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Diffstat (limited to 'arch/xtensa/include/asm/asmmacro.h')
| -rw-r--r-- | arch/xtensa/include/asm/asmmacro.h | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/arch/xtensa/include/asm/asmmacro.h b/arch/xtensa/include/asm/asmmacro.h new file mode 100644 index 000000000..7f2ae5872 --- /dev/null +++ b/arch/xtensa/include/asm/asmmacro.h @@ -0,0 +1,194 @@ +/* + * 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 <variant/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 + +#endif /* _XTENSA_ASMMACRO_H */ |