1 /* 2 * Copyright 2004-2009 Analog Devices Inc. 3 * 4 * Licensed under the Clear BSD license or the GPL-2 (or later) 5 */ 6 7 #include <linux/linkage.h> 8 9 .align 2 10 11 #ifdef CONFIG_MEMSET_L1 12 .section .l1.text 13 #else 14 .text 15 #endif 16 17 /* 18 * C Library function MEMSET 19 * R0 = address (leave unchanged to form result) 20 * R1 = filler byte 21 * R2 = count 22 * Favours word aligned data. 23 * The strncpy assumes that I0 and I1 are not used in this function 24 */ 25 26 ENTRY(_memset) 27 P0 = R0 ; /* P0 = address */ 28 P2 = R2 ; /* P2 = count */ 29 R3 = R0 + R2; /* end */ 30 CC = R2 <= 7(IU); 31 IF CC JUMP .Ltoo_small; 32 R1 = R1.B (Z); /* R1 = fill char */ 33 R2 = 3; 34 R2 = R0 & R2; /* addr bottom two bits */ 35 CC = R2 == 0; /* AZ set if zero. */ 36 IF !CC JUMP .Lforce_align ; /* Jump if addr not aligned. */ 37 38 .Laligned: 39 P1 = P2 >> 2; /* count = n/4 */ 40 R2 = R1 << 8; /* create quad filler */ 41 R2.L = R2.L + R1.L(NS); 42 R2.H = R2.L + R1.H(NS); 43 P2 = R3; 44 45 LSETUP (.Lquad_loop , .Lquad_loop) LC0=P1; 46 .Lquad_loop: 47 [P0++] = R2; 48 49 CC = P0 == P2; 50 IF !CC JUMP .Lbytes_left; 51 RTS; 52 53 .Lbytes_left: 54 R2 = R3; /* end point */ 55 R3 = P0; /* current position */ 56 R2 = R2 - R3; /* bytes left */ 57 P2 = R2; 58 59 .Ltoo_small: 60 CC = P2 == 0; /* Check zero count */ 61 IF CC JUMP .Lfinished; /* Unusual */ 62 63 .Lbytes: 64 LSETUP (.Lbyte_loop , .Lbyte_loop) LC0=P2; 65 .Lbyte_loop: 66 B[P0++] = R1; 67 68 .Lfinished: 69 RTS; 70 71 .Lforce_align: 72 CC = BITTST (R0, 0); /* odd byte */ 73 R0 = 4; 74 R0 = R0 - R2; 75 P1 = R0; 76 R0 = P0; /* Recover return address */ 77 IF !CC JUMP .Lskip1; 78 B[P0++] = R1; 79 .Lskip1: 80 CC = R2 <= 2; /* 2 bytes */ 81 P2 -= P1; /* reduce count */ 82 IF !CC JUMP .Laligned; 83 B[P0++] = R1; 84 B[P0++] = R1; 85 JUMP .Laligned; 86 87 ENDPROC(_memset) 88
