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(&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; 107 108 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(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(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[0])); 249 } 250 if (!cpu_present(2)) { 251 free_reserved_page(virt_to_page(&trapbase_cpu2[0])); 252 } 253 if (!cpu_present(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("/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 } 302 303 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 } 309 310 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 } 320 321 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 } 331 332 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 } 342 343 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(), &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. */ 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