Re: [dpdk-dev] [PATCH] net/ixgbe: 10GBASE-T SFP+ copper support

[Ido Goshen <Ido@cgstowernetworks.com>]

> -----Original Message-----
> From: Ananyev, Konstantin <konstantin.ananyev@intel.com>
> Sent: Thursday, May 2, 2019 2:41 AM
> To: Ido Goshen <Ido@cgstowernetworks.com>; Lu, Wenzhuo
> <wenzhuo.lu@intel.com>
> Cc: dev@dpdk.org
> Subject: RE: [PATCH] net/ixgbe: 10GBASE-T SFP+ copper support
> 
> 
> 
> > -----Original Message-----
> > From: Ido Goshen [mailto:Ido@cgstowernetworks.com]
> > Sent: Sunday, April 28, 2019 7:54 AM
> > To: Ananyev, Konstantin <konstantin.ananyev@intel.com>; Lu, Wenzhuo
> > <wenzhuo.lu@intel.com>
> > Cc: dev@dpdk.org
> > Subject: RE: [PATCH] net/ixgbe: 10GBASE-T SFP+ copper support
> >
> >
> >
> > > -----Original Message-----
> > > From: Ananyev, Konstantin <konstantin.ananyev@intel.com>
> > > Sent: Friday, April 26, 2019 3:13 PM
> > > To: Ido Goshen <Ido@cgstowernetworks.com>; Lu, Wenzhuo
> > > <wenzhuo.lu@intel.com>
> > > Cc: dev@dpdk.org
> > > Subject: RE: [PATCH] net/ixgbe: 10GBASE-T SFP+ copper support
> > >
> > >
> > >
> > > > > > From: Ido Goshen <ido@cgstowernetworks.com>
> > > > > >
> > > > > > 10BASE-T SFP+ copper transceivers become cheaper and popular
> > > > > > So far those were blocked by ixgbe as “unsupported”.
> > > > > > e.g.
> > > > > > 	eth_ixgbe_dev_init(): Unsupported SFP+ Module
> > > > > > 	eth_ixgbe_dev_init(): Hardware Initialization Failure: -19
> > > > > > 	EAL: Requested device 0000:0a:00.0 cannot be used
> > > > > >
> > > > > > This patch expands the usage of allow_unsupported_sfp to be
> > > > > > more general and makes ixgbe more tolerant to unknown SFPs
> > > > >
> > > > >
> > > > > I don't think it is a good idea to change the base code to
> > > > > blindly allow unknown SFPs.
> > > > > Again in eth_ixgbe_dev_init() we do set
> > > > > hw->allow_unsupported_sfp = 1;
> > > > > so the function below will return success anyway,
> > > >
> > > > what's the reason to not allow unknown SFPs?
> > > > as is they are explicitly blocked and not working anyway, why not
> > > > give
> > > them a chance?
> > >
> > > From my perspective the question should be opposite: why to allow it?
> > > ixgbe base code is developed and maintained by Intel ND team for
> > > several platforms.
> > > It should be some good reason to change it inside DPDK project only.
> > > As I said,  in eth_ixgbe_dev_init() we already set
> > > hw->allow_unsupported_sfp = 1, so unknown spf should be allowed by
> DPDK ixgbe PMD.
> > > So what exact problem you are trying to solve here?
> > > Konstantin
> >
> > The problem is that 10GBASE-T copper transceivers are not working just
> > because they are unknown
> > http://www.eoptolink.com/products/copper-10g-sfp
> >
> > The hw->allow_unsupported_sfp is used too late in
> > https://git.dpdk.org/next/dpdk-next-net-intel/tree/drivers/net/ixgbe/b
> > ase/ixgbe_phy.c#n1530 And if we've already got out earlier in
> > https://git.dpdk.org/next/dpdk-next-net-intel/tree/drivers/net/ixgbe/b
> > ase/ixgbe_phy.c#n1507
> 
> As I can read the code that check is for 1G SFPs.
> So if you getting out here, then comp_codes_10g == 0 here, and it means
> that given SFP is not recognized as 10G one.
> I wonder why that happens?
> 
> As I can see comp_codes_10g should be initialized at line 1314:
> status = hw->phy.ops.read_i2c_eeprom(hw,
>                                                      IXGBE_SFF_10GBE_COMP_CODES,
>                                                      &comp_codes_10g);
> 

The samples I have (from 2 vendors) read 0 from the eeprom IXGBE_SFF_10GBE_COMP_CODES offset

SFF-8472 spec [https://members.snia.org/document/dl/25916] doesn't define a code value for 10GBASE-T 
	TABLE 5-3 TRANSCEIVER COMPLIANCE CODES	
	10G Ethernet Compliance Codes
	3 	7 	10G Base-ER 	 
	3 	6 	10G Base-LRM 
	3 	5 	10G Base-LR 
	3 	4 	10G Base-SR 
	Infiniband Compliance Codes
	3 	3 	1X SX
	3 	2 	1X LX
	3 	1 	1X Copper Active
	3 	0 	1X Copper Active
Seems they are right not to set any code from above, no?
 
Do you know any 10GBASE-T SFPs that does work? 
Any idea what does it return for this field?

> > The device cannot be used
> > The patch tries to make the hw->allow_unsupported_sfp more general and
> > in case it is set (always in dpdk) change any return status of
> > IXGBE_ERR_SFP_NOT_SUPPORTED to IXGBE_SUCCESS with
> ixgbe_phy_unknown
> >
> > Other suggestions how to make 10GBASE-T copper work?
> >
> > >
> > > >
> > > > More inputs
> > > > 1. i40e already does support it (I didn't go deep into it but it
> > > > just seems less strict on hw_init) 2. even with ixgbe it can work,
> > > > because
> > > unsupported is only checked by ixgbe_init_hw
> > > >      so if the SFP is inserted after the app has started it does work
> > > >      kind of inconsistent
> > > >
> > > > >
> > > > > >
> > > > > > Signed-off-by: Ido Goshen <ido@cgstowernetworks.com>
> > > > > > ---
> > > > > >  drivers/net/ixgbe/base/ixgbe_phy.c  | 22
> > > > > > +++++++++++----------- drivers/net/ixgbe/base/ixgbe_x550.c |
> > > > > > 3 +++
> > > > > >  2 files changed, 14 insertions(+), 11 deletions(-)
> > > > > >
> > > > > > diff --git a/drivers/net/ixgbe/base/ixgbe_phy.c
> > > > > > b/drivers/net/ixgbe/base/ixgbe_phy.c
> > > > > > index dd118f9..ff96afc 100644
> > > > > > --- a/drivers/net/ixgbe/base/ixgbe_phy.c
> > > > > > +++ b/drivers/net/ixgbe/base/ixgbe_phy.c
> > > > > > @@ -1527,18 +1527,9 @@ s32
> > > > > > ixgbe_identify_sfp_module_generic(struct
> > > > > ixgbe_hw *hw)
> > > > > >  			if (hw->phy.type == ixgbe_phy_sfp_intel) {
> > > > > >  				status = IXGBE_SUCCESS;
> > > > > >  			} else {
> > > > > > -				if (hw->allow_unsupported_sfp ==
> true) {
> > > > > > -					EWARN(hw,
> > > > > > -						"WARNING: Intel (R)
> > > > > Network Connections are quality tested using Intel (R) Ethernet
> > > > > > Optics. "
> > > > > > -						"Using untested
> modules is
> > > > > not supported and may cause unstable operation or damage
> > > > > > to the module or the adapter. "
> > > > > > -						"Intel Corporation is
> not
> > > > > responsible for any harm caused by using untested modules.\n");
> > > > > > -					status = IXGBE_SUCCESS;
> > > > > > -				} else {
> > > > > > -					DEBUGOUT("SFP+ module
> not
> > > > > supported\n");
> > > > > > -					hw->phy.type =
> > > > > > +				hw->phy.type =
> > > > > >
> 	ixgbe_phy_sfp_unsupported;
> > > > > > -					status =
> > > > > IXGBE_ERR_SFP_NOT_SUPPORTED;
> > > > > > -				}
> > > > > > +				status =
> IXGBE_ERR_SFP_NOT_SUPPORTED;
> > > > > >  			}
> > > > > >  		} else {
> > > > > >  			status = IXGBE_SUCCESS;
> > > > > > @@ -1546,6 +1537,15 @@ s32
> > > > > > ixgbe_identify_sfp_module_generic(struct
> > > > > ixgbe_hw *hw)
> > > > > >  	}
> > > > > >
> > > > > >  out:
> > > > > > +	if (status == IXGBE_ERR_SFP_NOT_SUPPORTED &&
> > > > > > +			hw->allow_unsupported_sfp) {
> > > > > > +		PMD_INIT_LOG(WARNING,
> > > > > > +				"WARNING: Intel (R) Network
> Connections
> > > > > are quality tested using Intel (R) Ethernet Optics. "
> > > > > > +				"Using untested modules is not
> supported
> > > > > and may cause unstable
> > > > > > +operation or damage to the module or
> > > > > > the adapter. "
> > > > > > +				"Intel Corporation is not responsible
> for any
> > > > > harm caused by using untested modules.\n");
> > > > > > +		hw->phy.type = ixgbe_phy_unknown;
> > > > > > +		status = IXGBE_SUCCESS;
> > > > > > +	}
> > > > > >  	return status;
> > > > > >
> > > > > >  err_read_i2c_eeprom:
> > > > > > diff --git a/drivers/net/ixgbe/base/ixgbe_x550.c
> > > > > > b/drivers/net/ixgbe/base/ixgbe_x550.c
> > > > > > index a920a14..212d9a0 100644
> > > > > > --- a/drivers/net/ixgbe/base/ixgbe_x550.c
> > > > > > +++ b/drivers/net/ixgbe/base/ixgbe_x550.c
> > > > > > @@ -1539,6 +1539,9 @@ STATIC s32
> > > > > ixgbe_supported_sfp_modules_X550em(struct ixgbe_hw *hw, bool
> > > > > *linear)
> > > > > >  		*linear = false;
> > > > > >  		break;
> > > > > >  	case ixgbe_sfp_type_unknown:
> > > > > > +		if (hw->allow_unsupported_sfp)
> > > > > > +			return IXGBE_SUCCESS;
> > > > > > +		/* fall through */
> > > > > >  	case ixgbe_sfp_type_1g_cu_core0:
> > > > > >  	case ixgbe_sfp_type_1g_cu_core1:
> > > > > >  	default:
> > > > > > --
> > > > > > 1.9.1