mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-29 14:05:19 +08:00
64 lines
1.6 KiB
C
64 lines
1.6 KiB
C
|
/*
|
||
|
|
* 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);
|