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/*
* include/asm-xtensa/asmmacro.h
*
* 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) 2005 Tensilica Inc.
*/
#ifndef _XTENSA_ASMMACRO_H
#define _XTENSA_ASMMACRO_H
#include <asm/core.h>
/*
* Some little helpers for loops. Use zero-overhead-loops
* where applicable and if supported by the processor.
*
* __loopi ar, at, size, inc
* ar register initialized with the start address
* at scratch register used by macro
* size size immediate value
* inc increment
*
* __loops ar, as, at, inc_log2[, mask_log2][, cond][, ncond]
* ar register initialized with the start address
* as register initialized with the size
* at scratch register use by macro
* inc_log2 increment [in log2]
* mask_log2 mask [in log2]
* cond true condition (used in loop'cond')
* ncond false condition (used in b'ncond')
*
* __loop as
* restart loop. 'as' register must not have been modified!
*
* __endla ar, as, incr
* ar start address (modified)
* as scratch register used by __loops/__loopi macros or
* end address used by __loopt macro
* inc increment
*/
/*
* loop for given size as immediate
*/
.macro __loopi ar, at, size, incr
#if XCHAL_HAVE_LOOPS
movi \at, ((\size + \incr - 1) / (\incr))
loop \at, 99f
#else
addi \at, \ar, \size
98:
#endif
.endm
/*
* loop for given size in register
*/
.macro __loops ar, as, at, incr_log2, mask_log2, cond, ncond
#if XCHAL_HAVE_LOOPS
.ifgt \incr_log2 - 1
addi \at, \as, (1 << \incr_log2) - 1
.ifnc \mask_log2,
extui \at, \at, \incr_log2, \mask_log2
.else
srli \at, \at, \incr_log2
.endif
.endif
loop\cond \at, 99f
#else
.ifnc \mask_log2,
extui \at, \as, \incr_log2, \mask_log2
.else
.ifnc \ncond,
srli \at, \as, \incr_log2
.endif
.endif
.ifnc \ncond,
b\ncond \at, 99f
.endif
.ifnc \mask_log2,
slli \at, \at, \incr_log2
add \at, \ar, \at
.else
add \at, \ar, \as
.endif
#endif
98:
.endm
/*
* loop from ar to as
*/
.macro __loopt ar, as, at, incr_log2
#if XCHAL_HAVE_LOOPS
sub \at, \as, \ar
.ifgt \incr_log2 - 1
addi \at, \at, (1 << \incr_log2) - 1
srli \at, \at, \incr_log2
.endif
loop \at, 99f
#else
98:
#endif
.endm
/*
* restart loop. registers must be unchanged
*/
.macro __loop as
#if XCHAL_HAVE_LOOPS
loop \as, 99f
#else
98:
#endif
.endm
/*
* end of loop with no increment of the address.
*/
.macro __endl ar, as
#if !XCHAL_HAVE_LOOPS
bltu \ar, \as, 98b
#endif
99:
.endm
/*
* end of loop with increment of the address.
*/
.macro __endla ar, as, incr
addi \ar, \ar, \incr
__endl \ar \as
.endm
/* Load or store instructions that may cause exceptions use the EX macro. */
#define EX(handler) \
.section __ex_table, "a"; \
.word 97f, handler; \
.previous \
97:
/*
* Extract unaligned word that is split between two registers w0 and w1
* into r regardless of machine endianness. SAR must be loaded with the
* starting bit of the word (see __ssa8).
*/
.macro __src_b r, w0, w1
#ifdef __XTENSA_EB__
src \r, \w0, \w1
#else
src \r, \w1, \w0
#endif
.endm
/*
* Load 2 lowest address bits of r into SAR for __src_b to extract unaligned
* word starting at r from two registers loaded from consecutive aligned
* addresses covering r regardless of machine endianness.
*
* r 0 1 2 3
* LE SAR 0 8 16 24
* BE SAR 32 24 16 8
*/
.macro __ssa8 r
#ifdef __XTENSA_EB__
ssa8b \r
#else
ssa8l \r
#endif
.endm
#define XTENSA_STACK_ALIGNMENT 16
#if defined(__XTENSA_WINDOWED_ABI__)
#define XTENSA_FRAME_SIZE_RESERVE 16
#define XTENSA_SPILL_STACK_RESERVE 32
#define abi_entry(frame_size) \
entry sp, (XTENSA_FRAME_SIZE_RESERVE + \
(((frame_size) + XTENSA_STACK_ALIGNMENT - 1) & \
-XTENSA_STACK_ALIGNMENT))
#define abi_entry_default abi_entry(0)
#define abi_ret(frame_size) retw
#define abi_ret_default retw
#elif defined(__XTENSA_CALL0_ABI__)
#define XTENSA_SPILL_STACK_RESERVE 0
#define abi_entry(frame_size) __abi_entry (frame_size)
.macro __abi_entry frame_size
.ifgt \frame_size
addi sp, sp, -(((\frame_size) + XTENSA_STACK_ALIGNMENT - 1) & \
-XTENSA_STACK_ALIGNMENT)
.endif
.endm
#define abi_entry_default
#define abi_ret(frame_size) __abi_ret (frame_size)
.macro __abi_ret frame_size
.ifgt \frame_size
addi sp, sp, (((\frame_size) + XTENSA_STACK_ALIGNMENT - 1) & \
-XTENSA_STACK_ALIGNMENT)
.endif
ret
.endm
#define abi_ret_default ret
#else
#error Unsupported Xtensa ABI
#endif
#define __XTENSA_HANDLER .section ".exception.text", "ax"
#endif /* _XTENSA_ASMMACRO_H */
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