From:   Andrew Halaney <ahalaney@redhat.com>
To:     linux-kernel@vger.kernel.org
Cc:     agross@kernel.org, andersson@kernel.org, konrad.dybcio@linaro.org,
        davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
        pabeni@redhat.com, robh+dt@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, vkoul@kernel.org,
        bhupesh.sharma@linaro.org, mturquette@baylibre.com,
        sboyd@kernel.org, peppe.cavallaro@st.com,
        alexandre.torgue@foss.st.com, joabreu@synopsys.com,
        mcoquelin.stm32@gmail.com, richardcochran@gmail.com,
        linux@armlinux.org.uk, veekhee@apple.com,
        tee.min.tan@linux.intel.com, mohammad.athari.ismail@intel.com,
        jonathanh@nvidia.com, ruppala@nvidia.com, bmasney@redhat.com,
        andrey.konovalov@linaro.org, linux-arm-msm@vger.kernel.org,
        netdev@vger.kernel.org, devicetree@vger.kernel.org,
        linux-clk@vger.kernel.org,
        linux-stm32@st-md-mailman.stormreply.com,
        linux-arm-kernel@lists.infradead.org, ncai@quicinc.com,
        jsuraj@qti.qualcomm.com, hisunil@quicinc.com,
        Andrew Halaney <ahalaney@redhat.com>
Subject: [PATCH net-next 09/11] net: ethernet: stmmac: dwmac-qcom-ethqos: Respect phy-mode and TX delay
Date:   Mon, 13 Mar 2023 11:56:18 -0500
Message-Id: <20230313165620.128463-10-ahalaney@redhat.com>
In-Reply-To: <20230313165620.128463-1-ahalaney@redhat.com>
References: <20230313165620.128463-1-ahalaney@redhat.com>
MIME-Version: 1.0
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Precedence: bulk

The driver currently sets a MAC TX delay of 2 ns no matter what the
phy-mode is. If the phy-mode indicates the phy is in charge of the
TX delay (rgmii-txid, rgmii-id), don't do it in the MAC.

Signed-off-by: Andrew Halaney <ahalaney@redhat.com>
---
 .../stmicro/stmmac/dwmac-qcom-ethqos.c        | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
index 732774645c1a..6f272cae330d 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
@@ -279,6 +279,16 @@ static int ethqos_dll_configure(struct qcom_ethqos *ethqos)
 
 static int ethqos_rgmii_macro_init(struct qcom_ethqos *ethqos)
 {
+	int phy_mode;
+	int phase_shift;
+
+	/* Determine if the PHY adds a 2 ns TX delay or the MAC handles it */
+	phy_mode = device_get_phy_mode(&ethqos->pdev->dev);
+	if (phy_mode == PHY_INTERFACE_MODE_RGMII_ID || phy_mode == PHY_INTERFACE_MODE_RGMII_TXID)
+		phase_shift = 0;
+	else
+		phase_shift = RGMII_CONFIG2_TX_CLK_PHASE_SHIFT_EN;
+
 	/* Disable loopback mode */
 	rgmii_updatel(ethqos, RGMII_CONFIG2_TX_TO_RX_LOOPBACK_EN,
 		      0, RGMII_IO_MACRO_CONFIG2);
@@ -300,9 +310,9 @@ static int ethqos_rgmii_macro_init(struct qcom_ethqos *ethqos)
 			      RGMII_CONFIG_PROG_SWAP, RGMII_IO_MACRO_CONFIG);
 		rgmii_updatel(ethqos, RGMII_CONFIG2_DATA_DIVIDE_CLK_SEL,
 			      0, RGMII_IO_MACRO_CONFIG2);
+
 		rgmii_updatel(ethqos, RGMII_CONFIG2_TX_CLK_PHASE_SHIFT_EN,
-			      RGMII_CONFIG2_TX_CLK_PHASE_SHIFT_EN,
-			      RGMII_IO_MACRO_CONFIG2);
+				  phase_shift, RGMII_IO_MACRO_CONFIG2);
 		rgmii_updatel(ethqos, RGMII_CONFIG2_RSVD_CONFIG15,
 			      0, RGMII_IO_MACRO_CONFIG2);
 		rgmii_updatel(ethqos, RGMII_CONFIG2_RX_PROG_SWAP,
@@ -336,8 +346,7 @@ static int ethqos_rgmii_macro_init(struct qcom_ethqos *ethqos)
 		rgmii_updatel(ethqos, RGMII_CONFIG2_DATA_DIVIDE_CLK_SEL,
 			      0, RGMII_IO_MACRO_CONFIG2);
 		rgmii_updatel(ethqos, RGMII_CONFIG2_TX_CLK_PHASE_SHIFT_EN,
-			      RGMII_CONFIG2_TX_CLK_PHASE_SHIFT_EN,
-			      RGMII_IO_MACRO_CONFIG2);
+				  phase_shift, RGMII_IO_MACRO_CONFIG2);
 		rgmii_updatel(ethqos, RGMII_CONFIG_MAX_SPD_PRG_2,
 			      BIT(6), RGMII_IO_MACRO_CONFIG);
 		rgmii_updatel(ethqos, RGMII_CONFIG2_RSVD_CONFIG15,
@@ -375,7 +384,7 @@ static int ethqos_rgmii_macro_init(struct qcom_ethqos *ethqos)
 		rgmii_updatel(ethqos, RGMII_CONFIG2_DATA_DIVIDE_CLK_SEL,
 			      0, RGMII_IO_MACRO_CONFIG2);
 		rgmii_updatel(ethqos, RGMII_CONFIG2_TX_CLK_PHASE_SHIFT_EN,
-			      0, RGMII_IO_MACRO_CONFIG2);
+				  phase_shift, RGMII_IO_MACRO_CONFIG2);
 		rgmii_updatel(ethqos, RGMII_CONFIG_MAX_SPD_PRG_9,
 			      BIT(12) | GENMASK(9, 8),
 			      RGMII_IO_MACRO_CONFIG);
-- 
2.39.2