arch/mn10300/mm/cache-smp.c

   1 /* SMP global caching code
   2  *
   3  * Copyright (C) 2010 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public Licence
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the Licence, or (at your option) any later version.
  10  */
  11 #include <linux/module.h>
  12 #include <linux/mm.h>
  13 #include <linux/mman.h>
  14 #include <linux/threads.h>
  15 #include <linux/interrupt.h>
  16 #include <asm/page.h>
  17 #include <asm/pgtable.h>
  18 #include <asm/processor.h>
  19 #include <asm/cacheflush.h>
  20 #include <asm/io.h>
  21 #include <asm/uaccess.h>
  22 #include <asm/smp.h>
  23 #include "cache-smp.h"
  24
  25 DEFINE_SPINLOCK(smp_cache_lock);
  26 static unsigned long smp_cache_mask;
  27 static unsigned long smp_cache_start;
  28 static unsigned long smp_cache_end;
  29 static cpumask_t smp_cache_ipi_map;             /* Bitmask of cache IPI done CPUs */
  30
  31 /**
  32  * smp_cache_interrupt - Handle IPI request to flush caches.
  33  *
  34  * Handle a request delivered by IPI to flush the current CPU's
  35  * caches.  The parameters are stored in smp_cache_*.
  36  */
  37 void smp_cache_interrupt(void)
  38 {
  39         unsigned long opr_mask = smp_cache_mask;
  40
  41         switch ((enum smp_dcache_ops)(opr_mask & SMP_DCACHE_OP_MASK)) {
  42         case SMP_DCACHE_NOP:
  43                 break;
  44         case SMP_DCACHE_INV:
  45                 mn10300_local_dcache_inv();
  46                 break;
  47         case SMP_DCACHE_INV_RANGE:
  48                 mn10300_local_dcache_inv_range(smp_cache_start, smp_cache_end);
  49                 break;
  50         case SMP_DCACHE_FLUSH:
  51                 mn10300_local_dcache_flush();
  52                 break;
  53         case SMP_DCACHE_FLUSH_RANGE:
  54                 mn10300_local_dcache_flush_range(smp_cache_start,
  55                                                  smp_cache_end);
  56                 break;
  57         case SMP_DCACHE_FLUSH_INV:
  58                 mn10300_local_dcache_flush_inv();
  59                 break;
  60         case SMP_DCACHE_FLUSH_INV_RANGE:
  61                 mn10300_local_dcache_flush_inv_range(smp_cache_start,
  62                                                      smp_cache_end);
  63                 break;
  64         }
  65
  66         switch ((enum smp_icache_ops)(opr_mask & SMP_ICACHE_OP_MASK)) {
  67         case SMP_ICACHE_NOP:
  68                 break;
  69         case SMP_ICACHE_INV:
  70                 mn10300_local_icache_inv();
  71                 break;
  72         case SMP_ICACHE_INV_RANGE:
  73                 mn10300_local_icache_inv_range(smp_cache_start, smp_cache_end);
  74                 break;
  75         }
  76
  77         cpumask_clear_cpu(smp_processor_id(), &smp_cache_ipi_map);
  78 }
  79
  80 /**
  81  * smp_cache_call - Issue an IPI to request the other CPUs flush caches
  82  * @opr_mask: Cache operation flags
  83  * @start: Start address of request
  84  * @end: End address of request
  85  *
  86  * Send cache flush IPI to other CPUs.  This invokes smp_cache_interrupt()
  87  * above on those other CPUs and then waits for them to finish.
  88  *
  89  * The caller must hold smp_cache_lock.
  90  */
  91 void smp_cache_call(unsigned long opr_mask,
  92                     unsigned long start, unsigned long end)
  93 {
  94         smp_cache_mask = opr_mask;
  95         smp_cache_start = start;
  96         smp_cache_end = end;
  97         cpumask_copy(&smp_cache_ipi_map, cpu_online_mask);
  98         cpumask_clear_cpu(smp_processor_id(), &smp_cache_ipi_map);
  99
 100         send_IPI_allbutself(FLUSH_CACHE_IPI);
 101
 102         while (!cpumask_empty(&smp_cache_ipi_map))
 103                 /* nothing. lockup detection does not belong here */
 104                 mb();
 105 }