xref: /linux/arch/sparc/kernel/sun4m_smp.c (revision de2fe5e07d58424bc286fff3fd3c1b0bf933cd58)
1 /* sun4m_smp.c: Sparc SUN4M SMP support.
2  *
3  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
4  */
5 
6 #include <asm/head.h>
7 
8 #include <linux/kernel.h>
9 #include <linux/sched.h>
10 #include <linux/threads.h>
11 #include <linux/smp.h>
12 #include <linux/smp_lock.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel_stat.h>
15 #include <linux/init.h>
16 #include <linux/spinlock.h>
17 #include <linux/mm.h>
18 #include <linux/swap.h>
19 #include <linux/profile.h>
20 #include <asm/cacheflush.h>
21 #include <asm/tlbflush.h>
22 
23 #include <asm/ptrace.h>
24 #include <asm/atomic.h>
25 
26 #include <asm/delay.h>
27 #include <asm/irq.h>
28 #include <asm/page.h>
29 #include <asm/pgalloc.h>
30 #include <asm/pgtable.h>
31 #include <asm/oplib.h>
32 #include <asm/cpudata.h>
33 
34 #define IRQ_RESCHEDULE		13
35 #define IRQ_STOP_CPU		14
36 #define IRQ_CROSS_CALL		15
37 
38 extern ctxd_t *srmmu_ctx_table_phys;
39 
40 extern void calibrate_delay(void);
41 
42 extern volatile int smp_processors_ready;
43 extern volatile unsigned long cpu_callin_map[NR_CPUS];
44 extern unsigned char boot_cpu_id;
45 
46 extern cpumask_t smp_commenced_mask;
47 
48 extern int __smp4m_processor_id(void);
49 
50 /*#define SMP_DEBUG*/
51 
52 #ifdef SMP_DEBUG
53 #define SMP_PRINTK(x)	printk x
54 #else
55 #define SMP_PRINTK(x)
56 #endif
57 
58 static inline unsigned long swap(volatile unsigned long *ptr, unsigned long val)
59 {
60 	__asm__ __volatile__("swap [%1], %0\n\t" :
61 			     "=&r" (val), "=&r" (ptr) :
62 			     "0" (val), "1" (ptr));
63 	return val;
64 }
65 
66 static void smp_setup_percpu_timer(void);
67 extern void cpu_probe(void);
68 
69 void __init smp4m_callin(void)
70 {
71 	int cpuid = hard_smp_processor_id();
72 
73 	local_flush_cache_all();
74 	local_flush_tlb_all();
75 
76 	/* Get our local ticker going. */
77 	smp_setup_percpu_timer();
78 
79 	calibrate_delay();
80 	smp_store_cpu_info(cpuid);
81 
82 	local_flush_cache_all();
83 	local_flush_tlb_all();
84 
85 	/*
86 	 * Unblock the master CPU _only_ when the scheduler state
87 	 * of all secondary CPUs will be up-to-date, so after
88 	 * the SMP initialization the master will be just allowed
89 	 * to call the scheduler code.
90 	 */
91 	/* Allow master to continue. */
92 	swap(&cpu_callin_map[cpuid], 1);
93 
94 	/* XXX: What's up with all the flushes? */
95 	local_flush_cache_all();
96 	local_flush_tlb_all();
97 
98 	cpu_probe();
99 
100 	/* Fix idle thread fields. */
101 	__asm__ __volatile__("ld [%0], %%g6\n\t"
102 			     : : "r" (&current_set[cpuid])
103 			     : "memory" /* paranoid */);
104 
105 	/* Attach to the address space of init_task. */
106 	atomic_inc(&init_mm.mm_count);
107 	current->active_mm = &init_mm;
108 
109 	while (!cpu_isset(cpuid, smp_commenced_mask))
110 		mb();
111 
112 	local_irq_enable();
113 
114 	cpu_set(cpuid, cpu_online_map);
115 	/* last one in gets all the interrupts (for testing) */
116 	set_irq_udt(boot_cpu_id);
117 }
118 
119 extern void init_IRQ(void);
120 extern void cpu_panic(void);
121 
122 /*
123  *	Cycle through the processors asking the PROM to start each one.
124  */
125 
126 extern struct linux_prom_registers smp_penguin_ctable;
127 extern unsigned long trapbase_cpu1[];
128 extern unsigned long trapbase_cpu2[];
129 extern unsigned long trapbase_cpu3[];
130 
131 void __init smp4m_boot_cpus(void)
132 {
133 	smp_setup_percpu_timer();
134 	local_flush_cache_all();
135 }
136 
137 int smp4m_boot_one_cpu(int i)
138 {
139 	extern unsigned long sun4m_cpu_startup;
140 	unsigned long *entry = &sun4m_cpu_startup;
141 	struct task_struct *p;
142 	int timeout;
143 	int cpu_node;
144 
145 	cpu_find_by_mid(i, &cpu_node);
146 
147 	/* Cook up an idler for this guy. */
148 	p = fork_idle(i);
149 	current_set[i] = task_thread_info(p);
150 	/* See trampoline.S for details... */
151 	entry += ((i-1) * 3);
152 
153 	/*
154 	 * Initialize the contexts table
155 	 * Since the call to prom_startcpu() trashes the structure,
156 	 * we need to re-initialize it for each cpu
157 	 */
158 	smp_penguin_ctable.which_io = 0;
159 	smp_penguin_ctable.phys_addr = (unsigned int) srmmu_ctx_table_phys;
160 	smp_penguin_ctable.reg_size = 0;
161 
162 	/* whirrr, whirrr, whirrrrrrrrr... */
163 	printk("Starting CPU %d at %p\n", i, entry);
164 	local_flush_cache_all();
165 	prom_startcpu(cpu_node,
166 		      &smp_penguin_ctable, 0, (char *)entry);
167 
168 	/* wheee... it's going... */
169 	for(timeout = 0; timeout < 10000; timeout++) {
170 		if(cpu_callin_map[i])
171 			break;
172 		udelay(200);
173 	}
174 
175 	if (!(cpu_callin_map[i])) {
176 		printk("Processor %d is stuck.\n", i);
177 		return -ENODEV;
178 	}
179 
180 	local_flush_cache_all();
181 	return 0;
182 }
183 
184 void __init smp4m_smp_done(void)
185 {
186 	int i, first;
187 	int *prev;
188 
189 	/* setup cpu list for irq rotation */
190 	first = 0;
191 	prev = &first;
192 	for (i = 0; i < NR_CPUS; i++) {
193 		if (cpu_online(i)) {
194 			*prev = i;
195 			prev = &cpu_data(i).next;
196 		}
197 	}
198 	*prev = first;
199 	local_flush_cache_all();
200 
201 	/* Free unneeded trap tables */
202 	if (!cpu_isset(1, cpu_present_map)) {
203 		ClearPageReserved(virt_to_page(trapbase_cpu1));
204 		init_page_count(virt_to_page(trapbase_cpu1));
205 		free_page((unsigned long)trapbase_cpu1);
206 		totalram_pages++;
207 		num_physpages++;
208 	}
209 	if (!cpu_isset(2, cpu_present_map)) {
210 		ClearPageReserved(virt_to_page(trapbase_cpu2));
211 		init_page_count(virt_to_page(trapbase_cpu2));
212 		free_page((unsigned long)trapbase_cpu2);
213 		totalram_pages++;
214 		num_physpages++;
215 	}
216 	if (!cpu_isset(3, cpu_present_map)) {
217 		ClearPageReserved(virt_to_page(trapbase_cpu3));
218 		init_page_count(virt_to_page(trapbase_cpu3));
219 		free_page((unsigned long)trapbase_cpu3);
220 		totalram_pages++;
221 		num_physpages++;
222 	}
223 
224 	/* Ok, they are spinning and ready to go. */
225 	smp_processors_ready = 1;
226 }
227 
228 /* At each hardware IRQ, we get this called to forward IRQ reception
229  * to the next processor.  The caller must disable the IRQ level being
230  * serviced globally so that there are no double interrupts received.
231  *
232  * XXX See sparc64 irq.c.
233  */
234 void smp4m_irq_rotate(int cpu)
235 {
236 	int next = cpu_data(cpu).next;
237 	if (next != cpu)
238 		set_irq_udt(next);
239 }
240 
241 /* Cross calls, in order to work efficiently and atomically do all
242  * the message passing work themselves, only stopcpu and reschedule
243  * messages come through here.
244  */
245 void smp4m_message_pass(int target, int msg, unsigned long data, int wait)
246 {
247 	static unsigned long smp_cpu_in_msg[NR_CPUS];
248 	cpumask_t mask;
249 	int me = smp_processor_id();
250 	int irq, i;
251 
252 	if(msg == MSG_RESCHEDULE) {
253 		irq = IRQ_RESCHEDULE;
254 
255 		if(smp_cpu_in_msg[me])
256 			return;
257 	} else if(msg == MSG_STOP_CPU) {
258 		irq = IRQ_STOP_CPU;
259 	} else {
260 		goto barf;
261 	}
262 
263 	smp_cpu_in_msg[me]++;
264 	if(target == MSG_ALL_BUT_SELF || target == MSG_ALL) {
265 		mask = cpu_online_map;
266 		if(target == MSG_ALL_BUT_SELF)
267 			cpu_clear(me, mask);
268 		for(i = 0; i < 4; i++) {
269 			if (cpu_isset(i, mask))
270 				set_cpu_int(i, irq);
271 		}
272 	} else {
273 		set_cpu_int(target, irq);
274 	}
275 	smp_cpu_in_msg[me]--;
276 
277 	return;
278 barf:
279 	printk("Yeeee, trying to send SMP msg(%d) on cpu %d\n", msg, me);
280 	panic("Bogon SMP message pass.");
281 }
282 
283 static struct smp_funcall {
284 	smpfunc_t func;
285 	unsigned long arg1;
286 	unsigned long arg2;
287 	unsigned long arg3;
288 	unsigned long arg4;
289 	unsigned long arg5;
290 	unsigned long processors_in[SUN4M_NCPUS];  /* Set when ipi entered. */
291 	unsigned long processors_out[SUN4M_NCPUS]; /* Set when ipi exited. */
292 } ccall_info;
293 
294 static DEFINE_SPINLOCK(cross_call_lock);
295 
296 /* Cross calls must be serialized, at least currently. */
297 void smp4m_cross_call(smpfunc_t func, unsigned long arg1, unsigned long arg2,
298 		    unsigned long arg3, unsigned long arg4, unsigned long arg5)
299 {
300 		register int ncpus = SUN4M_NCPUS;
301 		unsigned long flags;
302 
303 		spin_lock_irqsave(&cross_call_lock, flags);
304 
305 		/* Init function glue. */
306 		ccall_info.func = func;
307 		ccall_info.arg1 = arg1;
308 		ccall_info.arg2 = arg2;
309 		ccall_info.arg3 = arg3;
310 		ccall_info.arg4 = arg4;
311 		ccall_info.arg5 = arg5;
312 
313 		/* Init receive/complete mapping, plus fire the IPI's off. */
314 		{
315 			cpumask_t mask = cpu_online_map;
316 			register int i;
317 
318 			cpu_clear(smp_processor_id(), mask);
319 			for(i = 0; i < ncpus; i++) {
320 				if (cpu_isset(i, mask)) {
321 					ccall_info.processors_in[i] = 0;
322 					ccall_info.processors_out[i] = 0;
323 					set_cpu_int(i, IRQ_CROSS_CALL);
324 				} else {
325 					ccall_info.processors_in[i] = 1;
326 					ccall_info.processors_out[i] = 1;
327 				}
328 			}
329 		}
330 
331 		{
332 			register int i;
333 
334 			i = 0;
335 			do {
336 				while(!ccall_info.processors_in[i])
337 					barrier();
338 			} while(++i < ncpus);
339 
340 			i = 0;
341 			do {
342 				while(!ccall_info.processors_out[i])
343 					barrier();
344 			} while(++i < ncpus);
345 		}
346 
347 		spin_unlock_irqrestore(&cross_call_lock, flags);
348 }
349 
350 /* Running cross calls. */
351 void smp4m_cross_call_irq(void)
352 {
353 	int i = smp_processor_id();
354 
355 	ccall_info.processors_in[i] = 1;
356 	ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
357 			ccall_info.arg4, ccall_info.arg5);
358 	ccall_info.processors_out[i] = 1;
359 }
360 
361 void smp4m_percpu_timer_interrupt(struct pt_regs *regs)
362 {
363 	int cpu = smp_processor_id();
364 
365 	clear_profile_irq(cpu);
366 
367 	profile_tick(CPU_PROFILING, regs);
368 
369 	if(!--prof_counter(cpu)) {
370 		int user = user_mode(regs);
371 
372 		irq_enter();
373 		update_process_times(user);
374 		irq_exit();
375 
376 		prof_counter(cpu) = prof_multiplier(cpu);
377 	}
378 }
379 
380 extern unsigned int lvl14_resolution;
381 
382 static void __init smp_setup_percpu_timer(void)
383 {
384 	int cpu = smp_processor_id();
385 
386 	prof_counter(cpu) = prof_multiplier(cpu) = 1;
387 	load_profile_irq(cpu, lvl14_resolution);
388 
389 	if(cpu == boot_cpu_id)
390 		enable_pil_irq(14);
391 }
392 
393 void __init smp4m_blackbox_id(unsigned *addr)
394 {
395 	int rd = *addr & 0x3e000000;
396 	int rs1 = rd >> 11;
397 
398 	addr[0] = 0x81580000 | rd;		/* rd %tbr, reg */
399 	addr[1] = 0x8130200c | rd | rs1;    	/* srl reg, 0xc, reg */
400 	addr[2] = 0x80082003 | rd | rs1;	/* and reg, 3, reg */
401 }
402 
403 void __init smp4m_blackbox_current(unsigned *addr)
404 {
405 	int rd = *addr & 0x3e000000;
406 	int rs1 = rd >> 11;
407 
408 	addr[0] = 0x81580000 | rd;		/* rd %tbr, reg */
409 	addr[2] = 0x8130200a | rd | rs1;    	/* srl reg, 0xa, reg */
410 	addr[4] = 0x8008200c | rd | rs1;	/* and reg, 3, reg */
411 }
412 
413 void __init sun4m_init_smp(void)
414 {
415 	BTFIXUPSET_BLACKBOX(hard_smp_processor_id, smp4m_blackbox_id);
416 	BTFIXUPSET_BLACKBOX(load_current, smp4m_blackbox_current);
417 	BTFIXUPSET_CALL(smp_cross_call, smp4m_cross_call, BTFIXUPCALL_NORM);
418 	BTFIXUPSET_CALL(smp_message_pass, smp4m_message_pass, BTFIXUPCALL_NORM);
419 	BTFIXUPSET_CALL(__hard_smp_processor_id, __smp4m_processor_id, BTFIXUPCALL_NORM);
420 }
421