Re: [net-next PATCH v3 02/14] net: dsa: qca8k: make mib autocast feature optional

Vladimir Oltean
2022-07-24T22:33:56Z

On Sat, Jul 23, 2022 at 04:18:33PM +0200, Christian Marangi wrote:
> Some switch may not support mib autocast feature and require the legacy
> way of reading the regs directly.
> Make the mib autocast feature optional and permit to declare support for
> it using match_data struct in a dedicated qca8k_info_ops struct.
>
> Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
> ---
> drivers/net/dsa/qca/qca8k.c | 11 +++++++++--
> drivers/net/dsa/qca/qca8k.h | 5 +++++
> 2 files changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/dsa/qca/qca8k.c b/drivers/net/dsa/qca/qca8k.c
> index 212b284f9f73..9820c5942d2a 100644
> --- a/drivers/net/dsa/qca/qca8k.c
> +++ b/drivers/net/dsa/qca/qca8k.c
> @@ -2104,8 +2104,8 @@ qca8k_get_ethtool_stats(struct dsa_switch *ds, int port,
> u32 hi = 0;
> int ret;
>
> - if (priv->mgmt_master &&
> - qca8k_get_ethtool_stats_eth(ds, port, data) > 0)
> + if (priv->mgmt_master && priv->info->ops.autocast_mib &&
> + priv->info->ops.autocast_mib(ds, port, data) > 0)
> return;
>
> for (i = 0; i < priv->info->mib_count; i++) {
> @@ -3248,20 +3248,27 @@ static int qca8k_resume(struct device *dev)
> static SIMPLE_DEV_PM_OPS(qca8k_pm_ops,
> qca8k_suspend, qca8k_resume);
>
> +static const struct qca8k_info_ops qca8xxx_ops = {
> + .autocast_mib = qca8k_get_ethtool_stats_eth,
> +};
> +
> static const struct qca8k_match_data qca8327 = {
> .id = QCA8K_ID_QCA8327,
> .reduced_package = true,
> .mib_count = QCA8K_QCA832X_MIB_COUNT,
> + .ops = qca8xxx_ops,
> };
>
> static const struct qca8k_match_data qca8328 = {
> .id = QCA8K_ID_QCA8327,
> .mib_count = QCA8K_QCA832X_MIB_COUNT,
> + .ops = qca8xxx_ops,
> };
>
> static const struct qca8k_match_data qca833x = {
> .id = QCA8K_ID_QCA8337,
> .mib_count = QCA8K_QCA833X_MIB_COUNT,
> + .ops = qca8xxx_ops,
> };
>
> static const struct of_device_id qca8k_of_match[] = {
> diff --git a/drivers/net/dsa/qca/qca8k.h b/drivers/net/dsa/qca/qca8k.h
> index 0b990b46890a..7b4a698f092a 100644
> --- a/drivers/net/dsa/qca/qca8k.h
> +++ b/drivers/net/dsa/qca/qca8k.h
> @@ -324,10 +324,15 @@ enum qca8k_mid_cmd {
> QCA8K_MIB_CAST = 3,
> };
>
> +struct qca8k_info_ops {
> + int (*autocast_mib)(struct dsa_switch *ds, int port, u64 *data);
> +};
> +
> struct qca8k_match_data {
> u8 id;
> bool reduced_package;
> u8 mib_count;
> + struct qca8k_info_ops ops;

This creates a copy of the structure for each of qca8327, qca8328, etc etc,
which in turn will consume 3 times more space than necessary when new
ops are added. Could you make this "const struct qca8k_ops *ops"?

> };
>
> enum {
> --
> 2.36.1
>