Add new finalize functions for devices and chips

Many chipset devices require additional configuration after
device init. It is not uncommmon for a device early in the devicetree
list to need to change a setting after a device later in the tree does
PCI init. A final function call has been added to device ops to handle
this case. It is called prior to coreboot table setup.

Another problem that is often seen is that the chipset or mainboard
need to do some final cleanup just before loading the OS. The chip
finalize has been added for this case. It is call after all coreboot
tables are setup and the payload is ready to be called.

Similar functionality could be implemented with the hardwaremain
states, but those don't fit well in the device tree function pointer
structure and should be used sparingly.

Change-Id: Ib37cce104ae41ec225a8502942d85e54d99ea75f
Signed-off-by: Marc Jones <marc.jones@se-eng.com>
Reviewed-on: http://review.coreboot.org/4012
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@google.com>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

src/device/device.c

@@ -72,6 +72,26 @@ void dev_initialize_chips(void)
 	}
 }
 
+/**
+ * Finalize all chips of statically known devices.
+ *
+ * This is the last call before calling the payload. This is a good place
+ * to lock registers or other final cleanup.
+ */
+void dev_finalize_chips(void)
+{
+	struct device *dev;
+
+	for (dev = all_devices; dev; dev = dev->next) {
+		/* Initialize chip if we haven't yet. */
+		if (dev->chip_ops && dev->chip_ops->final &&
+				!dev->chip_ops->finalized) {
+			dev->chip_ops->final(dev->chip_info);
+			dev->chip_ops->finalized = 1;
+		}
+	}
+}
+
 DECLARE_SPIN_LOCK(dev_lock)
 
 #if CONFIG_GFXUMA
@@ -1167,3 +1187,58 @@ void dev_initialize(void)
 	printk(BIOS_INFO, "Devices initialized\n");
 	show_all_devs(BIOS_SPEW, "After init.");
 }
+
+/**
+ * Finalize a specific device.
+ *
+ * The parent should be finalized first to avoid having an ordering problem.
+ * This is done by calling the parent's final() method before its childrens'
+ * final() methods.
+ *
+ * @param dev The device to be initialized.
+ */
+static void final_dev(struct device *dev)
+{
+	if (!dev->enabled)
+		return;
+
+	if (dev->ops && dev->ops->final) {
+		printk(BIOS_DEBUG, "%s final\n", dev_path(dev));
+		dev->ops->final(dev);
+	}
+}
+
+static void final_link(struct bus *link)
+{
+	struct device *dev;
+	struct bus *c_link;
+
+	for (dev = link->children; dev; dev = dev->sibling)
+		final_dev(dev);
+
+	for (dev = link->children; dev; dev = dev->sibling) {
+		for (c_link = dev->link_list; c_link; c_link = c_link->next)
+			final_link(c_link);
+	}
+}
+/**
+ * Finalize all devices in the global device tree.
+ *
+ * Starting at the root device, call the device's final() method to do
+ * device-specific cleanup, then call each child's final() method.
+ */
+void dev_finalize(void)
+{
+	struct bus *link;
+
+	printk(BIOS_INFO, "Finalize devices...\n");
+
+	/* First call the mainboard finalize. */
+	final_dev(&dev_root);
+
+	/* Now finalize everything. */
+	for (link = dev_root.link_list; link; link = link->next)
+		final_link(link);
+
+	printk(BIOS_INFO, "Devices finalized\n");
+}

src/include/device/device.h

@@ -22,7 +22,9 @@ struct pnp_mode_ops;
 struct chip_operations {
 	void (*enable_dev)(struct device *dev);
 	void (*init)(void *chip_info);
+	void (*final)(void *chip_info);
 	unsigned int initialized : 1;
+	unsigned int finalized : 1;
 	const char *name;
 };
 
@@ -35,6 +37,7 @@ struct device_operations {
 	void (*set_resources)(device_t dev);
 	void (*enable_resources)(device_t dev);
 	void (*init)(device_t dev);
+	void (*final)(device_t dev);
 	unsigned int (*scan_bus)(device_t bus, unsigned int max);
 	void (*enable)(device_t dev);
 	void (*disable)(device_t dev);
@@ -140,6 +143,8 @@ void dev_configure(void);
 void dev_enable(void);
 void dev_initialize(void);
 void dev_optimize(void);
+void dev_finalize(void);
+void dev_finalize_chips(void);
 
 /* Generic device helper functions */
 int reset_bus(struct bus *bus);

src/lib/hardwaremain.c

@@ -175,6 +175,7 @@ static boot_state_t bs_dev_init(void *arg)
 
 static boot_state_t bs_post_device(void *arg)
 {
+	dev_finalize();
 	timestamp_add_now(TS_DEVICE_DONE);
 
 	timestamp_reinit();
@@ -217,6 +218,8 @@ static boot_state_t bs_write_tables(void *arg)
 	 */
 	write_tables();
 
+	dev_finalize_chips();
+
 	return BS_PAYLOAD_LOAD;
 }