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38#include <linux/module.h>
39#include <linux/kernel.h>
40#include <linux/init.h>
41#include <linux/interrupt.h>
42#include <linux/seq_file.h>
43
44#include <asm/cacheflush.h>
45#include <asm/cp15.h>
46#include <asm/fiq.h>
47#include <asm/irq.h>
48#include <asm/traps.h>
49
50#define FIQ_OFFSET ({ \
51 extern void *vector_fiq_offset; \
52 (unsigned)&vector_fiq_offset; \
53 })
54
55static unsigned long dfl_fiq_insn;
56static struct pt_regs dfl_fiq_regs;
57
58
59
60
61
62static int fiq_def_op(void *ref, int relinquish)
63{
64 if (!relinquish) {
65
66 local_fiq_disable();
67 set_fiq_regs(&dfl_fiq_regs);
68 set_fiq_handler(&dfl_fiq_insn, sizeof(dfl_fiq_insn));
69 local_fiq_enable();
70
71
72 }
73
74 return 0;
75}
76
77static struct fiq_handler default_owner = {
78 .name = "default",
79 .fiq_op = fiq_def_op,
80};
81
82static struct fiq_handler *current_fiq = &default_owner;
83
84int show_fiq_list(struct seq_file *p, int prec)
85{
86 if (current_fiq != &default_owner)
87 seq_printf(p, "%*s: %s\n", prec, "FIQ",
88 current_fiq->name);
89
90 return 0;
91}
92
93void set_fiq_handler(void *start, unsigned int length)
94{
95 void *base = vectors_page;
96 unsigned offset = FIQ_OFFSET;
97
98 memcpy(base + offset, start, length);
99 if (!cache_is_vipt_nonaliasing())
100 flush_icache_range((unsigned long)base + offset, offset +
101 length);
102 flush_icache_range(0xffff0000 + offset, 0xffff0000 + offset + length);
103}
104
105int claim_fiq(struct fiq_handler *f)
106{
107 int ret = 0;
108
109 if (current_fiq) {
110 ret = -EBUSY;
111
112 if (current_fiq->fiq_op != NULL)
113 ret = current_fiq->fiq_op(current_fiq->dev_id, 1);
114 }
115
116 if (!ret) {
117 f->next = current_fiq;
118 current_fiq = f;
119 }
120
121 return ret;
122}
123
124void release_fiq(struct fiq_handler *f)
125{
126 if (current_fiq != f) {
127 pr_err("%s FIQ trying to release %s FIQ\n",
128 f->name, current_fiq->name);
129 dump_stack();
130 return;
131 }
132
133 do
134 current_fiq = current_fiq->next;
135 while (current_fiq->fiq_op(current_fiq->dev_id, 0));
136}
137
138static int fiq_start;
139
140void enable_fiq(int fiq)
141{
142 enable_irq(fiq + fiq_start);
143}
144
145void disable_fiq(int fiq)
146{
147 disable_irq(fiq + fiq_start);
148}
149
150EXPORT_SYMBOL(set_fiq_handler);
151EXPORT_SYMBOL(__set_fiq_regs);
152EXPORT_SYMBOL(__get_fiq_regs);
153EXPORT_SYMBOL(claim_fiq);
154EXPORT_SYMBOL(release_fiq);
155EXPORT_SYMBOL(enable_fiq);
156EXPORT_SYMBOL(disable_fiq);
157
158void __init init_FIQ(int start)
159{
160 unsigned offset = FIQ_OFFSET;
161 dfl_fiq_insn = *(unsigned long *)(0xffff0000 + offset);
162 get_fiq_regs(&dfl_fiq_regs);
163 fiq_start = start;
164}
165