/* * 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); if (!used_math()) { _init_fpu(current->thread.fpu.fcr31); 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);