5 files changed, 114 insertions, 1 deletions
diff --git a/src/soc/intel/apollolake/Makefile.inc b/src/soc/intel/apollolake/Makefile.inc
index a64ee78328..9fbb82d975 100644
--- a/src/soc/intel/apollolake/Makefile.inc
+++ b/src/soc/intel/apollolake/Makefile.inc
@@ -52,6 +52,7 @@ ramstage-y += lpc.c
 ramstage-y += lpc_lib.c
 ramstage-y += memmap.c
 ramstage-y += mmap_boot.c
+ramstage-y += p2sb.c
 ramstage-y += uart.c
 ramstage-y += nhlt.c
 ramstage-y += northbridge.c
diff --git a/src/soc/intel/apollolake/chip.c b/src/soc/intel/apollolake/chip.c
index 68459e602a..00470a201a 100644
--- a/src/soc/intel/apollolake/chip.c
+++ b/src/soc/intel/apollolake/chip.c
@@ -33,6 +33,7 @@
 #include <soc/pci_devs.h>
 #include <spi-generic.h>
 #include <soc/pm.h>
+#include <soc/p2sb.h>
 
 #include "chip.h"
 
@@ -153,6 +154,14 @@ static void soc_init(void *data)
 	range_entry_init(&range, 0x200000, 4ULL*GiB, 0);
 	fsp_silicon_init(&range);
 
+	/*
+	 * Keep the P2SB device visible so it and the other devices are
+	 * visible in coreboot for driver support and PCI resource allocation.
+	 * There is a UPD setting for this, but it's more consistent to use
+	 * hide and unhide symmetrically.
+	 */
+	p2sb_unhide();
+
 	/* Allocate ACPI NVS in CBMEM */
 	gnvs = cbmem_add(CBMEM_ID_ACPI_GNVS, sizeof(*gnvs));
 }
@@ -346,8 +355,11 @@ static void fsp_notify_dummy(void *arg)
 			fsp_handle_reset(ret);
 	}
 	/* Call END_OF_FIRMWARE Notify after READY_TO_BOOT Notify */
-	if (ph == READY_TO_BOOT)
+	if (ph == READY_TO_BOOT) {
 		fsp_notify_dummy((void *)END_OF_FIRMWARE);
+		/* Hide the P2SB device to align with previous behavior. */
+		p2sb_hide();
+	}
 }
 
 BOOT_STATE_INIT_ENTRY(BS_DEV_RESOURCES, BS_ON_EXIT, fsp_notify_dummy,
diff --git a/src/soc/intel/apollolake/include/soc/iomap.h b/src/soc/intel/apollolake/include/soc/iomap.h
index e9caecac7a..2045434e6e 100644
--- a/src/soc/intel/apollolake/include/soc/iomap.h
+++ b/src/soc/intel/apollolake/include/soc/iomap.h
@@ -18,7 +18,10 @@
 #ifndef _SOC_APOLLOLAKE_IOMAP_H_
 #define _SOC_APOLLOLAKE_IOMAP_H_
 
+#include <commonlib/helpers.h>
+
 #define P2SB_BAR			CONFIG_IOSF_BASE_ADDRESS
+#define P2SB_SIZE			(16 * MiB)
 #define MCH_BASE_ADDR			0xfed10000
 #define MCH_BASE_SIZE			(32 * KiB)
 
diff --git a/src/soc/intel/apollolake/include/soc/p2sb.h b/src/soc/intel/apollolake/include/soc/p2sb.h
new file mode 100644
index 0000000000..a0bcc67f45
--- /dev/null
+++ b/src/soc/intel/apollolake/include/soc/p2sb.h
@@ -0,0 +1,23 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2016 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ */
+
+#ifndef _SOC_APOLLOLAKE_P2SB_H_
+#define _SOC_APOLLOLAKE_P2SB_H_
+
+void p2sb_unhide(void);
+void p2sb_hide(void);
+
+#endif /* _SOC_APOLLOLAKE_P2SB_H_ */
diff --git a/src/soc/intel/apollolake/p2sb.c b/src/soc/intel/apollolake/p2sb.c
new file mode 100644
index 0000000000..7834e3866e
--- /dev/null
+++ b/src/soc/intel/apollolake/p2sb.c
@@ -0,0 +1,74 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2016 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 <console/console.h>
+#include <device/device.h>
+#include <device/pci.h>
+#include <device/pci_ids.h>
+#include <rules.h>
+#include <soc/iomap.h>
+#include <soc/pci_devs.h>
+#include <soc/pci_ids.h>
+#include <soc/p2sb.h>
+
+#define P2SB_E0 0xe0
+#define HIDE_BIT (1 << 0)
+
+static void p2sb_set_hide_bit(int hide)
+{
+	struct device *dev;
+	const uint16_t reg = P2SB_E0 + 1;
+	const uint8_t mask = HIDE_BIT;
+	uint8_t val;
+
+	dev = P2SB_DEV;
+
+	val = pci_read_config8(dev, reg);
+	val &= ~mask;
+	if (hide)
+		val |= mask;
+	pci_write_config8(dev, reg, val);
+}
+
+void p2sb_unhide(void)
+{
+	p2sb_set_hide_bit(0);
+}
+
+void p2sb_hide(void)
+{
+	p2sb_set_hide_bit(HIDE_BIT);
+}
+
+static void read_resources(struct device *dev)
+{
+	/*
+	 * There's only one resource on the P2SB device. It's also already
+	 * manually set to a fixed address in earlier boot stages.
+	 */
+	mmio_resource(dev, PCI_BASE_ADDRESS_0, P2SB_BAR / KiB, P2SB_SIZE / KiB);
+}
+
+static const struct device_operations device_ops = {
+	.read_resources		= read_resources,
+	.set_resources		= DEVICE_NOOP,
+};
+
+static const struct pci_driver pmc __pci_driver = {
+	.ops	= &device_ops,
+	.vendor	= PCI_VENDOR_ID_INTEL,
+	.device	= PCI_DEVICE_ID_APOLLOLAKE_P2SB,
+};