Re: [dpdk-dev] [PATCH 4/4] net/hns3: fix FEC state query

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 11/20/2020 11:27 AM, Lijun Ou wrote:
> From: "Min Hu (Conor)" <humin29@huawei.com>
> 
> As FEC is not supported below 10 Gbps, CMD(0x031A) offered
> from Firmware read will return fail in 10 Gbps device.
> 
> This patch will prevent read this CMD when below 10 Gbps,
> as this is non-sense.
> 
> Fixes: 9bf2ea8dbc65 ("net/hns3: support FEC")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Min Hu (Connor) <humin29@huawei.com>
> Signed-off-by: Lijun Ou <oulijun@huawei.com>
> ---
>   drivers/net/hns3/hns3_ethdev.c | 38 ++++++++++++++++++++++++--------------
>   1 file changed, 24 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/net/hns3/hns3_ethdev.c b/drivers/net/hns3/hns3_ethdev.c
> index d6d3f03..faa7b0a 100644
> --- a/drivers/net/hns3/hns3_ethdev.c
> +++ b/drivers/net/hns3/hns3_ethdev.c
> @@ -100,7 +100,7 @@ static int hns3_add_mc_addr(struct hns3_hw *hw,
>   static int hns3_remove_mc_addr(struct hns3_hw *hw,
>   			    struct rte_ether_addr *mac_addr);
>   static int hns3_restore_fec(struct hns3_hw *hw);
> -static int hns3_query_dev_fec_info(struct rte_eth_dev *dev);
> +static int hns3_query_dev_fec_info(struct hns3_hw *hw);
>   
>   void hns3_ether_format_addr(char *buf, uint16_t size,
>   			    const struct rte_ether_addr *ether_addr)
> @@ -3010,13 +3010,6 @@ hns3_get_capability(struct hns3_hw *hw)
>   	    device_id == HNS3_DEV_ID_200G_RDMA)
>   		hns3_set_bit(hw->capability, HNS3_DEV_SUPPORT_DCB_B, 1);
>   
> -	ret = hns3_query_dev_fec_info(eth_dev);
> -	if (ret) {
> -		PMD_INIT_LOG(ERR,
> -			     "failed to query FEC information, ret = %d", ret);
> -		return ret;
> -	}
> -
>   	/* Get PCI revision id */
>   	ret = rte_pci_read_config(pci_dev, &revision, HNS3_PCI_REVISION_ID_LEN,
>   				  HNS3_PCI_REVISION_ID);
> @@ -3148,8 +3141,15 @@ hns3_get_configuration(struct hns3_hw *hw)
>   	}
>   
>   	ret = hns3_get_board_configuration(hw);
> -	if (ret)
> +	if (ret) {
>   		PMD_INIT_LOG(ERR, "failed to get board configuration: %d", ret);
> +		return ret;
> +	}
> +
> +	ret = hns3_query_dev_fec_info(hw);
> +	if (ret)
> +		PMD_INIT_LOG(ERR,
> +			     "failed to query FEC information, ret = %d", ret);
>   
>   	return ret;
>   }
> @@ -5797,6 +5797,15 @@ get_current_fec_auto_state(struct hns3_hw *hw, uint8_t *state)
>   	struct hns3_cmd_desc desc;
>   	int ret;
>   
> +	/*
> +	 * CMD(0x031A) read is not supported in device of link speed
> +	 * below 10 Gbps.
> +	 */
> +	if (hw->mac.link_speed < ETH_SPEED_NUM_10G) {
> +		*state = 0;
> +		return 0;
> +	}
> +
>   	hns3_cmd_setup_basic_desc(&desc, HNS3_OPC_CONFIG_FEC_MODE, true);
>   	req = (struct hns3_config_fec_cmd *)desc.data;
>   	ret = hns3_cmd_send(hw, &desc, 1);
> @@ -6003,14 +6012,15 @@ hns3_restore_fec(struct hns3_hw *hw)
>   }
>   
>   static int
> -hns3_query_dev_fec_info(struct rte_eth_dev *dev)
> +hns3_query_dev_fec_info(struct hns3_hw *hw)
>   {
> -	struct hns3_adapter *hns = dev->data->dev_private;
> -	struct hns3_hw *hw = HNS3_DEV_PRIVATE_TO_HW(hns);
> -	struct hns3_pf *pf = &hns->pf;
> +	struct hns3_adapter *hns = HNS3_DEV_HW_TO_ADAPTER(hw);
> +	struct hns3_pf *pf = HNS3_DEV_PRIVATE_TO_PF(hns);
> +	struct rte_eth_dev *eth_dev;
>   	int ret;
>   
> -	ret = hns3_fec_get(dev, &pf->fec_mode);
> +	eth_dev = &rte_eth_devices[hw->data->port_id];

Not specific to this patch, but it is not good idea to access global 
'rte_eth_devices' array directly. Why not store the 'eth_dev' in the device 
private data in the probe() and use it later?
Can you do a separate patch for this switch?
Thank you may not need to change the paramters of the 
'hns3_query_dev_fec_info()' or remove it from 'hns3_query_dev_fec_info()' since 
you will be able to access to 'eth_dev' easily.

> +	ret = hns3_fec_get(eth_dev, &pf->fec_mode);
>   	if (ret)
>   		hns3_err(hw, "query device FEC info failed, ret = %d", ret);
>   
>