Re: [PATCH RESEND v4 net-next 13/14] net: enetc: use alloc_etherdev_mqs() to create netdev for VF driver
From: Joe Damato
Date: Mon Jul 20 2026 - 13:41:48 EST
On Mon, Jul 20, 2026 at 09:43:15AM +0800, wei.fang@xxxxxxxxxxx wrote:
> From: Wei Fang <wei.fang@xxxxxxx>
>
> The VF driver uses alloc_etherdev_mq() with ENETC_MAX_NUM_TXQS as the
> queue count, which forces the TX and RX queue counts to be equal and
> uses a compile-time constant rather than the actual hardware capability.
>
> After enetc_get_si_caps() is called, si->num_tx_rings and
> si->num_rx_rings reflect the actual number of rings assigned to the VF
> by the PF. For the ENETC VF on LS1028A and the upcoming i.MX95/94, their
> SoCs have no more than 6 CPUs, and the number of TX/RX rings allocated
> to the VF is less than 8.
>
> Therefore, switch to alloc_etherdev_mqs() so that the TX and RX queue
> counts are set independently, each capped at ENETC_MAX_NUM_TXQS, based
> on the actual number of rings assigned to the VF by the PF.
>
> Note that if future SoCs have more than 6 CPUs and more than 6 RX rings
> allocated to VFs, the size of the int_vector array in struct
> enetc_ndev_priv will need to be modified. Similarly, if more than 8 TX
> rings are allocated to each int_vector, ENETC_MAX_NUM_TXQS will also
> need to be modified.
>
> Signed-off-by: Wei Fang <wei.fang@xxxxxxx>
> ---
> drivers/net/ethernet/freescale/enetc/enetc_vf.c | 9 ++++++++-
> 1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/freescale/enetc/enetc_vf.c b/drivers/net/ethernet/freescale/enetc/enetc_vf.c
> index 9cdb0a4d6baf..7dcb4a0246f5 100644
> --- a/drivers/net/ethernet/freescale/enetc/enetc_vf.c
> +++ b/drivers/net/ethernet/freescale/enetc/enetc_vf.c
> @@ -317,7 +317,14 @@ static int enetc_vf_probe(struct pci_dev *pdev,
>
> enetc_get_si_caps(si);
>
> - ndev = alloc_etherdev_mq(sizeof(*priv), ENETC_MAX_NUM_TXQS);
> + /* Currently, the supported SoCs have a max of 6 CPUs and the VFs
> + * have less than 6 RX/TX rings. So no issues for these supported
> + * SoCs, but for future SoCs which have more CPUs or more TX/RX
> + * rings, all the related logic needs to be improved.
> + */
> + ndev = alloc_etherdev_mqs(sizeof(*priv),
> + min(si->num_tx_rings, ENETC_MAX_NUM_TXQS),
> + min(si->num_rx_rings, ENETC_MAX_NUM_TXQS));
Code looks right, but looks almost like a typo. I guess it would read nicer if
ENETC_MAX_NUM_RXQS existed?
That said:
Reviewed-by: Joe Damato <joe@xxxxxxx>