| /* |
| * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| * vineetg: May 2011 |
| * -Support single cycle endian-swap insn in ARC700 4.10 |
| * |
| * vineetg: June 2009 |
| * -Better htonl implementation (5 instead of 9 ALU instructions) |
| * -Hardware assisted single cycle bswap (Use Case of ARC custom instrn) |
| */ |
| |
| #ifndef __ASM_ARC_SWAB_H |
| #define __ASM_ARC_SWAB_H |
| |
| #include <linux/types.h> |
| |
| /* Native single cycle endian swap insn */ |
| #ifdef CONFIG_ARC_HAS_SWAPE |
| |
| #define __arch_swab32(x) \ |
| ({ \ |
| unsigned int tmp = x; \ |
| __asm__( \ |
| " swape %0, %1 \n" \ |
| : "=r" (tmp) \ |
| : "r" (tmp)); \ |
| tmp; \ |
| }) |
| |
| #else |
| |
| /* Several ways of Endian-Swap Emulation for ARC |
| * 0: kernel generic |
| * 1: ARC optimised "C" |
| * 2: ARC Custom instruction |
| */ |
| #define ARC_BSWAP_TYPE 1 |
| |
| #if (ARC_BSWAP_TYPE == 1) /******* Software only ********/ |
| |
| /* The kernel default implementation of htonl is |
| * return x<<24 | x>>24 | |
| * (x & (__u32)0x0000ff00UL)<<8 | (x & (__u32)0x00ff0000UL)>>8; |
| * |
| * This generates 9 instructions on ARC (excluding the ld/st) |
| * |
| * 8051fd8c: ld r3,[r7,20] ; Mem op : Get the value to be swapped |
| * 8051fd98: asl r5,r3,24 ; get 3rd Byte |
| * 8051fd9c: lsr r2,r3,24 ; get 0th Byte |
| * 8051fda0: and r4,r3,0xff00 |
| * 8051fda8: asl r4,r4,8 ; get 1st Byte |
| * 8051fdac: and r3,r3,0x00ff0000 |
| * 8051fdb4: or r2,r2,r5 ; combine 0th and 3rd Bytes |
| * 8051fdb8: lsr r3,r3,8 ; 2nd Byte at correct place in Dst Reg |
| * 8051fdbc: or r2,r2,r4 ; combine 0,3 Bytes with 1st Byte |
| * 8051fdc0: or r2,r2,r3 ; combine 0,3,1 Bytes with 2nd Byte |
| * 8051fdc4: st r2,[r1,20] ; Mem op : save result back to mem |
| * |
| * Joern suggested a better "C" algorithm which is great since |
| * (1) It is portable to any architecure |
| * (2) At the same time it takes advantage of ARC ISA (rotate intrns) |
| */ |
| |
| #define __arch_swab32(x) \ |
| ({ unsigned long __in = (x), __tmp; \ |
| __tmp = __in << 8 | __in >> 24; /* ror tmp,in,24 */ \ |
| __in = __in << 24 | __in >> 8; /* ror in,in,8 */ \ |
| __tmp ^= __in; \ |
| __tmp &= 0xff00ff; \ |
| __tmp ^ __in; \ |
| }) |
| |
| #elif (ARC_BSWAP_TYPE == 2) /* Custom single cycle bswap instruction */ |
| |
| #define __arch_swab32(x) \ |
| ({ \ |
| unsigned int tmp = x; \ |
| __asm__( \ |
| " .extInstruction bswap, 7, 0x00, SUFFIX_NONE, SYNTAX_2OP \n"\ |
| " bswap %0, %1 \n"\ |
| : "=r" (tmp) \ |
| : "r" (tmp)); \ |
| tmp; \ |
| }) |
| |
| #endif /* ARC_BSWAP_TYPE=zzz */ |
| |
| #endif /* CONFIG_ARC_HAS_SWAPE */ |
| |
| #if !defined(__STRICT_ANSI__) || defined(__KERNEL__) |
| #define __SWAB_64_THRU_32__ |
| #endif |
| |
| #endif |
