From: Geert Uytterhoeven <geert+renesas@glider.be> To: Magnus Damm <magnus.damm@gmail.com> Cc: Biju Das <biju.das.jz@bp.renesas.com>, Adam Ford <aford173@gmail.com>, Florian Fainelli <f.fainelli@gmail.com>, Andrew Lunn <andrew@lunn.ch>, Heiner Kallweit <hkallweit1@gmail.com>, Russell King <linux@armlinux.org.uk>, Grygorii Strashko <grygorii.strashko@ti.com>, linux-renesas-soc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, netdev@vger.kernel.org, devicetree@vger.kernel.org, Geert Uytterhoeven <geert+renesas@glider.be> Subject: [PATCH 0/9] renesas: Add compatible properties to Ethernet PHY nodes Date: Thu, 9 Sep 2021 10:49:36 +0200 [thread overview] Message-ID: <cover.1631174218.git.geert+renesas@glider.be> (raw) Hi all, If an Ethernet PHY reset is asserted when the Ethernet driver is initialized, the PHY cannot be probed: mdio_bus ee700000.ethernet-ffffffff: MDIO device at address 1 is missing This happens because the Linux PHY subsystem tries to read the PHY Identifier registers before handling PHY reset. Hence if the PHY reset was asserted before, identification fails. An easy way to reproduce this issue is by using kexec to launch a new kernel (the PHY reset will be asserted before starting the new kernel), or by unbinding and rebinding the Ethernet driver (the PHY reset will be asserted during unbind), e.g. on koelsch: echo ee700000.ethernet > /sys/bus/platform/drivers/sh-eth/unbind $ echo ee700000.ethernet > /sys/bus/platform/drivers/sh-eth/bind The recommended approach[1][2] seems to be working around this issue by adding compatible values to all ethernet-phy nodes, so Linux can identify the PHY at any time, without reading the PHY ID from the device, and regardless of the state of the PHY reset line. Hence this patch series adds such compatible values to all Ethernet PHY subnodes representing PHYs on all boards with Renesas ARM and ARM64 SoCs. For easier review, I have split the series in one patch per PHY model. On most boards, I could verify the actual PHY ID at runtime[3], on other boards I had to resort to schematics. Kexec and Ethernet driver rebind have been tested on Koelsch and Salvator-XS. I plan to queue these in renesas-devel for v5.16. Thanks for your comments! [1] "Re: [PATCH] RFC: net: phy: of phys probe/reset issue" https://lore.kernel.org/r/ade12434-adf2-6ea7-24ce-ce45ad2e1b5e@gmail.com/ [2] "PHY reset may still be asserted during MDIO probe" https://lore.kernel.org/r/CAMuHMdXno2OUHqsAfO0z43JmGkFehD+FJ2dEjEsr_P53oAAPxA@mail.gmail.com [3] The easiest way to obtain the PHY ID is by adding a debug print to drivers/net/phy/phy_device.c:get_phy_c22_id(), _before_ applying this patch. Geert Uytterhoeven (9): ARM: dts: renesas: Add compatible properties to KSZ8041 Ethernet PHYs ARM: dts: renesas: Add compatible properties to KSZ8081 Ethernet PHYs ARM: dts: renesas: Add compatible properties to KSZ9031 Ethernet PHYs iARM: dts: renesas: Add compatible properties to LAN8710A Ethernet PHYs ARM: dts: renesas: Add compatible properties to RTL8201FL Ethernet PHYs ARM: dts: renesas: Add compatible properties to uPD6061x Ethernet PHYs arm64: dts: renesas: Add compatible properties to AR8031 Ethernet PHYs arm64: dts: renesas: Add compatible properties to KSZ9031 Ethernet PHYs arm64: dts: renesas: Add compatible properties to RTL8211E Ethernet PHYs arch/arm/boot/dts/iwg20d-q7-common.dtsi | 2 ++ arch/arm/boot/dts/r7s72100-genmai.dts | 2 ++ arch/arm/boot/dts/r7s72100-gr-peach.dts | 2 ++ arch/arm/boot/dts/r7s72100-rskrza1.dts | 2 ++ arch/arm/boot/dts/r7s9210-rza2mevb.dts | 2 ++ arch/arm/boot/dts/r8a7740-armadillo800eva.dts | 2 ++ arch/arm/boot/dts/r8a7742-iwg21d-q7-dbcm-ca.dts | 2 ++ arch/arm/boot/dts/r8a7742-iwg21d-q7.dts | 2 ++ arch/arm/boot/dts/r8a7743-sk-rzg1m.dts | 2 ++ arch/arm/boot/dts/r8a7745-iwg22d-sodimm.dts | 2 ++ arch/arm/boot/dts/r8a7745-sk-rzg1e.dts | 2 ++ arch/arm/boot/dts/r8a77470-iwg23s-sbc.dts | 2 ++ arch/arm/boot/dts/r8a7790-lager.dts | 2 ++ arch/arm/boot/dts/r8a7790-stout.dts | 2 ++ arch/arm/boot/dts/r8a7791-koelsch.dts | 2 ++ arch/arm/boot/dts/r8a7791-porter.dts | 2 ++ arch/arm/boot/dts/r8a7793-gose.dts | 2 ++ arch/arm/boot/dts/r8a7794-alt.dts | 2 ++ arch/arm/boot/dts/r8a7794-silk.dts | 2 ++ arch/arm64/boot/dts/renesas/beacon-renesom-som.dtsi | 2 ++ arch/arm64/boot/dts/renesas/cat875.dtsi | 2 ++ arch/arm64/boot/dts/renesas/draak.dtsi | 2 ++ arch/arm64/boot/dts/renesas/ebisu.dtsi | 2 ++ arch/arm64/boot/dts/renesas/hihope-rzg2-ex.dtsi | 2 ++ arch/arm64/boot/dts/renesas/r8a77970-eagle.dts | 2 ++ arch/arm64/boot/dts/renesas/r8a77970-v3msk.dts | 2 ++ arch/arm64/boot/dts/renesas/r8a77980-condor.dts | 2 ++ arch/arm64/boot/dts/renesas/r8a77980-v3hsk.dts | 2 ++ arch/arm64/boot/dts/renesas/r8a779a0-falcon.dts | 2 ++ arch/arm64/boot/dts/renesas/salvator-common.dtsi | 2 ++ arch/arm64/boot/dts/renesas/ulcb.dtsi | 2 ++ 31 files changed, 62 insertions(+) -- 2.25.1 Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
WARNING: multiple messages have this Message-ID (diff)
From: Geert Uytterhoeven <geert+renesas@glider.be> To: Magnus Damm <magnus.damm@gmail.com> Cc: Biju Das <biju.das.jz@bp.renesas.com>, Adam Ford <aford173@gmail.com>, Florian Fainelli <f.fainelli@gmail.com>, Andrew Lunn <andrew@lunn.ch>, Heiner Kallweit <hkallweit1@gmail.com>, Russell King <linux@armlinux.org.uk>, Grygorii Strashko <grygorii.strashko@ti.com>, linux-renesas-soc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, netdev@vger.kernel.org, devicetree@vger.kernel.org, Geert Uytterhoeven <geert+renesas@glider.be> Subject: [PATCH 0/9] renesas: Add compatible properties to Ethernet PHY nodes Date: Thu, 9 Sep 2021 10:49:36 +0200 [thread overview] Message-ID: <cover.1631174218.git.geert+renesas@glider.be> (raw) Hi all, If an Ethernet PHY reset is asserted when the Ethernet driver is initialized, the PHY cannot be probed: mdio_bus ee700000.ethernet-ffffffff: MDIO device at address 1 is missing This happens because the Linux PHY subsystem tries to read the PHY Identifier registers before handling PHY reset. Hence if the PHY reset was asserted before, identification fails. An easy way to reproduce this issue is by using kexec to launch a new kernel (the PHY reset will be asserted before starting the new kernel), or by unbinding and rebinding the Ethernet driver (the PHY reset will be asserted during unbind), e.g. on koelsch: echo ee700000.ethernet > /sys/bus/platform/drivers/sh-eth/unbind $ echo ee700000.ethernet > /sys/bus/platform/drivers/sh-eth/bind The recommended approach[1][2] seems to be working around this issue by adding compatible values to all ethernet-phy nodes, so Linux can identify the PHY at any time, without reading the PHY ID from the device, and regardless of the state of the PHY reset line. Hence this patch series adds such compatible values to all Ethernet PHY subnodes representing PHYs on all boards with Renesas ARM and ARM64 SoCs. For easier review, I have split the series in one patch per PHY model. On most boards, I could verify the actual PHY ID at runtime[3], on other boards I had to resort to schematics. Kexec and Ethernet driver rebind have been tested on Koelsch and Salvator-XS. I plan to queue these in renesas-devel for v5.16. Thanks for your comments! [1] "Re: [PATCH] RFC: net: phy: of phys probe/reset issue" https://lore.kernel.org/r/ade12434-adf2-6ea7-24ce-ce45ad2e1b5e@gmail.com/ [2] "PHY reset may still be asserted during MDIO probe" https://lore.kernel.org/r/CAMuHMdXno2OUHqsAfO0z43JmGkFehD+FJ2dEjEsr_P53oAAPxA@mail.gmail.com [3] The easiest way to obtain the PHY ID is by adding a debug print to drivers/net/phy/phy_device.c:get_phy_c22_id(), _before_ applying this patch. Geert Uytterhoeven (9): ARM: dts: renesas: Add compatible properties to KSZ8041 Ethernet PHYs ARM: dts: renesas: Add compatible properties to KSZ8081 Ethernet PHYs ARM: dts: renesas: Add compatible properties to KSZ9031 Ethernet PHYs iARM: dts: renesas: Add compatible properties to LAN8710A Ethernet PHYs ARM: dts: renesas: Add compatible properties to RTL8201FL Ethernet PHYs ARM: dts: renesas: Add compatible properties to uPD6061x Ethernet PHYs arm64: dts: renesas: Add compatible properties to AR8031 Ethernet PHYs arm64: dts: renesas: Add compatible properties to KSZ9031 Ethernet PHYs arm64: dts: renesas: Add compatible properties to RTL8211E Ethernet PHYs arch/arm/boot/dts/iwg20d-q7-common.dtsi | 2 ++ arch/arm/boot/dts/r7s72100-genmai.dts | 2 ++ arch/arm/boot/dts/r7s72100-gr-peach.dts | 2 ++ arch/arm/boot/dts/r7s72100-rskrza1.dts | 2 ++ arch/arm/boot/dts/r7s9210-rza2mevb.dts | 2 ++ arch/arm/boot/dts/r8a7740-armadillo800eva.dts | 2 ++ arch/arm/boot/dts/r8a7742-iwg21d-q7-dbcm-ca.dts | 2 ++ arch/arm/boot/dts/r8a7742-iwg21d-q7.dts | 2 ++ arch/arm/boot/dts/r8a7743-sk-rzg1m.dts | 2 ++ arch/arm/boot/dts/r8a7745-iwg22d-sodimm.dts | 2 ++ arch/arm/boot/dts/r8a7745-sk-rzg1e.dts | 2 ++ arch/arm/boot/dts/r8a77470-iwg23s-sbc.dts | 2 ++ arch/arm/boot/dts/r8a7790-lager.dts | 2 ++ arch/arm/boot/dts/r8a7790-stout.dts | 2 ++ arch/arm/boot/dts/r8a7791-koelsch.dts | 2 ++ arch/arm/boot/dts/r8a7791-porter.dts | 2 ++ arch/arm/boot/dts/r8a7793-gose.dts | 2 ++ arch/arm/boot/dts/r8a7794-alt.dts | 2 ++ arch/arm/boot/dts/r8a7794-silk.dts | 2 ++ arch/arm64/boot/dts/renesas/beacon-renesom-som.dtsi | 2 ++ arch/arm64/boot/dts/renesas/cat875.dtsi | 2 ++ arch/arm64/boot/dts/renesas/draak.dtsi | 2 ++ arch/arm64/boot/dts/renesas/ebisu.dtsi | 2 ++ arch/arm64/boot/dts/renesas/hihope-rzg2-ex.dtsi | 2 ++ arch/arm64/boot/dts/renesas/r8a77970-eagle.dts | 2 ++ arch/arm64/boot/dts/renesas/r8a77970-v3msk.dts | 2 ++ arch/arm64/boot/dts/renesas/r8a77980-condor.dts | 2 ++ arch/arm64/boot/dts/renesas/r8a77980-v3hsk.dts | 2 ++ arch/arm64/boot/dts/renesas/r8a779a0-falcon.dts | 2 ++ arch/arm64/boot/dts/renesas/salvator-common.dtsi | 2 ++ arch/arm64/boot/dts/renesas/ulcb.dtsi | 2 ++ 31 files changed, 62 insertions(+) -- 2.25.1 Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next reply other threads:[~2021-09-09 8:50 UTC|newest] Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-09-09 8:49 Geert Uytterhoeven [this message] 2021-09-09 8:49 ` [PATCH 0/9] renesas: Add compatible properties to Ethernet PHY nodes Geert Uytterhoeven 2021-09-09 8:49 ` [PATCH 1/9] ARM: dts: renesas: Add compatible properties to KSZ8041 Ethernet PHYs Geert Uytterhoeven 2021-09-09 8:49 ` Geert Uytterhoeven 2021-09-09 8:49 ` [PATCH 2/9] ARM: dts: renesas: Add compatible properties to KSZ8081 " Geert Uytterhoeven 2021-09-09 8:49 ` Geert Uytterhoeven 2021-09-09 8:49 ` [PATCH 3/9] ARM: dts: renesas: Add compatible properties to KSZ9031 " Geert Uytterhoeven 2021-09-09 8:49 ` Geert Uytterhoeven 2021-09-23 11:41 ` Biju Das 2021-09-23 11:41 ` Biju Das 2021-09-09 8:49 ` [PATCH 4/9] iARM: dts: renesas: Add compatible properties to LAN8710A " Geert Uytterhoeven 2021-09-09 8:49 ` Geert Uytterhoeven 2021-09-09 8:49 ` [PATCH 5/9] ARM: dts: renesas: Add compatible properties to RTL8201FL " Geert Uytterhoeven 2021-09-09 8:49 ` Geert Uytterhoeven 2021-09-09 8:49 ` [PATCH 6/9] ARM: dts: renesas: Add compatible properties to uPD6061x " Geert Uytterhoeven 2021-09-09 8:49 ` Geert Uytterhoeven 2021-09-09 8:49 ` [PATCH 7/9] arm64: dts: renesas: Add compatible properties to AR8031 " Geert Uytterhoeven 2021-09-09 8:49 ` Geert Uytterhoeven 2021-09-09 8:49 ` [PATCH 8/9] arm64: dts: renesas: Add compatible properties to KSZ9031 " Geert Uytterhoeven 2021-09-09 8:49 ` Geert Uytterhoeven 2021-09-28 7:40 ` Geert Uytterhoeven 2021-09-28 7:40 ` Geert Uytterhoeven 2021-09-09 8:49 ` [PATCH 9/9] arm64: dts: renesas: Add compatible properties to RTL8211E " Geert Uytterhoeven 2021-09-09 8:49 ` Geert Uytterhoeven 2021-09-23 11:38 ` Biju Das 2021-09-23 11:38 ` Biju Das 2021-09-23 11:00 ` [PATCH 0/9] renesas: Add compatible properties to Ethernet PHY nodes Geert Uytterhoeven 2021-09-23 11:00 ` Geert Uytterhoeven 2021-09-23 14:09 ` Andrew Lunn 2021-09-23 14:09 ` Andrew Lunn
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=cover.1631174218.git.geert+renesas@glider.be \ --to=geert+renesas@glider.be \ --cc=aford173@gmail.com \ --cc=andrew@lunn.ch \ --cc=biju.das.jz@bp.renesas.com \ --cc=devicetree@vger.kernel.org \ --cc=f.fainelli@gmail.com \ --cc=grygorii.strashko@ti.com \ --cc=hkallweit1@gmail.com \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-renesas-soc@vger.kernel.org \ --cc=linux@armlinux.org.uk \ --cc=magnus.damm@gmail.com \ --cc=netdev@vger.kernel.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.