[PATCH 30/46] common/sfc_efx/base: implement PHY link control for Medford4

[Andrew Rybchenko]

On 4/16/25 17:00, Ivan Malov wrote:
> Use new MCDI to select loopback, speed, flow control and FEC.
> 
> Signed-off-by: Ivan Malov <ivan.malov at arknetworks.am>
> Reviewed-by: Andy Moreton <andy.moreton at amd.com>
> Reviewed-by: Pieter Jansen Van Vuuren <pieter.jansen-van-vuuren at amd.com>

[snip]

> +static					void
> +efx_np_cap_sw_mask_to_hw_enum(
> +	__in_ecount(hw_sw_map_nentries)	const struct efx_np_cap_map *hw_sw_map,
> +	__in				unsigned int hw_sw_map_nentries,
> +	__in_bcount(hw_cap_data_nbytes)	const uint8_t *hw_cap_data,
> +	__in				size_t hw_cap_data_nbytes,
> +	__in				uint32_t mask_sw,
> +	__out				boolean_t *supportedp,
> +	__out_opt			uint16_t *enum_hwp)
> +{
> +	unsigned int sw_nflags_req = 0;
> +	unsigned int sw_nflags_sup = 0;
> +	uint32_t sw_check_mask = 0;
> +	unsigned int i;
> +
> +	for (i = 0; i < hw_sw_map_nentries; ++i) {
> +		uint32_t flag_sw = 1U << hw_sw_map->encm_sw;
> +		unsigned int byte_idx = CAP_BYTE(hw_sw_map);
> +		uint8_t flag_hw = CAP_FLAG(hw_sw_map);
> +
> +		if (byte_idx >= hw_cap_data_nbytes) {
> +			++(hw_sw_map);
> +			continue;
> +		}
> +
> +		if ((mask_sw & flag_sw) == flag_sw) {
> +			if ((sw_check_mask & flag_sw) == 0)
> +				++(sw_nflags_req);
> +
> +			sw_check_mask |= flag_sw;
> +
> +			if ((hw_cap_data[byte_idx] & flag_hw) == flag_hw) {
> +				mask_sw &= ~(flag_sw);
> +
> +				if (enum_hwp != NULL)
> +					*enum_hwp = hw_sw_map->encm_hw;
> +			}
> +		}
> +
> +		++(hw_sw_map);
> +	}
> +
> +	/*
> +	 * FIXME: in the absence of autonegotiation capability, drivers
> +	 * may still pass multiple capability bits of the same category.
> +	 * That is supposed to work on EF10; do not enforce below check.
> +	 */
> +#if 0

It looks rather strange when code with #if 0 comes.

> +	if (sw_nflags_req != 1) {
> +		/*
> +		 * The mask must contain exactly one relevant
> +		 * flag which represents some specific choice.
> +		 */
> +		*supportedp = B_FALSE;
> +		return;
> +	}
> +#endif
> +
> +	if (sw_check_mask != 0 && (mask_sw & sw_check_mask) == sw_check_mask) {
> +		/* Failed to select the enum by at least one capability bit. */
> +		*supportedp = B_FALSE;
> +		return;
> +	}
> +
> +	*supportedp = B_TRUE;
> +}

[snip]