intel/fsp_baytrail: Fix LPE initialization and enable ACPI mode

This change properly assigns resources to the LPE (Low Power Engine for
Audio) and enables ACPI mode.
lpe.c was copied from intel/baytrail with a few minor adjustment for the
different config structure.

ACPI mode requires setting LpeAcpiModeEnable=LPE_ACPI_MODE_ENABLED and
applying the patch that disables clearing gnvs.
https://review.coreboot.org/#/c/14040/

Change-Id: I3fff9aa158bde88e571082642d4f985a5ae1976e
Signed-off-by: Ben Gardner <gardner.ben@gmail.com>
Reviewed-on: https://review.coreboot.org/14041
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>

3 files changed, 190 insertions, 0 deletions

diff --git a/src/soc/intel/fsp_baytrail/Makefile.inc b/src/soc/intel/fsp_baytrail/Makefile.inc
index 41672e6abf..65eb55f0b7 100644
--- a/src/soc/intel/fsp_baytrail/Makefile.inc
+++ b/src/soc/intel/fsp_baytrail/Makefile.inc
@@ -49,6 +49,7 @@ romstage-y += reset.c
 ramstage-y += reset.c
 ramstage-y += cpu.c
 ramstage-y += acpi.c
+ramstage-y += lpe.c
 smm-$(CONFIG_HAVE_SMI_HANDLER) += pmutil.c
 smm-$(CONFIG_HAVE_SMI_HANDLER) += smihandler.c
 ramstage-$(CONFIG_HAVE_SMI_HANDLER) += smm.c
diff --git a/src/soc/intel/fsp_baytrail/chip.h b/src/soc/intel/fsp_baytrail/chip.h
index 35dafa9af1..156a08434c 100644
--- a/src/soc/intel/fsp_baytrail/chip.h
+++ b/src/soc/intel/fsp_baytrail/chip.h
@@ -342,6 +342,10 @@ struct soc_intel_fsp_baytrail_config {
 	uint8_t  DIMMtFAW;
 	#define  DIMM_TFAW_DEFAULT	UPD_DEFAULT
 
+	/* LPE Audio Clock configuration. */
+	int lpe_codec_clk_freq; /* 19 or 25 are valid. */
+	int lpe_codec_clk_num; /* Platform clock pins. [0:5] are valid. */
+
 /* ***** ACPI configuration ***** */
 	/* Options for these are in src/arch/x86/include/arch/acpi.h */
 	uint8_t  fadt_pm_profile;
diff --git a/src/soc/intel/fsp_baytrail/lpe.c b/src/soc/intel/fsp_baytrail/lpe.c
new file mode 100644
index 0000000000..4fbdce15a4
--- /dev/null
+++ b/src/soc/intel/fsp_baytrail/lpe.c
@@ -0,0 +1,185 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2013 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 <arch/io.h>
+#include <cbmem.h>
+#include <console/console.h>
+#include <device/device.h>
+#include <device/pci.h>
+#include <device/pci_ids.h>
+#include <reg_script.h>
+
+#include <soc/iomap.h>
+#include <soc/iosf.h>
+#include <soc/lpc.h>
+#include <soc/nvs.h>
+#include <soc/pattrs.h>
+#include <soc/pci_devs.h>
+#include <soc/pmc.h>
+#include <soc/ramstage.h>
+#include "chip.h"
+
+
+/* The LPE audio devices needs 1MiB of memory reserved aligned to a 512MiB
+ * address. Just take 1MiB @ 512MiB. */
+#define FIRMWARE_PHYS_BASE (512 << 20)
+#define FIRMWARE_PHYS_LENGTH (1 << 20)
+#define FIRMWARE_PCI_REG_BASE 0xa8
+#define FIRMWARE_PCI_REG_LENGTH 0xac
+#define FIRMWARE_REG_BASE_C0 0x144000
+#define FIRMWARE_REG_LENGTH_C0 (FIRMWARE_REG_BASE_C0 + 4)
+
+static void assign_device_nvs(device_t dev, u32 *field, unsigned index)
+{
+	struct resource *res;
+
+	res = find_resource(dev, index);
+	if (res)
+		*field = res->base;
+}
+
+static void lpe_enable_acpi_mode(device_t dev)
+{
+	static const struct reg_script ops[] = {
+		/* Disable PCI interrupt, enable Memory and Bus Master */
+		REG_PCI_OR32(PCI_COMMAND,
+			     PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER | (1<<10)),
+		/* Enable ACPI mode */
+		REG_IOSF_OR(IOSF_PORT_0x58, LPE_PCICFGCTR1,
+			    LPE_PCICFGCTR1_PCI_CFG_DIS |
+			    LPE_PCICFGCTR1_ACPI_INT_EN),
+		REG_SCRIPT_END
+	};
+	global_nvs_t *gnvs;
+
+	/* Find ACPI NVS to update BARs */
+	gnvs = (global_nvs_t *)cbmem_find(CBMEM_ID_ACPI_GNVS);
+	if (!gnvs) {
+		printk(BIOS_ERR, "Unable to locate Global NVS\n");
+		return;
+	}
+
+	/* Save BAR0, BAR1, and firmware base  to ACPI NVS */
+	assign_device_nvs(dev, &gnvs->dev.lpe_bar0, PCI_BASE_ADDRESS_0);
+	assign_device_nvs(dev, &gnvs->dev.lpe_bar1, PCI_BASE_ADDRESS_1);
+	assign_device_nvs(dev, &gnvs->dev.lpe_fw, FIRMWARE_PCI_REG_BASE);
+
+	/* Device is enabled in ACPI mode */
+	gnvs->dev.lpe_en = 1;
+
+	/* Put device in ACPI mode */
+	reg_script_run_on_dev(dev, ops);
+}
+
+static void setup_codec_clock(device_t dev)
+{
+	uint32_t reg;
+	u32 *clk_reg;
+	struct soc_intel_fsp_baytrail_config *config;
+	const char *freq_str;
+
+	config = dev->chip_info;
+	switch (config->lpe_codec_clk_freq) {
+	case 19:
+		freq_str = "19.2";
+		reg = CLK_FREQ_19P2MHZ;
+		break;
+	case 25:
+		freq_str = "25";
+		reg = CLK_FREQ_25MHZ;
+		break;
+	default:
+		printk(BIOS_DEBUG, "LPE codec clock not required.\n");
+		return;
+	}
+
+	/* Default to always running. */
+	reg |= CLK_CTL_ON;
+
+	if (config->lpe_codec_clk_num < 0 || config->lpe_codec_clk_num > 5) {
+		printk(BIOS_DEBUG, "Invalid LPE codec clock number.\n");
+		return;
+	}
+
+	printk(BIOS_DEBUG, "LPE Audio codec clock set to %sMHz.\n", freq_str);
+
+	clk_reg = (u32 *)(PMC_BASE_ADDRESS + PLT_CLK_CTL_0);
+	clk_reg += config->lpe_codec_clk_num;
+
+	write32(clk_reg, (read32(clk_reg) & ~0x7) | reg);
+}
+
+static void lpe_stash_firmware_info(device_t dev)
+{
+	struct resource *res;
+	struct resource *mmio;
+	const struct pattrs *pattrs = pattrs_get();
+
+	res = find_resource(dev, FIRMWARE_PCI_REG_BASE);
+	if (res == NULL) {
+		printk(BIOS_DEBUG, "LPE Firmware memory not found.\n");
+		return;
+	}
+
+	/* Continue using old way of informing firmware address / size. */
+	pci_write_config32(dev, FIRMWARE_PCI_REG_BASE, res->base);
+	pci_write_config32(dev, FIRMWARE_PCI_REG_LENGTH, res->size);
+
+	/* C0 and later steppings use an offset in the MMIO space. */
+	if (pattrs->stepping >= STEP_C0) {
+		mmio = find_resource(dev, PCI_BASE_ADDRESS_0);
+		write32((u32 *)(uintptr_t)(mmio->base + FIRMWARE_REG_BASE_C0),
+			res->base);
+		write32((u32 *)(uintptr_t)(mmio->base + FIRMWARE_REG_LENGTH_C0),
+			res->size);
+	}
+}
+
+static void lpe_init(device_t dev)
+{
+	struct soc_intel_fsp_baytrail_config *config = dev->chip_info;
+
+	lpe_stash_firmware_info(dev);
+
+	setup_codec_clock(dev);
+
+	if (config->LpeAcpiModeEnable == LPE_ACPI_MODE_ENABLED)
+		lpe_enable_acpi_mode(dev);
+}
+
+static void lpe_read_resources(device_t dev)
+{
+	pci_dev_read_resources(dev);
+
+	reserved_ram_resource(dev, FIRMWARE_PCI_REG_BASE,
+			      FIRMWARE_PHYS_BASE >> 10,
+			      FIRMWARE_PHYS_LENGTH >> 10);
+}
+
+static const struct device_operations device_ops = {
+	.read_resources		= lpe_read_resources,
+	.set_resources		= pci_dev_set_resources,
+	.enable_resources	= pci_dev_enable_resources,
+	.init			= lpe_init,
+	.enable			= NULL,
+	.scan_bus		= NULL,
+	.ops_pci		= &soc_pci_ops,
+};
+
+static const struct pci_driver southcluster __pci_driver = {
+	.ops		= &device_ops,
+	.vendor		= PCI_VENDOR_ID_INTEL,
+	.device		= LPE_DEVID,
+};