dde_linux: enhance clock infrastructure

Issue #5036

repos/dde_linux/src/lib/lx_emul/clock.cc

@@ -15,8 +15,21 @@
 #include <lx_kit/env.h>
 #include <lx_emul/clock.h>
 
-extern "C" int of_device_is_compatible(const struct device_node * node,
+/*
-                                       const char * compat);
+ * CONFIG_OF is normally disabled on PC thus of_device_is_compatible() should
+ * be "static inline" not "extern" (see include/linux/of.h), thus enable this
+ * function only if not building for x86.
+ */
+extern "C" int of_device_is_compatible(const struct device_node * node, const char * compat);
+static int _of_device_is_compatible(const struct device_node * node, const char * compat)
+{
+#if defined(__x86_64__) || defined(__i386__)
+	(void)node; (void)compat;
+	return 0;
+#else
+	return of_device_is_compatible(node, compat);
+#endif
+}
 
 struct clk * lx_emul_clock_get(const struct device_node * node,
                                const char * name)
@@ -26,7 +39,7 @@ struct clk * lx_emul_clock_get(const struct device_node * node,
 	struct clk * ret = nullptr;
 
 	env().devices.for_each([&] (Device & d) {
-		if (!of_device_is_compatible(node, d.compatible()))
+		if (!_of_device_is_compatible(node, d.compatible()))
 			return;
 		ret = name ? d.clock(name) : d.clock(0U);
 		if (!ret) warning("No clock ", name, " found for device ", d.name());

repos/dde_linux/src/lib/lx_emul/shadow/drivers/clk/clk-devres.c

@@ -0,0 +1,26 @@
+/*
+ * \brief  Replaces drivers/clk/clk-devres.c
+ * \author Christian Helmuth
+ * \date   2023-06-13
+ */
+
+/*
+ * Copyright (C) 2023 Genode Labs GmbH
+ *
+ * This file is distributed under the terms of the GNU General Public License
+ * version 2.
+ */
+
+#include <linux/clk.h>
+
+
+struct clk *devm_clk_get(struct device *dev, const char *id)
+{
+	return clk_get(dev, id);
+}
+
+
+struct clk *devm_clk_get_optional(struct device *dev,const char *id)
+{
+	return devm_clk_get(dev, id);
+}

repos/dde_linux/src/lib/lx_emul/shadow/drivers/clk/clk.c

@@ -52,3 +52,8 @@ struct of_device_id;
 
 void of_clk_init(const struct of_device_id *matches) { }
 
+
+const char *__clk_get_name(const struct clk *clk)
+{
+	return "unknown-clk";
+}