[PATCH 5.2 030/143] habanalabs: fix completion queue handling when host is BE

From: Greg Kroah-Hartman
Date: Wed Sep 04 2019 - 14:10:17 EST


[ Upstream commit 4e87334a0ef43663019dbaf3638ad10fd8c3320c ]

This patch fix the CQ irq handler to work in hosts with BE architecture.
It adds the correct endian-swapping macros around the relevant memory
accesses.

Signed-off-by: Ben Segal <bpsegal20@xxxxxxxxx>
Reviewed-by: Oded Gabbay <oded.gabbay@xxxxxxxxx>
Signed-off-by: Oded Gabbay <oded.gabbay@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/misc/habanalabs/irq.c | 27 +++++++++++++--------------
1 file changed, 13 insertions(+), 14 deletions(-)

diff --git a/drivers/misc/habanalabs/irq.c b/drivers/misc/habanalabs/irq.c
index ea9f72ff456cf..199791b57caf2 100644
--- a/drivers/misc/habanalabs/irq.c
+++ b/drivers/misc/habanalabs/irq.c
@@ -80,8 +80,7 @@ irqreturn_t hl_irq_handler_cq(int irq, void *arg)
struct hl_cs_job *job;
bool shadow_index_valid;
u16 shadow_index;
- u32 *cq_entry;
- u32 *cq_base;
+ struct hl_cq_entry *cq_entry, *cq_base;

if (hdev->disabled) {
dev_dbg(hdev->dev,
@@ -90,29 +89,29 @@ irqreturn_t hl_irq_handler_cq(int irq, void *arg)
return IRQ_HANDLED;
}

- cq_base = (u32 *) (uintptr_t) cq->kernel_address;
+ cq_base = (struct hl_cq_entry *) (uintptr_t) cq->kernel_address;

while (1) {
- bool entry_ready = ((cq_base[cq->ci] & CQ_ENTRY_READY_MASK)
+ bool entry_ready = ((le32_to_cpu(cq_base[cq->ci].data) &
+ CQ_ENTRY_READY_MASK)
>> CQ_ENTRY_READY_SHIFT);

if (!entry_ready)
break;

- cq_entry = (u32 *) &cq_base[cq->ci];
+ cq_entry = (struct hl_cq_entry *) &cq_base[cq->ci];

- /*
- * Make sure we read CQ entry contents after we've
+ /* Make sure we read CQ entry contents after we've
* checked the ownership bit.
*/
dma_rmb();

- shadow_index_valid =
- ((*cq_entry & CQ_ENTRY_SHADOW_INDEX_VALID_MASK)
+ shadow_index_valid = ((le32_to_cpu(cq_entry->data) &
+ CQ_ENTRY_SHADOW_INDEX_VALID_MASK)
>> CQ_ENTRY_SHADOW_INDEX_VALID_SHIFT);

- shadow_index = (u16)
- ((*cq_entry & CQ_ENTRY_SHADOW_INDEX_MASK)
+ shadow_index = (u16) ((le32_to_cpu(cq_entry->data) &
+ CQ_ENTRY_SHADOW_INDEX_MASK)
>> CQ_ENTRY_SHADOW_INDEX_SHIFT);

queue = &hdev->kernel_queues[cq->hw_queue_id];
@@ -122,8 +121,7 @@ irqreturn_t hl_irq_handler_cq(int irq, void *arg)
queue_work(hdev->cq_wq, &job->finish_work);
}

- /*
- * Update ci of the context's queue. There is no
+ /* Update ci of the context's queue. There is no
* need to protect it with spinlock because this update is
* done only inside IRQ and there is a different IRQ per
* queue
@@ -131,7 +129,8 @@ irqreturn_t hl_irq_handler_cq(int irq, void *arg)
queue->ci = hl_queue_inc_ptr(queue->ci);

/* Clear CQ entry ready bit */
- cq_base[cq->ci] &= ~CQ_ENTRY_READY_MASK;
+ cq_entry->data = cpu_to_le32(le32_to_cpu(cq_entry->data) &
+ ~CQ_ENTRY_READY_MASK);

cq->ci = hl_cq_inc_ptr(cq->ci);

--
2.20.1