kernel-ark/include/asm-mips/mach-generic/mangle-port.h
Atsushi Nemoto a8433137ea [MIPS] Make I/O helpers more customizable
1. Move ioswab*() and __mem_ioswab*() to mangle-port.h.  This gets rid
   of CONFIG_SGI_IP22 from include/asm-mips/io.h.
    
2. Pass a virtual address to *ioswab*().  Then we can provide
   mach-specific *ioswab*() and can do every evil thing based on its
   argument.  It could be useful on machines which have regions with
   different endian conversion scheme.
    
3. Call __swizzle_addr*() _after_ adding mips_io_port_base.  This
   unifies the meaning of the argument of __swizzle_addr*() (always
   virtual address).  Then mach-specific __swizzle_addr*() can do every
   evil thing based on the argument.
    
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-03-21 13:27:45 +00:00

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1.7 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2003, 2004 Ralf Baechle
*/
#ifndef __ASM_MACH_GENERIC_MANGLE_PORT_H
#define __ASM_MACH_GENERIC_MANGLE_PORT_H
#define __swizzle_addr_b(port) (port)
#define __swizzle_addr_w(port) (port)
#define __swizzle_addr_l(port) (port)
#define __swizzle_addr_q(port) (port)
/*
* Sane hardware offers swapping of PCI/ISA I/O space accesses in hardware;
* less sane hardware forces software to fiddle with this...
*
* Regardless, if the host bus endianness mismatches that of PCI/ISA, then
* you can't have the numerical value of data and byte addresses within
* multibyte quantities both preserved at the same time. Hence two
* variations of functions: non-prefixed ones that preserve the value
* and prefixed ones that preserve byte addresses. The latters are
* typically used for moving raw data between a peripheral and memory (cf.
* string I/O functions), hence the "__mem_" prefix.
*/
#if defined(CONFIG_SWAP_IO_SPACE)
# define ioswabb(a,x) (x)
# define __mem_ioswabb(a,x) (x)
# define ioswabw(a,x) le16_to_cpu(x)
# define __mem_ioswabw(a,x) (x)
# define ioswabl(a,x) le32_to_cpu(x)
# define __mem_ioswabl(a,x) (x)
# define ioswabq(a,x) le64_to_cpu(x)
# define __mem_ioswabq(a,x) (x)
#else
# define ioswabb(a,x) (x)
# define __mem_ioswabb(a,x) (x)
# define ioswabw(a,x) (x)
# define __mem_ioswabw(a,x) cpu_to_le16(x)
# define ioswabl(a,x) (x)
# define __mem_ioswabl(a,x) cpu_to_le32(x)
# define ioswabq(a,x) (x)
# define __mem_ioswabq(a,x) cpu_to_le32(x)
#endif
#endif /* __ASM_MACH_GENERIC_MANGLE_PORT_H */