bus/fsl-mc: Export IRQ pool handling functions to be used by VFIO

The IRQ pool handling functions can be used by both DPRC
driver and VFIO. Adapt and export those functions.
Reviewed-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Acked-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Signed-off-by: Diana Craciun <diana.craciun@oss.nxp.com>
Link: https://lore.kernel.org/r/20200929085441.17448-12-diana.craciun@oss.nxp.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/bus/fsl-mc/dprc-driver.c

@@ -327,8 +327,8 @@ static int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev,
 		}
 
 		if (alloc_interrupts && !mc_bus->irq_resources) {
-			error = fsl_mc_populate_irq_pool(mc_bus,
-				FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
+			error = fsl_mc_populate_irq_pool(mc_bus_dev,
+					 FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
 			if (error < 0)
 				return error;
 		}
@@ -766,8 +766,6 @@ static void dprc_teardown_irq(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
@@ -776,7 +774,7 @@ int dprc_cleanup(struct fsl_mc_device *mc_dev)
 		return -EINVAL;
 
 	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);
 	}
 

drivers/bus/fsl-mc/fsl-mc-allocator.c

@@ -344,7 +344,7 @@ EXPORT_SYMBOL_GPL(fsl_mc_object_free);
  * Initialize the interrupt pool associated with an fsl-mc bus.
  * It allocates a block of IRQs from the GIC-ITS.
  */
-int fsl_mc_populate_irq_pool(struct fsl_mc_bus *mc_bus,
+int fsl_mc_populate_irq_pool(struct fsl_mc_device *mc_bus_dev,
 			     unsigned int irq_count)
 {
 	unsigned int i;
@@ -352,10 +352,14 @@ int fsl_mc_populate_irq_pool(struct fsl_mc_bus *mc_bus,
 	struct fsl_mc_device_irq *irq_resources;
 	struct fsl_mc_device_irq *mc_dev_irq;
 	int error;
-	struct fsl_mc_device *mc_bus_dev = &mc_bus->mc_dev;
+	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
 	struct fsl_mc_resource_pool *res_pool =
 			&mc_bus->resource_pools[FSL_MC_POOL_IRQ];
 
+	/* do nothing if the IRQ pool is already populated */
+	if (mc_bus->irq_resources)
+		return 0;
+
 	if (irq_count == 0 ||
 	    irq_count > FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS)
 		return -EINVAL;
@@ -407,9 +411,9 @@ EXPORT_SYMBOL_GPL(fsl_mc_populate_irq_pool);
  * Teardown the interrupt pool associated with an fsl-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)
+void fsl_mc_cleanup_irq_pool(struct fsl_mc_device *mc_bus_dev)
 {
-	struct fsl_mc_device *mc_bus_dev = &mc_bus->mc_dev;
+	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
 	struct fsl_mc_resource_pool *res_pool =
 			&mc_bus->resource_pools[FSL_MC_POOL_IRQ];
 

drivers/bus/fsl-mc/fsl-mc-private.h

@@ -519,11 +519,6 @@ struct dpcon_cmd_set_notification {
 	__le64 user_ctx;
 };
 
-/**
- * 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
 
 /**
  * struct fsl_mc_resource_pool - Pool of MC resources of a given
@@ -598,11 +593,6 @@ void fsl_mc_msi_domain_free_irqs(struct device *dev);
 
 struct irq_domain *fsl_mc_find_msi_domain(struct device *dev);
 
-int 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);
-
 int __must_check fsl_create_mc_io(struct device *dev,
 				  phys_addr_t mc_portal_phys_addr,
 				  u32 mc_portal_size,

include/linux/fsl/mc.h

@@ -542,6 +542,17 @@ int dprc_cleanup(struct fsl_mc_device *mc_dev);
 
 int dprc_setup(struct fsl_mc_device *mc_dev);
 
+/**
+ * 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
+
+int fsl_mc_populate_irq_pool(struct fsl_mc_device *mc_bus_dev,
+			     unsigned int irq_count);
+
+void fsl_mc_cleanup_irq_pool(struct fsl_mc_device *mc_bus_dev);
+
 /*
  * Data Path Buffer Pool (DPBP) API
  * Contains initialization APIs and runtime control APIs for DPBP