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/pgtable.h> 34 #include <asm/oplib.h> 35 #include <asm/cacheflush.h> 36 #include <asm/tlbflush.h> 37 #include <asm/cpudata.h> 38 #include <asm/timer.h> 39 #include <asm/leon.h> 40 41 #include "kernel.h" 42 #include "irq.h" 43 44 volatile unsigned long cpu_callin_map[NR_CPUS] = {0,}; 45 46 cpumask_t smp_commenced_mask = CPU_MASK_NONE; 47 48 const struct sparc32_ipi_ops *sparc32_ipi_ops; 49 50 /* The only guaranteed locking primitive available on all Sparc 51 * processors is 'ldstub [%reg + immediate], %dest_reg' which atomically 52 * places the current byte at the effective address into dest_reg and 53 * places 0xff there afterwards. Pretty lame locking primitive 54 * compared to the Alpha and the Intel no? Most Sparcs have 'swap' 55 * instruction which is much better... 56 */ 57 58 void smp_store_cpu_info(int id) 59 { 60 int cpu_node; 61 int mid; 62 63 cpu_data(id).udelay_val = loops_per_jiffy; 64 65 cpu_find_by_mid(id, &cpu_node); 66 cpu_data(id).clock_tick = prom_getintdefault(cpu_node, 67 "clock-frequency", 0); 68 cpu_data(id).prom_node = cpu_node; 69 mid = cpu_get_hwmid(cpu_node); 70 71 if (mid < 0) { 72 printk(KERN_NOTICE "No MID found for CPU%d at node 0x%08x", id, cpu_node); 73 mid = 0; 74 } 75 cpu_data(id).mid = mid; 76 } 77 78 void __init smp_cpus_done(unsigned int max_cpus) 79 { 80 unsigned long bogosum = 0; 81 int cpu, num = 0; 82 83 for_each_online_cpu(cpu) { 84 num++; 85 bogosum += cpu_data(cpu).udelay_val; 86 } 87 88 printk("Total of %d processors activated (%lu.%02lu BogoMIPS).\n", 89 num, bogosum/(500000/HZ), 90 (bogosum/(5000/HZ))%100); 91 92 switch(sparc_cpu_model) { 93 case sun4m: 94 smp4m_smp_done(); 95 break; 96 case sun4d: 97 smp4d_smp_done(); 98 break; 99 case sparc_leon: 100 leon_smp_done(); 101 break; 102 case sun4e: 103 printk("SUN4E\n"); 104 BUG(); 105 break; 106 case sun4u: 107 printk("SUN4U\n"); 108 BUG(); 109 break; 110 default: 111 printk("UNKNOWN!\n"); 112 BUG(); 113 break; 114 } 115 } 116 117 void cpu_panic(void) 118 { 119 printk("CPU[%d]: Returns from cpu_idle!\n", smp_processor_id()); 120 panic("SMP bolixed\n"); 121 } 122 123 struct linux_prom_registers smp_penguin_ctable = { 0 }; 124 125 void smp_send_reschedule(int cpu) 126 { 127 /* 128 * CPU model dependent way of implementing IPI generation targeting 129 * a single CPU. The trap handler needs only to do trap entry/return 130 * to call schedule. 131 */ 132 sparc32_ipi_ops->resched(cpu); 133 } 134 135 void smp_send_stop(void) 136 { 137 } 138 139 void arch_send_call_function_single_ipi(int cpu) 140 { 141 /* trigger one IPI single call on one CPU */ 142 sparc32_ipi_ops->single(cpu); 143 } 144 145 void arch_send_call_function_ipi_mask(const struct cpumask *mask) 146 { 147 int cpu; 148 149 /* trigger IPI mask call on each CPU */ 150 for_each_cpu(cpu, mask) 151 sparc32_ipi_ops->mask_one(cpu); 152 } 153 154 void smp_resched_interrupt(void) 155 { 156 irq_enter(); 157 scheduler_ipi(); 158 local_cpu_data().irq_resched_count++; 159 irq_exit(); 160 /* re-schedule routine called by interrupt return code. */ 161 } 162 163 void smp_call_function_single_interrupt(void) 164 { 165 irq_enter(); 166 generic_smp_call_function_single_interrupt(); 167 local_cpu_data().irq_call_count++; 168 irq_exit(); 169 } 170 171 void smp_call_function_interrupt(void) 172 { 173 irq_enter(); 174 generic_smp_call_function_interrupt(); 175 local_cpu_data().irq_call_count++; 176 irq_exit(); 177 } 178 179 int setup_profiling_timer(unsigned int multiplier) 180 { 181 return -EINVAL; 182 } 183 184 void __init smp_prepare_cpus(unsigned int max_cpus) 185 { 186 int i, cpuid, extra; 187 188 printk("Entering SMP Mode...\n"); 189 190 extra = 0; 191 for (i = 0; !cpu_find_by_instance(i, NULL, &cpuid); i++) { 192 if (cpuid >= NR_CPUS) 193 extra++; 194 } 195 /* i = number of cpus */ 196 if (extra && max_cpus > i - extra) 197 printk("Warning: NR_CPUS is too low to start all cpus\n"); 198 199 smp_store_cpu_info(boot_cpu_id); 200 201 switch(sparc_cpu_model) { 202 case sun4m: 203 smp4m_boot_cpus(); 204 break; 205 case sun4d: 206 smp4d_boot_cpus(); 207 break; 208 case sparc_leon: 209 leon_boot_cpus(); 210 break; 211 case sun4e: 212 printk("SUN4E\n"); 213 BUG(); 214 break; 215 case sun4u: 216 printk("SUN4U\n"); 217 BUG(); 218 break; 219 default: 220 printk("UNKNOWN!\n"); 221 BUG(); 222 break; 223 } 224 } 225 226 /* Set this up early so that things like the scheduler can init 227 * properly. We use the same cpu mask for both the present and 228 * possible cpu map. 229 */ 230 void __init smp_setup_cpu_possible_map(void) 231 { 232 int instance, mid; 233 234 instance = 0; 235 while (!cpu_find_by_instance(instance, NULL, &mid)) { 236 if (mid < NR_CPUS) { 237 set_cpu_possible(mid, true); 238 set_cpu_present(mid, true); 239 } 240 instance++; 241 } 242 } 243 244 void __init smp_prepare_boot_cpu(void) 245 { 246 int cpuid = hard_smp_processor_id(); 247 248 if (cpuid >= NR_CPUS) { 249 prom_printf("Serious problem, boot cpu id >= NR_CPUS\n"); 250 prom_halt(); 251 } 252 if (cpuid != 0) 253 printk("boot cpu id != 0, this could work but is untested\n"); 254 255 current_thread_info()->cpu = cpuid; 256 set_cpu_online(cpuid, true); 257 set_cpu_possible(cpuid, true); 258 } 259 260 int __cpu_up(unsigned int cpu, struct task_struct *tidle) 261 { 262 int ret=0; 263 264 switch(sparc_cpu_model) { 265 case sun4m: 266 ret = smp4m_boot_one_cpu(cpu, tidle); 267 break; 268 case sun4d: 269 ret = smp4d_boot_one_cpu(cpu, tidle); 270 break; 271 case sparc_leon: 272 ret = leon_boot_one_cpu(cpu, tidle); 273 break; 274 case sun4e: 275 printk("SUN4E\n"); 276 BUG(); 277 break; 278 case sun4u: 279 printk("SUN4U\n"); 280 BUG(); 281 break; 282 default: 283 printk("UNKNOWN!\n"); 284 BUG(); 285 break; 286 } 287 288 if (!ret) { 289 cpumask_set_cpu(cpu, &smp_commenced_mask); 290 while (!cpu_online(cpu)) 291 mb(); 292 } 293 return ret; 294 } 295 296 static void arch_cpu_pre_starting(void *arg) 297 { 298 local_ops->cache_all(); 299 local_ops->tlb_all(); 300 301 switch(sparc_cpu_model) { 302 case sun4m: 303 sun4m_cpu_pre_starting(arg); 304 break; 305 case sun4d: 306 sun4d_cpu_pre_starting(arg); 307 break; 308 case sparc_leon: 309 leon_cpu_pre_starting(arg); 310 break; 311 default: 312 BUG(); 313 } 314 } 315 316 static void arch_cpu_pre_online(void *arg) 317 { 318 unsigned int cpuid = hard_smp_processor_id(); 319 320 register_percpu_ce(cpuid); 321 322 calibrate_delay(); 323 smp_store_cpu_info(cpuid); 324 325 local_ops->cache_all(); 326 local_ops->tlb_all(); 327 328 switch(sparc_cpu_model) { 329 case sun4m: 330 sun4m_cpu_pre_online(arg); 331 break; 332 case sun4d: 333 sun4d_cpu_pre_online(arg); 334 break; 335 case sparc_leon: 336 leon_cpu_pre_online(arg); 337 break; 338 default: 339 BUG(); 340 } 341 } 342 343 static void sparc_start_secondary(void *arg) 344 { 345 unsigned int cpu; 346 347 /* 348 * SMP booting is extremely fragile in some architectures. So run 349 * the cpu initialization code first before anything else. 350 */ 351 arch_cpu_pre_starting(arg); 352 353 preempt_disable(); 354 cpu = smp_processor_id(); 355 356 notify_cpu_starting(cpu); 357 arch_cpu_pre_online(arg); 358 359 /* Set the CPU in the cpu_online_mask */ 360 set_cpu_online(cpu, true); 361 362 /* Enable local interrupts now */ 363 local_irq_enable(); 364 365 wmb(); 366 cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); 367 368 /* We should never reach here! */ 369 BUG(); 370 } 371 372 void smp_callin(void) 373 { 374 sparc_start_secondary(NULL); 375 } 376 377 void smp_bogo(struct seq_file *m) 378 { 379 int i; 380 381 for_each_online_cpu(i) { 382 seq_printf(m, 383 "Cpu%dBogo\t: %lu.%02lu\n", 384 i, 385 cpu_data(i).udelay_val/(500000/HZ), 386 (cpu_data(i).udelay_val/(5000/HZ))%100); 387 } 388 } 389 390 void smp_info(struct seq_file *m) 391 { 392 int i; 393 394 seq_printf(m, "State:\n"); 395 for_each_online_cpu(i) 396 seq_printf(m, "CPU%d\t\t: online\n", i); 397 } 398