1 // SPDX-License-Identifier: GPL-2.0
2 /* leon_smp.c: Sparc-Leon SMP support.
3 *
4 * based on sun4m_smp.c
5 * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
6 * Copyright (C) 2009 Daniel Hellstrom (daniel@gaisler.com) Aeroflex Gaisler AB
7 * Copyright (C) 2009 Konrad Eisele (konrad@gaisler.com) Aeroflex Gaisler AB
8 */
9
10 #include <asm/head.h>
11
12 #include <linux/kernel.h>
13 #include <linux/sched/mm.h>
14 #include <linux/threads.h>
15 #include <linux/smp.h>
16 #include <linux/interrupt.h>
17 #include <linux/kernel_stat.h>
18 #include <linux/of.h>
19 #include <linux/init.h>
20 #include <linux/spinlock.h>
21 #include <linux/mm.h>
22 #include <linux/swap.h>
23 #include <linux/profile.h>
24 #include <linux/pm.h>
25 #include <linux/delay.h>
26 #include <linux/gfp.h>
27 #include <linux/cpu.h>
28 #include <linux/clockchips.h>
29
30 #include <asm/cacheflush.h>
31 #include <asm/tlbflush.h>
32
33 #include <asm/ptrace.h>
34 #include <linux/atomic.h>
35 #include <asm/irq_regs.h>
36 #include <asm/traps.h>
37
38 #include <asm/delay.h>
39 #include <asm/irq.h>
40 #include <asm/page.h>
41 #include <asm/oplib.h>
42 #include <asm/cpudata.h>
43 #include <asm/asi.h>
44 #include <asm/leon.h>
45 #include <asm/leon_amba.h>
46 #include <asm/timer.h>
47
48 #include "kernel.h"
49
50 #include "irq.h"
51
52 extern ctxd_t *srmmu_ctx_table_phys;
53 static int smp_processors_ready;
54 extern volatile unsigned long cpu_callin_map[NR_CPUS];
55 extern cpumask_t smp_commenced_mask;
56 void leon_configure_cache_smp(void);
57 static void leon_ipi_init(void);
58
59 /* IRQ number of LEON IPIs */
60 int leon_ipi_irq = LEON3_IRQ_IPI_DEFAULT;
61
do_swap(volatile unsigned long * ptr,unsigned long val)62 static inline unsigned long do_swap(volatile unsigned long *ptr,
63 unsigned long val)
64 {
65 __asm__ __volatile__("swapa [%2] %3, %0\n\t" : "=&r"(val)
66 : "0"(val), "r"(ptr), "i"(ASI_LEON_DCACHE_MISS)
67 : "memory");
68 return val;
69 }
70
leon_cpu_pre_starting(void * arg)71 void leon_cpu_pre_starting(void *arg)
72 {
73 leon_configure_cache_smp();
74 }
75
leon_cpu_pre_online(void * arg)76 void leon_cpu_pre_online(void *arg)
77 {
78 int cpuid = hard_smp_processor_id();
79
80 /* Allow master to continue. The master will then give us the
81 * go-ahead by setting the smp_commenced_mask and will wait without
82 * timeouts until our setup is completed fully (signified by
83 * our bit being set in the cpu_online_mask).
84 */
85 do_swap(&cpu_callin_map[cpuid], 1);
86
87 local_ops->cache_all();
88 local_ops->tlb_all();
89
90 /* Fix idle thread fields. */
91 __asm__ __volatile__("ld [%0], %%g6\n\t" : : "r"(¤t_set[cpuid])
92 : "memory" /* paranoid */);
93
94 /* Attach to the address space of init_task. */
95 mmgrab(&init_mm);
96 current->active_mm = &init_mm;
97
98 while (!cpumask_test_cpu(cpuid, &smp_commenced_mask))
99 mb();
100 }
101
102 /*
103 * Cycle through the processors asking the PROM to start each one.
104 */
105
106 extern struct linux_prom_registers smp_penguin_ctable;
107
leon_configure_cache_smp(void)108 void leon_configure_cache_smp(void)
109 {
110 unsigned long cfg = sparc_leon3_get_dcachecfg();
111 int me = smp_processor_id();
112
113 if (ASI_LEON3_SYSCTRL_CFG_SSIZE(cfg) > 4) {
114 printk(KERN_INFO "Note: SMP with snooping only works on 4k cache, found %dk(0x%x) on cpu %d, disabling caches\n",
115 (unsigned int)ASI_LEON3_SYSCTRL_CFG_SSIZE(cfg),
116 (unsigned int)cfg, (unsigned int)me);
117 sparc_leon3_disable_cache();
118 } else {
119 if (cfg & ASI_LEON3_SYSCTRL_CFG_SNOOPING) {
120 sparc_leon3_enable_snooping();
121 } else {
122 printk(KERN_INFO "Note: You have to enable snooping in the vhdl model cpu %d, disabling caches\n",
123 me);
124 sparc_leon3_disable_cache();
125 }
126 }
127
128 local_ops->cache_all();
129 local_ops->tlb_all();
130 }
131
leon_smp_setbroadcast(unsigned int mask)132 static void leon_smp_setbroadcast(unsigned int mask)
133 {
134 int broadcast =
135 ((LEON3_BYPASS_LOAD_PA(&(leon3_irqctrl_regs->mpstatus)) >>
136 LEON3_IRQMPSTATUS_BROADCAST) & 1);
137 if (!broadcast) {
138 prom_printf("######## !!!! The irqmp-ctrl must have broadcast enabled, smp wont work !!!!! ####### nr cpus: %d\n",
139 leon_smp_nrcpus());
140 if (leon_smp_nrcpus() > 1) {
141 BUG();
142 } else {
143 prom_printf("continue anyway\n");
144 return;
145 }
146 }
147 LEON_BYPASS_STORE_PA(&(leon3_irqctrl_regs->mpbroadcast), mask);
148 }
149
leon_smp_nrcpus(void)150 int leon_smp_nrcpus(void)
151 {
152 int nrcpu =
153 ((LEON3_BYPASS_LOAD_PA(&(leon3_irqctrl_regs->mpstatus)) >>
154 LEON3_IRQMPSTATUS_CPUNR) & 0xf) + 1;
155 return nrcpu;
156 }
157
leon_boot_cpus(void)158 void __init leon_boot_cpus(void)
159 {
160 int nrcpu = leon_smp_nrcpus();
161 int me = smp_processor_id();
162
163 /* Setup IPI */
164 leon_ipi_init();
165
166 printk(KERN_INFO "%d:(%d:%d) cpus mpirq at 0x%x\n", (unsigned int)me,
167 (unsigned int)nrcpu, (unsigned int)NR_CPUS,
168 (unsigned int)&(leon3_irqctrl_regs->mpstatus));
169
170 leon_enable_irq_cpu(LEON3_IRQ_CROSS_CALL, me);
171 leon_enable_irq_cpu(LEON3_IRQ_TICKER, me);
172 leon_enable_irq_cpu(leon_ipi_irq, me);
173
174 leon_smp_setbroadcast(1 << LEON3_IRQ_TICKER);
175
176 leon_configure_cache_smp();
177 local_ops->cache_all();
178
179 }
180
leon_boot_one_cpu(int i,struct task_struct * idle)181 int leon_boot_one_cpu(int i, struct task_struct *idle)
182 {
183 int timeout;
184
185 current_set[i] = task_thread_info(idle);
186
187 /* See trampoline.S:leon_smp_cpu_startup for details...
188 * Initialize the contexts table
189 * Since the call to prom_startcpu() trashes the structure,
190 * we need to re-initialize it for each cpu
191 */
192 smp_penguin_ctable.which_io = 0;
193 smp_penguin_ctable.phys_addr = (unsigned int)srmmu_ctx_table_phys;
194 smp_penguin_ctable.reg_size = 0;
195
196 /* whirrr, whirrr, whirrrrrrrrr... */
197 printk(KERN_INFO "Starting CPU %d : (irqmp: 0x%x)\n", (unsigned int)i,
198 (unsigned int)&leon3_irqctrl_regs->mpstatus);
199 local_ops->cache_all();
200
201 /* Make sure all IRQs are of from the start for this new CPU */
202 LEON_BYPASS_STORE_PA(&leon3_irqctrl_regs->mask[i], 0);
203
204 /* Wake one CPU */
205 LEON_BYPASS_STORE_PA(&(leon3_irqctrl_regs->mpstatus), 1 << i);
206
207 /* wheee... it's going... */
208 for (timeout = 0; timeout < 10000; timeout++) {
209 if (cpu_callin_map[i])
210 break;
211 udelay(200);
212 }
213 printk(KERN_INFO "Started CPU %d\n", (unsigned int)i);
214
215 if (!(cpu_callin_map[i])) {
216 printk(KERN_ERR "Processor %d is stuck.\n", i);
217 return -ENODEV;
218 } else {
219 leon_enable_irq_cpu(LEON3_IRQ_CROSS_CALL, i);
220 leon_enable_irq_cpu(LEON3_IRQ_TICKER, i);
221 leon_enable_irq_cpu(leon_ipi_irq, i);
222 }
223
224 local_ops->cache_all();
225 return 0;
226 }
227
leon_smp_done(void)228 void __init leon_smp_done(void)
229 {
230
231 int i, first;
232 int *prev;
233
234 /* setup cpu list for irq rotation */
235 first = 0;
236 prev = &first;
237 for (i = 0; i < NR_CPUS; i++) {
238 if (cpu_online(i)) {
239 *prev = i;
240 prev = &cpu_data(i).next;
241 }
242 }
243 *prev = first;
244 local_ops->cache_all();
245
246 /* Free unneeded trap tables */
247 if (!cpu_present(1)) {
248 free_reserved_page(virt_to_page(&trapbase_cpu1));
249 }
250 if (!cpu_present(2)) {
251 free_reserved_page(virt_to_page(&trapbase_cpu2));
252 }
253 if (!cpu_present(3)) {
254 free_reserved_page(virt_to_page(&trapbase_cpu3));
255 }
256 /* Ok, they are spinning and ready to go. */
257 smp_processors_ready = 1;
258
259 }
260
261 struct leon_ipi_work {
262 int single;
263 int msk;
264 int resched;
265 };
266
267 static DEFINE_PER_CPU_SHARED_ALIGNED(struct leon_ipi_work, leon_ipi_work);
268
269 /* Initialize IPIs on the LEON, in order to save IRQ resources only one IRQ
270 * is used for all three types of IPIs.
271 */
leon_ipi_init(void)272 static void __init leon_ipi_init(void)
273 {
274 int cpu, len;
275 struct leon_ipi_work *work;
276 struct property *pp;
277 struct device_node *rootnp;
278 struct tt_entry *trap_table;
279 unsigned long flags;
280
281 /* Find IPI IRQ or stick with default value */
282 rootnp = of_find_node_by_path("/ambapp0");
283 if (rootnp) {
284 pp = of_find_property(rootnp, "ipi_num", &len);
285 if (pp && (*(int *)pp->value))
286 leon_ipi_irq = *(int *)pp->value;
287 }
288 printk(KERN_INFO "leon: SMP IPIs at IRQ %d\n", leon_ipi_irq);
289
290 /* Adjust so that we jump directly to smpleon_ipi */
291 local_irq_save(flags);
292 trap_table = &sparc_ttable[SP_TRAP_IRQ1 + (leon_ipi_irq - 1)];
293 trap_table->inst_three += smpleon_ipi - real_irq_entry;
294 local_ops->cache_all();
295 local_irq_restore(flags);
296
297 for_each_possible_cpu(cpu) {
298 work = &per_cpu(leon_ipi_work, cpu);
299 work->single = work->msk = work->resched = 0;
300 }
301 }
302
leon_send_ipi(int cpu,int level)303 static void leon_send_ipi(int cpu, int level)
304 {
305 unsigned long mask;
306 mask = leon_get_irqmask(level);
307 LEON3_BYPASS_STORE_PA(&leon3_irqctrl_regs->force[cpu], mask);
308 }
309
leon_ipi_single(int cpu)310 static void leon_ipi_single(int cpu)
311 {
312 struct leon_ipi_work *work = &per_cpu(leon_ipi_work, cpu);
313
314 /* Mark work */
315 work->single = 1;
316
317 /* Generate IRQ on the CPU */
318 leon_send_ipi(cpu, leon_ipi_irq);
319 }
320
leon_ipi_mask_one(int cpu)321 static void leon_ipi_mask_one(int cpu)
322 {
323 struct leon_ipi_work *work = &per_cpu(leon_ipi_work, cpu);
324
325 /* Mark work */
326 work->msk = 1;
327
328 /* Generate IRQ on the CPU */
329 leon_send_ipi(cpu, leon_ipi_irq);
330 }
331
leon_ipi_resched(int cpu)332 static void leon_ipi_resched(int cpu)
333 {
334 struct leon_ipi_work *work = &per_cpu(leon_ipi_work, cpu);
335
336 /* Mark work */
337 work->resched = 1;
338
339 /* Generate IRQ on the CPU (any IRQ will cause resched) */
340 leon_send_ipi(cpu, leon_ipi_irq);
341 }
342
leonsmp_ipi_interrupt(void)343 void leonsmp_ipi_interrupt(void)
344 {
345 struct leon_ipi_work *work = this_cpu_ptr(&leon_ipi_work);
346
347 if (work->single) {
348 work->single = 0;
349 smp_call_function_single_interrupt();
350 }
351 if (work->msk) {
352 work->msk = 0;
353 smp_call_function_interrupt();
354 }
355 if (work->resched) {
356 work->resched = 0;
357 smp_resched_interrupt();
358 }
359 }
360
361 static struct smp_funcall {
362 void *func;
363 unsigned long arg1;
364 unsigned long arg2;
365 unsigned long arg3;
366 unsigned long arg4;
367 unsigned long arg5;
368 unsigned long processors_in[NR_CPUS]; /* Set when ipi entered. */
369 unsigned long processors_out[NR_CPUS]; /* Set when ipi exited. */
370 } ccall_info __attribute__((aligned(8)));
371
372 static DEFINE_SPINLOCK(cross_call_lock);
373
374 /* Cross calls must be serialized, at least currently. */
leon_cross_call(void * func,cpumask_t mask,unsigned long arg1,unsigned long arg2,unsigned long arg3,unsigned long arg4)375 static void leon_cross_call(void *func, cpumask_t mask, unsigned long arg1,
376 unsigned long arg2, unsigned long arg3,
377 unsigned long arg4)
378 {
379 if (smp_processors_ready) {
380 register int high = NR_CPUS - 1;
381 unsigned long flags;
382
383 spin_lock_irqsave(&cross_call_lock, flags);
384
385 {
386 /* If you make changes here, make sure gcc generates proper code... */
387 register void *f asm("i0") = func;
388 register unsigned long a1 asm("i1") = arg1;
389 register unsigned long a2 asm("i2") = arg2;
390 register unsigned long a3 asm("i3") = arg3;
391 register unsigned long a4 asm("i4") = arg4;
392 register unsigned long a5 asm("i5") = 0;
393
394 __asm__ __volatile__("std %0, [%6]\n\t"
395 "std %2, [%6 + 8]\n\t"
396 "std %4, [%6 + 16]\n\t" : :
397 "r"(f), "r"(a1), "r"(a2), "r"(a3),
398 "r"(a4), "r"(a5),
399 "r"(&ccall_info.func));
400 }
401
402 /* Init receive/complete mapping, plus fire the IPI's off. */
403 {
404 register int i;
405
406 cpumask_clear_cpu(smp_processor_id(), &mask);
407 cpumask_and(&mask, cpu_online_mask, &mask);
408 for (i = 0; i <= high; i++) {
409 if (cpumask_test_cpu(i, &mask)) {
410 ccall_info.processors_in[i] = 0;
411 ccall_info.processors_out[i] = 0;
412 leon_send_ipi(i, LEON3_IRQ_CROSS_CALL);
413
414 }
415 }
416 }
417
418 {
419 register int i;
420
421 i = 0;
422 do {
423 if (!cpumask_test_cpu(i, &mask))
424 continue;
425
426 while (!ccall_info.processors_in[i])
427 barrier();
428 } while (++i <= high);
429
430 i = 0;
431 do {
432 if (!cpumask_test_cpu(i, &mask))
433 continue;
434
435 while (!ccall_info.processors_out[i])
436 barrier();
437 } while (++i <= high);
438 }
439
440 spin_unlock_irqrestore(&cross_call_lock, flags);
441 }
442 }
443
444 /* Running cross calls. */
leon_cross_call_irq(void)445 void leon_cross_call_irq(void)
446 {
447 void (*func)(unsigned long, unsigned long, unsigned long, unsigned long,
448 unsigned long) = ccall_info.func;
449 int i = smp_processor_id();
450
451 ccall_info.processors_in[i] = 1;
452 func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3, ccall_info.arg4,
453 ccall_info.arg5);
454 ccall_info.processors_out[i] = 1;
455 }
456
457 static const struct sparc32_ipi_ops leon_ipi_ops = {
458 .cross_call = leon_cross_call,
459 .resched = leon_ipi_resched,
460 .single = leon_ipi_single,
461 .mask_one = leon_ipi_mask_one,
462 };
463
leon_init_smp(void)464 void __init leon_init_smp(void)
465 {
466 /* Patch ipi15 trap table */
467 t_nmi[1] = t_nmi[1] + (linux_trap_ipi15_leon - linux_trap_ipi15_sun4m);
468
469 sparc32_ipi_ops = &leon_ipi_ops;
470 }
471