1 files changed, 85 insertions, 0 deletions
diff --git a/arch/mips/include/asm/switch_to.h b/arch/mips/include/asm/switch_to.h
new file mode 100644
index 00000000000..5d33621b565
--- /dev/null
+++ b/arch/mips/include/asm/switch_to.h
@@ -0,0 +1,85 @@
+/*
+ * 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) 1994, 95, 96, 97, 98, 99, 2003, 06 by Ralf Baechle
+ * Copyright (C) 1996 by Paul M. Antoine
+ * Copyright (C) 1999 Silicon Graphics
+ * Kevin D. Kissell, kevink@mips.org and Carsten Langgaard, carstenl@mips.com
+ * Copyright (C) 2000 MIPS Technologies, Inc.
+ */
+#ifndef _ASM_SWITCH_TO_H
+#define _ASM_SWITCH_TO_H
+
+#include <asm/cpu-features.h>
+#include <asm/watch.h>
+#include <asm/dsp.h>
+
+struct task_struct;
+
+/*
+ * switch_to(n) should switch tasks to task nr n, first
+ * checking that n isn't the current task, in which case it does nothing.
+ */
+extern asmlinkage void *resume(void *last, void *next, void *next_ti);
+
+extern unsigned int ll_bit;
+extern struct task_struct *ll_task;
+
+#ifdef CONFIG_MIPS_MT_FPAFF
+
+/*
+ * Handle the scheduler resume end of FPU affinity management.  We do this
+ * inline to try to keep the overhead down. If we have been forced to run on
+ * a "CPU" with an FPU because of a previous high level of FP computation,
+ * but did not actually use the FPU during the most recent time-slice (CU1
+ * isn't set), we undo the restriction on cpus_allowed.
+ *
+ * We're not calling set_cpus_allowed() here, because we have no need to
+ * force prompt migration - we're already switching the current CPU to a
+ * different thread.
+ */
+
+#define __mips_mt_fpaff_switch_to(prev)					\
+do {									\
+	struct thread_info *__prev_ti = task_thread_info(prev);		\
+									\
+	if (cpu_has_fpu &&						\
+	    test_ti_thread_flag(__prev_ti, TIF_FPUBOUND) &&		\
+	    (!(KSTK_STATUS(prev) & ST0_CU1))) {				\
+		clear_ti_thread_flag(__prev_ti, TIF_FPUBOUND);		\
+		prev->cpus_allowed = prev->thread.user_cpus_allowed;	\
+	}								\
+	next->thread.emulated_fp = 0;					\
+} while(0)
+
+#else
+#define __mips_mt_fpaff_switch_to(prev) do { (void) (prev); } while (0)
+#endif
+
+#define __clear_software_ll_bit()					\
+do {									\
+	if (!__builtin_constant_p(cpu_has_llsc) || !cpu_has_llsc)	\
+		ll_bit = 0;						\
+} while (0)
+
+#define switch_to(prev, next, last)					\
+do {									\
+	__mips_mt_fpaff_switch_to(prev);				\
+	if (cpu_has_dsp)						\
+		__save_dsp(prev);					\
+	__clear_software_ll_bit();					\
+	(last) = resume(prev, next, task_thread_info(next));		\
+} while (0)
+
+#define finish_arch_switch(prev)					\
+do {									\
+	if (cpu_has_dsp)						\
+		__restore_dsp(current);					\
+	if (cpu_has_userlocal)						\
+		write_c0_userlocal(current_thread_info()->tp_value);	\
+	__restore_watch();						\
+} while (0)
+
+#endif /* _ASM_SWITCH_TO_H */