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mangle-port.h
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1 /*
2  * SH version cribbed from the MIPS copy:
3  *
4  * This file is subject to the terms and conditions of the GNU General Public
5  * License. See the file "COPYING" in the main directory of this archive
6  * for more details.
7  *
8  * Copyright (C) 2003, 2004 Ralf Baechle
9  */
10 #ifndef __MACH_COMMON_MANGLE_PORT_H
11 #define __MACH_COMMON_MANGLE_PORT_H
12 
13 /*
14  * Sane hardware offers swapping of PCI/ISA I/O space accesses in hardware;
15  * less sane hardware forces software to fiddle with this...
16  *
17  * Regardless, if the host bus endianness mismatches that of PCI/ISA, then
18  * you can't have the numerical value of data and byte addresses within
19  * multibyte quantities both preserved at the same time. Hence two
20  * variations of functions: non-prefixed ones that preserve the value
21  * and prefixed ones that preserve byte addresses. The latters are
22  * typically used for moving raw data between a peripheral and memory (cf.
23  * string I/O functions), hence the "__mem_" prefix.
24  */
25 #if defined(CONFIG_SWAP_IO_SPACE)
26 
27 # define ioswabb(x) (x)
28 # define __mem_ioswabb(x) (x)
29 # define ioswabw(x) le16_to_cpu(x)
30 # define __mem_ioswabw(x) (x)
31 # define ioswabl(x) le32_to_cpu(x)
32 # define __mem_ioswabl(x) (x)
33 # define ioswabq(x) le64_to_cpu(x)
34 # define __mem_ioswabq(x) (x)
35 
36 #else
37 
38 # define ioswabb(x) (x)
39 # define __mem_ioswabb(x) (x)
40 # define ioswabw(x) (x)
41 # define __mem_ioswabw(x) cpu_to_le16(x)
42 # define ioswabl(x) (x)
43 # define __mem_ioswabl(x) cpu_to_le32(x)
44 # define ioswabq(x) (x)
45 # define __mem_ioswabq(x) cpu_to_le32(x)
46 
47 #endif
48 
49 #endif /* __MACH_COMMON_MANGLE_PORT_H */