diff options
Diffstat (limited to 'kernel/arch/blackfin/lib/memset.S')
-rw-r--r-- | kernel/arch/blackfin/lib/memset.S | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/kernel/arch/blackfin/lib/memset.S b/kernel/arch/blackfin/lib/memset.S new file mode 100644 index 000000000..cdcf9148e --- /dev/null +++ b/kernel/arch/blackfin/lib/memset.S @@ -0,0 +1,87 @@ +/* + * Copyright 2004-2009 Analog Devices Inc. + * + * Licensed under the Clear BSD license or the GPL-2 (or later) + */ + +#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. + * The strncpy assumes that I0 and I1 are not used in this function + */ + +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) |