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![Chris Zankel](/assets/img/avatar_default.png)
The header files in the asm-xtensa directory are not clean and 'make headers_check' fails. This is a first patch to fix most of the header files. It removes unnecessary include statements and adds some that are required for building the kernel. The linker script required some updates or the linking stage would fail. Signed-off-by: Chris Zankel <chris@zankel.net>
82 lines
2.4 KiB
C
82 lines
2.4 KiB
C
/*
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* include/asm-xtensa/byteorder.h
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*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*
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* Copyright (C) 2001 - 2005 Tensilica Inc.
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*/
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#ifndef _XTENSA_BYTEORDER_H
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#define _XTENSA_BYTEORDER_H
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#include <asm/types.h>
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#include <linux/compiler.h>
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static __inline__ __attribute_const__ __u32 ___arch__swab32(__u32 x)
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{
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__u32 res;
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/* instruction sequence from Xtensa ISA release 2/2000 */
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__asm__("ssai 8 \n\t"
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"srli %0, %1, 16 \n\t"
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"src %0, %0, %1 \n\t"
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"src %0, %0, %0 \n\t"
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"src %0, %1, %0 \n"
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: "=&a" (res)
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: "a" (x)
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);
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return res;
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}
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static __inline__ __attribute_const__ __u16 ___arch__swab16(__u16 x)
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{
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/* Given that 'short' values are signed (i.e., can be negative),
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* we cannot assume that the upper 16-bits of the register are
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* zero. We are careful to mask values after shifting.
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*/
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/* There exists an anomaly between xt-gcc and xt-xcc. xt-gcc
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* inserts an extui instruction after putting this function inline
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* to ensure that it uses only the least-significant 16 bits of
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* the result. xt-xcc doesn't use an extui, but assumes the
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* __asm__ macro follows convention that the upper 16 bits of an
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* 'unsigned short' result are still zero. This macro doesn't
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* follow convention; indeed, it leaves garbage in the upport 16
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* bits of the register.
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* Declaring the temporary variables 'res' and 'tmp' to be 32-bit
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* types while the return type of the function is a 16-bit type
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* forces both compilers to insert exactly one extui instruction
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* (or equivalent) to mask off the upper 16 bits. */
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__u32 res;
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__u32 tmp;
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__asm__("extui %1, %2, 8, 8\n\t"
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"slli %0, %2, 8 \n\t"
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"or %0, %0, %1 \n"
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: "=&a" (res), "=&a" (tmp)
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: "a" (x)
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);
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return res;
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}
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#define __arch__swab32(x) ___arch__swab32(x)
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#define __arch__swab16(x) ___arch__swab16(x)
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#if !defined(__STRICT_ANSI__) || defined(__KERNEL__)
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# define __BYTEORDER_HAS_U64__
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# define __SWAB_64_THRU_32__
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#endif
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#ifdef __XTENSA_EL__
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# include <linux/byteorder/little_endian.h>
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#elif defined(__XTENSA_EB__)
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# include <linux/byteorder/big_endian.h>
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#else
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# error processor byte order undefined!
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#endif
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#endif /* _XTENSA_BYTEORDER_H */
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