1 files changed, 200 insertions, 54 deletions

diff --git a/drivers/base/platform-msi.c b/drivers/base/platform-msi.c
index 5df4575b5ba7..a203896f204f 100644
--- a/drivers/base/platform-msi.c
+++ b/drivers/base/platform-msi.c
@@ -25,12 +25,16 @@
 #include <linux/slab.h>
 
 #define DEV_ID_SHIFT	24
+#define MAX_DEV_MSIS	(1 << (32 - DEV_ID_SHIFT))
 
 /*
  * Internal data structure containing a (made up, but unique) devid
  * and the callback to write the MSI message.
  */
 struct platform_msi_priv_data {
+	struct device		*dev;
+	void 			*host_data;
+	msi_alloc_info_t	arg;
 	irq_write_msi_msg_t	write_msg;
 	int			devid;
 };
@@ -110,39 +114,49 @@ static void platform_msi_update_chip_ops(struct msi_domain_info *info)
 		chip->irq_write_msi_msg = platform_msi_write_msg;
 }
 
-static void platform_msi_free_descs(struct device *dev)
+static void platform_msi_free_descs(struct device *dev, int base, int nvec)
 {
 	struct msi_desc *desc, *tmp;
 
 	list_for_each_entry_safe(desc, tmp, dev_to_msi_list(dev), list) {
-		list_del(&desc->list);
-		free_msi_entry(desc);
+		if (desc->platform.msi_index >= base &&
+		    desc->platform.msi_index < (base + nvec)) {
+			list_del(&desc->list);
+			free_msi_entry(desc);
+		}
 	}
 }
 
-static int platform_msi_alloc_descs(struct device *dev, int nvec,
-				    struct platform_msi_priv_data *data)
+static int platform_msi_alloc_descs_with_irq(struct device *dev, int virq,
+					     int nvec,
+					     struct platform_msi_priv_data *data)
 
 {
-	int i;
+	struct msi_desc *desc;
+	int i, base = 0;
 
-	for (i = 0; i < nvec; i++) {
-		struct msi_desc *desc;
+	if (!list_empty(dev_to_msi_list(dev))) {
+		desc = list_last_entry(dev_to_msi_list(dev),
+				       struct msi_desc, list);
+		base = desc->platform.msi_index + 1;
+	}
 
+	for (i = 0; i < nvec; i++) {
 		desc = alloc_msi_entry(dev);
 		if (!desc)
 			break;
 
 		desc->platform.msi_priv_data = data;
-		desc->platform.msi_index = i;
+		desc->platform.msi_index = base + i;
 		desc->nvec_used = 1;
+		desc->irq = virq ? virq + i : 0;
 
 		list_add_tail(&desc->list, dev_to_msi_list(dev));
 	}
 
 	if (i != nvec) {
 		/* Clean up the mess */
-		platform_msi_free_descs(dev);
+		platform_msi_free_descs(dev, base, nvec);
 
 		return -ENOMEM;
 	}
@@ -150,6 +164,13 @@ static int platform_msi_alloc_descs(struct device *dev, int nvec,
 	return 0;
 }
 
+static int platform_msi_alloc_descs(struct device *dev, int nvec,
+				    struct platform_msi_priv_data *data)
+
+{
+	return platform_msi_alloc_descs_with_irq(dev, 0, nvec, data);
+}
+
 /**
  * platform_msi_create_irq_domain - Create a platform MSI interrupt domain
  * @fwnode:		Optional fwnode of the interrupt controller
@@ -180,56 +201,75 @@ struct irq_domain *platform_msi_create_irq_domain(struct fwnode_handle *fwnode,
 	return domain;
 }
 
-/**
- * platform_msi_domain_alloc_irqs - Allocate MSI interrupts for @dev
- * @dev:		The device for which to allocate interrupts
- * @nvec:		The number of interrupts to allocate
- * @write_msi_msg:	Callback to write an interrupt message for @dev
- *
- * Returns:
- * Zero for success, or an error code in case of failure
- */
-int platform_msi_domain_alloc_irqs(struct device *dev, unsigned int nvec,
-				   irq_write_msi_msg_t write_msi_msg)
+static struct platform_msi_priv_data *
+platform_msi_alloc_priv_data(struct device *dev, unsigned int nvec,
+			     irq_write_msi_msg_t write_msi_msg)
 {
-	struct platform_msi_priv_data *priv_data;
-	int err;
-
+	struct platform_msi_priv_data *datap;
 	/*
 	 * Limit the number of interrupts to 256 per device. Should we
 	 * need to bump this up, DEV_ID_SHIFT should be adjusted
 	 * accordingly (which would impact the max number of MSI
 	 * capable devices).
 	 */
-	if (!dev->msi_domain || !write_msi_msg || !nvec ||
-	    nvec > (1 << (32 - DEV_ID_SHIFT)))
-		return -EINVAL;
+	if (!dev->msi_domain || !write_msi_msg || !nvec || nvec > MAX_DEV_MSIS)
+		return ERR_PTR(-EINVAL);
 
 	if (dev->msi_domain->bus_token != DOMAIN_BUS_PLATFORM_MSI) {
 		dev_err(dev, "Incompatible msi_domain, giving up\n");
-		return -EINVAL;
+		return ERR_PTR(-EINVAL);
 	}
 
 	/* Already had a helping of MSI? Greed... */
 	if (!list_empty(dev_to_msi_list(dev)))
-		return -EBUSY;
+		return ERR_PTR(-EBUSY);
+
+	datap = kzalloc(sizeof(*datap), GFP_KERNEL);
+	if (!datap)
+		return ERR_PTR(-ENOMEM);
+
+	datap->devid = ida_simple_get(&platform_msi_devid_ida,
+				      0, 1 << DEV_ID_SHIFT, GFP_KERNEL);
+	if (datap->devid < 0) {
+		int err = datap->devid;
+		kfree(datap);
+		return ERR_PTR(err);
+	}
 
-	priv_data = kzalloc(sizeof(*priv_data), GFP_KERNEL);
-	if (!priv_data)
-		return -ENOMEM;
+	datap->write_msg = write_msi_msg;
+	datap->dev = dev;
 
-	priv_data->devid = ida_simple_get(&platform_msi_devid_ida,
-					  0, 1 << DEV_ID_SHIFT, GFP_KERNEL);
-	if (priv_data->devid < 0) {
-		err = priv_data->devid;
-		goto out_free_data;
-	}
+	return datap;
+}
+
+static void platform_msi_free_priv_data(struct platform_msi_priv_data *data)
+{
+	ida_simple_remove(&platform_msi_devid_ida, data->devid);
+	kfree(data);
+}
+
+/**
+ * platform_msi_domain_alloc_irqs - Allocate MSI interrupts for @dev
+ * @dev:		The device for which to allocate interrupts
+ * @nvec:		The number of interrupts to allocate
+ * @write_msi_msg:	Callback to write an interrupt message for @dev
+ *
+ * Returns:
+ * Zero for success, or an error code in case of failure
+ */
+int platform_msi_domain_alloc_irqs(struct device *dev, unsigned int nvec,
+				   irq_write_msi_msg_t write_msi_msg)
+{
+	struct platform_msi_priv_data *priv_data;
+	int err;
 
-	priv_data->write_msg = write_msi_msg;
+	priv_data = platform_msi_alloc_priv_data(dev, nvec, write_msi_msg);
+	if (IS_ERR(priv_data))
+		return PTR_ERR(priv_data);
 
 	err = platform_msi_alloc_descs(dev, nvec, priv_data);
 	if (err)
-		goto out_free_id;
+		goto out_free_priv_data;
 
 	err = msi_domain_alloc_irqs(dev->msi_domain, dev, nvec);
 	if (err)
@@ -238,11 +278,9 @@ int platform_msi_domain_alloc_irqs(struct device *dev, unsigned int nvec,
 	return 0;
 
 out_free_desc:
-	platform_msi_free_descs(dev);
-out_free_id:
-	ida_simple_remove(&platform_msi_devid_ida, priv_data->devid);
-out_free_data:
-	kfree(priv_data);
+	platform_msi_free_descs(dev, 0, nvec);
+out_free_priv_data:
+	platform_msi_free_priv_data(priv_data);
 
 	return err;
 }
@@ -253,18 +291,126 @@ out_free_data:
  */
 void platform_msi_domain_free_irqs(struct device *dev)
 {
-	struct msi_desc *desc;
+	if (!list_empty(dev_to_msi_list(dev))) {
+		struct msi_desc *desc;
+
+		desc = first_msi_entry(dev);
+		platform_msi_free_priv_data(desc->platform.msi_priv_data);
+	}
+
+	msi_domain_free_irqs(dev->msi_domain, dev);
+	platform_msi_free_descs(dev, 0, MAX_DEV_MSIS);
+}
+
+/**
+ * platform_msi_get_host_data - Query the private data associated with
+ *                              a platform-msi domain
+ * @domain:	The platform-msi domain
+ *
+ * Returns the private data provided when calling
+ * platform_msi_create_device_domain.
+ */
+void *platform_msi_get_host_data(struct irq_domain *domain)
+{
+	struct platform_msi_priv_data *data = domain->host_data;
+	return data->host_data;
+}
+
+/**
+ * platform_msi_create_device_domain - Create a platform-msi domain
+ *
+ * @dev:		The device generating the MSIs
+ * @nvec:		The number of MSIs that need to be allocated
+ * @write_msi_msg:	Callback to write an interrupt message for @dev
+ * @ops:		The hierarchy domain operations to use
+ * @host_data:		Private data associated to this domain
+ *
+ * Returns an irqdomain for @nvec interrupts
+ */
+struct irq_domain *
+platform_msi_create_device_domain(struct device *dev,
+				  unsigned int nvec,
+				  irq_write_msi_msg_t write_msi_msg,
+				  const struct irq_domain_ops *ops,
+				  void *host_data)
+{
+	struct platform_msi_priv_data *data;
+	struct irq_domain *domain;
+	int err;
+
+	data = platform_msi_alloc_priv_data(dev, nvec, write_msi_msg);
+	if (IS_ERR(data))
+		return NULL;
+
+	data->host_data = host_data;
+	domain = irq_domain_create_hierarchy(dev->msi_domain, 0, nvec,
+					     of_node_to_fwnode(dev->of_node),
+					     ops, data);
+	if (!domain)
+		goto free_priv;
 
-	desc = first_msi_entry(dev);
-	if (desc) {
-		struct platform_msi_priv_data *data;
+	err = msi_domain_prepare_irqs(domain->parent, dev, nvec, &data->arg);
+	if (err)
+		goto free_domain;
+
+	return domain;
 
-		data = desc->platform.msi_priv_data;
+free_domain:
+	irq_domain_remove(domain);
+free_priv:
+	platform_msi_free_priv_data(data);
+	return NULL;
+}
+
+/**
+ * platform_msi_domain_free - Free interrupts associated with a platform-msi
+ *                            domain
+ *
+ * @domain:	The platform-msi domain
+ * @virq:	The base irq from which to perform the free operation
+ * @nvec:	How many interrupts to free from @virq
+ */
+void platform_msi_domain_free(struct irq_domain *domain, unsigned int virq,
+			      unsigned int nvec)
+{
+	struct platform_msi_priv_data *data = domain->host_data;
+	struct msi_desc *desc;
+	for_each_msi_entry(desc, data->dev) {
+		if (WARN_ON(!desc->irq || desc->nvec_used != 1))
+			return;
+		if (!(desc->irq >= virq && desc->irq < (virq + nvec)))
+			continue;
 
-		ida_simple_remove(&platform_msi_devid_ida, data->devid);
-		kfree(data);
+		irq_domain_free_irqs_common(domain, desc->irq, 1);
 	}
+}
 
-	msi_domain_free_irqs(dev->msi_domain, dev);
-	platform_msi_free_descs(dev);
+/**
+ * platform_msi_domain_alloc - Allocate interrupts associated with
+ *			       a platform-msi domain
+ *
+ * @domain:	The platform-msi domain
+ * @virq:	The base irq from which to perform the allocate operation
+ * @nvec:	How many interrupts to free from @virq
+ *
+ * Return 0 on success, or an error code on failure. Must be called
+ * with irq_domain_mutex held (which can only be done as part of a
+ * top-level interrupt allocation).
+ */
+int platform_msi_domain_alloc(struct irq_domain *domain, unsigned int virq,
+			      unsigned int nr_irqs)
+{
+	struct platform_msi_priv_data *data = domain->host_data;
+	int err;
+
+	err = platform_msi_alloc_descs_with_irq(data->dev, virq, nr_irqs, data);
+	if (err)
+		return err;
+
+	err = msi_domain_populate_irqs(domain->parent, data->dev,
+				       virq, nr_irqs, &data->arg);
+	if (err)
+		platform_msi_domain_free(domain, virq, nr_irqs);
+
+	return err;
 }