Re: [PATCH v8 net-next 09/11] net: ethernet: ti: am65-cpsw-qos: Add Frame Preemption MAC Merge support

[Roger Quadros <rogerq@kernel.org>]

On 14/12/2023 13:04, Vladimir Oltean wrote:
> On Wed, Dec 13, 2023 at 01:07:19PM +0200, Roger Quadros wrote:
>> - Fix am65_cpsw_iet_get_verify_timeout_ms() to default to timeout for
>>   1G link if link is inactive.
>> +
>> +static int am65_cpsw_set_mm(struct net_device *ndev, struct ethtool_mm_cfg *cfg,
>> +			    struct netlink_ext_ack *extack)
>> +{
>> +	val = readl(port->port_base + AM65_CPSW_PN_REG_IET_CTRL);
>> +	if (cfg->verify_enabled) {
>> +		val &= ~AM65_CPSW_PN_IET_MAC_DISABLEVERIFY;
>> +		/* Reset Verify state machine. Verification won't start here.
>> +		 * Verification will be done once link-up.
>> +		 */
>> +		val |= AM65_CPSW_PN_IET_MAC_LINKFAIL;
>> +	} else {
>> +		val |= AM65_CPSW_PN_IET_MAC_DISABLEVERIFY;
>> +		/* Clear LINKFAIL to allow verify/response packets */
>> +		val &= ~AM65_CPSW_PN_IET_MAC_LINKFAIL;
>> +	}
>> +
>> +	val &= ~AM65_CPSW_PN_IET_MAC_MAC_ADDFRAGSIZE_MASK;
>> +	val |= AM65_CPSW_PN_IET_MAC_SET_ADDFRAGSIZE(add_frag_size);
>> +	writel(val, port->port_base + AM65_CPSW_PN_REG_IET_CTRL);
>> +
>> +	/* verify_timeout_count can only be set at valid link */
>> +	if (cfg->verify_time > 0)
>> +		port->qos.iet.verify_time_ms = cfg->verify_time;
>> +	else
>> +		port->qos.iet.verify_time_ms = 10;
> 
> I don't think I understand what the check is for? The netlink policy for
> ETHTOOL_A_MM_VERIFY_TIME limits the range between 1 ms and 128 ms.
> How can it be 0?

I didn't check ETHTOOL_A_MM_VERIFY_TIME before.
Indeed, this check is pointless.

> 
>> +
>> +	/* enable/disable preemption based on link status */
>> +	am65_cpsw_iet_commit_preemptible_tcs(port);
>> +
>> +	return 0;
>> +}

-- 
cheers,
-roger