1 files changed, 473 insertions, 0 deletions

diff --git a/include/asm-i386/system.h b/include/asm-i386/system.h
new file mode 100644
index 000000000000..6f74d4c44a0e
--- /dev/null
+++ b/include/asm-i386/system.h
@@ -0,0 +1,473 @@
+#ifndef __ASM_SYSTEM_H
+#define __ASM_SYSTEM_H
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <asm/segment.h>
+#include <asm/cpufeature.h>
+#include <linux/bitops.h> /* for LOCK_PREFIX */
+
+#ifdef __KERNEL__
+
+struct task_struct;     /* one of the stranger aspects of C forward declarations.. */
+extern struct task_struct * FASTCALL(__switch_to(struct task_struct *prev, struct task_struct *next));
+
+#define switch_to(prev,next,last) do {                                  \
+        unsigned long esi,edi;                                          \
+        asm volatile("pushfl\n\t"                                       \
+                     "pushl %%ebp\n\t"                                  \
+                     "movl %%esp,%0\n\t"        /* save ESP */          \
+                     "movl %5,%%esp\n\t"        /* restore ESP */       \
+                     "movl $1f,%1\n\t"          /* save EIP */          \
+                     "pushl %6\n\t"             /* restore EIP */       \
+                     "jmp __switch_to\n"                                \
+                     "1:\t"                                             \
+                     "popl %%ebp\n\t"                                   \
+                     "popfl"                                            \
+                     :"=m" (prev->thread.esp),"=m" (prev->thread.eip),  \
+                      "=a" (last),"=S" (esi),"=D" (edi)                 \
+                     :"m" (next->thread.esp),"m" (next->thread.eip),    \
+                      "2" (prev), "d" (next));                          \
+} while (0)
+
+#define _set_base(addr,base) do { unsigned long __pr; \
+__asm__ __volatile__ ("movw %%dx,%1\n\t" \
+        "rorl $16,%%edx\n\t" \
+        "movb %%dl,%2\n\t" \
+        "movb %%dh,%3" \
+        :"=&d" (__pr) \
+        :"m" (*((addr)+2)), \
+         "m" (*((addr)+4)), \
+         "m" (*((addr)+7)), \
+         "0" (base) \
+        ); } while(0)
+
+#define _set_limit(addr,limit) do { unsigned long __lr; \
+__asm__ __volatile__ ("movw %%dx,%1\n\t" \
+        "rorl $16,%%edx\n\t" \
+        "movb %2,%%dh\n\t" \
+        "andb $0xf0,%%dh\n\t" \
+        "orb %%dh,%%dl\n\t" \
+        "movb %%dl,%2" \
+        :"=&d" (__lr) \
+        :"m" (*(addr)), \
+         "m" (*((addr)+6)), \
+         "0" (limit) \
+        ); } while(0)
+
+#define set_base(ldt,base) _set_base( ((char *)&(ldt)) , (base) )
+#define set_limit(ldt,limit) _set_limit( ((char *)&(ldt)) , ((limit)-1)>>12 )
+
+static inline unsigned long _get_base(char * addr)
+{
+        unsigned long __base;
+        __asm__("movb %3,%%dh\n\t"
+                "movb %2,%%dl\n\t"
+                "shll $16,%%edx\n\t"
+                "movw %1,%%dx"
+                :"=&d" (__base)
+                :"m" (*((addr)+2)),
+                 "m" (*((addr)+4)),
+                 "m" (*((addr)+7)));
+        return __base;
+}
+
+#define get_base(ldt) _get_base( ((char *)&(ldt)) )
+
+/*
+ * Load a segment. Fall back on loading the zero
+ * segment if something goes wrong..
+ */
+#define loadsegment(seg,value)                  \
+        asm volatile("\n"                       \
+                "1:\t"                          \
+                "movl %0,%%" #seg "\n"          \
+                "2:\n"                          \
+                ".section .fixup,\"ax\"\n"      \
+                "3:\t"                          \
+                "pushl $0\n\t"                  \
+                "popl %%" #seg "\n\t"           \
+                "jmp 2b\n"                      \
+                ".previous\n"                   \
+                ".section __ex_table,\"a\"\n\t" \
+                ".align 4\n\t"                  \
+                ".long 1b,3b\n"                 \
+                ".previous"                     \
+                : :"m" (*(unsigned int *)&(value)))
+
+/*
+ * Save a segment register away
+ */
+#define savesegment(seg, value) \
+        asm volatile("movl %%" #seg ",%0":"=m" (*(int *)&(value)))
+
+/*
+ * Clear and set 'TS' bit respectively
+ */
+#define clts() __asm__ __volatile__ ("clts")
+#define read_cr0() ({ \
+        unsigned int __dummy; \
+        __asm__( \
+                "movl %%cr0,%0\n\t" \
+                :"=r" (__dummy)); \
+        __dummy; \
+})
+#define write_cr0(x) \
+        __asm__("movl %0,%%cr0": :"r" (x));
+
+#define read_cr4() ({ \
+        unsigned int __dummy; \
+        __asm__( \
+                "movl %%cr4,%0\n\t" \
+                :"=r" (__dummy)); \
+        __dummy; \
+})
+#define write_cr4(x) \
+        __asm__("movl %0,%%cr4": :"r" (x));
+#define stts() write_cr0(8 | read_cr0())
+
+#endif  /* __KERNEL__ */
+
+#define wbinvd() \
+        __asm__ __volatile__ ("wbinvd": : :"memory");
+
+static inline unsigned long get_limit(unsigned long segment)
+{
+        unsigned long __limit;
+        __asm__("lsll %1,%0"
+                :"=r" (__limit):"r" (segment));
+        return __limit+1;
+}
+
+#define nop() __asm__ __volatile__ ("nop")
+
+#define xchg(ptr,v) ((__typeof__(*(ptr)))__xchg((unsigned long)(v),(ptr),sizeof(*(ptr))))
+
+#define tas(ptr) (xchg((ptr),1))
+
+struct __xchg_dummy { unsigned long a[100]; };
+#define __xg(x) ((struct __xchg_dummy *)(x))
+
+
+/*
+ * The semantics of XCHGCMP8B are a bit strange, this is why
+ * there is a loop and the loading of %%eax and %%edx has to
+ * be inside. This inlines well in most cases, the cached
+ * cost is around ~38 cycles. (in the future we might want
+ * to do an SIMD/3DNOW!/MMX/FPU 64-bit store here, but that
+ * might have an implicit FPU-save as a cost, so it's not
+ * clear which path to go.)
+ *
+ * cmpxchg8b must be used with the lock prefix here to allow
+ * the instruction to be executed atomically, see page 3-102
+ * of the instruction set reference 24319102.pdf. We need
+ * the reader side to see the coherent 64bit value.
+ */
+static inline void __set_64bit (unsigned long long * ptr,
+                unsigned int low, unsigned int high)
+{
+        __asm__ __volatile__ (
+                "\n1:\t"
+                "movl (%0), %%eax\n\t"
+                "movl 4(%0), %%edx\n\t"
+                "lock cmpxchg8b (%0)\n\t"
+                "jnz 1b"
+                : /* no outputs */
+                :       "D"(ptr),
+                        "b"(low),
+                        "c"(high)
+                :       "ax","dx","memory");
+}
+
+static inline void __set_64bit_constant (unsigned long long *ptr,
+                                                 unsigned long long value)
+{
+        __set_64bit(ptr,(unsigned int)(value), (unsigned int)((value)>>32ULL));
+}
+#define ll_low(x)       *(((unsigned int*)&(x))+0)
+#define ll_high(x)      *(((unsigned int*)&(x))+1)
+
+static inline void __set_64bit_var (unsigned long long *ptr,
+                         unsigned long long value)
+{
+        __set_64bit(ptr,ll_low(value), ll_high(value));
+}
+
+#define set_64bit(ptr,value) \
+(__builtin_constant_p(value) ? \
+ __set_64bit_constant(ptr, value) : \
+ __set_64bit_var(ptr, value) )
+
+#define _set_64bit(ptr,value) \
+(__builtin_constant_p(value) ? \
+ __set_64bit(ptr, (unsigned int)(value), (unsigned int)((value)>>32ULL) ) : \
+ __set_64bit(ptr, ll_low(value), ll_high(value)) )
+
+/*
+ * Note: no "lock" prefix even on SMP: xchg always implies lock anyway
+ * Note 2: xchg has side effect, so that attribute volatile is necessary,
+ *        but generally the primitive is invalid, *ptr is output argument. --ANK
+ */
+static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size)
+{
+        switch (size) {
+                case 1:
+                        __asm__ __volatile__("xchgb %b0,%1"
+                                :"=q" (x)
+                                :"m" (*__xg(ptr)), "0" (x)
+                                :"memory");
+                        break;
+                case 2:
+                        __asm__ __volatile__("xchgw %w0,%1"
+                                :"=r" (x)
+                                :"m" (*__xg(ptr)), "0" (x)
+                                :"memory");
+                        break;
+                case 4:
+                        __asm__ __volatile__("xchgl %0,%1"
+                                :"=r" (x)
+                                :"m" (*__xg(ptr)), "0" (x)
+                                :"memory");
+                        break;
+        }
+        return x;
+}
+
+/*
+ * Atomic compare and exchange.  Compare OLD with MEM, if identical,
+ * store NEW in MEM.  Return the initial value in MEM.  Success is
+ * indicated by comparing RETURN with OLD.
+ */
+
+#ifdef CONFIG_X86_CMPXCHG
+#define __HAVE_ARCH_CMPXCHG 1
+#endif
+
+static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
+                                      unsigned long new, int size)
+{
+        unsigned long prev;
+        switch (size) {
+        case 1:
+                __asm__ __volatile__(LOCK_PREFIX "cmpxchgb %b1,%2"
+                                     : "=a"(prev)
+                                     : "q"(new), "m"(*__xg(ptr)), "0"(old)
+                                     : "memory");
+                return prev;
+        case 2:
+                __asm__ __volatile__(LOCK_PREFIX "cmpxchgw %w1,%2"
+                                     : "=a"(prev)
+                                     : "q"(new), "m"(*__xg(ptr)), "0"(old)
+                                     : "memory");
+                return prev;
+        case 4:
+                __asm__ __volatile__(LOCK_PREFIX "cmpxchgl %1,%2"
+                                     : "=a"(prev)
+                                     : "q"(new), "m"(*__xg(ptr)), "0"(old)
+                                     : "memory");
+                return prev;
+        }
+        return old;
+}
+
+#define cmpxchg(ptr,o,n)\
+        ((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\
+                                        (unsigned long)(n),sizeof(*(ptr))))
+    
+#ifdef __KERNEL__
+struct alt_instr { 
+        __u8 *instr;            /* original instruction */
+        __u8 *replacement;
+        __u8  cpuid;            /* cpuid bit set for replacement */
+        __u8  instrlen;         /* length of original instruction */
+        __u8  replacementlen;   /* length of new instruction, <= instrlen */ 
+        __u8  pad;
+}; 
+#endif
+
+/* 
+ * Alternative instructions for different CPU types or capabilities.
+ * 
+ * This allows to use optimized instructions even on generic binary
+ * kernels.
+ * 
+ * length of oldinstr must be longer or equal the length of newinstr
+ * It can be padded with nops as needed.
+ * 
+ * For non barrier like inlines please define new variants
+ * without volatile and memory clobber.
+ */
+#define alternative(oldinstr, newinstr, feature)        \
+        asm volatile ("661:\n\t" oldinstr "\n662:\n"                 \
+                      ".section .altinstructions,\"a\"\n"            \
+                      "  .align 4\n"                                   \
+                      "  .long 661b\n"            /* label */          \
+                      "  .long 663f\n"            /* new instruction */         \
+                      "  .byte %c0\n"             /* feature bit */    \
+                      "  .byte 662b-661b\n"       /* sourcelen */      \
+                      "  .byte 664f-663f\n"       /* replacementlen */ \
+                      ".previous\n"                                             \
+                      ".section .altinstr_replacement,\"ax\"\n"                 \
+                      "663:\n\t" newinstr "\n664:\n"   /* replacement */    \
+                      ".previous" :: "i" (feature) : "memory")  
+
+/*
+ * Alternative inline assembly with input.
+ * 
+ * Pecularities:
+ * No memory clobber here. 
+ * Argument numbers start with 1.
+ * Best is to use constraints that are fixed size (like (%1) ... "r")
+ * If you use variable sized constraints like "m" or "g" in the 
+ * replacement maake sure to pad to the worst case length.
+ */
+#define alternative_input(oldinstr, newinstr, feature, input...)                \
+        asm volatile ("661:\n\t" oldinstr "\n662:\n"                            \
+                      ".section .altinstructions,\"a\"\n"                       \
+                      "  .align 4\n"                                            \
+                      "  .long 661b\n"            /* label */                   \
+                      "  .long 663f\n"            /* new instruction */         \
+                      "  .byte %c0\n"             /* feature bit */             \
+                      "  .byte 662b-661b\n"       /* sourcelen */               \
+                      "  .byte 664f-663f\n"       /* replacementlen */          \
+                      ".previous\n"                                             \
+                      ".section .altinstr_replacement,\"ax\"\n"                 \
+                      "663:\n\t" newinstr "\n664:\n"   /* replacement */        \
+                      ".previous" :: "i" (feature), ##input)
+
+/*
+ * Force strict CPU ordering.
+ * And yes, this is required on UP too when we're talking
+ * to devices.
+ *
+ * For now, "wmb()" doesn't actually do anything, as all
+ * Intel CPU's follow what Intel calls a *Processor Order*,
+ * in which all writes are seen in the program order even
+ * outside the CPU.
+ *
+ * I expect future Intel CPU's to have a weaker ordering,
+ * but I'd also expect them to finally get their act together
+ * and add some real memory barriers if so.
+ *
+ * Some non intel clones support out of order store. wmb() ceases to be a
+ * nop for these.
+ */
+ 
+
+/* 
+ * Actually only lfence would be needed for mb() because all stores done 
+ * by the kernel should be already ordered. But keep a full barrier for now. 
+ */
+
+#define mb() alternative("lock; addl $0,0(%%esp)", "mfence", X86_FEATURE_XMM2)
+#define rmb() alternative("lock; addl $0,0(%%esp)", "lfence", X86_FEATURE_XMM2)
+
+/**
+ * read_barrier_depends - Flush all pending reads that subsequents reads
+ * depend on.
+ *
+ * No data-dependent reads from memory-like regions are ever reordered
+ * over this barrier.  All reads preceding this primitive are guaranteed
+ * to access memory (but not necessarily other CPUs' caches) before any
+ * reads following this primitive that depend on the data return by
+ * any of the preceding reads.  This primitive is much lighter weight than
+ * rmb() on most CPUs, and is never heavier weight than is
+ * rmb().
+ *
+ * These ordering constraints are respected by both the local CPU
+ * and the compiler.
+ *
+ * Ordering is not guaranteed by anything other than these primitives,
+ * not even by data dependencies.  See the documentation for
+ * memory_barrier() for examples and URLs to more information.
+ *
+ * For example, the following code would force ordering (the initial
+ * value of "a" is zero, "b" is one, and "p" is "&a"):
+ *
+ * <programlisting>
+ *      CPU 0                           CPU 1
+ *
+ *      b = 2;
+ *      memory_barrier();
+ *      p = &b;                         q = p;
+ *                                      read_barrier_depends();
+ *                                      d = *q;
+ * </programlisting>
+ *
+ * because the read of "*q" depends on the read of "p" and these
+ * two reads are separated by a read_barrier_depends().  However,
+ * the following code, with the same initial values for "a" and "b":
+ *
+ * <programlisting>
+ *      CPU 0                           CPU 1
+ *
+ *      a = 2;
+ *      memory_barrier();
+ *      b = 3;                          y = b;
+ *                                      read_barrier_depends();
+ *                                      x = a;
+ * </programlisting>
+ *
+ * does not enforce ordering, since there is no data dependency between
+ * the read of "a" and the read of "b".  Therefore, on some CPUs, such
+ * as Alpha, "y" could be set to 3 and "x" to 0.  Use rmb()
+ * in cases like thiswhere there are no data dependencies.
+ **/
+
+#define read_barrier_depends()  do { } while(0)
+
+#ifdef CONFIG_X86_OOSTORE
+/* Actually there are no OOO store capable CPUs for now that do SSE, 
+   but make it already an possibility. */
+#define wmb() alternative("lock; addl $0,0(%%esp)", "sfence", X86_FEATURE_XMM)
+#else
+#define wmb()   __asm__ __volatile__ ("": : :"memory")
+#endif
+
+#ifdef CONFIG_SMP
+#define smp_mb()        mb()
+#define smp_rmb()       rmb()
+#define smp_wmb()       wmb()
+#define smp_read_barrier_depends()      read_barrier_depends()
+#define set_mb(var, value) do { xchg(&var, value); } while (0)
+#else
+#define smp_mb()        barrier()
+#define smp_rmb()       barrier()
+#define smp_wmb()       barrier()
+#define smp_read_barrier_depends()      do { } while(0)
+#define set_mb(var, value) do { var = value; barrier(); } while (0)
+#endif
+
+#define set_wmb(var, value) do { var = value; wmb(); } while (0)
+
+/* interrupt control.. */
+#define local_save_flags(x)     do { typecheck(unsigned long,x); __asm__ __volatile__("pushfl ; popl %0":"=g" (x): /* no input */); } while (0)
+#define local_irq_restore(x)    do { typecheck(unsigned long,x); __asm__ __volatile__("pushl %0 ; popfl": /* no output */ :"g" (x):"memory", "cc"); } while (0)
+#define local_irq_disable()     __asm__ __volatile__("cli": : :"memory")
+#define local_irq_enable()      __asm__ __volatile__("sti": : :"memory")
+/* used in the idle loop; sti takes one instruction cycle to complete */
+#define safe_halt()             __asm__ __volatile__("sti; hlt": : :"memory")
+
+#define irqs_disabled()                 \
+({                                      \
+        unsigned long flags;            \
+        local_save_flags(flags);        \
+        !(flags & (1<<9));              \
+})
+
+/* For spinlocks etc */
+#define local_irq_save(x)       __asm__ __volatile__("pushfl ; popl %0 ; cli":"=g" (x): /* no input */ :"memory")
+
+/*
+ * disable hlt during certain critical i/o operations
+ */
+#define HAVE_DISABLE_HLT
+void disable_hlt(void);
+void enable_hlt(void);
+
+extern int es7000_plat;
+void cpu_idle_wait(void);
+
+extern unsigned long arch_align_stack(unsigned long sp);
+
+#endif