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