xref: /linux/arch/sparc/kernel/leon_smp.c (revision e9fb13bfec7e017130ddc5c1b5466340470f4900)
1 /* leon_smp.c: Sparc-Leon SMP support.
2  *
3  * based on sun4m_smp.c
4  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
5  * Copyright (C) 2009 Daniel Hellstrom (daniel@gaisler.com) Aeroflex Gaisler AB
6  * Copyright (C) 2009 Konrad Eisele (konrad@gaisler.com) Aeroflex Gaisler AB
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/interrupt.h>
16 #include <linux/kernel_stat.h>
17 #include <linux/init.h>
18 #include <linux/spinlock.h>
19 #include <linux/mm.h>
20 #include <linux/swap.h>
21 #include <linux/profile.h>
22 #include <linux/pm.h>
23 #include <linux/delay.h>
24 #include <linux/gfp.h>
25 
26 #include <asm/cacheflush.h>
27 #include <asm/tlbflush.h>
28 
29 #include <asm/ptrace.h>
30 #include <asm/atomic.h>
31 #include <asm/irq_regs.h>
32 
33 #include <asm/delay.h>
34 #include <asm/irq.h>
35 #include <asm/page.h>
36 #include <asm/pgalloc.h>
37 #include <asm/pgtable.h>
38 #include <asm/oplib.h>
39 #include <asm/cpudata.h>
40 #include <asm/asi.h>
41 #include <asm/leon.h>
42 #include <asm/leon_amba.h>
43 
44 #include "kernel.h"
45 
46 #ifdef CONFIG_SPARC_LEON
47 
48 #include "irq.h"
49 
50 extern ctxd_t *srmmu_ctx_table_phys;
51 static int smp_processors_ready;
52 extern volatile unsigned long cpu_callin_map[NR_CPUS];
53 extern unsigned char boot_cpu_id;
54 extern cpumask_t smp_commenced_mask;
55 void __init leon_configure_cache_smp(void);
56 
57 static inline unsigned long do_swap(volatile unsigned long *ptr,
58 				    unsigned long val)
59 {
60 	__asm__ __volatile__("swapa [%2] %3, %0\n\t" : "=&r"(val)
61 			     : "0"(val), "r"(ptr), "i"(ASI_LEON_DCACHE_MISS)
62 			     : "memory");
63 	return val;
64 }
65 
66 static void smp_setup_percpu_timer(void);
67 
68 void __cpuinit leon_callin(void)
69 {
70 	int cpuid = hard_smpleon_processor_id();
71 
72 	local_flush_cache_all();
73 	local_flush_tlb_all();
74 	leon_configure_cache_smp();
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 	 * Allow master to continue.
91 	 */
92 	do_swap(&cpu_callin_map[cpuid], 1);
93 
94 	local_flush_cache_all();
95 	local_flush_tlb_all();
96 
97 	cpu_probe();
98 
99 	/* Fix idle thread fields. */
100 	__asm__ __volatile__("ld [%0], %%g6\n\t" : : "r"(&current_set[cpuid])
101 			     : "memory" /* paranoid */);
102 
103 	/* Attach to the address space of init_task. */
104 	atomic_inc(&init_mm.mm_count);
105 	current->active_mm = &init_mm;
106 
107 	while (!cpu_isset(cpuid, smp_commenced_mask))
108 		mb();
109 
110 	local_irq_enable();
111 	cpu_set(cpuid, cpu_online_map);
112 }
113 
114 /*
115  *	Cycle through the processors asking the PROM to start each one.
116  */
117 
118 extern struct linux_prom_registers smp_penguin_ctable;
119 
120 void __init leon_configure_cache_smp(void)
121 {
122 	unsigned long cfg = sparc_leon3_get_dcachecfg();
123 	int me = smp_processor_id();
124 
125 	if (ASI_LEON3_SYSCTRL_CFG_SSIZE(cfg) > 4) {
126 		printk(KERN_INFO "Note: SMP with snooping only works on 4k cache, found %dk(0x%x) on cpu %d, disabling caches\n",
127 		     (unsigned int)ASI_LEON3_SYSCTRL_CFG_SSIZE(cfg),
128 		     (unsigned int)cfg, (unsigned int)me);
129 		sparc_leon3_disable_cache();
130 	} else {
131 		if (cfg & ASI_LEON3_SYSCTRL_CFG_SNOOPING) {
132 			sparc_leon3_enable_snooping();
133 		} else {
134 			printk(KERN_INFO "Note: You have to enable snooping in the vhdl model cpu %d, disabling caches\n",
135 			     me);
136 			sparc_leon3_disable_cache();
137 		}
138 	}
139 
140 	local_flush_cache_all();
141 	local_flush_tlb_all();
142 }
143 
144 void leon_smp_setbroadcast(unsigned int mask)
145 {
146 	int broadcast =
147 	    ((LEON3_BYPASS_LOAD_PA(&(leon3_irqctrl_regs->mpstatus)) >>
148 	      LEON3_IRQMPSTATUS_BROADCAST) & 1);
149 	if (!broadcast) {
150 		prom_printf("######## !!!! The irqmp-ctrl must have broadcast enabled, smp wont work !!!!! ####### nr cpus: %d\n",
151 		     leon_smp_nrcpus());
152 		if (leon_smp_nrcpus() > 1) {
153 			BUG();
154 		} else {
155 			prom_printf("continue anyway\n");
156 			return;
157 		}
158 	}
159 	LEON_BYPASS_STORE_PA(&(leon3_irqctrl_regs->mpbroadcast), mask);
160 }
161 
162 unsigned int leon_smp_getbroadcast(void)
163 {
164 	unsigned int mask;
165 	mask = LEON_BYPASS_LOAD_PA(&(leon3_irqctrl_regs->mpbroadcast));
166 	return mask;
167 }
168 
169 int leon_smp_nrcpus(void)
170 {
171 	int nrcpu =
172 	    ((LEON3_BYPASS_LOAD_PA(&(leon3_irqctrl_regs->mpstatus)) >>
173 	      LEON3_IRQMPSTATUS_CPUNR) & 0xf) + 1;
174 	return nrcpu;
175 }
176 
177 void __init leon_boot_cpus(void)
178 {
179 	int nrcpu = leon_smp_nrcpus();
180 	int me = smp_processor_id();
181 
182 	printk(KERN_INFO "%d:(%d:%d) cpus mpirq at 0x%x\n", (unsigned int)me,
183 	       (unsigned int)nrcpu, (unsigned int)NR_CPUS,
184 	       (unsigned int)&(leon3_irqctrl_regs->mpstatus));
185 
186 	leon_enable_irq_cpu(LEON3_IRQ_CROSS_CALL, me);
187 	leon_enable_irq_cpu(LEON3_IRQ_TICKER, me);
188 	leon_enable_irq_cpu(LEON3_IRQ_RESCHEDULE, me);
189 
190 	leon_smp_setbroadcast(1 << LEON3_IRQ_TICKER);
191 
192 	leon_configure_cache_smp();
193 	smp_setup_percpu_timer();
194 	local_flush_cache_all();
195 
196 }
197 
198 int __cpuinit leon_boot_one_cpu(int i)
199 {
200 
201 	struct task_struct *p;
202 	int timeout;
203 
204 	/* Cook up an idler for this guy. */
205 	p = fork_idle(i);
206 
207 	current_set[i] = task_thread_info(p);
208 
209 	/* See trampoline.S:leon_smp_cpu_startup for details...
210 	 * Initialize the contexts table
211 	 * Since the call to prom_startcpu() trashes the structure,
212 	 * we need to re-initialize it for each cpu
213 	 */
214 	smp_penguin_ctable.which_io = 0;
215 	smp_penguin_ctable.phys_addr = (unsigned int)srmmu_ctx_table_phys;
216 	smp_penguin_ctable.reg_size = 0;
217 
218 	/* whirrr, whirrr, whirrrrrrrrr... */
219 	printk(KERN_INFO "Starting CPU %d : (irqmp: 0x%x)\n", (unsigned int)i,
220 	       (unsigned int)&leon3_irqctrl_regs->mpstatus);
221 	local_flush_cache_all();
222 
223 	LEON_BYPASS_STORE_PA(&(leon3_irqctrl_regs->mpstatus), 1 << i);
224 
225 	/* wheee... it's going... */
226 	for (timeout = 0; timeout < 10000; timeout++) {
227 		if (cpu_callin_map[i])
228 			break;
229 		udelay(200);
230 	}
231 	printk(KERN_INFO "Started CPU %d\n", (unsigned int)i);
232 
233 	if (!(cpu_callin_map[i])) {
234 		printk(KERN_ERR "Processor %d is stuck.\n", i);
235 		return -ENODEV;
236 	} else {
237 		leon_enable_irq_cpu(LEON3_IRQ_CROSS_CALL, i);
238 		leon_enable_irq_cpu(LEON3_IRQ_TICKER, i);
239 		leon_enable_irq_cpu(LEON3_IRQ_RESCHEDULE, i);
240 	}
241 
242 	local_flush_cache_all();
243 	return 0;
244 }
245 
246 void __init leon_smp_done(void)
247 {
248 
249 	int i, first;
250 	int *prev;
251 
252 	/* setup cpu list for irq rotation */
253 	first = 0;
254 	prev = &first;
255 	for (i = 0; i < NR_CPUS; i++) {
256 		if (cpu_online(i)) {
257 			*prev = i;
258 			prev = &cpu_data(i).next;
259 		}
260 	}
261 	*prev = first;
262 	local_flush_cache_all();
263 
264 	/* Free unneeded trap tables */
265 	if (!cpu_isset(1, cpu_present_map)) {
266 		ClearPageReserved(virt_to_page(&trapbase_cpu1));
267 		init_page_count(virt_to_page(&trapbase_cpu1));
268 		free_page((unsigned long)&trapbase_cpu1);
269 		totalram_pages++;
270 		num_physpages++;
271 	}
272 	if (!cpu_isset(2, cpu_present_map)) {
273 		ClearPageReserved(virt_to_page(&trapbase_cpu2));
274 		init_page_count(virt_to_page(&trapbase_cpu2));
275 		free_page((unsigned long)&trapbase_cpu2);
276 		totalram_pages++;
277 		num_physpages++;
278 	}
279 	if (!cpu_isset(3, cpu_present_map)) {
280 		ClearPageReserved(virt_to_page(&trapbase_cpu3));
281 		init_page_count(virt_to_page(&trapbase_cpu3));
282 		free_page((unsigned long)&trapbase_cpu3);
283 		totalram_pages++;
284 		num_physpages++;
285 	}
286 	/* Ok, they are spinning and ready to go. */
287 	smp_processors_ready = 1;
288 
289 }
290 
291 void leon_irq_rotate(int cpu)
292 {
293 }
294 
295 static struct smp_funcall {
296 	smpfunc_t func;
297 	unsigned long arg1;
298 	unsigned long arg2;
299 	unsigned long arg3;
300 	unsigned long arg4;
301 	unsigned long arg5;
302 	unsigned long processors_in[NR_CPUS];	/* Set when ipi entered. */
303 	unsigned long processors_out[NR_CPUS];	/* Set when ipi exited. */
304 } ccall_info;
305 
306 static DEFINE_SPINLOCK(cross_call_lock);
307 
308 /* Cross calls must be serialized, at least currently. */
309 static void leon_cross_call(smpfunc_t func, cpumask_t mask, unsigned long arg1,
310 			    unsigned long arg2, unsigned long arg3,
311 			    unsigned long arg4)
312 {
313 	if (smp_processors_ready) {
314 		register int high = NR_CPUS - 1;
315 		unsigned long flags;
316 
317 		spin_lock_irqsave(&cross_call_lock, flags);
318 
319 		{
320 			/* If you make changes here, make sure gcc generates proper code... */
321 			register smpfunc_t f asm("i0") = func;
322 			register unsigned long a1 asm("i1") = arg1;
323 			register unsigned long a2 asm("i2") = arg2;
324 			register unsigned long a3 asm("i3") = arg3;
325 			register unsigned long a4 asm("i4") = arg4;
326 			register unsigned long a5 asm("i5") = 0;
327 
328 			__asm__ __volatile__("std %0, [%6]\n\t"
329 					     "std %2, [%6 + 8]\n\t"
330 					     "std %4, [%6 + 16]\n\t" : :
331 					     "r"(f), "r"(a1), "r"(a2), "r"(a3),
332 					     "r"(a4), "r"(a5),
333 					     "r"(&ccall_info.func));
334 		}
335 
336 		/* Init receive/complete mapping, plus fire the IPI's off. */
337 		{
338 			register int i;
339 
340 			cpu_clear(smp_processor_id(), mask);
341 			cpus_and(mask, cpu_online_map, mask);
342 			for (i = 0; i <= high; i++) {
343 				if (cpu_isset(i, mask)) {
344 					ccall_info.processors_in[i] = 0;
345 					ccall_info.processors_out[i] = 0;
346 					set_cpu_int(i, LEON3_IRQ_CROSS_CALL);
347 
348 				}
349 			}
350 		}
351 
352 		{
353 			register int i;
354 
355 			i = 0;
356 			do {
357 				if (!cpu_isset(i, mask))
358 					continue;
359 
360 				while (!ccall_info.processors_in[i])
361 					barrier();
362 			} while (++i <= high);
363 
364 			i = 0;
365 			do {
366 				if (!cpu_isset(i, mask))
367 					continue;
368 
369 				while (!ccall_info.processors_out[i])
370 					barrier();
371 			} while (++i <= high);
372 		}
373 
374 		spin_unlock_irqrestore(&cross_call_lock, flags);
375 	}
376 }
377 
378 /* Running cross calls. */
379 void leon_cross_call_irq(void)
380 {
381 	int i = smp_processor_id();
382 
383 	ccall_info.processors_in[i] = 1;
384 	ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
385 			ccall_info.arg4, ccall_info.arg5);
386 	ccall_info.processors_out[i] = 1;
387 }
388 
389 void leon_percpu_timer_interrupt(struct pt_regs *regs)
390 {
391 	struct pt_regs *old_regs;
392 	int cpu = smp_processor_id();
393 
394 	old_regs = set_irq_regs(regs);
395 
396 	leon_clear_profile_irq(cpu);
397 
398 	profile_tick(CPU_PROFILING);
399 
400 	if (!--prof_counter(cpu)) {
401 		int user = user_mode(regs);
402 
403 		irq_enter();
404 		update_process_times(user);
405 		irq_exit();
406 
407 		prof_counter(cpu) = prof_multiplier(cpu);
408 	}
409 	set_irq_regs(old_regs);
410 }
411 
412 static void __init smp_setup_percpu_timer(void)
413 {
414 	int cpu = smp_processor_id();
415 
416 	prof_counter(cpu) = prof_multiplier(cpu) = 1;
417 }
418 
419 void __init leon_blackbox_id(unsigned *addr)
420 {
421 	int rd = *addr & 0x3e000000;
422 	int rs1 = rd >> 11;
423 
424 	/* patch places where ___b_hard_smp_processor_id appears */
425 	addr[0] = 0x81444000 | rd;	/* rd %asr17, reg */
426 	addr[1] = 0x8130201c | rd | rs1;	/* srl reg, 0x1c, reg */
427 	addr[2] = 0x01000000;	/* nop */
428 }
429 
430 void __init leon_blackbox_current(unsigned *addr)
431 {
432 	int rd = *addr & 0x3e000000;
433 	int rs1 = rd >> 11;
434 
435 	/* patch LOAD_CURRENT macro where ___b_load_current appears */
436 	addr[0] = 0x81444000 | rd;	/* rd %asr17, reg */
437 	addr[2] = 0x8130201c | rd | rs1;	/* srl reg, 0x1c, reg */
438 	addr[4] = 0x81282002 | rd | rs1;	/* sll reg, 0x2, reg */
439 
440 }
441 
442 void __init leon_init_smp(void)
443 {
444 	/* Patch ipi15 trap table */
445 	t_nmi[1] = t_nmi[1] + (linux_trap_ipi15_leon - linux_trap_ipi15_sun4m);
446 
447 	BTFIXUPSET_BLACKBOX(hard_smp_processor_id, leon_blackbox_id);
448 	BTFIXUPSET_BLACKBOX(load_current, leon_blackbox_current);
449 	BTFIXUPSET_CALL(smp_cross_call, leon_cross_call, BTFIXUPCALL_NORM);
450 	BTFIXUPSET_CALL(__hard_smp_processor_id, __leon_processor_id,
451 			BTFIXUPCALL_NORM);
452 }
453 
454 #endif /* CONFIG_SPARC_LEON */
455