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

4 files changed, 4 insertions, 54 deletions

diff --git a/arch/x86/Kconfig.cpu b/arch/x86/Kconfig.cpu
index 52955eeeb1ef..8e5867cf07d0 100644
--- a/arch/x86/Kconfig.cpu
+++ b/arch/x86/Kconfig.cpu
@@ -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
diff --git a/arch/x86/include/asm/futex.h b/arch/x86/include/asm/futex.h
index f373046e63ec..be27ba1e947a 100644
--- a/arch/x86/include/asm/futex.h
+++ b/arch/x86/include/asm/futex.h
@@ -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;
 
diff --git a/arch/x86/include/asm/swab.h b/arch/x86/include/asm/swab.h
index 557cd9f00661..7f235c7105c1 100644
--- a/arch/x86/include/asm/swab.h
+++ b/arch/x86/include/asm/swab.h
@@ -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
 }
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index d0e910da16c5..0cd07ccdf380 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -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
 }