linux/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c

472 lines
13 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*******************************************************************************
STMMAC Ethernet Driver -- MDIO bus implementation
Provides Bus interface for MII registers
Copyright (C) 2007-2009 STMicroelectronics Ltd
Author: Carl Shaw <carl.shaw@st.com>
Maintainer: Giuseppe Cavallaro <peppe.cavallaro@st.com>
*******************************************************************************/
#include <linux/gpio/consumer.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/mii.h>
#include <linux/of_mdio.h>
#include <linux/phy.h>
#include <linux/property.h>
#include <linux/slab.h>
#include "dwxgmac2.h"
#include "stmmac.h"
#define MII_BUSY 0x00000001
#define MII_WRITE 0x00000002
#define MII_DATA_MASK GENMASK(15, 0)
/* GMAC4 defines */
#define MII_GMAC4_GOC_SHIFT 2
#define MII_GMAC4_REG_ADDR_SHIFT 16
#define MII_GMAC4_WRITE (1 << MII_GMAC4_GOC_SHIFT)
#define MII_GMAC4_READ (3 << MII_GMAC4_GOC_SHIFT)
#define MII_GMAC4_C45E BIT(1)
/* XGMAC defines */
#define MII_XGMAC_SADDR BIT(18)
#define MII_XGMAC_CMD_SHIFT 16
#define MII_XGMAC_WRITE (1 << MII_XGMAC_CMD_SHIFT)
#define MII_XGMAC_READ (3 << MII_XGMAC_CMD_SHIFT)
#define MII_XGMAC_BUSY BIT(22)
#define MII_XGMAC_MAX_C22ADDR 3
#define MII_XGMAC_C22P_MASK GENMASK(MII_XGMAC_MAX_C22ADDR, 0)
#define MII_XGMAC_PA_SHIFT 16
#define MII_XGMAC_DA_SHIFT 21
static int stmmac_xgmac2_c45_format(struct stmmac_priv *priv, int phyaddr,
int phyreg, u32 *hw_addr)
{
u32 tmp;
/* Set port as Clause 45 */
tmp = readl(priv->ioaddr + XGMAC_MDIO_C22P);
tmp &= ~BIT(phyaddr);
writel(tmp, priv->ioaddr + XGMAC_MDIO_C22P);
*hw_addr = (phyaddr << MII_XGMAC_PA_SHIFT) | (phyreg & 0xffff);
*hw_addr |= (phyreg >> MII_DEVADDR_C45_SHIFT) << MII_XGMAC_DA_SHIFT;
return 0;
}
static int stmmac_xgmac2_c22_format(struct stmmac_priv *priv, int phyaddr,
int phyreg, u32 *hw_addr)
{
u32 tmp;
/* HW does not support C22 addr >= 4 */
if (phyaddr > MII_XGMAC_MAX_C22ADDR)
return -ENODEV;
/* Set port as Clause 22 */
tmp = readl(priv->ioaddr + XGMAC_MDIO_C22P);
tmp &= ~MII_XGMAC_C22P_MASK;
tmp |= BIT(phyaddr);
writel(tmp, priv->ioaddr + XGMAC_MDIO_C22P);
*hw_addr = (phyaddr << MII_XGMAC_PA_SHIFT) | (phyreg & 0x1f);
return 0;
}
static int stmmac_xgmac2_mdio_read(struct mii_bus *bus, int phyaddr, int phyreg)
{
struct net_device *ndev = bus->priv;
struct stmmac_priv *priv = netdev_priv(ndev);
unsigned int mii_address = priv->hw->mii.addr;
unsigned int mii_data = priv->hw->mii.data;
u32 tmp, addr, value = MII_XGMAC_BUSY;
int ret;
/* Wait until any existing MII operation is complete */
if (readl_poll_timeout(priv->ioaddr + mii_data, tmp,
!(tmp & MII_XGMAC_BUSY), 100, 10000))
return -EBUSY;
if (phyreg & MII_ADDR_C45) {
phyreg &= ~MII_ADDR_C45;
ret = stmmac_xgmac2_c45_format(priv, phyaddr, phyreg, &addr);
if (ret)
return ret;
} else {
ret = stmmac_xgmac2_c22_format(priv, phyaddr, phyreg, &addr);
if (ret)
return ret;
value |= MII_XGMAC_SADDR;
}
value |= (priv->clk_csr << priv->hw->mii.clk_csr_shift)
& priv->hw->mii.clk_csr_mask;
value |= MII_XGMAC_READ;
/* Wait until any existing MII operation is complete */
if (readl_poll_timeout(priv->ioaddr + mii_data, tmp,
!(tmp & MII_XGMAC_BUSY), 100, 10000))
return -EBUSY;
/* Set the MII address register to read */
writel(addr, priv->ioaddr + mii_address);
writel(value, priv->ioaddr + mii_data);
/* Wait until any existing MII operation is complete */
if (readl_poll_timeout(priv->ioaddr + mii_data, tmp,
!(tmp & MII_XGMAC_BUSY), 100, 10000))
return -EBUSY;
/* Read the data from the MII data register */
return readl(priv->ioaddr + mii_data) & GENMASK(15, 0);
}
static int stmmac_xgmac2_mdio_write(struct mii_bus *bus, int phyaddr,
int phyreg, u16 phydata)
{
struct net_device *ndev = bus->priv;
struct stmmac_priv *priv = netdev_priv(ndev);
unsigned int mii_address = priv->hw->mii.addr;
unsigned int mii_data = priv->hw->mii.data;
u32 addr, tmp, value = MII_XGMAC_BUSY;
int ret;
/* Wait until any existing MII operation is complete */
if (readl_poll_timeout(priv->ioaddr + mii_data, tmp,
!(tmp & MII_XGMAC_BUSY), 100, 10000))
return -EBUSY;
if (phyreg & MII_ADDR_C45) {
phyreg &= ~MII_ADDR_C45;
ret = stmmac_xgmac2_c45_format(priv, phyaddr, phyreg, &addr);
if (ret)
return ret;
} else {
ret = stmmac_xgmac2_c22_format(priv, phyaddr, phyreg, &addr);
if (ret)
return ret;
value |= MII_XGMAC_SADDR;
}
value |= (priv->clk_csr << priv->hw->mii.clk_csr_shift)
& priv->hw->mii.clk_csr_mask;
value |= phydata;
value |= MII_XGMAC_WRITE;
/* Wait until any existing MII operation is complete */
if (readl_poll_timeout(priv->ioaddr + mii_data, tmp,
!(tmp & MII_XGMAC_BUSY), 100, 10000))
return -EBUSY;
/* Set the MII address register to write */
writel(addr, priv->ioaddr + mii_address);
writel(value, priv->ioaddr + mii_data);
/* Wait until any existing MII operation is complete */
return readl_poll_timeout(priv->ioaddr + mii_data, tmp,
!(tmp & MII_XGMAC_BUSY), 100, 10000);
}
/**
* stmmac_mdio_read
* @bus: points to the mii_bus structure
* @phyaddr: MII addr
* @phyreg: MII reg
* Description: it reads data from the MII register from within the phy device.
* For the 7111 GMAC, we must set the bit 0 in the MII address register while
* accessing the PHY registers.
* Fortunately, it seems this has no drawback for the 7109 MAC.
*/
static int stmmac_mdio_read(struct mii_bus *bus, int phyaddr, int phyreg)
{
struct net_device *ndev = bus->priv;
struct stmmac_priv *priv = netdev_priv(ndev);
unsigned int mii_address = priv->hw->mii.addr;
unsigned int mii_data = priv->hw->mii.data;
u32 value = MII_BUSY;
int data = 0;
u32 v;
value |= (phyaddr << priv->hw->mii.addr_shift)
& priv->hw->mii.addr_mask;
value |= (phyreg << priv->hw->mii.reg_shift) & priv->hw->mii.reg_mask;
value |= (priv->clk_csr << priv->hw->mii.clk_csr_shift)
& priv->hw->mii.clk_csr_mask;
if (priv->plat->has_gmac4) {
value |= MII_GMAC4_READ;
if (phyreg & MII_ADDR_C45) {
value |= MII_GMAC4_C45E;
value &= ~priv->hw->mii.reg_mask;
value |= ((phyreg >> MII_DEVADDR_C45_SHIFT) <<
priv->hw->mii.reg_shift) &
priv->hw->mii.reg_mask;
data |= (phyreg & MII_REGADDR_C45_MASK) <<
MII_GMAC4_REG_ADDR_SHIFT;
}
}
if (readl_poll_timeout(priv->ioaddr + mii_address, v, !(v & MII_BUSY),
100, 10000))
return -EBUSY;
writel(data, priv->ioaddr + mii_data);
writel(value, priv->ioaddr + mii_address);
if (readl_poll_timeout(priv->ioaddr + mii_address, v, !(v & MII_BUSY),
100, 10000))
return -EBUSY;
/* Read the data from the MII data register */
data = (int)readl(priv->ioaddr + mii_data) & MII_DATA_MASK;
return data;
}
/**
* stmmac_mdio_write
* @bus: points to the mii_bus structure
* @phyaddr: MII addr
* @phyreg: MII reg
* @phydata: phy data
* Description: it writes the data into the MII register from within the device.
*/
static int stmmac_mdio_write(struct mii_bus *bus, int phyaddr, int phyreg,
u16 phydata)
{
struct net_device *ndev = bus->priv;
struct stmmac_priv *priv = netdev_priv(ndev);
unsigned int mii_address = priv->hw->mii.addr;
unsigned int mii_data = priv->hw->mii.data;
u32 value = MII_BUSY;
int data = phydata;
u32 v;
value |= (phyaddr << priv->hw->mii.addr_shift)
& priv->hw->mii.addr_mask;
value |= (phyreg << priv->hw->mii.reg_shift) & priv->hw->mii.reg_mask;
value |= (priv->clk_csr << priv->hw->mii.clk_csr_shift)
& priv->hw->mii.clk_csr_mask;
if (priv->plat->has_gmac4) {
value |= MII_GMAC4_WRITE;
if (phyreg & MII_ADDR_C45) {
value |= MII_GMAC4_C45E;
value &= ~priv->hw->mii.reg_mask;
value |= ((phyreg >> MII_DEVADDR_C45_SHIFT) <<
priv->hw->mii.reg_shift) &
priv->hw->mii.reg_mask;
data |= (phyreg & MII_REGADDR_C45_MASK) <<
MII_GMAC4_REG_ADDR_SHIFT;
}
} else {
value |= MII_WRITE;
}
/* Wait until any existing MII operation is complete */
if (readl_poll_timeout(priv->ioaddr + mii_address, v, !(v & MII_BUSY),
100, 10000))
return -EBUSY;
/* Set the MII address register to write */
writel(data, priv->ioaddr + mii_data);
writel(value, priv->ioaddr + mii_address);
/* Wait until any existing MII operation is complete */
return readl_poll_timeout(priv->ioaddr + mii_address, v, !(v & MII_BUSY),
100, 10000);
}
/**
* stmmac_mdio_reset
* @bus: points to the mii_bus structure
* Description: reset the MII bus
*/
int stmmac_mdio_reset(struct mii_bus *bus)
{
#if IS_ENABLED(CONFIG_STMMAC_PLATFORM)
struct net_device *ndev = bus->priv;
struct stmmac_priv *priv = netdev_priv(ndev);
unsigned int mii_address = priv->hw->mii.addr;
#ifdef CONFIG_OF
if (priv->device->of_node) {
struct gpio_desc *reset_gpio;
u32 delays[3] = { 0, 0, 0 };
reset_gpio = devm_gpiod_get_optional(priv->device,
"snps,reset",
GPIOD_OUT_LOW);
if (IS_ERR(reset_gpio))
return PTR_ERR(reset_gpio);
device_property_read_u32_array(priv->device,
"snps,reset-delays-us",
delays, ARRAY_SIZE(delays));
if (delays[0])
msleep(DIV_ROUND_UP(delays[0], 1000));
gpiod_set_value_cansleep(reset_gpio, 1);
if (delays[1])
msleep(DIV_ROUND_UP(delays[1], 1000));
gpiod_set_value_cansleep(reset_gpio, 0);
if (delays[2])
msleep(DIV_ROUND_UP(delays[2], 1000));
}
#endif
/* This is a workaround for problems with the STE101P PHY.
* It doesn't complete its reset until at least one clock cycle
* on MDC, so perform a dummy mdio read. To be updated for GMAC4
* if needed.
*/
if (!priv->plat->has_gmac4)
writel(0, priv->ioaddr + mii_address);
#endif
return 0;
}
/**
* stmmac_mdio_register
* @ndev: net device structure
* Description: it registers the MII bus
*/
int stmmac_mdio_register(struct net_device *ndev)
{
int err = 0;
struct mii_bus *new_bus;
struct stmmac_priv *priv = netdev_priv(ndev);
struct stmmac_mdio_bus_data *mdio_bus_data = priv->plat->mdio_bus_data;
struct device_node *mdio_node = priv->plat->mdio_node;
struct device *dev = ndev->dev.parent;
int addr, found, max_addr;
if (!mdio_bus_data)
return 0;
new_bus = mdiobus_alloc();
if (!new_bus)
return -ENOMEM;
if (mdio_bus_data->irqs)
memcpy(new_bus->irq, mdio_bus_data->irqs, sizeof(new_bus->irq));
new_bus->name = "stmmac";
if (priv->plat->has_xgmac) {
new_bus->read = &stmmac_xgmac2_mdio_read;
new_bus->write = &stmmac_xgmac2_mdio_write;
/* Right now only C22 phys are supported */
max_addr = MII_XGMAC_MAX_C22ADDR + 1;
/* Check if DT specified an unsupported phy addr */
if (priv->plat->phy_addr > MII_XGMAC_MAX_C22ADDR)
dev_err(dev, "Unsupported phy_addr (max=%d)\n",
MII_XGMAC_MAX_C22ADDR);
} else {
new_bus->read = &stmmac_mdio_read;
new_bus->write = &stmmac_mdio_write;
max_addr = PHY_MAX_ADDR;
}
if (mdio_bus_data->needs_reset)
new_bus->reset = &stmmac_mdio_reset;
snprintf(new_bus->id, MII_BUS_ID_SIZE, "%s-%x",
new_bus->name, priv->plat->bus_id);
new_bus->priv = ndev;
new_bus->phy_mask = mdio_bus_data->phy_mask;
new_bus->parent = priv->device;
err = of_mdiobus_register(new_bus, mdio_node);
if (err != 0) {
dev_err(dev, "Cannot register the MDIO bus\n");
goto bus_register_fail;
}
/* Looks like we need a dummy read for XGMAC only and C45 PHYs */
if (priv->plat->has_xgmac)
stmmac_xgmac2_mdio_read(new_bus, 0, MII_ADDR_C45);
if (priv->plat->phy_node || mdio_node)
goto bus_register_done;
found = 0;
for (addr = 0; addr < max_addr; addr++) {
struct phy_device *phydev = mdiobus_get_phy(new_bus, addr);
if (!phydev)
continue;
/*
* If an IRQ was provided to be assigned after
* the bus probe, do it here.
*/
if (!mdio_bus_data->irqs &&
(mdio_bus_data->probed_phy_irq > 0)) {
new_bus->irq[addr] = mdio_bus_data->probed_phy_irq;
phydev->irq = mdio_bus_data->probed_phy_irq;
}
/*
* If we're going to bind the MAC to this PHY bus,
* and no PHY number was provided to the MAC,
* use the one probed here.
*/
if (priv->plat->phy_addr == -1)
priv->plat->phy_addr = addr;
phy_attached_info(phydev);
found = 1;
}
if (!found && !mdio_node) {
dev_warn(dev, "No PHY found\n");
mdiobus_unregister(new_bus);
mdiobus_free(new_bus);
return -ENODEV;
}
bus_register_done:
priv->mii = new_bus;
return 0;
bus_register_fail:
mdiobus_free(new_bus);
return err;
}
/**
* stmmac_mdio_unregister
* @ndev: net device structure
* Description: it unregisters the MII bus
*/
int stmmac_mdio_unregister(struct net_device *ndev)
{
struct stmmac_priv *priv = netdev_priv(ndev);
if (!priv->mii)
return 0;
mdiobus_unregister(priv->mii);
priv->mii->priv = NULL;
mdiobus_free(priv->mii);
priv->mii = NULL;
return 0;
}