[PATCH v4 1/7] staging: fsl-mc: MC bus IRQ support

J. German Rivera German.Rivera at freescale.com
Tue Jun 9 21:59:02 UTC 2015


All the IRQs for DPAA2 objects in the same DPRC must use
the ICID of that DPRC, as their device Id in the GIC-ITS.
Thus, all these IRQs must share the same ITT table in GIC. As
a result, a pool of IRQs with the same device Id must be
preallocated per DPRC (fsl-mc bus instance). So, the fsl-mc
bus object allocator is extended to also provide services
to allocate IRQs to DPAA2 devices, from their parent fsl-mc bus
IRQ pool.

Also, the interrupt handler for DPRC IRQs is added. DPRC IRQs are
generated for hot plug events related to DPAA2 objects in a given
DPRC. These events include, creating/destroying DPAA2 objects in
the DPRC, changing the "plugged" state of DPAA2 objects and moving
objects between DPRCs.

Signed-off-by: J. German Rivera <German.Rivera at freescale.com>
Reviewed-by: Stuart Yoder <stuart.yoder at freescale.com>
---
Changes in v4:
- Addressed comments from Dan Carpenter and Greg Kroah-Hartman:
  * Removed all #ifdefed-out code
- Fixed new checkpatch "check" warnings

Changes in v3:
- Addressed comments from Dan Carpenter:
  * Removed nested redundant #ifdef GIC_ITS_MC_SUPPORT

Changes in v2:
- Addressed comments from Dan Carpenter and Scott Wood:
  * Removed unnecessary lines from commit messages
  * Replaced single error cleanup label with multiple labels, one for
    each error case and return directly when no cleanup is needed.
  * Fixed conditional alignment
  * Removed error messages for devm_kzalloc() errors
  * Removed WARN_ON in dprc_irq0_handler_thread()
  * Removed devm_kfree() calls

 drivers/staging/fsl-mc/bus/dprc-driver.c    | 353 ++++++++++++++++++++++++----
 drivers/staging/fsl-mc/bus/mc-allocator.c   | 102 +++++++-
 drivers/staging/fsl-mc/bus/mc-bus.c         | 156 +++++++++++-
 drivers/staging/fsl-mc/include/mc-private.h |  26 +-
 drivers/staging/fsl-mc/include/mc.h         |  29 ++-
 5 files changed, 599 insertions(+), 67 deletions(-)

diff --git a/drivers/staging/fsl-mc/bus/dprc-driver.c b/drivers/staging/fsl-mc/bus/dprc-driver.c
index 35c06cf..5351170 100644
--- a/drivers/staging/fsl-mc/bus/dprc-driver.c
+++ b/drivers/staging/fsl-mc/bus/dprc-driver.c
@@ -13,6 +13,7 @@
 #include "../include/mc-sys.h"
 #include <linux/module.h>
 #include <linux/slab.h>
+#include <linux/interrupt.h>
 #include "dprc-cmd.h"

 struct dprc_child_objs {
@@ -126,7 +127,7 @@ static void check_plugged_state_change(struct fsl_mc_device *mc_dev,
 				       struct dprc_obj_desc *obj_desc)
 {
 	int error;
-	uint32_t plugged_flag_at_mc =
+	u32 plugged_flag_at_mc =
 			(obj_desc->state & DPRC_OBJ_STATE_PLUGGED);

 	if (plugged_flag_at_mc !=
@@ -206,41 +207,11 @@ static void dprc_init_all_resource_pools(struct fsl_mc_device *mc_bus_dev)
 	}
 }

-static void dprc_cleanup_resource_pool(struct fsl_mc_device *mc_bus_dev,
-				       enum fsl_mc_pool_type pool_type)
-{
-	struct fsl_mc_resource *resource;
-	struct fsl_mc_resource *next;
-	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
-	struct fsl_mc_resource_pool *res_pool =
-					&mc_bus->resource_pools[pool_type];
-	int free_count = 0;
-
-	WARN_ON(res_pool->type != pool_type);
-	WARN_ON(res_pool->free_count != res_pool->max_count);
-
-	list_for_each_entry_safe(resource, next, &res_pool->free_list, node) {
-		free_count++;
-		WARN_ON(resource->type != res_pool->type);
-		WARN_ON(resource->parent_pool != res_pool);
-		devm_kfree(&mc_bus_dev->dev, resource);
-	}
-
-	WARN_ON(free_count != res_pool->free_count);
-}
-
-static void dprc_cleanup_all_resource_pools(struct fsl_mc_device *mc_bus_dev)
-{
-	int pool_type;
-
-	for (pool_type = 0; pool_type < FSL_MC_NUM_POOL_TYPES; pool_type++)
-		dprc_cleanup_resource_pool(mc_bus_dev, pool_type);
-}
-
 /**
  * dprc_scan_objects - Discover objects in a DPRC
  *
  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
+ * @total_irq_count: total number of IRQs needed by objects in the DPRC.
  *
  * Detects objects added and removed from a DPRC and synchronizes the
  * state of the Linux bus driver, MC by adding and removing
@@ -254,11 +225,13 @@ static void dprc_cleanup_all_resource_pools(struct fsl_mc_device *mc_bus_dev)
  * populated before they can get allocation requests from probe callbacks
  * of the device drivers for the non-allocatable devices.
  */
-int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev)
+int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev,
+		      unsigned int *total_irq_count)
 {
 	int num_child_objects;
 	int dprc_get_obj_failures;
 	int error;
+	unsigned int irq_count = mc_bus_dev->obj_desc.irq_count;
 	struct dprc_obj_desc *child_obj_desc_array = NULL;

 	error = dprc_get_obj_count(mc_bus_dev->mc_io,
@@ -274,9 +247,9 @@ int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev)
 		int i;

 		child_obj_desc_array =
-		    devm_kmalloc_array(&mc_bus_dev->dev, num_child_objects,
-				       sizeof(*child_obj_desc_array),
-				       GFP_KERNEL);
+		    kmalloc_array(num_child_objects,
+				  sizeof(*child_obj_desc_array),
+				  GFP_KERNEL);
 		if (!child_obj_desc_array)
 			return -ENOMEM;

@@ -305,6 +278,7 @@ int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev)
 				continue;
 			}

+			irq_count += obj_desc->irq_count;
 			dev_dbg(&mc_bus_dev->dev,
 				"Discovered object: type %s, id %d\n",
 				obj_desc->type, obj_desc->id);
@@ -317,15 +291,14 @@ int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev)
 		}
 	}

+	*total_irq_count = irq_count;
 	dprc_remove_devices(mc_bus_dev, child_obj_desc_array,
 			    num_child_objects);

 	dprc_add_new_devices(mc_bus_dev, child_obj_desc_array,
 			     num_child_objects);

-	if (child_obj_desc_array)
-		devm_kfree(&mc_bus_dev->dev, child_obj_desc_array);
-
+	kfree(child_obj_desc_array);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(dprc_scan_objects);
@@ -339,9 +312,10 @@ EXPORT_SYMBOL_GPL(dprc_scan_objects);
  * bus driver with the actual state of the MC by adding and removing
  * devices as appropriate.
  */
-int dprc_scan_container(struct fsl_mc_device *mc_bus_dev)
+static int dprc_scan_container(struct fsl_mc_device *mc_bus_dev)
 {
 	int error;
+	unsigned int irq_count;
 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);

 	dprc_init_all_resource_pools(mc_bus_dev);
@@ -350,17 +324,280 @@ int dprc_scan_container(struct fsl_mc_device *mc_bus_dev)
 	 * Discover objects in the DPRC:
 	 */
 	mutex_lock(&mc_bus->scan_mutex);
-	error = dprc_scan_objects(mc_bus_dev);
+	error = dprc_scan_objects(mc_bus_dev, &irq_count);
 	mutex_unlock(&mc_bus->scan_mutex);
 	if (error < 0)
-		goto error;
+		return error;
+
+	if (!mc_bus->irq_resources) {
+		irq_count += FSL_MC_IRQ_POOL_MAX_EXTRA_IRQS;
+		error = fsl_mc_populate_irq_pool(mc_bus, irq_count);
+		if (error < 0)
+			return error;
+	}
+
+	return 0;
+}
+
+/**
+ * dprc_irq0_handler - Regular ISR for DPRC interrupt 0
+ *
+ * @irq: IRQ number of the interrupt being handled
+ * @arg: Pointer to device structure
+ */
+static irqreturn_t dprc_irq0_handler(int irq_num, void *arg)
+{
+	return IRQ_WAKE_THREAD;
+}
+
+/**
+ * dprc_irq0_handler_thread - Handler thread function for DPRC interrupt 0
+ *
+ * @irq: IRQ number of the interrupt being handled
+ * @arg: Pointer to device structure
+ */
+static irqreturn_t dprc_irq0_handler_thread(int irq_num, void *arg)
+{
+	int error;
+	u32 status;
+	struct device *dev = (struct device *)arg;
+	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
+	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
+	struct fsl_mc_io *mc_io = mc_dev->mc_io;
+	int irq_index = 0;
+
+	dev_dbg(dev, "DPRC IRQ %d\n", irq_num);
+	if (WARN_ON(!(mc_dev->flags & FSL_MC_IS_DPRC)))
+		return IRQ_HANDLED;
+
+	mutex_lock(&mc_bus->scan_mutex);
+	if (WARN_ON(mc_dev->irqs[irq_index]->irq_number != (u32)irq_num))
+		goto out;
+
+	error = dprc_get_irq_status(mc_io, mc_dev->mc_handle, irq_index,
+				    &status);
+	if (error < 0) {
+		dev_err(dev,
+			"dprc_get_irq_status() failed: %d\n", error);
+		goto out;
+	}
+
+	error = dprc_clear_irq_status(mc_io, mc_dev->mc_handle, irq_index,
+				      status);
+	if (error < 0) {
+		dev_err(dev,
+			"dprc_clear_irq_status() failed: %d\n", error);
+		goto out;
+	}
+
+	if (status & (DPRC_IRQ_EVENT_OBJ_ADDED |
+		      DPRC_IRQ_EVENT_OBJ_REMOVED |
+		      DPRC_IRQ_EVENT_CONTAINER_DESTROYED |
+		      DPRC_IRQ_EVENT_OBJ_DESTROYED |
+		      DPRC_IRQ_EVENT_OBJ_CREATED)) {
+		unsigned int irq_count;
+
+		error = dprc_scan_objects(mc_dev, &irq_count);
+		if (error < 0) {
+			dev_err(dev, "dprc_scan_objects() failed: %d\n", error);
+			goto out;
+		}
+
+		if (irq_count >
+		    mc_bus->resource_pools[FSL_MC_POOL_IRQ].max_count) {
+			dev_warn(dev,
+				 "IRQs needed (%u) exceed IRQs preallocated (%u)\n",
+				 irq_count,
+				 mc_bus->resource_pools[FSL_MC_POOL_IRQ].
+								max_count);
+		}
+	}
+
+out:
+	mutex_unlock(&mc_bus->scan_mutex);
+	return IRQ_HANDLED;
+}
+
+/*
+ * Disable and clear interrupts for a given DPRC object
+ */
+static int disable_dprc_irqs(struct fsl_mc_device *mc_dev)
+{
+	int i;
+	int error;
+	struct fsl_mc_io *mc_io = mc_dev->mc_io;
+	int irq_count = mc_dev->obj_desc.irq_count;
+
+	if (WARN_ON(irq_count == 0))
+		return -EINVAL;
+
+	for (i = 0; i < irq_count; i++) {
+		/*
+		 * Disable generation of interrupt i, while we configure it:
+		 */
+		error = dprc_set_irq_enable(mc_io, mc_dev->mc_handle, i, 0);
+		if (error < 0) {
+			dev_err(&mc_dev->dev,
+				"dprc_set_irq_enable() failed: %d\n", error);
+
+			return error;
+		}
+
+		/*
+		 * Disable all interrupt causes for interrupt i:
+		 */
+		error = dprc_set_irq_mask(mc_io, mc_dev->mc_handle, i, 0x0);
+		if (error < 0) {
+			dev_err(&mc_dev->dev,
+				"dprc_set_irq_mask() failed: %d\n", error);
+
+			return error;
+		}
+
+		/*
+		 * Clear any leftover interrupt i:
+		 */
+		error = dprc_clear_irq_status(mc_io, mc_dev->mc_handle, i,
+					      ~0x0U);
+		if (error < 0) {
+			dev_err(&mc_dev->dev,
+				"dprc_clear_irq_status() failed: %d\n",
+				error);
+			return error;
+		}
+	}
+
+	return 0;
+}
+
+static int register_dprc_irq_handlers(struct fsl_mc_device *mc_dev)
+{
+	static const struct irq_handler {
+		irq_handler_t irq_handler;
+		irq_handler_t irq_handler_thread;
+		const char *irq_name;
+	} irq_handlers[] = {
+		[0] = {
+			.irq_handler = dprc_irq0_handler,
+			.irq_handler_thread = dprc_irq0_handler_thread,
+			.irq_name = "FSL MC DPRC irq0",
+		},
+	};
+
+	unsigned int i;
+	int error;
+	struct fsl_mc_device_irq *irq;
+	int irq_count = mc_dev->obj_desc.irq_count;
+
+	if (WARN_ON(irq_count != ARRAY_SIZE(irq_handlers)))
+		return -EINVAL;
+
+	for (i = 0; i < ARRAY_SIZE(irq_handlers); i++) {
+		irq = mc_dev->irqs[i];
+		error = devm_request_threaded_irq(&mc_dev->dev,
+						  irq->irq_number,
+						  irq_handlers[i].irq_handler,
+						  irq_handlers[i].
+							irq_handler_thread,
+						  IRQF_NO_SUSPEND |
+							IRQF_ONESHOT,
+						  irq_handlers[i].irq_name,
+						  &mc_dev->dev);
+		if (error < 0) {
+			dev_err(&mc_dev->dev,
+				"devm_request_threaded_irq() failed: %d\n",
+				error);
+			return error;
+		}
+
+		/*
+		 * Program the MSI (paddr, value) pair in the device:
+		 *
+		 * TODO: This needs to be moved to mc_bus_msi_domain_write_msg()
+		 * when the MC object-independent dprc_set_irq() flib API
+		 * becomes available
+		 */
+		error = dprc_set_irq(mc_dev->mc_io, mc_dev->mc_handle,
+				     i, irq->msi_paddr,
+				     irq->msi_value,
+				     irq->irq_number);
+		if (error < 0) {
+			dev_err(&mc_dev->dev,
+				"mc_set_irq() failed: %d\n", error);
+			return error;
+		}
+	}
+
+	return 0;
+}
+
+static int enable_dprc_irqs(struct fsl_mc_device *mc_dev)
+{
+	int i;
+	int error;
+	int irq_count = mc_dev->obj_desc.irq_count;
+
+	for (i = 0; i < irq_count; i++) {
+		/*
+		 * Enable all interrupt causes for the interrupt:
+		 */
+		error = dprc_set_irq_mask(mc_dev->mc_io,
+					  mc_dev->mc_handle,
+					  i,
+					  ~0x0u);
+		if (error < 0) {
+			dev_err(&mc_dev->dev,
+				"dprc_set_irq_mask() failed: %d\n", error);
+
+			return error;
+		}
+
+		/*
+		 * Enable generation of the interrupt:
+		 */
+		error = dprc_set_irq_enable(mc_dev->mc_io,
+					    mc_dev->mc_handle,
+					    i, 1);
+		if (error < 0) {
+			dev_err(&mc_dev->dev,
+				"dprc_set_irq_enable() failed: %d\n", error);
+
+			return error;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * Setup interrupts for a given DPRC device
+ */
+static int dprc_setup_irqs(struct fsl_mc_device *mc_dev)
+{
+	int error;
+
+	error = fsl_mc_allocate_irqs(mc_dev);
+	if (error < 0)
+		return error;
+
+	error = disable_dprc_irqs(mc_dev);
+	if (error < 0)
+		goto error_free_irqs;
+
+	error = register_dprc_irq_handlers(mc_dev);
+	if (error < 0)
+		goto error_free_irqs;
+
+	error = enable_dprc_irqs(mc_dev);
+	if (error < 0)
+		goto error_free_irqs;

 	return 0;
-error:
-	dprc_cleanup_all_resource_pools(mc_bus_dev);
+
+error_free_irqs:
+	fsl_mc_free_irqs(mc_dev);
 	return error;
 }
-EXPORT_SYMBOL_GPL(dprc_scan_container);

 /**
  * dprc_probe - callback invoked when a DPRC is being bound to this driver
@@ -415,10 +652,20 @@ static int dprc_probe(struct fsl_mc_device *mc_dev)
 	if (error < 0)
 		goto error_cleanup_open;

+	/*
+	 * Configure interrupts for the DPRC object associated with this MC bus:
+	 */
+	error = dprc_setup_irqs(mc_dev);
+	if (error < 0)
+		goto error_cleanup_open;
+
 	dev_info(&mc_dev->dev, "DPRC device bound to driver");
 	return 0;

 error_cleanup_open:
+	if (mc_bus->irq_resources)
+		fsl_mc_cleanup_irq_pool(mc_bus);
+
 	(void)dprc_close(mc_dev->mc_io, mc_dev->mc_handle);

 error_cleanup_mc_io:
@@ -426,6 +673,15 @@ error_cleanup_mc_io:
 	return error;
 }

+/*
+ * Tear down interrupts for a given DPRC object
+ */
+static void dprc_teardown_irqs(struct fsl_mc_device *mc_dev)
+{
+	(void)disable_dprc_irqs(mc_dev);
+	fsl_mc_free_irqs(mc_dev);
+}
+
 /**
  * dprc_remove - callback invoked when a DPRC is being unbound from this driver
  *
@@ -439,18 +695,23 @@ error_cleanup_mc_io:
 static int dprc_remove(struct fsl_mc_device *mc_dev)
 {
 	int error;
+	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);

 	if (WARN_ON(strcmp(mc_dev->obj_desc.type, "dprc") != 0))
 		return -EINVAL;
 	if (WARN_ON(!mc_dev->mc_io))
 		return -EINVAL;

+	if (WARN_ON(!mc_bus->irq_resources))
+		return -EINVAL;
+
+	dprc_teardown_irqs(mc_dev);
 	device_for_each_child(&mc_dev->dev, NULL, __fsl_mc_device_remove);
-	dprc_cleanup_all_resource_pools(mc_dev);
 	error = dprc_close(mc_dev->mc_io, mc_dev->mc_handle);
 	if (error < 0)
 		dev_err(&mc_dev->dev, "dprc_close() failed: %d\n", error);

+	fsl_mc_cleanup_irq_pool(mc_bus);
 	dev_info(&mc_dev->dev, "DPRC device unbound from driver");
 	return 0;
 }
diff --git a/drivers/staging/fsl-mc/bus/mc-allocator.c b/drivers/staging/fsl-mc/bus/mc-allocator.c
index e36235d..aa8280a 100644
--- a/drivers/staging/fsl-mc/bus/mc-allocator.c
+++ b/drivers/staging/fsl-mc/bus/mc-allocator.c
@@ -66,8 +66,6 @@ static int __must_check fsl_mc_resource_pool_add_device(struct fsl_mc_bus
 				GFP_KERNEL);
 	if (!resource) {
 		error = -ENOMEM;
-		dev_err(&mc_bus_dev->dev,
-			"Failed to allocate memory for fsl_mc_resource\n");
 		goto out;
 	}

@@ -145,8 +143,6 @@ static int __must_check fsl_mc_resource_pool_remove_device(struct fsl_mc_device
 	INIT_LIST_HEAD(&resource->node);
 	res_pool->free_count--;
 	res_pool->max_count--;
-
-	devm_kfree(&mc_bus_dev->dev, resource);
 	mc_dev->resource = NULL;
 	error = 0;
 out:
@@ -160,6 +156,7 @@ static const char *const fsl_mc_pool_type_strings[] = {
 	[FSL_MC_POOL_DPMCP] = "dpmcp",
 	[FSL_MC_POOL_DPBP] = "dpbp",
 	[FSL_MC_POOL_DPCON] = "dpcon",
+	[FSL_MC_POOL_IRQ] = "irq",
 };

 static int __must_check object_type_to_pool_type(const char *object_type,
@@ -473,6 +470,103 @@ void fsl_mc_object_free(struct fsl_mc_device *mc_adev)
 EXPORT_SYMBOL_GPL(fsl_mc_object_free);

 /**
+ * It allocates the IRQs required by a given MC object device. The
+ * IRQs are allocated from the interrupt pool associated with the
+ * MC bus that contains the device, if the device is not a DPRC device.
+ * Otherwise, the IRQs are allocated from the interrupt pool associated
+ * with the MC bus that represents the DPRC device itself.
+ */
+int __must_check fsl_mc_allocate_irqs(struct fsl_mc_device *mc_dev)
+{
+	int i;
+	int irq_count;
+	int res_allocated_count = 0;
+	int error = -EINVAL;
+	struct fsl_mc_device_irq **irqs = NULL;
+	struct fsl_mc_bus *mc_bus;
+	struct fsl_mc_resource_pool *res_pool;
+
+	if (WARN_ON(mc_dev->irqs))
+		return -EINVAL;
+
+	irq_count = mc_dev->obj_desc.irq_count;
+	if (WARN_ON(irq_count == 0))
+		return -EINVAL;
+
+	if (strcmp(mc_dev->obj_desc.type, "dprc") == 0)
+		mc_bus = to_fsl_mc_bus(mc_dev);
+	else
+		mc_bus = to_fsl_mc_bus(to_fsl_mc_device(mc_dev->dev.parent));
+
+	if (WARN_ON(!mc_bus->irq_resources))
+		return -EINVAL;
+
+	res_pool = &mc_bus->resource_pools[FSL_MC_POOL_IRQ];
+	if (res_pool->free_count < irq_count) {
+		dev_err(&mc_dev->dev,
+			"Not able to allocate %u irqs for device\n", irq_count);
+		return -ENOSPC;
+	}
+
+	irqs = devm_kzalloc(&mc_dev->dev, irq_count * sizeof(irqs[0]),
+			    GFP_KERNEL);
+	if (!irqs)
+		return -ENOMEM;
+
+	for (i = 0; i < irq_count; i++) {
+		struct fsl_mc_resource *resource;
+
+		error = fsl_mc_resource_allocate(mc_bus, FSL_MC_POOL_IRQ,
+						 &resource);
+		if (error < 0)
+			goto error_resource_alloc;
+
+		irqs[i] = to_fsl_mc_irq(resource);
+		res_allocated_count++;
+	}
+
+	mc_dev->irqs = irqs;
+	return 0;
+
+error_resource_alloc:
+	for (i = 0; i < res_allocated_count; i++)
+		fsl_mc_resource_free(&irqs[i]->resource);
+
+	return error;
+}
+EXPORT_SYMBOL_GPL(fsl_mc_allocate_irqs);
+
+/*
+ * It frees the IRQs that were allocated for a MC object device, by
+ * returning them to the corresponding interrupt pool.
+ */
+void fsl_mc_free_irqs(struct fsl_mc_device *mc_dev)
+{
+	int i;
+	int irq_count;
+	struct fsl_mc_bus *mc_bus;
+
+	if (WARN_ON(!mc_dev->irqs))
+		return;
+
+	irq_count = mc_dev->obj_desc.irq_count;
+
+	if (strcmp(mc_dev->obj_desc.type, "dprc") == 0)
+		mc_bus = to_fsl_mc_bus(mc_dev);
+	else
+		mc_bus = to_fsl_mc_bus(to_fsl_mc_device(mc_dev->dev.parent));
+
+	if (WARN_ON(!mc_bus->irq_resources))
+		return;
+
+	for (i = 0; i < irq_count; i++)
+		fsl_mc_resource_free(&mc_dev->irqs[i]->resource);
+
+	mc_dev->irqs = NULL;
+}
+EXPORT_SYMBOL_GPL(fsl_mc_free_irqs);
+
+/**
  * fsl_mc_allocator_probe - callback invoked when an allocatable device is
  * being added to the system
  */
diff --git a/drivers/staging/fsl-mc/bus/mc-bus.c b/drivers/staging/fsl-mc/bus/mc-bus.c
index 766a659..9d98828 100644
--- a/drivers/staging/fsl-mc/bus/mc-bus.c
+++ b/drivers/staging/fsl-mc/bus/mc-bus.c
@@ -15,11 +15,27 @@
 #include <linux/of_address.h>
 #include <linux/ioport.h>
 #include <linux/slab.h>
+#include <linux/irqchip/arm-gic-v3.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
 #include <linux/limits.h>
+#include <linux/bitops.h>
 #include "../include/dpmng.h"
 #include "../include/mc-sys.h"
 #include "dprc-cmd.h"

+/*
+ * IOMMU stream ID flags
+ */
+#define STREAM_ID_PL_MASK   BIT(9)	    /* privilege level */
+#define STREAM_ID_BMT_MASK  BIT(8)	    /* bypass memory translation */
+#define STREAM_ID_VA_MASK   BIT(7)	    /* virtual address translation
+					     * (two-stage translation) */
+#define STREAM_ID_ICID_MASK (BIT(7) - 1)    /* isolation context ID
+					     * (translation context) */
+
+#define MAX_STREAM_ID_ICID  STREAM_ID_ICID_MASK
+
 static struct kmem_cache *mc_dev_cache;

 /**
@@ -295,8 +311,9 @@ static int fsl_mc_device_get_mmio_regions(struct fsl_mc_device *mc_dev,
 					  &regions[i].start);
 		if (error < 0) {
 			dev_err(parent_dev,
-				"Invalid MC address: %#llx\n",
-				region_desc.base_paddr);
+				"Invalid MC address: %#llx (for %s.%d\'s region %d)\n",
+				region_desc.base_paddr,
+				obj_desc->type, obj_desc->id, i);
 			goto error_cleanup_regions;
 		}

@@ -335,7 +352,7 @@ int fsl_mc_device_add(struct dprc_obj_desc *obj_desc,
 		/*
 		 * Allocate an MC bus device object:
 		 */
-		mc_bus = devm_kzalloc(parent_dev, sizeof(*mc_bus), GFP_KERNEL);
+		mc_bus = kzalloc(sizeof(*mc_bus), GFP_KERNEL);
 		if (!mc_bus)
 			return -ENOMEM;

@@ -437,10 +454,10 @@ int fsl_mc_device_add(struct dprc_obj_desc *obj_desc,

 error_cleanup_dev:
 	kfree(mc_dev->regions);
-	if (mc_bus)
-		devm_kfree(parent_dev, mc_bus);
-	else
+	if (!mc_bus)
 		kmem_cache_free(mc_dev_cache, mc_dev);
+	else
+		kfree(mc_bus);

 	return error;
 }
@@ -475,13 +492,120 @@ void fsl_mc_device_remove(struct fsl_mc_device *mc_dev)
 			fsl_mc_bus_type.dev_root = NULL;
 	}

-	if (mc_bus)
-		devm_kfree(mc_dev->dev.parent, mc_bus);
-	else
+	if (!mc_bus)
 		kmem_cache_free(mc_dev_cache, mc_dev);
+	else
+		kfree(mc_bus);
 }
 EXPORT_SYMBOL_GPL(fsl_mc_device_remove);

+static int create_mc_irq_domain(struct platform_device *mc_pdev,
+				struct irq_domain **new_irq_domain)
+{
+	int error;
+	struct device_node *its_of_node;
+	struct irq_domain *its_domain;
+	struct device_node *mc_of_node = mc_pdev->dev.of_node;
+
+	its_of_node = of_parse_phandle(mc_of_node, "msi-parent", 0);
+	if (!its_of_node) {
+		dev_err(&mc_pdev->dev,
+			"msi-parent phandle missing for %s\n",
+			mc_of_node->full_name);
+		return -ENOENT;
+	}
+
+	/*
+	 * Extract MSI parent node:
+	 */
+	its_domain = irq_find_host(its_of_node);
+	if (!its_domain) {
+		dev_err(&mc_pdev->dev, "Unable to find parent domain\n");
+		error = -ENOENT;
+		goto cleanup_its_of_node;
+	}
+
+	/*
+	 * TODO: Call msi_create_irq_domain() to create IRQ domain for MC MSIs
+	 * when complete GIC-ITS support * for generic MSIs is upstream. On
+	 * success, set mc->gic_supported to true.
+	 */
+	*new_irq_domain = NULL;
+	dev_err(&mc_pdev->dev, "Cannot create MSI domain\n");
+	error = -ENOTSUPP;
+
+cleanup_its_of_node:
+	of_node_put(its_of_node);
+	return error;
+}
+
+/*
+ * Initialize the interrupt pool associated with a MC bus.
+ * It allocates a block of IRQs from the GIC-ITS
+ */
+int __must_check fsl_mc_populate_irq_pool(struct fsl_mc_bus *mc_bus,
+					  unsigned int irq_count)
+{
+	unsigned int i;
+	struct fsl_mc_device_irq *irq_resources;
+	struct fsl_mc_device_irq *irq_res;
+	struct fsl_mc_device *mc_bus_dev = &mc_bus->mc_dev;
+	struct fsl_mc_resource_pool *res_pool =
+			&mc_bus->resource_pools[FSL_MC_POOL_IRQ];
+
+	if (WARN_ON(irq_count == 0 ||
+		    irq_count > FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS))
+		return -EINVAL;
+
+	irq_resources =
+		devm_kzalloc(&mc_bus_dev->dev,
+			     sizeof(*irq_resources) * irq_count,
+			     GFP_KERNEL);
+	if (!irq_resources)
+		return -ENOMEM;
+
+	for (i = 0; i < irq_count; i++) {
+		irq_res = &irq_resources[i];
+		/*
+		 * TODO: set irq_res->msi_paddr and irq_res->irq_number with
+		 * values obtained from the GIC-ITS.
+		 * Also, set irq_res->resource.id to irq_number.
+		 */
+		irq_res->resource.type = res_pool->type;
+		irq_res->resource.data = irq_res;
+		irq_res->resource.parent_pool = res_pool;
+		INIT_LIST_HEAD(&irq_res->resource.node);
+		list_add_tail(&irq_res->resource.node, &res_pool->free_list);
+	}
+
+	res_pool->max_count = irq_count;
+	res_pool->free_count = irq_count;
+	mc_bus->irq_resources = irq_resources;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(fsl_mc_populate_irq_pool);
+
+/**
+ * Teardown the interrupt pool associated with an MC bus.
+ * It frees the IRQs that were allocated to the pool, back to the GIC-ITS.
+ */
+void fsl_mc_cleanup_irq_pool(struct fsl_mc_bus *mc_bus)
+{
+	struct fsl_mc_resource_pool *res_pool =
+			&mc_bus->resource_pools[FSL_MC_POOL_IRQ];
+
+	if (WARN_ON(res_pool->max_count == 0))
+		return;
+
+	if (WARN_ON(res_pool->free_count != res_pool->max_count))
+		return;
+
+	res_pool->max_count = 0;
+	res_pool->free_count = 0;
+	mc_bus->irq_resources = NULL;
+}
+EXPORT_SYMBOL_GPL(fsl_mc_cleanup_irq_pool);
+
 static int parse_mc_ranges(struct device *dev,
 			   int *paddr_cells,
 			   int *mc_addr_cells,
@@ -600,7 +724,7 @@ static int fsl_mc_bus_probe(struct platform_device *pdev)
 	struct fsl_mc_io *mc_io = NULL;
 	int container_id;
 	phys_addr_t mc_portal_phys_addr;
-	uint32_t mc_portal_size;
+	u32 mc_portal_size;
 	struct mc_version mc_version;
 	struct resource res;

@@ -611,6 +735,9 @@ static int fsl_mc_bus_probe(struct platform_device *pdev)
 		return -ENOMEM;

 	platform_set_drvdata(pdev, mc);
+	error = create_mc_irq_domain(pdev, &mc->irq_domain);
+	if (error < 0)
+		return error;

 	/*
 	 * Get physical address of MC portal for the root DPRC:
@@ -620,7 +747,7 @@ static int fsl_mc_bus_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev,
 			"of_address_to_resource() failed for %s\n",
 			pdev->dev.of_node->full_name);
-		return error;
+		goto error_cleanup_irq_domain;
 	}

 	mc_portal_phys_addr = res.start;
@@ -628,7 +755,7 @@ static int fsl_mc_bus_probe(struct platform_device *pdev)
 	error = fsl_create_mc_io(&pdev->dev, mc_portal_phys_addr,
 				 mc_portal_size, NULL, 0, &mc_io);
 	if (error < 0)
-		return error;
+		goto error_cleanup_irq_domain;

 	error = mc_get_version(mc_io, &mc_version);
 	if (error != 0) {
@@ -673,6 +800,7 @@ static int fsl_mc_bus_probe(struct platform_device *pdev)
 	obj_desc.id = container_id;
 	obj_desc.ver_major = DPRC_VER_MAJOR;
 	obj_desc.ver_minor = DPRC_VER_MINOR;
+	obj_desc.irq_count = 1;
 	obj_desc.region_count = 0;

 	error = fsl_mc_device_add(&obj_desc, mc_io, &pdev->dev, &mc_bus_dev);
@@ -684,6 +812,9 @@ static int fsl_mc_bus_probe(struct platform_device *pdev)

 error_cleanup_mc_io:
 	fsl_destroy_mc_io(mc_io);
+
+error_cleanup_irq_domain:
+	irq_domain_remove(mc->irq_domain);
 	return error;
 }

@@ -698,6 +829,7 @@ static int fsl_mc_bus_remove(struct platform_device *pdev)
 	if (WARN_ON(&mc->root_mc_bus_dev->dev != fsl_mc_bus_type.dev_root))
 		return -EINVAL;

+	irq_domain_remove(mc->irq_domain);
 	fsl_mc_device_remove(mc->root_mc_bus_dev);
 	dev_info(&pdev->dev, "Root MC bus device removed");
 	return 0;
diff --git a/drivers/staging/fsl-mc/include/mc-private.h b/drivers/staging/fsl-mc/include/mc-private.h
index c045f49..6e33942 100644
--- a/drivers/staging/fsl-mc/include/mc-private.h
+++ b/drivers/staging/fsl-mc/include/mc-private.h
@@ -27,12 +27,26 @@
 	 strcmp(_obj_type, "dpcon") == 0)

 /**
+ * Maximum number of total IRQs that can be pre-allocated for an MC bus'
+ * IRQ pool
+ */
+#define FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS	256
+
+/**
+ * Maximum number of extra IRQs pre-reallocated for an MC bus' IRQ pool,
+ * to be used by dynamically created MC objects
+ */
+#define FSL_MC_IRQ_POOL_MAX_EXTRA_IRQS	64
+
+/**
  * struct fsl_mc - Private data of a "fsl,qoriq-mc" platform device
  * @root_mc_bus_dev: MC object device representing the root DPRC
+ * @irq_domain: IRQ domain for the fsl-mc bus type
  * @addr_translation_ranges: array of bus to system address translation ranges
  */
 struct fsl_mc {
 	struct fsl_mc_device *root_mc_bus_dev;
+	struct irq_domain *irq_domain;
 	uint8_t num_translation_ranges;
 	struct fsl_mc_addr_translation_range *translation_ranges;
 };
@@ -76,11 +90,13 @@ struct fsl_mc_resource_pool {
  * @resource_pools: array of resource pools (one pool per resource type)
  * for this MC bus. These resources represent allocatable entities
  * from the physical DPRC.
+ * @irq_resources: Pointer to array of IRQ objects for the IRQ pool.
  * @scan_mutex: Serializes bus scanning
  */
 struct fsl_mc_bus {
 	struct fsl_mc_device mc_dev;
 	struct fsl_mc_resource_pool resource_pools[FSL_MC_NUM_POOL_TYPES];
+	struct fsl_mc_device_irq *irq_resources;
 	struct mutex scan_mutex;    /* serializes bus scanning */
 };

@@ -94,9 +110,8 @@ int __must_check fsl_mc_device_add(struct dprc_obj_desc *obj_desc,

 void fsl_mc_device_remove(struct fsl_mc_device *mc_dev);

-int dprc_scan_container(struct fsl_mc_device *mc_bus_dev);
-
-int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev);
+int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev,
+		      unsigned int *total_irq_count);

 int __init dprc_driver_init(void);

@@ -113,4 +128,9 @@ int __must_check fsl_mc_resource_allocate(struct fsl_mc_bus *mc_bus,

 void fsl_mc_resource_free(struct fsl_mc_resource *resource);

+int __must_check fsl_mc_populate_irq_pool(struct fsl_mc_bus *mc_bus,
+					  unsigned int irq_count);
+
+void fsl_mc_cleanup_irq_pool(struct fsl_mc_bus *mc_bus);
+
 #endif /* _FSL_MC_PRIVATE_H_ */
diff --git a/drivers/staging/fsl-mc/include/mc.h b/drivers/staging/fsl-mc/include/mc.h
index fa02ef0..c543a84 100644
--- a/drivers/staging/fsl-mc/include/mc.h
+++ b/drivers/staging/fsl-mc/include/mc.h
@@ -14,6 +14,7 @@
 #include <linux/device.h>
 #include <linux/mod_devicetable.h>
 #include <linux/list.h>
+#include <linux/interrupt.h>
 #include "../include/dprc.h"

 #define FSL_MC_VENDOR_FREESCALE	0x1957
@@ -61,8 +62,8 @@ struct fsl_mc_driver {
 struct fsl_mc_device_match_id {
 	uint16_t vendor;
 	const char obj_type[16];
-	uint32_t ver_major;
-	uint32_t ver_minor;
+	u32 ver_major;
+	u32 ver_minor;
 };

 /**
@@ -75,6 +76,7 @@ enum fsl_mc_pool_type {
 	FSL_MC_POOL_DPMCP = 0x0,    /* corresponds to "dpmcp" in the MC */
 	FSL_MC_POOL_DPBP,	    /* corresponds to "dpbp" in the MC */
 	FSL_MC_POOL_DPCON,	    /* corresponds to "dpcon" in the MC */
+	FSL_MC_POOL_IRQ,

 	/*
 	 * NOTE: New resource pool types must be added before this entry
@@ -104,6 +106,23 @@ struct fsl_mc_resource {
 };

 /**
+ * struct fsl_mc_device_irq - MC object device message-based interrupt
+ * @msi_paddr: message-based interrupt physical address
+ * @msi_value: message-based interrupt data value
+ * @irq_number: Linux IRQ number assigned to the interrupt
+ * @resource: MC generic resource associated with the interrupt
+ */
+struct fsl_mc_device_irq {
+	phys_addr_t msi_paddr;
+	u32 msi_value;
+	u32 irq_number;
+	struct fsl_mc_resource resource;
+};
+
+#define to_fsl_mc_irq(_mc_resource) \
+	container_of(_mc_resource, struct fsl_mc_device_irq, resource)
+
+/**
  * Bit masks for a MC object device (struct fsl_mc_device) flags
  */
 #define FSL_MC_IS_DPRC	0x0001
@@ -124,6 +143,7 @@ struct fsl_mc_resource {
  * NULL if none.
  * @obj_desc: MC description of the DPAA device
  * @regions: pointer to array of MMIO region entries
+ * @irqs: pointer to array of pointers to interrupts allocated to this device
  * @resource: generic resource associated with this MC object device, if any.
  *
  * Generic device object for MC object devices that are "attached" to a
@@ -155,6 +175,7 @@ struct fsl_mc_device {
 	struct fsl_mc_io *mc_io;
 	struct dprc_obj_desc obj_desc;
 	struct resource *regions;
+	struct fsl_mc_device_irq **irqs;
 	struct fsl_mc_resource *resource;
 };

@@ -196,6 +217,10 @@ int __must_check fsl_mc_object_allocate(struct fsl_mc_device *mc_dev,

 void fsl_mc_object_free(struct fsl_mc_device *mc_adev);

+int __must_check fsl_mc_allocate_irqs(struct fsl_mc_device *mc_dev);
+
+void fsl_mc_free_irqs(struct fsl_mc_device *mc_dev);
+
 extern struct bus_type fsl_mc_bus_type;

 #endif /* _FSL_MC_H_ */
--
2.3.3



More information about the devel mailing list