irq: Add a method to convert an interrupt to ACPI

When generating ACPI tables we need to convert IRQs in U-Boot to the ACPI
structures required by ACPI. This is a SoC-specific conversion and cannot
be handled by generic code, so add a new IRQ method to do the conversion.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Wolfgang Wallner <wolfgang.wallner@br-automation.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

drivers/misc/irq-uclass.c

@@ -152,8 +152,6 @@ int irq_request(struct udevice *dev, struct irq *irq)
 	const struct irq_ops *ops;
 
 	log_debug("(dev=%p, irq=%p)\n", dev, irq);
-	if (!irq)
-		return 0;
 	ops = irq_get_ops(dev);
 
 	irq->dev = dev;
@@ -175,6 +173,22 @@ int irq_first_device_type(enum irq_dev_t type, struct udevice **devp)
 	return 0;
 }
 
+#if CONFIG_IS_ENABLED(ACPIGEN)
+int irq_get_acpi(const struct irq *irq, struct acpi_irq *acpi_irq)
+{
+	struct irq_ops *ops;
+
+	if (!irq_is_valid(irq))
+		return -EINVAL;
+
+	ops = irq_get_ops(irq->dev);
+	if (!ops->get_acpi)
+		return -ENOSYS;
+
+	return ops->get_acpi(irq, acpi_irq);
+}
+#endif
+
 UCLASS_DRIVER(irq) = {
 	.id		= UCLASS_IRQ,
 	.name		= "irq",

drivers/misc/irq_sandbox.c

@@ -8,6 +8,7 @@
 #include <common.h>
 #include <dm.h>
 #include <irq.h>
+#include <acpi/acpi_device.h>
 #include <asm/test.h>
 
 /**
@@ -73,6 +74,18 @@ static int sandbox_irq_of_xlate(struct irq *irq,
 	return 0;
 }
 
+static __maybe_unused int sandbox_get_acpi(const struct irq *irq,
+					   struct acpi_irq *acpi_irq)
+{
+	acpi_irq->pin = irq->id;
+	acpi_irq->mode = ACPI_IRQ_LEVEL_TRIGGERED;
+	acpi_irq->polarity = ACPI_IRQ_ACTIVE_HIGH;
+	acpi_irq->shared = ACPI_IRQ_SHARED;
+	acpi_irq->wake = ACPI_IRQ_WAKE;
+
+	return 0;
+}
+
 static const struct irq_ops sandbox_irq_ops = {
 	.route_pmc_gpio_gpe	= sandbox_route_pmc_gpio_gpe,
 	.set_polarity		= sandbox_set_polarity,
@@ -80,6 +93,9 @@ static const struct irq_ops sandbox_irq_ops = {
 	.restore_polarities	= sandbox_restore_polarities,
 	.read_and_clear		= sandbox_irq_read_and_clear,
 	.of_xlate		= sandbox_irq_of_xlate,
+#if CONFIG_IS_ENABLED(ACPIGEN)
+	.get_acpi		= sandbox_get_acpi,
+#endif
 };
 
 static const struct udevice_id sandbox_irq_ids[] = {

include/acpi/acpi_device.h

@@ -13,6 +13,12 @@
 
 struct udevice;
 
+/* ACPI descriptor values for common descriptors: SERIAL_BUS means I2C */
+#define ACPI_DESCRIPTOR_LARGE		BIT(7)
+#define ACPI_DESCRIPTOR_INTERRUPT	(ACPI_DESCRIPTOR_LARGE | 9)
+#define ACPI_DESCRIPTOR_GPIO		(ACPI_DESCRIPTOR_LARGE | 12)
+#define ACPI_DESCRIPTOR_SERIAL_BUS	(ACPI_DESCRIPTOR_LARGE | 14)
+
 /* Length of a full path to an ACPI device */
 #define ACPI_PATH_MAX		30
 
@@ -31,6 +37,59 @@ enum acpi_dev_status {
 		ACPI_DSTATUS_SHOW_IN_UI,
 };
 
+/** enum acpi_irq_mode - edge/level trigger mode */
+enum acpi_irq_mode {
+	ACPI_IRQ_EDGE_TRIGGERED,
+	ACPI_IRQ_LEVEL_TRIGGERED,
+};
+
+/**
+ * enum acpi_irq_polarity - polarity of interrupt
+ *
+ * @ACPI_IRQ_ACTIVE_LOW - for ACPI_IRQ_EDGE_TRIGGERED this means falling edge
+ * @ACPI_IRQ_ACTIVE_HIGH - for ACPI_IRQ_EDGE_TRIGGERED this means rising edge
+ * @ACPI_IRQ_ACTIVE_BOTH - not meaningful for ACPI_IRQ_EDGE_TRIGGERED
+ */
+enum acpi_irq_polarity {
+	ACPI_IRQ_ACTIVE_LOW,
+	ACPI_IRQ_ACTIVE_HIGH,
+	ACPI_IRQ_ACTIVE_BOTH,
+};
+
+/**
+ * enum acpi_irq_shared - whether interrupt is shared or not
+ *
+ * @ACPI_IRQ_EXCLUSIVE: only this device uses the interrupt
+ * @ACPI_IRQ_SHARED: other devices may use this interrupt
+ */
+enum acpi_irq_shared {
+	ACPI_IRQ_EXCLUSIVE,
+	ACPI_IRQ_SHARED,
+};
+
+/** enum acpi_irq_wake - indicates whether this interrupt can wake the device */
+enum acpi_irq_wake {
+	ACPI_IRQ_NO_WAKE,
+	ACPI_IRQ_WAKE,
+};
+
+/**
+ * struct acpi_irq - representation of an ACPI interrupt
+ *
+ * @pin: ACPI pin that is monitored for the interrupt
+ * @mode: Edge/level triggering
+ * @polarity: Interrupt polarity
+ * @shared: Whether interrupt is shared or not
+ * @wake: Whether interrupt can wake the device from sleep
+ */
+struct acpi_irq {
+	unsigned int pin;
+	enum acpi_irq_mode mode;
+	enum acpi_irq_polarity polarity;
+	enum acpi_irq_shared shared;
+	enum acpi_irq_wake wake;
+};
+
 /**
  * acpi_device_path() - Get the full path to an ACPI device
  *

include/irq.h

@@ -8,6 +8,9 @@
 #ifndef __irq_H
 #define __irq_H
 
+struct acpi_irq;
+struct ofnode_phandle_args;
+
 /*
  * Interrupt controller types available. You can find a particular one with
  * irq_first_device_type()
@@ -24,10 +27,12 @@ enum irq_dev_t {
  *
  * @dev: IRQ device that handles this irq
  * @id: ID to identify this irq with the device
+ * @flags: Flags associated with this interrupt (IRQ_TYPE_...)
  */
 struct irq {
 	struct udevice *dev;
 	ulong id;
+	ulong flags;
 };
 
 /**
@@ -119,10 +124,36 @@ struct irq_ops {
 	 * @return 0 if OK, or a negative error code.
 	 */
 	int (*free)(struct irq *irq);
+
+#if CONFIG_IS_ENABLED(ACPIGEN)
+	/**
+	 * get_acpi() - Get the ACPI info for an irq
+	 *
+	 * This converts a irq to an ACPI structure for adding to the ACPI
+	 * tables.
+	 *
+	 * @irq:	irq to convert
+	 * @acpi_irq:	Output ACPI interrupt information
+	 * @return ACPI pin number or -ve on error
+	 */
+	int (*get_acpi)(const struct irq *irq, struct acpi_irq *acpi_irq);
+#endif
 };
 
 #define irq_get_ops(dev)	((struct irq_ops *)(dev)->driver->ops)
 
+/**
+ * irq_is_valid() - Check if an IRQ is valid
+ *
+ * @irq:	IRQ description containing device and ID, e.g. previously
+ *		returned by irq_get_by_index()
+ * @return true if valid, false if not
+ */
+static inline bool irq_is_valid(const struct irq *irq)
+{
+	return irq->dev != NULL;
+}
+
 /**
  * irq_route_pmc_gpio_gpe() - Get the GPIO for an event
  *
@@ -223,4 +254,16 @@ int irq_free(struct irq *irq);
  */
 int irq_first_device_type(enum irq_dev_t type, struct udevice **devp);
 
+/**
+ * irq_get_acpi() - Get the ACPI info for an irq
+ *
+ * This converts a irq to an ACPI structure for adding to the ACPI
+ * tables.
+ *
+ * @irq:	irq to convert
+ * @acpi_irq:	Output ACPI interrupt information
+ * @return ACPI pin number or -ve on error
+ */
+int irq_get_acpi(const struct irq *irq, struct acpi_irq *acpi_irq);
+
 #endif

test/dm/irq.c

@@ -8,6 +8,7 @@
 #include <common.h>
 #include <dm.h>
 #include <irq.h>
+#include <acpi/acpi_device.h>
 #include <asm/test.h>
 #include <dm/test.h>
 #include <test/ut.h>
@@ -75,3 +76,25 @@ static int dm_test_request(struct unit_test_state *uts)
 	return 0;
 }
 DM_TEST(dm_test_request, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+/* Test of irq_get_acpi() */
+static int dm_test_irq_get_acpi(struct unit_test_state *uts)
+{
+	struct acpi_irq airq;
+	struct udevice *dev;
+	struct irq irq;
+
+	ut_assertok(uclass_first_device_err(UCLASS_TEST_FDT, &dev));
+	ut_assertok(irq_get_by_index(dev, 0, &irq));
+
+	/* see sandbox_get_acpi() */
+	ut_assertok(irq_get_acpi(&irq, &airq));
+	ut_asserteq(3, airq.pin);
+	ut_asserteq(ACPI_IRQ_LEVEL_TRIGGERED, airq.mode);
+	ut_asserteq(ACPI_IRQ_ACTIVE_HIGH, airq.polarity);
+	ut_asserteq(ACPI_IRQ_SHARED, airq.shared);
+	ut_asserteq(ACPI_IRQ_WAKE, airq.wake);
+
+	return 0;
+}
+DM_TEST(dm_test_irq_get_acpi, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);