vfio/fsl-mc: Return get_irq info for fsl-mc device

This patch add support for VFIO_DEVICE_GET_IRQ_INFO
for fsl-mc devices

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@nxp.com>

4 files changed, 152 insertions, 5 deletions

diff --git a/drivers/vfio/fsl-mc/Makefile b/drivers/vfio/fsl-mc/Makefile
index 6f2b806..2aca75a 100644
--- a/drivers/vfio/fsl-mc/Makefile
+++ b/drivers/vfio/fsl-mc/Makefile
@@ -1,2 +1,2 @@
 vfio-fsl_mc-y := vfio_fsl_mc.o
-obj-$(CONFIG_VFIO_FSL_MC) += vfio_fsl_mc.o
+obj-$(CONFIG_VFIO_FSL_MC) += vfio_fsl_mc.o vfio_fsl_mc_intr.o
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
index 29312b9..91decea 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c
@@ -87,12 +87,18 @@ static int vfio_fsl_mc_open(void *device_data)
 		ret = vfio_fsl_mc_regions_init(vdev);
 		if (ret)
 			goto error_region_init;
+
+		ret = vfio_fsl_mc_irqs_init(vdev);
+		if (ret)
+			goto error_irq_init;
 	}
 
 	vdev->refcnt++;
 	mutex_unlock(&driver_lock);
 	return 0;
 
+error_irq_init:
+	vfio_fsl_mc_regions_cleanup(vdev);
 error_region_init:
 	mutex_unlock(&driver_lock);
 	if (ret)
@@ -107,8 +113,10 @@ static void vfio_fsl_mc_release(void *device_data)
 
 	mutex_lock(&driver_lock);
 
-	if (!(--vdev->refcnt))
+	if (!(--vdev->refcnt)) {
 		vfio_fsl_mc_regions_cleanup(vdev);
+		vfio_fsl_mc_irqs_cleanup(vdev);
+	}
 
 	mutex_unlock(&driver_lock);
 
@@ -168,7 +176,31 @@ static long vfio_fsl_mc_ioctl(void *device_data, unsigned int cmd,
 	}
 	case VFIO_DEVICE_GET_IRQ_INFO:
 	{
-		return -EINVAL;
+		struct vfio_irq_info info;
+
+		minsz = offsetofend(struct vfio_irq_info, count);
+		if (copy_from_user(&info, (void __user *)arg, minsz))
+			return -EFAULT;
+
+		if (info.argsz < minsz)
+			return -EINVAL;
+
+		if (info.index >= mc_dev->obj_desc.irq_count)
+			return -EINVAL;
+
+		if (vdev->mc_irqs != NULL) {
+			info.flags = vdev->mc_irqs[info.index].flags;
+			info.count = vdev->mc_irqs[info.index].count;
+		} else {
+			/*
+			 * If IRQs are not initialized then these can not
+			 * be configuted and used by user-space/
+			 */
+			info.flags = 0;
+			info.count = 0;
+		}
+
+		return copy_to_user((void __user *)arg, &info, minsz);
 	}
 	case VFIO_DEVICE_SET_IRQS:
 	{
@@ -282,6 +314,7 @@ static int vfio_fsl_mc_initialize_dprc(struct vfio_fsl_mc_device *vdev)
 	struct fsl_mc_device *mc_dev = vdev->mc_dev;
 	struct device *dev = &mc_dev->dev;
 	struct fsl_mc_bus *mc_bus;
+	struct irq_domain *mc_msi_domain;
 	unsigned int irq_count;
 	int ret;
 
@@ -301,7 +334,7 @@ static int vfio_fsl_mc_initialize_dprc(struct vfio_fsl_mc_device *vdev)
 				     FSL_MC_IO_ATOMIC_CONTEXT_PORTAL,
 				     &mc_dev->mc_io);
 	if (ret < 0)
-		return ret;
+		goto clean_msi_domain;
 
 	/* Reset MCP before move on */
 	ret = fsl_mc_portal_reset(mc_dev->mc_io);
@@ -310,6 +343,13 @@ static int vfio_fsl_mc_initialize_dprc(struct vfio_fsl_mc_device *vdev)
 		goto free_mc_portal;
 	}
 
+	/* MSI domain set up */
+	ret = fsl_mc_find_msi_domain(root_dprc_dev->parent, &mc_msi_domain);
+	if (ret < 0)
+		goto free_mc_portal;
+
+	dev_set_msi_domain(&mc_dev->dev, mc_msi_domain);
+
 	ret = dprc_open(mc_dev->mc_io, 0, mc_dev->obj_desc.id,
 			&mc_dev->mc_handle);
 	if (ret) {
@@ -322,6 +362,15 @@ static int vfio_fsl_mc_initialize_dprc(struct vfio_fsl_mc_device *vdev)
 
 	mc_bus = to_fsl_mc_bus(mc_dev);
 
+	if (!mc_bus->irq_resources) {
+		irq_count = FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS;
+		ret = fsl_mc_populate_irq_pool(mc_bus, irq_count);
+		if (ret < 0) {
+			dev_err(dev, "%s: Failed to init irq-pool\n", __func__);
+			goto clean_resource_pool;
+		}
+	}
+
 	mutex_init(&mc_bus->scan_mutex);
 
 	mutex_lock(&mc_bus->scan_mutex);
@@ -330,17 +379,30 @@ static int vfio_fsl_mc_initialize_dprc(struct vfio_fsl_mc_device *vdev)
 	mutex_unlock(&mc_bus->scan_mutex);
 	if (ret) {
 		dev_err(dev, "dprc_scan_objects() fails (%d)\n", ret);
-		goto clean_resource_pool;
+		goto clean_irq_pool;
+	}
+
+	if (irq_count > FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS) {
+		dev_warn(&mc_dev->dev,
+			 "IRQs needed (%u) exceed IRQs preallocated (%u)\n",
+			 irq_count, FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
 	}
 
 	return 0;
 
+clean_irq_pool:
+	fsl_mc_cleanup_irq_pool(mc_bus);
+
 clean_resource_pool:
 	fsl_mc_cleanup_all_resource_pools(mc_dev);
 	dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
 
 free_mc_portal:
 	fsl_mc_portal_free(mc_dev->mc_io);
+
+clean_msi_domain:
+	dev_set_msi_domain(&mc_dev->dev, NULL);
+
 	return ret;
 }
 
@@ -361,6 +423,7 @@ static int vfio_fsl_mc_device_remove(struct device *dev, void *data)
 static void vfio_fsl_mc_cleanup_dprc(struct vfio_fsl_mc_device *vdev)
 {
 	struct fsl_mc_device *mc_dev = vdev->mc_dev;
+	struct fsl_mc_bus *mc_bus;
 
 	/* device must be DPRC */
 	if (strcmp(mc_dev->obj_desc.type, "dprc"))
@@ -368,6 +431,12 @@ static void vfio_fsl_mc_cleanup_dprc(struct vfio_fsl_mc_device *vdev)
 
 	device_for_each_child(&mc_dev->dev, NULL, vfio_fsl_mc_device_remove);
 
+	mc_bus = to_fsl_mc_bus(mc_dev);
+	if (dev_get_msi_domain(&mc_dev->dev))
+		fsl_mc_cleanup_irq_pool(mc_bus);
+
+	dev_set_msi_domain(&mc_dev->dev, NULL);
+
 	fsl_mc_cleanup_all_resource_pools(mc_dev);
 	dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
 	fsl_mc_portal_free(mc_dev->mc_io);
@@ -418,6 +487,10 @@ static int vfio_fsl_mc_probe(struct fsl_mc_device *mc_dev)
 		}
 
 		mc_dev->mc_io = mc_bus_dev->mc_io;
+
+		/* Inherit parent MSI domain */
+		dev_set_msi_domain(&mc_dev->dev,
+				   dev_get_msi_domain(mc_dev->dev.parent));
 	}
 	return 0;
 
@@ -438,6 +511,8 @@ static int vfio_fsl_mc_remove(struct fsl_mc_device *mc_dev)
 
 	if (strcmp(mc_dev->obj_desc.type, "dprc") == 0)
 		vfio_fsl_mc_cleanup_dprc(vdev);
+	else
+		dev_set_msi_domain(&mc_dev->dev, NULL);
 
 	mc_dev->mc_io = NULL;
 
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c b/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
new file mode 100644
index 0000000..d86dc04
--- /dev/null
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
@@ -0,0 +1,64 @@
+/*
+ * Freescale Management Complex (MC) device passthrough using VFIO
+ *
+ * Copyright (C) 2013-2016 Freescale Semiconductor, Inc.
+ * Author: Bharat Bhushan <bharat.bhushan@nxp.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/vfio.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#include "vfio_fsl_mc_private.h"
+#include "../../staging/fsl-mc/include/mc.h"
+
+int vfio_fsl_mc_irqs_init(struct vfio_fsl_mc_device *vdev)
+{
+	struct fsl_mc_device *mc_dev = vdev->mc_dev;
+	struct vfio_fsl_mc_irq *mc_irq;
+	int irq_count;
+	int ret, i;
+
+	/* Device does not support any interrupt */
+	if (mc_dev->obj_desc.irq_count == 0)
+		return 0;
+
+	irq_count = mc_dev->obj_desc.irq_count;
+
+	mc_irq = kcalloc(irq_count, sizeof(*mc_irq), GFP_KERNEL);
+	if (mc_irq == NULL)
+		return -ENOMEM;
+
+	/* Allocate IRQs */
+	ret = fsl_mc_allocate_irqs(mc_dev);
+	if  (ret) {
+		kfree(mc_irq);
+		return ret;
+	}
+
+	for (i = 0; i < irq_count; i++) {
+		mc_irq[i].count = 1;
+		mc_irq[i].flags = 0;
+	}
+
+	vdev->mc_irqs = mc_irq;
+
+	return 0;
+}
+
+/* Free All IRQs for the given MC object */
+void vfio_fsl_mc_irqs_cleanup(struct vfio_fsl_mc_device *vdev)
+{
+	struct fsl_mc_device *mc_dev = vdev->mc_dev;
+
+	/* Device does not support any interrupt */
+	if (mc_dev->obj_desc.irq_count == 0)
+		return;
+
+	fsl_mc_free_irqs(mc_dev);
+	kfree(vdev->mc_irqs);
+}
diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
index e9d7f3b..6d31c3c 100644
--- a/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
+++ b/drivers/vfio/fsl-mc/vfio_fsl_mc_private.h
@@ -21,6 +21,11 @@
 #define VFIO_FSL_MC_INDEX_TO_OFFSET(index)	\
 	((u64)(index) << VFIO_FSL_MC_OFFSET_SHIFT)
 
+struct vfio_fsl_mc_irq {
+	u32			flags;
+	u32			count;
+};
+
 struct vfio_fsl_mc_region {
 	u32			flags;
 #define VFIO_FSL_MC_REGION_TYPE_MMIO  1
@@ -35,6 +40,9 @@ struct vfio_fsl_mc_device {
 	int				refcnt;
 	u32				num_regions;
 	struct vfio_fsl_mc_region	*regions;
+	struct vfio_fsl_mc_irq		*mc_irqs;
 };
 
+int vfio_fsl_mc_irqs_init(struct vfio_fsl_mc_device *vdev);
+void vfio_fsl_mc_irqs_cleanup(struct vfio_fsl_mc_device *vdev);
 #endif /* VFIO_PCI_PRIVATE_H */