cache-smp.c revision 8be062892365b09f41d64cda7fa63d306e95e0c9 
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
25DEFINE_SPINLOCK(smp_cache_lock);
26static unsigned long smp_cache_mask;
27static unsigned long smp_cache_start;
28static unsigned long smp_cache_end;
29static 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 */
37void 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	cpu_clear(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 */
91void 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	smp_cache_ipi_map = cpu_online_map;
98	cpu_clear(smp_processor_id(), smp_cache_ipi_map);
99
100	send_IPI_allbutself(FLUSH_CACHE_IPI);
101
102	while (!cpus_empty(smp_cache_ipi_map))
103		/* nothing. lockup detection does not belong here */
104		mb();
105}
106