diff options
Diffstat (limited to 'arch/mips/loongson64/cop2-ex.c')
| -rw-r--r-- | arch/mips/loongson64/cop2-ex.c | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/arch/mips/loongson64/cop2-ex.c b/arch/mips/loongson64/cop2-ex.c new file mode 100644 index 000000000000..9efdfe430ff0 --- /dev/null +++ b/arch/mips/loongson64/cop2-ex.c @@ -0,0 +1,61 @@ +/* + * 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 <linux/ptrace.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_owned; + int fr = !test_thread_flag(TIF_32BIT_FPREGS); + + switch (action) { + case CU2_EXCEPTION: + preempt_disable(); + fpu_owned = __is_fpu_owner(); + 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 owned, we needn't init or restore fp */ + if (!fpu_owned) { + set_thread_flag(TIF_USEDFPU); + init_fp_ctx(current); + _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); |