arch/sh/kernel/smp.c

   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 }