x86: Move UCLASS_IRQ into a separate file

Update this uclass to support the needs of the Apollo Lake ITSS. It
supports four operations.

Move the uclass into a separate directory so that sandbox can use it too.
Add a new Kconfig to control it and enable this on x86.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/arch/Kconfig b/arch/Kconfig
index e1f1fcd..6865e1f 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -186,6 +186,7 @@
 	imply USB_HOST_ETHER
 	imply PCH
 	imply RTC_MC146818
+	imply IRQ
 
 	# Thing to enable for when SPL/TPL are enabled: SPL
 	imply SPL_DM
diff --git a/arch/x86/cpu/irq.c b/arch/x86/cpu/irq.c
index 3adc155..cb18349 100644
--- a/arch/x86/cpu/irq.c
+++ b/arch/x86/cpu/irq.c
@@ -370,8 +370,3 @@
 	.probe		= irq_router_probe,
 	.priv_auto_alloc_size = sizeof(struct irq_router),
 };
-
-UCLASS_DRIVER(irq) = {
-	.id		= UCLASS_IRQ,
-	.name		= "irq",
-};
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 71643af..f18aa8f 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -203,6 +203,15 @@
 	  Security Monitor can be transitioned on any security failures,
 	  like software violations or hardware security violations.
 
+config IRQ
+	bool "Intel Interrupt controller"
+	depends on X86 || SANDBOX
+	help
+	  This enables support for Intel interrupt controllers, including ITSS.
+	  Some devices have extra features, such as Apollo Lake. The
+	  device has its own uclass since there are several operations
+	  involved.
+
 config JZ4780_EFUSE
 	bool "Ingenic JZ4780 eFUSE support"
 	depends on ARCH_JZ47XX
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 44c9e3e..28313e4 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -41,6 +41,7 @@
 obj-$(CONFIG_GDSYS_IOEP) += gdsys_ioep.o
 obj-$(CONFIG_GDSYS_RXAUI_CTRL) += gdsys_rxaui_ctrl.o
 obj-$(CONFIG_GDSYS_SOC) += gdsys_soc.o
+obj-$(CONFIG_IRQ) += irq-uclass.o
 obj-$(CONFIG_$(SPL_)I2C_EEPROM) += i2c_eeprom.o
 obj-$(CONFIG_IHS_FPGA) += ihs_fpga.o
 obj-$(CONFIG_IMX8) += imx8/
diff --git a/drivers/misc/irq-uclass.c b/drivers/misc/irq-uclass.c
new file mode 100644
index 0000000..d5182cf
--- /dev/null
+++ b/drivers/misc/irq-uclass.c
@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <irq.h>
+
+int irq_route_pmc_gpio_gpe(struct udevice *dev, uint pmc_gpe_num)
+{
+	const struct irq_ops *ops = irq_get_ops(dev);
+
+	if (!ops->route_pmc_gpio_gpe)
+		return -ENOSYS;
+
+	return ops->route_pmc_gpio_gpe(dev, pmc_gpe_num);
+}
+
+int irq_set_polarity(struct udevice *dev, uint irq, bool active_low)
+{
+	const struct irq_ops *ops = irq_get_ops(dev);
+
+	if (!ops->set_polarity)
+		return -ENOSYS;
+
+	return ops->set_polarity(dev, irq, active_low);
+}
+
+int irq_snapshot_polarities(struct udevice *dev)
+{
+	const struct irq_ops *ops = irq_get_ops(dev);
+
+	if (!ops->snapshot_polarities)
+		return -ENOSYS;
+
+	return ops->snapshot_polarities(dev);
+}
+
+int irq_restore_polarities(struct udevice *dev)
+{
+	const struct irq_ops *ops = irq_get_ops(dev);
+
+	if (!ops->restore_polarities)
+		return -ENOSYS;
+
+	return ops->restore_polarities(dev);
+}
+
+UCLASS_DRIVER(irq) = {
+	.id		= UCLASS_IRQ,
+	.name		= "irq",
+};
diff --git a/include/irq.h b/include/irq.h
new file mode 100644
index 0000000..01ded64
--- /dev/null
+++ b/include/irq.h
@@ -0,0 +1,88 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * IRQ is a type of interrupt controller used on recent Intel SoC.
+ *
+ * Copyright 2019 Google LLC
+ */
+
+#ifndef __irq_H
+#define __irq_H
+
+/**
+ * struct irq_ops - Operations for the IRQ
+ */
+struct irq_ops {
+	/**
+	 * route_pmc_gpio_gpe() - Get the GPIO for an event
+	 *
+	 * @dev: IRQ device
+	 * @pmc_gpe_num: Event number to check
+	 * @returns GPIO for the event, or -ENOENT if none
+	 */
+	int (*route_pmc_gpio_gpe)(struct udevice *dev, uint pmc_gpe_num);
+
+	/**
+	 * set_polarity() - Set the IRQ polarity
+	 *
+	 * @dev: IRQ device
+	 * @irq: Interrupt number to set
+	 * @active_low: true if active low, false for active high
+	 * @return 0 if OK, -EINVAL if @irq is invalid
+	 */
+	int (*set_polarity)(struct udevice *dev, uint irq, bool active_low);
+
+	/**
+	 * snapshot_polarities() - record IRQ polarities for later restore
+	 *
+	 * @dev: IRQ device
+	 * @return 0
+	 */
+	int (*snapshot_polarities)(struct udevice *dev);
+
+	/**
+	 * restore_polarities() - restore IRQ polarities
+	 *
+	 * @dev: IRQ device
+	 * @return 0
+	 */
+	int (*restore_polarities)(struct udevice *dev);
+};
+
+#define irq_get_ops(dev)	((struct irq_ops *)(dev)->driver->ops)
+
+/**
+ * irq_route_pmc_gpio_gpe() - Get the GPIO for an event
+ *
+ * @dev: IRQ device
+ * @pmc_gpe_num: Event number to check
+ * @returns GPIO for the event, or -ENOENT if none
+ */
+int irq_route_pmc_gpio_gpe(struct udevice *dev, uint pmc_gpe_num);
+
+/**
+ * irq_set_polarity() - Set the IRQ polarity
+ *
+ * @dev: IRQ device
+ * @irq: Interrupt number to set
+ * @active_low: true if active low, false for active high
+ * @return 0 if OK, -EINVAL if @irq is invalid
+ */
+int irq_set_polarity(struct udevice *dev, uint irq, bool active_low);
+
+/**
+ * irq_snapshot_polarities() - record IRQ polarities for later restore
+ *
+ * @dev: IRQ device
+ * @return 0
+ */
+int irq_snapshot_polarities(struct udevice *dev);
+
+/**
+ * irq_restore_polarities() - restore IRQ polarities
+ *
+ * @dev: IRQ device
+ * @return 0
+ */
+int irq_restore_polarities(struct udevice *dev);
+
+#endif