diff options
| -rw-r--r-- | arch/xtensa/include/asm/Kbuild | 2 | ||||
| -rw-r--r-- | arch/xtensa/include/asm/byteorder.h | 72 | ||||
| -rw-r--r-- | arch/xtensa/include/asm/swab.h | 70 |
3 files changed, 75 insertions, 69 deletions
diff --git a/arch/xtensa/include/asm/Kbuild b/arch/xtensa/include/asm/Kbuild index c68e1680da01..58c02a454130 100644 --- a/arch/xtensa/include/asm/Kbuild +++ b/arch/xtensa/include/asm/Kbuild | |||
| @@ -1 +1,3 @@ | |||
| 1 | include include/asm-generic/Kbuild.asm | 1 | include include/asm-generic/Kbuild.asm |
| 2 | |||
| 3 | unifdef-y += swab.h | ||
diff --git a/arch/xtensa/include/asm/byteorder.h b/arch/xtensa/include/asm/byteorder.h index 07d10ad364d1..329b94591ca4 100644 --- a/arch/xtensa/include/asm/byteorder.h +++ b/arch/xtensa/include/asm/byteorder.h | |||
| @@ -1,80 +1,14 @@ | |||
| 1 | /* | ||
| 2 | * include/asm-xtensa/byteorder.h | ||
| 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) 2001 - 2005 Tensilica Inc. | ||
| 9 | */ | ||
| 10 | |||
| 11 | #ifndef _XTENSA_BYTEORDER_H | 1 | #ifndef _XTENSA_BYTEORDER_H |
| 12 | #define _XTENSA_BYTEORDER_H | 2 | #define _XTENSA_BYTEORDER_H |
| 13 | 3 | ||
| 14 | #include <asm/types.h> | 4 | #include <asm/swab.h> |
| 15 | #include <linux/compiler.h> | ||
| 16 | 5 | ||
| 17 | #ifdef __XTENSA_EL__ | 6 | #ifdef __XTENSA_EL__ |
| 18 | # define __LITTLE_ENDIAN | 7 | #include <linux/byteorder/little_endian.h> |
| 19 | #elif defined(__XTENSA_EB__) | 8 | #elif defined(__XTENSA_EB__) |
| 20 | # define __BIG_ENDIAN | 9 | #include <linux/byteorder/big_endian.h> |
| 21 | #else | 10 | #else |
| 22 | # error processor byte order undefined! | 11 | # error processor byte order undefined! |
| 23 | #endif | 12 | #endif |
| 24 | 13 | ||
| 25 | #define __SWAB_64_THRU_32__ | ||
| 26 | |||
| 27 | static inline __attribute_const__ __u32 __arch_swab32(__u32 x) | ||
| 28 | { | ||
| 29 | __u32 res; | ||
| 30 | /* instruction sequence from Xtensa ISA release 2/2000 */ | ||
| 31 | __asm__("ssai 8 \n\t" | ||
| 32 | "srli %0, %1, 16 \n\t" | ||
| 33 | "src %0, %0, %1 \n\t" | ||
| 34 | "src %0, %0, %0 \n\t" | ||
| 35 | "src %0, %1, %0 \n" | ||
| 36 | : "=&a" (res) | ||
| 37 | : "a" (x) | ||
| 38 | ); | ||
| 39 | return res; | ||
| 40 | } | ||
| 41 | #define __arch_swab32 __arch_swab32 | ||
| 42 | |||
| 43 | static inline __attribute_const__ __u16 __arch_swab16(__u16 x) | ||
| 44 | { | ||
| 45 | /* Given that 'short' values are signed (i.e., can be negative), | ||
| 46 | * we cannot assume that the upper 16-bits of the register are | ||
| 47 | * zero. We are careful to mask values after shifting. | ||
| 48 | */ | ||
| 49 | |||
| 50 | /* There exists an anomaly between xt-gcc and xt-xcc. xt-gcc | ||
| 51 | * inserts an extui instruction after putting this function inline | ||
| 52 | * to ensure that it uses only the least-significant 16 bits of | ||
| 53 | * the result. xt-xcc doesn't use an extui, but assumes the | ||
| 54 | * __asm__ macro follows convention that the upper 16 bits of an | ||
| 55 | * 'unsigned short' result are still zero. This macro doesn't | ||
| 56 | * follow convention; indeed, it leaves garbage in the upport 16 | ||
| 57 | * bits of the register. | ||
| 58 | |||
| 59 | * Declaring the temporary variables 'res' and 'tmp' to be 32-bit | ||
| 60 | * types while the return type of the function is a 16-bit type | ||
| 61 | * forces both compilers to insert exactly one extui instruction | ||
| 62 | * (or equivalent) to mask off the upper 16 bits. */ | ||
| 63 | |||
| 64 | __u32 res; | ||
| 65 | __u32 tmp; | ||
| 66 | |||
| 67 | __asm__("extui %1, %2, 8, 8\n\t" | ||
| 68 | "slli %0, %2, 8 \n\t" | ||
| 69 | "or %0, %0, %1 \n" | ||
| 70 | : "=&a" (res), "=&a" (tmp) | ||
| 71 | : "a" (x) | ||
| 72 | ); | ||
| 73 | |||
| 74 | return res; | ||
| 75 | } | ||
| 76 | #define __arch_swab16 __arch_swab16 | ||
| 77 | |||
| 78 | #include <linux/byteorder.h> | ||
| 79 | |||
| 80 | #endif /* _XTENSA_BYTEORDER_H */ | 14 | #endif /* _XTENSA_BYTEORDER_H */ |
diff --git a/arch/xtensa/include/asm/swab.h b/arch/xtensa/include/asm/swab.h new file mode 100644 index 000000000000..f50b697eb601 --- /dev/null +++ b/arch/xtensa/include/asm/swab.h | |||
| @@ -0,0 +1,70 @@ | |||
| 1 | /* | ||
| 2 | * include/asm-xtensa/swab.h | ||
| 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) 2001 - 2005 Tensilica Inc. | ||
| 9 | */ | ||
| 10 | |||
| 11 | #ifndef _XTENSA_SWAB_H | ||
| 12 | #define _XTENSA_SWAB_H | ||
| 13 | |||
| 14 | #include <asm/types.h> | ||
| 15 | #include <linux/compiler.h> | ||
| 16 | |||
| 17 | #define __SWAB_64_THRU_32__ | ||
| 18 | |||
| 19 | static inline __attribute_const__ __u32 __arch_swab32(__u32 x) | ||
| 20 | { | ||
| 21 | __u32 res; | ||
| 22 | /* instruction sequence from Xtensa ISA release 2/2000 */ | ||
| 23 | __asm__("ssai 8 \n\t" | ||
| 24 | "srli %0, %1, 16 \n\t" | ||
| 25 | "src %0, %0, %1 \n\t" | ||
| 26 | "src %0, %0, %0 \n\t" | ||
| 27 | "src %0, %1, %0 \n" | ||
| 28 | : "=&a" (res) | ||
| 29 | : "a" (x) | ||
| 30 | ); | ||
| 31 | return res; | ||
| 32 | } | ||
| 33 | #define __arch_swab32 __arch_swab32 | ||
| 34 | |||
| 35 | static inline __attribute_const__ __u16 __arch_swab16(__u16 x) | ||
| 36 | { | ||
| 37 | /* Given that 'short' values are signed (i.e., can be negative), | ||
| 38 | * we cannot assume that the upper 16-bits of the register are | ||
| 39 | * zero. We are careful to mask values after shifting. | ||
| 40 | */ | ||
| 41 | |||
| 42 | /* There exists an anomaly between xt-gcc and xt-xcc. xt-gcc | ||
| 43 | * inserts an extui instruction after putting this function inline | ||
| 44 | * to ensure that it uses only the least-significant 16 bits of | ||
| 45 | * the result. xt-xcc doesn't use an extui, but assumes the | ||
| 46 | * __asm__ macro follows convention that the upper 16 bits of an | ||
| 47 | * 'unsigned short' result are still zero. This macro doesn't | ||
| 48 | * follow convention; indeed, it leaves garbage in the upport 16 | ||
| 49 | * bits of the register. | ||
| 50 | |||
| 51 | * Declaring the temporary variables 'res' and 'tmp' to be 32-bit | ||
| 52 | * types while the return type of the function is a 16-bit type | ||
| 53 | * forces both compilers to insert exactly one extui instruction | ||
| 54 | * (or equivalent) to mask off the upper 16 bits. */ | ||
| 55 | |||
| 56 | __u32 res; | ||
| 57 | __u32 tmp; | ||
| 58 | |||
| 59 | __asm__("extui %1, %2, 8, 8\n\t" | ||
| 60 | "slli %0, %2, 8 \n\t" | ||
| 61 | "or %0, %0, %1 \n" | ||
| 62 | : "=&a" (res), "=&a" (tmp) | ||
| 63 | : "a" (x) | ||
| 64 | ); | ||
| 65 | |||
| 66 | return res; | ||
| 67 | } | ||
| 68 | #define __arch_swab16 __arch_swab16 | ||
| 69 | |||
| 70 | #endif /* _XTENSA_SWAB_H */ | ||
