* [PATCH net-next] net: pcs: xpcs: Add 2500BASE-X case in get state for XPCS drivers @ 2023-09-25 7:51 Raju Lakkaraju 2023-09-26 11:39 ` Serge Semin 0 siblings, 1 reply; 8+ messages in thread From: Raju Lakkaraju @ 2023-09-25 7:51 UTC (permalink / raw) To: netdev; +Cc: davem, Jose.Abreu, linux, hkallweit1, UNGLinuxDriver Add DW_2500BASEX case in xpcs_get_state( ) to update speed, duplex and pause Update the port mode and autonegotiation Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microchip.com> --- drivers/net/pcs/pcs-xpcs.c | 31 +++++++++++++++++++++++++++++++ drivers/net/pcs/pcs-xpcs.h | 4 ++++ 2 files changed, 35 insertions(+) diff --git a/drivers/net/pcs/pcs-xpcs.c b/drivers/net/pcs/pcs-xpcs.c index 4dbc21f604f2..4f89dcedf0fc 100644 --- a/drivers/net/pcs/pcs-xpcs.c +++ b/drivers/net/pcs/pcs-xpcs.c @@ -1090,6 +1090,30 @@ static int xpcs_get_state_c37_1000basex(struct dw_xpcs *xpcs, return 0; } +static int xpcs_get_state_2500basex(struct dw_xpcs *xpcs, + struct phylink_link_state *state) +{ + int sts, lpa; + + sts = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_MMD_STS); + lpa = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_MMD_LP_BABL); + if (sts < 0 || lpa < 0) { + state->link = false; + return sts; + } + + state->link = !!(sts & DW_VR_MII_MMD_STS_LINK_STS); + state->an_complete = !!(sts & DW_VR_MII_MMD_STS_AN_CMPL); + if (!state->link) + return 0; + + state->speed = SPEED_2500; + state->pause |= MLO_PAUSE_TX | MLO_PAUSE_RX; + state->duplex = DUPLEX_FULL; + + return 0; +} + static void xpcs_get_state(struct phylink_pcs *pcs, struct phylink_link_state *state) { @@ -1127,6 +1151,13 @@ static void xpcs_get_state(struct phylink_pcs *pcs, ERR_PTR(ret)); } break; + case DW_2500BASEX: + ret = xpcs_get_state_2500basex(xpcs, state); + if (ret) { + pr_err("xpcs_get_state_2500basex returned %pe\n", + ERR_PTR(ret)); + } + break; default: return; } diff --git a/drivers/net/pcs/pcs-xpcs.h b/drivers/net/pcs/pcs-xpcs.h index 39a90417e535..92c838f4b251 100644 --- a/drivers/net/pcs/pcs-xpcs.h +++ b/drivers/net/pcs/pcs-xpcs.h @@ -55,6 +55,10 @@ /* Clause 37 Defines */ /* VR MII MMD registers offsets */ #define DW_VR_MII_MMD_CTRL 0x0000 +#define DW_VR_MII_MMD_STS 0x0001 +#define DW_VR_MII_MMD_STS_LINK_STS BIT(2) +#define DW_VR_MII_MMD_STS_AN_CMPL BIT(5) +#define DW_VR_MII_MMD_LP_BABL 0x0005 #define DW_VR_MII_DIG_CTRL1 0x8000 #define DW_VR_MII_AN_CTRL 0x8001 #define DW_VR_MII_AN_INTR_STS 0x8002 -- 2.34.1 ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH net-next] net: pcs: xpcs: Add 2500BASE-X case in get state for XPCS drivers 2023-09-25 7:51 [PATCH net-next] net: pcs: xpcs: Add 2500BASE-X case in get state for XPCS drivers Raju Lakkaraju @ 2023-09-26 11:39 ` Serge Semin 2023-09-26 11:45 ` Russell King (Oracle) 0 siblings, 1 reply; 8+ messages in thread From: Serge Semin @ 2023-09-26 11:39 UTC (permalink / raw) To: Raju Lakkaraju Cc: netdev, davem, Jose.Abreu, linux, hkallweit1, UNGLinuxDriver Hi Raju On Mon, Sep 25, 2023 at 01:21:42PM +0530, Raju Lakkaraju wrote: > Add DW_2500BASEX case in xpcs_get_state( ) to update speed, duplex and pause > Update the port mode and autonegotiation > > Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microchip.com> > --- > drivers/net/pcs/pcs-xpcs.c | 31 +++++++++++++++++++++++++++++++ > drivers/net/pcs/pcs-xpcs.h | 4 ++++ > 2 files changed, 35 insertions(+) > > diff --git a/drivers/net/pcs/pcs-xpcs.c b/drivers/net/pcs/pcs-xpcs.c > index 4dbc21f604f2..4f89dcedf0fc 100644 > --- a/drivers/net/pcs/pcs-xpcs.c > +++ b/drivers/net/pcs/pcs-xpcs.c > @@ -1090,6 +1090,30 @@ static int xpcs_get_state_c37_1000basex(struct dw_xpcs *xpcs, > return 0; > } > > +static int xpcs_get_state_2500basex(struct dw_xpcs *xpcs, > + struct phylink_link_state *state) > +{ > + int sts, lpa; > + > + sts = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_MMD_STS); > + lpa = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_MMD_LP_BABL); > + if (sts < 0 || lpa < 0) { > + state->link = false; > + return sts; > + } The HW manual says: "The host uses this page to know the link partner's ability when the base page is received through Clause 37 auto-negotiation." Seeing xpcs_config_2500basex() disables auto-negotiation and lpa value is unused anyway why do you even need to read the LP_BABL register? > + > + state->link = !!(sts & DW_VR_MII_MMD_STS_LINK_STS); > + state->an_complete = !!(sts & DW_VR_MII_MMD_STS_AN_CMPL); Similarly AN is disabled in the xpcs_config_2500basex() method. Why do you need the parsing above? It isn't supposed to indicate any useful value since AN is disabled. -Serge(y) > + if (!state->link) > + return 0; > + > + state->speed = SPEED_2500; > + state->pause |= MLO_PAUSE_TX | MLO_PAUSE_RX; > + state->duplex = DUPLEX_FULL; > + > + return 0; > +} > + > static void xpcs_get_state(struct phylink_pcs *pcs, > struct phylink_link_state *state) > { > @@ -1127,6 +1151,13 @@ static void xpcs_get_state(struct phylink_pcs *pcs, > ERR_PTR(ret)); > } > break; > + case DW_2500BASEX: > + ret = xpcs_get_state_2500basex(xpcs, state); > + if (ret) { > + pr_err("xpcs_get_state_2500basex returned %pe\n", > + ERR_PTR(ret)); > + } > + break; > default: > return; > } > diff --git a/drivers/net/pcs/pcs-xpcs.h b/drivers/net/pcs/pcs-xpcs.h > index 39a90417e535..92c838f4b251 100644 > --- a/drivers/net/pcs/pcs-xpcs.h > +++ b/drivers/net/pcs/pcs-xpcs.h > @@ -55,6 +55,10 @@ > /* Clause 37 Defines */ > /* VR MII MMD registers offsets */ > #define DW_VR_MII_MMD_CTRL 0x0000 > +#define DW_VR_MII_MMD_STS 0x0001 > +#define DW_VR_MII_MMD_STS_LINK_STS BIT(2) > +#define DW_VR_MII_MMD_STS_AN_CMPL BIT(5) > +#define DW_VR_MII_MMD_LP_BABL 0x0005 > #define DW_VR_MII_DIG_CTRL1 0x8000 > #define DW_VR_MII_AN_CTRL 0x8001 > #define DW_VR_MII_AN_INTR_STS 0x8002 > -- > 2.34.1 > > ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH net-next] net: pcs: xpcs: Add 2500BASE-X case in get state for XPCS drivers 2023-09-26 11:39 ` Serge Semin @ 2023-09-26 11:45 ` Russell King (Oracle) 2023-09-26 12:09 ` Serge Semin 0 siblings, 1 reply; 8+ messages in thread From: Russell King (Oracle) @ 2023-09-26 11:45 UTC (permalink / raw) To: Serge Semin Cc: Raju Lakkaraju, netdev, davem, Jose.Abreu, hkallweit1, UNGLinuxDriver On Tue, Sep 26, 2023 at 02:39:21PM +0300, Serge Semin wrote: > Hi Raju > > On Mon, Sep 25, 2023 at 01:21:42PM +0530, Raju Lakkaraju wrote: > > Add DW_2500BASEX case in xpcs_get_state( ) to update speed, duplex and pause > > Update the port mode and autonegotiation > > > > Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microchip.com> > > --- > > drivers/net/pcs/pcs-xpcs.c | 31 +++++++++++++++++++++++++++++++ > > drivers/net/pcs/pcs-xpcs.h | 4 ++++ > > 2 files changed, 35 insertions(+) > > > > diff --git a/drivers/net/pcs/pcs-xpcs.c b/drivers/net/pcs/pcs-xpcs.c > > index 4dbc21f604f2..4f89dcedf0fc 100644 > > --- a/drivers/net/pcs/pcs-xpcs.c > > +++ b/drivers/net/pcs/pcs-xpcs.c > > @@ -1090,6 +1090,30 @@ static int xpcs_get_state_c37_1000basex(struct dw_xpcs *xpcs, > > return 0; > > } > > > > +static int xpcs_get_state_2500basex(struct dw_xpcs *xpcs, > > + struct phylink_link_state *state) > > +{ > > + int sts, lpa; > > + > > + sts = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_MMD_STS); > > > + lpa = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_MMD_LP_BABL); > > + if (sts < 0 || lpa < 0) { > > + state->link = false; > > + return sts; > > + } > > The HW manual says: "The host uses this page to know the link > partner's ability when the base page is received through Clause 37 > auto-negotiation." Seeing xpcs_config_2500basex() disables > auto-negotiation and lpa value is unused anyway why do you even need > to read the LP_BABL register? Since you have access to the hardware manual, what does it say about clause 37 auto-negotiation when operating in 2500base-X mode? Thanks. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last! ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH net-next] net: pcs: xpcs: Add 2500BASE-X case in get state for XPCS drivers 2023-09-26 11:45 ` Russell King (Oracle) @ 2023-09-26 12:09 ` Serge Semin 2023-09-26 14:46 ` Russell King (Oracle) 0 siblings, 1 reply; 8+ messages in thread From: Serge Semin @ 2023-09-26 12:09 UTC (permalink / raw) To: Russell King (Oracle) Cc: Raju Lakkaraju, netdev, davem, Jose.Abreu, hkallweit1, UNGLinuxDriver Hi Russell On Tue, Sep 26, 2023 at 12:45:47PM +0100, Russell King (Oracle) wrote: > On Tue, Sep 26, 2023 at 02:39:21PM +0300, Serge Semin wrote: > > Hi Raju > > > > On Mon, Sep 25, 2023 at 01:21:42PM +0530, Raju Lakkaraju wrote: > > > Add DW_2500BASEX case in xpcs_get_state( ) to update speed, duplex and pause > > > Update the port mode and autonegotiation > > > > > > Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microchip.com> > > > --- > > > drivers/net/pcs/pcs-xpcs.c | 31 +++++++++++++++++++++++++++++++ > > > drivers/net/pcs/pcs-xpcs.h | 4 ++++ > > > 2 files changed, 35 insertions(+) > > > > > > diff --git a/drivers/net/pcs/pcs-xpcs.c b/drivers/net/pcs/pcs-xpcs.c > > > index 4dbc21f604f2..4f89dcedf0fc 100644 > > > --- a/drivers/net/pcs/pcs-xpcs.c > > > +++ b/drivers/net/pcs/pcs-xpcs.c > > > @@ -1090,6 +1090,30 @@ static int xpcs_get_state_c37_1000basex(struct dw_xpcs *xpcs, > > > return 0; > > > } > > > > > > +static int xpcs_get_state_2500basex(struct dw_xpcs *xpcs, > > > + struct phylink_link_state *state) > > > +{ > > > + int sts, lpa; > > > + > > > + sts = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_MMD_STS); > > > > > + lpa = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_MMD_LP_BABL); > > > + if (sts < 0 || lpa < 0) { > > > + state->link = false; > > > + return sts; > > > + } > > > > The HW manual says: "The host uses this page to know the link > > partner's ability when the base page is received through Clause 37 > > auto-negotiation." Seeing xpcs_config_2500basex() disables > > auto-negotiation and lpa value is unused anyway why do you even need > > to read the LP_BABL register? > > Since you have access to the hardware manual, what does it say about > clause 37 auto-negotiation when operating in 2500base-X mode? Here are the parts which mention 37 & SGMII AN in the 2.5G context: 1. "Clause 37 (& SGMII) auto-negotiation is supported in 2.5G mode if the link partner is also operating in the equivalent 2.5G mode." 2. "During the Clause 37/SGMII as the auto-negotiation link timer operates with a faster clock in the 2.5G mode, the timeout duration reduces by a factor of 2.5. To restore the standard specified timeout period, the respective registers must be re-programmed." I guess the entire 2.5G-thing understanding could be generalized by the next sentence from the HW manual: "The 2.5G mode of operation is functionally the same as 1000BASE-X/KX mode, except that the clock-rate is 2.5 times the original rate. In this mode, the Serdes/PHY operates at a serial baud-rate of 3.125 Gbps and DWC_xpcs data-path and the GMII interface to MAC operates at 312.5 MHz (instead of 125 MHz)." Thus here is another info regarding AN in that context: 3. "The DWC_xpcs operates either in 10/100/1000Mbps rate or 25/250/2500Mbps rates respectively with SGMII auto-negotiation. The DWC_xpcs cannot support switching or negotiation between 1G and 2.5G rates using auto-negotiation." -Serge(y) > > Thanks. > > -- > RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ > FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last! ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH net-next] net: pcs: xpcs: Add 2500BASE-X case in get state for XPCS drivers 2023-09-26 12:09 ` Serge Semin @ 2023-09-26 14:46 ` Russell King (Oracle) 2023-09-26 15:27 ` Serge Semin 0 siblings, 1 reply; 8+ messages in thread From: Russell King (Oracle) @ 2023-09-26 14:46 UTC (permalink / raw) To: Serge Semin Cc: Raju Lakkaraju, netdev, davem, Jose.Abreu, hkallweit1, UNGLinuxDriver On Tue, Sep 26, 2023 at 03:09:47PM +0300, Serge Semin wrote: > Hi Russell > > On Tue, Sep 26, 2023 at 12:45:47PM +0100, Russell King (Oracle) wrote: > > On Tue, Sep 26, 2023 at 02:39:21PM +0300, Serge Semin wrote: > > > Hi Raju > > > > > > On Mon, Sep 25, 2023 at 01:21:42PM +0530, Raju Lakkaraju wrote: > > > > Add DW_2500BASEX case in xpcs_get_state( ) to update speed, duplex and pause > > > > Update the port mode and autonegotiation > > > > > > > > Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microchip.com> > > > > --- > > > > drivers/net/pcs/pcs-xpcs.c | 31 +++++++++++++++++++++++++++++++ > > > > drivers/net/pcs/pcs-xpcs.h | 4 ++++ > > > > 2 files changed, 35 insertions(+) > > > > > > > > diff --git a/drivers/net/pcs/pcs-xpcs.c b/drivers/net/pcs/pcs-xpcs.c > > > > index 4dbc21f604f2..4f89dcedf0fc 100644 > > > > --- a/drivers/net/pcs/pcs-xpcs.c > > > > +++ b/drivers/net/pcs/pcs-xpcs.c > > > > @@ -1090,6 +1090,30 @@ static int xpcs_get_state_c37_1000basex(struct dw_xpcs *xpcs, > > > > return 0; > > > > } > > > > > > > > +static int xpcs_get_state_2500basex(struct dw_xpcs *xpcs, > > > > + struct phylink_link_state *state) > > > > +{ > > > > + int sts, lpa; > > > > + > > > > + sts = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_MMD_STS); > > > > > > > + lpa = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_MMD_LP_BABL); > > > > + if (sts < 0 || lpa < 0) { > > > > + state->link = false; > > > > + return sts; > > > > + } > > > > > > The HW manual says: "The host uses this page to know the link > > > partner's ability when the base page is received through Clause 37 > > > auto-negotiation." Seeing xpcs_config_2500basex() disables > > > auto-negotiation and lpa value is unused anyway why do you even need > > > to read the LP_BABL register? > > > > > Since you have access to the hardware manual, what does it say about > > clause 37 auto-negotiation when operating in 2500base-X mode? > > Here are the parts which mention 37 & SGMII AN in the 2.5G context: > > 1. "Clause 37 (& SGMII) auto-negotiation is supported in 2.5G mode if > the link partner is also operating in the equivalent 2.5G mode." > > 2. "During the Clause 37/SGMII as the auto-negotiation link timer > operates with a faster clock in the 2.5G mode, the timeout duration > reduces by a factor of 2.5. To restore the standard specified timeout > period, the respective registers must be re-programmed." > > I guess the entire 2.5G-thing understanding could be generalized by > the next sentence from the HW manual: "The 2.5G mode of operation is > functionally the same as 1000BASE-X/KX mode, except that the > clock-rate is 2.5 times the original rate. In this mode, the > Serdes/PHY operates at a serial baud-rate of 3.125 Gbps and DWC_xpcs > data-path and the GMII interface to MAC operates at 312.5 MHz (instead > of 125 MHz)." Thus here is another info regarding AN in that context: > > 3. "The DWC_xpcs operates either in 10/100/1000Mbps rate or > 25/250/2500Mbps rates respectively with SGMII auto-negotiation. The > DWC_xpcs cannot support switching or negotiation between 1G and 2.5G > rates using auto-negotiation." Thanks for the clarification. So this hardware, just like Marvell hardware, operates 2500BASE-X merely by up-clocking, and all the features that were available at 1000BASE-X are also available at 2500BASE-X, including the in-band signalling. Therefore, I think rather than disabling AN outright, the PHYLINK_PCS_NEG_* mode passed in should be checked to determine whether inband should be used or not. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last! ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH net-next] net: pcs: xpcs: Add 2500BASE-X case in get state for XPCS drivers 2023-09-26 14:46 ` Russell King (Oracle) @ 2023-09-26 15:27 ` Serge Semin 2023-09-26 15:47 ` Russell King (Oracle) 0 siblings, 1 reply; 8+ messages in thread From: Serge Semin @ 2023-09-26 15:27 UTC (permalink / raw) To: Russell King (Oracle) Cc: Raju Lakkaraju, netdev, davem, Jose.Abreu, hkallweit1, UNGLinuxDriver On Tue, Sep 26, 2023 at 03:46:23PM +0100, Russell King (Oracle) wrote: > On Tue, Sep 26, 2023 at 03:09:47PM +0300, Serge Semin wrote: > > Hi Russell > > > > On Tue, Sep 26, 2023 at 12:45:47PM +0100, Russell King (Oracle) wrote: > > > On Tue, Sep 26, 2023 at 02:39:21PM +0300, Serge Semin wrote: > > > > Hi Raju > > > > > > > > On Mon, Sep 25, 2023 at 01:21:42PM +0530, Raju Lakkaraju wrote: > > > > > Add DW_2500BASEX case in xpcs_get_state( ) to update speed, duplex and pause > > > > > Update the port mode and autonegotiation > > > > > > > > > > Signed-off-by: Raju Lakkaraju <Raju.Lakkaraju@microchip.com> > > > > > --- > > > > > drivers/net/pcs/pcs-xpcs.c | 31 +++++++++++++++++++++++++++++++ > > > > > drivers/net/pcs/pcs-xpcs.h | 4 ++++ > > > > > 2 files changed, 35 insertions(+) > > > > > > > > > > diff --git a/drivers/net/pcs/pcs-xpcs.c b/drivers/net/pcs/pcs-xpcs.c > > > > > index 4dbc21f604f2..4f89dcedf0fc 100644 > > > > > --- a/drivers/net/pcs/pcs-xpcs.c > > > > > +++ b/drivers/net/pcs/pcs-xpcs.c > > > > > @@ -1090,6 +1090,30 @@ static int xpcs_get_state_c37_1000basex(struct dw_xpcs *xpcs, > > > > > return 0; > > > > > } > > > > > > > > > > +static int xpcs_get_state_2500basex(struct dw_xpcs *xpcs, > > > > > + struct phylink_link_state *state) > > > > > +{ > > > > > + int sts, lpa; > > > > > + > > > > > + sts = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_MMD_STS); > > > > > > > > > + lpa = xpcs_read(xpcs, MDIO_MMD_VEND2, DW_VR_MII_MMD_LP_BABL); > > > > > + if (sts < 0 || lpa < 0) { > > > > > + state->link = false; > > > > > + return sts; > > > > > + } > > > > > > > > The HW manual says: "The host uses this page to know the link > > > > partner's ability when the base page is received through Clause 37 > > > > auto-negotiation." Seeing xpcs_config_2500basex() disables > > > > auto-negotiation and lpa value is unused anyway why do you even need > > > > to read the LP_BABL register? > > > > > > > > Since you have access to the hardware manual, what does it say about > > > clause 37 auto-negotiation when operating in 2500base-X mode? > > > > Here are the parts which mention 37 & SGMII AN in the 2.5G context: > > > > 1. "Clause 37 (& SGMII) auto-negotiation is supported in 2.5G mode if > > the link partner is also operating in the equivalent 2.5G mode." > > > > 2. "During the Clause 37/SGMII as the auto-negotiation link timer > > operates with a faster clock in the 2.5G mode, the timeout duration > > reduces by a factor of 2.5. To restore the standard specified timeout > > period, the respective registers must be re-programmed." > > > > I guess the entire 2.5G-thing understanding could be generalized by > > the next sentence from the HW manual: "The 2.5G mode of operation is > > functionally the same as 1000BASE-X/KX mode, except that the > > clock-rate is 2.5 times the original rate. In this mode, the > > Serdes/PHY operates at a serial baud-rate of 3.125 Gbps and DWC_xpcs > > data-path and the GMII interface to MAC operates at 312.5 MHz (instead > > of 125 MHz)." Thus here is another info regarding AN in that context: > > > > 3. "The DWC_xpcs operates either in 10/100/1000Mbps rate or > > 25/250/2500Mbps rates respectively with SGMII auto-negotiation. The > > DWC_xpcs cannot support switching or negotiation between 1G and 2.5G > > rates using auto-negotiation." > > Thanks for the clarification. > > So this hardware, just like Marvell hardware, operates 2500BASE-X merely > by up-clocking, and all the features that were available at 1000BASE-X > are also available at 2500BASE-X, including the in-band signalling. > > Therefore, I think rather than disabling AN outright, the > PHYLINK_PCS_NEG_* mode passed in should be checked to determine whether > inband should be used or not. Just an additional note which might be relevant in the context of the DW XPCS 1G/2.5G C37 AN. The C37 auto-negotiation feature will be unavailable for 1000BASE-X and thus for 2500BASE-X if the IP-core is synthesized with no support of one. It is determined by the CL37_AN IP-core synthesize parameter state: Enable SGMII Clause 37 | Description: Configures DWC_xpcs to support the Auto-Negotiation | Clause 37 auto-negotiation | | Dependencies: This option is available in the | following configurations: | - SUPPORT_1G = Enabled | - MAIN_MODE = Backplane Ethernet PCS and | BACKPLANE_ETH_CONFIG = KX_Only or KX4_KX | or KR_KX or KR_KX4_KX mode | | Default Value: Enabled for configurations with | MAIN_MODE = 1000BASEX-Only PCS and Disabled | for all other configurations | | HDL Parameter Name: CL37_AN So depending on the particular (vendor-specific) device configuration the C37 AN might still unavailable even though the device supports the 1000BASE-X and 2500BASE-X interfaces. -Serge(y) > > -- > RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ > FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last! ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH net-next] net: pcs: xpcs: Add 2500BASE-X case in get state for XPCS drivers 2023-09-26 15:27 ` Serge Semin @ 2023-09-26 15:47 ` Russell King (Oracle) 2023-09-26 19:40 ` Serge Semin 0 siblings, 1 reply; 8+ messages in thread From: Russell King (Oracle) @ 2023-09-26 15:47 UTC (permalink / raw) To: Serge Semin Cc: Raju Lakkaraju, netdev, davem, Jose.Abreu, hkallweit1, UNGLinuxDriver On Tue, Sep 26, 2023 at 06:27:45PM +0300, Serge Semin wrote: > On Tue, Sep 26, 2023 at 03:46:23PM +0100, Russell King (Oracle) wrote: > > On Tue, Sep 26, 2023 at 03:09:47PM +0300, Serge Semin wrote: > > > Hi Russell > > > > > > > Since you have access to the hardware manual, what does it say about > > > > clause 37 auto-negotiation when operating in 2500base-X mode? > > > > > > Here are the parts which mention 37 & SGMII AN in the 2.5G context: > > > > > > 1. "Clause 37 (& SGMII) auto-negotiation is supported in 2.5G mode if > > > the link partner is also operating in the equivalent 2.5G mode." > > > > > > 2. "During the Clause 37/SGMII as the auto-negotiation link timer > > > operates with a faster clock in the 2.5G mode, the timeout duration > > > reduces by a factor of 2.5. To restore the standard specified timeout > > > period, the respective registers must be re-programmed." > > > > > > I guess the entire 2.5G-thing understanding could be generalized by > > > the next sentence from the HW manual: "The 2.5G mode of operation is > > > functionally the same as 1000BASE-X/KX mode, except that the > > > clock-rate is 2.5 times the original rate. In this mode, the > > > Serdes/PHY operates at a serial baud-rate of 3.125 Gbps and DWC_xpcs > > > data-path and the GMII interface to MAC operates at 312.5 MHz (instead > > > of 125 MHz)." Thus here is another info regarding AN in that context: > > > > > > 3. "The DWC_xpcs operates either in 10/100/1000Mbps rate or > > > 25/250/2500Mbps rates respectively with SGMII auto-negotiation. The > > > DWC_xpcs cannot support switching or negotiation between 1G and 2.5G > > > rates using auto-negotiation." > > > > Thanks for the clarification. > > > > So this hardware, just like Marvell hardware, operates 2500BASE-X merely > > by up-clocking, and all the features that were available at 1000BASE-X > > are also available at 2500BASE-X, including the in-band signalling. > > > > Therefore, I think rather than disabling AN outright, the > > PHYLINK_PCS_NEG_* mode passed in should be checked to determine whether > > inband should be used or not. > > Just an additional note which might be relevant in the context of the > DW XPCS 1G/2.5G C37 AN. The C37 auto-negotiation feature will be > unavailable for 1000BASE-X and thus for 2500BASE-X if the IP-core is > synthesized with no support of one. It is determined by the CL37_AN > IP-core synthesize parameter state: > > Enable SGMII Clause 37 | Description: Configures DWC_xpcs to support the > Auto-Negotiation | Clause 37 auto-negotiation > | > | Dependencies: This option is available in the > | following configurations: > | - SUPPORT_1G = Enabled > | - MAIN_MODE = Backplane Ethernet PCS and > | BACKPLANE_ETH_CONFIG = KX_Only or KX4_KX > | or KR_KX or KR_KX4_KX mode > | > | Default Value: Enabled for configurations with > | MAIN_MODE = 1000BASEX-Only PCS and Disabled > | for all other configurations > | > | HDL Parameter Name: CL37_AN > > So depending on the particular (vendor-specific) device configuration > the C37 AN might still unavailable even though the device supports the > 1000BASE-X and 2500BASE-X interfaces. Thanks. I guess there's no way to read the CL37_AN setting from software? -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last! ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH net-next] net: pcs: xpcs: Add 2500BASE-X case in get state for XPCS drivers 2023-09-26 15:47 ` Russell King (Oracle) @ 2023-09-26 19:40 ` Serge Semin 0 siblings, 0 replies; 8+ messages in thread From: Serge Semin @ 2023-09-26 19:40 UTC (permalink / raw) To: Russell King (Oracle) Cc: Raju Lakkaraju, netdev, davem, Jose.Abreu, hkallweit1, UNGLinuxDriver On Tue, Sep 26, 2023 at 04:47:14PM +0100, Russell King (Oracle) wrote: > On Tue, Sep 26, 2023 at 06:27:45PM +0300, Serge Semin wrote: > > On Tue, Sep 26, 2023 at 03:46:23PM +0100, Russell King (Oracle) wrote: > > > On Tue, Sep 26, 2023 at 03:09:47PM +0300, Serge Semin wrote: > > > > Hi Russell > > > > > > > > > Since you have access to the hardware manual, what does it say about > > > > > clause 37 auto-negotiation when operating in 2500base-X mode? > > > > > > > > Here are the parts which mention 37 & SGMII AN in the 2.5G context: > > > > > > > > 1. "Clause 37 (& SGMII) auto-negotiation is supported in 2.5G mode if > > > > the link partner is also operating in the equivalent 2.5G mode." > > > > > > > > 2. "During the Clause 37/SGMII as the auto-negotiation link timer > > > > operates with a faster clock in the 2.5G mode, the timeout duration > > > > reduces by a factor of 2.5. To restore the standard specified timeout > > > > period, the respective registers must be re-programmed." > > > > > > > > I guess the entire 2.5G-thing understanding could be generalized by > > > > the next sentence from the HW manual: "The 2.5G mode of operation is > > > > functionally the same as 1000BASE-X/KX mode, except that the > > > > clock-rate is 2.5 times the original rate. In this mode, the > > > > Serdes/PHY operates at a serial baud-rate of 3.125 Gbps and DWC_xpcs > > > > data-path and the GMII interface to MAC operates at 312.5 MHz (instead > > > > of 125 MHz)." Thus here is another info regarding AN in that context: > > > > > > > > 3. "The DWC_xpcs operates either in 10/100/1000Mbps rate or > > > > 25/250/2500Mbps rates respectively with SGMII auto-negotiation. The > > > > DWC_xpcs cannot support switching or negotiation between 1G and 2.5G > > > > rates using auto-negotiation." > > > > > > Thanks for the clarification. > > > > > > So this hardware, just like Marvell hardware, operates 2500BASE-X merely > > > by up-clocking, and all the features that were available at 1000BASE-X > > > are also available at 2500BASE-X, including the in-band signalling. > > > > > > Therefore, I think rather than disabling AN outright, the > > > PHYLINK_PCS_NEG_* mode passed in should be checked to determine whether > > > inband should be used or not. > > > > Just an additional note which might be relevant in the context of the > > DW XPCS 1G/2.5G C37 AN. The C37 auto-negotiation feature will be > > unavailable for 1000BASE-X and thus for 2500BASE-X if the IP-core is > > synthesized with no support of one. It is determined by the CL37_AN > > IP-core synthesize parameter state: > > > > Enable SGMII Clause 37 | Description: Configures DWC_xpcs to support the > > Auto-Negotiation | Clause 37 auto-negotiation > > | > > | Dependencies: This option is available in the > > | following configurations: > > | - SUPPORT_1G = Enabled > > | - MAIN_MODE = Backplane Ethernet PCS and > > | BACKPLANE_ETH_CONFIG = KX_Only or KX4_KX > > | or KR_KX or KR_KX4_KX mode > > | > > | Default Value: Enabled for configurations with > > | MAIN_MODE = 1000BASEX-Only PCS and Disabled > > | for all other configurations > > | > > | HDL Parameter Name: CL37_AN > > > > So depending on the particular (vendor-specific) device configuration > > the C37 AN might still unavailable even though the device supports the > > 1000BASE-X and 2500BASE-X interfaces. > > Thanks. I guess there's no way to read the CL37_AN setting from > software? I can't be 100% sure because my HW doesn't support neither 1000Base-X/SGMII nor C37 AN to test out what is described further, but AFAICS from the HW manual it can be done by either on the next ways: 1. There is Vendor-Specific 1 MMD #30 (0x1e) which controls other MMDs present in the device configuration. It exposes a register 0x0009 "SR Control MMD Control Register" which aside with some stuff can be used to switch on/off device MMDs including the MII MMD mapped to the Vendor-Specific 2 MMD #31 (0x1f). Field 2 in that CSR is called MII_MMD_EN and is available as RW only if "CL37_AN = Enabled" otherwise it's RO and is supposed to contain the default value 0 (which is the case for my device). Although further, in the MII MMD Standard Registers (SR) description, HW-manual says that "The MII registers are present in 1000BASEX-Only PCS configurations or configurations with 1G Support (1000BASE-X support) and Clause 37 auto-negotiation support." It sounds vague and from some point of view contradicting to what is said in the MII_MMD_EN field description - whether C37 AN availability is required to have the MII registers available. 2. If option 1 turns to be not working to detect the C37 AN availability I guess it can be done by means of the 0x0001 CSR "SR MII MMD Status Register" exposed in the MII MMD #31 (0x1f). It has AN_ABL bit 3 "Auto-negotiation Ability". The bit description says that it's RO and indicates: "1: The DWC_xpcs is able to perform auto-negotiation." and "0: The DWC_xpcs is not able to perform auto-negotiation." But it also says that "The DWC_xpcs always returns this bit as 1.", which most likely implicitly confirms the option 1 described before. So in case if MII MMD #31 is available that flag will be always 1, otherwise if MII MMD #31 is fully unavailable that flag will return 0 despite to what is said in its description. -Serge(y) > > -- > RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ > FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last! ^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2023-09-26 19:41 UTC | newest] Thread overview: 8+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2023-09-25 7:51 [PATCH net-next] net: pcs: xpcs: Add 2500BASE-X case in get state for XPCS drivers Raju Lakkaraju 2023-09-26 11:39 ` Serge Semin 2023-09-26 11:45 ` Russell King (Oracle) 2023-09-26 12:09 ` Serge Semin 2023-09-26 14:46 ` Russell King (Oracle) 2023-09-26 15:27 ` Serge Semin 2023-09-26 15:47 ` Russell King (Oracle) 2023-09-26 19:40 ` Serge Semin
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