diff mbox series

[net-next,v2,3/3] enetc: Add ENETC PF level external MDIO support

Message ID 1550225414-12125-4-git-send-email-claudiu.manoil@nxp.com
State Changes Requested
Delegated to: David Miller
Headers show
Series enetc: Add mdio support and device tree nodes | expand

Commit Message

Claudiu Manoil Feb. 15, 2019, 10:10 a.m. UTC 
Each ENETC PF has its own MDIO interface, the corresponding
MDIO registers are mapped in the ENETC's Port register block.
The current patch adds a driver for these PF level MDIO buses,
so that each PF can manage directly its own external link.

Signed-off-by: Alex Marginean <alexandru.marginean@nxp.com>
Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
---
v2 - used readx_poll_timeout()
   - added mdio node child to the port node
   - added code comments, removed redundant err messages,
     minor code cleanup

 drivers/net/ethernet/freescale/enetc/Makefile     |   3 +-
 drivers/net/ethernet/freescale/enetc/enetc_mdio.c | 199 ++++++++++++++++++++++
 drivers/net/ethernet/freescale/enetc/enetc_pf.c   |  12 ++
 drivers/net/ethernet/freescale/enetc/enetc_pf.h   |   6 +
 4 files changed, 219 insertions(+), 1 deletion(-)
 create mode 100644 drivers/net/ethernet/freescale/enetc/enetc_mdio.c

Comments

Andrew Lunn Feb. 15, 2019, 1:34 p.m. UTC | #1 
On Fri, Feb 15, 2019 at 12:10:14PM +0200, Claudiu Manoil wrote:
> Each ENETC PF has its own MDIO interface, the corresponding
> MDIO registers are mapped in the ENETC's Port register block.
> The current patch adds a driver for these PF level MDIO buses,
> so that each PF can manage directly its own external link.
> 
> Signed-off-by: Alex Marginean <alexandru.marginean@nxp.com>
> Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
> ---
> v2 - used readx_poll_timeout()
>    - added mdio node child to the port node

Hi Claudiu

Please document this in the device tree binding.

> +	/* return all Fs if nothing was there */
> +	if (enetc_rd_reg(&regs->mdio_cfg) & MDIO_CFG_RD_ER) {
> +		dev_err(&bus->dev,
> +			"Error while reading PHY%d reg at %d.%hhu\n",
> +			phy_id, dev_addr, regnum);
> +		return 0xffff;

I'm not sure you want a dev_err() here. The device tree binding allows
you to have a phy node without a reg value. When that happens, the
core code will scan all 32 addresses to find the PHY. This is going to
spam the log. dev_dbg() might be better.

     Andrew
Claudiu Manoil Feb. 15, 2019, 2:41 p.m. UTC | #2 
>-----Original Message-----
>From: Andrew Lunn <andrew@lunn.ch>
>Sent: Friday, February 15, 2019 3:35 PM
>To: Claudiu Manoil <claudiu.manoil@nxp.com>
>Cc: Shawn Guo <shawnguo@kernel.org>; Leo Li <leoyang.li@nxp.com>; David S .
>Miller <davem@davemloft.net>; Alexandru Marginean
><alexandru.marginean@nxp.com>; linux-arm-kernel@lists.infradead.org;
>devicetree@vger.kernel.org; netdev@vger.kernel.org; linux-
>kernel@vger.kernel.org
>Subject: Re: [PATCH net-next v2 3/3] enetc: Add ENETC PF level external MDIO
>support
>
>On Fri, Feb 15, 2019 at 12:10:14PM +0200, Claudiu Manoil wrote:
>> Each ENETC PF has its own MDIO interface, the corresponding
>> MDIO registers are mapped in the ENETC's Port register block.
>> The current patch adds a driver for these PF level MDIO buses,
>> so that each PF can manage directly its own external link.
>>
>> Signed-off-by: Alex Marginean <alexandru.marginean@nxp.com>
>> Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
>> ---
>> v2 - used readx_poll_timeout()
>>    - added mdio node child to the port node
>
>Hi Claudiu
>
>Please document this in the device tree binding.
>

Hi,
I don't really see what bindings would need to be documented, as the node
names and properties used so far are common.  Like, the "mdio" node name
is common, the enetc ports are "pci" nodes, nothing special for these.
What's missing?

Regards,
Claudiu
Andrew Lunn Feb. 15, 2019, 2:56 p.m. UTC | #3 
> Hi,
> I don't really see what bindings would need to be documented, as the node
> names and properties used so far are common.  Like, the "mdio" node name
> is common, the enetc ports are "pci" nodes, nothing special for these.
> What's missing?

Hi Claudiu

It is not well defined where to put phy nodes. Some drivers do allow
them directly in the MAC node, some drivers optionally allow an mdio
sub-node, others enforce an mdio sub-node. The name of the sub-node is
also not well defined.

So just documenting that the mdio sub-node is mandatory will help
people writing device trees for their boards.

       Andrew
diff mbox series

Patch

diff --git a/drivers/net/ethernet/freescale/enetc/Makefile b/drivers/net/ethernet/freescale/enetc/Makefile
index 6976602..7139e41 100644
--- a/drivers/net/ethernet/freescale/enetc/Makefile
+++ b/drivers/net/ethernet/freescale/enetc/Makefile
@@ -1,6 +1,7 @@ 
 # SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_FSL_ENETC) += fsl-enetc.o
-fsl-enetc-$(CONFIG_FSL_ENETC) += enetc.o enetc_cbdr.o enetc_ethtool.o
+fsl-enetc-$(CONFIG_FSL_ENETC) += enetc.o enetc_cbdr.o enetc_ethtool.o \
+				 enetc_mdio.o
 fsl-enetc-$(CONFIG_PCI_IOV) += enetc_msg.o
 fsl-enetc-objs := enetc_pf.o $(fsl-enetc-y)
 
diff --git a/drivers/net/ethernet/freescale/enetc/enetc_mdio.c b/drivers/net/ethernet/freescale/enetc/enetc_mdio.c
new file mode 100644
index 0000000..f715487
--- /dev/null
+++ b/drivers/net/ethernet/freescale/enetc/enetc_mdio.c
@@ -0,0 +1,199 @@ 
+// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
+/* Copyright 2019 NXP */
+
+#include <linux/mdio.h>
+#include <linux/of_mdio.h>
+#include <linux/iopoll.h>
+#include <linux/of.h>
+
+#include "enetc_pf.h"
+
+struct enetc_mdio_regs {
+	u32	mdio_cfg;	/* MDIO configuration and status */
+	u32	mdio_ctl;	/* MDIO control */
+	u32	mdio_data;	/* MDIO data */
+	u32	mdio_addr;	/* MDIO address */
+};
+
+#define bus_to_enetc_regs(bus)	(struct enetc_mdio_regs __iomem *)((bus)->priv)
+
+#define ENETC_MDIO_REG_OFFSET	0x1c00
+#define ENETC_MDC_DIV		258
+
+#define MDIO_CFG_CLKDIV(x)	((((x) >> 1) & 0xff) << 8)
+#define MDIO_CFG_BSY		BIT(0)
+#define MDIO_CFG_RD_ER		BIT(1)
+#define MDIO_CFG_ENC45		BIT(6)
+ /* external MDIO only - driven on neg MDC edge */
+#define MDIO_CFG_NEG		BIT(23)
+
+#define MDIO_CTL_DEV_ADDR(x)	((x) & 0x1f)
+#define MDIO_CTL_PORT_ADDR(x)	(((x) & 0x1f) << 5)
+#define MDIO_CTL_READ		BIT(15)
+#define MDIO_DATA(x)		((x) & 0xffff)
+
+#define TIMEOUT	1000
+static int enetc_mdio_wait_complete(struct enetc_mdio_regs __iomem *regs)
+{
+	u32 val;
+
+	return readx_poll_timeout(enetc_rd_reg, &regs->mdio_cfg, val,
+				  !(val & MDIO_CFG_BSY), 10, 10 * TIMEOUT);
+}
+
+static int enetc_mdio_write(struct mii_bus *bus, int phy_id, int regnum,
+			    u16 value)
+{
+	struct enetc_mdio_regs __iomem *regs = bus_to_enetc_regs(bus);
+	u32 mdio_ctl, mdio_cfg;
+	u16 dev_addr;
+	int ret;
+
+	mdio_cfg = MDIO_CFG_CLKDIV(ENETC_MDC_DIV) | MDIO_CFG_NEG;
+	if (regnum & MII_ADDR_C45) {
+		dev_addr = (regnum >> 16) & 0x1f;
+		mdio_cfg |= MDIO_CFG_ENC45;
+	} else {
+		/* clause 22 (ie 1G) */
+		dev_addr = regnum & 0x1f;
+		mdio_cfg &= ~MDIO_CFG_ENC45;
+	}
+
+	enetc_wr_reg(&regs->mdio_cfg, mdio_cfg);
+
+	ret = enetc_mdio_wait_complete(regs);
+	if (ret)
+		return ret;
+
+	/* set port and dev addr */
+	mdio_ctl = MDIO_CTL_PORT_ADDR(phy_id) | MDIO_CTL_DEV_ADDR(dev_addr);
+	enetc_wr_reg(&regs->mdio_ctl, mdio_ctl);
+
+	/* set the register address */
+	if (regnum & MII_ADDR_C45) {
+		enetc_wr_reg(&regs->mdio_addr, regnum & 0xffff);
+
+		ret = enetc_mdio_wait_complete(regs);
+		if (ret)
+			return ret;
+	}
+
+	/* write the value */
+	enetc_wr_reg(&regs->mdio_data, MDIO_DATA(value));
+
+	ret = enetc_mdio_wait_complete(regs);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int enetc_mdio_read(struct mii_bus *bus, int phy_id, int regnum)
+{
+	struct enetc_mdio_regs __iomem *regs = bus_to_enetc_regs(bus);
+	u32 mdio_ctl, mdio_cfg;
+	u16 dev_addr, value;
+	int ret;
+
+	mdio_cfg = MDIO_CFG_CLKDIV(ENETC_MDC_DIV) | MDIO_CFG_NEG;
+	if (regnum & MII_ADDR_C45) {
+		dev_addr = (regnum >> 16) & 0x1f;
+		mdio_cfg |= MDIO_CFG_ENC45;
+	} else {
+		dev_addr = regnum & 0x1f;
+		mdio_cfg &= ~MDIO_CFG_ENC45;
+	}
+
+	enetc_wr_reg(&regs->mdio_cfg, mdio_cfg);
+
+	ret = enetc_mdio_wait_complete(regs);
+	if (ret)
+		return ret;
+
+	/* set port and device addr */
+	mdio_ctl = MDIO_CTL_PORT_ADDR(phy_id) | MDIO_CTL_DEV_ADDR(dev_addr);
+	enetc_wr_reg(&regs->mdio_ctl, mdio_ctl);
+
+	/* set the register address */
+	if (regnum & MII_ADDR_C45) {
+		enetc_wr_reg(&regs->mdio_addr, regnum & 0xffff);
+
+		ret = enetc_mdio_wait_complete(regs);
+		if (ret)
+			return ret;
+	}
+
+	/* initiate the read */
+	enetc_wr_reg(&regs->mdio_ctl, mdio_ctl | MDIO_CTL_READ);
+
+	ret = enetc_mdio_wait_complete(regs);
+	if (ret)
+		return ret;
+
+	/* return all Fs if nothing was there */
+	if (enetc_rd_reg(&regs->mdio_cfg) & MDIO_CFG_RD_ER) {
+		dev_err(&bus->dev,
+			"Error while reading PHY%d reg at %d.%hhu\n",
+			phy_id, dev_addr, regnum);
+		return 0xffff;
+	}
+
+	value = enetc_rd_reg(&regs->mdio_data) & 0xffff;
+
+	return value;
+}
+
+int enetc_mdio_probe(struct enetc_pf *pf)
+{
+	struct device *dev = &pf->si->pdev->dev;
+	struct enetc_mdio_regs __iomem *regs;
+	struct device_node *np;
+	struct mii_bus *bus;
+	int ret;
+
+	bus = mdiobus_alloc_size(sizeof(regs));
+	if (!bus)
+		return -ENOMEM;
+
+	bus->name = "Freescale ENETC MDIO Bus";
+	bus->read = enetc_mdio_read;
+	bus->write = enetc_mdio_write;
+	bus->parent = dev;
+	snprintf(bus->id, MII_BUS_ID_SIZE, "%s", dev_name(dev));
+
+	/* store the enetc mdio base address for this bus */
+	regs = pf->si->hw.port + ENETC_MDIO_REG_OFFSET;
+	bus->priv = regs;
+
+	np = of_get_child_by_name(dev->of_node, "mdio");
+	if (!np) {
+		dev_err(dev, "MDIO node missing\n");
+		ret = -EINVAL;
+		goto err_registration;
+	}
+
+	ret = of_mdiobus_register(bus, np);
+	if (ret) {
+		of_node_put(np);
+		dev_err(dev, "cannot register MDIO bus\n");
+		goto err_registration;
+	}
+
+	of_node_put(np);
+	pf->mdio = bus;
+
+	return 0;
+
+err_registration:
+	mdiobus_free(bus);
+
+	return ret;
+}
+
+void enetc_mdio_remove(struct enetc_pf *pf)
+{
+	if (pf->mdio) {
+		mdiobus_unregister(pf->mdio);
+		mdiobus_free(pf->mdio);
+	}
+}
diff --git a/drivers/net/ethernet/freescale/enetc/enetc_pf.c b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
index 7d28f5e..15876a6 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc_pf.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
@@ -746,6 +746,7 @@  static void enetc_pf_netdev_setup(struct enetc_si *si, struct net_device *ndev,
 
 static int enetc_of_get_phy(struct enetc_ndev_priv *priv)
 {
+	struct enetc_pf *pf = enetc_si_priv(priv->si);
 	struct device_node *np = priv->dev->of_node;
 	int err;
 
@@ -770,12 +771,22 @@  static int enetc_of_get_phy(struct enetc_ndev_priv *priv)
 		priv->phy_node = of_node_get(np);
 	}
 
+	if (!of_phy_is_fixed_link(np)) {
+		err = enetc_mdio_probe(pf);
+		if (err) {
+			of_node_put(priv->phy_node);
+			return err;
+		}
+	}
+
 	priv->if_mode = of_get_phy_mode(np);
 	if (priv->if_mode < 0) {
 		dev_err(priv->dev, "missing phy type\n");
 		of_node_put(priv->phy_node);
 		if (of_phy_is_fixed_link(np))
 			of_phy_deregister_fixed_link(np);
+		else
+			enetc_mdio_remove(pf);
 
 		return -EINVAL;
 	}
@@ -898,6 +909,7 @@  static void enetc_pf_remove(struct pci_dev *pdev)
 
 	unregister_netdev(si->ndev);
 
+	enetc_mdio_remove(pf);
 	enetc_of_put_phy(priv);
 
 	enetc_free_msix(priv);
diff --git a/drivers/net/ethernet/freescale/enetc/enetc_pf.h b/drivers/net/ethernet/freescale/enetc/enetc_pf.h
index 2061ae5..10dd1b5 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc_pf.h
+++ b/drivers/net/ethernet/freescale/enetc/enetc_pf.h
@@ -42,8 +42,14 @@  struct enetc_pf {
 	char vlan_promisc_simap; /* bitmap of SIs in VLAN promisc mode */
 	DECLARE_BITMAP(vlan_ht_filter, ENETC_VLAN_HT_SIZE);
 	DECLARE_BITMAP(active_vlans, VLAN_N_VID);
+
+	struct mii_bus *mdio; /* saved for cleanup */
 };
 
 int enetc_msg_psi_init(struct enetc_pf *pf);
 void enetc_msg_psi_free(struct enetc_pf *pf);
 void enetc_msg_handle_rxmsg(struct enetc_pf *pf, int mbox_id, u16 *status);
+
+/* MDIO */
+int enetc_mdio_probe(struct enetc_pf *pf);
+void enetc_mdio_remove(struct enetc_pf *pf);