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 | |
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 | |
71 | void leon_cpu_pre_starting(void *arg) |
72 | { |
73 | leon_configure_cache_smp(); |
74 | } |
75 | |
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(ptr: &cpu_callin_map[cpuid], val: 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(mm: &init_mm); |
96 | current->active_mm = &init_mm; |
97 | |
98 | while (!cpumask_test_cpu(cpu: cpuid, cpumask: &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 | |
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 | |
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 | |
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 | |
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(mask: 1 << LEON3_IRQ_TICKER); |
175 | |
176 | leon_configure_cache_smp(); |
177 | local_ops->cache_all(); |
178 | |
179 | } |
180 | |
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 | |
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(cpu: 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(cpu: 1)) { |
248 | free_reserved_page(virt_to_page(&trapbase_cpu1[0])); |
249 | } |
250 | if (!cpu_present(cpu: 2)) { |
251 | free_reserved_page(virt_to_page(&trapbase_cpu2[0])); |
252 | } |
253 | if (!cpu_present(cpu: 3)) { |
254 | free_reserved_page(virt_to_page(&trapbase_cpu3[0])); |
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 | */ |
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(path: "/ambapp0" ); |
283 | if (rootnp) { |
284 | pp = of_find_property(np: rootnp, name: "ipi_num" , lenp: &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 | |
303 | static void leon_send_ipi(int cpu, int level) |
304 | { |
305 | unsigned long mask; |
306 | mask = leon_get_irqmask(irq: level); |
307 | LEON3_BYPASS_STORE_PA(&leon3_irqctrl_regs->force[cpu], mask); |
308 | } |
309 | |
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, level: leon_ipi_irq); |
319 | } |
320 | |
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, level: leon_ipi_irq); |
330 | } |
331 | |
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, level: leon_ipi_irq); |
341 | } |
342 | |
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. */ |
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(), dstp: &mask); |
407 | cpumask_and(dstp: &mask, cpu_online_mask, src2p: &mask); |
408 | for (i = 0; i <= high; i++) { |
409 | if (cpumask_test_cpu(cpu: i, cpumask: &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(cpu: i, cpumask: &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(cpu: i, cpumask: &mask)) |
433 | continue; |
434 | |
435 | while (!ccall_info.processors_out[i]) |
436 | barrier(); |
437 | } while (++i <= high); |
438 | } |
439 | |
440 | spin_unlock_irqrestore(lock: &cross_call_lock, flags); |
441 | } |
442 | } |
443 | |
444 | /* Running cross calls. */ |
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 | |
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 | |