drivers/wifi: Add generic WiFi driver

Add generic WiFi driver to support common device operations across
multiple types of WiFi controller.

BUG=None
BRANCH=None
TEST=Boot to ChromeOS. Ensure that the SSDT table contains SAR tables
and wakeup GPE information. Ensure that the SSDT table is same after the
change.

Change-Id: Ica5edf95a37c8ed60f7e159d94fd58af5d41c0ef
Signed-off-by: Karthikeyan Ramasubramanian <kramasub@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/33155
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

4 files changed, 354 insertions, 0 deletions

diff --git a/src/drivers/wifi/Kconfig b/src/drivers/wifi/Kconfig
new file mode 100644
index 0000000000..9b87f844f6
--- /dev/null
+++ b/src/drivers/wifi/Kconfig
@@ -0,0 +1,57 @@
+config DRIVERS_GENERIC_WIFI
+	bool
+	default n
+	depends on HAVE_ACPI_TABLES
+	help
+	  When enabled, add identifiers in ACPI tables that are common
+	  to WiFi chipsets from multiple vendors.
+
+if DRIVERS_GENERIC_WIFI
+
+config USE_SAR
+	bool
+	default n
+	help
+	  Enable it when wifi driver uses SAR configuration feature.
+	  VPD entry "wifi_sar" is read to get SAR settings, if its
+	  not found driver may look into CBFS for default settigs.
+	  WIFI_SAR_CBFS is option to enable CBFS lookup.
+
+config SAR_ENABLE
+	bool
+	default n
+	depends on USE_SAR
+
+config DSAR_ENABLE
+	bool
+	default n
+	depends on USE_SAR
+
+config GEO_SAR_ENABLE
+	bool
+	default n
+	depends on USE_SAR
+
+config WIFI_SAR_CBFS
+	bool "Enable SAR table addition to CBFS"
+	default n
+	depends on USE_SAR
+	help
+	 wifi driver would look for "wifi_sar" vpd key and load SAR settings from
+	 it, if the vpd key is not found then the driver tries to look for sar
+	 settings from CBFS with file name wifi_sar_defaults.hex.
+	 So OEM/ODM can override wifi sar with VPD.
+
+config WIFI_SAR_CBFS_FILEPATH
+	string "The cbfs file which has WIFI SAR defaults"
+	depends on WIFI_SAR_CBFS
+	default "src/mainboard/$(MAINBOARDDIR)/wifi_sar_defaults.hex"
+
+config DSAR_SET_NUM
+	hex "Number of SAR sets when D-SAR is enabled"
+	default 0x3
+	depends on USE_SAR
+	help
+	  There can be up to 3 optional SAR table sets.
+
+endif # DRIVERS_GENERIC_WIFI
diff --git a/src/drivers/wifi/Makefile.inc b/src/drivers/wifi/Makefile.inc
new file mode 100644
index 0000000000..d37015c7d3
--- /dev/null
+++ b/src/drivers/wifi/Makefile.inc
@@ -0,0 +1 @@
+ramstage-$(CONFIG_DRIVERS_GENERIC_WIFI) += generic.c
diff --git a/src/drivers/wifi/generic.c b/src/drivers/wifi/generic.c
new file mode 100644
index 0000000000..b593ffe8bc
--- /dev/null
+++ b/src/drivers/wifi/generic.c
@@ -0,0 +1,245 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2019 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 or (at your option)
+ * any later version 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/pci_def.h>
+#include <sar.h>
+#include <string.h>
+#include <wrdd.h>
+#include "generic_wifi.h"
+
+/* WRDS Spec Revision */
+#define WRDS_REVISION 0x0
+
+/* EWRD Spec Revision */
+#define EWRD_REVISION 0x0
+
+/* WRDS Domain type */
+#define WRDS_DOMAIN_TYPE_WIFI 0x7
+
+/* EWRD Domain type */
+#define EWRD_DOMAIN_TYPE_WIFI 0x7
+
+/* WGDS Domain type */
+#define WGDS_DOMAIN_TYPE_WIFI 0x7
+
+/*
+ * WIFI ACPI NAME = "WF" + hex value of last 8 bits of dev_path_encode + '\0'
+ * The above representation returns unique and consistent name every time
+ * generate_wifi_acpi_name is invoked. The last 8 bits of dev_path_encode is
+ * chosen since it contains the bus address of the device.
+ */
+#define WIFI_ACPI_NAME_MAX_LEN 5
+
+__weak
+int get_wifi_sar_limits(struct wifi_sar_limits *sar_limits)
+{
+	return -1;
+}
+
+static void emit_sar_acpi_structures(void)
+{
+	int i, j, package_size;
+	struct wifi_sar_limits sar_limits;
+	struct wifi_sar_delta_table *wgds;
+
+	/* Retrieve the sar limits data */
+	if (get_wifi_sar_limits(&sar_limits) < 0) {
+		printk(BIOS_ERR, "Error: failed from getting SAR limits!\n");
+		return;
+	}
+
+	/*
+	 * Name ("WRDS", Package () {
+	 *   Revision,
+	 *   Package () {
+	 *     Domain Type,	// 0x7:WiFi
+	 *     WiFi SAR BIOS,	// BIOS SAR Enable/disable
+	 *     SAR Table Set	// Set#1 of SAR Table (10 bytes)
+	 *   }
+	 * })
+	 */
+	acpigen_write_name("WRDS");
+	acpigen_write_package(2);
+	acpigen_write_dword(WRDS_REVISION);
+	/* Emit 'Domain Type' + 'WiFi SAR BIOS' + 10 bytes for Set#1 */
+	package_size = 1 + 1 + BYTES_PER_SAR_LIMIT;
+	acpigen_write_package(package_size);
+	acpigen_write_dword(WRDS_DOMAIN_TYPE_WIFI);
+	acpigen_write_dword(CONFIG(SAR_ENABLE));
+	for (i = 0; i < BYTES_PER_SAR_LIMIT; i++)
+		acpigen_write_byte(sar_limits.sar_limit[0][i]);
+	acpigen_pop_len();
+	acpigen_pop_len();
+
+	/*
+	 * Name ("EWRD", Package () {
+	 *   Revision,
+	 *   Package () {
+	 *     Domain Type,		// 0x7:WiFi
+	 *     Dynamic SAR Enable,	// Dynamic SAR Enable/disable
+	 *     Extended SAR sets,	// Number of optional SAR table sets
+	 *     SAR Table Set,		// Set#2 of SAR Table (10 bytes)
+	 *     SAR Table Set,		// Set#3 of SAR Table (10 bytes)
+	 *     SAR Table Set		// Set#4 of SAR Table (10 bytes)
+	 *   }
+	 * })
+	 */
+	acpigen_write_name("EWRD");
+	acpigen_write_package(2);
+	acpigen_write_dword(EWRD_REVISION);
+	/*
+	 * Emit 'Domain Type' + "Dynamic SAR Enable' + 'Extended SAR sets'
+	 * + number of bytes for Set#2 & 3 & 4
+	 */
+	package_size = 1 + 1 + 1 + (NUM_SAR_LIMITS - 1) * BYTES_PER_SAR_LIMIT;
+	acpigen_write_package(package_size);
+	acpigen_write_dword(EWRD_DOMAIN_TYPE_WIFI);
+	acpigen_write_dword(CONFIG(DSAR_ENABLE));
+	acpigen_write_dword(CONFIG_DSAR_SET_NUM);
+	for (i = 1; i < NUM_SAR_LIMITS; i++)
+		for (j = 0; j < BYTES_PER_SAR_LIMIT; j++)
+			acpigen_write_byte(sar_limits.sar_limit[i][j]);
+	acpigen_pop_len();
+	acpigen_pop_len();
+
+
+	if (!CONFIG(GEO_SAR_ENABLE))
+		return;
+
+	/*
+	 * Name ("WGDS", Package() {
+	 *  Revision,
+	 *  Package() {
+	 *   DomainType,                         // 0x7:WiFi
+	 *   WgdsWiFiSarDeltaGroup1PowerMax1,    // Group 1 FCC 2400 Max
+	 *   WgdsWiFiSarDeltaGroup1PowerChainA1, // Group 1 FCC 2400 A Offset
+	 *   WgdsWiFiSarDeltaGroup1PowerChainB1, // Group 1 FCC 2400 B Offset
+	 *   WgdsWiFiSarDeltaGroup1PowerMax2,    // Group 1 FCC 5200 Max
+	 *   WgdsWiFiSarDeltaGroup1PowerChainA2, // Group 1 FCC 5200 A Offset
+	 *   WgdsWiFiSarDeltaGroup1PowerChainB2, // Group 1 FCC 5200 B Offset
+	 *   WgdsWiFiSarDeltaGroup2PowerMax1,    // Group 2 EC Jap 2400 Max
+	 *   WgdsWiFiSarDeltaGroup2PowerChainA1, // Group 2 EC Jap 2400 A Offset
+	 *   WgdsWiFiSarDeltaGroup2PowerChainB1, // Group 2 EC Jap 2400 B Offset
+	 *   WgdsWiFiSarDeltaGroup2PowerMax2,    // Group 2 EC Jap 5200 Max
+	 *   WgdsWiFiSarDeltaGroup2PowerChainA2, // Group 2 EC Jap 5200 A Offset
+	 *   WgdsWiFiSarDeltaGroup2PowerChainB2, // Group 2 EC Jap 5200 B Offset
+	 *   WgdsWiFiSarDeltaGroup3PowerMax1,    // Group 3 ROW 2400 Max
+	 *   WgdsWiFiSarDeltaGroup3PowerChainA1, // Group 3 ROW 2400 A Offset
+	 *   WgdsWiFiSarDeltaGroup3PowerChainB1, // Group 3 ROW 2400 B Offset
+	 *   WgdsWiFiSarDeltaGroup3PowerMax2,    // Group 3 ROW 5200 Max
+	 *   WgdsWiFiSarDeltaGroup3PowerChainA2, // Group 3 ROW 5200 A Offset
+	 *   WgdsWiFiSarDeltaGroup3PowerChainB2, // Group 3 ROW 5200 B Offset
+	 *  }
+	 * })
+	 */
+
+	wgds = &sar_limits.wgds;
+	acpigen_write_name("WGDS");
+	acpigen_write_package(2);
+	acpigen_write_dword(wgds->version);
+	/* Emit 'Domain Type' +
+	 * Group specific delta of power (6 bytes * NUM_WGDS_SAR_GROUPS)
+	 */
+	package_size = sizeof(sar_limits.wgds.group) + 1;
+	acpigen_write_package(package_size);
+	acpigen_write_dword(WGDS_DOMAIN_TYPE_WIFI);
+	for (i = 0; i < SAR_NUM_WGDS_GROUPS; i++) {
+		acpigen_write_byte(wgds->group[i].power_max_2400mhz);
+		acpigen_write_byte(wgds->group[i].power_chain_a_2400mhz);
+		acpigen_write_byte(wgds->group[i].power_chain_b_2400mhz);
+		acpigen_write_byte(wgds->group[i].power_max_5200mhz);
+		acpigen_write_byte(wgds->group[i].power_chain_a_5200mhz);
+		acpigen_write_byte(wgds->group[i].power_chain_b_5200mhz);
+	}
+
+	acpigen_pop_len();
+	acpigen_pop_len();
+}
+
+void generic_wifi_fill_ssdt(struct device *dev,
+			    const struct generic_wifi_config *config)
+{
+	const char *path;
+	u32 address;
+
+	if (!dev->enabled)
+		return;
+
+	path = acpi_device_path(dev->bus->dev);
+	if (!path)
+		return;
+
+	/* Device */
+	acpigen_write_scope(path);
+	acpigen_write_device(acpi_device_name(dev));
+	acpigen_write_name_integer("_UID", 0);
+	if (dev->chip_ops)
+		acpigen_write_name_string("_DDN", dev->chip_ops->name);
+
+	/* Address */
+	address = PCI_SLOT(dev->path.pci.devfn) & 0xffff;
+	address <<= 16;
+	address |= PCI_FUNC(dev->path.pci.devfn) & 0xffff;
+	acpigen_write_name_dword("_ADR", address);
+
+	/* Wake capabilities */
+	if (config)
+		acpigen_write_PRW(config->wake, config->maxsleep);
+
+	/* Fill regulatory domain structure */
+	if (CONFIG(HAVE_REGULATORY_DOMAIN)) {
+		/*
+		 * Name ("WRDD", Package () {
+		 *   WRDD_REVISION, // Revision
+		 *   Package () {
+		 *     WRDD_DOMAIN_TYPE_WIFI,   // Domain Type, 7:WiFi
+		 *     wifi_regulatory_domain() // Country Identifier
+		 *   }
+		 * })
+		 */
+		acpigen_write_name("WRDD");
+		acpigen_write_package(2);
+		acpigen_write_integer(WRDD_REVISION);
+		acpigen_write_package(2);
+		acpigen_write_dword(WRDD_DOMAIN_TYPE_WIFI);
+		acpigen_write_dword(wifi_regulatory_domain());
+		acpigen_pop_len();
+		acpigen_pop_len();
+	}
+
+	/* Fill Wifi sar related ACPI structures */
+	if (CONFIG(USE_SAR))
+		emit_sar_acpi_structures();
+
+	acpigen_pop_len(); /* Device */
+	acpigen_pop_len(); /* Scope */
+
+	printk(BIOS_INFO, "%s.%s: %s %s\n", path, acpi_device_name(dev),
+	       dev->chip_ops ? dev->chip_ops->name : "", dev_path(dev));
+}
+
+const char *generic_wifi_acpi_name(const struct device *dev)
+{
+	static char wifi_acpi_name[WIFI_ACPI_NAME_MAX_LEN];
+
+	snprintf(wifi_acpi_name, sizeof(wifi_acpi_name), "WF%02x",
+		 (dev_path_encode(dev) & 0xff));
+	return wifi_acpi_name;
+}
diff --git a/src/drivers/wifi/generic_wifi.h b/src/drivers/wifi/generic_wifi.h
new file mode 100644
index 0000000000..5f17c3e297
--- /dev/null
+++ b/src/drivers/wifi/generic_wifi.h
@@ -0,0 +1,51 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2019 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_WIFI_H_
+#define _GENERIC_WIFI_H_
+
+/**
+ * struct generic_wifi_config - Data structure to contain common wifi config
+ * @wake: Wake pin for ACPI _PRW
+ * @maxsleep: Maximum sleep state to wake from
+ */
+struct generic_wifi_config {
+	unsigned int wake;
+	unsigned int maxsleep;
+};
+
+/**
+ * wifi_fill_ssdt() - Fill ACPI SSDT table for WiFi controller
+ * @dev: Device structure corresponding to WiFi controller.
+ * @config: Common wifi config required to fill ACPI SSDT table.
+ *
+ * This function implements common device operation to help fill ACPI SSDT
+ * table for WiFi controller.
+ */
+void generic_wifi_fill_ssdt(struct device *dev,
+			    const struct generic_wifi_config *config);
+
+/**
+ * wifi_acpi_name() - Get ACPI name for WiFi controller
+ * @dev: Device structure corresponding to WiFi controller.
+ *
+ * This function implements common device operation to get the ACPI name for
+ * WiFi controller.
+ *
+ * Return: string representing the ACPI name for WiFi controller.
+ */
+const char *generic_wifi_acpi_name(const struct device *dev);
+
+#endif /* _GENERIC_WIFI_H_ */