From: Xi Wang <wangxi11@huawei.com>
Date: Wed, 6 Jun 2018 14:07:53 +0100
Subject: net: hns3: Optimize PF CMDQ interrupt switching process
Patch-mainline: v4.18-rc1
Git-commit: 8e52a602b5126183f7a6487c4d48f6a00af4e4fd
References: bsc#1104353 FATE#326415

When the PF frequently switches the CMDQ interrupt, if the CMDQ_SRC is
not cleared before the hardware interrupt is generated, the new interrupt
will not be reported.

This patch optimizes this problem by clearing CMDQ_SRC and RESET_STS
before enabling interrupt and syncing pending IRQ handlers after disabling
interrupt.

Fixes: 466b0c00391b ("net: hns3: Add support for misc interrupt")
Signed-off-by: Xi Wang <wangxi11@huawei.com>
Signed-off-by: Peng Li <lipeng321@huawei.com>
Signed-off-by: Salil Mehta <salil.mehta@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c |   13 +++++++++++++
 1 file changed, 13 insertions(+)

--- a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c
@@ -2557,6 +2557,15 @@ static void hclge_clear_event_cause(stru
 	}
 }
 
+static void hclge_clear_all_event_cause(struct hclge_dev *hdev)
+{
+	hclge_clear_event_cause(hdev, HCLGE_VECTOR0_EVENT_RST,
+				BIT(HCLGE_VECTOR0_GLOBALRESET_INT_B) |
+				BIT(HCLGE_VECTOR0_CORERESET_INT_B) |
+				BIT(HCLGE_VECTOR0_IMPRESET_INT_B));
+	hclge_clear_event_cause(hdev, HCLGE_VECTOR0_EVENT_MBX, 0);
+}
+
 static void hclge_enable_vector(struct hclge_misc_vector *vector, bool enable)
 {
 	writel(enable ? 1 : 0, vector->addr);
@@ -5689,6 +5698,8 @@ static int hclge_init_ae_dev(struct hnae
 	INIT_WORK(&hdev->rst_service_task, hclge_reset_service_task);
 	INIT_WORK(&hdev->mbx_service_task, hclge_mailbox_service_task);
 
+	hclge_clear_all_event_cause(hdev);
+
 	/* Enable MISC vector(vector0) */
 	hclge_enable_vector(&hdev->misc_vector, true);
 
@@ -5818,6 +5829,8 @@ static void hclge_uninit_ae_dev(struct h
 
 	/* Disable MISC vector(vector0) */
 	hclge_enable_vector(&hdev->misc_vector, false);
+	synchronize_irq(hdev->misc_vector.vector_irq);
+
 	hclge_destroy_cmd_queue(&hdev->hw);
 	hclge_misc_irq_uninit(hdev);
 	hclge_pci_uninit(hdev);