[PATCH 05/17] IB/hfi1: Add shared ASIC structure

Dennis Dalessandro
2016-03-05T16:49:45Z

Create a shared structure to exist between devices that share the
same ASIC.

Reviewed-by: Mitko Haralanov <mitko.haralanov-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Reviewed-by: Easwar Hariharan <easwar.hariharan-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Signed-off-by: Dean Luick <dean.luick-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Signed-off-by: Jubin John <jubin.john-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
---
drivers/infiniband/hw/hfi1/chip.c | 28 +++++++++++++++++++++++++---
drivers/infiniband/hw/hfi1/hfi.h | 9 +++++++++
drivers/infiniband/hw/hfi1/init.c | 20 ++++++++++++++++++++
3 files changed, 54 insertions(+), 3 deletions(-)

diff --git a/drivers/infiniband/hw/hfi1/chip.c b/drivers/infiniband/hw/hfi1/chip.c
index 0874287..686cadf 100644
--- a/drivers/infiniband/hw/hfi1/chip.c
+++ b/drivers/infiniband/hw/hfi1/chip.c
@@ -13800,15 +13800,20 @@ void hfi1_start_cleanup(struct hfi1_devdata *dd)
((dev)->base_guid & ~(1ULL << GUID_HFI_INDEX_SHIFT))

/*
+ * Information can be shared between the two HFIs on the same ASIC
+ * in the same OS. This function finds the peer device and sets
+ * up a shared structure.
+ *
* Certain chip functions need to be initialized only once per asic
* instead of per-device. This function finds the peer device and
* checks whether that chip initialization needs to be done by this
* device.
*/
-static void asic_should_init(struct hfi1_devdata *dd)
+static int init_asic_data(struct hfi1_devdata *dd)
{
unsigned long flags;
struct hfi1_devdata *tmp, *peer = NULL;
+ int ret = 0;

spin_lock_irqsave(&hfi1_devs_lock, flags);
/* Find our peer device */
@@ -13826,7 +13831,22 @@ static void asic_should_init(struct hfi1_devdata *dd)
*/
if (!peer || !(peer->flags & HFI1_DO_INIT_ASIC))
dd->flags |= HFI1_DO_INIT_ASIC;
+
+ if (peer) {
+ dd->asic_data = peer->asic_data;
+ } else {
+ dd->asic_data = kzalloc(sizeof(*dd->asic_data), GFP_KERNEL);
+ if (!dd->asic_data) {
+ ret = -ENOMEM;
+ goto done;
+ }
+ mutex_init(&dd->asic_data->asic_resource_mutex);
+ }
+ dd->asic_data->dds[dd->hfi1_id] = dd; /* self back-pointer */
+
+done:
spin_unlock_irqrestore(&hfi1_devs_lock, flags);
+ return ret;
}

/*
@@ -14076,8 +14096,10 @@ struct hfi1_devdata *hfi1_init_dd(struct pci_dev *pdev,
/* needs to be done before we look for the peer device */
read_guid(dd);

- /* should this device init the ASIC block? */
- asic_should_init(dd);
+ /* set up shared ASIC data with peer device */
+ ret = init_asic_data(dd);
+ if (ret)
+ goto bail_cleanup;

/* obtain chip sizes, reset chip CSRs */
init_chip(dd);
diff --git a/drivers/infiniband/hw/hfi1/hfi.h b/drivers/infiniband/hw/hfi1/hfi.h
index 9215482..e71a1c2 100644
--- a/drivers/infiniband/hw/hfi1/hfi.h
+++ b/drivers/infiniband/hw/hfi1/hfi.h
@@ -805,6 +805,12 @@ struct hfi1_temp {
u8 triggers; /* temperature triggers */
};

+/* common data between shared ASIC HFIs */
+struct hfi1_asic_data {
+ struct hfi1_devdata *dds[2]; /* back pointers */
+ struct mutex asic_resource_mutex;
+};
+
/* device data struct now contains only "general per-device" info.
* fields related to a physical IB port are in a hfi1_pportdata struct.
*/
@@ -880,6 +886,9 @@ struct hfi1_devdata {
wait_queue_head_t sdma_unfreeze_wq;
atomic_t sdma_unfreeze_count;

+ /* common data between shared ASIC HFIs in this OS */
+ struct hfi1_asic_data *asic_data;
+
/* hfi1_pportdata, points to array of (physical) port-specific
* data structs, indexed by pidx (0..n-1)
*/
diff --git a/drivers/infiniband/hw/hfi1/init.c b/drivers/infiniband/hw/hfi1/init.c
index 37b3ce8..260a8e1 100644
--- a/drivers/infiniband/hw/hfi1/init.c
+++ b/drivers/infiniband/hw/hfi1/init.c
@@ -974,6 +974,25 @@ void hfi1_free_ctxtdata(struct hfi1_devdata *dd, struct hfi1_ctxtdata *rcd)
kfree(rcd);
}

+/*
+ * Release our hold on the shared asic data. If we are the last one,
+ * free the structure. Must be holding hfi1_devs_lock.
+ */
+static void release_asic_data(struct hfi1_devdata *dd)
+{
+ int other;
+
+ if (!dd->asic_data)
+ return;
+ dd->asic_data->dds[dd->hfi1_id] = NULL;
+ other = dd->hfi1_id ? 0 : 1;
+ if (!dd->asic_data->dds[other]) {
+ /* we are the last holder, free it */
+ kfree(dd->asic_data);
+ }
+ dd->asic_data = NULL;
+}
+
void hfi1_free_devdata(struct hfi1_devdata *dd)
{
unsigned long flags;
@@ -981,6 +1000,7 @@ void hfi1_free_devdata(struct hfi1_devdata *dd)
spin_lock_irqsave(&hfi1_devs_lock, flags);
idr_remove(&hfi1_unit_table, dd->unit);
list_del(&dd->list);
+ release_asic_data(dd);
spin_unlock_irqrestore(&hfi1_devs_lock, flags);
free_platform_config(dd);
rcu_barrier(); /* wait for rcu callbacks to complete */