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diff --git a/arch/xtensa/kernel/coprocessor.S b/arch/xtensa/kernel/coprocessor.S
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+/*
+ * arch/xtensa/kernel/coprocessor.S
+ *
+ * Xtensa processor configuration-specific table of coprocessor and
+ * other custom register layout information.
+ *
+ * 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) 2003 - 2007 Tensilica Inc.
+ */
+
+
+#include <linux/linkage.h>
+#include <asm/asm-offsets.h>
+#include <asm/processor.h>
+#include <asm/coprocessor.h>
+#include <asm/thread_info.h>
+#include <asm/uaccess.h>
+#include <asm/unistd.h>
+#include <asm/ptrace.h>
+#include <asm/current.h>
+#include <asm/pgtable.h>
+#include <asm/page.h>
+#include <asm/signal.h>
+#include <asm/tlbflush.h>
+
+/*
+ * Entry condition:
+ *
+ *   a0:	trashed, original value saved on stack (PT_AREG0)
+ *   a1:	a1
+ *   a2:	new stack pointer, original in DEPC
+ *   a3:	a3
+ *   depc:	a2, original value saved on stack (PT_DEPC)
+ *   excsave_1:	dispatch table
+ *
+ *   PT_DEPC >= VALID_DOUBLE_EXCEPTION_ADDRESS: double exception, DEPC
+ *	     <  VALID_DOUBLE_EXCEPTION_ADDRESS: regular exception
+ */
+
+/* IO protection is currently unsupported. */
+
+ENTRY(fast_io_protect)
+
+	wsr	a0, excsave1
+	movi	a0, unrecoverable_exception
+	callx0	a0
+
+ENDPROC(fast_io_protect)
+
+#if XTENSA_HAVE_COPROCESSORS
+
+/*
+ * Macros for lazy context switch. 
+ */
+
+#define SAVE_CP_REGS(x)							\
+	.align 4;							\
+	.Lsave_cp_regs_cp##x:						\
+	.if XTENSA_HAVE_COPROCESSOR(x);					\
+		xchal_cp##x##_store a2 a4 a5 a6 a7;			\
+	.endif;								\
+	jx	a0
+
+#define SAVE_CP_REGS_TAB(x)						\
+	.if XTENSA_HAVE_COPROCESSOR(x);					\
+		.long .Lsave_cp_regs_cp##x - .Lsave_cp_regs_jump_table;	\
+	.else;								\
+		.long 0;						\
+	.endif;								\
+	.long THREAD_XTREGS_CP##x
+
+
+#define LOAD_CP_REGS(x)							\
+	.align 4;							\
+	.Lload_cp_regs_cp##x:						\
+	.if XTENSA_HAVE_COPROCESSOR(x);					\
+		xchal_cp##x##_load a2 a4 a5 a6 a7;			\
+	.endif;								\
+	jx	a0
+
+#define LOAD_CP_REGS_TAB(x)						\
+	.if XTENSA_HAVE_COPROCESSOR(x);					\
+		.long .Lload_cp_regs_cp##x - .Lload_cp_regs_jump_table; \
+	.else;								\
+		.long 0;						\
+	.endif;								\
+	.long THREAD_XTREGS_CP##x
+
+	SAVE_CP_REGS(0)
+	SAVE_CP_REGS(1)
+	SAVE_CP_REGS(2)
+	SAVE_CP_REGS(3)
+	SAVE_CP_REGS(4)
+	SAVE_CP_REGS(5)
+	SAVE_CP_REGS(6)
+	SAVE_CP_REGS(7)
+
+	LOAD_CP_REGS(0)
+	LOAD_CP_REGS(1)
+	LOAD_CP_REGS(2)
+	LOAD_CP_REGS(3)
+	LOAD_CP_REGS(4)
+	LOAD_CP_REGS(5)
+	LOAD_CP_REGS(6)
+	LOAD_CP_REGS(7)
+
+	.align 4
+.Lsave_cp_regs_jump_table:
+	SAVE_CP_REGS_TAB(0)
+	SAVE_CP_REGS_TAB(1)
+	SAVE_CP_REGS_TAB(2)
+	SAVE_CP_REGS_TAB(3)
+	SAVE_CP_REGS_TAB(4)
+	SAVE_CP_REGS_TAB(5)
+	SAVE_CP_REGS_TAB(6)
+	SAVE_CP_REGS_TAB(7)
+
+.Lload_cp_regs_jump_table:
+	LOAD_CP_REGS_TAB(0)
+	LOAD_CP_REGS_TAB(1)
+	LOAD_CP_REGS_TAB(2)
+	LOAD_CP_REGS_TAB(3)
+	LOAD_CP_REGS_TAB(4)
+	LOAD_CP_REGS_TAB(5)
+	LOAD_CP_REGS_TAB(6)
+	LOAD_CP_REGS_TAB(7)
+
+/*
+ * coprocessor_save(buffer, index) 
+ *                    a2      a3
+ * coprocessor_load(buffer, index)
+ *                    a2      a3
+ *
+ * Save or load coprocessor registers for coprocessor 'index'. 
+ * The register values are saved to or loaded from them 'buffer' address.
+ *
+ * Note that these functions don't update the coprocessor_owner information!
+ *
+ */
+
+ENTRY(coprocessor_save)
+
+	entry	a1, 32
+	s32i	a0, a1, 0
+	movi	a0, .Lsave_cp_regs_jump_table
+	addx8	a3, a3, a0
+	l32i	a3, a3, 0
+	beqz	a3, 1f
+	add	a0, a0, a3
+	callx0	a0
+1:	l32i	a0, a1, 0
+	retw
+
+ENDPROC(coprocessor_save)
+
+ENTRY(coprocessor_load)
+
+	entry	a1, 32
+	s32i	a0, a1, 0
+	movi	a0, .Lload_cp_regs_jump_table
+	addx4	a3, a3, a0
+	l32i	a3, a3, 0
+	beqz	a3, 1f
+	add	a0, a0, a3
+	callx0	a0
+1:	l32i	a0, a1, 0
+	retw
+
+ENDPROC(coprocessor_load)
+
+/*
+ * coprocessor_flush(struct task_info*, index)
+ *                             a2        a3
+ * coprocessor_restore(struct task_info*, index)
+ *                              a2         a3
+ *
+ * Save or load coprocessor registers for coprocessor 'index'. 
+ * The register values are saved to or loaded from the coprocessor area 
+ * inside the task_info structure.
+ *
+ * Note that these functions don't update the coprocessor_owner information!
+ *
+ */
+
+
+ENTRY(coprocessor_flush)
+
+	entry	a1, 32
+	s32i	a0, a1, 0
+	movi	a0, .Lsave_cp_regs_jump_table
+	addx8	a3, a3, a0
+	l32i	a4, a3, 4
+	l32i	a3, a3, 0
+	add	a2, a2, a4
+	beqz	a3, 1f
+	add	a0, a0, a3
+	callx0	a0
+1:	l32i	a0, a1, 0
+	retw
+
+ENDPROC(coprocessor_flush)
+
+ENTRY(coprocessor_restore)
+	entry	a1, 32
+	s32i	a0, a1, 0
+	movi	a0, .Lload_cp_regs_jump_table
+	addx4	a3, a3, a0
+	l32i	a4, a3, 4
+	l32i	a3, a3, 0
+	add	a2, a2, a4
+	beqz	a3, 1f
+	add	a0, a0, a3
+	callx0	a0
+1:	l32i	a0, a1, 0
+	retw
+
+ENDPROC(coprocessor_restore)
+
+/*
+ * Entry condition:
+ *
+ *   a0:	trashed, original value saved on stack (PT_AREG0)
+ *   a1:	a1
+ *   a2:	new stack pointer, original in DEPC
+ *   a3:	a3
+ *   depc:	a2, original value saved on stack (PT_DEPC)
+ *   excsave_1:	dispatch table
+ *
+ *   PT_DEPC >= VALID_DOUBLE_EXCEPTION_ADDRESS: double exception, DEPC
+ *	     <  VALID_DOUBLE_EXCEPTION_ADDRESS: regular exception
+ */
+
+ENTRY(fast_coprocessor_double)
+
+	wsr	a0, excsave1
+	movi	a0, unrecoverable_exception
+	callx0	a0
+
+ENDPROC(fast_coprocessor_double)
+
+ENTRY(fast_coprocessor)
+
+	/* Save remaining registers a1-a3 and SAR */
+
+	s32i	a3, a2, PT_AREG3
+	rsr	a3, sar
+	s32i	a1, a2, PT_AREG1
+	s32i	a3, a2, PT_SAR
+	mov	a1, a2
+	rsr	a2, depc
+	s32i	a2, a1, PT_AREG2
+
+	/*
+	 * The hal macros require up to 4 temporary registers. We use a3..a6.
+	 */
+
+	s32i	a4, a1, PT_AREG4
+	s32i	a5, a1, PT_AREG5
+	s32i	a6, a1, PT_AREG6
+
+	/* Find coprocessor number. Subtract first CP EXCCAUSE from EXCCAUSE */
+
+	rsr	a3, exccause
+	addi	a3, a3, -EXCCAUSE_COPROCESSOR0_DISABLED
+
+	/* Set corresponding CPENABLE bit -> (sar:cp-index, a3: 1<<cp-index)*/
+
+	ssl	a3			# SAR: 32 - coprocessor_number
+	movi	a2, 1
+	rsr	a0, cpenable
+	sll	a2, a2
+	or	a0, a0, a2
+	wsr	a0, cpenable
+	rsync
+
+	/* Retrieve previous owner. (a3 still holds CP number) */
+
+	movi	a0, coprocessor_owner	# list of owners
+	addx4	a0, a3, a0		# entry for CP
+	l32i	a4, a0, 0
+
+	beqz	a4, 1f			# skip 'save' if no previous owner
+
+	/* Disable coprocessor for previous owner. (a2 = 1 << CP number) */
+
+	l32i	a5, a4, THREAD_CPENABLE
+	xor	a5, a5, a2		# (1 << cp-id) still in a2
+	s32i	a5, a4, THREAD_CPENABLE
+
+	/*
+	 * Get context save area and 'call' save routine. 
+	 * (a4 still holds previous owner (thread_info), a3 CP number)
+	 */
+
+	movi	a5, .Lsave_cp_regs_jump_table
+	movi	a0, 2f			# a0: 'return' address
+	addx8	a3, a3, a5		# a3: coprocessor number
+	l32i	a2, a3, 4		# a2: xtregs offset
+	l32i	a3, a3, 0		# a3: jump offset
+	add	a2, a2, a4
+	add	a4, a3, a5		# a4: address of save routine
+	jx	a4
+
+	/* Note that only a0 and a1 were preserved. */
+
+2:	rsr	a3, exccause
+	addi	a3, a3, -EXCCAUSE_COPROCESSOR0_DISABLED
+	movi	a0, coprocessor_owner
+	addx4	a0, a3, a0
+
+	/* Set new 'owner' (a0 points to the CP owner, a3 contains the CP nr) */
+
+1:	GET_THREAD_INFO (a4, a1)
+	s32i	a4, a0, 0
+
+	/* Get context save area and 'call' load routine. */
+
+	movi	a5, .Lload_cp_regs_jump_table
+	movi	a0, 1f
+	addx8	a3, a3, a5
+	l32i	a2, a3, 4		# a2: xtregs offset
+	l32i	a3, a3, 0		# a3: jump offset
+	add	a2, a2, a4
+	add	a4, a3, a5
+	jx	a4
+
+	/* Restore all registers and return from exception handler. */
+
+1:	l32i	a6, a1, PT_AREG6
+	l32i	a5, a1, PT_AREG5
+	l32i	a4, a1, PT_AREG4
+
+	l32i	a0, a1, PT_SAR
+	l32i	a3, a1, PT_AREG3
+	l32i	a2, a1, PT_AREG2
+	wsr	a0, sar
+	l32i	a0, a1, PT_AREG0
+	l32i	a1, a1, PT_AREG1
+
+	rfe
+
+ENDPROC(fast_coprocessor)
+
+	.data
+
+ENTRY(coprocessor_owner)
+
+	.fill XCHAL_CP_MAX, 4, 0
+
+END(coprocessor_owner)
+
+#endif /* XTENSA_HAVE_COPROCESSORS */