linux/arch/blackfin/lib/memset.S

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blackfin architecture This adds support for the Analog Devices Blackfin processor architecture, and currently supports the BF533, BF532, BF531, BF537, BF536, BF534, and BF561 (Dual Core) devices, with a variety of development platforms including those avaliable from Analog Devices (BF533-EZKit, BF533-STAMP, BF537-STAMP, BF561-EZKIT), and Bluetechnix! Tinyboards. The Blackfin architecture was jointly developed by Intel and Analog Devices Inc. (ADI) as the Micro Signal Architecture (MSA) core and introduced it in December of 2000. Since then ADI has put this core into its Blackfin processor family of devices. The Blackfin core has the advantages of a clean, orthogonal,RISC-like microprocessor instruction set. It combines a dual-MAC (Multiply/Accumulate), state-of-the-art signal processing engine and single-instruction, multiple-data (SIMD) multimedia capabilities into a single instruction-set architecture. The Blackfin architecture, including the instruction set, is described by the ADSP-BF53x/BF56x Blackfin Processor Programming Reference http://blackfin.uclinux.org/gf/download/frsrelease/29/2549/Blackfin_PRM.pdf The Blackfin processor is already supported by major releases of gcc, and there are binary and source rpms/tarballs for many architectures at: http://blackfin.uclinux.org/gf/project/toolchain/frs There is complete documentation, including "getting started" guides available at: http://docs.blackfin.uclinux.org/ which provides links to the sources and patches you will need in order to set up a cross-compiling environment for bfin-linux-uclibc This patch, as well as the other patches (toolchain, distribution, uClibc) are actively supported by Analog Devices Inc, at: http://blackfin.uclinux.org/ We have tested this on LTP, and our test plan (including pass/fails) can be found at: http://docs.blackfin.uclinux.org/doku.php?id=testing_the_linux_kernel [m.kozlowski@tuxland.pl: balance parenthesis in blackfin header files] Signed-off-by: Bryan Wu <bryan.wu@analog.com> Signed-off-by: Mariusz Kozlowski <m.kozlowski@tuxland.pl> Signed-off-by: Aubrey Li <aubrey.li@analog.com> Signed-off-by: Jie Zhang <jie.zhang@analog.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-06 23:50:22 +02:00
/*
* File: arch/blackfin/lib/memset.S
* Based on:
* Author:
*
* Created:
* Description:
*
* Modified:
* Copyright 2004-2006 Analog Devices Inc.
*
* Bugs: Enter bugs at http://blackfin.uclinux.org/
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see the file COPYING, or write
* to the Free Software Foundation, Inc.,
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <linux/linkage.h>
.align 2
#ifdef CONFIG_MEMSET_L1
.section .l1.text
#else
.text
#endif
/*
* C Library function MEMSET
* R0 = address (leave unchanged to form result)
* R1 = filler byte
* R2 = count
* Favours word aligned data.
*/
ENTRY(_memset)
P0 = R0 ; /* P0 = address */
P2 = R2 ; /* P2 = count */
R3 = R0 + R2; /* end */
CC = R2 <= 7(IU);
IF CC JUMP .Ltoo_small;
R1 = R1.B (Z); /* R1 = fill char */
R2 = 3;
R2 = R0 & R2; /* addr bottom two bits */
CC = R2 == 0; /* AZ set if zero. */
IF !CC JUMP .Lforce_align ; /* Jump if addr not aligned. */
.Laligned:
P1 = P2 >> 2; /* count = n/4 */
R2 = R1 << 8; /* create quad filler */
R2.L = R2.L + R1.L(NS);
R2.H = R2.L + R1.H(NS);
P2 = R3;
LSETUP (.Lquad_loop , .Lquad_loop) LC0=P1;
.Lquad_loop:
[P0++] = R2;
CC = P0 == P2;
IF !CC JUMP .Lbytes_left;
RTS;
.Lbytes_left:
R2 = R3; /* end point */
R3 = P0; /* current position */
R2 = R2 - R3; /* bytes left */
P2 = R2;
.Ltoo_small:
CC = P2 == 0; /* Check zero count */
IF CC JUMP .Lfinished; /* Unusual */
.Lbytes:
LSETUP (.Lbyte_loop , .Lbyte_loop) LC0=P2;
.Lbyte_loop:
B[P0++] = R1;
.Lfinished:
RTS;
.Lforce_align:
CC = BITTST (R0, 0); /* odd byte */
R0 = 4;
R0 = R0 - R2;
P1 = R0;
R0 = P0; /* Recover return address */
IF !CC JUMP .Lskip1;
B[P0++] = R1;
.Lskip1:
CC = R2 <= 2; /* 2 bytes */
P2 -= P1; /* reduce count */
IF !CC JUMP .Laligned;
B[P0++] = R1;
B[P0++] = R1;
JUMP .Laligned;
ENDPROC(_memset)