Re: [PATCH net-next V2 1/3] net: ethtool: Add support for 1600Gbps speed

[Maxime Chevallier <maxime.chevallier@bootlin.com>]

On 19/11/2025 21:48, Tariq Toukan wrote:
> From: Yael Chemla <ychemla@nvidia.com>
> 
> Add support for 1600Gbps link modes based on 200Gbps per lane [1].
> This includes the adopted IEEE 802.3dj copper and optical PMDs that use
> 200G/lane signaling [2].
> 
> Add the following PMD types:
> - KR8 (backplane)
> - CR8 (copper cable)
> - DR8 (SMF 500m)
> - DR8-2 (SMF 2km)
> 
> These modes are defined in the 802.3dj specifications.
> References:
> [1] https://www.ieee802.org/3/dj/public/23_03/opsasnick_3dj_01a_2303.pdf
> [2] https://www.ieee802.org/3/dj/projdoc/objectives_P802d3dj_240314.pdf
> 
> Signed-off-by: Yael Chemla <ychemla@nvidia.com>
> Reviewed-by: Shahar Shitrit <shshitrit@nvidia.com>
> Signed-off-by: Tariq Toukan <tariqt@nvidia.com>

Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>

Maxime

> ---
>  drivers/net/phy/phy-caps.h   | 1 +
>  drivers/net/phy/phy-core.c   | 4 +++-
>  drivers/net/phy/phy_caps.c   | 2 ++
>  include/uapi/linux/ethtool.h | 5 +++++
>  net/ethtool/common.c         | 8 ++++++++
>  5 files changed, 19 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/phy/phy-caps.h b/drivers/net/phy/phy-caps.h
> index b7f0c6a3037a..4951a39f3828 100644
> --- a/drivers/net/phy/phy-caps.h
> +++ b/drivers/net/phy/phy-caps.h
> @@ -29,6 +29,7 @@ enum {
>  	LINK_CAPA_200000FD,
>  	LINK_CAPA_400000FD,
>  	LINK_CAPA_800000FD,
> +	LINK_CAPA_1600000FD,
>  
>  	__LINK_CAPA_MAX,
>  };
> diff --git a/drivers/net/phy/phy-core.c b/drivers/net/phy/phy-core.c
> index 0c63e6ba2cb0..277c034bc32f 100644
> --- a/drivers/net/phy/phy-core.c
> +++ b/drivers/net/phy/phy-core.c
> @@ -17,7 +17,7 @@
>   */
>  const char *phy_speed_to_str(int speed)
>  {
> -	BUILD_BUG_ON_MSG(__ETHTOOL_LINK_MODE_MASK_NBITS != 121,
> +	BUILD_BUG_ON_MSG(__ETHTOOL_LINK_MODE_MASK_NBITS != 125,
>  		"Enum ethtool_link_mode_bit_indices and phylib are out of sync. "
>  		"If a speed or mode has been added please update phy_speed_to_str "
>  		"and the PHY settings array.\n");
> @@ -55,6 +55,8 @@ const char *phy_speed_to_str(int speed)
>  		return "400Gbps";
>  	case SPEED_800000:
>  		return "800Gbps";
> +	case SPEED_1600000:
> +		return "1600Gbps";
>  	case SPEED_UNKNOWN:
>  		return "Unknown";
>  	default:
> diff --git a/drivers/net/phy/phy_caps.c b/drivers/net/phy/phy_caps.c
> index 23c808b59b6f..3a05982b39bf 100644
> --- a/drivers/net/phy/phy_caps.c
> +++ b/drivers/net/phy/phy_caps.c
> @@ -25,6 +25,7 @@ static struct link_capabilities link_caps[__LINK_CAPA_MAX] __ro_after_init = {
>  	{ SPEED_200000, DUPLEX_FULL, {0} }, /* LINK_CAPA_200000FD */
>  	{ SPEED_400000, DUPLEX_FULL, {0} }, /* LINK_CAPA_400000FD */
>  	{ SPEED_800000, DUPLEX_FULL, {0} }, /* LINK_CAPA_800000FD */
> +	{ SPEED_1600000, DUPLEX_FULL, {0} }, /* LINK_CAPA_1600000FD */
>  };
>  
>  static int speed_duplex_to_capa(int speed, unsigned int duplex)
> @@ -52,6 +53,7 @@ static int speed_duplex_to_capa(int speed, unsigned int duplex)
>  	case SPEED_200000: return LINK_CAPA_200000FD;
>  	case SPEED_400000: return LINK_CAPA_400000FD;
>  	case SPEED_800000: return LINK_CAPA_800000FD;
> +	case SPEED_1600000: return LINK_CAPA_1600000FD;
>  	}
>  
>  	return -EINVAL;
> diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
> index 8bd5ea5469d9..eb7ff2602fbb 100644
> --- a/include/uapi/linux/ethtool.h
> +++ b/include/uapi/linux/ethtool.h
> @@ -2077,6 +2077,10 @@ enum ethtool_link_mode_bit_indices {
>  	ETHTOOL_LINK_MODE_800000baseDR4_2_Full_BIT	 = 118,
>  	ETHTOOL_LINK_MODE_800000baseSR4_Full_BIT	 = 119,
>  	ETHTOOL_LINK_MODE_800000baseVR4_Full_BIT	 = 120,
> +	ETHTOOL_LINK_MODE_1600000baseCR8_Full_BIT	 = 121,
> +	ETHTOOL_LINK_MODE_1600000baseKR8_Full_BIT	 = 122,
> +	ETHTOOL_LINK_MODE_1600000baseDR8_Full_BIT	 = 123,
> +	ETHTOOL_LINK_MODE_1600000baseDR8_2_Full_BIT	 = 124,
>  
>  	/* must be last entry */
>  	__ETHTOOL_LINK_MODE_MASK_NBITS
> @@ -2190,6 +2194,7 @@ enum ethtool_link_mode_bit_indices {
>  #define SPEED_200000		200000
>  #define SPEED_400000		400000
>  #define SPEED_800000		800000
> +#define SPEED_1600000		1600000
>  
>  #define SPEED_UNKNOWN		-1
>  
> diff --git a/net/ethtool/common.c b/net/ethtool/common.c
> index 55223ebc2a7e..369c05cf8163 100644
> --- a/net/ethtool/common.c
> +++ b/net/ethtool/common.c
> @@ -233,6 +233,10 @@ const char link_mode_names[][ETH_GSTRING_LEN] = {
>  	__DEFINE_LINK_MODE_NAME(800000, DR4_2, Full),
>  	__DEFINE_LINK_MODE_NAME(800000, SR4, Full),
>  	__DEFINE_LINK_MODE_NAME(800000, VR4, Full),
> +	__DEFINE_LINK_MODE_NAME(1600000, CR8, Full),
> +	__DEFINE_LINK_MODE_NAME(1600000, KR8, Full),
> +	__DEFINE_LINK_MODE_NAME(1600000, DR8, Full),
> +	__DEFINE_LINK_MODE_NAME(1600000, DR8_2, Full),
>  };
>  static_assert(ARRAY_SIZE(link_mode_names) == __ETHTOOL_LINK_MODE_MASK_NBITS);
>  
> @@ -422,6 +426,10 @@ const struct link_mode_info link_mode_params[] = {
>  	__DEFINE_LINK_MODE_PARAMS(800000, DR4_2, Full),
>  	__DEFINE_LINK_MODE_PARAMS(800000, SR4, Full),
>  	__DEFINE_LINK_MODE_PARAMS(800000, VR4, Full),
> +	__DEFINE_LINK_MODE_PARAMS(1600000, CR8, Full),
> +	__DEFINE_LINK_MODE_PARAMS(1600000, KR8, Full),
> +	__DEFINE_LINK_MODE_PARAMS(1600000, DR8, Full),
> +	__DEFINE_LINK_MODE_PARAMS(1600000, DR8_2, Full),
>  };
>  static_assert(ARRAY_SIZE(link_mode_params) == __ETHTOOL_LINK_MODE_MASK_NBITS);
>  EXPORT_SYMBOL_GPL(link_mode_params);