blob: 9182e8d2967c774ff39456968d07d832773fe362 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
|
/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2014 Lemote Corporation.
* written by Huacai Chen <chenhc@lemote.com>
*
* based on arch/mips/cavium-octeon/cpu.c
* Copyright (C) 2009 Wind River Systems,
* written by Ralf Baechle <ralf@linux-mips.org>
*/
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/notifier.h>
#include <asm/fpu.h>
#include <asm/cop2.h>
#include <asm/current.h>
#include <asm/mipsregs.h>
static int loongson_cu2_call(struct notifier_block *nfb, unsigned long action,
void *data)
{
int fpu_enabled;
int fr = !test_thread_flag(TIF_32BIT_FPREGS);
switch (action) {
case CU2_EXCEPTION:
preempt_disable();
fpu_enabled = read_c0_status() & ST0_CU1;
if (!fr)
set_c0_status(ST0_CU1 | ST0_CU2);
else
set_c0_status(ST0_CU1 | ST0_CU2 | ST0_FR);
enable_fpu_hazard();
KSTK_STATUS(current) |= (ST0_CU1 | ST0_CU2);
if (fr)
KSTK_STATUS(current) |= ST0_FR;
else
KSTK_STATUS(current) &= ~ST0_FR;
/* If FPU is enabled, we needn't init or restore fp */
if(!fpu_enabled) {
set_thread_flag(TIF_USEDFPU);
if (!used_math()) {
_init_fpu();
set_used_math();
} else
_restore_fp(current);
}
preempt_enable();
return NOTIFY_STOP; /* Don't call default notifier */
}
return NOTIFY_OK; /* Let default notifier send signals */
}
static int __init loongson_cu2_setup(void)
{
return cu2_notifier(loongson_cu2_call, 0);
}
early_initcall(loongson_cu2_setup);
|
