Re: [PATCH v1 1/7] e1000: add rx interrupt support

["Liang, Cunming" <cunming.liang@intel.com>]

Hi Yong,

On 9/25/2015 4:28 PM, Yong Liu wrote:
> From: Marvin Liu <yong.liu@intel.com>
>
> Enable rx interrupt support on e1000 PF non-IOV mode.
As I know, e1000 hasn't IOV mode. It's not necessary to mention PF 
non-IOV mode or not.
In addition, it's necessary to mention the patch series is to support 
uio/vfio or both? To allow physical/emulation or both?
>
> Signed-off-by: Marvin Liu <yong.liu@intel.com>
>
> diff --git a/drivers/net/e1000/em_ethdev.c b/drivers/net/e1000/em_ethdev.c
> index 912f5dd..99beb9c 100644
> --- a/drivers/net/e1000/em_ethdev.c
> +++ b/drivers/net/e1000/em_ethdev.c
> @@ -81,6 +81,7 @@ static int eth_em_flow_ctrl_get(struct rte_eth_dev *dev,
>   static int eth_em_flow_ctrl_set(struct rte_eth_dev *dev,
>   				struct rte_eth_fc_conf *fc_conf);
>   static int eth_em_interrupt_setup(struct rte_eth_dev *dev);
> +static int eth_em_rxq_interrupt_setup(struct rte_eth_dev *dev);
>   static int eth_em_interrupt_get_status(struct rte_eth_dev *dev);
>   static int eth_em_interrupt_action(struct rte_eth_dev *dev);
>   static void eth_em_interrupt_handler(struct rte_intr_handle *handle,
> @@ -107,6 +108,7 @@ static void em_vlan_hw_strip_disable(struct rte_eth_dev *dev);
>   static void eth_em_vlan_filter_set(struct rte_eth_dev *dev,
>   					uint16_t vlan_id, int on);
>   */
> +static void em_rxq_intr_enable(struct e1000_hw *hw);
>   static int eth_em_led_on(struct rte_eth_dev *dev);
>   static int eth_em_led_off(struct rte_eth_dev *dev);
>   
> @@ -608,6 +610,9 @@ eth_em_start(struct rte_eth_dev *dev)
>   			return ret;
>   		}
>   	}
> +	/* check if rxq interrupt is enabled */
> +	if (dev->data->dev_conf.intr_conf.rxq != 0)
> +		eth_em_rxq_interrupt_setup(dev);
>   
>   	adapter->stopped = 0;
>   
> @@ -1276,6 +1281,39 @@ eth_em_interrupt_setup(struct rte_eth_dev *dev)
>   	return (0);
>   }
>   
> +/* It clears the interrupt causes and enables the interrupt.
Comments start from next line of '/*' or '/**'?
> + * It will be called once only during nic initialized.
> + *
> + * @param dev
> + *  Pointer to struct rte_eth_dev.
> + *
> + * @return
> + *  - On success, zero.
> + *  - On failure, a negative value.
> + */
> +static int
> +eth_em_rxq_interrupt_setup(struct rte_eth_dev *dev)
> +{
> +	struct e1000_hw *hw =
> +	E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);
> +
> +	E1000_READ_REG(hw, E1000_ICR);
> +	em_rxq_intr_enable(hw);
> +	return 0;
> +}
> +
> +/* It enable receive packet interrupt.
The same.
> + * @param hw
> + * Pointer to struct e1000_hw
> + *
> + * @return
> + */
> +static void
> +em_rxq_intr_enable(struct e1000_hw *hw)
> +{
> +	E1000_WRITE_REG(hw, E1000_IMS, E1000_IMS_RXT0);
To make sure post-write be finished immediately, E1000_WRITE_FLUSH() 
shall add behind.
> +}
> +
>   /*
>    * It reads ICR and gets interrupt causes, check it and set a bit flag
>    * to update link status.