[dpdk-stable] [PATCH 19.11 6/6] net/hns3: fix MSI-X interrupt during initialization

["Wei Hu (Xavier)" <xavier.huwei@huawei.com>]

[ upstream commit 2de74dcfbd150fde59c8e0a20ae21e22ab27605e ]

Currently, based on hns3 VF device error may occur during initialization.

The root cause as below:
When the following formula is executed during initialization, the
private variable named hw->tqps_num has not been obtained from PF driver
through mailbox, further causes failure when mapping interrupt and
queues.
  hw->num_msi = (num_msi > hw->tqps_num + 1) ? hw->tqps_num + 1 : num_msi;
We need to use hw->tqp_num after it is correctly assigned.

On the other hand, because the private variable named hw->num_msi, which
represents the number of MSI-x interrupt of hns3 PF/VF device, is used in
the '.get_reg' ops implementation function to dump all interrupt related
registers, it should be obtained from firmware directly and we'd better
not modify it in the driver.

Fixes: ef2e785c36cf ("net/hns3: fix Tx interrupt when enabling Rx interrupt")
Fixes: 02a7b55657b2 ("net/hns3: support Rx interrupt")
Cc: stable@dpdk.org

Signed-off-by: Wei Hu (Xavier) <xavier.huwei@huawei.com>
Signed-off-by: Hao Chen <chenhao164@huawei.com>
Signed-off-by: Min Hu (Connor) <humin29@huawei.com>
---
 drivers/net/hns3/hns3_ethdev.c    | 10 +++++-----
 drivers/net/hns3/hns3_ethdev_vf.c |  5 +++--
 2 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/drivers/net/hns3/hns3_ethdev.c b/drivers/net/hns3/hns3_ethdev.c
index c693913..3271b61 100644
--- a/drivers/net/hns3/hns3_ethdev.c
+++ b/drivers/net/hns3/hns3_ethdev.c
@@ -2150,7 +2150,8 @@ hns3_init_ring_with_vector(struct hns3_hw *hw)
 	 * Rx interrupt.
 	 */
 	vec = hw->num_msi - 1; /* vector 0 for misc interrupt, not for queue */
-	hw->intr_tqps_num = vec - 1; /* the last interrupt is reserved */
+	/* vec - 1: the last interrupt is reserved */
+	hw->intr_tqps_num = vec > hw->tqps_num ? hw->tqps_num : vec - 1;
 	for (i = 0; i < hw->intr_tqps_num; i++) {
 		/*
 		 * Set gap limiter and rate limiter configuration of queue's
@@ -2523,7 +2524,6 @@ hns3_query_pf_resource(struct hns3_hw *hw)
 	struct hns3_pf *pf = &hns->pf;
 	struct hns3_pf_res_cmd *req;
 	struct hns3_cmd_desc desc;
-	uint16_t num_msi;
 	int ret;
 
 	hns3_cmd_setup_basic_desc(&desc, HNS3_OPC_QUERY_PF_RSRC, true);
@@ -2555,9 +2555,9 @@ hns3_query_pf_resource(struct hns3_hw *hw)
 
 	pf->dv_buf_size = roundup(pf->dv_buf_size, HNS3_BUF_SIZE_UNIT);
 
-	num_msi = hns3_get_field(rte_le_to_cpu_16(req->pf_intr_vector_number),
-				 HNS3_VEC_NUM_M, HNS3_VEC_NUM_S);
-	hw->num_msi = (num_msi > hw->tqps_num + 1) ? hw->tqps_num + 1 : num_msi;
+	hw->num_msi =
+	    hns3_get_field(rte_le_to_cpu_16(req->pf_intr_vector_number),
+			   HNS3_VEC_NUM_M, HNS3_VEC_NUM_S);
 
 	return 0;
 }
diff --git a/drivers/net/hns3/hns3_ethdev_vf.c b/drivers/net/hns3/hns3_ethdev_vf.c
index 11d7dea..251d0ef 100644
--- a/drivers/net/hns3/hns3_ethdev_vf.c
+++ b/drivers/net/hns3/hns3_ethdev_vf.c
@@ -472,7 +472,8 @@ hns3vf_init_ring_with_vector(struct hns3_hw *hw)
 	 * Rx interrupt.
 	 */
 	vec = hw->num_msi - 1; /* vector 0 for misc interrupt, not for queue */
-	hw->intr_tqps_num = vec - 1; /* the last interrupt is reserved */
+	/* vec - 1: the last interrupt is reserved */
+	hw->intr_tqps_num = vec > hw->tqps_num ? hw->tqps_num : vec - 1;
 	for (i = 0; i < hw->intr_tqps_num; i++) {
 		/*
 		 * Set gap limiter and rate limiter configuration of queue's
@@ -1203,7 +1204,7 @@ hns3_query_vf_resource(struct hns3_hw *hw)
 		return -EINVAL;
 	}
 
-	hw->num_msi = (num_msi > hw->tqps_num + 1) ? hw->tqps_num + 1 : num_msi;
+	hw->num_msi = num_msi;
 
 	return 0;
 }
-- 
2.7.4