summaryrefslogtreecommitdiff
path: root/arch/mips/loongson64/cop2-ex.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/mips/loongson64/cop2-ex.c')
-rw-r--r--arch/mips/loongson64/cop2-ex.c61
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);