soc/intel/apollolake: handle p2sb quirks

The P2SB device is device 0xd and function 0. If hidden that
causes the latter pci devices on function >= 1 to not be probed
in the kernel.  This is also a problem for coreboot if the P2SB
device is hidden by FSP. That means the coreboot driver won't
be ran. Therefore, provide hide and unhide functions for the
P2SB device.

The other quirk is to allow the GPIO devices to work correctly.
Those devices are ACPI devices. However, their resources are
sub-regions within the P2SB BAR. Sadly, linux doesn't handle
ACPI devices being children of PCI devices. This leads to resource
conflict errors when the P2SB device is visible. For the
time being keep the P2SB device hidden, but also ensure the
resources it is using are accounted for and reserved. The fallout
of that is the PMC and SPI device are no longer probed by the
kernel.

BUG=chrome-os-partner:53017
TEST=Ensured P2SB device is visible and pci resources are allocated
     correctly for the devices.

Change-Id: I24e59bbde74310e1ce8425b344a3ad0b88702153
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/15530
Tested-by: build bot (Jenkins)
Reviewed-by: Andrey Petrov <andrey.petrov@intel.com>
Reviewed-by: Furquan Shaikh <furquan@google.com>

1 files changed, 74 insertions, 0 deletions

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,
+};