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1 /*

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 * @OSF_COPYRIGHT@

30 *

31 */

33 #ifndef ARM_CPU_DATA

34 #define ARM_CPU_DATA

36 #ifdef MACH_KERNEL_PRIVATE

38 #include <mach_assert.h>

39 #include <kern/assert.h>

40 #include <kern/kern_types.h>

41 #include <kern/processor.h>

42 #include <pexpert/pexpert.h>

43 #include <arm/thread.h>

44 #include <arm/proc_reg.h>

46 #include <mach/mach_types.h>

47 #include <machine/thread.h>

49 #define current_thread() current_thread_fast()

 static inline __attribute__((const)) thread_t

52 current_thread_fast(void)

53 {

54 #if defined(__arm64__)

         return (thread_t)(__builtin_arm_rsr64("TPIDR_EL1"));

56 #else

         return (thread_t)(__builtin_arm_mrc(15, 0, 13, 0, 4));  // TPIDRPRW

58 #endif

59 }

61 /*

62 * The "volatile" flavor of current_thread() is intended for use by

63 * scheduler code which may need to update the thread pointer in the

64 * course of a context switch. Any call to current_thread() made

65 * prior to the thread pointer update should be safe to optimize away

66 * as it should be consistent with that thread's state to the extent

67 * the compiler can reason about it. Likewise, the context switch

68 * path will eventually result in an arbitrary branch to the new

69 * thread's pc, about which the compiler won't be able to reason.

70 * Thus any compile-time optimization of current_thread() calls made

71 * within the new thread should be safely encapsulated in its

72 * register/stack state. The volatile form therefore exists to cover

73 * the window between the thread pointer update and the branch to

74 * the new pc.

75 */

76 static inline thread_t

77 current_thread_volatile(void)

78 {

79 /* The compiler treats rsr64 as const, which can allow

80 * it to eliminate redundant calls, which we don't want here.

81 * Thus we use volatile asm. The mrc used for arm32 should be

82 * treated as volatile however. */

83 #if defined(__arm64__)

84 thread_t result;

         __asm__ volatile ("mrs %0, TPIDR_EL1" : "=r" (result));

86 return result;

87 #else

         return (thread_t)(__builtin_arm_mrc(15, 0, 13, 0, 4));  // TPIDRPRW

89 #endif

90 }

92 #if defined(__arm64__)

94 static inline vm_offset_t

95 exception_stack_pointer(void)

96 {

97 vm_offset_t result = 0;

98 __asm__ volatile (

99 "msr SPSel, #1 \n"

                  "mov           %0, sp     \n"

101 "msr SPSel, #0 \n"

102 : "=r" (result));

103

104 return result;

105 }

106

107 #endif /* defined(__arm64__) */

108

109 #define getCpuDatap() current_thread()->machine.CpuDatap

110 #define current_cpu_datap() getCpuDatap()

111

 extern int                       get_preemption_level(void);

113

114 #define mp_disable_preemption() _disable_preemption()

115 #define mp_enable_preemption() _enable_preemption()

116

117 #endif /* MACH_KERNEL_PRIVATE */

118

119 #endif /* ARM_CPU_DATA */