1 /* 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 <linux/interrupt.h>
10 #include <linux/profile.h>
11 #include <linux/delay.h>
12 #include <linux/cpu.h>
13 
14 #include <asm/sbi.h>
15 #include <asm/mmu.h>
16 #include <asm/tlbflush.h>
17 #include <asm/switch_to.h>
18 #include <asm/cacheflush.h>
19 
20 #include "kernel.h"
21 #include "irq.h"
22 
23 #define IRQ_CROSS_CALL		15
24 
25 static volatile int smp_processors_ready;
26 static int smp_highest_cpu;
27 
sun4d_swap(volatile unsigned long * ptr,unsigned long val)28 static inline unsigned long sun4d_swap(volatile unsigned long *ptr, unsigned long val)
29 {
30 	__asm__ __volatile__("swap [%1], %0\n\t" :
31 			     "=&r" (val), "=&r" (ptr) :
32 			     "0" (val), "1" (ptr));
33 	return val;
34 }
35 
36 static void smp4d_ipi_init(void);
37 static void smp_setup_percpu_timer(void);
38 
39 static unsigned char cpu_leds[32];
40 
show_leds(int cpuid)41 static inline void show_leds(int cpuid)
42 {
43 	cpuid &= 0x1e;
44 	__asm__ __volatile__ ("stba %0, [%1] %2" : :
45 			      "r" ((cpu_leds[cpuid] << 4) | cpu_leds[cpuid+1]),
46 			      "r" (ECSR_BASE(cpuid) | BB_LEDS),
47 			      "i" (ASI_M_CTL));
48 }
49 
smp4d_callin(void)50 void __cpuinit smp4d_callin(void)
51 {
52 	int cpuid = hard_smp4d_processor_id();
53 	unsigned long flags;
54 
55 	/* Show we are alive */
56 	cpu_leds[cpuid] = 0x6;
57 	show_leds(cpuid);
58 
59 	/* Enable level15 interrupt, disable level14 interrupt for now */
60 	cc_set_imsk((cc_get_imsk() & ~0x8000) | 0x4000);
61 
62 	local_flush_cache_all();
63 	local_flush_tlb_all();
64 
65 	notify_cpu_starting(cpuid);
66 	/*
67 	 * Unblock the master CPU _only_ when the scheduler state
68 	 * of all secondary CPUs will be up-to-date, so after
69 	 * the SMP initialization the master will be just allowed
70 	 * to call the scheduler code.
71 	 */
72 	/* Get our local ticker going. */
73 	smp_setup_percpu_timer();
74 
75 	calibrate_delay();
76 	smp_store_cpu_info(cpuid);
77 	local_flush_cache_all();
78 	local_flush_tlb_all();
79 
80 	/* Allow master to continue. */
81 	sun4d_swap((unsigned long *)&cpu_callin_map[cpuid], 1);
82 	local_flush_cache_all();
83 	local_flush_tlb_all();
84 
85 	while ((unsigned long)current_set[cpuid] < PAGE_OFFSET)
86 		barrier();
87 
88 	while (current_set[cpuid]->cpu != cpuid)
89 		barrier();
90 
91 	/* Fix idle thread fields. */
92 	__asm__ __volatile__("ld [%0], %%g6\n\t"
93 			     : : "r" (&current_set[cpuid])
94 			     : "memory" /* paranoid */);
95 
96 	cpu_leds[cpuid] = 0x9;
97 	show_leds(cpuid);
98 
99 	/* Attach to the address space of init_task. */
100 	atomic_inc(&init_mm.mm_count);
101 	current->active_mm = &init_mm;
102 
103 	local_flush_cache_all();
104 	local_flush_tlb_all();
105 
106 	local_irq_enable();	/* We don't allow PIL 14 yet */
107 
108 	while (!cpumask_test_cpu(cpuid, &smp_commenced_mask))
109 		barrier();
110 
111 	spin_lock_irqsave(&sun4d_imsk_lock, flags);
112 	cc_set_imsk(cc_get_imsk() & ~0x4000); /* Allow PIL 14 as well */
113 	spin_unlock_irqrestore(&sun4d_imsk_lock, flags);
114 	set_cpu_online(cpuid, true);
115 
116 }
117 
118 /*
119  *	Cycle through the processors asking the PROM to start each one.
120  */
smp4d_boot_cpus(void)121 void __init smp4d_boot_cpus(void)
122 {
123 	smp4d_ipi_init();
124 	if (boot_cpu_id)
125 		current_set[0] = NULL;
126 	smp_setup_percpu_timer();
127 	local_flush_cache_all();
128 }
129 
smp4d_boot_one_cpu(int i)130 int __cpuinit smp4d_boot_one_cpu(int i)
131 {
132 	unsigned long *entry = &sun4d_cpu_startup;
133 	struct task_struct *p;
134 	int timeout;
135 	int cpu_node;
136 
137 	cpu_find_by_instance(i, &cpu_node, NULL);
138 	/* Cook up an idler for this guy. */
139 	p = fork_idle(i);
140 	current_set[i] = task_thread_info(p);
141 
142 	/*
143 	 * Initialize the contexts table
144 	 * Since the call to prom_startcpu() trashes the structure,
145 	 * we need to re-initialize it for each cpu
146 	 */
147 	smp_penguin_ctable.which_io = 0;
148 	smp_penguin_ctable.phys_addr = (unsigned int) srmmu_ctx_table_phys;
149 	smp_penguin_ctable.reg_size = 0;
150 
151 	/* whirrr, whirrr, whirrrrrrrrr... */
152 	printk(KERN_INFO "Starting CPU %d at %p\n", i, entry);
153 	local_flush_cache_all();
154 	prom_startcpu(cpu_node,
155 		      &smp_penguin_ctable, 0, (char *)entry);
156 
157 	printk(KERN_INFO "prom_startcpu returned :)\n");
158 
159 	/* wheee... it's going... */
160 	for (timeout = 0; timeout < 10000; timeout++) {
161 		if (cpu_callin_map[i])
162 			break;
163 		udelay(200);
164 	}
165 
166 	if (!(cpu_callin_map[i])) {
167 		printk(KERN_ERR "Processor %d is stuck.\n", i);
168 		return -ENODEV;
169 
170 	}
171 	local_flush_cache_all();
172 	return 0;
173 }
174 
smp4d_smp_done(void)175 void __init smp4d_smp_done(void)
176 {
177 	int i, first;
178 	int *prev;
179 
180 	/* setup cpu list for irq rotation */
181 	first = 0;
182 	prev = &first;
183 	for_each_online_cpu(i) {
184 		*prev = i;
185 		prev = &cpu_data(i).next;
186 	}
187 	*prev = first;
188 	local_flush_cache_all();
189 
190 	/* Ok, they are spinning and ready to go. */
191 	smp_processors_ready = 1;
192 	sun4d_distribute_irqs();
193 }
194 
195 /* Memory structure giving interrupt handler information about IPI generated */
196 struct sun4d_ipi_work {
197 	int single;
198 	int msk;
199 	int resched;
200 };
201 
202 static DEFINE_PER_CPU_SHARED_ALIGNED(struct sun4d_ipi_work, sun4d_ipi_work);
203 
204 /* Initialize IPIs on the SUN4D SMP machine */
smp4d_ipi_init(void)205 static void __init smp4d_ipi_init(void)
206 {
207 	int cpu;
208 	struct sun4d_ipi_work *work;
209 
210 	printk(KERN_INFO "smp4d: setup IPI at IRQ %d\n", SUN4D_IPI_IRQ);
211 
212 	for_each_possible_cpu(cpu) {
213 		work = &per_cpu(sun4d_ipi_work, cpu);
214 		work->single = work->msk = work->resched = 0;
215 	}
216 }
217 
sun4d_ipi_interrupt(void)218 void sun4d_ipi_interrupt(void)
219 {
220 	struct sun4d_ipi_work *work = &__get_cpu_var(sun4d_ipi_work);
221 
222 	if (work->single) {
223 		work->single = 0;
224 		smp_call_function_single_interrupt();
225 	}
226 	if (work->msk) {
227 		work->msk = 0;
228 		smp_call_function_interrupt();
229 	}
230 	if (work->resched) {
231 		work->resched = 0;
232 		smp_resched_interrupt();
233 	}
234 }
235 
smp4d_ipi_single(int cpu)236 static void smp4d_ipi_single(int cpu)
237 {
238 	struct sun4d_ipi_work *work = &per_cpu(sun4d_ipi_work, cpu);
239 
240 	/* Mark work */
241 	work->single = 1;
242 
243 	/* Generate IRQ on the CPU */
244 	sun4d_send_ipi(cpu, SUN4D_IPI_IRQ);
245 }
246 
smp4d_ipi_mask_one(int cpu)247 static void smp4d_ipi_mask_one(int cpu)
248 {
249 	struct sun4d_ipi_work *work = &per_cpu(sun4d_ipi_work, cpu);
250 
251 	/* Mark work */
252 	work->msk = 1;
253 
254 	/* Generate IRQ on the CPU */
255 	sun4d_send_ipi(cpu, SUN4D_IPI_IRQ);
256 }
257 
smp4d_ipi_resched(int cpu)258 static void smp4d_ipi_resched(int cpu)
259 {
260 	struct sun4d_ipi_work *work = &per_cpu(sun4d_ipi_work, cpu);
261 
262 	/* Mark work */
263 	work->resched = 1;
264 
265 	/* Generate IRQ on the CPU (any IRQ will cause resched) */
266 	sun4d_send_ipi(cpu, SUN4D_IPI_IRQ);
267 }
268 
269 static struct smp_funcall {
270 	smpfunc_t func;
271 	unsigned long arg1;
272 	unsigned long arg2;
273 	unsigned long arg3;
274 	unsigned long arg4;
275 	unsigned long arg5;
276 	unsigned char processors_in[NR_CPUS];  /* Set when ipi entered. */
277 	unsigned char processors_out[NR_CPUS]; /* Set when ipi exited. */
278 } ccall_info __attribute__((aligned(8)));
279 
280 static DEFINE_SPINLOCK(cross_call_lock);
281 
282 /* Cross calls must be serialized, at least currently. */
smp4d_cross_call(smpfunc_t func,cpumask_t mask,unsigned long arg1,unsigned long arg2,unsigned long arg3,unsigned long arg4)283 static void smp4d_cross_call(smpfunc_t func, cpumask_t mask, unsigned long arg1,
284 			     unsigned long arg2, unsigned long arg3,
285 			     unsigned long arg4)
286 {
287 	if (smp_processors_ready) {
288 		register int high = smp_highest_cpu;
289 		unsigned long flags;
290 
291 		spin_lock_irqsave(&cross_call_lock, flags);
292 
293 		{
294 			/*
295 			 * If you make changes here, make sure
296 			 * gcc generates proper code...
297 			 */
298 			register smpfunc_t f asm("i0") = func;
299 			register unsigned long a1 asm("i1") = arg1;
300 			register unsigned long a2 asm("i2") = arg2;
301 			register unsigned long a3 asm("i3") = arg3;
302 			register unsigned long a4 asm("i4") = arg4;
303 			register unsigned long a5 asm("i5") = 0;
304 
305 			__asm__ __volatile__(
306 				"std %0, [%6]\n\t"
307 				"std %2, [%6 + 8]\n\t"
308 				"std %4, [%6 + 16]\n\t" : :
309 				"r"(f), "r"(a1), "r"(a2), "r"(a3), "r"(a4), "r"(a5),
310 				"r" (&ccall_info.func));
311 		}
312 
313 		/* Init receive/complete mapping, plus fire the IPI's off. */
314 		{
315 			register int i;
316 
317 			cpumask_clear_cpu(smp_processor_id(), &mask);
318 			cpumask_and(&mask, cpu_online_mask, &mask);
319 			for (i = 0; i <= high; i++) {
320 				if (cpumask_test_cpu(i, &mask)) {
321 					ccall_info.processors_in[i] = 0;
322 					ccall_info.processors_out[i] = 0;
323 					sun4d_send_ipi(i, IRQ_CROSS_CALL);
324 				}
325 			}
326 		}
327 
328 		{
329 			register int i;
330 
331 			i = 0;
332 			do {
333 				if (!cpumask_test_cpu(i, &mask))
334 					continue;
335 				while (!ccall_info.processors_in[i])
336 					barrier();
337 			} while (++i <= high);
338 
339 			i = 0;
340 			do {
341 				if (!cpumask_test_cpu(i, &mask))
342 					continue;
343 				while (!ccall_info.processors_out[i])
344 					barrier();
345 			} while (++i <= high);
346 		}
347 
348 		spin_unlock_irqrestore(&cross_call_lock, flags);
349 	}
350 }
351 
352 /* Running cross calls. */
smp4d_cross_call_irq(void)353 void smp4d_cross_call_irq(void)
354 {
355 	int i = hard_smp4d_processor_id();
356 
357 	ccall_info.processors_in[i] = 1;
358 	ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
359 			ccall_info.arg4, ccall_info.arg5);
360 	ccall_info.processors_out[i] = 1;
361 }
362 
smp4d_percpu_timer_interrupt(struct pt_regs * regs)363 void smp4d_percpu_timer_interrupt(struct pt_regs *regs)
364 {
365 	struct pt_regs *old_regs;
366 	int cpu = hard_smp4d_processor_id();
367 	static int cpu_tick[NR_CPUS];
368 	static char led_mask[] = { 0xe, 0xd, 0xb, 0x7, 0xb, 0xd };
369 
370 	old_regs = set_irq_regs(regs);
371 	bw_get_prof_limit(cpu);
372 	bw_clear_intr_mask(0, 1);	/* INTR_TABLE[0] & 1 is Profile IRQ */
373 
374 	cpu_tick[cpu]++;
375 	if (!(cpu_tick[cpu] & 15)) {
376 		if (cpu_tick[cpu] == 0x60)
377 			cpu_tick[cpu] = 0;
378 		cpu_leds[cpu] = led_mask[cpu_tick[cpu] >> 4];
379 		show_leds(cpu);
380 	}
381 
382 	profile_tick(CPU_PROFILING);
383 
384 	if (!--prof_counter(cpu)) {
385 		int user = user_mode(regs);
386 
387 		irq_enter();
388 		update_process_times(user);
389 		irq_exit();
390 
391 		prof_counter(cpu) = prof_multiplier(cpu);
392 	}
393 	set_irq_regs(old_regs);
394 }
395 
smp_setup_percpu_timer(void)396 static void __cpuinit smp_setup_percpu_timer(void)
397 {
398 	int cpu = hard_smp4d_processor_id();
399 
400 	prof_counter(cpu) = prof_multiplier(cpu) = 1;
401 	load_profile_irq(cpu, lvl14_resolution);
402 }
403 
smp4d_blackbox_id(unsigned * addr)404 void __init smp4d_blackbox_id(unsigned *addr)
405 {
406 	int rd = *addr & 0x3e000000;
407 
408 	addr[0] = 0xc0800800 | rd;		/* lda [%g0] ASI_M_VIKING_TMP1, reg */
409 	addr[1] = 0x01000000;			/* nop */
410 	addr[2] = 0x01000000;			/* nop */
411 }
412 
smp4d_blackbox_current(unsigned * addr)413 void __init smp4d_blackbox_current(unsigned *addr)
414 {
415 	int rd = *addr & 0x3e000000;
416 
417 	addr[0] = 0xc0800800 | rd;		/* lda [%g0] ASI_M_VIKING_TMP1, reg */
418 	addr[2] = 0x81282002 | rd | (rd >> 11);	/* sll reg, 2, reg */
419 	addr[4] = 0x01000000;			/* nop */
420 }
421 
sun4d_init_smp(void)422 void __init sun4d_init_smp(void)
423 {
424 	int i;
425 
426 	/* Patch ipi15 trap table */
427 	t_nmi[1] = t_nmi[1] + (linux_trap_ipi15_sun4d - linux_trap_ipi15_sun4m);
428 
429 	/* And set btfixup... */
430 	BTFIXUPSET_BLACKBOX(hard_smp_processor_id, smp4d_blackbox_id);
431 	BTFIXUPSET_BLACKBOX(load_current, smp4d_blackbox_current);
432 	BTFIXUPSET_CALL(smp_cross_call, smp4d_cross_call, BTFIXUPCALL_NORM);
433 	BTFIXUPSET_CALL(__hard_smp_processor_id, __smp4d_processor_id, BTFIXUPCALL_NORM);
434 	BTFIXUPSET_CALL(smp_ipi_resched, smp4d_ipi_resched, BTFIXUPCALL_NORM);
435 	BTFIXUPSET_CALL(smp_ipi_single, smp4d_ipi_single, BTFIXUPCALL_NORM);
436 	BTFIXUPSET_CALL(smp_ipi_mask_one, smp4d_ipi_mask_one, BTFIXUPCALL_NORM);
437 
438 	for (i = 0; i < NR_CPUS; i++) {
439 		ccall_info.processors_in[i] = 1;
440 		ccall_info.processors_out[i] = 1;
441 	}
442 }
443