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From: Gavin Hu <gavin.hu@arm.com>
To: dev@dpdk.org
Cc: nd@arm.com, thomas@monjalon.net, bruce.richardson@intel.com,
	yong.liu@intel.com, yinan.wang@intel.com,
	ajit.khaparde@broadcom.com, somnath.kotur@broadcom.com,
	Honnappa.Nagarahalli@arm.com, ruifeng.wang@arm.com,
	steve.capper@arm.com, stable@dpdk.org
Subject: [dpdk-dev] [PATCH v2 5/5] net/bnxt: enforce io barrier for doorbell command
Date: Mon, 16 Sep 2019 19:27:18 +0800	[thread overview]
Message-ID: <1568633238-47888-6-git-send-email-gavin.hu@arm.com> (raw)
In-Reply-To: <1568633238-47888-1-git-send-email-gavin.hu@arm.com>
In-Reply-To: <1567751873-15964-1-git-send-email-gavin.hu@arm.com>

The doorbell ringing operation requires a rte_io_mb immediately to make
the command complete and visible to the device before reading the
response, otherwise it may read stale or invalid responses.

Fixes: ca241d9a0952 ("net/bnxt: use I/O device memory read/write API")
Cc: stable@dpdk.org

Signed-off-by: Gavin Hu <gavin.hu@arm.com>
---
 drivers/net/bnxt/bnxt_hwrm.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/net/bnxt/bnxt_hwrm.c b/drivers/net/bnxt/bnxt_hwrm.c
index 2d5dc00..7d192e3 100644
--- a/drivers/net/bnxt/bnxt_hwrm.c
+++ b/drivers/net/bnxt/bnxt_hwrm.c
@@ -134,6 +134,12 @@ static int bnxt_hwrm_send_message(struct bnxt *bp, void *msg,
 	/* Ring channel doorbell */
 	bar = (uint8_t *)bp->bar0 + mb_trigger_offset;
 	rte_write32(1, bar);
+	/*
+	 * Make sure the channel doorbell ring command complete before
+	 * reading the response to avoid getting stale or invalid
+	 * responses.
+	 */
+	rte_io_mb();
 
 	/* Poll for the valid bit */
 	for (i = 0; i < HWRM_CMD_TIMEOUT; i++) {
-- 
2.7.4


  parent reply	other threads:[~2019-09-16 11:28 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-09-06  6:37 [dpdk-dev] [PATCH] net/bnxt: fix memory barriers Gavin Hu
2019-09-16 11:27 ` [dpdk-dev] [PATCH v2 0/5] fix and optimize barriers usage with some PMDs Gavin Hu
2019-10-02 17:41   ` Ferruh Yigit
2019-09-16 11:27 ` [dpdk-dev] [PATCH v2 1/5] net/i40e: use relaxed and remove duplicate barrier Gavin Hu
2019-09-17  1:53   ` Zhang, Qi Z
2019-09-17  2:07     ` Gavin Hu (Arm Technology China)
2019-09-17  3:23       ` Gavin Hu (Arm Technology China)
2019-09-17  5:13         ` Zhang, Qi Z
2019-09-16 11:27 ` [dpdk-dev] [PATCH v2 2/5] net/ice: " Gavin Hu
2019-09-17  1:51   ` Zhang, Qi Z
2019-09-16 11:27 ` [dpdk-dev] [PATCH v2 3/5] net/bnxt: " Gavin Hu
2019-09-17  1:55   ` Ajit Khaparde
2019-09-16 11:27 ` [dpdk-dev] [PATCH v2 4/5] net/bnxt: replace with cio barrier for doorbell resp Gavin Hu
2019-09-17  1:56   ` Ajit Khaparde
2019-09-16 11:27 ` Gavin Hu [this message]
2019-09-17  1:55   ` [dpdk-dev] [PATCH v2 5/5] net/bnxt: enforce io barrier for doorbell command Ajit Khaparde

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