[PATCH v2 net-next] ethtool: link 10000baseCR to SFF-8431, Appendix-E SFP+ DA

[PATCH v2 net-next] ethtool: link 10000baseCR to SFF-8431, Appendix-E SFP+ DA

[Siddaraju DH]

Add comment to clarify the physical media 10000baseCR follows.

10000baseCR does not correspond to any IEEE 802.3 *base-CR PMD.
It has no autonegotiation, no link training, and no mandatory FEC.
The industry standard for this media type is SFF-8431 Appendix-E
Direct Attach cable, also known as 10G_SFI_DA.

Link: https://lore.kernel.org/r/SN7PR11MB69003D33489DB1D6B17EF72A9AF52@SN7PR11MB6900.namprd11.prod.outlook.com

Signed-off-by: Siddaraju DH <siddaraju.dh@intel.com>
---
 include/uapi/linux/ethtool.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index a2091d4e00f3..986d70caec33 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -2013,7 +2013,13 @@ enum ethtool_link_mode_bit_indices {
 	ETHTOOL_LINK_MODE_100000baseLR4_ER4_Full_BIT	= 39,
 	ETHTOOL_LINK_MODE_50000baseSR2_Full_BIT		= 40,
 	ETHTOOL_LINK_MODE_1000baseX_Full_BIT	= 41,
+
+	/* Despite the "baseCR" in 10000baseCR, this is not an IEEE 802.3 baseCR
+	 * It represents SFF-8431 Appendix-E SFP+ Direct Attach (10G-SFI-DA).
+	 * The name is kept as-is for uAPI backward compatibility.
+	 */
 	ETHTOOL_LINK_MODE_10000baseCR_Full_BIT	= 42,
+
 	ETHTOOL_LINK_MODE_10000baseSR_Full_BIT	= 43,
 	ETHTOOL_LINK_MODE_10000baseLR_Full_BIT	= 44,
 	ETHTOOL_LINK_MODE_10000baseLRM_Full_BIT	= 45,
-- 
2.25.1

Re: [PATCH v2 net-next] ethtool: link 10000baseCR to SFF-8431, Appendix-E SFP+ DA

[Maxime Chevallier]

Hi

On 7/3/26 12:05, Siddaraju DH wrote:
> Add comment to clarify the physical media 10000baseCR follows.
> 
> 10000baseCR does not correspond to any IEEE 802.3 *base-CR PMD.
> It has no autonegotiation, no link training, and no mandatory FEC.
> The industry standard for this media type is SFF-8431 Appendix-E
> Direct Attach cable, also known as 10G_SFI_DA.
> 
> Link: https://lore.kernel.org/r/SN7PR11MB69003D33489DB1D6B17EF72A9AF52@SN7PR11MB6900.namprd11.prod.outlook.com
> 
> Signed-off-by: Siddaraju DH <siddaraju.dh@intel.com>

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

Maxime

Re: [PATCH v2 net-next] ethtool: link 10000baseCR to SFF-8431, Appendix-E SFP+ DA

[Jakub Kicinski]

On Fri,  3 Jul 2026 15:35:37 +0530 Siddaraju DH wrote:
> Add comment to clarify the physical media 10000baseCR follows.
> 
> 10000baseCR does not correspond to any IEEE 802.3 *base-CR PMD.
> It has no autonegotiation, no link training, and no mandatory FEC.
> The industry standard for this media type is SFF-8431 Appendix-E
> Direct Attach cable, also known as 10G_SFI_DA.

This patch fell out of patchwork, due to vacations and conferences.
Please repost.

RE: [PATCH v2 net-next] ethtool: link 10000baseCR to SFF-8431, Appendix-E SFP+ DA

[D H, Siddaraju]

Done, thank you Kuba 😊.
Link: https://lore.kernel.org/netdev/20260721150638.3084698-1-siddaraju.dh@intel.com/

- Thank you,
Siddaraju D H

-----Original Message-----
From: Jakub Kicinski <kuba@kernel.org> 
Sent: Tuesday, July 21, 2026 5:14 AM
To: D H, Siddaraju <siddaraju.dh@intel.com>
Cc: Michal Kubecek <mkubecek@suse.cz>; Andrew Lunn <andrew@lunn.ch>; Maxime Chevallier <maxime.chevallier@bootlin.com>; netdev@vger.kernel.org; Das, Shubham <shubham.das@intel.com>; Chintalapalle, Balaji <balaji.chintalapalle@intel.com>; Srinivasan, Vijay <vijay.srinivasan@intel.com>; Lindberg, Magnus <magnus.k.lindberg@ericsson.com>; Niklas Damberg <niklas.damberg@ericsson.com>; Wirandi, Jonas <jonas.wirandi@ericsson.com>; Siddaraju DH <siddarajudh@gmail.com>
Subject: Re: [PATCH v2 net-next] ethtool: link 10000baseCR to SFF-8431, Appendix-E SFP+ DA

On Fri,  3 Jul 2026 15:35:37 +0530 Siddaraju DH wrote:
> Add comment to clarify the physical media 10000baseCR follows.
> 
> 10000baseCR does not correspond to any IEEE 802.3 *base-CR PMD.
> It has no autonegotiation, no link training, and no mandatory FEC.
> The industry standard for this media type is SFF-8431 Appendix-E
> Direct Attach cable, also known as 10G_SFI_DA.

This patch fell out of patchwork, due to vacations and conferences.
Please repost.