1 files changed, 118 insertions, 72 deletions

diff --git a/drivers/bus/fsl-mc/dprc-driver.c b/drivers/bus/fsl-mc/dprc-driver.c
index 2a473c09bc33..91dc015963a8 100644
--- a/drivers/bus/fsl-mc/dprc-driver.c
+++ b/drivers/bus/fsl-mc/dprc-driver.c
@@ -3,6 +3,7 @@
  * Freescale data path resource container (DPRC) driver
  *
  * Copyright (C) 2014-2016 Freescale Semiconductor, Inc.
+ * Copyright 2019-2020 NXP
  * Author: German Rivera <German.Rivera@freescale.com>
  *
  */
@@ -80,9 +81,9 @@ static int __fsl_mc_device_remove(struct device *dev, void *data)
  * the MC by removing devices that represent MC objects that have
  * been dynamically removed in the physical DPRC.
  */
-static void dprc_remove_devices(struct fsl_mc_device *mc_bus_dev,
-				struct fsl_mc_obj_desc *obj_desc_array,
-				int num_child_objects_in_mc)
+void dprc_remove_devices(struct fsl_mc_device *mc_bus_dev,
+			 struct fsl_mc_obj_desc *obj_desc_array,
+			 int num_child_objects_in_mc)
 {
 	if (num_child_objects_in_mc != 0) {
 		/*
@@ -104,6 +105,7 @@ static void dprc_remove_devices(struct fsl_mc_device *mc_bus_dev,
 				      __fsl_mc_device_remove);
 	}
 }
+EXPORT_SYMBOL_GPL(dprc_remove_devices);
 
 static int __fsl_mc_device_match(struct device *dev, void *data)
 {
@@ -220,8 +222,8 @@ static void dprc_add_new_devices(struct fsl_mc_device *mc_bus_dev,
  * 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: If argument is provided the function populates the
- * total number of IRQs created by objects in the DPRC.
+ * @alloc_interrupts: if true the function allocates the interrupt pool,
+ * otherwise the interrupt allocation is delayed
  *
  * Detects objects added and removed from a DPRC and synchronizes the
  * state of the Linux bus driver, MC by adding and removing
@@ -236,7 +238,7 @@ static void dprc_add_new_devices(struct fsl_mc_device *mc_bus_dev,
  * of the device drivers for the non-allocatable devices.
  */
 static int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev,
-			     unsigned int *total_irq_count)
+			    bool alloc_interrupts)
 {
 	int num_child_objects;
 	int dprc_get_obj_failures;
@@ -317,22 +319,21 @@ static int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev,
 	 * Allocate IRQ's before binding the scanned devices with their
 	 * respective drivers.
 	 */
-	if (dev_get_msi_domain(&mc_bus_dev->dev) && !mc_bus->irq_resources) {
+	if (dev_get_msi_domain(&mc_bus_dev->dev)) {
 		if (irq_count > FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS) {
 			dev_warn(&mc_bus_dev->dev,
 				 "IRQs needed (%u) exceed IRQs preallocated (%u)\n",
 				 irq_count, FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
 		}
 
-		error = fsl_mc_populate_irq_pool(mc_bus,
-				FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
-		if (error < 0)
-			return error;
+		if (alloc_interrupts && !mc_bus->irq_resources) {
+			error = fsl_mc_populate_irq_pool(mc_bus_dev,
+					 FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
+			if (error < 0)
+				return error;
+		}
 	}
 
-	if (total_irq_count)
-		*total_irq_count = irq_count;
-
 	dprc_remove_devices(mc_bus_dev, child_obj_desc_array,
 			    num_child_objects);
 
@@ -354,9 +355,10 @@ static int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev,
  * bus driver with the actual state of the MC by adding and removing
  * devices as appropriate.
  */
-static int dprc_scan_container(struct fsl_mc_device *mc_bus_dev)
+int dprc_scan_container(struct fsl_mc_device *mc_bus_dev,
+			bool alloc_interrupts)
 {
-	int error;
+	int error = 0;
 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
 
 	fsl_mc_init_all_resource_pools(mc_bus_dev);
@@ -365,16 +367,12 @@ static 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, NULL);
+	error = dprc_scan_objects(mc_bus_dev, alloc_interrupts);
 	mutex_unlock(&mc_bus->scan_mutex);
-	if (error < 0) {
-		fsl_mc_cleanup_all_resource_pools(mc_bus_dev);
-		return error;
-	}
 
-	return 0;
+	return error;
 }
-
+EXPORT_SYMBOL_GPL(dprc_scan_container);
 /**
  * dprc_irq0_handler - Regular ISR for DPRC interrupt 0
  *
@@ -434,9 +432,8 @@ static irqreturn_t dprc_irq0_handler_thread(int irq_num, void *arg)
 		      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);
+		error = dprc_scan_objects(mc_dev, true);
 		if (error < 0) {
 			/*
 			 * If the error is -ENXIO, we ignore it, as it indicates
@@ -451,12 +448,6 @@ static irqreturn_t dprc_irq0_handler_thread(int irq_num, void *arg)
 
 			goto out;
 		}
-
-		if (irq_count > FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS) {
-			dev_warn(dev,
-				 "IRQs needed (%u) exceed IRQs preallocated (%u)\n",
-				 irq_count, FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
-		}
 	}
 
 out:
@@ -597,25 +588,24 @@ error_free_irqs:
 }
 
 /**
- * dprc_probe - callback invoked when a DPRC is being bound to this driver
+ * dprc_setup - opens and creates a mc_io for DPRC
  *
  * @mc_dev: Pointer to fsl-mc device representing a DPRC
  *
  * It opens the physical DPRC in the MC.
- * It scans the DPRC to discover the MC objects contained in it.
- * It creates the interrupt pool for the MC bus associated with the DPRC.
- * It configures the interrupts for the DPRC device itself.
+ * It configures the DPRC portal used to communicate with MC
  */
-static int dprc_probe(struct fsl_mc_device *mc_dev)
+
+int dprc_setup(struct fsl_mc_device *mc_dev)
 {
-	int error;
-	size_t region_size;
 	struct device *parent_dev = mc_dev->dev.parent;
 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
+	struct irq_domain *mc_msi_domain;
 	bool mc_io_created = false;
 	bool msi_domain_set = false;
 	u16 major_ver, minor_ver;
-	struct irq_domain *mc_msi_domain;
+	size_t region_size;
+	int error;
 
 	if (!is_fsl_mc_bus_dprc(mc_dev))
 		return -EINVAL;
@@ -690,37 +680,63 @@ static int dprc_probe(struct fsl_mc_device *mc_dev)
 		goto error_cleanup_open;
 	}
 
-	mutex_init(&mc_bus->scan_mutex);
+	return 0;
+
+error_cleanup_open:
+	(void)dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
+
+error_cleanup_msi_domain:
+	if (msi_domain_set)
+		dev_set_msi_domain(&mc_dev->dev, NULL);
+
+	if (mc_io_created) {
+		fsl_destroy_mc_io(mc_dev->mc_io);
+		mc_dev->mc_io = NULL;
+	}
+
+	return error;
+}
+EXPORT_SYMBOL_GPL(dprc_setup);
+
+/**
+ * dprc_probe - callback invoked when a DPRC is being bound to this driver
+ *
+ * @mc_dev: Pointer to fsl-mc device representing a DPRC
+ *
+ * It opens the physical DPRC in the MC.
+ * It scans the DPRC to discover the MC objects contained in it.
+ * It creates the interrupt pool for the MC bus associated with the DPRC.
+ * It configures the interrupts for the DPRC device itself.
+ */
+static int dprc_probe(struct fsl_mc_device *mc_dev)
+{
+	int error;
+
+	error = dprc_setup(mc_dev);
+	if (error < 0)
+		return error;
 
 	/*
 	 * Discover MC objects in DPRC object:
 	 */
-	error = dprc_scan_container(mc_dev);
+	error = dprc_scan_container(mc_dev, true);
 	if (error < 0)
-		goto error_cleanup_open;
+		goto dprc_cleanup;
 
 	/*
 	 * Configure interrupt for the DPRC object associated with this MC bus:
 	 */
 	error = dprc_setup_irq(mc_dev);
 	if (error < 0)
-		goto error_cleanup_open;
+		goto scan_cleanup;
 
 	dev_info(&mc_dev->dev, "DPRC device bound to driver");
 	return 0;
 
-error_cleanup_open:
-	(void)dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
-
-error_cleanup_msi_domain:
-	if (msi_domain_set)
-		dev_set_msi_domain(&mc_dev->dev, NULL);
-
-	if (mc_io_created) {
-		fsl_destroy_mc_io(mc_dev->mc_io);
-		mc_dev->mc_io = NULL;
-	}
-
+scan_cleanup:
+	device_for_each_child(&mc_dev->dev, NULL, __fsl_mc_device_remove);
+dprc_cleanup:
+	dprc_cleanup(mc_dev);
 	return error;
 }
 
@@ -739,40 +755,39 @@ static void dprc_teardown_irq(struct fsl_mc_device *mc_dev)
 }
 
 /**
- * dprc_remove - callback invoked when a DPRC is being unbound from this driver
+ * dprc_cleanup - function that cleanups a DPRC
  *
  * @mc_dev: Pointer to fsl-mc device representing the DPRC
  *
- * It removes the DPRC's child objects from Linux (not from the MC) and
- * closes the DPRC device in the MC.
- * It tears down the interrupts that were configured for the DPRC device.
+ * It closes the DPRC device in the MC.
  * It destroys the interrupt pool associated with this MC bus.
  */
-static int dprc_remove(struct fsl_mc_device *mc_dev)
+
+int dprc_cleanup(struct fsl_mc_device *mc_dev)
 {
 	int error;
-	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
 
+	/* this function should be called only for DPRCs, it
+	 * is an error to call it for regular objects
+	 */
 	if (!is_fsl_mc_bus_dprc(mc_dev))
 		return -EINVAL;
-	if (!mc_dev->mc_io)
-		return -EINVAL;
-
-	if (!mc_bus->irq_resources)
-		return -EINVAL;
-
-	if (dev_get_msi_domain(&mc_dev->dev))
-		dprc_teardown_irq(mc_dev);
-
-	device_for_each_child(&mc_dev->dev, NULL, __fsl_mc_device_remove);
 
 	if (dev_get_msi_domain(&mc_dev->dev)) {
-		fsl_mc_cleanup_irq_pool(mc_bus);
+		fsl_mc_cleanup_irq_pool(mc_dev);
 		dev_set_msi_domain(&mc_dev->dev, NULL);
 	}
 
 	fsl_mc_cleanup_all_resource_pools(mc_dev);
 
+	/* if this step fails we cannot go further with cleanup as there is no way of
+	 * communicating with the firmware
+	 */
+	if (!mc_dev->mc_io) {
+		dev_err(&mc_dev->dev, "mc_io is NULL, tear down cannot be performed in firmware\n");
+		return -EINVAL;
+	}
+
 	error = dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
 	if (error < 0)
 		dev_err(&mc_dev->dev, "dprc_close() failed: %d\n", error);
@@ -782,6 +797,37 @@ static int dprc_remove(struct fsl_mc_device *mc_dev)
 		mc_dev->mc_io = NULL;
 	}
 
+	return 0;
+}
+EXPORT_SYMBOL_GPL(dprc_cleanup);
+
+/**
+ * dprc_remove - callback invoked when a DPRC is being unbound from this driver
+ *
+ * @mc_dev: Pointer to fsl-mc device representing the DPRC
+ *
+ * It removes the DPRC's child objects from Linux (not from the MC) and
+ * closes the DPRC device in the MC.
+ * It tears down the interrupts that were configured for the DPRC device.
+ * It destroys the interrupt pool associated with this MC bus.
+ */
+static int dprc_remove(struct fsl_mc_device *mc_dev)
+{
+	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
+
+	if (!is_fsl_mc_bus_dprc(mc_dev))
+		return -EINVAL;
+
+	if (!mc_bus->irq_resources)
+		return -EINVAL;
+
+	if (dev_get_msi_domain(&mc_dev->dev))
+		dprc_teardown_irq(mc_dev);
+
+	device_for_each_child(&mc_dev->dev, NULL, __fsl_mc_device_remove);
+
+	dprc_cleanup(mc_dev);
+
 	dev_info(&mc_dev->dev, "DPRC device unbound from driver");
 	return 0;
 }