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x86, 386 removal: Remove CONFIG_BSWAP 

All 486+ CPUs support BSWAP, so remove the fallback 386 support
code.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1354132230-21854-5-git-send-email-hpa@linux.intel.com
This commit is contained in:
H. Peter Anvin 2012-11-28 11:50:26 -08:00
parent 7ac468b130
commit e5bb8ad862
4 changed files with 4 additions and 54 deletions
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4
arch/x86/Kconfig.cpu
View File

@ -332,10 +332,6 @@ config X86_INVLPG
def_bool y
depends on X86_32
config X86_BSWAP
def_bool y
depends on X86_32
config X86_POPAD_OK
def_bool y
depends on X86_32

12
arch/x86/include/asm/futex.h
View File

@ -55,12 +55,6 @@ static inline int futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr)
if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
return -EFAULT;
#if defined(CONFIG_X86_32) && !defined(CONFIG_X86_BSWAP)
/* Real i386 machines can only support FUTEX_OP_SET */
if (op != FUTEX_OP_SET && boot_cpu_data.x86 == 3)
return -ENOSYS;
#endif
pagefault_disable();
switch (op) {
@ -118,12 +112,6 @@ static inline int futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
{
int ret = 0;
#if defined(CONFIG_X86_32) && !defined(CONFIG_X86_BSWAP)
/* Real i386 machines have no cmpxchg instruction */
if (boot_cpu_data.x86 == 3)
return -ENOSYS;
#endif
if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
return -EFAULT;

29
arch/x86/include/asm/swab.h
View File

@ -6,22 +6,7 @@
static inline __attribute_const__ __u32 __arch_swab32(__u32 val)
{
#ifdef __i386__
# ifdef CONFIG_X86_BSWAP
asm("bswap %0" : "=r" (val) : "0" (val));
# else
asm("xchgb %b0,%h0\n\t" /* swap lower bytes */
"rorl $16,%0\n\t" /* swap words */
"xchgb %b0,%h0" /* swap higher bytes */
: "=q" (val)
: "0" (val));
# endif
#else /* __i386__ */
asm("bswapl %0"
: "=r" (val)
: "0" (val));
#endif
asm("bswapl %0" : "=r" (val) : "0" (val));
return val;
}
#define __arch_swab32 __arch_swab32
@ -37,22 +22,12 @@ static inline __attribute_const__ __u64 __arch_swab64(__u64 val)
__u64 u;
} v;
v.u = val;
# ifdef CONFIG_X86_BSWAP
asm("bswapl %0 ; bswapl %1 ; xchgl %0,%1"
: "=r" (v.s.a), "=r" (v.s.b)
: "0" (v.s.a), "1" (v.s.b));
# else
v.s.a = __arch_swab32(v.s.a);
v.s.b = __arch_swab32(v.s.b);
asm("xchgl %0,%1"
: "=r" (v.s.a), "=r" (v.s.b)
: "0" (v.s.a), "1" (v.s.b));
# endif
return v.u;
#else /* __i386__ */
asm("bswapq %0"
: "=r" (val)
: "0" (val));
asm("bswapq %0" : "=r" (val) : "0" (val));
return val;
#endif
}

13
arch/x86/kernel/cpu/bugs.c
View File

@ -136,24 +136,15 @@ static void __init check_popad(void)
/*
* Check whether we are able to run this kernel safely on SMP.
*
* - In order to run on a i386, we need to be compiled for i386
* (for due to lack of "invlpg" and working WP on a i386)
* - i386 is no longer supported.
* - In order to run on anything without a TSC, we need to be
* compiled for a i486.
*/
static void __init check_config(void)
{
/*
* We'd better not be a i386 if we're configured to use some
* i486+ only features! (WP works in supervisor mode and the
* new "invlpg" and "bswap" instructions)
*/
#if defined(CONFIG_X86_WP_WORKS_OK) || defined(CONFIG_X86_INVLPG) || \
defined(CONFIG_X86_BSWAP)
if (boot_cpu_data.x86 == 3)
if (boot_cpu_data.x86 < 4)
panic("Kernel requires i486+ for 'invlpg' and other features");
#endif
}