gen/platfunc.h

   1 /*
   2  * Copyright (c) 2003-2010 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28
  29 #if defined(__i386__) || defined(__x86_64__)
  30
  31 #ifndef _I386_PLATFUNC_H
  32 #define _I386_PLATFUNC_H
  33
  34 #ifndef __ASSEMBLER__
  35 #include <stdint.h>
  36 #endif /* __ASSEMBLER__ */
  37
  38 // This is a shared macro which calls PLATFUNC_VARIANT_NAME which has different
  39 // implementations in __ASSEMBLER__ and !__ASSEMBLER__
  40 #define PLATFUNC_DESCRIPTOR_NAME(name, variant) \
  41         PLATFUNC_VARIANT_NAME(platfunc_ ## name, variant)
  42
  43 #ifdef  __ASSEMBLER__
  44
  45 /* When trying to acquire a spinlock or mutex, we will spin in
  46  * user mode for awhile, before entering the kernel to relinquish.
  47  * MP_SPIN_TRIES is the initial value of _COMM_PAGE_SPIN_COUNT.
  48  * The idea is that _COMM_PAGE_SPIN_COUNT will be adjusted up or
  49  * down as the machine is plugged in/out, etc.
  50  * At present spinlocks do not use _COMM_PAGE_SPIN_COUNT.
  51  * They use MP_SPIN_TRIES directly.
  52  */
  53 #define MP_SPIN_TRIES   1000
  54
  55 #define PLATFUNC_VARIANT_NAME(name, variant) _ ## name ## $VARIANT$ ## variant
  56
  57 #if defined (__i386__)
  58 #define PLATFUNC_DESCRIPTOR_FIELD_POINTER .long
  59 #define PLATFUNC_DESCRIPTOR_REFERENCE(name, variant) \
  60         .long PLATFUNC_DESCRIPTOR_NAME(name, variant)
  61 #elif defined (__x86_64__)
  62 #define PLATFUNC_DESCRIPTOR_FIELD_POINTER .quad
  63 #define PLATFUNC_DESCRIPTOR_REFERENCE(name, variant) \
  64         .quad PLATFUNC_DESCRIPTOR_NAME(name, variant)
  65 #else
  66 #error unsupported architecture
  67 #endif
  68
  69 #ifdef VARIANT_DYLD
  70
  71 #define PLATFUNC_FUNCTION_START_GENERIC(name, variant, codetype, alignment) \
  72         PLATFUNC_FUNCTION_START(name, variant, codetype, alignment) \
  73         .globl _ ## name ;\
  74         _ ## name ## :
  75
  76 #define PLATFUNC_DESCRIPTOR(name, variant, must, cant)
  77
  78 #else /* VARIANT_DYLD */
  79
  80 #define PLATFUNC_FUNCTION_START_GENERIC PLATFUNC_FUNCTION_START
  81
  82 #define PLATFUNC_DESCRIPTOR(name, variant, must, cant) \
  83         .const_data ;\
  84         .private_extern PLATFUNC_DESCRIPTOR_NAME(name, variant) ;\
  85         PLATFUNC_DESCRIPTOR_NAME(name, variant) ## : ;\
  86         PLATFUNC_DESCRIPTOR_FIELD_POINTER PLATFUNC_VARIANT_NAME(name, variant) ;\
  87         .long must ;\
  88         .long cant ;\
  89         .text
  90
  91 #endif /* VARIANT_DYLD */
  92
  93 #define PLATFUNC_FUNCTION_START(name, variant, codetype, alignment) \
  94         .text ;\
  95         .align alignment, 0x90 ;\
  96         .private_extern PLATFUNC_VARIANT_NAME(name, variant) ;\
  97         PLATFUNC_VARIANT_NAME(name, variant) ## :
  98
  99 #else /* __ASSEMBLER__ */
 100
 101 #define PLATFUNC_VARIANT_NAME(name, variant) name ## $VARIANT$ ## variant
 102 #define PLATFUNC_DESCRIPTOR_PROTOTYPE(name, variant) extern const platfunc_descriptor PLATFUNC_DESCRIPTOR_NAME(name, variant);
 103 #define PLATFUNC_DESCRIPTOR_REFERENCE(name, variant) &PLATFUNC_DESCRIPTOR_NAME(name, variant)
 104
 105 #define PLATFUNC_DESCRIPTOR(name, variant, must, cant) \
 106         extern void PLATFUNC_VARIANT_NAME(name, variant) (void); \
 107         const platfunc_descriptor PLATFUNC_DESCRIPTOR_NAME(name, variant) = { \
 108                 .address = PLATFUNC_VARIANT_NAME(name, variant), \
 109                 .musthave = must, \
 110                 .canthave = cant \
 111         }
 112
 113 /*
 114  * Each potential platfunc routine is described by one of these.
 115  * Note that the PLATFUNC_DESCRIPTOR macro (above), used in
 116  * assembly language, must agree with this.
 117  */
 118
 119 typedef struct  platfunc_descriptor     {
 120         void       *address; // address of code
 121         uint32_t   musthave; // _cpu_capability bits we must have
 122         uint32_t   canthave; // _cpu_capability bits we can't have
 123 } platfunc_descriptor;
 124
 125 void *find_platform_function(const platfunc_descriptor *descriptors[]);
 126
 127 #endif  /* __ASSEMBLER__ */
 128
 129 #endif /* _I386_PLATFUNC_H */
 130
 131 #endif /* __i386__ || __x86_64__ */