1 files changed, 143 insertions, 0 deletions
diff --git a/sys/dev/drm/drm_atomic.h b/sys/dev/drm/drm_atomic.h
new file mode 100644
index 0000000..8cdabc7
--- /dev/null
+++ b/sys/dev/drm/drm_atomic.h
@@ -0,0 +1,143 @@
+/**
+ * \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.
+ *
+ * $FreeBSD$
+ */
+
+/* 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;
+}