drivers/wifi: Support Bluetooth BiQuad Bypass Filter

This feature provides ability to identify non-LTE platform and disable
BiQuad Bypass filter logic in hardware for Bluetooth usecases reducing
device power consumption.

The implementation follows document 559910 Intel Connectivity
Platforms BIOS Guideline revision 9.2 specification.

BUG=b:346600091
TEST=BBFB method is added to the bluetooth companion device and
     return the data supplied by the SAR binary blob

Change-Id: Iebe95815c944d045f4cf686abcd1874a8a45e213
Signed-off-by: Jeremy Compostella <jeremy.compostella@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/84942
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Subrata Banik <subratabanik@google.com>
Reviewed-by: Elyes Haouas <ehaouas@noos.fr>
Reviewed-by: Kapil Porwal <kapilporwal@google.com>

3 files changed, 53 insertions, 1 deletions

diff --git a/src/drivers/wifi/generic/acpi.c b/src/drivers/wifi/generic/acpi.c
index 0a5bee728f..4be43ffe43 100644
--- a/src/drivers/wifi/generic/acpi.c
+++ b/src/drivers/wifi/generic/acpi.c
@@ -701,6 +701,41 @@ static void sar_emit_bpag(const struct bpag_profile *bpag)
 	acpigen_write_package_end();
 }
 
+static void sar_emit_bbfb(const struct bbfb_profile *bbfb)
+{
+	if (bbfb == NULL)
+		return;
+
+	/*
+	 * Name ("BBFB", Package () {
+	 *   Revision,
+	 *   Package () {
+	 *     Domain Type,			// 0x12:Bluetooth
+	 *     By Pass Enabled			// Enable ByPass
+	 *   }
+	 * })
+	 */
+	if (bbfb->revision != BBFB_REVISION) {
+		printk(BIOS_ERR, "Unsupported BBFB table revision: %d\n",
+		       bbfb->revision);
+		return;
+	}
+
+	acpigen_write_name("BBFB");
+	acpigen_write_package(2);
+	acpigen_write_dword(bbfb->revision);
+
+	/*
+	 * Emit 'Domain Type' + 'Enable ByPass'
+	 */
+	acpigen_write_package(2);
+	acpigen_write_dword(DOMAIN_TYPE_BLUETOOTH);
+	acpigen_write_dword(bbfb->enable_quad_filter_bypass);
+
+	acpigen_write_package_end();
+	acpigen_write_package_end();
+}
+
 static void emit_wifi_sar_acpi_structures(const struct device *dev,
 					  union wifi_sar_limits *sar_limits)
 {
@@ -834,6 +869,7 @@ static void wifi_ssdt_write_properties(const struct device *dev, const char *sco
 			acpigen_write_scope(path);
 			sar_emit_brds(sar_limits.bsar);
 			sar_emit_bpag(sar_limits.bpag);
+			sar_emit_bbfb(sar_limits.bbfb);
 			acpigen_write_scope_end();
 		} else {
 			printk(BIOS_ERR, "Failed to get %s Bluetooth companion ACPI path\n",
diff --git a/src/include/sar.h b/src/include/sar.h
index b9c83c3a05..0609bd34ef 100644
--- a/src/include/sar.h
+++ b/src/include/sar.h
@@ -9,11 +9,12 @@
 #define MAX_DENYLIST_ENTRY	16
 #define MAX_DSAR_SET_COUNT	3
 #define MAX_GEO_OFFSET_REVISION	3
-#define MAX_PROFILE_COUNT	8
+#define MAX_PROFILE_COUNT	9
 #define MAX_SAR_REVISION	2
 #define BSAR_REVISION		1
 #define WBEM_REVISION		0
 #define BPAG_REVISION		2
+#define BBFB_REVISION		1
 #define REVISION_SIZE		1
 #define SAR_REV0_CHAINS_COUNT	2
 #define SAR_REV0_SUBBANDS_COUNT	5
@@ -87,6 +88,11 @@ struct bpag_profile {
 	uint32_t antenna_gain_country_enablement;
 } __packed;
 
+struct bbfb_profile {
+	uint8_t revision;
+	uint8_t enable_quad_filter_bypass;
+} __packed;
+
 struct sar_header {
 	char marker[SAR_STR_PREFIX_SIZE];
 	uint8_t version;
@@ -104,6 +110,7 @@ union wifi_sar_limits {
 		struct bsar_profile *bsar;
 		struct wbem_profile *wbem;
 		struct bpag_profile *bpag;
+		struct bbfb_profile *bbfb;
 	};
 	void *profile[MAX_PROFILE_COUNT];
 };
diff --git a/src/vendorcode/google/chromeos/sar.c b/src/vendorcode/google/chromeos/sar.c
index dcf647398e..8d19f00222 100644
--- a/src/vendorcode/google/chromeos/sar.c
+++ b/src/vendorcode/google/chromeos/sar.c
@@ -118,6 +118,14 @@ static size_t bpag_table_size(const struct bpag_profile *bpag)
 	return sizeof(struct bpag_profile);
 }
 
+static size_t bbfb_table_size(const struct bbfb_profile *bbfb)
+{
+	if (bbfb == NULL)
+		return 0;
+
+	return sizeof(struct bbfb_profile);
+}
+
 static bool valid_legacy_length(size_t bin_len)
 {
 	if (bin_len == LEGACY_SAR_WGDS_BIN_SIZE)
@@ -172,6 +180,7 @@ static int fill_wifi_sar_limits(union wifi_sar_limits *sar_limits, const uint8_t
 	expected_sar_bin_size += bsar_table_size(sar_limits->bsar);
 	expected_sar_bin_size += wbem_table_size(sar_limits->wbem);
 	expected_sar_bin_size += bpag_table_size(sar_limits->bpag);
+	expected_sar_bin_size += bbfb_table_size(sar_limits->bbfb);
 
 	if (sar_bin_size != expected_sar_bin_size) {
 		printk(BIOS_ERR, "Invalid SAR size, expected: %zu, obtained: %zu\n",