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, 2009, 2010 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 uint64_t octeon_bootloader_entry_addr;
31 EXPORT_SYMBOL(octeon_bootloader_entry_addr);
32 #endif
33 
mailbox_interrupt(int irq,void * dev_id)34 static irqreturn_t mailbox_interrupt(int irq, void *dev_id)
35 {
36 	const int coreid = cvmx_get_core_num();
37 	uint64_t action;
38 
39 	/* Load the mailbox register to figure out what we're supposed to do */
40 	action = cvmx_read_csr(CVMX_CIU_MBOX_CLRX(coreid));
41 
42 	/* Clear the mailbox to clear the interrupt */
43 	cvmx_write_csr(CVMX_CIU_MBOX_CLRX(coreid), action);
44 
45 	if (action & SMP_CALL_FUNCTION)
46 		smp_call_function_interrupt();
47 
48 	/* Check if we've been told to flush the icache */
49 	if (action & SMP_ICACHE_FLUSH)
50 		asm volatile ("synci 0($0)\n");
51 	return IRQ_HANDLED;
52 }
53 
54 /**
55  * Cause the function described by call_data to be executed on the passed
56  * cpu.  When the function has finished, increment the finished field of
57  * call_data.
58  */
octeon_send_ipi_single(int cpu,unsigned int action)59 void octeon_send_ipi_single(int cpu, unsigned int action)
60 {
61 	int coreid = cpu_logical_map(cpu);
62 	/*
63 	pr_info("SMP: Mailbox send cpu=%d, coreid=%d, action=%u\n", cpu,
64 	       coreid, action);
65 	*/
66 	cvmx_write_csr(CVMX_CIU_MBOX_SETX(coreid), action);
67 }
68 
octeon_send_ipi_mask(const struct cpumask * mask,unsigned int action)69 static inline void octeon_send_ipi_mask(const struct cpumask *mask,
70 					unsigned int action)
71 {
72 	unsigned int i;
73 
74 	for_each_cpu_mask(i, *mask)
75 		octeon_send_ipi_single(i, action);
76 }
77 
78 /**
79  * Detect available CPUs, populate cpu_possible_map
80  */
octeon_smp_hotplug_setup(void)81 static void octeon_smp_hotplug_setup(void)
82 {
83 #ifdef CONFIG_HOTPLUG_CPU
84 	struct linux_app_boot_info *labi;
85 
86 	labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);
87 	if (labi->labi_signature != LABI_SIGNATURE)
88 		panic("The bootloader version on this board is incorrect.");
89 
90 	octeon_bootloader_entry_addr = labi->InitTLBStart_addr;
91 #endif
92 }
93 
octeon_smp_setup(void)94 static void octeon_smp_setup(void)
95 {
96 	const int coreid = cvmx_get_core_num();
97 	int cpus;
98 	int id;
99 	int core_mask = octeon_get_boot_coremask();
100 #ifdef CONFIG_HOTPLUG_CPU
101 	unsigned int num_cores = cvmx_octeon_num_cores();
102 #endif
103 
104 	/* The present CPUs are initially just the boot cpu (CPU 0). */
105 	for (id = 0; id < NR_CPUS; id++) {
106 		set_cpu_possible(id, id == 0);
107 		set_cpu_present(id, id == 0);
108 	}
109 
110 	__cpu_number_map[coreid] = 0;
111 	__cpu_logical_map[0] = coreid;
112 
113 	/* The present CPUs get the lowest CPU numbers. */
114 	cpus = 1;
115 	for (id = 0; id < NR_CPUS; id++) {
116 		if ((id != coreid) && (core_mask & (1 << id))) {
117 			set_cpu_possible(cpus, true);
118 			set_cpu_present(cpus, true);
119 			__cpu_number_map[id] = cpus;
120 			__cpu_logical_map[cpus] = id;
121 			cpus++;
122 		}
123 	}
124 
125 #ifdef CONFIG_HOTPLUG_CPU
126 	/*
127 	 * The possible CPUs are all those present on the chip.  We
128 	 * will assign CPU numbers for possible cores as well.  Cores
129 	 * are always consecutively numberd from 0.
130 	 */
131 	for (id = 0; id < num_cores && id < NR_CPUS; id++) {
132 		if (!(core_mask & (1 << id))) {
133 			set_cpu_possible(cpus, true);
134 			__cpu_number_map[id] = cpus;
135 			__cpu_logical_map[cpus] = id;
136 			cpus++;
137 		}
138 	}
139 #endif
140 
141 	octeon_smp_hotplug_setup();
142 }
143 
144 /**
145  * Firmware CPU startup hook
146  *
147  */
octeon_boot_secondary(int cpu,struct task_struct * idle)148 static void octeon_boot_secondary(int cpu, struct task_struct *idle)
149 {
150 	int count;
151 
152 	pr_info("SMP: Booting CPU%02d (CoreId %2d)...\n", cpu,
153 		cpu_logical_map(cpu));
154 
155 	octeon_processor_sp = __KSTK_TOS(idle);
156 	octeon_processor_gp = (unsigned long)(task_thread_info(idle));
157 	octeon_processor_boot = cpu_logical_map(cpu);
158 	mb();
159 
160 	count = 10000;
161 	while (octeon_processor_sp && count) {
162 		/* Waiting for processor to get the SP and GP */
163 		udelay(1);
164 		count--;
165 	}
166 	if (count == 0)
167 		pr_err("Secondary boot timeout\n");
168 }
169 
170 /**
171  * After we've done initial boot, this function is called to allow the
172  * board code to clean up state, if needed
173  */
octeon_init_secondary(void)174 static void __cpuinit octeon_init_secondary(void)
175 {
176 	unsigned int sr;
177 
178 	sr = set_c0_status(ST0_BEV);
179 	write_c0_ebase((u32)ebase);
180 	write_c0_status(sr);
181 
182 	octeon_check_cpu_bist();
183 	octeon_init_cvmcount();
184 
185 	octeon_irq_setup_secondary();
186 	raw_local_irq_enable();
187 }
188 
189 /**
190  * Callout to firmware before smp_init
191  *
192  */
octeon_prepare_cpus(unsigned int max_cpus)193 void octeon_prepare_cpus(unsigned int max_cpus)
194 {
195 #ifdef CONFIG_HOTPLUG_CPU
196 	struct linux_app_boot_info *labi;
197 
198 	labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);
199 
200 	if (labi->labi_signature != LABI_SIGNATURE)
201 		panic("The bootloader version on this board is incorrect.");
202 #endif
203 
204 	cvmx_write_csr(CVMX_CIU_MBOX_CLRX(cvmx_get_core_num()), 0xffffffff);
205 	if (request_irq(OCTEON_IRQ_MBOX0, mailbox_interrupt, IRQF_DISABLED,
206 			"mailbox0", mailbox_interrupt)) {
207 		panic("Cannot request_irq(OCTEON_IRQ_MBOX0)\n");
208 	}
209 	if (request_irq(OCTEON_IRQ_MBOX1, mailbox_interrupt, IRQF_DISABLED,
210 			"mailbox1", mailbox_interrupt)) {
211 		panic("Cannot request_irq(OCTEON_IRQ_MBOX1)\n");
212 	}
213 }
214 
215 /**
216  * Last chance for the board code to finish SMP initialization before
217  * the CPU is "online".
218  */
octeon_smp_finish(void)219 static void octeon_smp_finish(void)
220 {
221 #ifdef CONFIG_CAVIUM_GDB
222 	unsigned long tmp;
223 	/* Pulse MCD0 signal on Ctrl-C to stop all the cores. Also set the MCD0
224 	   to be not masked by this core so we know the signal is received by
225 	   someone */
226 	asm volatile ("dmfc0 %0, $22\n"
227 		      "ori   %0, %0, 0x9100\n" "dmtc0 %0, $22\n" : "=r" (tmp));
228 #endif
229 
230 	octeon_user_io_init();
231 
232 	/* to generate the first CPU timer interrupt */
233 	write_c0_compare(read_c0_count() + mips_hpt_frequency / HZ);
234 }
235 
236 /**
237  * Hook for after all CPUs are online
238  */
octeon_cpus_done(void)239 static void octeon_cpus_done(void)
240 {
241 #ifdef CONFIG_CAVIUM_GDB
242 	unsigned long tmp;
243 	/* Pulse MCD0 signal on Ctrl-C to stop all the cores. Also set the MCD0
244 	   to be not masked by this core so we know the signal is received by
245 	   someone */
246 	asm volatile ("dmfc0 %0, $22\n"
247 		      "ori   %0, %0, 0x9100\n" "dmtc0 %0, $22\n" : "=r" (tmp));
248 #endif
249 }
250 
251 #ifdef CONFIG_HOTPLUG_CPU
252 
253 /* State of each CPU. */
254 DEFINE_PER_CPU(int, cpu_state);
255 
256 extern void fixup_irqs(void);
257 
258 static DEFINE_SPINLOCK(smp_reserve_lock);
259 
octeon_cpu_disable(void)260 static int octeon_cpu_disable(void)
261 {
262 	unsigned int cpu = smp_processor_id();
263 
264 	if (cpu == 0)
265 		return -EBUSY;
266 
267 	spin_lock(&smp_reserve_lock);
268 
269 	cpu_clear(cpu, cpu_online_map);
270 	cpu_clear(cpu, cpu_callin_map);
271 	local_irq_disable();
272 	fixup_irqs();
273 	local_irq_enable();
274 
275 	flush_cache_all();
276 	local_flush_tlb_all();
277 
278 	spin_unlock(&smp_reserve_lock);
279 
280 	return 0;
281 }
282 
octeon_cpu_die(unsigned int cpu)283 static void octeon_cpu_die(unsigned int cpu)
284 {
285 	int coreid = cpu_logical_map(cpu);
286 	uint32_t mask, new_mask;
287 	const struct cvmx_bootmem_named_block_desc *block_desc;
288 
289 	while (per_cpu(cpu_state, cpu) != CPU_DEAD)
290 		cpu_relax();
291 
292 	/*
293 	 * This is a bit complicated strategics of getting/settig available
294 	 * cores mask, copied from bootloader
295 	 */
296 
297 	mask = 1 << coreid;
298 	/* LINUX_APP_BOOT_BLOCK is initialized in bootoct binary */
299 	block_desc = cvmx_bootmem_find_named_block(LINUX_APP_BOOT_BLOCK_NAME);
300 
301 	if (!block_desc) {
302 		struct linux_app_boot_info *labi;
303 
304 		labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);
305 
306 		labi->avail_coremask |= mask;
307 		new_mask = labi->avail_coremask;
308 	} else {		       /* alternative, already initialized */
309 		uint32_t *p = (uint32_t *)PHYS_TO_XKSEG_CACHED(block_desc->base_addr +
310 							       AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK);
311 		*p |= mask;
312 		new_mask = *p;
313 	}
314 
315 	pr_info("Reset core %d. Available Coremask = 0x%x \n", coreid, new_mask);
316 	mb();
317 	cvmx_write_csr(CVMX_CIU_PP_RST, 1 << coreid);
318 	cvmx_write_csr(CVMX_CIU_PP_RST, 0);
319 }
320 
play_dead(void)321 void play_dead(void)
322 {
323 	int cpu = cpu_number_map(cvmx_get_core_num());
324 
325 	idle_task_exit();
326 	octeon_processor_boot = 0xff;
327 	per_cpu(cpu_state, cpu) = CPU_DEAD;
328 
329 	mb();
330 
331 	while (1)	/* core will be reset here */
332 		;
333 }
334 
335 extern void kernel_entry(unsigned long arg1, ...);
336 
start_after_reset(void)337 static void start_after_reset(void)
338 {
339 	kernel_entry(0, 0, 0);  /* set a2 = 0 for secondary core */
340 }
341 
octeon_update_boot_vector(unsigned int cpu)342 static int octeon_update_boot_vector(unsigned int cpu)
343 {
344 
345 	int coreid = cpu_logical_map(cpu);
346 	uint32_t avail_coremask;
347 	const struct cvmx_bootmem_named_block_desc *block_desc;
348 	struct boot_init_vector *boot_vect =
349 		(struct boot_init_vector *)PHYS_TO_XKSEG_CACHED(BOOTLOADER_BOOT_VECTOR);
350 
351 	block_desc = cvmx_bootmem_find_named_block(LINUX_APP_BOOT_BLOCK_NAME);
352 
353 	if (!block_desc) {
354 		struct linux_app_boot_info *labi;
355 
356 		labi = (struct linux_app_boot_info *)PHYS_TO_XKSEG_CACHED(LABI_ADDR_IN_BOOTLOADER);
357 
358 		avail_coremask = labi->avail_coremask;
359 		labi->avail_coremask &= ~(1 << coreid);
360 	} else {		       /* alternative, already initialized */
361 		avail_coremask = *(uint32_t *)PHYS_TO_XKSEG_CACHED(
362 			block_desc->base_addr + AVAIL_COREMASK_OFFSET_IN_LINUX_APP_BOOT_BLOCK);
363 	}
364 
365 	if (!(avail_coremask & (1 << coreid))) {
366 		/* core not available, assume, that catched by simple-executive */
367 		cvmx_write_csr(CVMX_CIU_PP_RST, 1 << coreid);
368 		cvmx_write_csr(CVMX_CIU_PP_RST, 0);
369 	}
370 
371 	boot_vect[coreid].app_start_func_addr =
372 		(uint32_t) (unsigned long) start_after_reset;
373 	boot_vect[coreid].code_addr = octeon_bootloader_entry_addr;
374 
375 	mb();
376 
377 	cvmx_write_csr(CVMX_CIU_NMI, (1 << coreid) & avail_coremask);
378 
379 	return 0;
380 }
381 
octeon_cpu_callback(struct notifier_block * nfb,unsigned long action,void * hcpu)382 static int __cpuinit octeon_cpu_callback(struct notifier_block *nfb,
383 	unsigned long action, void *hcpu)
384 {
385 	unsigned int cpu = (unsigned long)hcpu;
386 
387 	switch (action) {
388 	case CPU_UP_PREPARE:
389 		octeon_update_boot_vector(cpu);
390 		break;
391 	case CPU_ONLINE:
392 		pr_info("Cpu %d online\n", cpu);
393 		break;
394 	case CPU_DEAD:
395 		break;
396 	}
397 
398 	return NOTIFY_OK;
399 }
400 
register_cavium_notifier(void)401 static int __cpuinit register_cavium_notifier(void)
402 {
403 	hotcpu_notifier(octeon_cpu_callback, 0);
404 	return 0;
405 }
406 late_initcall(register_cavium_notifier);
407 
408 #endif  /* CONFIG_HOTPLUG_CPU */
409 
410 struct plat_smp_ops octeon_smp_ops = {
411 	.send_ipi_single	= octeon_send_ipi_single,
412 	.send_ipi_mask		= octeon_send_ipi_mask,
413 	.init_secondary		= octeon_init_secondary,
414 	.smp_finish		= octeon_smp_finish,
415 	.cpus_done		= octeon_cpus_done,
416 	.boot_secondary		= octeon_boot_secondary,
417 	.smp_setup		= octeon_smp_setup,
418 	.prepare_cpus		= octeon_prepare_cpus,
419 #ifdef CONFIG_HOTPLUG_CPU
420 	.cpu_disable		= octeon_cpu_disable,
421 	.cpu_die		= octeon_cpu_die,
422 #endif
423 };
424