Re: [PATCH v1 RFC 6/7] Add MIB counter reading support

Florian Fainelli
2017-10-09T20:07:44Z

On 10/06/2017 01:33 PM, Tristram.Ha@microchip.com wrote:
> From: Tristram Ha <Tristram.Ha@microchip.com>
>
> Add MIB counter reading support.
> Rename ksz_9477_reg.h to ksz9477_reg.h for consistency as the product
> name is always KSZ####.
> Header file ksz_priv.h no longer contains any chip specific data.

You should probably explain in the commit message that you are adding a
timer that reads counters every 30 seconds to avoid overflows, as this
is a pretty important piece of information.

> +static void ksz9477_phy_setup(struct ksz_device *dev, int port,
> + struct phy_device *phy)
> +{
> + if (port < dev->phy_port_cnt) {
> + /* SUPPORTED_Asym_Pause and SUPPORTED_Pause can be removed to
> + * disable flow control when rate limiting is used.
> + */
> + phy->advertising = phy->supported;
> + }
> +}

This appears to be an unrelated change here that you would want to put
in a separate patch.

> +
> static void ksz9477_port_setup(struct ksz_device *dev, int port, bool cpu_port)
> {
> u8 data8;
> @@ -1159,6 +1198,8 @@ static int ksz9477_setup(struct dsa_switch *ds)
> /* start switch */
> ksz_cfg(dev, REG_SW_OPERATION, SW_START, true);
>
> + ksz_init_mib_timer(dev);
> +
> return 0;
> }
>
> @@ -1168,6 +1209,7 @@ static int ksz9477_setup(struct dsa_switch *ds)
> .set_addr = ksz9477_set_addr,
> .phy_read = ksz9477_phy_read16,
> .phy_write = ksz9477_phy_write16,
> + .adjust_link = ksz_adjust_link,
> .port_enable = ksz_enable_port,
> .port_disable = ksz_disable_port,
> .get_strings = ksz9477_get_strings,
> @@ -1289,6 +1331,7 @@ static int ksz9477_switch_init(struct ksz_device *dev)
> if (!dev->ports)
> return -ENOMEM;
> for (i = 0; i < dev->mib_port_cnt; i++) {
> + mutex_init(&dev->ports[i].mib.cnt_mutex);
> dev->ports[i].mib.counters =
> devm_kzalloc(dev->dev,
> sizeof(u64) *
> @@ -1310,7 +1353,12 @@ static void ksz9477_switch_exit(struct ksz_device *dev)
> .get_port_addr = ksz9477_get_port_addr,
> .cfg_port_member = ksz9477_cfg_port_member,
> .flush_dyn_mac_table = ksz9477_flush_dyn_mac_table,
> + .phy_setup = ksz9477_phy_setup,
> .port_setup = ksz9477_port_setup,
> + .r_mib_cnt = ksz9477_r_mib_cnt,
> + .r_mib_pkt = ksz9477_r_mib_pkt,
> + .freeze_mib = ksz9477_freeze_mib,
> + .port_init_cnt = ksz9477_port_init_cnt,
> .shutdown = ksz9477_reset_switch,
> .detect = ksz9477_switch_detect,
> .init = ksz9477_switch_init,
> diff --git a/drivers/net/dsa/microchip/ksz_9477_reg.h b/drivers/net/dsa/microchip/ksz9477_reg.h
> similarity index 100%
> rename from drivers/net/dsa/microchip/ksz_9477_reg.h
> rename to drivers/net/dsa/microchip/ksz9477_reg.h
> diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
> index 1c9c4c5..885b3e3 100644
> --- a/drivers/net/dsa/microchip/ksz_common.c
> +++ b/drivers/net/dsa/microchip/ksz_common.c
> @@ -50,6 +50,81 @@ void ksz_update_port_member(struct ksz_device *dev, int port)
> }
> }
>
> +static void port_r_cnt(struct ksz_device *dev, int port)
> +{
> + struct ksz_port_mib *mib = &dev->ports[port].mib;
> + u64 *dropped;
> +
> + /* Some ports may not have MIB counters before SWITCH_COUNTER_NUM. */
> + while (mib->cnt_ptr < dev->reg_mib_cnt) {
> + dev->dev_ops->r_mib_cnt(dev, port, mib->cnt_ptr,
> + &mib->counters[mib->cnt_ptr]);
> + ++mib->cnt_ptr;
> + }
> +
> + /* last one in storage */
> + dropped = &mib->counters[dev->mib_cnt];
> +
> + /* Some ports may not have MIB counters after SWITCH_COUNTER_NUM. */
> + while (mib->cnt_ptr < dev->mib_cnt) {
> + dev->dev_ops->r_mib_pkt(dev, port, mib->cnt_ptr,
> + dropped, &mib->counters[mib->cnt_ptr]);
> + ++mib->cnt_ptr;
> + }
> + mib->cnt_ptr = 0;
> +}
> +
> +static void ksz_mib_read_work(struct work_struct *work)
> +{
> + struct ksz_device *dev =
> + container_of(work, struct ksz_device, mib_read);
> + struct ksz_port *p;
> + struct ksz_port_mib *mib;
> + int i;
> +
> + for (i = 0; i < dev->mib_port_cnt; i++) {
> + p = &dev->ports[i];
> + if (!p->on)
> + continue;
> + mib = &p->mib;
> + mutex_lock(&mib->cnt_mutex);
> +
> + /* read only dropped counters when link is not up */
> + if (p->link_down)
> + p->link_down = 0;
> + else if (!p->link_up)
> + mib->cnt_ptr = dev->reg_mib_cnt;

Can't you just check the ports' PHY device here instead of caching that
(which can get out of sync)?

> +void ksz_adjust_link(struct dsa_switch *ds, int port,
> + struct phy_device *phydev)
> +{
> + struct ksz_device *dev = ds->priv;
> + struct ksz_port *p = &dev->ports[port];
> +
> + if (phydev->link) {
> + p->speed = phydev->speed;
> + p->duplex = phydev->duplex;
> + p->flow_ctrl = phydev->pause;
> + p->link_up = 1;
> + dev->live_ports |= (1 << port) & dev->on_ports;
> + } else if (p->link_up) {
> + p->link_up = 0;
> + p->link_down = 1;
> + dev->live_ports &= ~(1 << port);
> + }
> +}

It would have been nice to explain why this is needed in the commit
message. dev->live_ports is read-only it seems?
--
Florian