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From:   Michael Walle <michael@walle.cc>
Date:   Wed, 28 Dec 2022 00:07:24 +0100
Subject: [PATCH RFC net-next v2 08/12] net: ethernet: freescale: xgmac:
 Separate C22 and C45 transactions for xgmac
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Message-Id: <20221227-v6-2-rc1-c45-seperation-v2-8-ddb37710e5a7@walle.cc>
References: <20221227-v6-2-rc1-c45-seperation-v2-0-ddb37710e5a7@walle.cc>
In-Reply-To: <20221227-v6-2-rc1-c45-seperation-v2-0-ddb37710e5a7@walle.cc>
To:     Heiner Kallweit <hkallweit1@gmail.com>,
        Russell King <linux@armlinux.org.uk>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Jose Abreu <Jose.Abreu@synopsys.com>,
        Sergey Shtylyov <s.shtylyov@omp.ru>,
        Wei Fang <wei.fang@nxp.com>,
        Shenwei Wang <shenwei.wang@nxp.com>,
        Clark Wang <xiaoning.wang@nxp.com>,
        NXP Linux Team <linux-imx@nxp.com>,
        Sean Wang <sean.wang@mediatek.com>,
        Landen Chao <Landen.Chao@mediatek.com>,
        DENG Qingfang <dqfext@gmail.com>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Vladimir Oltean <olteanv@gmail.com>,
        Matthias Brugger <matthias.bgg@gmail.com>
Cc:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-renesas-soc@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        linux-mediatek@lists.infradead.org, Andrew Lunn <andrew@lunn.ch>,
        Geert Uytterhoeven <geert+renesas@glider.be>,
        Michael Walle <michael@walle.cc>
Precedence: bulk

From: Andrew Lunn <andrew@lunn.ch>

The xgmac MDIO bus driver can perform both C22 and C45 transfers.
Create separate functions for each and register the C45 versions using
the new API calls where appropriate.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Michael Walle <michael@walle.cc>
---
v2:
 - [al] Move the masking of regnum into the variable declarations
 - [al] Remove a couple of blank lines
---
 drivers/net/ethernet/freescale/xgmac_mdio.c | 150 +++++++++++++++++++++-------
 1 file changed, 113 insertions(+), 37 deletions(-)

diff --git a/drivers/net/ethernet/freescale/xgmac_mdio.c b/drivers/net/ethernet/freescale/xgmac_mdio.c
index d7d39a58cd80..1861cf14f4d7 100644
--- a/drivers/net/ethernet/freescale/xgmac_mdio.c
+++ b/drivers/net/ethernet/freescale/xgmac_mdio.c
@@ -128,30 +128,57 @@ static int xgmac_wait_until_done(struct device *dev,
 	return 0;
 }
 
-/*
- * Write value to the PHY for this device to the register at regnum,waiting
+/* Write value to the PHY for this device to the register at regnum,waiting
  * until the write is done before it returns.  All PHY configuration has to be
  * done through the TSEC1 MIIM regs.
  */
-static int xgmac_mdio_write(struct mii_bus *bus, int phy_id, int regnum, u16 value)
+static int xgmac_mdio_write_c22(struct mii_bus *bus, int phy_id, int regnum,
+				u16 value)
 {
 	struct mdio_fsl_priv *priv = (struct mdio_fsl_priv *)bus->priv;
 	struct tgec_mdio_controller __iomem *regs = priv->mdio_base;
-	uint16_t dev_addr;
+	bool endian = priv->is_little_endian;
+	u16 dev_addr = regnum & 0x1f;
 	u32 mdio_ctl, mdio_stat;
 	int ret;
+
+	mdio_stat = xgmac_read32(&regs->mdio_stat, endian);
+	mdio_stat &= ~MDIO_STAT_ENC;
+	xgmac_write32(mdio_stat, &regs->mdio_stat, endian);
+
+	ret = xgmac_wait_until_free(&bus->dev, regs, endian);
+	if (ret)
+		return ret;
+
+	/* Set the port and dev addr */
+	mdio_ctl = MDIO_CTL_PORT_ADDR(phy_id) | MDIO_CTL_DEV_ADDR(dev_addr);
+	xgmac_write32(mdio_ctl, &regs->mdio_ctl, endian);
+
+	/* Write the value to the register */
+	xgmac_write32(MDIO_DATA(value), &regs->mdio_data, endian);
+
+	ret = xgmac_wait_until_done(&bus->dev, regs, endian);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+/* Write value to the PHY for this device to the register at regnum,waiting
+ * until the write is done before it returns.  All PHY configuration has to be
+ * done through the TSEC1 MIIM regs.
+ */
+static int xgmac_mdio_write_c45(struct mii_bus *bus, int phy_id, int dev_addr,
+				int regnum, u16 value)
+{
+	struct mdio_fsl_priv *priv = (struct mdio_fsl_priv *)bus->priv;
+	struct tgec_mdio_controller __iomem *regs = priv->mdio_base;
 	bool endian = priv->is_little_endian;
+	u32 mdio_ctl, mdio_stat;
+	int ret;
 
 	mdio_stat = xgmac_read32(&regs->mdio_stat, endian);
-	if (regnum & MII_ADDR_C45) {
-		/* Clause 45 (ie 10G) */
-		dev_addr = (regnum >> 16) & 0x1f;
-		mdio_stat |= MDIO_STAT_ENC;
-	} else {
-		/* Clause 22 (ie 1G) */
-		dev_addr = regnum & 0x1f;
-		mdio_stat &= ~MDIO_STAT_ENC;
-	}
+	mdio_stat |= MDIO_STAT_ENC;
 
 	xgmac_write32(mdio_stat, &regs->mdio_stat, endian);
 
@@ -164,13 +191,11 @@ static int xgmac_mdio_write(struct mii_bus *bus, int phy_id, int regnum, u16 val
 	xgmac_write32(mdio_ctl, &regs->mdio_ctl, endian);
 
 	/* Set the register address */
-	if (regnum & MII_ADDR_C45) {
-		xgmac_write32(regnum & 0xffff, &regs->mdio_addr, endian);
+	xgmac_write32(regnum & 0xffff, &regs->mdio_addr, endian);
 
-		ret = xgmac_wait_until_free(&bus->dev, regs, endian);
-		if (ret)
-			return ret;
-	}
+	ret = xgmac_wait_until_free(&bus->dev, regs, endian);
+	if (ret)
+		return ret;
 
 	/* Write the value to the register */
 	xgmac_write32(MDIO_DATA(value), &regs->mdio_data, endian);
@@ -182,31 +207,82 @@ static int xgmac_mdio_write(struct mii_bus *bus, int phy_id, int regnum, u16 val
 	return 0;
 }
 
-/*
- * Reads from register regnum in the PHY for device dev, returning the value.
+/* Reads from register regnum in the PHY for device dev, returning the value.
  * Clears miimcom first.  All PHY configuration has to be done through the
  * TSEC1 MIIM regs.
  */
-static int xgmac_mdio_read(struct mii_bus *bus, int phy_id, int regnum)
+static int xgmac_mdio_read_c22(struct mii_bus *bus, int phy_id, int regnum)
 {
 	struct mdio_fsl_priv *priv = (struct mdio_fsl_priv *)bus->priv;
 	struct tgec_mdio_controller __iomem *regs = priv->mdio_base;
+	bool endian = priv->is_little_endian;
+	u16 dev_addr = regnum & 0x1f;
 	unsigned long flags;
-	uint16_t dev_addr;
 	uint32_t mdio_stat;
 	uint32_t mdio_ctl;
 	int ret;
-	bool endian = priv->is_little_endian;
 
 	mdio_stat = xgmac_read32(&regs->mdio_stat, endian);
-	if (regnum & MII_ADDR_C45) {
-		dev_addr = (regnum >> 16) & 0x1f;
-		mdio_stat |= MDIO_STAT_ENC;
+	mdio_stat &= ~MDIO_STAT_ENC;
+	xgmac_write32(mdio_stat, &regs->mdio_stat, endian);
+
+	ret = xgmac_wait_until_free(&bus->dev, regs, endian);
+	if (ret)
+		return ret;
+
+	/* Set the Port and Device Addrs */
+	mdio_ctl = MDIO_CTL_PORT_ADDR(phy_id) | MDIO_CTL_DEV_ADDR(dev_addr);
+	xgmac_write32(mdio_ctl, &regs->mdio_ctl, endian);
+
+	if (priv->has_a009885)
+		/* Once the operation completes, i.e. MDIO_STAT_BSY clears, we
+		 * must read back the data register within 16 MDC cycles.
+		 */
+		local_irq_save(flags);
+
+	/* Initiate the read */
+	xgmac_write32(mdio_ctl | MDIO_CTL_READ, &regs->mdio_ctl, endian);
+
+	ret = xgmac_wait_until_done(&bus->dev, regs, endian);
+	if (ret)
+		goto irq_restore;
+
+	/* Return all Fs if nothing was there */
+	if ((xgmac_read32(&regs->mdio_stat, endian) & MDIO_STAT_RD_ER) &&
+	    !priv->has_a011043) {
+		dev_dbg(&bus->dev,
+			"Error while reading PHY%d reg at %d.%d\n",
+			phy_id, dev_addr, regnum);
+		ret = 0xffff;
 	} else {
-		dev_addr = regnum & 0x1f;
-		mdio_stat &= ~MDIO_STAT_ENC;
+		ret = xgmac_read32(&regs->mdio_data, endian) & 0xffff;
+		dev_dbg(&bus->dev, "read %04x\n", ret);
 	}
 
+irq_restore:
+	if (priv->has_a009885)
+		local_irq_restore(flags);
+
+	return ret;
+}
+
+/* Reads from register regnum in the PHY for device dev, returning the value.
+ * Clears miimcom first.  All PHY configuration has to be done through the
+ * TSEC1 MIIM regs.
+ */
+static int xgmac_mdio_read_c45(struct mii_bus *bus, int phy_id, int dev_addr,
+			       int regnum)
+{
+	struct mdio_fsl_priv *priv = (struct mdio_fsl_priv *)bus->priv;
+	struct tgec_mdio_controller __iomem *regs = priv->mdio_base;
+	bool endian = priv->is_little_endian;
+	u32 mdio_stat, mdio_ctl;
+	unsigned long flags;
+	int ret;
+
+	mdio_stat = xgmac_read32(&regs->mdio_stat, endian);
+	mdio_stat |= MDIO_STAT_ENC;
+
 	xgmac_write32(mdio_stat, &regs->mdio_stat, endian);
 
 	ret = xgmac_wait_until_free(&bus->dev, regs, endian);
@@ -218,13 +294,11 @@ static int xgmac_mdio_read(struct mii_bus *bus, int phy_id, int regnum)
 	xgmac_write32(mdio_ctl, &regs->mdio_ctl, endian);
 
 	/* Set the register address */
-	if (regnum & MII_ADDR_C45) {
-		xgmac_write32(regnum & 0xffff, &regs->mdio_addr, endian);
+	xgmac_write32(regnum & 0xffff, &regs->mdio_addr, endian);
 
-		ret = xgmac_wait_until_free(&bus->dev, regs, endian);
-		if (ret)
-			return ret;
-	}
+	ret = xgmac_wait_until_free(&bus->dev, regs, endian);
+	if (ret)
+		return ret;
 
 	if (priv->has_a009885)
 		/* Once the operation completes, i.e. MDIO_STAT_BSY clears, we
@@ -326,8 +400,10 @@ static int xgmac_mdio_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	bus->name = "Freescale XGMAC MDIO Bus";
-	bus->read = xgmac_mdio_read;
-	bus->write = xgmac_mdio_write;
+	bus->read = xgmac_mdio_read_c22;
+	bus->write = xgmac_mdio_write_c22;
+	bus->read_c45 = xgmac_mdio_read_c45;
+	bus->write_c45 = xgmac_mdio_write_c45;
 	bus->parent = &pdev->dev;
 	bus->probe_capabilities = MDIOBUS_C22_C45;
 	snprintf(bus->id, MII_BUS_ID_SIZE, "%pa", &res->start);

-- 
2.30.2