RE: [RFC PATCH 0/2] net: ethernet: Add support for gmii2rgmii converter
Hi Andrew, > On Fri, Jul 01, 2016 at 11:50:10AM +0530, Kedareswara rao Appana wrote: > > This patch series does the following > > ---> Add support for gmii2rgmii converter. > > How generic is this gmii2rgmii IP block? Could it be used with any GMII and > RGMII device? This converter does GMII2RGMII conversion. This can be used with any MAC which has shared MDIO with external PHY And this Converter. This Converter IP is validated for MACB. But it should work with any MAC which has shared MDIO bus (I mean single MDIO multiple PHYS)... This converter works like below MACB <==> GMII2RGMII <==> RGMII_PHY MDIO<> GMII2RGMII MCAB<===> <> RGMII Using MACB MDIO bus we can access both the converter and the external PHY. We need to program the line speed of the converter during run time based on the External phy negotiated speed. MDIO interface is used to set operating speed (line speed) The converter has only one register (0x10) that we need to program to set the operating speed. The composition of this register is similar to the IEEE standard 802.3 MDIO control register 0x0. Please let me know if you still not clear about how this converter works. > > Should it be placed in drivers/net/phy, so making it easier to reuse? Ok will move it drivers/net/phy folder in the next version... > > Also, Russell Kings phylink might be a more natural structure for this. It is > hard to > know when those patches will land, but it might be worth looking at. Ok sure will take a look at this series once posted... Regards, Kedar. > >Andrew
RE: [RFC PATCH 0/2] net: ethernet: Add support for gmii2rgmii converter
Hi Florian, Thanks for the review... > Le 30/06/2016 23:20, Kedareswara rao Appana a écrit : > > This patch series does the following > > ---> Add support for gmii2rgmii converter. > > ---> Add support for gmii2rgmii converter in the macb driver. > > > > Earlier sent one RFC patch https://patchwork.kernel.org/patch/9186615/ > > which includes converter related stuff also in macb driver. > > This patch series fixes this issue. > > This still seems very adhoc and not completely explained. Can you clarify how > the gmmi2rgmii converter gets used? Sorry I should have been explained it clearly in the patch. Will fix it in the v2. This converter works like below MACB <==> GMII2RGMII <==> RGMII_PHY MDIO<> GMII2RGMII MCAB<===> <> RGMII Using MACB MDIO bus we can access both the converter and the external PHY. We need to program the line speed of the converter during run time based on the External phy negotiated speed. MDIO interface is used to set operating speed (line speed) The converter has only one register (0x10) that we need to program to set the operating speed. The composition of this register is similar to the IEEE standard 802.3 MDIO control register 0x0. Please let me know if you still need not clear with how this converter works. IP data sheet is available here @ http://www.xilinx.com/support/documentation/ip_documentation/gmii_to_rgmii/v3_0/pg160-gmii-to-rgmii.pdf > > Is the expectation that a MACB Ethernet adapter will be connected to a RGMII > PHY like this: > > MACB <=> GMII2RGMII <=> RGMII PHY > MACB MDIO <===> RGMII_PHY > > and still have the ability to control both the PHY device's MDIO registers > and the > GMII2RGMII converter and we need to make sure both have matching settings, > or is it something like this: > > MACB <=> GMII2RGMII <=> RGMII PHY > MACB MDIO unconnected > > and we lose the ability to query the PHY via MDIO? > > As Nicolas pointed out, providing a binding documentation update may help > reviewers understand what is being accomplished here. Sure will fix in v2. Regards, Kedar.
Re: [RFC PATCH 0/2] net: ethernet: Add support for gmii2rgmii converter
On Fri, Jul 01, 2016 at 11:50:10AM +0530, Kedareswara rao Appana wrote: > This patch series does the following > ---> Add support for gmii2rgmii converter. How generic is this gmii2rgmii IP block? Could it be used with any GMII and RGMII device? Should it be placed in drivers/net/phy, so making it easier to reuse? Also, Russell Kings phylink might be a more natural structure for this. It is hard to know when those patches will land, but it might be worth looking at. Andrew
Re: [RFC PATCH 0/2] net: ethernet: Add support for gmii2rgmii converter
Le 30/06/2016 23:20, Kedareswara rao Appana a écrit : > This patch series does the following > ---> Add support for gmii2rgmii converter. > ---> Add support for gmii2rgmii converter in the macb driver. > > Earlier sent one RFC patch https://patchwork.kernel.org/patch/9186615/ > which includes converter related stuff also in macb driver. > This patch series fixes this issue. This still seems very adhoc and not completely explained. Can you clarify how the gmmi2rgmii converter gets used? Is the expectation that a MACB Ethernet adapter will be connected to a RGMII PHY like this: MACB <=> GMII2RGMII <=> RGMII PHY MACB MDIO <===> RGMII_PHY and still have the ability to control both the PHY device's MDIO registers and the GMII2RGMII converter and we need to make sure both have matching settings, or is it something like this: MACB <=> GMII2RGMII <=> RGMII PHY MACB MDIO unconnected and we lose the ability to query the PHY via MDIO? As Nicolas pointed out, providing a binding documentation update may help reviewers understand what is being accomplished here. Thanks! > > Kedareswara rao Appana (2): > net: ethernet: xilinx: Add gmii2rgmii converter support > net: macb: Add gmii2rgmii phy converter support > > drivers/net/ethernet/cadence/macb.c | 21 ++- > drivers/net/ethernet/cadence/macb.h |3 + > drivers/net/ethernet/xilinx/Kconfig |7 ++ > drivers/net/ethernet/xilinx/Makefile|1 + > drivers/net/ethernet/xilinx/xilinx_gmii2rgmii.c | 76 > +++ > include/linux/xilinx_gmii2rgmii.h | 24 +++ > 6 files changed, 131 insertions(+), 1 deletions(-) > create mode 100644 drivers/net/ethernet/xilinx/xilinx_gmii2rgmii.c > create mode 100644 include/linux/xilinx_gmii2rgmii.h > -- Florian
