dm: x86: Add a driver for Intel PCH9

At some point we may need to distinguish between different types of PCHs,
but for existing supported platforms we only need to worry about version 7
and version 9 bridges. Add a driver for the PCH9.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

drivers/pch/Makefile

@@ -4,3 +4,4 @@
 
 obj-y += pch-uclass.o
 obj-y += pch7.o
+obj-y += pch9.o

drivers/pch/pch9.c

@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2014 Google, Inc
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <pch.h>
+
+#define SBASE_ADDR	0x54
+
+static int pch9_get_sbase(struct udevice *dev, ulong *sbasep)
+{
+	uint32_t sbase_addr;
+
+	dm_pci_read_config32(dev, SBASE_ADDR, &sbase_addr);
+	*sbasep = sbase_addr & 0xfffffe00;
+
+	return 0;
+}
+
+static enum pch_version pch9_get_version(struct udevice *dev)
+{
+	return PCHV_9;
+}
+
+static const struct pch_ops pch9_ops = {
+	.get_sbase	= pch9_get_sbase,
+	.get_version	= pch9_get_version,
+};
+
+static const struct udevice_id pch9_ids[] = {
+	{ .compatible = "intel,pch9" },
+	{ }
+};
+
+U_BOOT_DRIVER(pch9_drv) = {
+	.name		= "intel-pch9",
+	.id		= UCLASS_PCH,
+	.of_match	= pch9_ids,
+	.ops		= &pch9_ops,
+};