[v2,20/39] acpi: Add a method to write tables for a device

diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts
index 5fa951ad4b..1204c14b07 100644
--- a/arch/sandbox/dts/test.dts
+++ b/arch/sandbox/dts/test.dts
@@ -210,6 +210,10 @@ 
 		compatible = "denx,u-boot-acpi-test";
 	};
 
+	acpi-test2 {
+		compatible = "denx,u-boot-acpi-test";
+	};
+
 	clocks {
 		clk_fixed: clk-fixed {
 			compatible = "fixed-clock";
diff --git a/drivers/core/acpi.c b/drivers/core/acpi.c
index 45542199f5..10bac38c1d 100644
--- a/drivers/core/acpi.c
+++ b/drivers/core/acpi.c
@@ -11,8 +11,17 @@ 
 #include <common.h>
 #include <dm.h>
 #include <dm/acpi.h>
+#include <dm/device-internal.h>
 #include <dm/root.h>
 
+/* Type of method to call */
+enum method_t {
+	METHOD_WRITE_TABLES,
+};
+
+/* Prototype for all methods */
+typedef int (*acpi_method)(const struct udevice *dev, struct acpi_ctx *ctx);
+
 int acpi_return_name(char *out_name, const char *name)
 {
 	strcpy(out_name, name);
@@ -30,3 +39,55 @@  int acpi_get_name(const struct udevice *dev, char *out_name)
 
 	return -ENOSYS;
 }
+
+acpi_method acpi_get_method(struct udevice *dev, enum method_t method)
+{
+	struct acpi_ops *aops;
+
+	aops = device_get_acpi_ops(dev);
+	if (aops) {
+		switch (method) {
+		case METHOD_WRITE_TABLES:
+			return aops->write_tables;
+		}
+	}
+
+	return NULL;
+}
+
+int acpi_recurse_method(struct acpi_ctx *ctx, struct udevice *parent,
+			enum method_t method)
+{
+	struct udevice *dev;
+	acpi_method func;
+	int ret;
+
+	func = acpi_get_method(parent, method);
+	if (func) {
+		log_debug("\n- %s %p\n", parent->name, func);
+		ret = device_ofdata_to_platdata(parent);
+		if (ret)
+			return log_msg_ret("ofdata", ret);
+		ret = func(parent, ctx);
+		if (ret)
+			return log_msg_ret("func", ret);
+	}
+	device_foreach_child(dev, parent) {
+		ret = acpi_recurse_method(ctx, dev, method);
+		if (ret)
+			return log_msg_ret("recurse", ret);
+	}
+
+	return 0;
+}
+
+int acpi_write_dev_tables(struct acpi_ctx *ctx)
+{
+	int ret;
+
+	log_debug("Writing device tables\n");
+	ret = acpi_recurse_method(ctx, dm_root(), METHOD_WRITE_TABLES);
+	log_debug("Writing finished, err=%d\n", ret);
+
+	return ret;
+}
diff --git a/include/dm/acpi.h b/include/dm/acpi.h
index 8d6c3fd424..dcfcf5c347 100644
--- a/include/dm/acpi.h
+++ b/include/dm/acpi.h
@@ -24,6 +24,17 @@ 
 
 #if !defined(__ACPI__)
 
+/**
+ * struct acpi_ctx - Context used for writing ACPI tables
+ *
+ * This contains a few useful pieces of information used when writing
+ *
+ * @current: Current address for writing
+ */
+struct acpi_ctx {
+	void *current;
+};
+
 /**
  * struct acpi_ops - ACPI operations supported by driver model
  */
@@ -38,6 +49,15 @@  struct acpi_ops {
 	 *	other error
 	 */
 	int (*get_name)(const struct udevice *dev, char *out_name);
+
+	/**
+	 * write_tables() - Write out any tables required by this device
+	 *
+	 * @dev: Device to write
+	 * @ctx: ACPI context to use
+	 * @return 0 if OK, -ve on error
+	 */
+	int (*write_tables)(const struct udevice *dev, struct acpi_ctx *ctx);
 };
 
 #define device_get_acpi_ops(dev)	((dev)->driver->acpi_ops)
@@ -72,6 +92,16 @@  int acpi_get_name(const struct udevice *dev, char *out_name);
  */
 int acpi_return_name(char *out_name, const char *name);
 
+/**
+ * acpi_write_dev_tables() - Write ACPI tables required by devices
+ *
+ * This scans through all devices and tells them to write any tables they want
+ * to write.
+ *
+ * @return 0 if OK, -ve if any device returned an error
+ */
+int acpi_write_dev_tables(struct acpi_ctx *ctx);
+
 #endif /* __ACPI__ */
 
 #endif
diff --git a/test/dm/acpi.c b/test/dm/acpi.c
index e28ebf4f90..b87fbd16b0 100644
--- a/test/dm/acpi.c
+++ b/test/dm/acpi.c
@@ -15,6 +15,19 @@ 
 #include <test/ut.h>
 
 #define ACPI_TEST_DEV_NAME	"ABCD"
+#define BUF_SIZE		4096
+
+static int testacpi_write_tables(const struct udevice *dev,
+				 struct acpi_ctx *ctx)
+{
+	struct acpi_dmar *dmar;
+
+	dmar = (struct acpi_dmar *)ctx->current;
+	acpi_create_dmar(dmar, DMAR_INTR_REMAP);
+	ctx->current += sizeof(struct acpi_dmar);
+
+	return 0;
+}
 
 static int testacpi_get_name(const struct udevice *dev, char *out_name)
 {
@@ -23,6 +36,7 @@  static int testacpi_get_name(const struct udevice *dev, char *out_name)
 
 struct acpi_ops testacpi_ops = {
 	.get_name	= testacpi_get_name,
+	.write_tables	= testacpi_write_tables,
 };
 
 static const struct udevice_id testacpi_ids[] = {
@@ -109,3 +123,32 @@  static int dm_test_acpi_fill_header(struct unit_test_state *uts)
 	return 0;
 }
 DM_TEST(dm_test_acpi_fill_header, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+/* Test ACPI write_tables() */
+static int dm_test_acpi_write_tables(struct unit_test_state *uts)
+{
+	struct acpi_dmar *dmar;
+	struct acpi_ctx ctx;
+	void *buf;
+
+	buf = malloc(BUF_SIZE);
+	ut_assertnonnull(buf);
+
+	ctx.current = buf;
+	ut_assertok(acpi_write_dev_tables(&ctx));
+	dmar = buf;
+
+	/*
+	 * We should have two dmar tables, one for each "denx,u-boot-acpi-test"
+	 * device
+	 */
+	ut_asserteq_ptr(dmar + 2, ctx.current);
+	ut_asserteq(DMAR_INTR_REMAP, dmar->flags);
+	ut_asserteq(32 - 1, dmar->host_address_width);
+
+	ut_asserteq(DMAR_INTR_REMAP, dmar[1].flags);
+	ut_asserteq(32 - 1, dmar[1].host_address_width);
+
+	return 0;
+}
+DM_TEST(dm_test_acpi_write_tables, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);