[PATCH v2 08/13] irqchip: GICv3: ITS: device allocation and configuration

From: Marc Zyngier
Date: Tue Nov 18 2014 - 13:53:40 EST


The ITS has a notion of "device" that can write to it in order to
generate an interrupt.

Conversly, the driver maintains a per-ITS list of devices, together
with their configuration information, and uses this to configure
the HW.

Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
---
drivers/irqchip/irq-gic-v3-its.c | 74 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 74 insertions(+)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 03f9831..d687fd4 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -981,3 +981,77 @@ static void its_cpu_init_collection(void)

spin_unlock(&its_lock);
}
+
+static struct its_device *its_find_device(struct its_node *its, u32 dev_id)
+{
+ struct its_device *its_dev = NULL, *tmp;
+
+ raw_spin_lock(&its->lock);
+
+ list_for_each_entry(tmp, &its->its_device_list, entry) {
+ if (tmp->device_id == dev_id) {
+ its_dev = tmp;
+ break;
+ }
+ }
+
+ raw_spin_unlock(&its->lock);
+
+ return its_dev;
+}
+
+static struct its_device *its_create_device(struct its_node *its, u32 dev_id,
+ int nvecs)
+{
+ struct its_device *dev;
+ unsigned long *lpi_map;
+ void *itt;
+ int lpi_base;
+ int nr_lpis;
+ int cpu;
+ int sz;
+
+ dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+ sz = nvecs * its->ite_size;
+ sz = max(sz, ITS_ITT_ALIGN) + ITS_ITT_ALIGN - 1;
+ itt = kmalloc(sz, GFP_KERNEL);
+ lpi_map = its_lpi_alloc_chunks(nvecs, &lpi_base, &nr_lpis);
+
+ if (!dev || !itt || !lpi_map) {
+ kfree(dev);
+ kfree(itt);
+ kfree(lpi_map);
+ return NULL;
+ }
+
+ dev->its = its;
+ dev->itt = itt;
+ dev->nr_ites = nvecs;
+ dev->lpi_map = lpi_map;
+ dev->lpi_base = lpi_base;
+ dev->nr_lpis = nr_lpis;
+ dev->device_id = dev_id;
+ INIT_LIST_HEAD(&dev->entry);
+
+ raw_spin_lock(&its->lock);
+ list_add(&dev->entry, &its->its_device_list);
+ raw_spin_unlock(&its->lock);
+
+ /* Bind the device to the first possible CPU */
+ cpu = cpumask_first(cpu_online_mask);
+ dev->collection = &its->collections[cpu];
+
+ /* Map device to its ITT */
+ its_send_mapd(dev, 1);
+
+ return dev;
+}
+
+static void its_free_device(struct its_device *its_dev)
+{
+ raw_spin_lock(&its_dev->its->lock);
+ list_del(&its_dev->entry);
+ raw_spin_unlock(&its_dev->its->lock);
+ kfree(its_dev->itt);
+ kfree(its_dev);
+}
--
2.1.3

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