firmware: ti_sci: Add helper apis to manage resources

Each resource with in the device can be uniquely identified as defined
by TISCI. Since this is generic across the devices, resource allocation
also can be made generic instead of each client driver handling the
resource. So add helper apis to manage the resource.

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Acked-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

1 files changed, 130 insertions, 0 deletions

diff --git a/drivers/firmware/ti_sci.c b/drivers/firmware/ti_sci.c
index 551895535767..ef93406ace1b 100644
--- a/drivers/firmware/ti_sci.c
+++ b/drivers/firmware/ti_sci.c
@@ -2262,6 +2262,136 @@ const struct ti_sci_handle *devm_ti_sci_get_by_phandle(struct device *dev,
 }
 EXPORT_SYMBOL_GPL(devm_ti_sci_get_by_phandle);
 
+/**
+ * ti_sci_get_free_resource() - Get a free resource from TISCI resource.
+ * @res:	Pointer to the TISCI resource
+ *
+ * Return: resource num if all went ok else TI_SCI_RESOURCE_NULL.
+ */
+u16 ti_sci_get_free_resource(struct ti_sci_resource *res)
+{
+	unsigned long flags;
+	u16 set, free_bit;
+
+	raw_spin_lock_irqsave(&res->lock, flags);
+	for (set = 0; set < res->sets; set++) {
+		free_bit = find_first_zero_bit(res->desc[set].res_map,
+					       res->desc[set].num);
+		if (free_bit != res->desc[set].num) {
+			set_bit(free_bit, res->desc[set].res_map);
+			raw_spin_unlock_irqrestore(&res->lock, flags);
+			return res->desc[set].start + free_bit;
+		}
+	}
+	raw_spin_unlock_irqrestore(&res->lock, flags);
+
+	return TI_SCI_RESOURCE_NULL;
+}
+EXPORT_SYMBOL_GPL(ti_sci_get_free_resource);
+
+/**
+ * ti_sci_release_resource() - Release a resource from TISCI resource.
+ * @res:	Pointer to the TISCI resource
+ * @id:		Resource id to be released.
+ */
+void ti_sci_release_resource(struct ti_sci_resource *res, u16 id)
+{
+	unsigned long flags;
+	u16 set;
+
+	raw_spin_lock_irqsave(&res->lock, flags);
+	for (set = 0; set < res->sets; set++) {
+		if (res->desc[set].start <= id &&
+		    (res->desc[set].num + res->desc[set].start) > id)
+			clear_bit(id - res->desc[set].start,
+				  res->desc[set].res_map);
+	}
+	raw_spin_unlock_irqrestore(&res->lock, flags);
+}
+EXPORT_SYMBOL_GPL(ti_sci_release_resource);
+
+/**
+ * ti_sci_get_num_resources() - Get the number of resources in TISCI resource
+ * @res:	Pointer to the TISCI resource
+ *
+ * Return: Total number of available resources.
+ */
+u32 ti_sci_get_num_resources(struct ti_sci_resource *res)
+{
+	u32 set, count = 0;
+
+	for (set = 0; set < res->sets; set++)
+		count += res->desc[set].num;
+
+	return count;
+}
+EXPORT_SYMBOL_GPL(ti_sci_get_num_resources);
+
+/**
+ * devm_ti_sci_get_of_resource() - Get a TISCI resource assigned to a device
+ * @handle:	TISCI handle
+ * @dev:	Device pointer to which the resource is assigned
+ * @dev_id:	TISCI device id to which the resource is assigned
+ * @of_prop:	property name by which the resource are represented
+ *
+ * Return: Pointer to ti_sci_resource if all went well else appropriate
+ *	   error pointer.
+ */
+struct ti_sci_resource *
+devm_ti_sci_get_of_resource(const struct ti_sci_handle *handle,
+			    struct device *dev, u32 dev_id, char *of_prop)
+{
+	struct ti_sci_resource *res;
+	u32 resource_subtype;
+	int i, ret;
+
+	res = devm_kzalloc(dev, sizeof(*res), GFP_KERNEL);
+	if (!res)
+		return ERR_PTR(-ENOMEM);
+
+	res->sets = of_property_count_elems_of_size(dev_of_node(dev), of_prop,
+						    sizeof(u32));
+	if (res->sets < 0) {
+		dev_err(dev, "%s resource type ids not available\n", of_prop);
+		return ERR_PTR(res->sets);
+	}
+
+	res->desc = devm_kcalloc(dev, res->sets, sizeof(*res->desc),
+				 GFP_KERNEL);
+	if (!res->desc)
+		return ERR_PTR(-ENOMEM);
+
+	for (i = 0; i < res->sets; i++) {
+		ret = of_property_read_u32_index(dev_of_node(dev), of_prop, i,
+						 &resource_subtype);
+		if (ret)
+			return ERR_PTR(-EINVAL);
+
+		ret = handle->ops.rm_core_ops.get_range(handle, dev_id,
+							resource_subtype,
+							&res->desc[i].start,
+							&res->desc[i].num);
+		if (ret) {
+			dev_err(dev, "dev = %d subtype %d not allocated for this host\n",
+				dev_id, resource_subtype);
+			return ERR_PTR(ret);
+		}
+
+		dev_dbg(dev, "dev = %d, subtype = %d, start = %d, num = %d\n",
+			dev_id, resource_subtype, res->desc[i].start,
+			res->desc[i].num);
+
+		res->desc[i].res_map =
+			devm_kzalloc(dev, BITS_TO_LONGS(res->desc[i].num) *
+				     sizeof(*res->desc[i].res_map), GFP_KERNEL);
+		if (!res->desc[i].res_map)
+			return ERR_PTR(-ENOMEM);
+	}
+	raw_spin_lock_init(&res->lock);
+
+	return res;
+}
+
 static int tisci_reboot_handler(struct notifier_block *nb, unsigned long mode,
 				void *cmd)
 {