[PATCH v2 7/7] staging: fsl-mc: Use DPMCP IRQ and completion var to wait for MC

[J. German Rivera]

- Refactored fsl_mc_io object to have a DPMCP object attached to it
- Created DPMCP object for DPRC's built-in portal, so that waiting
  on MC command completions for MC commands sent on the DPRC's built-in
  portal can be done using a DPMCP interrupt and a Linux completion
  variable.  For most cases, mc_send_command() will wait on this
  completion variable, instead of doing polling. This completion
  variable will be signaled from the DPMCP IRQ handler.

Signed-off-by: J. German Rivera <German.Rivera@xxxxxxxxxxxxx>
Reviewed-by: Stuart Yoder <stuart.yoder@xxxxxxxxxxxxx>
---
Changes in v2:
- Use msecs_to_jiffies() instead of HZ in timeout-related expression

 drivers/staging/fsl-mc/bus/dprc-driver.c    | 180 ++++++++++--
 drivers/staging/fsl-mc/bus/mc-allocator.c   | 107 +++----
 drivers/staging/fsl-mc/bus/mc-bus.c         |  40 ++-
 drivers/staging/fsl-mc/bus/mc-sys.c         | 420 +++++++++++++++++++++++++---
 drivers/staging/fsl-mc/include/mc-private.h |   6 +-
 drivers/staging/fsl-mc/include/mc-sys.h     |  37 ++-
 6 files changed, 674 insertions(+), 116 deletions(-)

diff --git a/drivers/staging/fsl-mc/bus/dprc-driver.c b/drivers/staging/fsl-mc/bus/dprc-driver.c
index 5e24f46..db1296a 100644
--- a/drivers/staging/fsl-mc/bus/dprc-driver.c
+++ b/drivers/staging/fsl-mc/bus/dprc-driver.c
@@ -15,6 +15,7 @@
 #include <linux/slab.h>
 #include <linux/interrupt.h>
 #include "dprc-cmd.h"
+#include "dpmcp.h"

 struct dprc_child_objs {
 	int child_count;
@@ -323,7 +324,6 @@ 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);
-	struct fsl_mc *mc = dev_get_drvdata(fsl_mc_bus_type.dev_root->parent);

 	dprc_init_all_resource_pools(mc_bus_dev);

@@ -336,7 +336,7 @@ static int dprc_scan_container(struct fsl_mc_device *mc_bus_dev)
 	if (error < 0)
 		return error;

-	if (mc->gic_supported && !mc_bus->irq_resources) {
+	if (fsl_mc_interrupts_supported() && !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)
@@ -373,7 +373,8 @@ static irqreturn_t dprc_irq0_handler_thread(int irq_num, void *arg)
 	struct fsl_mc_io *mc_io = mc_dev->mc_io;
 	int irq_index = 0;

-	dev_dbg(dev, "DPRC IRQ %d\n", irq_num);
+	dev_dbg(dev, "DPRC IRQ %d triggered on CPU %u\n",
+		irq_num, smp_processor_id());
 	if (WARN_ON(!(mc_dev->flags & FSL_MC_IS_DPRC)))
 		return IRQ_HANDLED;

@@ -445,7 +446,8 @@ static int disable_dprc_irqs(struct fsl_mc_device *mc_dev)
 		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);
+				"Disabling DPRC IRQ %d failed: dprc_set_irq_enable() failed: %d\n",
+				i, error);

 			return error;
 		}
@@ -456,7 +458,8 @@ static int disable_dprc_irqs(struct fsl_mc_device *mc_dev)
 		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);
+				"Disabling DPRC IRQ %d failed: dprc_set_irq_mask() failed: %d\n",
+				i, error);

 			return error;
 		}
@@ -468,8 +471,9 @@ static int disable_dprc_irqs(struct fsl_mc_device *mc_dev)
 					      ~0x0U);
 		if (error < 0) {
 			dev_err(&mc_dev->dev,
-				"dprc_clear_irq_status() failed: %d\n",
-				error);
+				"Disabling DPRC IRQ %d failed: dprc_clear_irq_status() failed: %d\n",
+				i, error);
+
 			return error;
 		}
 	}
@@ -566,7 +570,8 @@ static int enable_dprc_irqs(struct fsl_mc_device *mc_dev)
 					  ~0x0u);
 		if (error < 0) {
 			dev_err(&mc_dev->dev,
-				"dprc_set_irq_mask() failed: %d\n", error);
+				"Enabling DPRC IRQ %d failed: dprc_set_irq_mask() failed: %d\n",
+				i, error);

 			return error;
 		}
@@ -579,7 +584,8 @@ static int enable_dprc_irqs(struct fsl_mc_device *mc_dev)
 					    i, 1);
 		if (error < 0) {
 			dev_err(&mc_dev->dev,
-				"dprc_set_irq_enable() failed: %d\n", error);
+				"Enabling DPRC IRQ %d failed: dprc_set_irq_enable() failed: %d\n",
+				i, error);

 			return error;
 		}
@@ -618,6 +624,95 @@ error_free_irqs:
 	return error;
 }

+/*
+ * Creates a DPMCP for a DPRC's built-in MC portal
+ */
+static int dprc_create_dpmcp(struct fsl_mc_device *dprc_dev)
+{
+	int error;
+	struct dpmcp_cfg dpmcp_cfg;
+	uint16_t dpmcp_handle;
+	struct dprc_res_req res_req;
+	struct dpmcp_attr dpmcp_attr;
+	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(dprc_dev);
+
+	dpmcp_cfg.portal_id = mc_bus->dprc_attr.portal_id;
+	error = dpmcp_create(dprc_dev->mc_io, &dpmcp_cfg, &dpmcp_handle);
+	if (error < 0) {
+		dev_err(&dprc_dev->dev, "dpmcp_create() failed: %d\n",
+			error);
+		return error;
+	}
+
+	/*
+	 * Set the state of the newly created DPMCP object to be "plugged":
+	 */
+
+	error = dpmcp_get_attributes(dprc_dev->mc_io, dpmcp_handle,
+				     &dpmcp_attr);
+	if (error < 0) {
+		dev_err(&dprc_dev->dev, "dpmcp_get_attributes() failed: %d\n",
+			error);
+		goto error_destroy_dpmcp;
+	}
+
+	if (WARN_ON(dpmcp_attr.id != mc_bus->dprc_attr.portal_id)) {
+		error = -EINVAL;
+		goto error_destroy_dpmcp;
+	}
+
+	strcpy(res_req.type, "dpmcp");
+	res_req.num = 1;
+	res_req.options =
+			(DPRC_RES_REQ_OPT_EXPLICIT | DPRC_RES_REQ_OPT_PLUGGED);
+	res_req.id_base_align = dpmcp_attr.id;
+
+	error = dprc_assign(dprc_dev->mc_io,
+			    dprc_dev->mc_handle,
+			    dprc_dev->obj_desc.id,
+			    &res_req);
+
+	if (error < 0) {
+		dev_err(&dprc_dev->dev, "dprc_assign() failed: %d\n", error);
+		goto error_destroy_dpmcp;
+	}
+
+	(void)dpmcp_close(dprc_dev->mc_io, dpmcp_handle);
+	return 0;
+
+error_destroy_dpmcp:
+	(void)dpmcp_destroy(dprc_dev->mc_io, dpmcp_handle);
+	return error;
+}
+
+/*
+ * Destroys the DPMCP for a DPRC's built-in MC portal
+ */
+static void dprc_destroy_dpmcp(struct fsl_mc_device *dprc_dev)
+{
+	int error;
+	uint16_t dpmcp_handle;
+	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(dprc_dev);
+
+	if (WARN_ON(!dprc_dev->mc_io || dprc_dev->mc_io->dpmcp_dev))
+		return;
+
+	error = dpmcp_open(dprc_dev->mc_io, mc_bus->dprc_attr.portal_id,
+			   &dpmcp_handle);
+	if (error < 0) {
+		dev_err(&dprc_dev->dev, "dpmcp_open() failed: %d\n",
+			error);
+		return;
+	}
+
+	error = dpmcp_destroy(dprc_dev->mc_io, dpmcp_handle);
+	if (error < 0) {
+		dev_err(&dprc_dev->dev, "dpmcp_destroy() failed: %d\n",
+			error);
+		return;
+	}
+}
+
 /**
  * dprc_probe - callback invoked when a DPRC is being bound to this driver
  *
@@ -633,7 +728,7 @@ static int dprc_probe(struct fsl_mc_device *mc_dev)
 	int error;
 	size_t region_size;
 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
-	struct fsl_mc *mc = dev_get_drvdata(fsl_mc_bus_type.dev_root->parent);
+	bool mc_io_created = false;

 	if (WARN_ON(strcmp(mc_dev->obj_desc.type, "dprc") != 0))
 		return -EINVAL;
@@ -654,6 +749,8 @@ static int dprc_probe(struct fsl_mc_device *mc_dev)
 					 NULL, 0, &mc_dev->mc_io);
 		if (error < 0)
 			return error;
+
+		mc_io_created = true;
 	}

 	error = dprc_open(mc_dev->mc_io, mc_dev->obj_desc.id,
@@ -663,16 +760,55 @@ static int dprc_probe(struct fsl_mc_device *mc_dev)
 		goto error_cleanup_mc_io;
 	}

+	error = dprc_get_attributes(mc_dev->mc_io, mc_dev->mc_handle,
+				    &mc_bus->dprc_attr);
+	if (error < 0) {
+		dev_err(&mc_dev->dev, "dprc_get_attributes() failed: %d\n",
+			error);
+		goto error_cleanup_open;
+	}
+
+	if (fsl_mc_interrupts_supported()) {
+		/*
+		 * Create DPMCP for the DPRC's built-in portal:
+		 */
+		error = dprc_create_dpmcp(mc_dev);
+		if (error < 0)
+			goto error_cleanup_open;
+	}
+
 	mutex_init(&mc_bus->scan_mutex);

 	/*
-	 * Discover MC objects in DPRC object:
+	 * Discover MC objects in the DPRC object:
 	 */
 	error = dprc_scan_container(mc_dev);
 	if (error < 0)
-		goto error_cleanup_open;
+		goto error_destroy_dpmcp;
+
+	if (fsl_mc_interrupts_supported()) {
+		/*
+		 * The fsl_mc_device object associated with the DPMCP object
+		 * created above was created as part of the
+		 * dprc_scan_container() call above:
+		 */
+		if (WARN_ON(!mc_dev->mc_io->dpmcp_dev)) {
+			error = -EINVAL;
+			goto error_cleanup_dprc_scan;
+		}
+
+		/*
+		 * Configure interrupt for the DPMCP object associated with the
+		 * DPRC object's built-in portal:
+		 *
+		 * NOTE: We have to do this after calling dprc_scan_container(),
+		 * since dprc_scan_container() will populate the IRQ pool for
+		 * this DPRC.
+		 */
+		error = fsl_mc_io_setup_dpmcp_irq(mc_dev->mc_io);
+		if (error < 0)
+			goto error_cleanup_dprc_scan;

-	if (mc->gic_supported) {
 		/*
 		 * Configure interrupts for the DPRC object associated with
 		 * this MC bus:
@@ -686,15 +822,22 @@ static int dprc_probe(struct fsl_mc_device *mc_dev)
 	return 0;

 error_cleanup_dprc_scan:
+	fsl_mc_io_unset_dpmcp(mc_dev->mc_io);
 	device_for_each_child(&mc_dev->dev, NULL, __fsl_mc_device_remove);
-	if (mc->gic_supported)
+	if (fsl_mc_interrupts_supported())
 		fsl_mc_cleanup_irq_pool(mc_bus);

+error_destroy_dpmcp:
+	dprc_destroy_dpmcp(mc_dev);
+
 error_cleanup_open:
 	(void)dprc_close(mc_dev->mc_io, mc_dev->mc_handle);

 error_cleanup_mc_io:
-	fsl_destroy_mc_io(mc_dev->mc_io);
+	if (mc_io_created) {
+		fsl_destroy_mc_io(mc_dev->mc_io);
+		mc_dev->mc_io = NULL;
+	}
 	return error;
 }

@@ -721,7 +864,6 @@ static int dprc_remove(struct fsl_mc_device *mc_dev)
 {
 	int error;
 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
-	struct fsl_mc *mc = dev_get_drvdata(fsl_mc_bus_type.dev_root->parent);

 	if (WARN_ON(strcmp(mc_dev->obj_desc.type, "dprc") != 0))
 		return -EINVAL;
@@ -731,15 +873,17 @@ static int dprc_remove(struct fsl_mc_device *mc_dev)
 	if (WARN_ON(!mc_bus->irq_resources))
 		return -EINVAL;

-	if (mc->gic_supported)
+	if (fsl_mc_interrupts_supported())
 		dprc_teardown_irqs(mc_dev);

+	fsl_mc_io_unset_dpmcp(mc_dev->mc_io);
 	device_for_each_child(&mc_dev->dev, NULL, __fsl_mc_device_remove);
+	dprc_destroy_dpmcp(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);

-	if (mc->gic_supported)
+	if (fsl_mc_interrupts_supported())
 		fsl_mc_cleanup_irq_pool(mc_bus);

 	dev_info(&mc_dev->dev, "DPRC device unbound from driver");
diff --git a/drivers/staging/fsl-mc/bus/mc-allocator.c b/drivers/staging/fsl-mc/bus/mc-allocator.c
index 3bdfefb..15409ff 100644
--- a/drivers/staging/fsl-mc/bus/mc-allocator.c
+++ b/drivers/staging/fsl-mc/bus/mc-allocator.c
@@ -109,7 +109,7 @@ static int __must_check fsl_mc_resource_pool_remove_device(struct fsl_mc_device
 		goto out;

 	resource = mc_dev->resource;
-	if (WARN_ON(resource->data != mc_dev))
+	if (WARN_ON(!resource || resource->data != mc_dev))
 		goto out;

 	mc_bus_dev = to_fsl_mc_device(mc_dev->dev.parent);
@@ -281,7 +281,7 @@ int __must_check fsl_mc_portal_allocate(struct fsl_mc_device *mc_dev,
 	struct fsl_mc_bus *mc_bus;
 	phys_addr_t mc_portal_phys_addr;
 	size_t mc_portal_size;
-	struct fsl_mc_device *mc_adev;
+	struct fsl_mc_device *dpmcp_dev;
 	int error = -EINVAL;
 	struct fsl_mc_resource *resource = NULL;
 	struct fsl_mc_io *mc_io = NULL;
@@ -301,23 +301,24 @@ int __must_check fsl_mc_portal_allocate(struct fsl_mc_device *mc_dev,
 	if (error < 0)
 		return error;

-	mc_adev = resource->data;
-	if (WARN_ON(!mc_adev))
+	dpmcp_dev = resource->data;
+	if (WARN_ON(!dpmcp_dev ||
+		    strcmp(dpmcp_dev->obj_desc.type, "dpmcp") != 0))
 		goto error_cleanup_resource;

-	if (WARN_ON(mc_adev->obj_desc.region_count == 0))
+	if (WARN_ON(dpmcp_dev->obj_desc.region_count == 0))
 		goto error_cleanup_resource;

-	mc_portal_phys_addr = mc_adev->regions[0].start;
-	mc_portal_size = mc_adev->regions[0].end -
-			 mc_adev->regions[0].start + 1;
+	mc_portal_phys_addr = dpmcp_dev->regions[0].start;
+	mc_portal_size = dpmcp_dev->regions[0].end -
+			 dpmcp_dev->regions[0].start + 1;

 	if (WARN_ON(mc_portal_size != mc_bus_dev->mc_io->portal_size))
 		goto error_cleanup_resource;

 	error = fsl_create_mc_io(&mc_bus_dev->dev,
 				 mc_portal_phys_addr,
-				 mc_portal_size, resource,
+				 mc_portal_size, dpmcp_dev,
 				 mc_io_flags, &mc_io);
 	if (error < 0)
 		goto error_cleanup_resource;
@@ -339,12 +340,26 @@ EXPORT_SYMBOL_GPL(fsl_mc_portal_allocate);
  */
 void fsl_mc_portal_free(struct fsl_mc_io *mc_io)
 {
+	struct fsl_mc_device *dpmcp_dev;
 	struct fsl_mc_resource *resource;

-	resource = mc_io->resource;
-	if (WARN_ON(resource->type != FSL_MC_POOL_DPMCP))
+	/*
+	 * Every mc_io obtained by calling fsl_mc_portal_allocate() is supposed
+	 * to have a DPMCP object associated with.
+	 */
+	dpmcp_dev = mc_io->dpmcp_dev;
+	if (WARN_ON(!dpmcp_dev))
+		return;
+	if (WARN_ON(strcmp(dpmcp_dev->obj_desc.type, "dpmcp") != 0))
+		return;
+	if (WARN_ON(dpmcp_dev->mc_io != mc_io))
+		return;
+
+	resource = dpmcp_dev->resource;
+	if (WARN_ON(!resource || resource->type != FSL_MC_POOL_DPMCP))
 		return;
-	if (WARN_ON(!resource->data))
+
+	if (WARN_ON(resource->data != dpmcp_dev))
 		return;

 	fsl_destroy_mc_io(mc_io);
@@ -360,31 +375,14 @@ EXPORT_SYMBOL_GPL(fsl_mc_portal_free);
 int fsl_mc_portal_reset(struct fsl_mc_io *mc_io)
 {
 	int error;
-	uint16_t token;
-	struct fsl_mc_resource *resource = mc_io->resource;
-	struct fsl_mc_device *mc_dev = resource->data;
-
-	if (WARN_ON(resource->type != FSL_MC_POOL_DPMCP))
-		return -EINVAL;
+	struct fsl_mc_device *dpmcp_dev = mc_io->dpmcp_dev;

-	if (WARN_ON(!mc_dev))
+	if (WARN_ON(!dpmcp_dev))
 		return -EINVAL;

-	error = dpmcp_open(mc_io, mc_dev->obj_desc.id, &token);
+	error = dpmcp_reset(mc_io, dpmcp_dev->mc_handle);
 	if (error < 0) {
-		dev_err(&mc_dev->dev, "dpmcp_open() failed: %d\n", error);
-		return error;
-	}
-
-	error = dpmcp_reset(mc_io, token);
-	if (error < 0) {
-		dev_err(&mc_dev->dev, "dpmcp_reset() failed: %d\n", error);
-		return error;
-	}
-
-	error = dpmcp_close(mc_io, token);
-	if (error < 0) {
-		dev_err(&mc_dev->dev, "dpmcp_close() failed: %d\n", error);
+		dev_err(&dpmcp_dev->dev, "dpmcp_reset() failed: %d\n", error);
 		return error;
 	}

@@ -599,13 +597,28 @@ static int fsl_mc_allocator_probe(struct fsl_mc_device *mc_dev)
 		goto error;

 	mc_bus = to_fsl_mc_bus(mc_bus_dev);
-	error = object_type_to_pool_type(mc_dev->obj_desc.type, &pool_type);
-	if (error < 0)
-		goto error;

-	error = fsl_mc_resource_pool_add_device(mc_bus, pool_type, mc_dev);
-	if (error < 0)
-		goto error;
+	/*
+	 * If mc_dev is the DPMCP object for the parent DPRC's built-in
+	 * portal, we don't add this DPMCP to the DPMCP object pool,
+	 * but instead allocate it directly to the parent DPRC (mc_bus_dev):
+	 */
+	if (strcmp(mc_dev->obj_desc.type, "dpmcp") == 0 &&
+	    mc_dev->obj_desc.id == mc_bus->dprc_attr.portal_id) {
+		error = fsl_mc_io_set_dpmcp(mc_bus_dev->mc_io, mc_dev);
+		if (error < 0)
+			goto error;
+	} else {
+		error = object_type_to_pool_type(mc_dev->obj_desc.type,
+						 &pool_type);
+		if (error < 0)
+			goto error;
+
+		error = fsl_mc_resource_pool_add_device(mc_bus, pool_type,
+							mc_dev);
+		if (error < 0)
+			goto error;
+	}

 	dev_dbg(&mc_dev->dev,
 		"Allocatable MC object device bound to fsl_mc_allocator driver");
@@ -621,20 +634,20 @@ error:
  */
 static int fsl_mc_allocator_remove(struct fsl_mc_device *mc_dev)
 {
-	int error = -EINVAL;
+	int error;

 	if (WARN_ON(!FSL_MC_IS_ALLOCATABLE(mc_dev->obj_desc.type)))
-		goto out;
+		return -EINVAL;

-	error = fsl_mc_resource_pool_remove_device(mc_dev);
-	if (error < 0)
-		goto out;
+	if (mc_dev->resource) {
+		error = fsl_mc_resource_pool_remove_device(mc_dev);
+		if (error < 0)
+			return error;
+	}

 	dev_dbg(&mc_dev->dev,
 		"Allocatable MC object device unbound from fsl_mc_allocator driver");
-	error = 0;
-out:
-	return error;
+	return 0;
 }

 static const struct fsl_mc_device_match_id match_id_table[] = {
diff --git a/drivers/staging/fsl-mc/bus/mc-bus.c b/drivers/staging/fsl-mc/bus/mc-bus.c
index 36116d7..6e25fd9 100644
--- a/drivers/staging/fsl-mc/bus/mc-bus.c
+++ b/drivers/staging/fsl-mc/bus/mc-bus.c
@@ -601,6 +601,11 @@ void fsl_mc_device_remove(struct fsl_mc_device *mc_dev)

 		if (&mc_dev->dev == fsl_mc_bus_type.dev_root)
 			fsl_mc_bus_type.dev_root = NULL;
+	} else if (strcmp(mc_dev->obj_desc.type, "dpmcp") == 0) {
+		if (mc_dev->mc_io) {
+			fsl_destroy_mc_io(mc_dev->mc_io);
+			mc_dev->mc_io = NULL;
+		}
 	}

 	kfree(mc_dev->driver_override);
@@ -680,19 +685,23 @@ static void mc_bus_msi_domain_write_msg(struct irq_data *irq_data,
 	struct fsl_mc_device_irq *irq_res =
 		&mc_bus->irq_resources[msi_entry->msi_attrib.entry_nr];

+	/*
+	 * NOTE: This function is invoked with interrupts disabled
+	 */
+
 	if (irq_res->irq_number == irq_data->irq) {
 		/*
 		 * write msg->address_hi/lo to irq_resource
 		 */
 		irq_res->msi_paddr =
 			((u64)msg->address_hi << 32) | msg->address_lo;
+
 		irq_res->msi_value = msg->data;

 		/*
-		 * NOTE: We cannot do the actual programming of the MSI
-		 * in the MC, in this function, as the object-independent
-		 * way of programming MSIs for MC objects is not reliable
-		 * if objects are being added/removed dynamically.
+		 * NOTE: We cannot do the actual programming of the MSI,
+		 * in the MC, here, because calling dprc_obj_set_irq()
+		 * is not reliable, as object indexes may change under us.
 		 */
 	}
 }
@@ -848,7 +857,12 @@ int __must_check fsl_mc_populate_irq_pool(struct fsl_mc_bus *mc_bus,
 		dev_err(&mc_bus_dev->dev, "Failed to allocate IRQs\n");
 		goto cleanup_msi_entries;
 	}
+#endif

+	/*
+	 * FIXME: Enable this code when the GIC-ITS MC support patch is merged
+	 */
+#ifdef GIC_ITS_MC_SUPPORT
 	for_each_msi_entry(msi_entry, &mc_bus_dev->dev) {
 		u32 irq_num = msi_entry->irq;

@@ -1140,7 +1154,14 @@ error_cleanup_mc_io:
 	fsl_destroy_mc_io(mc_io);

 error_cleanup_irq_domain:
-	irq_domain_remove(mc->irq_domain);
+	/*
+	 * FIXME: Enable this code when the GIC-ITS MC support patch is merged
+	 */
+#ifdef GIC_ITS_MC_SUPPORT
+	if (mc->gic_supported)
+		irq_domain_remove(mc->irq_domain);
+#endif
+
 	return error;
 }

@@ -1155,7 +1176,14 @@ 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);
+	/*
+	 * FIXME: Enable this code when the GIC-ITS MC support patch is merged
+	 */
+#ifdef GIC_ITS_MC_SUPPORT
+	if (mc->gic_supported)
+		irq_domain_remove(mc->irq_domain);
+#endif
+
 	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/bus/mc-sys.c b/drivers/staging/fsl-mc/bus/mc-sys.c
index 2b3d18c..1af35a1 100644
--- a/drivers/staging/fsl-mc/bus/mc-sys.c
+++ b/drivers/staging/fsl-mc/bus/mc-sys.c
@@ -34,10 +34,13 @@

 #include "../include/mc-sys.h"
 #include "../include/mc-cmd.h"
+#include "../include/mc.h"
 #include <linux/delay.h>
 #include <linux/slab.h>
 #include <linux/ioport.h>
 #include <linux/device.h>
+#include <linux/interrupt.h>
+#include "dpmcp.h"

 /**
  * Timeout in milliseconds to wait for the completion of an MC command
@@ -55,6 +58,230 @@
 	((uint16_t)mc_dec((_hdr), MC_CMD_HDR_CMDID_O, MC_CMD_HDR_CMDID_S))

 /**
+ * dpmcp_irq0_handler - Regular ISR for DPMCP interrupt 0
+ *
+ * @irq: IRQ number of the interrupt being handled
+ * @arg: Pointer to device structure
+ */
+static irqreturn_t dpmcp_irq0_handler(int irq_num, void *arg)
+{
+	struct device *dev = (struct device *)arg;
+	struct fsl_mc_device *dpmcp_dev = to_fsl_mc_device(dev);
+
+	dev_dbg(dev, "DPMCP IRQ %d triggered on CPU %u\n", irq_num,
+		smp_processor_id());
+
+	if (WARN_ON(dpmcp_dev->irqs[0]->irq_number != (uint32_t)irq_num))
+		goto out;
+
+	if (WARN_ON(!dpmcp_dev->mc_io))
+		goto out;
+
+	/*
+	 * NOTE: We cannot invoke MC flib function here
+	 */
+
+	complete(&dpmcp_dev->mc_io->mc_command_done_completion);
+out:
+	return IRQ_HANDLED;
+}
+
+/*
+ * Disable and clear interrupts for a given DPMCP object
+ */
+static int disable_dpmcp_irq(struct fsl_mc_device *dpmcp_dev)
+{
+	int error;
+
+	/*
+	 * Disable generation of the DPMCP interrupt:
+	 */
+	error = dpmcp_set_irq_enable(dpmcp_dev->mc_io,
+				     dpmcp_dev->mc_handle,
+				     DPMCP_IRQ_INDEX, 0);
+	if (error < 0) {
+		dev_err(&dpmcp_dev->dev,
+			"dpmcp_set_irq_enable() failed: %d\n", error);
+
+		return error;
+	}
+
+	/*
+	 * Disable all DPMCP interrupt causes:
+	 */
+	error = dpmcp_set_irq_mask(dpmcp_dev->mc_io, dpmcp_dev->mc_handle,
+				   DPMCP_IRQ_INDEX, 0x0);
+	if (error < 0) {
+		dev_err(&dpmcp_dev->dev,
+			"dpmcp_set_irq_mask() failed: %d\n", error);
+
+		return error;
+	}
+
+	/*
+	 * Clear any leftover interrupts:
+	 */
+	error = dpmcp_clear_irq_status(dpmcp_dev->mc_io, dpmcp_dev->mc_handle,
+				       DPMCP_IRQ_INDEX, ~0x0U);
+	if (error < 0) {
+		dev_err(&dpmcp_dev->dev,
+			"dpmcp_clear_irq_status() failed: %d\n",
+			error);
+		return error;
+	}
+
+	return 0;
+}
+
+static void unregister_dpmcp_irq_handler(struct fsl_mc_device *dpmcp_dev)
+{
+	struct fsl_mc_device_irq *irq = dpmcp_dev->irqs[DPMCP_IRQ_INDEX];
+
+	devm_free_irq(&dpmcp_dev->dev, irq->irq_number, &dpmcp_dev->dev);
+}
+
+static int register_dpmcp_irq_handler(struct fsl_mc_device *dpmcp_dev)
+{
+	int error;
+	struct fsl_mc_device_irq *irq = dpmcp_dev->irqs[DPMCP_IRQ_INDEX];
+
+	error = devm_request_irq(&dpmcp_dev->dev,
+				 irq->irq_number,
+				 dpmcp_irq0_handler,
+				 IRQF_NO_SUSPEND | IRQF_ONESHOT,
+				 "FSL MC DPMCP irq0",
+				 &dpmcp_dev->dev);
+	if (error < 0) {
+		dev_err(&dpmcp_dev->dev,
+			"devm_request_irq() failed: %d\n",
+			error);
+		return error;
+	}
+
+	error = dpmcp_set_irq(dpmcp_dev->mc_io,
+			      dpmcp_dev->mc_handle,
+			      DPMCP_IRQ_INDEX,
+			      irq->msi_paddr,
+			      irq->msi_value,
+			      irq->irq_number);
+	if (error < 0) {
+		dev_err(&dpmcp_dev->dev,
+			"dpmcp_set_irq() failed: %d\n", error);
+		goto error_unregister_irq_handler;
+	}
+
+	return 0;
+
+error_unregister_irq_handler:
+	devm_free_irq(&dpmcp_dev->dev, irq->irq_number, &dpmcp_dev->dev);
+	return error;
+}
+
+static int enable_dpmcp_irq(struct fsl_mc_device *dpmcp_dev)
+{
+	int error;
+
+	/*
+	 * Enable MC command completion event to trigger DPMCP interrupt:
+	 */
+	error = dpmcp_set_irq_mask(dpmcp_dev->mc_io,
+				   dpmcp_dev->mc_handle,
+				   DPMCP_IRQ_INDEX,
+				   DPMCP_IRQ_EVENT_CMD_DONE);
+	if (error < 0) {
+		dev_err(&dpmcp_dev->dev,
+			"dpmcp_set_irq_mask() failed: %d\n", error);
+
+		return error;
+	}
+
+	/*
+	 * Enable generation of the interrupt:
+	 */
+	error = dpmcp_set_irq_enable(dpmcp_dev->mc_io,
+				     dpmcp_dev->mc_handle,
+				     DPMCP_IRQ_INDEX, 1);
+	if (error < 0) {
+		dev_err(&dpmcp_dev->dev,
+			"dpmcp_set_irq_enable() failed: %d\n", error);
+
+		return error;
+	}
+
+	return 0;
+}
+
+/*
+ * Setup MC command completion interrupt for the DPMCP device associated with a
+ * given fsl_mc_io object
+ */
+int fsl_mc_io_setup_dpmcp_irq(struct fsl_mc_io *mc_io)
+{
+	int error;
+	struct fsl_mc_device *dpmcp_dev = mc_io->dpmcp_dev;
+
+	if (WARN_ON(!dpmcp_dev))
+		return -EINVAL;
+
+	if (WARN_ON(!fsl_mc_interrupts_supported()))
+		return -EINVAL;
+
+	if (WARN_ON(dpmcp_dev->obj_desc.irq_count != 1))
+		return -EINVAL;
+
+	if (WARN_ON(!dpmcp_dev->mc_io))
+		return -EINVAL;
+
+	error = fsl_mc_allocate_irqs(dpmcp_dev);
+	if (error < 0)
+		return error;
+
+	error = disable_dpmcp_irq(dpmcp_dev);
+	if (error < 0)
+		goto error_free_irqs;
+
+	error = register_dpmcp_irq_handler(dpmcp_dev);
+	if (error < 0)
+		goto error_free_irqs;
+
+	error = enable_dpmcp_irq(dpmcp_dev);
+	if (error < 0)
+		goto error_unregister_irq_handler;
+
+	mc_io->mc_command_done_irq_armed = true;
+	return 0;
+
+error_unregister_irq_handler:
+	unregister_dpmcp_irq_handler(dpmcp_dev);
+
+error_free_irqs:
+	fsl_mc_free_irqs(dpmcp_dev);
+	return error;
+}
+EXPORT_SYMBOL_GPL(fsl_mc_io_setup_dpmcp_irq);
+
+/*
+ * Tear down interrupts for the DPMCP device associated with a given fsl_mc_io
+ * object
+ */
+static void teardown_dpmcp_irq(struct fsl_mc_io *mc_io)
+{
+	struct fsl_mc_device *dpmcp_dev = mc_io->dpmcp_dev;
+
+	if (WARN_ON(!dpmcp_dev))
+		return;
+	if (WARN_ON(!fsl_mc_interrupts_supported()))
+		return;
+	if (WARN_ON(!dpmcp_dev->irqs))
+		return;
+
+	mc_io->mc_command_done_irq_armed = false;
+	(void)disable_dpmcp_irq(dpmcp_dev);
+	unregister_dpmcp_irq_handler(dpmcp_dev);
+	fsl_mc_free_irqs(dpmcp_dev);
+}
+
+/**
  * Creates an MC I/O object
  *
  * @dev: device to be associated with the MC I/O object
@@ -70,9 +297,10 @@
 int __must_check fsl_create_mc_io(struct device *dev,
 				  phys_addr_t mc_portal_phys_addr,
 				  uint32_t mc_portal_size,
-				  struct fsl_mc_resource *resource,
+				  struct fsl_mc_device *dpmcp_dev,
 				  uint32_t flags, struct fsl_mc_io **new_mc_io)
 {
+	int error;
 	struct fsl_mc_io *mc_io;
 	void __iomem *mc_portal_virt_addr;
 	struct resource *res;
@@ -85,11 +313,13 @@ int __must_check fsl_create_mc_io(struct device *dev,
 	mc_io->flags = flags;
 	mc_io->portal_phys_addr = mc_portal_phys_addr;
 	mc_io->portal_size = mc_portal_size;
-	mc_io->resource = resource;
-	if (flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)
+	mc_io->mc_command_done_irq_armed = false;
+	if (flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL) {
 		spin_lock_init(&mc_io->spinlock);
-	else
+	} else {
 		mutex_init(&mc_io->mutex);
+		init_completion(&mc_io->mc_command_done_completion);
+	}

 	res = devm_request_mem_region(dev,
 				      mc_portal_phys_addr,
@@ -113,8 +343,26 @@ int __must_check fsl_create_mc_io(struct device *dev,
 	}

 	mc_io->portal_virt_addr = mc_portal_virt_addr;
+	if (dpmcp_dev) {
+		error = fsl_mc_io_set_dpmcp(mc_io, dpmcp_dev);
+		if (error < 0)
+			goto error_destroy_mc_io;
+
+		if (!(flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL) &&
+		    fsl_mc_interrupts_supported()) {
+			error = fsl_mc_io_setup_dpmcp_irq(mc_io);
+			if (error < 0)
+				goto error_destroy_mc_io;
+		}
+	}
+
 	*new_mc_io = mc_io;
 	return 0;
+
+error_destroy_mc_io:
+	fsl_destroy_mc_io(mc_io);
+	return error;
+
 }
 EXPORT_SYMBOL_GPL(fsl_create_mc_io);

@@ -125,6 +373,11 @@ EXPORT_SYMBOL_GPL(fsl_create_mc_io);
  */
 void fsl_destroy_mc_io(struct fsl_mc_io *mc_io)
 {
+	struct fsl_mc_device *dpmcp_dev = mc_io->dpmcp_dev;
+
+	if (dpmcp_dev)
+		fsl_mc_io_unset_dpmcp(mc_io);
+
 	devm_iounmap(mc_io->dev, mc_io->portal_virt_addr);
 	devm_release_mem_region(mc_io->dev,
 				mc_io->portal_phys_addr,
@@ -135,6 +388,60 @@ void fsl_destroy_mc_io(struct fsl_mc_io *mc_io)
 }
 EXPORT_SYMBOL_GPL(fsl_destroy_mc_io);

+int fsl_mc_io_set_dpmcp(struct fsl_mc_io *mc_io,
+			struct fsl_mc_device *dpmcp_dev)
+{
+	int error;
+
+	if (WARN_ON(!dpmcp_dev))
+		return -EINVAL;
+
+	if (WARN_ON(mc_io->dpmcp_dev))
+		return -EINVAL;
+
+	if (WARN_ON(dpmcp_dev->mc_io))
+		return -EINVAL;
+
+	if (!(mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)) {
+		error = dpmcp_open(mc_io, dpmcp_dev->obj_desc.id,
+				   &dpmcp_dev->mc_handle);
+		if (error < 0)
+			return error;
+	}
+
+	mc_io->dpmcp_dev = dpmcp_dev;
+	dpmcp_dev->mc_io = mc_io;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(fsl_mc_io_set_dpmcp);
+
+void fsl_mc_io_unset_dpmcp(struct fsl_mc_io *mc_io)
+{
+	int error;
+	struct fsl_mc_device *dpmcp_dev = mc_io->dpmcp_dev;
+
+	if (WARN_ON(!dpmcp_dev))
+		return;
+
+	if (WARN_ON(dpmcp_dev->mc_io != mc_io))
+		return;
+
+	if (!(mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)) {
+		if (dpmcp_dev->irqs)
+			teardown_dpmcp_irq(mc_io);
+
+		error = dpmcp_close(mc_io, dpmcp_dev->mc_handle);
+		if (error < 0) {
+			dev_err(&dpmcp_dev->dev, "dpmcp_close() failed: %d\n",
+				error);
+		}
+	}
+
+	mc_io->dpmcp_dev = NULL;
+	dpmcp_dev->mc_io = NULL;
+}
+EXPORT_SYMBOL_GPL(fsl_mc_io_unset_dpmcp);
+
 static int mc_status_to_error(enum mc_cmd_status status)
 {
 	static const int mc_status_to_error_map[] = {
@@ -228,46 +535,51 @@ static inline enum mc_cmd_status mc_read_response(struct mc_command __iomem *
 	return status;
 }

-/**
- * Sends an command to the MC device using the given MC I/O object
- *
- * @mc_io: MC I/O object to be used
- * @cmd: command to be sent
- *
- * Returns '0' on Success; Error code otherwise.
- */
-int mc_send_command(struct fsl_mc_io *mc_io, struct mc_command *cmd)
+static int mc_completion_wait(struct fsl_mc_io *mc_io, struct mc_command *cmd,
+			      enum mc_cmd_status *mc_status)
 {
-	int error;
 	enum mc_cmd_status status;
-	unsigned long jiffies_until_timeout =
-		jiffies + msecs_to_jiffies(MC_CMD_COMPLETION_TIMEOUT_MS);
+	unsigned long jiffies_left;
+	unsigned long timeout_jiffies =
+		msecs_to_jiffies(MC_CMD_COMPLETION_TIMEOUT_MS);

-	if (WARN_ON(in_irq()))
+	if (WARN_ON(!mc_io->dpmcp_dev))
 		return -EINVAL;

-	if (mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)
-		spin_lock(&mc_io->spinlock);
-	else
-		mutex_lock(&mc_io->mutex);
+	if (WARN_ON(mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL))
+		return -EINVAL;

-	/*
-	 * Send command to the MC hardware:
-	 */
-	mc_write_command(mc_io->portal_virt_addr, cmd);
+	if (WARN_ON(!preemptible()))
+		return -EINVAL;
+
+	for (;;) {
+		status = mc_read_response(mc_io->portal_virt_addr, cmd);
+		if (status != MC_CMD_STATUS_READY)
+			break;
+
+		jiffies_left = wait_for_completion_timeout(
+					&mc_io->mc_command_done_completion,
+					timeout_jiffies);
+		if (jiffies_left == 0)
+			return -ETIMEDOUT;
+	}
+
+	*mc_status = status;
+	return 0;
+}
+
+static int mc_polling_wait(struct fsl_mc_io *mc_io, struct mc_command *cmd,
+			   enum mc_cmd_status *mc_status)
+{
+	enum mc_cmd_status status;
+	unsigned long jiffies_until_timeout =
+		jiffies + msecs_to_jiffies(MC_CMD_COMPLETION_TIMEOUT_MS);

-	/*
-	 * Wait for response from the MC hardware:
-	 */
 	for (;;) {
 		status = mc_read_response(mc_io->portal_virt_addr, cmd);
 		if (status != MC_CMD_STATUS_READY)
 			break;

-		/*
-		 * TODO: When MC command completion interrupts are supported
-		 * call wait function here instead of usleep_range()
-		 */
 		if (preemptible()) {
 			usleep_range(MC_CMD_COMPLETION_POLLING_MIN_SLEEP_USECS,
 				     MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS);
@@ -283,11 +595,51 @@ int mc_send_command(struct fsl_mc_io *mc_io, struct mc_command *cmd)
 				 (unsigned int)
 					MC_CMD_HDR_READ_CMDID(cmd->header));

-			error = -ETIMEDOUT;
-			goto common_exit;
+			return -ETIMEDOUT;
 		}
 	}

+	*mc_status = status;
+	return 0;
+}
+
+/**
+ * Sends a command to the MC device using the given MC I/O object
+ *
+ * @mc_io: MC I/O object to be used
+ * @cmd: command to be sent
+ *
+ * Returns '0' on Success; Error code otherwise.
+ */
+int mc_send_command(struct fsl_mc_io *mc_io, struct mc_command *cmd)
+{
+	int error;
+	enum mc_cmd_status status;
+
+	if (WARN_ON(in_irq()))
+		return -EINVAL;
+
+	if (mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)
+		spin_lock(&mc_io->spinlock);
+	else
+		mutex_lock(&mc_io->mutex);
+
+	/*
+	 * Send command to the MC hardware:
+	 */
+	mc_write_command(mc_io->portal_virt_addr, cmd);
+
+	/*
+	 * Wait for response from the MC hardware:
+	 */
+	if (mc_io->mc_command_done_irq_armed)
+		error = mc_completion_wait(mc_io, cmd, &status);
+	else
+		error = mc_polling_wait(mc_io, cmd, &status);
+
+	if (error < 0)
+		goto common_exit;
+
 	if (status != MC_CMD_STATUS_OK) {
 		pr_debug("MC command failed: portal: %#llx, obj handle: %#x, command: %#x, status: %s (%#x)\n",
 			 mc_io->portal_phys_addr,
diff --git a/drivers/staging/fsl-mc/include/mc-private.h b/drivers/staging/fsl-mc/include/mc-private.h
index 0757258..90b059a 100644
--- a/drivers/staging/fsl-mc/include/mc-private.h
+++ b/drivers/staging/fsl-mc/include/mc-private.h
@@ -111,12 +111,14 @@ struct fsl_mc_resource_pool {
  * from the physical DPRC.
  * @irq_resources: Pointer to array of IRQ objects for the IRQ pool.
  * @scan_mutex: Serializes bus scanning
+ * @dprc_attr: DPRC attributes
  */
 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 */
+	struct dprc_attributes dprc_attr;
 };

 #define to_fsl_mc_bus(_mc_dev) \
@@ -134,10 +136,6 @@ int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev,
 		      const char *driver_override,
 		      unsigned int *total_irq_count);

-int dprc_lookup_object(struct fsl_mc_device *mc_bus_dev,
-		       struct fsl_mc_device *child_dev,
-		       uint32_t *child_obj_index);
-
 int __init dprc_driver_init(void);

 void __exit dprc_driver_exit(void);
diff --git a/drivers/staging/fsl-mc/include/mc-sys.h b/drivers/staging/fsl-mc/include/mc-sys.h
index 7ea12a6..fbf4b73 100644
--- a/drivers/staging/fsl-mc/include/mc-sys.h
+++ b/drivers/staging/fsl-mc/include/mc-sys.h
@@ -39,6 +39,7 @@
 #include <linux/errno.h>
 #include <linux/io.h>
 #include <linux/dma-mapping.h>
+#include <linux/completion.h>
 #include <linux/mutex.h>
 #include <linux/spinlock.h>

@@ -57,9 +58,11 @@ struct mc_command;
  * @portal_size: MC command portal size in bytes
  * @portal_phys_addr: MC command portal physical address
  * @portal_virt_addr: MC command portal virtual address
- * @resource: generic resource associated with the MC portal if
- * the MC portal came from a resource pool, or NULL if the MC portal
- * is permanently bound to a device (e.g., a DPRC)
+ * @dpmcp_dev: pointer to the DPMCP device associated with the MC portal.
+ * @mc_command_done_irq_armed: Flag indicating that the MC command done IRQ
+ * is currently armed.
+ * @mc_command_done_completion: Completion variable to be signaled when an MC
+ * command sent to the MC fw is completed.
  * @mutex: Mutex to serialize mc_send_command() calls that use the same MC
  * portal, if the fsl_mc_io object was created with the
  * FSL_MC_IO_ATOMIC_CONTEXT_PORTAL flag off. mc_send_command() calls for this
@@ -75,21 +78,41 @@ struct fsl_mc_io {
 	uint16_t portal_size;
 	phys_addr_t portal_phys_addr;
 	void __iomem *portal_virt_addr;
-	struct fsl_mc_resource *resource;
+	struct fsl_mc_device *dpmcp_dev;
 	union {
-		struct mutex mutex;	/* serializes mc_send_command() calls */
-		spinlock_t spinlock;	/* serializes mc_send_command() calls */
+		/*
+		 * These fields are only meaningful if the
+		 * FSL_MC_IO_ATOMIC_CONTEXT_PORTAL flag is not set
+		 */
+		struct {
+			struct mutex mutex; /* serializes mc_send_command() */
+			struct completion mc_command_done_completion;
+			bool mc_command_done_irq_armed;
+		};
+
+		/*
+		 * This field is only meaningful if the
+		 * FSL_MC_IO_ATOMIC_CONTEXT_PORTAL flag is set
+		 */
+		spinlock_t spinlock;	/* serializes mc_send_command() */
 	};
 };

 int __must_check fsl_create_mc_io(struct device *dev,
 				  phys_addr_t mc_portal_phys_addr,
 				  uint32_t mc_portal_size,
-				  struct fsl_mc_resource *resource,
+				  struct fsl_mc_device *dpmcp_dev,
 				  uint32_t flags, struct fsl_mc_io **new_mc_io);

 void fsl_destroy_mc_io(struct fsl_mc_io *mc_io);

+int fsl_mc_io_set_dpmcp(struct fsl_mc_io *mc_io,
+			struct fsl_mc_device *dpmcp_dev);
+
+void fsl_mc_io_unset_dpmcp(struct fsl_mc_io *mc_io);
+
+int fsl_mc_io_setup_dpmcp_irq(struct fsl_mc_io *mc_io);
+
 int mc_send_command(struct fsl_mc_io *mc_io, struct mc_command *cmd);

 #endif /* _FSL_MC_SYS_H */
--
2.3.3

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