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References: <20230118061701.30047-1-yanhong.wang@starfivetech.com> <20230118061701.30047-7-yanhong.wang@starfivetech.com>
In-Reply-To: <20230118061701.30047-7-yanhong.wang@starfivetech.com>
From:   Emil Renner Berthing <emil.renner.berthing@canonical.com>
Date:   Mon, 20 Feb 2023 15:22:18 +0100
Message-ID: <CAJM55Z9=wXxHXLHhLK1H2H2PnLv4Z+FiQPVd_+gtPss+P01MRg@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>
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Precedence: bulk

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.

> +                       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
>
>
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