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