soc/intel/tigerlake: Provide SoundWire controller properties

The Intel Tigerlake SoundWire controller has 4 master links which
are configured differently depending on the external crystal oscillator
which is connected to the PCH.

This function will read the PCH PMC EPOC register to determine the
frequency and then fill out the master link entries with the correct
table values.

The frequency is also provided directly in a custom "ip-clock" property
which will be added to the link descriptor and passed to the OS driver
so it can know the clock rate of the master.

BUG=b:146482091

Signed-off-by: Duncan Laurie <dlaurie@google.com>
Change-Id: I98b7df21210c29cd8defeff648f2c2207d629295
Reviewed-on: https://review.coreboot.org/c/coreboot/+/40889
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>

src/soc/intel/tigerlake/Makefile.inc

@@ -42,6 +42,7 @@ ramstage-y += p2sb.c
 ramstage-y += pmc.c
 ramstage-y += reset.c
 ramstage-y += smmrelocate.c
+ramstage-y += soundwire.c
 ramstage-y += systemagent.c
 ramstage-y += me.c
 

src/soc/intel/tigerlake/soundwire.c

@@ -0,0 +1,71 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <acpi/acpi_soundwire.h>
+#include <console/console.h>
+#include <device/mmio.h>
+#include <device/soundwire.h>
+#include <drivers/intel/soundwire/soundwire.h>
+#include <intelblocks/pmclib.h>
+#include <soc/pmc.h>
+#include <string.h>
+
+static const struct soundwire_link link_xtal_38_4 = {
+	.clock_stop_mode0_supported = 1,
+	.clock_stop_mode1_supported = 1,
+	.clock_frequencies_supported_count = 1,
+	.clock_frequencies_supported = { 4800 * KHz },
+	.default_frame_rate = 48 * KHz,
+	.default_frame_row_size = 50,
+	.default_frame_col_size = 4,
+	.dynamic_frame_shape = 1,
+	.command_error_threshold = 16,
+};
+
+static const struct soundwire_link link_xtal_24 = {
+	.clock_stop_mode0_supported = 1,
+	.clock_stop_mode1_supported = 1,
+	.clock_frequencies_supported_count = 1,
+	.clock_frequencies_supported = { 6 * MHz },
+	.default_frame_rate = 48 * KHz,
+	.default_frame_row_size = 125,
+	.default_frame_col_size = 2,
+	.dynamic_frame_shape = 1,
+	.command_error_threshold = 16,
+};
+
+static struct intel_soundwire_controller intel_controller = {
+	.acpi_address = 0x40000000,
+	.sdw = {
+		.master_list_count = 4
+	}
+};
+
+int soc_fill_soundwire_controller(struct intel_soundwire_controller **controller)
+{
+	const struct soundwire_link *link;
+	enum pch_pmc_xtal xtal = pmc_get_xtal_freq();
+	size_t i;
+
+	/* Select link config based on XTAL frequency and set IP clock. */
+	switch (xtal) {
+	case XTAL_24_MHZ:
+		link = &link_xtal_24;
+		intel_controller.ip_clock = 24 * MHz;
+		break;
+	case XTAL_38_4_MHZ:
+		link = &link_xtal_38_4;
+		intel_controller.ip_clock = 38400 * KHz;
+		break;
+	case XTAL_19_2_MHZ:
+	default:
+		printk(BIOS_ERR, "%s: XTAL not supported: 0x%x\n", __func__, xtal);
+		return -1;
+	}
+
+	/* Fill link config in controller map based on selected XTAL. */
+	for (i = 0; i < intel_controller.sdw.master_list_count; i++)
+		memcpy(&intel_controller.sdw.master_list[i], link, sizeof(*link));
+
+	*controller = &intel_controller;
+	return 0;
+}