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 */
smp_cache_interrupt(void)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 */
smp_cache_call(unsigned long opr_mask,unsigned long start,unsigned long end)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 }
106