1 /* 2 * arch/sh/kernel/smp.c 3 * 4 * SMP support for the SuperH processors. 5 * 6 * Copyright (C) 2002 - 2008 Paul Mundt 7 * Copyright (C) 2006 - 2007 Akio Idehara 8 * 9 * This file is subject to the terms and conditions of the GNU General Public 10 * License. See the file "COPYING" in the main directory of this archive 11 * for more details. 12 */ 13 #include <linux/err.h> 14 #include <linux/cache.h> 15 #include <linux/cpumask.h> 16 #include <linux/delay.h> 17 #include <linux/init.h> 18 #include <linux/spinlock.h> 19 #include <linux/mm.h> 20 #include <linux/module.h> 21 #include <linux/cpu.h> 22 #include <linux/interrupt.h> 23 #include <asm/atomic.h> 24 #include <asm/processor.h> 25 #include <asm/system.h> 26 #include <asm/mmu_context.h> 27 #include <asm/smp.h> 28 #include <asm/cacheflush.h> 29 #include <asm/sections.h> 30 31 int __cpu_number_map[NR_CPUS]; /* Map physical to logical */ 32 int __cpu_logical_map[NR_CPUS]; /* Map logical to physical */ 33 34 static inline void __init smp_store_cpu_info(unsigned int cpu) 35 { 36 struct sh_cpuinfo *c = cpu_data + cpu; 37 38 memcpy(c, &boot_cpu_data, sizeof(struct sh_cpuinfo)); 39 40 c->loops_per_jiffy = loops_per_jiffy; 41 } 42 43 void __init smp_prepare_cpus(unsigned int max_cpus) 44 { 45 unsigned int cpu = smp_processor_id(); 46 47 init_new_context(current, &init_mm); 48 current_thread_info()->cpu = cpu; 49 plat_prepare_cpus(max_cpus); 50 51 #ifndef CONFIG_HOTPLUG_CPU 52 init_cpu_present(&cpu_possible_map); 53 #endif 54 } 55 56 void __devinit smp_prepare_boot_cpu(void) 57 { 58 unsigned int cpu = smp_processor_id(); 59 60 __cpu_number_map[0] = cpu; 61 __cpu_logical_map[0] = cpu; 62 63 set_cpu_online(cpu, true); 64 set_cpu_possible(cpu, true); 65 } 66 67 asmlinkage void __cpuinit start_secondary(void) 68 { 69 unsigned int cpu; 70 struct mm_struct *mm = &init_mm; 71 72 enable_mmu(); 73 atomic_inc(&mm->mm_count); 74 atomic_inc(&mm->mm_users); 75 current->active_mm = mm; 76 BUG_ON(current->mm); 77 enter_lazy_tlb(mm, current); 78 79 per_cpu_trap_init(); 80 81 preempt_disable(); 82 83 notify_cpu_starting(smp_processor_id()); 84 85 local_irq_enable(); 86 87 cpu = smp_processor_id(); 88 89 /* Enable local timers */ 90 local_timer_setup(cpu); 91 calibrate_delay(); 92 93 smp_store_cpu_info(cpu); 94 95 cpu_set(cpu, cpu_online_map); 96 97 cpu_idle(); 98 } 99 100 extern struct { 101 unsigned long sp; 102 unsigned long bss_start; 103 unsigned long bss_end; 104 void *start_kernel_fn; 105 void *cpu_init_fn; 106 void *thread_info; 107 } stack_start; 108 109 int __cpuinit __cpu_up(unsigned int cpu) 110 { 111 struct task_struct *tsk; 112 unsigned long timeout; 113 114 tsk = fork_idle(cpu); 115 if (IS_ERR(tsk)) { 116 printk(KERN_ERR "Failed forking idle task for cpu %d\n", cpu); 117 return PTR_ERR(tsk); 118 } 119 120 /* Fill in data in head.S for secondary cpus */ 121 stack_start.sp = tsk->thread.sp; 122 stack_start.thread_info = tsk->stack; 123 stack_start.bss_start = 0; /* don't clear bss for secondary cpus */ 124 stack_start.start_kernel_fn = start_secondary; 125 126 flush_icache_range((unsigned long)&stack_start, 127 (unsigned long)&stack_start + sizeof(stack_start)); 128 wmb(); 129 130 plat_start_cpu(cpu, (unsigned long)_stext); 131 132 timeout = jiffies + HZ; 133 while (time_before(jiffies, timeout)) { 134 if (cpu_online(cpu)) 135 break; 136 137 udelay(10); 138 } 139 140 if (cpu_online(cpu)) 141 return 0; 142 143 return -ENOENT; 144 } 145 146 void __init smp_cpus_done(unsigned int max_cpus) 147 { 148 unsigned long bogosum = 0; 149 int cpu; 150 151 for_each_online_cpu(cpu) 152 bogosum += cpu_data[cpu].loops_per_jiffy; 153 154 printk(KERN_INFO "SMP: Total of %d processors activated " 155 "(%lu.%02lu BogoMIPS).\n", num_online_cpus(), 156 bogosum / (500000/HZ), 157 (bogosum / (5000/HZ)) % 100); 158 } 159 160 void smp_send_reschedule(int cpu) 161 { 162 plat_send_ipi(cpu, SMP_MSG_RESCHEDULE); 163 } 164 165 void smp_send_stop(void) 166 { 167 smp_call_function(stop_this_cpu, 0, 0); 168 } 169 170 void arch_send_call_function_ipi_mask(const struct cpumask *mask) 171 { 172 int cpu; 173 174 for_each_cpu(cpu, mask) 175 plat_send_ipi(cpu, SMP_MSG_FUNCTION); 176 } 177 178 void arch_send_call_function_single_ipi(int cpu) 179 { 180 plat_send_ipi(cpu, SMP_MSG_FUNCTION_SINGLE); 181 } 182 183 void smp_timer_broadcast(const struct cpumask *mask) 184 { 185 int cpu; 186 187 for_each_cpu(cpu, mask) 188 plat_send_ipi(cpu, SMP_MSG_TIMER); 189 } 190 191 static void ipi_timer(void) 192 { 193 irq_enter(); 194 local_timer_interrupt(); 195 irq_exit(); 196 } 197 198 void smp_message_recv(unsigned int msg) 199 { 200 switch (msg) { 201 case SMP_MSG_FUNCTION: 202 generic_smp_call_function_interrupt(); 203 break; 204 case SMP_MSG_RESCHEDULE: 205 break; 206 case SMP_MSG_FUNCTION_SINGLE: 207 generic_smp_call_function_single_interrupt(); 208 break; 209 case SMP_MSG_TIMER: 210 ipi_timer(); 211 break; 212 default: 213 printk(KERN_WARNING "SMP %d: %s(): unknown IPI %d\n", 214 smp_processor_id(), __func__, msg); 215 break; 216 } 217 } 218 219 /* Not really SMP stuff ... */ 220 int setup_profiling_timer(unsigned int multiplier) 221 { 222 return 0; 223 } 224 225 static void flush_tlb_all_ipi(void *info) 226 { 227 local_flush_tlb_all(); 228 } 229 230 void flush_tlb_all(void) 231 { 232 on_each_cpu(flush_tlb_all_ipi, 0, 1); 233 } 234 235 static void flush_tlb_mm_ipi(void *mm) 236 { 237 local_flush_tlb_mm((struct mm_struct *)mm); 238 } 239 240 /* 241 * The following tlb flush calls are invoked when old translations are 242 * being torn down, or pte attributes are changing. For single threaded 243 * address spaces, a new context is obtained on the current cpu, and tlb 244 * context on other cpus are invalidated to force a new context allocation 245 * at switch_mm time, should the mm ever be used on other cpus. For 246 * multithreaded address spaces, intercpu interrupts have to be sent. 247 * Another case where intercpu interrupts are required is when the target 248 * mm might be active on another cpu (eg debuggers doing the flushes on 249 * behalf of debugees, kswapd stealing pages from another process etc). 250 * Kanoj 07/00. 251 */ 252 253 void flush_tlb_mm(struct mm_struct *mm) 254 { 255 preempt_disable(); 256 257 if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) { 258 smp_call_function(flush_tlb_mm_ipi, (void *)mm, 1); 259 } else { 260 int i; 261 for (i = 0; i < num_online_cpus(); i++) 262 if (smp_processor_id() != i) 263 cpu_context(i, mm) = 0; 264 } 265 local_flush_tlb_mm(mm); 266 267 preempt_enable(); 268 } 269 270 struct flush_tlb_data { 271 struct vm_area_struct *vma; 272 unsigned long addr1; 273 unsigned long addr2; 274 }; 275 276 static void flush_tlb_range_ipi(void *info) 277 { 278 struct flush_tlb_data *fd = (struct flush_tlb_data *)info; 279 280 local_flush_tlb_range(fd->vma, fd->addr1, fd->addr2); 281 } 282 283 void flush_tlb_range(struct vm_area_struct *vma, 284 unsigned long start, unsigned long end) 285 { 286 struct mm_struct *mm = vma->vm_mm; 287 288 preempt_disable(); 289 if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) { 290 struct flush_tlb_data fd; 291 292 fd.vma = vma; 293 fd.addr1 = start; 294 fd.addr2 = end; 295 smp_call_function(flush_tlb_range_ipi, (void *)&fd, 1); 296 } else { 297 int i; 298 for (i = 0; i < num_online_cpus(); i++) 299 if (smp_processor_id() != i) 300 cpu_context(i, mm) = 0; 301 } 302 local_flush_tlb_range(vma, start, end); 303 preempt_enable(); 304 } 305 306 static void flush_tlb_kernel_range_ipi(void *info) 307 { 308 struct flush_tlb_data *fd = (struct flush_tlb_data *)info; 309 310 local_flush_tlb_kernel_range(fd->addr1, fd->addr2); 311 } 312 313 void flush_tlb_kernel_range(unsigned long start, unsigned long end) 314 { 315 struct flush_tlb_data fd; 316 317 fd.addr1 = start; 318 fd.addr2 = end; 319 on_each_cpu(flush_tlb_kernel_range_ipi, (void *)&fd, 1); 320 } 321 322 static void flush_tlb_page_ipi(void *info) 323 { 324 struct flush_tlb_data *fd = (struct flush_tlb_data *)info; 325 326 local_flush_tlb_page(fd->vma, fd->addr1); 327 } 328 329 void flush_tlb_page(struct vm_area_struct *vma, unsigned long page) 330 { 331 preempt_disable(); 332 if ((atomic_read(&vma->vm_mm->mm_users) != 1) || 333 (current->mm != vma->vm_mm)) { 334 struct flush_tlb_data fd; 335 336 fd.vma = vma; 337 fd.addr1 = page; 338 smp_call_function(flush_tlb_page_ipi, (void *)&fd, 1); 339 } else { 340 int i; 341 for (i = 0; i < num_online_cpus(); i++) 342 if (smp_processor_id() != i) 343 cpu_context(i, vma->vm_mm) = 0; 344 } 345 local_flush_tlb_page(vma, page); 346 preempt_enable(); 347 } 348 349 static void flush_tlb_one_ipi(void *info) 350 { 351 struct flush_tlb_data *fd = (struct flush_tlb_data *)info; 352 local_flush_tlb_one(fd->addr1, fd->addr2); 353 } 354 355 void flush_tlb_one(unsigned long asid, unsigned long vaddr) 356 { 357 struct flush_tlb_data fd; 358 359 fd.addr1 = asid; 360 fd.addr2 = vaddr; 361 362 smp_call_function(flush_tlb_one_ipi, (void *)&fd, 1); 363 local_flush_tlb_one(asid, vaddr); 364 } 365