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[PATCH mini-os enhancements for vtpm 3/8] add endian support to mini-os
This patch addes byte swapping macros and endian support to mini-os

Signed off by: Matthew Fioravante matthew.fioravante@jhuapl.edu

diff --git a/extras/mini-os/include/byteorder.h
b/extras/mini-os/include/byteorder.h
--- /dev/null
+++ b/extras/mini-os/include/byteorder.h
@@ -0,0 +1,36 @@
+#ifndef MINIOS_BYTEORDER_H
+#define MINIOS_BYTEORDER_H
+
+#include <mini-os/byteswap.h>
+#include <mini-os/endian.h>
+
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+#define be16_to_cpu(v) bswap_16(v)
+#define be32_to_cpu(v) bswap_32(v)
+#define be64_to_cpu(v) bswap_64(v)
+
+#define le16_to_cpu(v) (v)
+#define le32_to_cpu(v) (v)
+#define le64_to_cpu(v) (v)
+
+#else /*__BIG_ENDIAN*/
+#define be16_to_cpu(v) (v)
+#define be32_to_cpu(v) (v)
+#define be64_to_cpu(v) (v)
+
+#define le16_to_cpu(v) bswap_16(v)
+#define le32_to_cpu(v) bswap_32(v)
+#define le64_to_cpu(v) bswap_64(v)
+
+#endif
+
+#define cpu_to_be16(v) be16_to_cpu(v)
+#define cpu_to_be32(v) be32_to_cpu(v)
+#define cpu_to_be64(v) be64_to_cpu(v)
+
+#define cpu_to_le16(v) le16_to_cpu(v)
+#define cpu_to_le32(v) le32_to_cpu(v)
+#define cpu_to_le64(v) le64_to_cpu(v)
+
+
+#endif
diff --git a/extras/mini-os/include/byteswap.h
b/extras/mini-os/include/byteswap.h
--- a/extras/mini-os/include/byteswap.h
+++ b/extras/mini-os/include/byteswap.h
@@ -4,30 +4,36 @@
/* Unfortunately not provided by newlib. */

#include <mini-os/types.h>
-static inline uint16_t bswap_16(uint16_t x)
-{
- return
- ((((x) & 0xff00) >> 8) | (((x) & 0xff) << 8));
-}
-
-static inline uint32_t bswap_32(uint32_t x)
-{
- return
- ((((x) & 0xff000000) >> 24) | (((x) & 0x00ff0000) >> 8) |
- (((x) & 0x0000ff00) << 8) | (((x) & 0x000000ff) << 24));
-}
-
-static inline uint64_t bswap_64(uint64_t x)
-{
- return
- ((((x) & 0xff00000000000000ULL) >> 56) |
- (((x) & 0x00ff000000000000ULL) >> 40) |
- (((x) & 0x0000ff0000000000ULL) >> 24) |
- (((x) & 0x000000ff00000000ULL) >> 8) |
- (((x) & 0x00000000ff000000ULL) << 8) |
- (((x) & 0x0000000000ff0000ULL) << 24) |
- (((x) & 0x000000000000ff00ULL) << 40) |
- (((x) & 0x00000000000000ffULL) << 56));
-}
+
+#define bswap_16(x) ((uint16_t)( \
+ (((uint16_t)(x) & (uint16_t)0x00ffU) << 8)
| \
+ (((uint16_t)(x) & (uint16_t)0xff00U) >> 8)))
+
+/* Use gcc optimized versions if they exist */
+#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
+#define bswap_32(v) __builtin_bswap32(v)
+#define bswap_64(v) __builtin_bswap64(v)
+#else
+
+#define bswap_32(x) ((uint32_t)( \
+ (((uint32_t)(x) & (uint32_t)0x000000ffUL) << 24)
| \
+ (((uint32_t)(x) & (uint32_t)0x0000ff00UL) << 8)
| \
+ (((uint32_t)(x) & (uint32_t)0x00ff0000UL) >> 8)
| \
+ (((uint32_t)(x) & (uint32_t)0xff000000UL) >> 24)))
+
+#define bswap_64(x) ((uint64_t)( \
+ (((uint64_t)(x) & (uint64_t)0x00000000000000ffULL) << 56)
| \
+ (((uint64_t)(x) & (uint64_t)0x000000000000ff00ULL) << 40)
| \
+ (((uint64_t)(x) & (uint64_t)0x0000000000ff0000ULL) << 24)
| \
+ (((uint64_t)(x) & (uint64_t)0x00000000ff000000ULL) << 8)
| \
+ (((uint64_t)(x) & (uint64_t)0x000000ff00000000ULL) >> 8)
| \
+ (((uint64_t)(x) & (uint64_t)0x0000ff0000000000ULL) >> 24)
| \
+ (((uint64_t)(x) & (uint64_t)0x00ff000000000000ULL) >> 40)
| \
+ (((uint64_t)(x) & (uint64_t)0xff00000000000000ULL) >> 56)))
+
+#endif
+
+
+

#endif /* _BYTESWAP_H */
diff --git a/extras/mini-os/include/endian.h
b/extras/mini-os/include/endian.h
--- /dev/null
+++ b/extras/mini-os/include/endian.h
@@ -0,0 +1,15 @@
+#ifndef _ENDIAN_H_
+#define _ENDIAN_H_
+
+#define __LITTLE_ENDIAN 1234
+#define __BIG_ENDIAN 4321
+#define __PDP_ENDIAN 3412
+
+#define ARCH_ENDIAN_H
+/* This will define __BYTE_ORDER for the current arch */
+#include <arch_endian.h>
+#undef ARCH_ENDIAN_H
+
+#include <arch_wordsize.h>
+
+#endif /* endian.h */
diff --git a/extras/mini-os/include/ia64/arch_endian.h
b/extras/mini-os/include/ia64/arch_endian.h
--- /dev/null
+++ b/extras/mini-os/include/ia64/arch_endian.h
@@ -0,0 +1,7 @@
+#ifndef ARCH_ENDIAN_H
+#error "Do not include arch_endian by itself, include endian.h"
+#else
+
+#define __BYTE_ORDER __LITTLE_ENDIAN
+
+#endif
diff --git a/extras/mini-os/include/ia64/arch_wordsize.h
b/extras/mini-os/include/ia64/arch_wordsize.h
--- /dev/null
+++ b/extras/mini-os/include/ia64/arch_wordsize.h
@@ -0,0 +1 @@
+#define __WORDSIZE 64
diff --git a/extras/mini-os/include/x86/arch_endian.h
b/extras/mini-os/include/x86/arch_endian.h
--- /dev/null
+++ b/extras/mini-os/include/x86/arch_endian.h
@@ -0,0 +1,7 @@
+#ifndef ARCH_ENDIAN_H
+#error "Do not include arch_endian by itself, include endian.h"
+#else
+
+#define __BYTE_ORDER __LITTLE_ENDIAN
+
+#endif
diff --git a/extras/mini-os/include/x86/x86_32/arch_wordsize.h
b/extras/mini-os/include/x86/x86_32/arch_wordsize.h
--- /dev/null
+++ b/extras/mini-os/include/x86/x86_32/arch_wordsize.h
@@ -0,0 +1 @@
+#define __WORDSIZE 32
diff --git a/extras/mini-os/include/x86/x86_64/arch_wordsize.h
b/extras/mini-os/include/x86/x86_64/arch_wordsize.h
--- /dev/null
+++ b/extras/mini-os/include/x86/x86_64/arch_wordsize.h
@@ -0,0 +1,2 @@
+#define __WORDSIZE 64
+#define __WORDSIZE_COMPAT32 1
Re: [PATCH mini-os enhancements for vtpm 3/8] add endian support to mini-os [ In reply to ]
Matthew Fioravante, le Mon 17 Sep 2012 17:57:11 -0400, a écrit :
> diff --git a/extras/mini-os/include/byteorder.h
> b/extras/mini-os/include/byteorder.h
> --- /dev/null
> +++ b/extras/mini-os/include/byteorder.h

Ok.

> -static inline uint16_t bswap_16(uint16_t x)
> -{
> - return
> - ((((x) & 0xff00) >> 8) | (((x) & 0xff) << 8));
> -}
> -
> +#define bswap_16(x) ((uint16_t)( \
> + (((uint16_t)(x) & (uint16_t)0x00ffU) << 8)
> | \
> + (((uint16_t)(x) & (uint16_t)0xff00U) >> 8)))

Why replacing the inline with a macro? AIUI, inlines provide the same
efficiency while providing some minimal type checking (and safety
against things like bswap_16(x++).

> diff --git a/extras/mini-os/include/endian.h
> diff --git a/extras/mini-os/include/ia64/arch_endian.h
> diff --git a/extras/mini-os/include/ia64/arch_wordsize.h
> diff --git a/extras/mini-os/include/x86/arch_endian.h
> diff --git a/extras/mini-os/include/x86/x86_32/arch_wordsize.h
> diff --git a/extras/mini-os/include/x86/x86_64/arch_wordsize.h

Ok.

Samuel

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Re: [PATCH mini-os enhancements for vtpm 3/8] add endian support to mini-os [ In reply to ]
On 09/17/2012 06:12 PM, Samuel Thibault wrote:
> Matthew Fioravante, le Mon 17 Sep 2012 17:57:11 -0400, a écrit :
>> diff --git a/extras/mini-os/include/byteorder.h
>> b/extras/mini-os/include/byteorder.h
>> --- /dev/null
>> +++ b/extras/mini-os/include/byteorder.h
> Ok.
>
>> -static inline uint16_t bswap_16(uint16_t x)
>> -{
>> - return
>> - ((((x) & 0xff00) >> 8) | (((x) & 0xff) << 8));
>> -}
>> -
>> +#define bswap_16(x) ((uint16_t)( \
>> + (((uint16_t)(x) & (uint16_t)0x00ffU) << 8)
>> | \
>> + (((uint16_t)(x) & (uint16_t)0xff00U) >> 8)))
> Why replacing the inline with a macro? AIUI, inlines provide the same
> efficiency while providing some minimal type checking (and safety
> against things like bswap_16(x++).
With a macro you can do this:

const uint16_t foo = bswap_16(4000);

Not possible with inline. From what I've seen in other system heads
(linux in particular), they tend to be implemented as macros or compiler
builtins.
>
>> diff --git a/extras/mini-os/include/endian.h
>> diff --git a/extras/mini-os/include/ia64/arch_endian.h
>> diff --git a/extras/mini-os/include/ia64/arch_wordsize.h
>> diff --git a/extras/mini-os/include/x86/arch_endian.h
>> diff --git a/extras/mini-os/include/x86/x86_32/arch_wordsize.h
>> diff --git a/extras/mini-os/include/x86/x86_64/arch_wordsize.h
> Ok.
>
> Samuel
Re: [PATCH mini-os enhancements for vtpm 3/8] add endian support to mini-os [ In reply to ]
Matthew Fioravante, le Tue 18 Sep 2012 13:45:08 -0400, a écrit :
> With a macro you can do this:
>
> const uint16_t foo = bswap_16(4000);

Ok, then

Acked-by: Samuel Thibault <samuel.thibault@ens-lyon.org>

Samuel

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