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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/gpu/drm/lib
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpu/drm/lib')
-rw-r--r--drivers/gpu/drm/lib/drm_random.c43
-rw-r--r--drivers/gpu/drm/lib/drm_random.h28
2 files changed, 71 insertions, 0 deletions
diff --git a/drivers/gpu/drm/lib/drm_random.c b/drivers/gpu/drm/lib/drm_random.c
new file mode 100644
index 000000000..31b5a3e21
--- /dev/null
+++ b/drivers/gpu/drm/lib/drm_random.c
@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bitops.h>
+#include <linux/kernel.h>
+#include <linux/random.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#include "drm_random.h"
+
+u32 drm_prandom_u32_max_state(u32 ep_ro, struct rnd_state *state)
+{
+ return upper_32_bits((u64)prandom_u32_state(state) * ep_ro);
+}
+EXPORT_SYMBOL(drm_prandom_u32_max_state);
+
+void drm_random_reorder(unsigned int *order, unsigned int count,
+ struct rnd_state *state)
+{
+ unsigned int i, j;
+
+ for (i = 0; i < count; ++i) {
+ BUILD_BUG_ON(sizeof(unsigned int) > sizeof(u32));
+ j = drm_prandom_u32_max_state(count, state);
+ swap(order[i], order[j]);
+ }
+}
+EXPORT_SYMBOL(drm_random_reorder);
+
+unsigned int *drm_random_order(unsigned int count, struct rnd_state *state)
+{
+ unsigned int *order, i;
+
+ order = kmalloc_array(count, sizeof(*order), GFP_KERNEL);
+ if (!order)
+ return order;
+
+ for (i = 0; i < count; i++)
+ order[i] = i;
+
+ drm_random_reorder(order, count, state);
+ return order;
+}
+EXPORT_SYMBOL(drm_random_order);
diff --git a/drivers/gpu/drm/lib/drm_random.h b/drivers/gpu/drm/lib/drm_random.h
new file mode 100644
index 000000000..5543bf047
--- /dev/null
+++ b/drivers/gpu/drm/lib/drm_random.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __DRM_RANDOM_H__
+#define __DRM_RANDOM_H__
+
+/* This is a temporary home for a couple of utility functions that should
+ * be transposed to lib/ at the earliest convenience.
+ */
+
+#include <linux/random.h>
+
+#define DRM_RND_STATE_INITIALIZER(seed__) ({ \
+ struct rnd_state state__; \
+ prandom_seed_state(&state__, (seed__)); \
+ state__; \
+})
+
+#define DRM_RND_STATE(name__, seed__) \
+ struct rnd_state name__ = DRM_RND_STATE_INITIALIZER(seed__)
+
+unsigned int *drm_random_order(unsigned int count,
+ struct rnd_state *state);
+void drm_random_reorder(unsigned int *order,
+ unsigned int count,
+ struct rnd_state *state);
+u32 drm_prandom_u32_max_state(u32 ep_ro,
+ struct rnd_state *state);
+
+#endif /* !__DRM_RANDOM_H__ */