drivers/generic: Add support for providing DSD properties

This change adds support in generic device driver to add properties to
DSD table. This driver can be used by all generic devices that do not
need any special handling other than simply adding device properties
to be used by OS.

BUG=b:112888584

Change-Id: I0ca6614f1ef322397618676bbf6da898bef18990
Signed-off-by: Furquan Shaikh <furquan@google.com>
Reviewed-on: https://review.coreboot.org/28796
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/drivers/generic/generic/Kconfig

@@ -1,2 +1,3 @@
 config DRIVERS_GENERIC_GENERIC
 	bool
+	depends on HAVE_ACPI_TABLES

src/drivers/generic/generic/Makefile.inc

@@ -1 +1 @@
-# Empty
+ramstage-$(CONFIG_DRIVERS_GENERIC_GENERIC) += generic.c

src/drivers/generic/generic/chip.h

@@ -0,0 +1,48 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2018 Google LLC.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __GENERIC_GENERIC_CHIP_H__
+#define __GENERIC_GENERIC_CHIP_H__
+
+#if IS_ENABLED(CONFIG_HAVE_ACPI_TABLES)
+
+#include <arch/acpi_device.h>
+
+#define MAX_GENERIC_PROPERTY_LIST 10
+
+struct drivers_generic_generic_config {
+	const char *hid;	/* ACPI _HID (required) */
+	const char *cid;	/* ACPI _CID */
+	const char *name;	/* ACPI Device Name */
+	/*
+	 * Autogenerated ACPI Device Name if name is not provided in
+	 * devicetree.
+	 */
+	char autogen_name[5];
+	const char *desc;	/* ACPI _DDN */
+	unsigned int uid;	/* ACPI _UID */
+
+	/* Generic properties for exporting device-specific data to the OS */
+	struct acpi_dp property_list[MAX_GENERIC_PROPERTY_LIST];
+	int property_count;
+};
+
+#else /* CONFIG_HAVE_ACPI_TABLES */
+
+struct drivers_generic_generic_config { };
+
+#endif /* !CONFIG_HAVE_ACPI_TABLES */
+
+#endif /* __GENERIC_GENERIC_CHIP_H__ */

src/drivers/generic/generic/generic.c

@@ -0,0 +1,98 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2018 Google LLC
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <arch/acpi_device.h>
+#include <arch/acpigen.h>
+#include <console/console.h>
+#include <device/device.h>
+#include <device/path.h>
+#include <stdint.h>
+#include <string.h>
+#include "chip.h"
+
+static void generic_dev_fill_ssdt_generator(struct device *dev)
+{
+	struct acpi_dp *dsd;
+	struct drivers_generic_generic_config *config = dev->chip_info;
+
+	if (!dev->enabled || !config)
+		return;
+
+	if (!config->hid) {
+		printk(BIOS_ERR, "%s: ERROR: _HID required\n", dev_path(dev));
+		return;
+	}
+
+	acpigen_write_scope(acpi_device_scope(dev));
+	acpigen_write_device(acpi_device_name(dev));
+	acpigen_write_name_string("_HID", config->hid);
+	if (config->cid)
+		acpigen_write_name_string("_CID", config->cid);
+	acpigen_write_name_integer("_UID", config->uid);
+	acpigen_write_name_string("_DDN", config->desc);
+	acpigen_write_STA(acpi_device_status(dev));
+
+	dsd = acpi_dp_new_table("_DSD");
+	acpi_dp_add_property_list(dsd, config->property_list,
+				  config->property_count);
+	acpi_dp_write(dsd);
+
+	acpigen_pop_len();	/* Device */
+	acpigen_pop_len();	/* Scope */
+
+	printk(BIOS_INFO, "%s: %s at %s\n", acpi_device_path(dev),
+	       config->desc ? : dev->chip_ops->name, dev_path(dev));
+}
+
+static char *generic_autogen_name(struct drivers_generic_generic_config *config)
+{
+	char *name = &config->autogen_name[0];
+	static unsigned int id;
+
+	if (name[0] != '\0')
+		return name;
+
+	snprintf(name, sizeof(name), "G%03.3X", id++);
+	name[4] = '\0';
+	return name;
+}
+
+static const char *generic_dev_acpi_name(const struct device *dev)
+{
+	struct drivers_generic_generic_config *config = dev->chip_info;
+
+	if (config->name)
+		return config->name;
+
+	return generic_autogen_name(config);
+}
+
+static struct device_operations generic_dev_ops = {
+	.read_resources			= DEVICE_NOOP,
+	.set_resources			= DEVICE_NOOP,
+	.enable_resources		= DEVICE_NOOP,
+	.acpi_name			= &generic_dev_acpi_name,
+	.acpi_fill_ssdt_generator	= &generic_dev_fill_ssdt_generator,
+};
+
+static void generic_dev_enable(struct device *dev)
+{
+	dev->ops = &generic_dev_ops;
+}
+
+struct chip_operations drivers_generic_generic_ops = {
+	CHIP_NAME("Generic Device")
+	.enable_dev = &generic_dev_enable
+};