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