mb/google/brya/variants/brask: Enable Bluetooth offload support

Add fw_config NAU88L25B_I2S field, I2S2 configuration and
enabling CnviBtAudioOffload UPD bit.

BUG=none
TEST=temerge-brask coreboot

Signed-off-by: Mac Chiang <mac.chiang@intel.com>
Change-Id: Id5da8c5c471be176bc0fe1eda4da7faf8ed2e8d2
Reviewed-on: https://review.coreboot.org/c/coreboot/+/61404
Reviewed-by: Zhuohao Lee <zhuohao@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/google/brya/variants/brask/Makefile.inc

@@ -5,3 +5,6 @@ romstage-y += gpio.c
 
 ramstage-y += gpio.c
 ramstage-y += ramstage.c
+
+ramstage-$(CONFIG_FW_CONFIG) += fw_config.c
+ramstage-$(CONFIG_FW_CONFIG) += variant.c

src/mainboard/google/brya/variants/brask/fw_config.c

@@ -0,0 +1,44 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <bootstate.h>
+#include <console/console.h>
+#include <fw_config.h>
+#include <gpio.h>
+
+static const struct pad_config bt_i2s_enable_pads[] = {
+	PAD_CFG_NF(GPP_VGPIO_30, NONE, DEEP, NF3),	/* BT_I2S_BCLK */
+	PAD_CFG_NF(GPP_VGPIO_31, NONE, DEEP, NF3),	/* BT_I2S_SYNC */
+	PAD_CFG_NF(GPP_VGPIO_32, NONE, DEEP, NF3),	/* BT_I2S_SDO */
+	PAD_CFG_NF(GPP_VGPIO_33, NONE, DEEP, NF3),	/* BT_I2S_SDI */
+	PAD_CFG_NF(GPP_VGPIO_34, NONE, DEEP, NF1),	/* SSP2_SCLK */
+	PAD_CFG_NF(GPP_VGPIO_35, NONE, DEEP, NF1),	/* SSP2_SFRM */
+	PAD_CFG_NF(GPP_VGPIO_36, NONE, DEEP, NF1),	/* SSP_TXD */
+	PAD_CFG_NF(GPP_VGPIO_37, NONE, DEEP, NF1),	/* SSP_RXD */
+};
+
+static const struct pad_config bt_i2s_disable_pads[] = {
+	PAD_NC(GPP_VGPIO_30, NONE),
+	PAD_NC(GPP_VGPIO_31, NONE),
+	PAD_NC(GPP_VGPIO_32, NONE),
+	PAD_NC(GPP_VGPIO_33, NONE),
+	PAD_NC(GPP_VGPIO_34, NONE),
+	PAD_NC(GPP_VGPIO_35, NONE),
+	PAD_NC(GPP_VGPIO_36, NONE),
+	PAD_NC(GPP_VGPIO_37, NONE),
+};
+
+static void fw_config_handle(void *unused)
+{
+	if (!fw_config_is_provisioned() || fw_config_probe(FW_CONFIG(AUDIO, AUDIO_UNKNOWN))) {
+		printk(BIOS_INFO, "Disable BT offload audio related GPIO pins.\n");
+		gpio_configure_pads(bt_i2s_disable_pads, ARRAY_SIZE(bt_i2s_disable_pads));
+		return;
+	}
+
+	if (fw_config_probe(FW_CONFIG(AUDIO, NAU88L25B_I2S))) {
+		printk(BIOS_INFO, "BT offload enabled over I2S with NAU88L25B\n");
+		gpio_configure_pads(bt_i2s_enable_pads, ARRAY_SIZE(bt_i2s_enable_pads));
+	}
+
+}
+BOOT_STATE_INIT_ENTRY(BS_DEV_ENABLE, BS_ON_ENTRY, fw_config_handle, NULL);

src/mainboard/google/brya/variants/brask/overridetree.cb

@@ -1,3 +1,10 @@
+fw_config
+	field AUDIO 0 2
+		option AUDIO_UNKNOWN	0
+		option NAU88L25B_I2S	1
+	end
+end
+
 chip soc/intel/alderlake
 	device domain 0 on
 		device ref dtt on

src/mainboard/google/brya/variants/brask/variant.c

@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <chip.h>
+#include <fw_config.h>
+#include <baseboard/variants.h>
+
+void variant_update_soc_chip_config(struct soc_intel_alderlake_config *config)
+{
+	config->CnviBtAudioOffload = fw_config_probe(FW_CONFIG(AUDIO, NAU88L25B_I2S));
+}