1 // SPDX-License-Identifier: GPL-2.0+
2 /* Applied Micro X-Gene SoC MDIO Driver
3  *
4  * Copyright (c) 2016, Applied Micro Circuits Corporation
5  * Author: Iyappan Subramanian <isubramanian@apm.com>
6  */
7 
8 #include <linux/acpi.h>
9 #include <linux/clk.h>
10 #include <linux/device.h>
11 #include <linux/efi.h>
12 #include <linux/if_vlan.h>
13 #include <linux/io.h>
14 #include <linux/mdio/mdio-xgene.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/of_mdio.h>
18 #include <linux/of_net.h>
19 #include <linux/phy.h>
20 #include <linux/platform_device.h>
21 #include <linux/prefetch.h>
22 #include <linux/property.h>
23 #include <net/ip.h>
24 
xgene_mdio_rd_mac(struct xgene_mdio_pdata * pdata,u32 rd_addr)25 u32 xgene_mdio_rd_mac(struct xgene_mdio_pdata *pdata, u32 rd_addr)
26 {
27 	void __iomem *addr, *rd, *cmd, *cmd_done;
28 	u32 done, rd_data = BUSY_MASK;
29 	u8 wait = 10;
30 
31 	addr = pdata->mac_csr_addr + MAC_ADDR_REG_OFFSET;
32 	rd = pdata->mac_csr_addr + MAC_READ_REG_OFFSET;
33 	cmd = pdata->mac_csr_addr + MAC_COMMAND_REG_OFFSET;
34 	cmd_done = pdata->mac_csr_addr + MAC_COMMAND_DONE_REG_OFFSET;
35 
36 	spin_lock(&pdata->mac_lock);
37 	iowrite32(rd_addr, addr);
38 	iowrite32(XGENE_ENET_RD_CMD, cmd);
39 
40 	while (!(done = ioread32(cmd_done)) && wait--)
41 		udelay(1);
42 
43 	if (done)
44 		rd_data = ioread32(rd);
45 
46 	iowrite32(0, cmd);
47 	spin_unlock(&pdata->mac_lock);
48 
49 	return rd_data;
50 }
51 EXPORT_SYMBOL(xgene_mdio_rd_mac);
52 
xgene_mdio_wr_mac(struct xgene_mdio_pdata * pdata,u32 wr_addr,u32 data)53 void xgene_mdio_wr_mac(struct xgene_mdio_pdata *pdata, u32 wr_addr, u32 data)
54 {
55 	void __iomem *addr, *wr, *cmd, *cmd_done;
56 	u8 wait = 10;
57 	u32 done;
58 
59 	addr = pdata->mac_csr_addr + MAC_ADDR_REG_OFFSET;
60 	wr = pdata->mac_csr_addr + MAC_WRITE_REG_OFFSET;
61 	cmd = pdata->mac_csr_addr + MAC_COMMAND_REG_OFFSET;
62 	cmd_done = pdata->mac_csr_addr + MAC_COMMAND_DONE_REG_OFFSET;
63 
64 	spin_lock(&pdata->mac_lock);
65 	iowrite32(wr_addr, addr);
66 	iowrite32(data, wr);
67 	iowrite32(XGENE_ENET_WR_CMD, cmd);
68 
69 	while (!(done = ioread32(cmd_done)) && wait--)
70 		udelay(1);
71 
72 	if (!done)
73 		pr_err("MCX mac write failed, addr: 0x%04x\n", wr_addr);
74 
75 	iowrite32(0, cmd);
76 	spin_unlock(&pdata->mac_lock);
77 }
78 EXPORT_SYMBOL(xgene_mdio_wr_mac);
79 
xgene_mdio_rgmii_read(struct mii_bus * bus,int phy_id,int reg)80 int xgene_mdio_rgmii_read(struct mii_bus *bus, int phy_id, int reg)
81 {
82 	struct xgene_mdio_pdata *pdata = bus->priv;
83 	u32 data, done;
84 	u8 wait = 10;
85 
86 	data = SET_VAL(PHY_ADDR, phy_id) | SET_VAL(REG_ADDR, reg);
87 	xgene_mdio_wr_mac(pdata, MII_MGMT_ADDRESS_ADDR, data);
88 	xgene_mdio_wr_mac(pdata, MII_MGMT_COMMAND_ADDR, READ_CYCLE_MASK);
89 	do {
90 		usleep_range(5, 10);
91 		done = xgene_mdio_rd_mac(pdata, MII_MGMT_INDICATORS_ADDR);
92 	} while ((done & BUSY_MASK) && wait--);
93 
94 	if (done & BUSY_MASK) {
95 		dev_err(&bus->dev, "MII_MGMT read failed\n");
96 		return -EBUSY;
97 	}
98 
99 	data = xgene_mdio_rd_mac(pdata, MII_MGMT_STATUS_ADDR);
100 	xgene_mdio_wr_mac(pdata, MII_MGMT_COMMAND_ADDR, 0);
101 
102 	return data;
103 }
104 EXPORT_SYMBOL(xgene_mdio_rgmii_read);
105 
xgene_mdio_rgmii_write(struct mii_bus * bus,int phy_id,int reg,u16 data)106 int xgene_mdio_rgmii_write(struct mii_bus *bus, int phy_id, int reg, u16 data)
107 {
108 	struct xgene_mdio_pdata *pdata = bus->priv;
109 	u32 val, done;
110 	u8 wait = 10;
111 
112 	val = SET_VAL(PHY_ADDR, phy_id) | SET_VAL(REG_ADDR, reg);
113 	xgene_mdio_wr_mac(pdata, MII_MGMT_ADDRESS_ADDR, val);
114 
115 	xgene_mdio_wr_mac(pdata, MII_MGMT_CONTROL_ADDR, data);
116 	do {
117 		usleep_range(5, 10);
118 		done = xgene_mdio_rd_mac(pdata, MII_MGMT_INDICATORS_ADDR);
119 	} while ((done & BUSY_MASK) && wait--);
120 
121 	if (done & BUSY_MASK) {
122 		dev_err(&bus->dev, "MII_MGMT write failed\n");
123 		return -EBUSY;
124 	}
125 
126 	return 0;
127 }
128 EXPORT_SYMBOL(xgene_mdio_rgmii_write);
129 
xgene_menet_rd_diag_csr(struct xgene_mdio_pdata * pdata,u32 offset)130 static u32 xgene_menet_rd_diag_csr(struct xgene_mdio_pdata *pdata, u32 offset)
131 {
132 	return ioread32(pdata->diag_csr_addr + offset);
133 }
134 
xgene_menet_wr_diag_csr(struct xgene_mdio_pdata * pdata,u32 offset,u32 val)135 static void xgene_menet_wr_diag_csr(struct xgene_mdio_pdata *pdata,
136 				    u32 offset, u32 val)
137 {
138 	iowrite32(val, pdata->diag_csr_addr + offset);
139 }
140 
xgene_enet_ecc_init(struct xgene_mdio_pdata * pdata)141 static int xgene_enet_ecc_init(struct xgene_mdio_pdata *pdata)
142 {
143 	u32 data;
144 	u8 wait = 10;
145 
146 	xgene_menet_wr_diag_csr(pdata, MENET_CFG_MEM_RAM_SHUTDOWN_ADDR, 0x0);
147 	do {
148 		usleep_range(100, 110);
149 		data = xgene_menet_rd_diag_csr(pdata, MENET_BLOCK_MEM_RDY_ADDR);
150 	} while ((data != 0xffffffff) && wait--);
151 
152 	if (data != 0xffffffff) {
153 		dev_err(pdata->dev, "Failed to release memory from shutdown\n");
154 		return -ENODEV;
155 	}
156 
157 	return 0;
158 }
159 
xgene_gmac_reset(struct xgene_mdio_pdata * pdata)160 static void xgene_gmac_reset(struct xgene_mdio_pdata *pdata)
161 {
162 	xgene_mdio_wr_mac(pdata, MAC_CONFIG_1_ADDR, SOFT_RESET);
163 	xgene_mdio_wr_mac(pdata, MAC_CONFIG_1_ADDR, 0);
164 }
165 
xgene_mdio_reset(struct xgene_mdio_pdata * pdata)166 static int xgene_mdio_reset(struct xgene_mdio_pdata *pdata)
167 {
168 	int ret;
169 
170 	if (pdata->dev->of_node) {
171 		clk_prepare_enable(pdata->clk);
172 		udelay(5);
173 		clk_disable_unprepare(pdata->clk);
174 		udelay(5);
175 		clk_prepare_enable(pdata->clk);
176 		udelay(5);
177 	} else {
178 #ifdef CONFIG_ACPI
179 		acpi_evaluate_object(ACPI_HANDLE(pdata->dev),
180 				     "_RST", NULL, NULL);
181 #endif
182 	}
183 
184 	ret = xgene_enet_ecc_init(pdata);
185 	if (ret) {
186 		if (pdata->dev->of_node)
187 			clk_disable_unprepare(pdata->clk);
188 		return ret;
189 	}
190 	xgene_gmac_reset(pdata);
191 
192 	return 0;
193 }
194 
xgene_enet_rd_mdio_csr(void __iomem * base_addr,u32 offset,u32 * val)195 static void xgene_enet_rd_mdio_csr(void __iomem *base_addr,
196 				   u32 offset, u32 *val)
197 {
198 	void __iomem *addr = base_addr  + offset;
199 
200 	*val = ioread32(addr);
201 }
202 
xgene_enet_wr_mdio_csr(void __iomem * base_addr,u32 offset,u32 val)203 static void xgene_enet_wr_mdio_csr(void __iomem *base_addr,
204 				   u32 offset, u32 val)
205 {
206 	void __iomem *addr = base_addr  + offset;
207 
208 	iowrite32(val, addr);
209 }
210 
xgene_xfi_mdio_write(struct mii_bus * bus,int phy_id,int reg,u16 data)211 static int xgene_xfi_mdio_write(struct mii_bus *bus, int phy_id,
212 				int reg, u16 data)
213 {
214 	void __iomem *addr = (void __iomem *)bus->priv;
215 	int timeout = 100;
216 	u32 status, val;
217 
218 	val = SET_VAL(HSTPHYADX, phy_id) | SET_VAL(HSTREGADX, reg) |
219 	      SET_VAL(HSTMIIMWRDAT, data);
220 	xgene_enet_wr_mdio_csr(addr, MIIM_FIELD_ADDR, val);
221 
222 	val = HSTLDCMD | SET_VAL(HSTMIIMCMD, MIIM_CMD_LEGACY_WRITE);
223 	xgene_enet_wr_mdio_csr(addr, MIIM_COMMAND_ADDR, val);
224 
225 	do {
226 		usleep_range(5, 10);
227 		xgene_enet_rd_mdio_csr(addr, MIIM_INDICATOR_ADDR, &status);
228 	} while ((status & BUSY_MASK) && timeout--);
229 
230 	xgene_enet_wr_mdio_csr(addr, MIIM_COMMAND_ADDR, 0);
231 
232 	return 0;
233 }
234 
xgene_xfi_mdio_read(struct mii_bus * bus,int phy_id,int reg)235 static int xgene_xfi_mdio_read(struct mii_bus *bus, int phy_id, int reg)
236 {
237 	void __iomem *addr = (void __iomem *)bus->priv;
238 	u32 data, status, val;
239 	int timeout = 100;
240 
241 	val = SET_VAL(HSTPHYADX, phy_id) | SET_VAL(HSTREGADX, reg);
242 	xgene_enet_wr_mdio_csr(addr, MIIM_FIELD_ADDR, val);
243 
244 	val = HSTLDCMD | SET_VAL(HSTMIIMCMD, MIIM_CMD_LEGACY_READ);
245 	xgene_enet_wr_mdio_csr(addr, MIIM_COMMAND_ADDR, val);
246 
247 	do {
248 		usleep_range(5, 10);
249 		xgene_enet_rd_mdio_csr(addr, MIIM_INDICATOR_ADDR, &status);
250 	} while ((status & BUSY_MASK) && timeout--);
251 
252 	if (status & BUSY_MASK) {
253 		pr_err("XGENET_MII_MGMT write failed\n");
254 		return -EBUSY;
255 	}
256 
257 	xgene_enet_rd_mdio_csr(addr, MIIMRD_FIELD_ADDR, &data);
258 	xgene_enet_wr_mdio_csr(addr, MIIM_COMMAND_ADDR, 0);
259 
260 	return data;
261 }
262 
xgene_enet_phy_register(struct mii_bus * bus,int phy_addr)263 struct phy_device *xgene_enet_phy_register(struct mii_bus *bus, int phy_addr)
264 {
265 	struct phy_device *phy_dev;
266 
267 	phy_dev = get_phy_device(bus, phy_addr, false);
268 	if (!phy_dev || IS_ERR(phy_dev))
269 		return NULL;
270 
271 	if (phy_device_register(phy_dev))
272 		phy_device_free(phy_dev);
273 
274 	return phy_dev;
275 }
276 EXPORT_SYMBOL(xgene_enet_phy_register);
277 
278 #ifdef CONFIG_ACPI
acpi_register_phy(acpi_handle handle,u32 lvl,void * context,void ** ret)279 static acpi_status acpi_register_phy(acpi_handle handle, u32 lvl,
280 				     void *context, void **ret)
281 {
282 	struct mii_bus *mdio = context;
283 	struct acpi_device *adev;
284 	struct phy_device *phy_dev;
285 	const union acpi_object *obj;
286 	u32 phy_addr;
287 
288 	adev = acpi_fetch_acpi_dev(handle);
289 	if (!adev)
290 		return AE_OK;
291 
292 	if (acpi_dev_get_property(adev, "phy-channel", ACPI_TYPE_INTEGER, &obj))
293 		return AE_OK;
294 	phy_addr = obj->integer.value;
295 
296 	phy_dev = xgene_enet_phy_register(mdio, phy_addr);
297 	adev->driver_data = phy_dev;
298 
299 	return AE_OK;
300 }
301 #endif
302 
303 static const struct of_device_id xgene_mdio_of_match[] = {
304 	{
305 		.compatible = "apm,xgene-mdio-rgmii",
306 		.data = (void *)XGENE_MDIO_RGMII
307 	},
308 	{
309 		.compatible = "apm,xgene-mdio-xfi",
310 		.data = (void *)XGENE_MDIO_XFI
311 	},
312 	{},
313 };
314 MODULE_DEVICE_TABLE(of, xgene_mdio_of_match);
315 
316 #ifdef CONFIG_ACPI
317 static const struct acpi_device_id xgene_mdio_acpi_match[] = {
318 	{ "APMC0D65", XGENE_MDIO_RGMII },
319 	{ "APMC0D66", XGENE_MDIO_XFI },
320 	{ }
321 };
322 
323 MODULE_DEVICE_TABLE(acpi, xgene_mdio_acpi_match);
324 #endif
325 
326 
xgene_mdio_probe(struct platform_device * pdev)327 static int xgene_mdio_probe(struct platform_device *pdev)
328 {
329 	struct device *dev = &pdev->dev;
330 	struct mii_bus *mdio_bus;
331 	struct xgene_mdio_pdata *pdata;
332 	void __iomem *csr_base;
333 	int mdio_id = 0, ret = 0;
334 
335 	mdio_id = (uintptr_t)device_get_match_data(&pdev->dev);
336 	if (!mdio_id)
337 		return -ENODEV;
338 
339 	pdata = devm_kzalloc(dev, sizeof(struct xgene_mdio_pdata), GFP_KERNEL);
340 	if (!pdata)
341 		return -ENOMEM;
342 	pdata->mdio_id = mdio_id;
343 	pdata->dev = dev;
344 
345 	csr_base = devm_platform_ioremap_resource(pdev, 0);
346 	if (IS_ERR(csr_base))
347 		return PTR_ERR(csr_base);
348 	pdata->mac_csr_addr = csr_base;
349 	pdata->mdio_csr_addr = csr_base + BLOCK_XG_MDIO_CSR_OFFSET;
350 	pdata->diag_csr_addr = csr_base + BLOCK_DIAG_CSR_OFFSET;
351 
352 	if (mdio_id == XGENE_MDIO_RGMII)
353 		spin_lock_init(&pdata->mac_lock);
354 
355 	if (dev->of_node) {
356 		pdata->clk = devm_clk_get(dev, NULL);
357 		if (IS_ERR(pdata->clk)) {
358 			dev_err(dev, "Unable to retrieve clk\n");
359 			return PTR_ERR(pdata->clk);
360 		}
361 	}
362 
363 	ret = xgene_mdio_reset(pdata);
364 	if (ret)
365 		return ret;
366 
367 	mdio_bus = mdiobus_alloc();
368 	if (!mdio_bus) {
369 		ret = -ENOMEM;
370 		goto out_clk;
371 	}
372 
373 	mdio_bus->name = "APM X-Gene MDIO bus";
374 
375 	if (mdio_id == XGENE_MDIO_RGMII) {
376 		mdio_bus->read = xgene_mdio_rgmii_read;
377 		mdio_bus->write = xgene_mdio_rgmii_write;
378 		mdio_bus->priv = (void __force *)pdata;
379 		snprintf(mdio_bus->id, MII_BUS_ID_SIZE, "%s",
380 			 "xgene-mii-rgmii");
381 	} else {
382 		mdio_bus->read = xgene_xfi_mdio_read;
383 		mdio_bus->write = xgene_xfi_mdio_write;
384 		mdio_bus->priv = (void __force *)pdata->mdio_csr_addr;
385 		snprintf(mdio_bus->id, MII_BUS_ID_SIZE, "%s",
386 			 "xgene-mii-xfi");
387 	}
388 
389 	mdio_bus->parent = dev;
390 	platform_set_drvdata(pdev, pdata);
391 
392 	if (dev->of_node) {
393 		ret = of_mdiobus_register(mdio_bus, dev->of_node);
394 	} else {
395 #ifdef CONFIG_ACPI
396 		/* Mask out all PHYs from auto probing. */
397 		mdio_bus->phy_mask = ~0;
398 		ret = mdiobus_register(mdio_bus);
399 		if (ret)
400 			goto out_mdiobus;
401 
402 		acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_HANDLE(dev), 1,
403 				    acpi_register_phy, NULL, mdio_bus, NULL);
404 #endif
405 	}
406 
407 	if (ret)
408 		goto out_mdiobus;
409 
410 	pdata->mdio_bus = mdio_bus;
411 
412 	return 0;
413 
414 out_mdiobus:
415 	mdiobus_free(mdio_bus);
416 
417 out_clk:
418 	if (dev->of_node)
419 		clk_disable_unprepare(pdata->clk);
420 
421 	return ret;
422 }
423 
xgene_mdio_remove(struct platform_device * pdev)424 static void xgene_mdio_remove(struct platform_device *pdev)
425 {
426 	struct xgene_mdio_pdata *pdata = platform_get_drvdata(pdev);
427 	struct mii_bus *mdio_bus = pdata->mdio_bus;
428 	struct device *dev = &pdev->dev;
429 
430 	mdiobus_unregister(mdio_bus);
431 	mdiobus_free(mdio_bus);
432 
433 	if (dev->of_node)
434 		clk_disable_unprepare(pdata->clk);
435 }
436 
437 static struct platform_driver xgene_mdio_driver = {
438 	.driver = {
439 		.name = "xgene-mdio",
440 		.of_match_table = xgene_mdio_of_match,
441 		.acpi_match_table = ACPI_PTR(xgene_mdio_acpi_match),
442 	},
443 	.probe = xgene_mdio_probe,
444 	.remove_new = xgene_mdio_remove,
445 };
446 
447 module_platform_driver(xgene_mdio_driver);
448 
449 MODULE_DESCRIPTION("APM X-Gene SoC MDIO driver");
450 MODULE_AUTHOR("Iyappan Subramanian <isubramanian@apm.com>");
451 MODULE_LICENSE("GPL");
452