dm: core: Create a struct for device runtime info

At present when driver model needs to change a device it simply updates
the struct udevice structure. But with of-platdata-inst most of the fields
are not modified at runtime. In fact, typically only the flags need to
change.

For systems running SPL from read-only memory it is convenient to separate
out the runtime information, so that the devices don't need to be copied
before being used.

Create a new udevice_rt table, similar to the existing driver_rt. For now
it just holds the flags, although they are not used in this patch.

Add a new Kconfig for the driver_rt data, since this is not needed when
of-platdata-inst is used.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/core/root.c b/drivers/core/root.c
index 3e52452..446ac2f 100644
--- a/drivers/core/root.c
+++ b/drivers/core/root.c
@@ -133,6 +133,18 @@
 {
 	DM_ROOT_NON_CONST = DM_DEVICE_GET(root);
 
+	if (CONFIG_IS_ENABLED(OF_PLATDATA_RT)) {
+		struct udevice_rt *urt;
+		int n_ents;
+
+		/* Allocate the udevice_rt table */
+		n_ents = ll_entry_count(struct udevice, udevice);
+		urt = calloc(n_ents, sizeof(struct udevice_rt));
+		if (!urt)
+			return log_msg_ret("urt", -ENOMEM);
+		gd_set_dm_udevice_rt(urt);
+	}
+
 	return 0;
 }
 
@@ -205,7 +217,7 @@
 {
 	int ret;
 
-	if (CONFIG_IS_ENABLED(OF_PLATDATA)) {
+	if (CONFIG_IS_ENABLED(OF_PLATDATA_DRIVER_RT)) {
 		struct driver_rt *dyn;
 		int n_ents;
 
diff --git a/dts/Kconfig b/dts/Kconfig
index e6bbdc5..99ce75e 100644
--- a/dts/Kconfig
+++ b/dts/Kconfig
@@ -338,6 +338,7 @@
 	bool "Generate platform data for use in SPL"
 	depends on SPL_OF_CONTROL
 	select DTOC
+	select SPL_OF_PLATDATA_DRIVER_RT if !SPL_OF_PLATDATA_INST
 	help
 	  For very constrained SPL environments the overhead of decoding
 	  device tree nodes and converting their contents into platform data
@@ -391,12 +392,22 @@
 	  struct udevice (at present just the flags) into a separate struct,
 	  which is allocated at runtime.
 
+config SPL_OF_PLATDATA_DRIVER_RT
+	bool
+	help
+	  Use a separate struct for driver runtime data.
+
+	  This enables the driver_rt information, used with of-platdata when
+	  of-platdata-inst is not used. It allows finding devices by their
+	  driver data.
+
 endif
 
 config TPL_OF_PLATDATA
 	bool "Generate platform data for use in TPL"
 	depends on TPL_OF_CONTROL
 	select DTOC
+	select TPL_OF_PLATDATA_DRIVER_RT if !TPL_OF_PLATDATA_INST
 	help
 	  For very constrained SPL environments the overhead of decoding
 	  device tree nodes and converting their contents into platform data
@@ -451,6 +462,15 @@
 	  struct udevice (at present just the flags) into a separate struct,
 	  which is allocated at runtime.
 
+config TPL_OF_PLATDATA_DRIVER_RT
+	bool
+	help
+	  Use a separate struct for driver runtime data.
+
+	  This enables the driver_rt information, used with of-platdata when
+	  of-platdata-inst is not used. It allows finding devices by their
+	  driver data.
+
 endif
 
 endmenu
diff --git a/include/asm-generic/global_data.h b/include/asm-generic/global_data.h
index c24f5e0..f6189ef 100644
--- a/include/asm-generic/global_data.h
+++ b/include/asm-generic/global_data.h
@@ -215,10 +215,14 @@
 	 * @uclass_root_s.
 	 */
 	struct list_head *uclass_root;
-# if CONFIG_IS_ENABLED(OF_PLATDATA)
+# if CONFIG_IS_ENABLED(OF_PLATDATA_DRIVER_RT)
 	/** @dm_driver_rt: Dynamic info about the driver */
 	struct driver_rt *dm_driver_rt;
 # endif
+#if CONFIG_IS_ENABLED(OF_PLATDATA_RT)
+	/** @dm_udevice_rt: Dynamic info about the udevice */
+	struct udevice_rt *dm_udevice_rt;
+# endif
 #endif
 #ifdef CONFIG_TIMER
 	/**
@@ -483,7 +487,7 @@
 #define gd_set_of_root(_root)
 #endif
 
-#if CONFIG_IS_ENABLED(OF_PLATDATA)
+#if CONFIG_IS_ENABLED(OF_PLATDATA_DRIVER_RT)
 #define gd_set_dm_driver_rt(dyn)	gd->dm_driver_rt = dyn
 #define gd_dm_driver_rt()		gd->dm_driver_rt
 #else
@@ -491,6 +495,14 @@
 #define gd_dm_driver_rt()		NULL
 #endif
 
+#if CONFIG_IS_ENABLED(OF_PLATDATA_RT)
+#define gd_set_dm_udevice_rt(dyn)	gd->dm_udevice_rt = dyn
+#define gd_dm_udevice_rt()		gd->dm_udevice_rt
+#else
+#define gd_set_dm_udevice_rt(dyn)
+#define gd_dm_udevice_rt()		NULL
+#endif
+
 #ifdef CONFIG_GENERATE_ACPI_TABLE
 #define gd_acpi_ctx()		gd->acpi_ctx
 #else
diff --git a/include/dm/device.h b/include/dm/device.h
index 9183356..8e16f2e 100644
--- a/include/dm/device.h
+++ b/include/dm/device.h
@@ -190,6 +190,21 @@
 #endif
 };
 
+/**
+ * udevice_rt - runtime information set up by U-Boot
+ *
+ * This is only used with OF_PLATDATA_RT
+ *
+ * There is one of these for every udevice in the linker list, indexed by
+ * the udevice_info idx value.
+ *
+ * @flags_: Flags for this device DM_FLAG_... (do not access outside driver
+ *	model)
+ */
+struct udevice_rt {
+	u32 flags_;
+};
+
 /* Maximum sequence number supported */
 #define DM_MAX_SEQ	999
 
diff --git a/test/dm/of_platdata.c b/test/dm/of_platdata.c
index f2b45b9..0f89c7a 100644
--- a/test/dm/of_platdata.c
+++ b/test/dm/of_platdata.c
@@ -147,7 +147,7 @@
 	uint i;
 
 	/* Skip this test if there is no platform data */
-	if (CONFIG_IS_ENABLED(OF_PLATDATA_INST))
+	if (!CONFIG_IS_ENABLED(OF_PLATDATA_DRIVER_RT))
 		return 0;
 
 	/* Record the indexes that are found */