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-rw-r--r--hw/core/qdev-clock.c168
1 files changed, 168 insertions, 0 deletions
diff --git a/hw/core/qdev-clock.c b/hw/core/qdev-clock.c
new file mode 100644
index 0000000000..62035aef83
--- /dev/null
+++ b/hw/core/qdev-clock.c
@@ -0,0 +1,168 @@
+/*
+ * Device's clock input and output
+ *
+ * Copyright GreenSocs 2016-2020
+ *
+ * Authors:
+ *  Frederic Konrad
+ *  Damien Hedde
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "hw/qdev-clock.h"
+#include "hw/qdev-core.h"
+#include "qapi/error.h"
+
+/*
+ * qdev_init_clocklist:
+ * Add a new clock in a device
+ */
+static NamedClockList *qdev_init_clocklist(DeviceState *dev, const char *name,
+                                           bool output, Clock *clk)
+{
+    NamedClockList *ncl;
+
+    /*
+     * Clock must be added before realize() so that we can compute the
+     * clock's canonical path during device_realize().
+     */
+    assert(!dev->realized);
+
+    /*
+     * The ncl structure is freed by qdev_finalize_clocklist() which will
+     * be called during @dev's device_finalize().
+     */
+    ncl = g_new0(NamedClockList, 1);
+    ncl->name = g_strdup(name);
+    ncl->output = output;
+    ncl->alias = (clk != NULL);
+
+    /*
+     * Trying to create a clock whose name clashes with some other
+     * clock or property is a bug in the caller and we will abort().
+     */
+    if (clk == NULL) {
+        clk = CLOCK(object_new(TYPE_CLOCK));
+        object_property_add_child(OBJECT(dev), name, OBJECT(clk), &error_abort);
+        if (output) {
+            /*
+             * Remove object_new()'s initial reference.
+             * Note that for inputs, the reference created by object_new()
+             * will be deleted in qdev_finalize_clocklist().
+             */
+            object_unref(OBJECT(clk));
+        }
+    } else {
+        object_property_add_link(OBJECT(dev), name,
+                                 object_get_typename(OBJECT(clk)),
+                                 (Object **) &ncl->clock,
+                                 NULL, OBJ_PROP_LINK_STRONG, &error_abort);
+    }
+
+    ncl->clock = clk;
+
+    QLIST_INSERT_HEAD(&dev->clocks, ncl, node);
+    return ncl;
+}
+
+void qdev_finalize_clocklist(DeviceState *dev)
+{
+    /* called by @dev's device_finalize() */
+    NamedClockList *ncl, *ncl_next;
+
+    QLIST_FOREACH_SAFE(ncl, &dev->clocks, node, ncl_next) {
+        QLIST_REMOVE(ncl, node);
+        if (!ncl->output && !ncl->alias) {
+            /*
+             * We kept a reference on the input clock to ensure it lives up to
+             * this point so we can safely remove the callback.
+             * It avoids having a callback to a deleted object if ncl->clock
+             * is still referenced somewhere else (eg: by a clock output).
+             */
+            clock_clear_callback(ncl->clock);
+            object_unref(OBJECT(ncl->clock));
+        }
+        g_free(ncl->name);
+        g_free(ncl);
+    }
+}
+
+Clock *qdev_init_clock_out(DeviceState *dev, const char *name)
+{
+    NamedClockList *ncl;
+
+    assert(name);
+
+    ncl = qdev_init_clocklist(dev, name, true, NULL);
+
+    return ncl->clock;
+}
+
+Clock *qdev_init_clock_in(DeviceState *dev, const char *name,
+                            ClockCallback *callback, void *opaque)
+{
+    NamedClockList *ncl;
+
+    assert(name);
+
+    ncl = qdev_init_clocklist(dev, name, false, NULL);
+
+    if (callback) {
+        clock_set_callback(ncl->clock, callback, opaque);
+    }
+    return ncl->clock;
+}
+
+static NamedClockList *qdev_get_clocklist(DeviceState *dev, const char *name)
+{
+    NamedClockList *ncl;
+
+    QLIST_FOREACH(ncl, &dev->clocks, node) {
+        if (strcmp(name, ncl->name) == 0) {
+            return ncl;
+        }
+    }
+
+    return NULL;
+}
+
+Clock *qdev_get_clock_in(DeviceState *dev, const char *name)
+{
+    NamedClockList *ncl;
+
+    assert(name);
+
+    ncl = qdev_get_clocklist(dev, name);
+    assert(!ncl->output);
+
+    return ncl->clock;
+}
+
+Clock *qdev_get_clock_out(DeviceState *dev, const char *name)
+{
+    NamedClockList *ncl;
+
+    assert(name);
+
+    ncl = qdev_get_clocklist(dev, name);
+    assert(ncl->output);
+
+    return ncl->clock;
+}
+
+Clock *qdev_alias_clock(DeviceState *dev, const char *name,
+                        DeviceState *alias_dev, const char *alias_name)
+{
+    NamedClockList *ncl;
+
+    assert(name && alias_name);
+
+    ncl = qdev_get_clocklist(dev, name);
+
+    qdev_init_clocklist(alias_dev, alias_name, ncl->output, ncl->clock);
+
+    return ncl->clock;
+}