dm: Expand the uclass for Platform Controller Hubs (PCH)

A Platform Controller Hub is an Intel concept - it is like the peripherals
on an SoC and is often in a separate chip from the CPU. The chip is typically
found on the first PCI bus and integrates multiple devices.

We have a very simple uclass to support PCHs. Add a few operations, such as
setting up the devices on the PCH and finding the SPI controller base
address. Also move it into drivers/pch/ since we will be adding a few PCH
drivers.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index cd5ecb6..43792bc 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -24,7 +24,6 @@
 ifndef CONFIG_DM_PCI
 obj-$(CONFIG_PCI) += pci_type1.o
 endif
-obj-y	+= pch-uclass.o
 obj-y	+= pirq_routing.o
 obj-y	+= relocate.o
 obj-y += physmem.o
diff --git a/arch/x86/lib/pch-uclass.c b/arch/x86/lib/pch-uclass.c
deleted file mode 100644
index 20dfa81..0000000
--- a/arch/x86/lib/pch-uclass.c
+++ /dev/null
@@ -1,30 +0,0 @@
-/*
- * Copyright (c) 2015 Google, Inc
- * Written by Simon Glass <sjg@chromium.org>
- *
- * SPDX-License-Identifier:	GPL-2.0+
- */
-
-#include <common.h>
-#include <dm.h>
-#include <dm/root.h>
-
-DECLARE_GLOBAL_DATA_PTR;
-
-static int pch_uclass_post_bind(struct udevice *bus)
-{
-	/*
-	 * Scan the device tree for devices
-	 *
-	 * Before relocation, only bind devices marked for pre-relocation
-	 * use.
-	 */
-	return dm_scan_fdt_node(bus, gd->fdt_blob, bus->of_offset,
-				gd->flags & GD_FLG_RELOC ? false : true);
-}
-
-UCLASS_DRIVER(pch) = {
-	.id		= UCLASS_PCH,
-	.name		= "pch",
-	.post_bind	= pch_uclass_post_bind,
-};
diff --git a/drivers/Makefile b/drivers/Makefile
index 00da40b..6294048 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -51,6 +51,7 @@
 obj-y += misc/
 obj-y += pcmcia/
 obj-y += dfu/
+obj-$(CONFIG_X86) += pch/
 obj-y += rtc/
 obj-y += sound/
 obj-y += timer/
diff --git a/drivers/pch/Makefile b/drivers/pch/Makefile
new file mode 100644
index 0000000..d69a99c
--- /dev/null
+++ b/drivers/pch/Makefile
@@ -0,0 +1,5 @@
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+obj-y += pch-uclass.o
diff --git a/drivers/pch/pch-uclass.c b/drivers/pch/pch-uclass.c
new file mode 100644
index 0000000..4579ed1
--- /dev/null
+++ b/drivers/pch/pch-uclass.c
@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2015 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <pch.h>
+#include <dm/root.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int pch_get_sbase(struct udevice *dev, ulong *sbasep)
+{
+	struct pch_ops *ops = pch_get_ops(dev);
+
+	*sbasep = 0;
+	if (!ops->get_sbase)
+		return -ENOSYS;
+
+	return ops->get_sbase(dev, sbasep);
+}
+
+enum pch_version pch_get_version(struct udevice *dev)
+{
+	struct pch_ops *ops = pch_get_ops(dev);
+
+	if (!ops->get_version)
+		return -ENOSYS;
+
+	return ops->get_version(dev);
+}
+
+int pch_set_spi_protect(struct udevice *dev, bool protect)
+{
+	struct pch_ops *ops = pch_get_ops(dev);
+
+	if (!ops->set_spi_protect)
+		return -ENOSYS;
+
+	return ops->set_spi_protect(dev, protect);
+}
+
+static int pch_uclass_post_bind(struct udevice *bus)
+{
+	/*
+	 * Scan the device tree for devices
+	 *
+	 * Before relocation, only bind devices marked for pre-relocation
+	 * use.
+	 */
+	return dm_scan_fdt_node(bus, gd->fdt_blob, bus->of_offset,
+				gd->flags & GD_FLG_RELOC ? false : true);
+}
+
+UCLASS_DRIVER(pch) = {
+	.id		= UCLASS_PCH,
+	.name		= "pch",
+	.post_bind	= pch_uclass_post_bind,
+};
diff --git a/include/pch.h b/include/pch.h
new file mode 100644
index 0000000..ff26865
--- /dev/null
+++ b/include/pch.h
@@ -0,0 +1,74 @@
+/*
+ * Copyright (c) 2015 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __pch_h
+#define __pch_h
+
+enum pch_version {
+	PCHV_UNKNOWN,
+	PCHV_7,
+	PCHV_9,
+};
+
+/* Operations for the Platform Controller Hub */
+struct pch_ops {
+	/**
+	 * get_sbase() - get the address of SPI base
+	 *
+	 * @dev:	PCH device to check
+	 * @sbasep:	Returns address of SPI base if available, else 0
+	 * @return 0 if OK, -ve on error (e.g. there is no SPI base)
+	 */
+	int (*get_sbase)(struct udevice *dev, ulong *sbasep);
+
+	/**
+	 * get_version() - get the PCH version
+	 *
+	 * @return version, or -ENOSYS if unknown
+	 */
+	enum pch_version (*get_version)(struct udevice *dev);
+
+	/**
+	 * set_spi_protect() - set whether SPI flash is protected or not
+	 *
+	 * @dev:	PCH device to adjust
+	 * @protect:	true to protect, false to unprotect
+	 *
+	 * @return 0 on success, -ENOSYS if not implemented
+	 */
+	int (*set_spi_protect)(struct udevice *dev, bool protect);
+};
+
+#define pch_get_ops(dev)        ((struct pch_ops *)(dev)->driver->ops)
+
+/**
+ * pch_get_sbase() - get the address of SPI base
+ *
+ * @dev:	PCH device to check
+ * @sbasep:	Returns address of SPI base if available, else 0
+ * @return 0 if OK, -ve on error (e.g. there is no SPI base)
+ */
+int pch_get_sbase(struct udevice *dev, ulong *sbasep);
+
+/**
+ * pch_get_version() - get the PCH version
+ *
+ * @return version, or -ENOSYS if unknown
+ */
+enum pch_version pch_get_version(struct udevice *dev);
+
+/**
+ * set_spi_protect() - set whether SPI flash is protected or not
+ *
+ * @dev:	PCH device to adjust
+ * @protect:	true to protect, false to unprotect
+ *
+ * @return 0 on success, -ENOSYS if not implemented
+ */
+int pch_set_spi_protect(struct udevice *dev, bool protect);
+
+#endif