kern: Introduce clock device framework

This commit introduces a new framework we call "clkdev". It is used to
keep track of the clock sources on the system and be able to fetch them
later based on specific attributes.

Signed-off-by: Ian Moffett <ian@osmora.org>

1 files changed, 76 insertions, 0 deletions

diff --git a/src/sys/include/os/clkdev.h b/src/sys/include/os/clkdev.h
new file mode 100644
index 0000000..1f776cd
--- /dev/null
+++ b/src/sys/include/os/clkdev.h
@@ -0,0 +1,76 @@
+/*
+ * Copyright (c) 2025 Ian Marco Moffett and L5 engineers
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the project nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _OS_CLKDEV_H_
+#define _OS_CLKDEV_H_ 1
+
+#include <sys/types.h>
+#include <sys/param.h>
+
+/* Clock attributes */
+#define CLKDEV_MSLEEP BIT(0)    /* Has msleep() */
+
+#define MAX_CLKDEV 4
+
+/*
+ * Represents a clock device for time
+ * keeping
+ *
+ * @name: Name of clock
+ * @msleep: Sleep for 'n' msec
+ * @attr: Attribute mask
+ */
+struct clkdev {
+    const char *name;
+    int(*msleep)(size_t ms);
+    uint16_t attr;
+};
+
+/*
+ * Registers a clock device
+ *
+ * @clkdev: Descriptor of clock device to use
+ *
+ * Returns zero on success, otherwise a less than
+ * zero value.
+ */
+int clkdev_register(struct clkdev *clkdev);
+
+/*
+ * Get a specific clock device by index
+ *
+ * @attr: Attribute mask for clock to include
+ * @clkdev_res: Clock device pointer result written here
+ *
+ * Returns zero on success, otherwise a less than zero
+ * value.
+ */
+int clkdev_get(uint16_t attr, struct clkdev **clkdev_res);
+
+#endif  /* !_OS_CLKDEV_H_ */