static __inline__ int _NumCPUs( void ) { return (_cpu_capabilities & kNumCPUs) >> kNumCPUsShift; }
#endif /* __ASSEMBLER__ */
+
+
+/*
+ * The shared kernel/user "comm page(s)":
+ *
+ * The last eight pages of every address space are reserved for the kernel/user
+ * "comm area". Because they can be addressed via a sign-extended 16-bit field,
+ * it is particularly efficient to access code or data in the comm area with
+ * absolute branches (ba, bla, bca) or absolute load/stores ("lwz r0,-4096(0)").
+ * Because the comm area can be reached from anywhere, dyld is not needed.
+ * Although eight pages are reserved, presently only two are populated and mapped.
+ *
+ * Routines on the comm page(s) can be thought of as the firmware for extended processor
+ * instructions, whose opcodes are special forms of "bla". Ie, they are cpu
+ * capabilities. During system initialization, the kernel populates the comm page with
+ * code customized for the particular processor and platform.
+ *
+ * Because Mach VM cannot map the last page of an address space, the max length of
+ * the comm area is seven pages.
+ */
+
+#define _COMM_PAGE_BASE_ADDRESS (-8*4096) // start at page -8, ie 0xFFFF8000
+#define _COMM_PAGE_AREA_LENGTH ( 7*4096) // reserved length of entire comm area
+#define _COMM_PAGE_AREA_USED ( 2*4096) // we use two pages so far
+
+/* data in the comm page */
+
+#define _COMM_PAGE_SIGNATURE (_COMM_PAGE_BASE_ADDRESS+0x000) // first few bytes are a signature
+#define _COMM_PAGE_VERSION (_COMM_PAGE_BASE_ADDRESS+0x01E) // 16-bit version#
+#define _COMM_PAGE_THIS_VERSION 1 // this is version 1 of the commarea format
+
+#define _COMM_PAGE_CPU_CAPABILITIES (_COMM_PAGE_BASE_ADDRESS+0x020) // mirror of extern int _cpu_capabilities
+#define _COMM_PAGE_NCPUS (_COMM_PAGE_BASE_ADDRESS+0x021) // number of configured CPUs
+#define _COMM_PAGE_ALTIVEC (_COMM_PAGE_BASE_ADDRESS+0x024) // nonzero if Altivec available
+#define _COMM_PAGE_64_BIT (_COMM_PAGE_BASE_ADDRESS+0x025) // nonzero if 64-bit processor
+#define _COMM_PAGE_CACHE_LINESIZE (_COMM_PAGE_BASE_ADDRESS+0x026) // cache line size (16-bit field)
+
+#define _COMM_PAGE_UNUSED1 (_COMM_PAGE_BASE_ADDRESS+0x030) // 16 unused bytes
+
+#define _COMM_PAGE_2_TO_52 (_COMM_PAGE_BASE_ADDRESS+0x040) // double float constant 2**52
+#define _COMM_PAGE_10_TO_6 (_COMM_PAGE_BASE_ADDRESS+0x048) // double float constant 10**6
+
+#define _COMM_PAGE_UNUSED2 (_COMM_PAGE_BASE_ADDRESS+0x050) // 16 unused bytes
+
+#define _COMM_PAGE_TIMEBASE (_COMM_PAGE_BASE_ADDRESS+0x060) // used by gettimeofday()
+#define _COMM_PAGE_TIMESTAMP (_COMM_PAGE_BASE_ADDRESS+0x068) // used by gettimeofday()
+#define _COMM_PAGE_SEC_PER_TICK (_COMM_PAGE_BASE_ADDRESS+0x070) // used by gettimeofday()
+
+#define _COMM_PAGE_UNUSED3 (_COMM_PAGE_BASE_ADDRESS+0x080) // 384 unused bytes
+
+ /* jump table (bla to this address, which may be a branch to the actual code somewhere else) */
+ /* When new jump table entries are added, corresponding symbols should be added below */
+
+#define _COMM_PAGE_ABSOLUTE_TIME (_COMM_PAGE_BASE_ADDRESS+0x200) // mach_absolute_time()
+#define _COMM_PAGE_SPINLOCK_TRY (_COMM_PAGE_BASE_ADDRESS+0x220) // spinlock_try()
+#define _COMM_PAGE_SPINLOCK_LOCK (_COMM_PAGE_BASE_ADDRESS+0x260) // spinlock_lock()
+#define _COMM_PAGE_SPINLOCK_UNLOCK (_COMM_PAGE_BASE_ADDRESS+0x2a0) // spinlock_unlock()
+#define _COMM_PAGE_PTHREAD_GETSPECIFIC (_COMM_PAGE_BASE_ADDRESS+0x2c0) // pthread_getspecific()
+#define _COMM_PAGE_GETTIMEOFDAY (_COMM_PAGE_BASE_ADDRESS+0x2e0) // used by gettimeofday()
+#define _COMM_PAGE_FLUSH_DCACHE (_COMM_PAGE_BASE_ADDRESS+0x4e0) // sys_dcache_flush()
+#define _COMM_PAGE_FLUSH_ICACHE (_COMM_PAGE_BASE_ADDRESS+0x520) // sys_icache_invalidate()
+#define _COMM_PAGE_PTHREAD_SELF (_COMM_PAGE_BASE_ADDRESS+0x580) // pthread_self()
+#define _COMM_PAGE_UNUSED4 (_COMM_PAGE_BASE_ADDRESS+0x5a0) // 32 unused bytes
+#define _COMM_PAGE_RELINQUISH (_COMM_PAGE_BASE_ADDRESS+0x5c0) // used by spinlocks
+
+#define _COMM_PAGE_UNUSED5 (_COMM_PAGE_BASE_ADDRESS+0x5e0) // 32 unused bytes
+
+#define _COMM_PAGE_BZERO (_COMM_PAGE_BASE_ADDRESS+0x600) // bzero()
+#define _COMM_PAGE_BCOPY (_COMM_PAGE_BASE_ADDRESS+0x780) // bcopy()
+#define _COMM_PAGE_MEMCPY (_COMM_PAGE_BASE_ADDRESS+0x7a0) // memcpy()
+#define _COMM_PAGE_MEMMOVE (_COMM_PAGE_BASE_ADDRESS+0x7a0) // memmove()
+
+#define _COMM_PAGE_UNUSED6 (_COMM_PAGE_BASE_ADDRESS+0xF80) // 128 unused bytes
+
+#define _COMM_PAGE_BIGCOPY (_COMM_PAGE_BASE_ADDRESS+0x1000)// very-long-operand copies
+
+#define _COMM_PAGE_END (_COMM_PAGE_BASE_ADDRESS+0x1600)// end of common page
+
+#ifdef __ASSEMBLER__
+#ifdef __COMM_PAGE_SYMBOLS
+
+#define CREATE_COMM_PAGE_SYMBOL(symbol_name, symbol_address) \
+ .org (symbol_address - _COMM_PAGE_BASE_ADDRESS) @\
+symbol_name: nop
+
+ .text // Required to make a well behaved symbol file
+
+ CREATE_COMM_PAGE_SYMBOL(___mach_absolute_time, _COMM_PAGE_ABSOLUTE_TIME)
+ CREATE_COMM_PAGE_SYMBOL(___spin_lock_try, _COMM_PAGE_SPINLOCK_TRY)
+ CREATE_COMM_PAGE_SYMBOL(___spin_lock, _COMM_PAGE_SPINLOCK_LOCK)
+ CREATE_COMM_PAGE_SYMBOL(___spin_unlock, _COMM_PAGE_SPINLOCK_UNLOCK)
+ CREATE_COMM_PAGE_SYMBOL(___pthread_getspecific, _COMM_PAGE_PTHREAD_GETSPECIFIC)
+ CREATE_COMM_PAGE_SYMBOL(___gettimeofday, _COMM_PAGE_GETTIMEOFDAY)
+ CREATE_COMM_PAGE_SYMBOL(___sys_dcache_flush, _COMM_PAGE_FLUSH_DCACHE)
+ CREATE_COMM_PAGE_SYMBOL(___sys_icache_invalidate, _COMM_PAGE_FLUSH_ICACHE)
+ CREATE_COMM_PAGE_SYMBOL(___pthread_self, _COMM_PAGE_PTHREAD_SELF)
+ CREATE_COMM_PAGE_SYMBOL(___spin_lock_relinquish, _COMM_PAGE_RELINQUISH)
+ CREATE_COMM_PAGE_SYMBOL(___bzero, _COMM_PAGE_BZERO)
+ CREATE_COMM_PAGE_SYMBOL(___bcopy, _COMM_PAGE_BCOPY)
+ CREATE_COMM_PAGE_SYMBOL(___memcpy, _COMM_PAGE_MEMCPY)
+// CREATE_COMM_PAGE_SYMBOL(___memmove, _COMM_PAGE_MEMMOVE)
+ CREATE_COMM_PAGE_SYMBOL(___bigcopy, _COMM_PAGE_BIGCOPY)
+ CREATE_COMM_PAGE_SYMBOL(___end_comm_page, _COMM_PAGE_END)
+
+ .data // Required to make a well behaved symbol file
+ .long 0 // Required to make a well behaved symbol file
+
+#endif /* __COMM_PAGE_SYMBOLS */
+#endif /* __ASSEMBLER__ */
+
#endif /* __APPLE_API_PRIVATE */
#endif /* _PPC_CPU_CAPABILITIES_H */
projects / apple / xnu.git / blobdiff