[PATCH] xtensa: Architecture support for Tensilica Xtensa Part 3

The attached patches provides part 3 of an architecture implementation for the
Tensilica Xtensa CPU series.

Signed-off-by: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 201 insertions, 0 deletions

diff --git a/arch/xtensa/kernel/coprocessor.S b/arch/xtensa/kernel/coprocessor.S
new file mode 100644
index 0000000..356192a
--- /dev/null
+++ b/arch/xtensa/kernel/coprocessor.S
@@ -0,0 +1,201 @@
+/*
+ * 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 - 2005 Tensilica Inc.
+ *
+ * Marc Gauthier <marc@tensilica.com> <marc@alumni.uwaterloo.ca>
+ */
+
+/*
+ * This module contains a table that describes the layout of the various
+ * custom registers and states associated with each coprocessor, as well
+ * as those not associated with any coprocessor ("extra state").
+ * This table is included with core dumps and is available via the ptrace
+ * interface, allowing the layout of such register/state information to
+ * be modified in the kernel without affecting the debugger.  Each
+ * register or state is identified using a 32-bit "libdb target number"
+ * assigned when the Xtensa processor is generated.
+ */
+
+#include <linux/config.h>
+#include <linux/linkage.h>
+#include <asm/processor.h>
+
+#if XCHAL_HAVE_CP
+
+#define CP_LAST ((XCHAL_CP_MAX - 1) * COPROCESSOR_INFO_SIZE)
+
+ENTRY(release_coprocessors)
+
+	entry	a1, 16
+						# a2: task
+	movi	a3, 1 << XCHAL_CP_MAX 		# a3: coprocessor-bit
+	movi	a4, coprocessor_info+CP_LAST	# a4: owner-table
+						# a5: tmp
+	movi	a6, 0				# a6: 0
+	rsil	a7, LOCKLEVEL			# a7: PS
+
+1:	/* Check if task is coprocessor owner of coprocessor[i]. */
+
+	l32i	a5, a4, COPROCESSOR_INFO_OWNER
+	srli	a3, a3, 1
+	beqz	a3, 1f
+	addi	a4, a4, -8
+	beq	a2, a5, 1b
+
+	/* Found an entry: Clear entry CPENABLE bit to disable CP. */
+
+	rsr	a5, CPENABLE
+	s32i	a6, a4, COPROCESSOR_INFO_OWNER
+	xor	a5, a3, a5
+	wsr	a5, CPENABLE
+
+	bnez	a3, 1b
+
+1:	wsr	a7, PS
+	rsync
+	retw
+
+
+ENTRY(disable_coprocessor)
+	entry	sp, 16
+	rsil	a7, LOCKLEVEL
+	rsr	a3, CPENABLE
+	movi	a4, 1
+	ssl	a2
+	sll	a4, a4
+	and	a4, a3, a4
+	xor	a3, a3, a4
+	wsr	a3, CPENABLE
+	wsr	a7, PS
+	rsync
+	retw
+
+ENTRY(enable_coprocessor)
+	entry	sp, 16
+	rsil	a7, LOCKLEVEL
+	rsr	a3, CPENABLE
+	movi	a4, 1
+	ssl	a2
+	sll	a4, a4
+	or	a3, a3, a4
+	wsr	a3, CPENABLE
+	wsr	a7, PS
+	rsync
+	retw
+
+#endif
+
+ENTRY(save_coprocessor_extra)
+	entry	sp, 16
+	xchal_extra_store_funcbody
+	retw
+
+ENTRY(restore_coprocessor_extra)
+	entry	sp, 16
+	xchal_extra_load_funcbody
+	retw
+
+ENTRY(save_coprocessor_registers)
+	entry	sp, 16
+	xchal_cpi_store_funcbody
+	retw
+
+ENTRY(restore_coprocessor_registers)
+	entry	sp, 16
+	xchal_cpi_load_funcbody
+	retw
+
+
+/*
+ *  The Xtensa compile-time HAL (core.h) XCHAL_*_SA_CONTENTS_LIBDB macros
+ *  describe the contents of coprocessor & extra save areas in terms of
+ *  undefined CONTENTS_LIBDB_{SREG,UREG,REGF} macros.  We define these
+ *  latter macros here; they expand into a table of the format we want.
+ *  The general format is:
+ *
+ *	CONTENTS_LIBDB_SREG(libdbnum, offset, size, align, rsv1, name, sregnum,
+ *			    bitmask, rsv2, rsv3)
+ *	CONTENTS_LIBDB_UREG(libdbnum, offset, size, align, rsv1, name, uregnum,
+ *			    bitmask, rsv2, rsv3)
+ *	CONTENTS_LIBDB_REGF(libdbnum, offset, size, align, rsv1, name, index,
+ *			    numentries, contentsize, regname_base,
+ *			    regfile_name, rsv2, rsv3)
+ *
+ *  For this table, we only care about the <libdbnum>, <offset> and <size>
+ *  fields.
+ */
+
+/*  Map all XCHAL CONTENTS macros to the reg_entry asm macro defined below:  */
+
+#define CONTENTS_LIBDB_SREG(libdbnum,offset,size,align,rsv1,name,sregnum,     \
+			    bitmask, rsv2, rsv3)			      \
+		reg_entry libdbnum, offset, size ;
+#define CONTENTS_LIBDB_UREG(libdbnum,offset,size,align,rsv1,name,uregnum,     \
+			    bitmask, rsv2, rsv3)			      \
+		reg_entry libdbnum, offset, size ;
+#define CONTENTS_LIBDB_REGF(libdbnum, offset, size, align, rsv1, name, index, \
+			    numentries, contentsize, regname_base,	      \
+			    regfile_name, rsv2, rsv3)			      \
+		reg_entry libdbnum, offset, size ;
+
+/* A single table entry: */
+	.macro	reg_entry	libdbnum, offset, size
+	 .ifne	(__last_offset-(__last_group_offset+\offset))
+	  /* padding entry */
+	  .word	(0xFC000000+__last_offset-(__last_group_offset+\offset))
+	 .endif
+	 .word	\libdbnum				/* actual entry */
+	 .set	__last_offset, __last_group_offset+\offset+\size
+	.endm	/* reg_entry */
+
+
+/* Table entry that marks the beginning of a group (coprocessor or "extra"): */
+	.macro	reg_group	cpnum, num_entries, align
+	 .set	__last_group_offset, (__last_offset + \align- 1) & -\align
+	 .ifne	\num_entries
+	  .word	0xFD000000+(\cpnum<<16)+\num_entries
+	 .endif
+	.endm	/* reg_group */
+
+/*
+ * Register info tables.
+ */
+
+	.section .rodata, "a"
+	.globl	_xtensa_reginfo_tables
+	.globl	_xtensa_reginfo_table_size
+	.align	4
+_xtensa_reginfo_table_size:
+	.word	_xtensa_reginfo_table_end - _xtensa_reginfo_tables
+
+_xtensa_reginfo_tables:
+	.set	__last_offset, 0
+	reg_group 0xFF, XCHAL_EXTRA_SA_CONTENTS_LIBDB_NUM, XCHAL_EXTRA_SA_ALIGN
+	XCHAL_EXTRA_SA_CONTENTS_LIBDB
+	reg_group 0, XCHAL_CP0_SA_CONTENTS_LIBDB_NUM, XCHAL_CP0_SA_ALIGN
+	XCHAL_CP0_SA_CONTENTS_LIBDB
+	reg_group 1, XCHAL_CP1_SA_CONTENTS_LIBDB_NUM, XCHAL_CP1_SA_ALIGN
+	XCHAL_CP1_SA_CONTENTS_LIBDB
+	reg_group 2, XCHAL_CP2_SA_CONTENTS_LIBDB_NUM, XCHAL_CP2_SA_ALIGN
+	XCHAL_CP2_SA_CONTENTS_LIBDB
+	reg_group 3, XCHAL_CP3_SA_CONTENTS_LIBDB_NUM, XCHAL_CP3_SA_ALIGN
+	XCHAL_CP3_SA_CONTENTS_LIBDB
+	reg_group 4, XCHAL_CP4_SA_CONTENTS_LIBDB_NUM, XCHAL_CP4_SA_ALIGN
+	XCHAL_CP4_SA_CONTENTS_LIBDB
+	reg_group 5, XCHAL_CP5_SA_CONTENTS_LIBDB_NUM, XCHAL_CP5_SA_ALIGN
+	XCHAL_CP5_SA_CONTENTS_LIBDB
+	reg_group 6, XCHAL_CP6_SA_CONTENTS_LIBDB_NUM, XCHAL_CP6_SA_ALIGN
+	XCHAL_CP6_SA_CONTENTS_LIBDB
+	reg_group 7, XCHAL_CP7_SA_CONTENTS_LIBDB_NUM, XCHAL_CP7_SA_ALIGN
+	XCHAL_CP7_SA_CONTENTS_LIBDB
+	.word	0xFC000000	/* invalid register number,marks end of table*/
+_xtensa_reginfo_table_end:
+