dm: core: Add basic ACPI support

ACPI (Advanced Configuration and Power Interface) is a standard for
specifying information about a platform. It is a little like device
tree but the bindings are part of the specification and it supports an
interpreted bytecode language.

Driver model does not use ACPI for U-Boot's configuration, but it is
convenient to have it support generation of ACPI tables for passing to
Linux, etc.

As a starting point, add an optional set of ACPI operations to each
device. Initially only a single operation is available, to obtain the
ACPI name for the device. More operations are added later.

Enable ACPI for sandbox to ensure build coverage and so that we can add
tests.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Wolfgang Wallner <wolfgang.wallner@br-automation.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

1 files changed, 33 insertions, 0 deletions

diff --git a/drivers/core/acpi.c b/drivers/core/acpi.c
new file mode 100644
index 0000000000..ba50d688fe
--- /dev/null
+++ b/drivers/core/acpi.c
@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Core driver model support for ACPI table generation
+ *
+ * Copyright 2019 Google LLC
+ * Written by Simon Glass <sjg@chromium.org>
+ */
+
+#define LOG_CATEOGRY	LOGC_ACPI
+
+#include <common.h>
+#include <dm.h>
+#include <dm/acpi.h>
+#include <dm/root.h>
+
+int acpi_copy_name(char *out_name, const char *name)
+{
+	strncpy(out_name, name, ACPI_NAME_LEN);
+	out_name[ACPI_NAME_LEN] = '\0';
+
+	return 0;
+}
+
+int acpi_get_name(const struct udevice *dev, char *out_name)
+{
+	struct acpi_ops *aops;
+
+	aops = device_get_acpi_ops(dev);
+	if (aops && aops->get_name)
+		return aops->get_name(dev, out_name);
+
+	return -ENOSYS;
+}