mainboard/google/poppy: Provide nhlt variant API

Move current NHLT configuration implementation to baseboard so that
variants can leverage it or provide their own configuration.

BUG=b:37375693

Change-Id: I2a4317c112f9e3614bd01eb6809727b73328d29d
Signed-off-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: https://review.coreboot.org/19326
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/mainboard/google/poppy/mainboard.c

@@ -14,15 +14,12 @@
  */
 
 #include <arch/acpi.h>
-#include <console/console.h>
+#include <baseboard/variants.h>
 #include <device/device.h>
 #include <ec/ec.h>
 #include <soc/nhlt.h>
 #include <vendorcode/google/chromeos/chromeos.h>
 
-static const char *oem_id_maxim = "GOOGLE";
-static const char *oem_table_id_maxim = "POPPYMAX";
-
 static void mainboard_init(device_t dev)
 {
 	mainboard_ec_init();
@@ -34,6 +31,9 @@ static unsigned long mainboard_write_acpi_tables(device_t device,
 	uintptr_t start_addr;
 	uintptr_t end_addr;
 	struct nhlt *nhlt;
+	const char *oem_id = NULL;
+	const char *oem_table_id = NULL;
+	uint32_t oem_revision = 0;
 
 	start_addr = current;
 
@@ -42,24 +42,11 @@ static unsigned long mainboard_write_acpi_tables(device_t device,
 	if (nhlt == NULL)
 		return start_addr;
 
-	/* 2 Channel DMIC array. */
+	variant_nhlt_init(nhlt);
-	if (nhlt_soc_add_dmic_array(nhlt, 2))
+	variant_nhlt_oem_overrides(&oem_id, &oem_table_id, &oem_revision);
-		printk(BIOS_ERR, "Couldn't add 2CH DMIC array.\n");
-
-	/* 4 Channel DMIC array. */
-	if (nhlt_soc_add_dmic_array(nhlt, 4))
-		printk(BIOS_ERR, "Couldn't add 4CH DMIC arrays.\n");
-
-	/* Maxim MAX98927 Smart Amps for left and right channel */
-	if (nhlt_soc_add_max98927(nhlt, AUDIO_LINK_SSP0))
-		printk(BIOS_ERR, "Couldn't add Maxim MAX98927\n");
-
-	/* Realtek RT5663 Headset codec. */
-	if (nhlt_soc_add_rt5663(nhlt, AUDIO_LINK_SSP1))
-		printk(BIOS_ERR, "Couldn't add Realtek RT5663.\n");
 
 	end_addr = nhlt_soc_serialize_oem_overrides(nhlt, start_addr,
-			oem_id_maxim, oem_table_id_maxim, 0);
+			oem_id, oem_table_id, oem_revision);
 
 	if (end_addr != start_addr)
 		acpi_add_table(rsdp, (void *)start_addr);

src/mainboard/google/poppy/variants/baseboard/Makefile.inc

@@ -5,3 +5,4 @@ romstage-y += memory.c
 
 ramstage-y += boardid.c
 ramstage-y += gpio.c
+ramstage-y += nhlt.c

src/mainboard/google/poppy/variants/baseboard/include/baseboard/variants.h

@@ -46,4 +46,9 @@ struct memory_params {
 void variant_memory_params(struct memory_params *p);
 int variant_memory_sku(void);
 
+struct nhlt;
+void variant_nhlt_init(struct nhlt *nhlt);
+void variant_nhlt_oem_overrides(const char **oem_id, const char **oem_table_id,
+				uint32_t *oem_revision);
+
 #endif /* __BASEBOARD_VARIANTS_H__ */

src/mainboard/google/poppy/variants/baseboard/nhlt.c

@@ -0,0 +1,47 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2017 Google Inc.
+ *
+ * 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 <baseboard/variants.h>
+#include <console/console.h>
+#include <nhlt.h>
+#include <soc/nhlt.h>
+
+void __attribute__((weak)) variant_nhlt_init(struct nhlt *nhlt)
+{
+	/* 2 Channel DMIC array. */
+	if (nhlt_soc_add_dmic_array(nhlt, 2))
+		printk(BIOS_ERR, "Couldn't add 2CH DMIC array.\n");
+
+	/* 4 Channel DMIC array. */
+	if (nhlt_soc_add_dmic_array(nhlt, 4))
+		printk(BIOS_ERR, "Couldn't add 4CH DMIC arrays.\n");
+
+	/* Maxim MAX98927 Smart Amps for left and right channel */
+	if (nhlt_soc_add_max98927(nhlt, AUDIO_LINK_SSP0))
+		printk(BIOS_ERR, "Couldn't add Maxim MAX98927\n");
+
+	/* Realtek RT5663 Headset codec. */
+	if (nhlt_soc_add_rt5663(nhlt, AUDIO_LINK_SSP1))
+		printk(BIOS_ERR, "Couldn't add Realtek RT5663.\n");
+}
+
+void __attribute__((weak)) variant_nhlt_oem_overrides(const char **oem_id,
+						const char **oem_table_id,
+						uint32_t *oem_revision)
+{
+	*oem_id = "GOOGLE";
+	*oem_table_id = "POPPYMAX";
+	*oem_revision = 0;
+}