MIME-Version: 1.0
References: <20230118061701.30047-1-yanhong.wang@starfivetech.com>
 <20230118061701.30047-7-yanhong.wang@starfivetech.com> <CAJM55Z9=wXxHXLHhLK1H2H2PnLv4Z+FiQPVd_+gtPss+P01MRg@mail.gmail.com>
In-Reply-To: <CAJM55Z9=wXxHXLHhLK1H2H2PnLv4Z+FiQPVd_+gtPss+P01MRg@mail.gmail.com>
From:   Emil Renner Berthing <emil.renner.berthing@canonical.com>
Date:   Mon, 20 Feb 2023 16:00:57 +0100
Message-ID: <CAJM55Z91Z277FB8O_P9VSEqjcPykvhrPOcvx6k05X5veNOo3Lw@mail.gmail.com>
Subject: Re: [PATCH v4 6/7] riscv: dts: starfive: jh7110: Add ethernet device node
To:     Yanhong Wang <yanhong.wang@starfivetech.com>
Cc:     linux-riscv@lists.infradead.org, netdev@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        "David S . Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Emil Renner Berthing <kernel@esmil.dk>,
        Richard Cochran <richardcochran@gmail.com>,
        Andrew Lunn <andrew@lunn.ch>,
        Heiner Kallweit <hkallweit1@gmail.com>,
        Peter Geis <pgwipeout@gmail.com>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Mon, 20 Feb 2023 at 15:22, Emil Renner Berthing
<emil.renner.berthing@canonical.com> wrote:
> On Wed, 18 Jan 2023 at 07:19, Yanhong Wang
> <yanhong.wang@starfivetech.com> wrote:
> > Add JH7110 ethernet device node to support gmac driver for the JH7110
> > RISC-V SoC.
> >
> > Signed-off-by: Yanhong Wang <yanhong.wang@starfivetech.com>
> > ---
> >  arch/riscv/boot/dts/starfive/jh7110.dtsi | 93 ++++++++++++++++++++++++
> >  1 file changed, 93 insertions(+)
> >
> > diff --git a/arch/riscv/boot/dts/starfive/jh7110.dtsi b/arch/riscv/boot/dts/starfive/jh7110.dtsi
> > index c22e8f1d2640..c6de6e3b1a25 100644
> > --- a/arch/riscv/boot/dts/starfive/jh7110.dtsi
> > +++ b/arch/riscv/boot/dts/starfive/jh7110.dtsi
> > @@ -433,5 +433,98 @@
> >                         reg-shift = <2>;
> >                         status = "disabled";
> >                 };
> > +
> > +               stmmac_axi_setup: stmmac-axi-config {
> > +                       snps,lpi_en;
> > +                       snps,wr_osr_lmt = <4>;
> > +                       snps,rd_osr_lmt = <4>;
> > +                       snps,blen = <256 128 64 32 0 0 0>;
> > +               };
> > +
> > +               gmac0: ethernet@16030000 {
> > +                       compatible = "starfive,jh7110-dwmac", "snps,dwmac-5.20";
> > +                       reg = <0x0 0x16030000 0x0 0x10000>;
> > +                       clocks = <&aoncrg JH7110_AONCLK_GMAC0_AXI>,
> > +                                <&aoncrg JH7110_AONCLK_GMAC0_AHB>,
> > +                                <&syscrg JH7110_SYSCLK_GMAC0_PTP>,
> > +                                <&aoncrg JH7110_AONCLK_GMAC0_TX>,
>
> The gmac0_tx clock is a mux that takes either the gmac0_gtxclk or
> rmii_rtx as parent. However it is then followed by an inverter that
> optionally inverts the clock, gmac0_tx_inv. I'm guessing this
> optionally inverted signal is what is actually used (otherwise why
> would the inverter exist), so I think this clock is what should be
> claimed here. Eg.
>     <&aoncrg JH7110_AONCLK_GMAC0_TX_INV>,
>
> Right now it works only because the inverted signal can't be gated
> (turned off) even when it's not claimed by any driver.
>
> > +                                <&syscrg JH7110_SYSCLK_GMAC0_GTXC>,
> > +                                <&syscrg JH7110_SYSCLK_GMAC0_GTXCLK>;
>
> Here the gmac0_gtxclk clock is the parent of the gmac0_gtxc, so
> claiming the gmac0_gtxc should be enough. Since the gmac0_gtxc is just
> a gate it should have the CLK_SET_RATE_PARENT flag set, so the driver
> can just change the rate of the child and it should propagate to the
> parent. In short I think claiming only the gmac0_gtxc clock should be
> enough here.

Oh and just for completeness. This also goes for gmac1 below, and
don't forget to update the yaml binding doc accordingly.

> > +                       clock-names = "stmmaceth", "pclk", "ptp_ref",
> > +                                               "tx", "gtxc", "gtx";
> > +                       resets = <&aoncrg JH7110_AONRST_GMAC0_AXI>,
> > +                                <&aoncrg JH7110_AONRST_GMAC0_AHB>;
> > +                       reset-names = "stmmaceth", "ahb";
> > +                       interrupts = <7>, <6>, <5>;
> > +                       interrupt-names = "macirq", "eth_wake_irq", "eth_lpi";
> > +                       phy-mode = "rgmii-id";
> > +                       snps,multicast-filter-bins = <64>;
> > +                       snps,perfect-filter-entries = <8>;
> > +                       rx-fifo-depth = <2048>;
> > +                       tx-fifo-depth = <2048>;
> > +                       snps,fixed-burst;
> > +                       snps,no-pbl-x8;
> > +                       snps,force_thresh_dma_mode;
> > +                       snps,axi-config = <&stmmac_axi_setup>;
> > +                       snps,tso;
> > +                       snps,en-tx-lpi-clockgating;
> > +                       snps,txpbl = <16>;
> > +                       snps,rxpbl = <16>;
> > +                       status = "disabled";
> > +                       phy-handle = <&phy0>;
> > +
> > +                       mdio0: mdio {
> > +                               #address-cells = <1>;
> > +                               #size-cells = <0>;
> > +                               compatible = "snps,dwmac-mdio";
> > +
> > +                               phy0: ethernet-phy@0 {
> > +                                       reg = <0>;
> > +                               };
> > +                       };
> > +               };
> > +
> > +               gmac1: ethernet@16040000 {
> > +                       compatible = "starfive,jh7110-dwmac", "snps,dwmac-5.20";
> > +                       reg = <0x0 0x16040000 0x0 0x10000>;
> > +                       clocks = <&syscrg JH7110_SYSCLK_GMAC1_AXI>,
> > +                                <&syscrg JH7110_SYSCLK_GMAC1_AHB>,
> > +                                <&syscrg JH7110_SYSCLK_GMAC1_PTP>,
> > +                                <&syscrg JH7110_SYSCLK_GMAC1_TX>,
> > +                                <&syscrg JH7110_SYSCLK_GMAC1_GTXC>,
> > +                                <&syscrg JH7110_SYSCLK_GMAC1_GTXCLK>;
> > +                       clock-names = "stmmaceth", "pclk", "ptp_ref",
> > +                                       "tx", "gtxc", "gtx";
> > +                       resets = <&syscrg JH7110_SYSRST_GMAC1_AXI>,
> > +                                <&syscrg JH7110_SYSRST_GMAC1_AHB>;
> > +                       reset-names = "stmmaceth", "ahb";
> > +                       interrupts = <78>, <77>, <76>;
> > +                       interrupt-names = "macirq", "eth_wake_irq", "eth_lpi";
> > +                       phy-mode = "rgmii-id";
> > +                       snps,multicast-filter-bins = <64>;
> > +                       snps,perfect-filter-entries = <8>;
> > +                       rx-fifo-depth = <2048>;
> > +                       tx-fifo-depth = <2048>;
> > +                       snps,fixed-burst;
> > +                       snps,no-pbl-x8;
> > +                       snps,force_thresh_dma_mode;
> > +                       snps,axi-config = <&stmmac_axi_setup>;
> > +                       snps,tso;
> > +                       snps,en-tx-lpi-clockgating;
> > +                       snps,txpbl = <16>;
> > +                       snps,rxpbl = <16>;
> > +                       status = "disabled";
> > +                       phy-handle = <&phy1>;
> > +
> > +                       mdio1: mdio {
> > +                               #address-cells = <1>;
> > +                               #size-cells = <0>;
> > +                               compatible = "snps,dwmac-mdio";
> > +
> > +                               phy1: ethernet-phy@1 {
> > +                                       reg = <1>;
> > +                               };
> > +                       };
> > +               };
> >         };
> >  };
> > --
> > 2.17.1
> >
> >
> > _______________________________________________
> > linux-riscv mailing list
> > linux-riscv@lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/linux-riscv