1 // SPDX-License-Identifier: GPL-2.0 2 /* smp.c: Sparc SMP support. 3 * 4 * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu) 5 * Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz) 6 * Copyright (C) 2004 Keith M Wesolowski (wesolows@foobazco.org) 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/init.h> 18 #include <linux/spinlock.h> 19 #include <linux/mm.h> 20 #include <linux/fs.h> 21 #include <linux/seq_file.h> 22 #include <linux/cache.h> 23 #include <linux/delay.h> 24 #include <linux/profile.h> 25 #include <linux/cpu.h> 26 27 #include <asm/ptrace.h> 28 #include <linux/atomic.h> 29 30 #include <asm/irq.h> 31 #include <asm/page.h> 32 #include <asm/pgalloc.h> 33 #include <asm/oplib.h> 34 #include <asm/cacheflush.h> 35 #include <asm/tlbflush.h> 36 #include <asm/cpudata.h> 37 #include <asm/timer.h> 38 #include <asm/leon.h> 39 40 #include "kernel.h" 41 #include "irq.h" 42 43 volatile unsigned long cpu_callin_map[NR_CPUS] = {0,}; 44 45 cpumask_t smp_commenced_mask = CPU_MASK_NONE; 46 47 const struct sparc32_ipi_ops *sparc32_ipi_ops; 48 49 /* The only guaranteed locking primitive available on all Sparc 50 * processors is 'ldstub [%reg + immediate], %dest_reg' which atomically 51 * places the current byte at the effective address into dest_reg and 52 * places 0xff there afterwards. Pretty lame locking primitive 53 * compared to the Alpha and the Intel no? Most Sparcs have 'swap' 54 * instruction which is much better... 55 */ 56 57 void smp_store_cpu_info(int id) 58 { 59 int cpu_node; 60 int mid; 61 62 cpu_data(id).udelay_val = loops_per_jiffy; 63 64 cpu_find_by_mid(id, &cpu_node); 65 cpu_data(id).clock_tick = prom_getintdefault(cpu_node, 66 "clock-frequency", 0); 67 cpu_data(id).prom_node = cpu_node; 68 mid = cpu_get_hwmid(cpu_node); 69 70 if (mid < 0) { 71 printk(KERN_NOTICE "No MID found for CPU%d at node 0x%08x", id, cpu_node); 72 mid = 0; 73 } 74 cpu_data(id).mid = mid; 75 } 76 77 void __init smp_cpus_done(unsigned int max_cpus) 78 { 79 unsigned long bogosum = 0; 80 int cpu, num = 0; 81 82 for_each_online_cpu(cpu) { 83 num++; 84 bogosum += cpu_data(cpu).udelay_val; 85 } 86 87 printk("Total of %d processors activated (%lu.%02lu BogoMIPS).\n", 88 num, bogosum/(500000/HZ), 89 (bogosum/(5000/HZ))%100); 90 91 switch(sparc_cpu_model) { 92 case sun4m: 93 smp4m_smp_done(); 94 break; 95 case sun4d: 96 smp4d_smp_done(); 97 break; 98 case sparc_leon: 99 leon_smp_done(); 100 break; 101 case sun4e: 102 printk("SUN4E\n"); 103 BUG(); 104 break; 105 case sun4u: 106 printk("SUN4U\n"); 107 BUG(); 108 break; 109 default: 110 printk("UNKNOWN!\n"); 111 BUG(); 112 break; 113 } 114 } 115 116 void cpu_panic(void) 117 { 118 printk("CPU[%d]: Returns from cpu_idle!\n", smp_processor_id()); 119 panic("SMP bolixed\n"); 120 } 121 122 struct linux_prom_registers smp_penguin_ctable = { 0 }; 123 124 void smp_send_reschedule(int cpu) 125 { 126 /* 127 * CPU model dependent way of implementing IPI generation targeting 128 * a single CPU. The trap handler needs only to do trap entry/return 129 * to call schedule. 130 */ 131 sparc32_ipi_ops->resched(cpu); 132 } 133 134 void smp_send_stop(void) 135 { 136 } 137 138 void arch_send_call_function_single_ipi(int cpu) 139 { 140 /* trigger one IPI single call on one CPU */ 141 sparc32_ipi_ops->single(cpu); 142 } 143 144 void arch_send_call_function_ipi_mask(const struct cpumask *mask) 145 { 146 int cpu; 147 148 /* trigger IPI mask call on each CPU */ 149 for_each_cpu(cpu, mask) 150 sparc32_ipi_ops->mask_one(cpu); 151 } 152 153 void smp_resched_interrupt(void) 154 { 155 irq_enter(); 156 scheduler_ipi(); 157 local_cpu_data().irq_resched_count++; 158 irq_exit(); 159 /* re-schedule routine called by interrupt return code. */ 160 } 161 162 void smp_call_function_single_interrupt(void) 163 { 164 irq_enter(); 165 generic_smp_call_function_single_interrupt(); 166 local_cpu_data().irq_call_count++; 167 irq_exit(); 168 } 169 170 void smp_call_function_interrupt(void) 171 { 172 irq_enter(); 173 generic_smp_call_function_interrupt(); 174 local_cpu_data().irq_call_count++; 175 irq_exit(); 176 } 177 178 int setup_profiling_timer(unsigned int multiplier) 179 { 180 return -EINVAL; 181 } 182 183 void __init smp_prepare_cpus(unsigned int max_cpus) 184 { 185 int i, cpuid, extra; 186 187 printk("Entering SMP Mode...\n"); 188 189 extra = 0; 190 for (i = 0; !cpu_find_by_instance(i, NULL, &cpuid); i++) { 191 if (cpuid >= NR_CPUS) 192 extra++; 193 } 194 /* i = number of cpus */ 195 if (extra && max_cpus > i - extra) 196 printk("Warning: NR_CPUS is too low to start all cpus\n"); 197 198 smp_store_cpu_info(boot_cpu_id); 199 200 switch(sparc_cpu_model) { 201 case sun4m: 202 smp4m_boot_cpus(); 203 break; 204 case sun4d: 205 smp4d_boot_cpus(); 206 break; 207 case sparc_leon: 208 leon_boot_cpus(); 209 break; 210 case sun4e: 211 printk("SUN4E\n"); 212 BUG(); 213 break; 214 case sun4u: 215 printk("SUN4U\n"); 216 BUG(); 217 break; 218 default: 219 printk("UNKNOWN!\n"); 220 BUG(); 221 break; 222 } 223 } 224 225 /* Set this up early so that things like the scheduler can init 226 * properly. We use the same cpu mask for both the present and 227 * possible cpu map. 228 */ 229 void __init smp_setup_cpu_possible_map(void) 230 { 231 int instance, mid; 232 233 instance = 0; 234 while (!cpu_find_by_instance(instance, NULL, &mid)) { 235 if (mid < NR_CPUS) { 236 set_cpu_possible(mid, true); 237 set_cpu_present(mid, true); 238 } 239 instance++; 240 } 241 } 242 243 void __init smp_prepare_boot_cpu(void) 244 { 245 int cpuid = hard_smp_processor_id(); 246 247 if (cpuid >= NR_CPUS) { 248 prom_printf("Serious problem, boot cpu id >= NR_CPUS\n"); 249 prom_halt(); 250 } 251 if (cpuid != 0) 252 printk("boot cpu id != 0, this could work but is untested\n"); 253 254 current_thread_info()->cpu = cpuid; 255 set_cpu_online(cpuid, true); 256 set_cpu_possible(cpuid, true); 257 } 258 259 int __cpu_up(unsigned int cpu, struct task_struct *tidle) 260 { 261 int ret=0; 262 263 switch(sparc_cpu_model) { 264 case sun4m: 265 ret = smp4m_boot_one_cpu(cpu, tidle); 266 break; 267 case sun4d: 268 ret = smp4d_boot_one_cpu(cpu, tidle); 269 break; 270 case sparc_leon: 271 ret = leon_boot_one_cpu(cpu, tidle); 272 break; 273 case sun4e: 274 printk("SUN4E\n"); 275 BUG(); 276 break; 277 case sun4u: 278 printk("SUN4U\n"); 279 BUG(); 280 break; 281 default: 282 printk("UNKNOWN!\n"); 283 BUG(); 284 break; 285 } 286 287 if (!ret) { 288 cpumask_set_cpu(cpu, &smp_commenced_mask); 289 while (!cpu_online(cpu)) 290 mb(); 291 } 292 return ret; 293 } 294 295 static void arch_cpu_pre_starting(void *arg) 296 { 297 local_ops->cache_all(); 298 local_ops->tlb_all(); 299 300 switch(sparc_cpu_model) { 301 case sun4m: 302 sun4m_cpu_pre_starting(arg); 303 break; 304 case sun4d: 305 sun4d_cpu_pre_starting(arg); 306 break; 307 case sparc_leon: 308 leon_cpu_pre_starting(arg); 309 break; 310 default: 311 BUG(); 312 } 313 } 314 315 static void arch_cpu_pre_online(void *arg) 316 { 317 unsigned int cpuid = hard_smp_processor_id(); 318 319 register_percpu_ce(cpuid); 320 321 calibrate_delay(); 322 smp_store_cpu_info(cpuid); 323 324 local_ops->cache_all(); 325 local_ops->tlb_all(); 326 327 switch(sparc_cpu_model) { 328 case sun4m: 329 sun4m_cpu_pre_online(arg); 330 break; 331 case sun4d: 332 sun4d_cpu_pre_online(arg); 333 break; 334 case sparc_leon: 335 leon_cpu_pre_online(arg); 336 break; 337 default: 338 BUG(); 339 } 340 } 341 342 static void sparc_start_secondary(void *arg) 343 { 344 unsigned int cpu; 345 346 /* 347 * SMP booting is extremely fragile in some architectures. So run 348 * the cpu initialization code first before anything else. 349 */ 350 arch_cpu_pre_starting(arg); 351 352 preempt_disable(); 353 cpu = smp_processor_id(); 354 355 notify_cpu_starting(cpu); 356 arch_cpu_pre_online(arg); 357 358 /* Set the CPU in the cpu_online_mask */ 359 set_cpu_online(cpu, true); 360 361 /* Enable local interrupts now */ 362 local_irq_enable(); 363 364 wmb(); 365 cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); 366 367 /* We should never reach here! */ 368 BUG(); 369 } 370 371 void smp_callin(void) 372 { 373 sparc_start_secondary(NULL); 374 } 375 376 void smp_bogo(struct seq_file *m) 377 { 378 int i; 379 380 for_each_online_cpu(i) { 381 seq_printf(m, 382 "Cpu%dBogo\t: %lu.%02lu\n", 383 i, 384 cpu_data(i).udelay_val/(500000/HZ), 385 (cpu_data(i).udelay_val/(5000/HZ))%100); 386 } 387 } 388 389 void smp_info(struct seq_file *m) 390 { 391 int i; 392 393 seq_printf(m, "State:\n"); 394 for_each_online_cpu(i) 395 seq_printf(m, "CPU%d\t\t: online\n", i); 396 } 397