1 // SPDX-License-Identifier: GPL-2.0-only
2 /*******************************************************************************
3 STMMAC Ethernet Driver -- MDIO bus implementation
4 Provides Bus interface for MII registers
6 Copyright (C) 2007-2009 STMicroelectronics Ltd
9 Author: Carl Shaw <carl.shaw@st.com>
10 Maintainer: Giuseppe Cavallaro <peppe.cavallaro@st.com>
11 *******************************************************************************/
13 #include <linux/gpio/consumer.h>
15 #include <linux/iopoll.h>
16 #include <linux/mii.h>
17 #include <linux/of_mdio.h>
18 #include <linux/pm_runtime.h>
19 #include <linux/phy.h>
20 #include <linux/property.h>
21 #include <linux/slab.h>
26 #define MII_BUSY 0x00000001
27 #define MII_WRITE 0x00000002
28 #define MII_DATA_MASK GENMASK(15, 0)
31 #define MII_GMAC4_GOC_SHIFT 2
32 #define MII_GMAC4_REG_ADDR_SHIFT 16
33 #define MII_GMAC4_WRITE (1 << MII_GMAC4_GOC_SHIFT)
34 #define MII_GMAC4_READ (3 << MII_GMAC4_GOC_SHIFT)
35 #define MII_GMAC4_C45E BIT(1)
38 #define MII_XGMAC_SADDR BIT(18)
39 #define MII_XGMAC_CMD_SHIFT 16
40 #define MII_XGMAC_WRITE (1 << MII_XGMAC_CMD_SHIFT)
41 #define MII_XGMAC_READ (3 << MII_XGMAC_CMD_SHIFT)
42 #define MII_XGMAC_BUSY BIT(22)
43 #define MII_XGMAC_MAX_C22ADDR 3
44 #define MII_XGMAC_C22P_MASK GENMASK(MII_XGMAC_MAX_C22ADDR, 0)
45 #define MII_XGMAC_PA_SHIFT 16
46 #define MII_XGMAC_DA_SHIFT 21
48 static int stmmac_xgmac2_c45_format(struct stmmac_priv *priv, int phyaddr,
49 int phyreg, u32 *hw_addr)
53 /* Set port as Clause 45 */
54 tmp = readl(priv->ioaddr + XGMAC_MDIO_C22P);
56 writel(tmp, priv->ioaddr + XGMAC_MDIO_C22P);
58 *hw_addr = (phyaddr << MII_XGMAC_PA_SHIFT) | (phyreg & 0xffff);
59 *hw_addr |= (phyreg >> MII_DEVADDR_C45_SHIFT) << MII_XGMAC_DA_SHIFT;
63 static int stmmac_xgmac2_c22_format(struct stmmac_priv *priv, int phyaddr,
64 int phyreg, u32 *hw_addr)
68 /* HW does not support C22 addr >= 4 */
69 if (phyaddr > MII_XGMAC_MAX_C22ADDR)
72 /* Set port as Clause 22 */
73 tmp = readl(priv->ioaddr + XGMAC_MDIO_C22P);
74 tmp &= ~MII_XGMAC_C22P_MASK;
76 writel(tmp, priv->ioaddr + XGMAC_MDIO_C22P);
78 *hw_addr = (phyaddr << MII_XGMAC_PA_SHIFT) | (phyreg & 0x1f);
82 static int stmmac_xgmac2_mdio_read(struct mii_bus *bus, int phyaddr, int phyreg)
84 struct net_device *ndev = bus->priv;
85 struct stmmac_priv *priv = netdev_priv(ndev);
86 unsigned int mii_address = priv->hw->mii.addr;
87 unsigned int mii_data = priv->hw->mii.data;
88 u32 tmp, addr, value = MII_XGMAC_BUSY;
91 ret = pm_runtime_get_sync(priv->device);
93 pm_runtime_put_noidle(priv->device);
97 /* Wait until any existing MII operation is complete */
98 if (readl_poll_timeout(priv->ioaddr + mii_data, tmp,
99 !(tmp & MII_XGMAC_BUSY), 100, 10000)) {
101 goto err_disable_clks;
104 if (phyreg & MII_ADDR_C45) {
105 phyreg &= ~MII_ADDR_C45;
107 ret = stmmac_xgmac2_c45_format(priv, phyaddr, phyreg, &addr);
109 goto err_disable_clks;
111 ret = stmmac_xgmac2_c22_format(priv, phyaddr, phyreg, &addr);
113 goto err_disable_clks;
115 value |= MII_XGMAC_SADDR;
118 value |= (priv->clk_csr << priv->hw->mii.clk_csr_shift)
119 & priv->hw->mii.clk_csr_mask;
120 value |= MII_XGMAC_READ;
122 /* Wait until any existing MII operation is complete */
123 if (readl_poll_timeout(priv->ioaddr + mii_data, tmp,
124 !(tmp & MII_XGMAC_BUSY), 100, 10000)) {
126 goto err_disable_clks;
129 /* Set the MII address register to read */
130 writel(addr, priv->ioaddr + mii_address);
131 writel(value, priv->ioaddr + mii_data);
133 /* Wait until any existing MII operation is complete */
134 if (readl_poll_timeout(priv->ioaddr + mii_data, tmp,
135 !(tmp & MII_XGMAC_BUSY), 100, 10000)) {
137 goto err_disable_clks;
140 /* Read the data from the MII data register */
141 ret = (int)readl(priv->ioaddr + mii_data) & GENMASK(15, 0);
144 pm_runtime_put(priv->device);
149 static int stmmac_xgmac2_mdio_write(struct mii_bus *bus, int phyaddr,
150 int phyreg, u16 phydata)
152 struct net_device *ndev = bus->priv;
153 struct stmmac_priv *priv = netdev_priv(ndev);
154 unsigned int mii_address = priv->hw->mii.addr;
155 unsigned int mii_data = priv->hw->mii.data;
156 u32 addr, tmp, value = MII_XGMAC_BUSY;
159 ret = pm_runtime_get_sync(priv->device);
161 pm_runtime_put_noidle(priv->device);
165 /* Wait until any existing MII operation is complete */
166 if (readl_poll_timeout(priv->ioaddr + mii_data, tmp,
167 !(tmp & MII_XGMAC_BUSY), 100, 10000)) {
169 goto err_disable_clks;
172 if (phyreg & MII_ADDR_C45) {
173 phyreg &= ~MII_ADDR_C45;
175 ret = stmmac_xgmac2_c45_format(priv, phyaddr, phyreg, &addr);
177 goto err_disable_clks;
179 ret = stmmac_xgmac2_c22_format(priv, phyaddr, phyreg, &addr);
181 goto err_disable_clks;
183 value |= MII_XGMAC_SADDR;
186 value |= (priv->clk_csr << priv->hw->mii.clk_csr_shift)
187 & priv->hw->mii.clk_csr_mask;
189 value |= MII_XGMAC_WRITE;
191 /* Wait until any existing MII operation is complete */
192 if (readl_poll_timeout(priv->ioaddr + mii_data, tmp,
193 !(tmp & MII_XGMAC_BUSY), 100, 10000)) {
195 goto err_disable_clks;
198 /* Set the MII address register to write */
199 writel(addr, priv->ioaddr + mii_address);
200 writel(value, priv->ioaddr + mii_data);
202 /* Wait until any existing MII operation is complete */
203 ret = readl_poll_timeout(priv->ioaddr + mii_data, tmp,
204 !(tmp & MII_XGMAC_BUSY), 100, 10000);
207 pm_runtime_put(priv->device);
214 * @bus: points to the mii_bus structure
217 * Description: it reads data from the MII register from within the phy device.
218 * For the 7111 GMAC, we must set the bit 0 in the MII address register while
219 * accessing the PHY registers.
220 * Fortunately, it seems this has no drawback for the 7109 MAC.
222 static int stmmac_mdio_read(struct mii_bus *bus, int phyaddr, int phyreg)
224 struct net_device *ndev = bus->priv;
225 struct stmmac_priv *priv = netdev_priv(ndev);
226 unsigned int mii_address = priv->hw->mii.addr;
227 unsigned int mii_data = priv->hw->mii.data;
228 u32 value = MII_BUSY;
232 data = pm_runtime_get_sync(priv->device);
234 pm_runtime_put_noidle(priv->device);
238 value |= (phyaddr << priv->hw->mii.addr_shift)
239 & priv->hw->mii.addr_mask;
240 value |= (phyreg << priv->hw->mii.reg_shift) & priv->hw->mii.reg_mask;
241 value |= (priv->clk_csr << priv->hw->mii.clk_csr_shift)
242 & priv->hw->mii.clk_csr_mask;
243 if (priv->plat->has_gmac4) {
244 value |= MII_GMAC4_READ;
245 if (phyreg & MII_ADDR_C45) {
246 value |= MII_GMAC4_C45E;
247 value &= ~priv->hw->mii.reg_mask;
248 value |= ((phyreg >> MII_DEVADDR_C45_SHIFT) <<
249 priv->hw->mii.reg_shift) &
250 priv->hw->mii.reg_mask;
252 data |= (phyreg & MII_REGADDR_C45_MASK) <<
253 MII_GMAC4_REG_ADDR_SHIFT;
257 if (readl_poll_timeout(priv->ioaddr + mii_address, v, !(v & MII_BUSY),
260 goto err_disable_clks;
263 writel(data, priv->ioaddr + mii_data);
264 writel(value, priv->ioaddr + mii_address);
266 if (readl_poll_timeout(priv->ioaddr + mii_address, v, !(v & MII_BUSY),
269 goto err_disable_clks;
272 /* Read the data from the MII data register */
273 data = (int)readl(priv->ioaddr + mii_data) & MII_DATA_MASK;
276 pm_runtime_put(priv->device);
283 * @bus: points to the mii_bus structure
287 * Description: it writes the data into the MII register from within the device.
289 static int stmmac_mdio_write(struct mii_bus *bus, int phyaddr, int phyreg,
292 struct net_device *ndev = bus->priv;
293 struct stmmac_priv *priv = netdev_priv(ndev);
294 unsigned int mii_address = priv->hw->mii.addr;
295 unsigned int mii_data = priv->hw->mii.data;
296 int ret, data = phydata;
297 u32 value = MII_BUSY;
300 ret = pm_runtime_get_sync(priv->device);
302 pm_runtime_put_noidle(priv->device);
306 value |= (phyaddr << priv->hw->mii.addr_shift)
307 & priv->hw->mii.addr_mask;
308 value |= (phyreg << priv->hw->mii.reg_shift) & priv->hw->mii.reg_mask;
310 value |= (priv->clk_csr << priv->hw->mii.clk_csr_shift)
311 & priv->hw->mii.clk_csr_mask;
312 if (priv->plat->has_gmac4) {
313 value |= MII_GMAC4_WRITE;
314 if (phyreg & MII_ADDR_C45) {
315 value |= MII_GMAC4_C45E;
316 value &= ~priv->hw->mii.reg_mask;
317 value |= ((phyreg >> MII_DEVADDR_C45_SHIFT) <<
318 priv->hw->mii.reg_shift) &
319 priv->hw->mii.reg_mask;
321 data |= (phyreg & MII_REGADDR_C45_MASK) <<
322 MII_GMAC4_REG_ADDR_SHIFT;
328 /* Wait until any existing MII operation is complete */
329 if (readl_poll_timeout(priv->ioaddr + mii_address, v, !(v & MII_BUSY),
332 goto err_disable_clks;
335 /* Set the MII address register to write */
336 writel(data, priv->ioaddr + mii_data);
337 writel(value, priv->ioaddr + mii_address);
339 /* Wait until any existing MII operation is complete */
340 ret = readl_poll_timeout(priv->ioaddr + mii_address, v, !(v & MII_BUSY),
344 pm_runtime_put(priv->device);
351 * @bus: points to the mii_bus structure
352 * Description: reset the MII bus
354 int stmmac_mdio_reset(struct mii_bus *bus)
356 #if IS_ENABLED(CONFIG_STMMAC_PLATFORM)
357 struct net_device *ndev = bus->priv;
358 struct stmmac_priv *priv = netdev_priv(ndev);
359 unsigned int mii_address = priv->hw->mii.addr;
362 if (priv->device->of_node) {
363 struct gpio_desc *reset_gpio;
364 u32 delays[3] = { 0, 0, 0 };
366 reset_gpio = devm_gpiod_get_optional(priv->device,
369 if (IS_ERR(reset_gpio))
370 return PTR_ERR(reset_gpio);
372 device_property_read_u32_array(priv->device,
373 "snps,reset-delays-us",
374 delays, ARRAY_SIZE(delays));
377 msleep(DIV_ROUND_UP(delays[0], 1000));
379 gpiod_set_value_cansleep(reset_gpio, 1);
381 msleep(DIV_ROUND_UP(delays[1], 1000));
383 gpiod_set_value_cansleep(reset_gpio, 0);
385 msleep(DIV_ROUND_UP(delays[2], 1000));
389 /* This is a workaround for problems with the STE101P PHY.
390 * It doesn't complete its reset until at least one clock cycle
391 * on MDC, so perform a dummy mdio read. To be updated for GMAC4
394 if (!priv->plat->has_gmac4)
395 writel(0, priv->ioaddr + mii_address);
401 * stmmac_mdio_register
402 * @ndev: net device structure
403 * Description: it registers the MII bus
405 int stmmac_mdio_register(struct net_device *ndev)
408 struct mii_bus *new_bus;
409 struct stmmac_priv *priv = netdev_priv(ndev);
410 struct stmmac_mdio_bus_data *mdio_bus_data = priv->plat->mdio_bus_data;
411 struct device_node *mdio_node = priv->plat->mdio_node;
412 struct device *dev = ndev->dev.parent;
413 int addr, found, max_addr;
418 new_bus = mdiobus_alloc();
422 if (mdio_bus_data->irqs)
423 memcpy(new_bus->irq, mdio_bus_data->irqs, sizeof(new_bus->irq));
425 new_bus->name = "stmmac";
427 if (priv->plat->has_xgmac) {
428 new_bus->read = &stmmac_xgmac2_mdio_read;
429 new_bus->write = &stmmac_xgmac2_mdio_write;
431 /* Right now only C22 phys are supported */
432 max_addr = MII_XGMAC_MAX_C22ADDR + 1;
434 /* Check if DT specified an unsupported phy addr */
435 if (priv->plat->phy_addr > MII_XGMAC_MAX_C22ADDR)
436 dev_err(dev, "Unsupported phy_addr (max=%d)\n",
437 MII_XGMAC_MAX_C22ADDR);
439 new_bus->read = &stmmac_mdio_read;
440 new_bus->write = &stmmac_mdio_write;
441 max_addr = PHY_MAX_ADDR;
444 if (mdio_bus_data->has_xpcs) {
445 priv->hw->xpcs = mdio_xpcs_get_ops();
446 if (!priv->hw->xpcs) {
448 goto bus_register_fail;
452 if (mdio_bus_data->needs_reset)
453 new_bus->reset = &stmmac_mdio_reset;
455 snprintf(new_bus->id, MII_BUS_ID_SIZE, "%s-%x",
456 new_bus->name, priv->plat->bus_id);
457 new_bus->priv = ndev;
458 new_bus->phy_mask = mdio_bus_data->phy_mask;
459 new_bus->parent = priv->device;
461 err = of_mdiobus_register(new_bus, mdio_node);
462 if (err == -ENODEV) {
464 dev_info(dev, "MDIO bus is disabled\n");
465 goto bus_register_fail;
467 dev_err_probe(dev, err, "Cannot register the MDIO bus\n");
468 goto bus_register_fail;
471 /* Looks like we need a dummy read for XGMAC only and C45 PHYs */
472 if (priv->plat->has_xgmac)
473 stmmac_xgmac2_mdio_read(new_bus, 0, MII_ADDR_C45);
475 if (priv->plat->phy_node || mdio_node)
476 goto bus_register_done;
479 for (addr = 0; addr < max_addr; addr++) {
480 struct phy_device *phydev = mdiobus_get_phy(new_bus, addr);
486 * If an IRQ was provided to be assigned after
487 * the bus probe, do it here.
489 if (!mdio_bus_data->irqs &&
490 (mdio_bus_data->probed_phy_irq > 0)) {
491 new_bus->irq[addr] = mdio_bus_data->probed_phy_irq;
492 phydev->irq = mdio_bus_data->probed_phy_irq;
496 * If we're going to bind the MAC to this PHY bus,
497 * and no PHY number was provided to the MAC,
498 * use the one probed here.
500 if (priv->plat->phy_addr == -1)
501 priv->plat->phy_addr = addr;
503 phy_attached_info(phydev);
507 if (!found && !mdio_node) {
508 dev_warn(dev, "No PHY found\n");
513 /* Try to probe the XPCS by scanning all addresses. */
514 if (priv->hw->xpcs) {
515 struct mdio_xpcs_args *xpcs = &priv->hw->xpcs_args;
516 int ret, mode = priv->plat->phy_interface;
517 max_addr = PHY_MAX_ADDR;
522 for (addr = 0; addr < max_addr; addr++) {
525 ret = stmmac_xpcs_probe(priv, xpcs, mode);
532 if (!found && !mdio_node) {
533 dev_warn(dev, "No XPCS found\n");
546 mdiobus_unregister(new_bus);
548 mdiobus_free(new_bus);
553 * stmmac_mdio_unregister
554 * @ndev: net device structure
555 * Description: it unregisters the MII bus
557 int stmmac_mdio_unregister(struct net_device *ndev)
559 struct stmmac_priv *priv = netdev_priv(ndev);
564 mdiobus_unregister(priv->mii);
565 priv->mii->priv = NULL;
566 mdiobus_free(priv->mii);