| 1 |
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| 2 | |
| 3 | * Copyright (C) 2017 Linaro Ltd. <[email protected]>
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| 4 |
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| 5 |
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| 6 | #ifndef __ASM_SIMD_H
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| 7 | #define __ASM_SIMD_H
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| 8 |
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| 9 | #include <linux/cleanup.h>
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| 10 | #include <linux/compiler.h>
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| 11 | #include <linux/irqflags.h>
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| 12 | #include <linux/percpu.h>
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| 13 | #include <linux/preempt.h>
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| 14 | #include <linux/types.h>
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| 15 |
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| 16 | #include <asm/neon.h>
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| 17 |
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| 18 | #ifdef CONFIG_KERNEL_MODE_NEON
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| 19 |
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| 20 | |
| 21 | * may_use_simd - whether it is allowable at this time to issue SIMD
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| 22 | * instructions or access the SIMD register file
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| 23 | *
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| 24 | * Callers must not assume that the result remains true beyond the next
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| 25 | * preempt_enable() or return from softirq context.
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| 26 |
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| 27 | static __must_check inline bool may_use_simd(void)
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| 28 | {
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| 29 | |
| 30 | * We must make sure that the SVE has been initialized properly
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| 31 | * before using the SIMD in kernel.
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| 32 |
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| 33 | return !WARN_ON(!system_capabilities_finalized()) &&
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| 34 | system_supports_fpsimd() &&
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| 35 | !in_hardirq() && !in_nmi();
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| 36 | }
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| 37 |
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| 38 | #else
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| 39 |
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| 40 | static __must_check inline bool may_use_simd(void) {
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| 41 | return false;
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| 42 | }
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| 43 |
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| 44 | #endif
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| 45 |
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| 46 | DEFINE_LOCK_GUARD_1(ksimd,
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| 47 | struct user_fpsimd_state,
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| 48 | kernel_neon_begin(_T->lock),
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| 49 | kernel_neon_end(_T->lock))
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| 50 |
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| 51 | #define __scoped_ksimd(_label) \
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| 52 | for (struct user_fpsimd_state __uninitialized __st; \
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| 53 | true; ({ goto _label; })) \
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| 54 | if (0) { \
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| 55 | _label: break; \
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| 56 | } else scoped_guard(ksimd, &__st)
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| 57 |
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| 58 | #define scoped_ksimd() __scoped_ksimd(__UNIQUE_ID(label))
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| 59 |
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| 60 | #endif
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