 	spin_unlock(&smp_reserve_lock);
272 
273 	return 0;
274 }
275 
276 static void octeon_cpu_die(unsigned int cpu)
277 {
278 	int coreid = cpu_logical_map(cpu);
279 	uint32_t avail_coremask;
280 	struct cvmx_bootmem_named_block_desc *block_desc;
281 
282 #ifdef CONFIG_CAVIUM_OCTEON_WATCHDOG
283 	/* Disable the watchdog */
284 	cvmx_ciu_wdogx_t ciu_wdog;
285 	ciu_wdog.u64 = cvmx_read_csr(CVMX_CIU_WDOGX(cpu));
286 	ciu_wdog.s.mode = 0;
287 	cvmx_write_csr(CVMX_CIU_WDOGX(cpu), ciu_wdog.u64);
288 #endif
289 
290 	while (per_cpu(cpu_state, cpu) != CPU_DEAD)
291 		cpu_relax();
292 
293 	/*
294 	 * This is a bit complicated strategics of getting/settig available
295 	 * cores mask, copied from bootloader
296 	 */
297 	/* LINUX_APP_BOOT_BLOCK is initialized in bootoct binary */
298 	block_desc = cvmx_bootmem_find_named_block(LINUX_APP_BOOT_BLOCK_NAME);
299 
300 	if (!block_desc) {
301 		avail_coremask =
302 			cvmx_read64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
303 						   LABI_ADDR_IN_BOOTLOADER +
304 						   offsetof
305 						   (struct linux_app_boot_info,
306 						    avail_coremask)));
307 	} else {		       /* alternative, already initialized */
308 	       avail_coremask =
309 		   cvmx_read64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
310 						   block_desc->base_addr +
311 						  AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK));
312 	}
313 
314 	avail_coremask |= 1 << coreid;
315 
316 	/* Setting avail_coremask for bootoct binary */
317 	if (!block_desc) {
318 		cvmx_write64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
319 						LABI_ADDR_IN_BOOTLOADER +
320 						offsetof(struct linux_app_boot_info,
321 							 avail_coremask)),
322 				   avail_coremask);
323 	} else {
324 		cvmx_write64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
325 						block_desc->base_addr +
326 						AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK),
327 				   avail_coremask);
328 	}
329 
330 	pr_info("Reset core %d. Available Coremask = %x \n", coreid,
331 		avail_coremask);
332 	cvmx_write_csr(CVMX_CIU_PP_RST, 1 << coreid);
333 	cvmx_write_csr(CVMX_CIU_PP_RST, 0);
334 }
335 
336 void play_dead(void)
337 {
338 	int coreid = cvmx_get_core_num();
339 
340 	idle_task_exit();
341 	octeon_processor_boot = 0xff;
342 	per_cpu(cpu_state, coreid) = CPU_DEAD;
343 
344 	while (1)	/* core will be reset here */
345 		;
346 }
347 
348 extern void kernel_entry(unsigned long arg1, ...);
349 
350 static void start_after_reset(void)
351 {
352 	kernel_entry(0, 0, 0);  /* set a2 = 0 for secondary core */
353 }
354 
355 int octeon_update_boot_vector(unsigned int cpu)
356 {
357 
358 	int coreid = cpu_logical_map(cpu);
359 	unsigned int avail_coremask;
360 	struct cvmx_bootmem_named_block_desc *block_desc;
361 	struct boot_init_vector *boot_vect =
362 		(struct boot_init_vector *) cvmx_phys_to_ptr(0x0 +
363 						  BOOTLOADER_BOOT_VECTOR);
364 
365 	block_desc = cvmx_bootmem_find_named_block(LINUX_APP_BOOT_BLOCK_NAME);
366 
367 	if (!block_desc) {
368 		avail_coremask =
369 			cvmx_read64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
370 					   LABI_ADDR_IN_BOOTLOADER +
371 						offsetof(struct linux_app_boot_info,
372 						avail_coremask)));
373 	} else {		       /* alternative, already initialized */
374 	       avail_coremask =
375 		   cvmx_read64_uint32(CVMX_ADD_SEG(CVMX_MIPS_SPACE_XKPHYS,
376 						   block_desc->base_addr +
377 						   AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK));
378 	}
379 
380 	if (!(avail_coremask & (1 << coreid))) {
381 		/* core not available, assume, that catched by simple-executive */
382 		cvmx_write_csr(CVMX_CIU_PP_RST, 1 << coreid);
383 		cvmx_write_csr(CVMX_CIU_PP_RST, 0);
384 	}
385 
386 	boot_vect[coreid].app_start_func_addr =
387 		(uint32_t) (unsigned long) start_after_reset;
388 	boot_vect[coreid].code_addr = InitTLBStart_addr;
389 
390 	CVMX_SYNC;
391 
392 	cvmx_write_csr(CVMX_CIU_NMI, (1 << coreid) & avail_coremask);
393 
394 	return 0;
395 }
396 
397 static int __cpuinit octeon_cpu_callback(struct notifier_block *nfb,
398 	unsigned long action, void *hcpu)
399 {
400 	unsigned int cpu = (unsigned long)hcpu;
401 
402 	switch (action) {
403 	case CPU_UP_PREPARE:
404 		octeon_update_boot_vector(cpu);
405 		break;
406 	case CPU_ONLINE:
407 		pr_info("Cpu %d online\n", cpu);
408 		break;
409 	case CPU_DEAD:
410 		break;
411 	}
412 
413 	return NOTIFY_OK;
414 }
415 
416 static struct notifier_block __cpuinitdata octeon_cpu_notifier = {
417 	.notifier_call = octeon_cpu_callback,
418 };
419 
420 static int __cpuinit register_cavium_notifier(void)
421 {
422 	register_hotcpu_notifier(&octeon_cpu_notifier);
423 
424 	return 0;
425 }
426 
427 late_initcall(register_cavium_notifier);
428 
429 #endif  /* CONFIG_HOTPLUG_CPU */
430 
431 struct plat_smp_ops octeon_smp_ops = {
432 	.send_ipi_single	= octeon_send_ipi_single,
433 	.send_ipi_mask		= octeon_send_ipi_mask,
434 	.init_secondary		= octeon_init_secondary,
435 	.smp_finish		= octeon_smp_finish,
436 	.cpus_done		= octeon_cpus_done,
437 	.boot_secondary		= octeon_boot_secondary,
438 	.smp_setup		= octeon_smp_setup,
439 	.prepare_cpus		= octeon_prepare_cpus,
440 #ifdef CONFIG_HOTPLUG_CPU
441 	.cpu_disable		= octeon_cpu_disable,
442 	.cpu_die		= octeon_cpu_die,
443 #endif
444 };
445