intel/wifi: Add WGDS ACPI method for Geo Aware SAR

To comply with all relevant bodies throughout the world, SAR settings
take into account the lowest common denominator Tx power settings. This
setup may lead to non-optimal performance when the user location is in a
country that may allow higher power setting. The purpose of Wireless Geo
Delta Settings (WGDS) is to provide offset settings for FCC, Europe,
Japan and Rest of the world. These offsets would be added (by Intel wifi
driver) to the base SAR Tx Power as defined in WRDS and EWRD

BUG=b:65155728
BRANCH=none
TEST=WGDS ACPI table gets created as expected.

Change-Id: I4f602e3f95ff3545db6cc6e428beb9a36abd9296
Signed-off-by: Pratik Prajapati <pratikkumar.v.prajapati@intel.com>
Reviewed-on: https://review.coreboot.org/21098
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

1 files changed, 55 insertions, 0 deletions

diff --git a/src/drivers/intel/wifi/wifi.c b/src/drivers/intel/wifi/wifi.c
index 3ef66aad2a..4b96a0297c 100644
--- a/src/drivers/intel/wifi/wifi.c
+++ b/src/drivers/intel/wifi/wifi.c
@@ -2,6 +2,7 @@
  * This file is part of the coreboot project.
  *
  * Copyright (C) 2014 Vladimir Serbinenko
+ * Copyright (C) 2018 Intel Corp.
  *
  * 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
@@ -75,6 +76,7 @@ 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) {
@@ -135,6 +137,59 @@ static void emit_sar_acpi_structures(void)
 			acpigen_write_byte(sar_limits.sar_limit[i][j]);
 	acpigen_pop_len();
 	acpigen_pop_len();
+
+
+	if (!IS_ENABLED(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();
 }
 
 static void intel_wifi_fill_ssdt(struct device *dev)