1 files changed, 63 insertions, 0 deletions

diff --git a/arch/mips/loongson/loongson-3/cop2-ex.c b/arch/mips/loongson/loongson-3/cop2-ex.c
new file mode 100644
index 000000000000..9182e8d2967c
--- /dev/null
+++ b/arch/mips/loongson/loongson-3/cop2-ex.c
@@ -0,0 +1,63 @@
+/*
+ * 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);