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| -rw-r--r-- | bsd-core/drm_atomic.h | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/bsd-core/drm_atomic.h b/bsd-core/drm_atomic.h new file mode 100644 index 00000000..26e7d452 --- /dev/null +++ b/bsd-core/drm_atomic.h @@ -0,0 +1,141 @@ +/** + * \file drm_atomic.h + * Atomic operations used in the DRM which may or may not be provided by the OS. + * + * \author Eric Anholt <anholt@FreeBSD.org> + */ + +/* + * Copyright 2004 Eric Anholt + * All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + */ + +/* Many of these implementations are rather fake, but good enough. */ + +typedef u_int32_t atomic_t; + +#ifdef __FreeBSD__ +#define atomic_set(p, v) (*(p) = (v)) +#define atomic_read(p) (*(p)) +#define atomic_inc(p) atomic_add_int(p, 1) +#define atomic_dec(p) atomic_subtract_int(p, 1) +#define atomic_add(n, p) atomic_add_int(p, n) +#define atomic_sub(n, p) atomic_subtract_int(p, n) +#else /* __FreeBSD__ */ +/* FIXME */ +#define atomic_set(p, v) (*(p) = (v)) +#define atomic_read(p) (*(p)) +#define atomic_inc(p) (*(p) += 1) +#define atomic_dec(p) (*(p) -= 1) +#define atomic_add(n, p) (*(p) += (n)) +#define atomic_sub(n, p) (*(p) -= (n)) +/* FIXME */ +#define atomic_add_int(p, v) *(p) += v +#define atomic_subtract_int(p, v) *(p) -= v +#define atomic_set_int(p, bits) *(p) |= (bits) +#define atomic_clear_int(p, bits) *(p) &= ~(bits) +#endif /* !__FreeBSD__ */ + +#if !defined(__FreeBSD_version) || (__FreeBSD_version < 500000) +#if defined(__i386__) +/* The extra atomic functions from 5.0 haven't been merged to 4.x */ +static __inline int +atomic_cmpset_int(volatile u_int *dst, u_int exp, u_int src) +{ + int res = exp; + + __asm __volatile ( + " lock ; " + " cmpxchgl %1,%2 ; " + " setz %%al ; " + " movzbl %%al,%0 ; " + "1: " + "# atomic_cmpset_int" + : "+a" (res) /* 0 (result) */ + : "r" (src), /* 1 */ + "m" (*(dst)) /* 2 */ + : "memory"); + + return (res); +} +#else /* __i386__ */ +static __inline int +atomic_cmpset_int(__volatile__ int *dst, int old, int new) +{ + int s = splhigh(); + if (*dst==old) { + *dst = new; + splx(s); + return 1; + } + splx(s); + return 0; +} +#endif /* !__i386__ */ +#endif /* !__FreeBSD_version || __FreeBSD_version < 500000 */ + +static __inline atomic_t +test_and_set_bit(int b, volatile void *p) +{ + int s = splhigh(); + unsigned int m = 1<<b; + unsigned int r = *(volatile int *)p & m; + *(volatile int *)p |= m; + splx(s); + return r; +} + +static __inline void +clear_bit(int b, volatile void *p) +{ + atomic_clear_int(((volatile int *)p) + (b >> 5), 1 << (b & 0x1f)); +} + +static __inline void +set_bit(int b, volatile void *p) +{ + atomic_set_int(((volatile int *)p) + (b >> 5), 1 << (b & 0x1f)); +} + +static __inline int +test_bit(int b, volatile void *p) +{ + return ((volatile int *)p)[b >> 5] & (1 << (b & 0x1f)); +} + +static __inline int +find_first_zero_bit(volatile void *p, int max) +{ + int b; + volatile int *ptr = (volatile int *)p; + + for (b = 0; b < max; b += 32) { + if (ptr[b >> 5] != ~0) { + for (;;) { + if ((ptr[b >> 5] & (1 << (b & 0x1f))) == 0) + return b; + b++; + } + } + } + return max; +} |