1 /* sun4d_smp.c: Sparc SS1000/SC2000 SMP support.
2  *
3  * Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
4  *
5  * Based on sun4m's smp.c, which is:
6  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
7  */
8 
9 #include <asm/head.h>
10 
11 #include <linux/kernel.h>
12 #include <linux/sched.h>
13 #include <linux/threads.h>
14 #include <linux/smp.h>
15 #include <linux/smp_lock.h>
16 #include <linux/interrupt.h>
17 #include <linux/kernel_stat.h>
18 #include <linux/init.h>
19 #include <linux/spinlock.h>
20 #include <linux/mm.h>
21 
22 #include <asm/ptrace.h>
23 #include <asm/atomic.h>
24 
25 #include <asm/delay.h>
26 #include <asm/irq.h>
27 #include <asm/page.h>
28 #include <asm/pgalloc.h>
29 #include <asm/pgtable.h>
30 #include <asm/oplib.h>
31 #include <asm/hardirq.h>
32 #include <asm/softirq.h>
33 #include <asm/sbus.h>
34 #include <asm/sbi.h>
35 
36 #define __KERNEL_SYSCALLS__
37 #include <linux/unistd.h>
38 
39 #define IRQ_CROSS_CALL		15
40 
41 extern ctxd_t *srmmu_ctx_table_phys;
42 extern int linux_num_cpus;
43 
44 extern void calibrate_delay(void);
45 
46 extern struct task_struct *current_set[NR_CPUS];
47 extern volatile int smp_processors_ready;
48 extern unsigned long cpu_present_map;
49 extern int smp_num_cpus;
50 static int smp_highest_cpu;
51 extern int smp_threads_ready;
52 extern unsigned char mid_xlate[NR_CPUS];
53 extern volatile unsigned long cpu_callin_map[NR_CPUS];
54 extern unsigned long smp_proc_in_lock[NR_CPUS];
55 extern struct cpuinfo_sparc cpu_data[NR_CPUS];
56 extern unsigned long cpu_offset[NR_CPUS];
57 extern unsigned char boot_cpu_id;
58 extern int smp_activated;
59 extern volatile int __cpu_number_map[NR_CPUS];
60 extern volatile int __cpu_logical_map[NR_CPUS];
61 extern volatile unsigned long ipi_count;
62 extern volatile int smp_process_available;
63 extern volatile int smp_commenced;
64 extern int __smp4d_processor_id(void);
65 
66 extern unsigned long totalram_pages;
67 
68 /* #define SMP_DEBUG */
69 
70 #ifdef SMP_DEBUG
71 #define SMP_PRINTK(x)	printk x
72 #else
73 #define SMP_PRINTK(x)
74 #endif
75 
swap(volatile unsigned long * ptr,unsigned long val)76 static inline unsigned long swap(volatile unsigned long *ptr, unsigned long val)
77 {
78 	__asm__ __volatile__("swap [%1], %0\n\t" :
79 			     "=&r" (val), "=&r" (ptr) :
80 			     "0" (val), "1" (ptr));
81 	return val;
82 }
83 
84 static void smp_setup_percpu_timer(void);
85 extern void cpu_probe(void);
86 extern void sun4d_distribute_irqs(void);
87 
smp4d_callin(void)88 void __init smp4d_callin(void)
89 {
90 	int cpuid = hard_smp4d_processor_id();
91 	extern spinlock_t sun4d_imsk_lock;
92 	unsigned long flags;
93 
94 	/* Show we are alive */
95 	cpu_leds[cpuid] = 0x6;
96 	show_leds(cpuid);
97 
98 	/* Enable level15 interrupt, disable level14 interrupt for now */
99 	cc_set_imsk((cc_get_imsk() & ~0x8000) | 0x4000);
100 
101 	local_flush_cache_all();
102 	local_flush_tlb_all();
103 
104 	/*
105 	 * Unblock the master CPU _only_ when the scheduler state
106 	 * of all secondary CPUs will be up-to-date, so after
107 	 * the SMP initialization the master will be just allowed
108 	 * to call the scheduler code.
109 	 */
110 	init_idle();
111 
112 	/* Get our local ticker going. */
113 	smp_setup_percpu_timer();
114 
115 	calibrate_delay();
116 	smp_store_cpu_info(cpuid);
117 	local_flush_cache_all();
118 	local_flush_tlb_all();
119 
120 	/* Allow master to continue. */
121 	swap((unsigned long *)&cpu_callin_map[cpuid], 1);
122 	local_flush_cache_all();
123 	local_flush_tlb_all();
124 
125 	cpu_probe();
126 
127 	while((unsigned long)current_set[cpuid] < PAGE_OFFSET)
128 		barrier();
129 
130 	while(current_set[cpuid]->processor != cpuid)
131 		barrier();
132 
133 	/* Fix idle thread fields. */
134 	__asm__ __volatile__("ld [%0], %%g6\n\t"
135 			     : : "r" (&current_set[cpuid])
136 			     : "memory" /* paranoid */);
137 
138 	cpu_leds[cpuid] = 0x9;
139 	show_leds(cpuid);
140 
141 	/* Attach to the address space of init_task. */
142 	atomic_inc(&init_mm.mm_count);
143 	current->active_mm = &init_mm;
144 
145 	local_flush_cache_all();
146 	local_flush_tlb_all();
147 
148 	__sti();	/* We don't allow PIL 14 yet */
149 
150 	while(!smp_commenced)
151 		barrier();
152 
153 	spin_lock_irqsave(&sun4d_imsk_lock, flags);
154 	cc_set_imsk(cc_get_imsk() & ~0x4000); /* Allow PIL 14 as well */
155 	spin_unlock_irqrestore(&sun4d_imsk_lock, flags);
156 }
157 
158 extern int cpu_idle(void *unused);
159 extern void init_IRQ(void);
160 extern void cpu_panic(void);
161 extern int start_secondary(void *unused);
162 
163 /*
164  *	Cycle through the processors asking the PROM to start each one.
165  */
166 
167 extern struct prom_cpuinfo linux_cpus[NR_CPUS];
168 extern struct linux_prom_registers smp_penguin_ctable;
169 extern unsigned long trapbase_cpu1[];
170 extern unsigned long trapbase_cpu2[];
171 extern unsigned long trapbase_cpu3[];
172 
smp4d_boot_cpus(void)173 void __init smp4d_boot_cpus(void)
174 {
175 	int cpucount = 0;
176 	int i = 0;
177 
178 	printk("Entering SMP Mode...\n");
179 
180 	for (i = 0; i < NR_CPUS; i++)
181 		cpu_offset[i] = (char *)&cpu_data[i] - (char *)&cpu_data;
182 
183 	if (boot_cpu_id)
184 		current_set[0] = NULL;
185 
186 	__sti();
187 	cpu_present_map = 0;
188 	for(i=0; i < linux_num_cpus; i++)
189 		cpu_present_map |= (1<<linux_cpus[i].mid);
190 	SMP_PRINTK(("cpu_present_map %08lx\n", cpu_present_map));
191 	for(i=0; i < NR_CPUS; i++)
192 		__cpu_number_map[i] = -1;
193 	for(i=0; i < NR_CPUS; i++)
194 		__cpu_logical_map[i] = -1;
195 	for(i=0; i < NR_CPUS; i++)
196 		mid_xlate[i] = i;
197 	__cpu_number_map[boot_cpu_id] = 0;
198 	__cpu_logical_map[0] = boot_cpu_id;
199 	current->processor = boot_cpu_id;
200 	smp_store_cpu_info(boot_cpu_id);
201 	smp_setup_percpu_timer();
202 	init_idle();
203 	local_flush_cache_all();
204 	if(linux_num_cpus == 1)
205 		return;  /* Not an MP box. */
206 	SMP_PRINTK(("Iterating over CPUs\n"));
207 	for(i = 0; i < NR_CPUS; i++) {
208 		if(i == boot_cpu_id)
209 			continue;
210 
211 		if(cpu_present_map & (1 << i)) {
212 			extern unsigned long sun4d_cpu_startup;
213 			unsigned long *entry = &sun4d_cpu_startup;
214 			struct task_struct *p;
215 			int timeout;
216 			int no;
217 
218 			/* Cook up an idler for this guy. */
219 			kernel_thread(start_secondary, NULL, CLONE_PID);
220 
221 			cpucount++;
222 
223 			p = init_task.prev_task;
224 			init_tasks[i] = p;
225 
226 			p->processor = i;
227 			p->cpus_runnable = 1 << i; /* we schedule the first task manually */
228 
229 			current_set[i] = p;
230 
231 			del_from_runqueue(p);
232 			unhash_process(p);
233 
234 			for (no = 0; no < linux_num_cpus; no++)
235 				if (linux_cpus[no].mid == i)
236 					break;
237 
238 			/*
239 			 * Initialize the contexts table
240 			 * Since the call to prom_startcpu() trashes the structure,
241 			 * we need to re-initialize it for each cpu
242 			 */
243 			smp_penguin_ctable.which_io = 0;
244 			smp_penguin_ctable.phys_addr = (unsigned int) srmmu_ctx_table_phys;
245 			smp_penguin_ctable.reg_size = 0;
246 
247 			/* whirrr, whirrr, whirrrrrrrrr... */
248 			SMP_PRINTK(("Starting CPU %d at %p task %d node %08x\n", i, entry, cpucount, linux_cpus[no].prom_node));
249 			local_flush_cache_all();
250 			prom_startcpu(linux_cpus[no].prom_node,
251 				      &smp_penguin_ctable, 0, (char *)entry);
252 
253 			SMP_PRINTK(("prom_startcpu returned :)\n"));
254 
255 			/* wheee... it's going... */
256 			for(timeout = 0; timeout < 10000; timeout++) {
257 				if(cpu_callin_map[i])
258 					break;
259 				udelay(200);
260 			}
261 
262 			if(cpu_callin_map[i]) {
263 				/* Another "Red Snapper". */
264 				__cpu_number_map[i] = cpucount;
265 				__cpu_logical_map[cpucount] = i;
266 			} else {
267 				cpucount--;
268 				printk("Processor %d is stuck.\n", i);
269 			}
270 		}
271 		if(!(cpu_callin_map[i])) {
272 			cpu_present_map &= ~(1 << i);
273 			__cpu_number_map[i] = -1;
274 		}
275 	}
276 	local_flush_cache_all();
277 	if(cpucount == 0) {
278 		printk("Error: only one Processor found.\n");
279 		cpu_present_map = (1 << hard_smp4d_processor_id());
280 	} else {
281 		unsigned long bogosum = 0;
282 
283 		for(i = 0; i < NR_CPUS; i++) {
284 			if(cpu_present_map & (1 << i)) {
285 				bogosum += cpu_data[i].udelay_val;
286 				smp_highest_cpu = i;
287 			}
288 		}
289 		SMP_PRINTK(("Total of %d Processors activated (%lu.%02lu BogoMIPS).\n", cpucount + 1, bogosum/(500000/HZ), (bogosum/(5000/HZ))%100));
290 		printk("Total of %d Processors activated (%lu.%02lu BogoMIPS).\n",
291 		       cpucount + 1,
292 		       bogosum/(500000/HZ),
293 		       (bogosum/(5000/HZ))%100);
294 		smp_activated = 1;
295 		smp_num_cpus = cpucount + 1;
296 	}
297 
298 	/* Free unneeded trap tables */
299 	ClearPageReserved(virt_to_page(trapbase_cpu1));
300 	set_page_count(virt_to_page(trapbase_cpu1), 1);
301 	free_page((unsigned long)trapbase_cpu1);
302 	totalram_pages++;
303 	num_physpages++;
304 
305 	ClearPageReserved(virt_to_page(trapbase_cpu2));
306 	set_page_count(virt_to_page(trapbase_cpu2), 1);
307 	free_page((unsigned long)trapbase_cpu2);
308 	totalram_pages++;
309 	num_physpages++;
310 
311 	ClearPageReserved(virt_to_page(trapbase_cpu3));
312 	set_page_count(virt_to_page(trapbase_cpu3), 1);
313 	free_page((unsigned long)trapbase_cpu3);
314 	totalram_pages++;
315 	num_physpages++;
316 
317 	/* Ok, they are spinning and ready to go. */
318 	smp_processors_ready = 1;
319 	sun4d_distribute_irqs();
320 }
321 
322 static struct smp_funcall {
323 	smpfunc_t func;
324 	unsigned long arg1;
325 	unsigned long arg2;
326 	unsigned long arg3;
327 	unsigned long arg4;
328 	unsigned long arg5;
329 	unsigned char processors_in[NR_CPUS];  /* Set when ipi entered. */
330 	unsigned char processors_out[NR_CPUS]; /* Set when ipi exited. */
331 } ccall_info __attribute__((aligned(8)));
332 
333 static spinlock_t cross_call_lock = SPIN_LOCK_UNLOCKED;
334 
335 /* Cross calls must be serialized, at least currently. */
smp4d_cross_call(smpfunc_t func,unsigned long arg1,unsigned long arg2,unsigned long arg3,unsigned long arg4,unsigned long arg5)336 void smp4d_cross_call(smpfunc_t func, unsigned long arg1, unsigned long arg2,
337 		    unsigned long arg3, unsigned long arg4, unsigned long arg5)
338 {
339 	if(smp_processors_ready) {
340 		register int high = smp_highest_cpu;
341 		unsigned long flags;
342 
343 		spin_lock_irqsave(&cross_call_lock, flags);
344 
345 		{
346 			/* If you make changes here, make sure gcc generates proper code... */
347 			smpfunc_t f asm("i0") = func;
348 			unsigned long a1 asm("i1") = arg1;
349 			unsigned long a2 asm("i2") = arg2;
350 			unsigned long a3 asm("i3") = arg3;
351 			unsigned long a4 asm("i4") = arg4;
352 			unsigned long a5 asm("i5") = arg5;
353 
354 			__asm__ __volatile__(
355 				"std %0, [%6]\n\t"
356 				"std %2, [%6 + 8]\n\t"
357 				"std %4, [%6 + 16]\n\t" : :
358 				"r"(f), "r"(a1), "r"(a2), "r"(a3), "r"(a4), "r"(a5),
359 				"r" (&ccall_info.func));
360 		}
361 
362 		/* Init receive/complete mapping, plus fire the IPI's off. */
363 		{
364 			register unsigned long mask;
365 			register int i;
366 
367 			mask = (cpu_present_map & ~(1 << hard_smp4d_processor_id()));
368 			for(i = 0; i <= high; i++) {
369 				if(mask & (1 << i)) {
370 					ccall_info.processors_in[i] = 0;
371 					ccall_info.processors_out[i] = 0;
372 					sun4d_send_ipi(i, IRQ_CROSS_CALL);
373 				}
374 			}
375 		}
376 
377 		{
378 			register int i;
379 
380 			i = 0;
381 			do {
382 				while(!ccall_info.processors_in[i])
383 					barrier();
384 			} while(++i <= high);
385 
386 			i = 0;
387 			do {
388 				while(!ccall_info.processors_out[i])
389 					barrier();
390 			} while(++i <= high);
391 		}
392 
393 		spin_unlock_irqrestore(&cross_call_lock, flags);
394 	}
395 }
396 
397 /* Running cross calls. */
smp4d_cross_call_irq(void)398 void smp4d_cross_call_irq(void)
399 {
400 	int i = hard_smp4d_processor_id();
401 
402 	ccall_info.processors_in[i] = 1;
403 	ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
404 			ccall_info.arg4, ccall_info.arg5);
405 	ccall_info.processors_out[i] = 1;
406 }
407 
408 static int smp4d_stop_cpu_sender;
409 
smp4d_stop_cpu(void)410 static void smp4d_stop_cpu(void)
411 {
412 	int me = hard_smp4d_processor_id();
413 
414 	if (me != smp4d_stop_cpu_sender)
415 		while(1) barrier();
416 }
417 
418 /* Cross calls, in order to work efficiently and atomically do all
419  * the message passing work themselves, only stopcpu and reschedule
420  * messages come through here.
421  */
smp4d_message_pass(int target,int msg,unsigned long data,int wait)422 void smp4d_message_pass(int target, int msg, unsigned long data, int wait)
423 {
424 	int me = hard_smp4d_processor_id();
425 
426 	SMP_PRINTK(("smp4d_message_pass %d %d %08lx %d\n", target, msg, data, wait));
427 	if (msg == MSG_STOP_CPU && target == MSG_ALL_BUT_SELF) {
428 		unsigned long flags;
429 		static spinlock_t stop_cpu_lock = SPIN_LOCK_UNLOCKED;
430 		spin_lock_irqsave(&stop_cpu_lock, flags);
431 		smp4d_stop_cpu_sender = me;
432 		smp4d_cross_call((smpfunc_t)smp4d_stop_cpu, 0, 0, 0, 0, 0);
433 		spin_unlock_irqrestore(&stop_cpu_lock, flags);
434 	}
435 	printk("Yeeee, trying to send SMP msg(%d) to %d on cpu %d\n", msg, target, me);
436 	panic("Bogon SMP message pass.");
437 }
438 
439 extern unsigned int prof_multiplier[NR_CPUS];
440 extern unsigned int prof_counter[NR_CPUS];
441 
442 extern void sparc_do_profile(unsigned long pc, unsigned long o7);
443 
smp4d_percpu_timer_interrupt(struct pt_regs * regs)444 void smp4d_percpu_timer_interrupt(struct pt_regs *regs)
445 {
446 	int cpu = hard_smp4d_processor_id();
447 	static int cpu_tick[NR_CPUS];
448 	static char led_mask[] = { 0xe, 0xd, 0xb, 0x7, 0xb, 0xd };
449 
450 	bw_get_prof_limit(cpu);
451 	bw_clear_intr_mask(0, 1);	/* INTR_TABLE[0] & 1 is Profile IRQ */
452 
453 	cpu_tick[cpu]++;
454 	if (!(cpu_tick[cpu] & 15)) {
455 		if (cpu_tick[cpu] == 0x60)
456 			cpu_tick[cpu] = 0;
457 		cpu_leds[cpu] = led_mask[cpu_tick[cpu] >> 4];
458 		show_leds(cpu);
459 	}
460 
461 	if(!user_mode(regs))
462 		sparc_do_profile(regs->pc, regs->u_regs[UREG_RETPC]);
463 
464 	if(!--prof_counter[cpu]) {
465 		int user = user_mode(regs);
466 
467 		irq_enter(cpu, 0);
468 		update_process_times(user);
469 		irq_exit(cpu, 0);
470 
471 		prof_counter[cpu] = prof_multiplier[cpu];
472 	}
473 }
474 
475 extern unsigned int lvl14_resolution;
476 
smp_setup_percpu_timer(void)477 static void __init smp_setup_percpu_timer(void)
478 {
479 	int cpu = hard_smp4d_processor_id();
480 
481 	prof_counter[cpu] = prof_multiplier[cpu] = 1;
482 	load_profile_irq(cpu, lvl14_resolution);
483 }
484 
smp4d_blackbox_id(unsigned * addr)485 void __init smp4d_blackbox_id(unsigned *addr)
486 {
487 	int rd = *addr & 0x3e000000;
488 
489 	addr[0] = 0xc0800800 | rd;		/* lda [%g0] ASI_M_VIKING_TMP1, reg */
490 	addr[1] = 0x01000000;    		/* nop */
491 	addr[2] = 0x01000000;    		/* nop */
492 }
493 
smp4d_blackbox_current(unsigned * addr)494 void __init smp4d_blackbox_current(unsigned *addr)
495 {
496 	int rd = *addr & 0x3e000000;
497 
498 	addr[0] = 0xc0800800 | rd;		/* lda [%g0] ASI_M_VIKING_TMP1, reg */
499 	addr[2] = 0x81282002 | rd | (rd >> 11);	/* sll reg, 2, reg */
500 	addr[4] = 0x01000000;			/* nop */
501 }
502 
sun4d_init_smp(void)503 void __init sun4d_init_smp(void)
504 {
505 	int i;
506 	extern unsigned int t_nmi[], linux_trap_ipi15_sun4d[], linux_trap_ipi15_sun4m[];
507 
508 	/* Patch ipi15 trap table */
509 	t_nmi[1] = t_nmi[1] + (linux_trap_ipi15_sun4d - linux_trap_ipi15_sun4m);
510 
511 	/* And set btfixup... */
512 	BTFIXUPSET_BLACKBOX(smp_processor_id, smp4d_blackbox_id);
513 	BTFIXUPSET_BLACKBOX(load_current, smp4d_blackbox_current);
514 	BTFIXUPSET_CALL(smp_cross_call, smp4d_cross_call, BTFIXUPCALL_NORM);
515 	BTFIXUPSET_CALL(smp_message_pass, smp4d_message_pass, BTFIXUPCALL_NORM);
516 	BTFIXUPSET_CALL(__smp_processor_id, __smp4d_processor_id, BTFIXUPCALL_NORM);
517 
518 	for (i = 0; i < NR_CPUS; i++) {
519 		ccall_info.processors_in[i] = 1;
520 		ccall_info.processors_out[i] = 1;
521 	}
522 }
523