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_mdio.h>
17 #include <linux/of_net.h>
18 #include <linux/of_platform.h>
19 #include <linux/phy.h>
20 #include <linux/prefetch.h>
21 #include <net/ip.h>
22 
xgene_mdio_rd_mac(struct xgene_mdio_pdata * pdata,u32 rd_addr)23 u32 xgene_mdio_rd_mac(struct xgene_mdio_pdata *pdata, u32 rd_addr)
24 {
25 	void __iomem *addr, *rd, *cmd, *cmd_done;
26 	u32 done, rd_data = BUSY_MASK;
27 	u8 wait = 10;
28 
29 	addr = pdata->mac_csr_addr + MAC_ADDR_REG_OFFSET;
30 	rd = pdata->mac_csr_addr + MAC_READ_REG_OFFSET;
31 	cmd = pdata->mac_csr_addr + MAC_COMMAND_REG_OFFSET;
32 	cmd_done = pdata->mac_csr_addr + MAC_COMMAND_DONE_REG_OFFSET;
33 
34 	spin_lock(&pdata->mac_lock);
35 	iowrite32(rd_addr, addr);
36 	iowrite32(XGENE_ENET_RD_CMD, cmd);
37 
38 	while (!(done = ioread32(cmd_done)) && wait--)
39 		udelay(1);
40 
41 	if (done)
42 		rd_data = ioread32(rd);
43 
44 	iowrite32(0, cmd);
45 	spin_unlock(&pdata->mac_lock);
46 
47 	return rd_data;
48 }
49 EXPORT_SYMBOL(xgene_mdio_rd_mac);
50 
xgene_mdio_wr_mac(struct xgene_mdio_pdata * pdata,u32 wr_addr,u32 data)51 void xgene_mdio_wr_mac(struct xgene_mdio_pdata *pdata, u32 wr_addr, u32 data)
52 {
53 	void __iomem *addr, *wr, *cmd, *cmd_done;
54 	u8 wait = 10;
55 	u32 done;
56 
57 	addr = pdata->mac_csr_addr + MAC_ADDR_REG_OFFSET;
58 	wr = pdata->mac_csr_addr + MAC_WRITE_REG_OFFSET;
59 	cmd = pdata->mac_csr_addr + MAC_COMMAND_REG_OFFSET;
60 	cmd_done = pdata->mac_csr_addr + MAC_COMMAND_DONE_REG_OFFSET;
61 
62 	spin_lock(&pdata->mac_lock);
63 	iowrite32(wr_addr, addr);
64 	iowrite32(data, wr);
65 	iowrite32(XGENE_ENET_WR_CMD, cmd);
66 
67 	while (!(done = ioread32(cmd_done)) && wait--)
68 		udelay(1);
69 
70 	if (!done)
71 		pr_err("MCX mac write failed, addr: 0x%04x\n", wr_addr);
72 
73 	iowrite32(0, cmd);
74 	spin_unlock(&pdata->mac_lock);
75 }
76 EXPORT_SYMBOL(xgene_mdio_wr_mac);
77 
xgene_mdio_rgmii_read(struct mii_bus * bus,int phy_id,int reg)78 int xgene_mdio_rgmii_read(struct mii_bus *bus, int phy_id, int reg)
79 {
80 	struct xgene_mdio_pdata *pdata = bus->priv;
81 	u32 data, done;
82 	u8 wait = 10;
83 
84 	data = SET_VAL(PHY_ADDR, phy_id) | SET_VAL(REG_ADDR, reg);
85 	xgene_mdio_wr_mac(pdata, MII_MGMT_ADDRESS_ADDR, data);
86 	xgene_mdio_wr_mac(pdata, MII_MGMT_COMMAND_ADDR, READ_CYCLE_MASK);
87 	do {
88 		usleep_range(5, 10);
89 		done = xgene_mdio_rd_mac(pdata, MII_MGMT_INDICATORS_ADDR);
90 	} while ((done & BUSY_MASK) && wait--);
91 
92 	if (done & BUSY_MASK) {
93 		dev_err(&bus->dev, "MII_MGMT read failed\n");
94 		return -EBUSY;
95 	}
96 
97 	data = xgene_mdio_rd_mac(pdata, MII_MGMT_STATUS_ADDR);
98 	xgene_mdio_wr_mac(pdata, MII_MGMT_COMMAND_ADDR, 0);
99 
100 	return data;
101 }
102 EXPORT_SYMBOL(xgene_mdio_rgmii_read);
103 
xgene_mdio_rgmii_write(struct mii_bus * bus,int phy_id,int reg,u16 data)104 int xgene_mdio_rgmii_write(struct mii_bus *bus, int phy_id, int reg, u16 data)
105 {
106 	struct xgene_mdio_pdata *pdata = bus->priv;
107 	u32 val, done;
108 	u8 wait = 10;
109 
110 	val = SET_VAL(PHY_ADDR, phy_id) | SET_VAL(REG_ADDR, reg);
111 	xgene_mdio_wr_mac(pdata, MII_MGMT_ADDRESS_ADDR, val);
112 
113 	xgene_mdio_wr_mac(pdata, MII_MGMT_CONTROL_ADDR, data);
114 	do {
115 		usleep_range(5, 10);
116 		done = xgene_mdio_rd_mac(pdata, MII_MGMT_INDICATORS_ADDR);
117 	} while ((done & BUSY_MASK) && wait--);
118 
119 	if (done & BUSY_MASK) {
120 		dev_err(&bus->dev, "MII_MGMT write failed\n");
121 		return -EBUSY;
122 	}
123 
124 	return 0;
125 }
126 EXPORT_SYMBOL(xgene_mdio_rgmii_write);
127 
xgene_menet_rd_diag_csr(struct xgene_mdio_pdata * pdata,u32 offset)128 static u32 xgene_menet_rd_diag_csr(struct xgene_mdio_pdata *pdata, u32 offset)
129 {
130 	return ioread32(pdata->diag_csr_addr + offset);
131 }
132 
xgene_menet_wr_diag_csr(struct xgene_mdio_pdata * pdata,u32 offset,u32 val)133 static void xgene_menet_wr_diag_csr(struct xgene_mdio_pdata *pdata,
134 				    u32 offset, u32 val)
135 {
136 	iowrite32(val, pdata->diag_csr_addr + offset);
137 }
138 
xgene_enet_ecc_init(struct xgene_mdio_pdata * pdata)139 static int xgene_enet_ecc_init(struct xgene_mdio_pdata *pdata)
140 {
141 	u32 data;
142 	u8 wait = 10;
143 
144 	xgene_menet_wr_diag_csr(pdata, MENET_CFG_MEM_RAM_SHUTDOWN_ADDR, 0x0);
145 	do {
146 		usleep_range(100, 110);
147 		data = xgene_menet_rd_diag_csr(pdata, MENET_BLOCK_MEM_RDY_ADDR);
148 	} while ((data != 0xffffffff) && wait--);
149 
150 	if (data != 0xffffffff) {
151 		dev_err(pdata->dev, "Failed to release memory from shutdown\n");
152 		return -ENODEV;
153 	}
154 
155 	return 0;
156 }
157 
xgene_gmac_reset(struct xgene_mdio_pdata * pdata)158 static void xgene_gmac_reset(struct xgene_mdio_pdata *pdata)
159 {
160 	xgene_mdio_wr_mac(pdata, MAC_CONFIG_1_ADDR, SOFT_RESET);
161 	xgene_mdio_wr_mac(pdata, MAC_CONFIG_1_ADDR, 0);
162 }
163 
xgene_mdio_reset(struct xgene_mdio_pdata * pdata)164 static int xgene_mdio_reset(struct xgene_mdio_pdata *pdata)
165 {
166 	int ret;
167 
168 	if (pdata->dev->of_node) {
169 		clk_prepare_enable(pdata->clk);
170 		udelay(5);
171 		clk_disable_unprepare(pdata->clk);
172 		udelay(5);
173 		clk_prepare_enable(pdata->clk);
174 		udelay(5);
175 	} else {
176 #ifdef CONFIG_ACPI
177 		acpi_evaluate_object(ACPI_HANDLE(pdata->dev),
178 				     "_RST", NULL, NULL);
179 #endif
180 	}
181 
182 	ret = xgene_enet_ecc_init(pdata);
183 	if (ret) {
184 		if (pdata->dev->of_node)
185 			clk_disable_unprepare(pdata->clk);
186 		return ret;
187 	}
188 	xgene_gmac_reset(pdata);
189 
190 	return 0;
191 }
192 
xgene_enet_rd_mdio_csr(void __iomem * base_addr,u32 offset,u32 * val)193 static void xgene_enet_rd_mdio_csr(void __iomem *base_addr,
194 				   u32 offset, u32 *val)
195 {
196 	void __iomem *addr = base_addr  + offset;
197 
198 	*val = ioread32(addr);
199 }
200 
xgene_enet_wr_mdio_csr(void __iomem * base_addr,u32 offset,u32 val)201 static void xgene_enet_wr_mdio_csr(void __iomem *base_addr,
202 				   u32 offset, u32 val)
203 {
204 	void __iomem *addr = base_addr  + offset;
205 
206 	iowrite32(val, addr);
207 }
208 
xgene_xfi_mdio_write(struct mii_bus * bus,int phy_id,int reg,u16 data)209 static int xgene_xfi_mdio_write(struct mii_bus *bus, int phy_id,
210 				int reg, u16 data)
211 {
212 	void __iomem *addr = (void __iomem *)bus->priv;
213 	int timeout = 100;
214 	u32 status, val;
215 
216 	val = SET_VAL(HSTPHYADX, phy_id) | SET_VAL(HSTREGADX, reg) |
217 	      SET_VAL(HSTMIIMWRDAT, data);
218 	xgene_enet_wr_mdio_csr(addr, MIIM_FIELD_ADDR, val);
219 
220 	val = HSTLDCMD | SET_VAL(HSTMIIMCMD, MIIM_CMD_LEGACY_WRITE);
221 	xgene_enet_wr_mdio_csr(addr, MIIM_COMMAND_ADDR, val);
222 
223 	do {
224 		usleep_range(5, 10);
225 		xgene_enet_rd_mdio_csr(addr, MIIM_INDICATOR_ADDR, &status);
226 	} while ((status & BUSY_MASK) && timeout--);
227 
228 	xgene_enet_wr_mdio_csr(addr, MIIM_COMMAND_ADDR, 0);
229 
230 	return 0;
231 }
232 
xgene_xfi_mdio_read(struct mii_bus * bus,int phy_id,int reg)233 static int xgene_xfi_mdio_read(struct mii_bus *bus, int phy_id, int reg)
234 {
235 	void __iomem *addr = (void __iomem *)bus->priv;
236 	u32 data, status, val;
237 	int timeout = 100;
238 
239 	val = SET_VAL(HSTPHYADX, phy_id) | SET_VAL(HSTREGADX, reg);
240 	xgene_enet_wr_mdio_csr(addr, MIIM_FIELD_ADDR, val);
241 
242 	val = HSTLDCMD | SET_VAL(HSTMIIMCMD, MIIM_CMD_LEGACY_READ);
243 	xgene_enet_wr_mdio_csr(addr, MIIM_COMMAND_ADDR, val);
244 
245 	do {
246 		usleep_range(5, 10);
247 		xgene_enet_rd_mdio_csr(addr, MIIM_INDICATOR_ADDR, &status);
248 	} while ((status & BUSY_MASK) && timeout--);
249 
250 	if (status & BUSY_MASK) {
251 		pr_err("XGENET_MII_MGMT write failed\n");
252 		return -EBUSY;
253 	}
254 
255 	xgene_enet_rd_mdio_csr(addr, MIIMRD_FIELD_ADDR, &data);
256 	xgene_enet_wr_mdio_csr(addr, MIIM_COMMAND_ADDR, 0);
257 
258 	return data;
259 }
260 
xgene_enet_phy_register(struct mii_bus * bus,int phy_addr)261 struct phy_device *xgene_enet_phy_register(struct mii_bus *bus, int phy_addr)
262 {
263 	struct phy_device *phy_dev;
264 
265 	phy_dev = get_phy_device(bus, phy_addr, false);
266 	if (!phy_dev || IS_ERR(phy_dev))
267 		return NULL;
268 
269 	if (phy_device_register(phy_dev))
270 		phy_device_free(phy_dev);
271 
272 	return phy_dev;
273 }
274 EXPORT_SYMBOL(xgene_enet_phy_register);
275 
276 #ifdef CONFIG_ACPI
acpi_register_phy(acpi_handle handle,u32 lvl,void * context,void ** ret)277 static acpi_status acpi_register_phy(acpi_handle handle, u32 lvl,
278 				     void *context, void **ret)
279 {
280 	struct mii_bus *mdio = context;
281 	struct acpi_device *adev;
282 	struct phy_device *phy_dev;
283 	const union acpi_object *obj;
284 	u32 phy_addr;
285 
286 	adev = acpi_fetch_acpi_dev(handle);
287 	if (!adev)
288 		return AE_OK;
289 
290 	if (acpi_dev_get_property(adev, "phy-channel", ACPI_TYPE_INTEGER, &obj))
291 		return AE_OK;
292 	phy_addr = obj->integer.value;
293 
294 	phy_dev = xgene_enet_phy_register(mdio, phy_addr);
295 	adev->driver_data = phy_dev;
296 
297 	return AE_OK;
298 }
299 #endif
300 
301 static const struct of_device_id xgene_mdio_of_match[] = {
302 	{
303 		.compatible = "apm,xgene-mdio-rgmii",
304 		.data = (void *)XGENE_MDIO_RGMII
305 	},
306 	{
307 		.compatible = "apm,xgene-mdio-xfi",
308 		.data = (void *)XGENE_MDIO_XFI
309 	},
310 	{},
311 };
312 MODULE_DEVICE_TABLE(of, xgene_mdio_of_match);
313 
314 #ifdef CONFIG_ACPI
315 static const struct acpi_device_id xgene_mdio_acpi_match[] = {
316 	{ "APMC0D65", XGENE_MDIO_RGMII },
317 	{ "APMC0D66", XGENE_MDIO_XFI },
318 	{ }
319 };
320 
321 MODULE_DEVICE_TABLE(acpi, xgene_mdio_acpi_match);
322 #endif
323 
324 
xgene_mdio_probe(struct platform_device * pdev)325 static int xgene_mdio_probe(struct platform_device *pdev)
326 {
327 	struct device *dev = &pdev->dev;
328 	struct mii_bus *mdio_bus;
329 	const struct of_device_id *of_id;
330 	struct xgene_mdio_pdata *pdata;
331 	void __iomem *csr_base;
332 	int mdio_id = 0, ret = 0;
333 
334 	of_id = of_match_device(xgene_mdio_of_match, &pdev->dev);
335 	if (of_id) {
336 		mdio_id = (uintptr_t)of_id->data;
337 	} else {
338 #ifdef CONFIG_ACPI
339 		const struct acpi_device_id *acpi_id;
340 
341 		acpi_id = acpi_match_device(xgene_mdio_acpi_match, &pdev->dev);
342 		if (acpi_id)
343 			mdio_id = (enum xgene_mdio_id)acpi_id->driver_data;
344 #endif
345 	}
346 
347 	if (!mdio_id)
348 		return -ENODEV;
349 
350 	pdata = devm_kzalloc(dev, sizeof(struct xgene_mdio_pdata), GFP_KERNEL);
351 	if (!pdata)
352 		return -ENOMEM;
353 	pdata->mdio_id = mdio_id;
354 	pdata->dev = dev;
355 
356 	csr_base = devm_platform_ioremap_resource(pdev, 0);
357 	if (IS_ERR(csr_base))
358 		return PTR_ERR(csr_base);
359 	pdata->mac_csr_addr = csr_base;
360 	pdata->mdio_csr_addr = csr_base + BLOCK_XG_MDIO_CSR_OFFSET;
361 	pdata->diag_csr_addr = csr_base + BLOCK_DIAG_CSR_OFFSET;
362 
363 	if (mdio_id == XGENE_MDIO_RGMII)
364 		spin_lock_init(&pdata->mac_lock);
365 
366 	if (dev->of_node) {
367 		pdata->clk = devm_clk_get(dev, NULL);
368 		if (IS_ERR(pdata->clk)) {
369 			dev_err(dev, "Unable to retrieve clk\n");
370 			return PTR_ERR(pdata->clk);
371 		}
372 	}
373 
374 	ret = xgene_mdio_reset(pdata);
375 	if (ret)
376 		return ret;
377 
378 	mdio_bus = mdiobus_alloc();
379 	if (!mdio_bus) {
380 		ret = -ENOMEM;
381 		goto out_clk;
382 	}
383 
384 	mdio_bus->name = "APM X-Gene MDIO bus";
385 
386 	if (mdio_id == XGENE_MDIO_RGMII) {
387 		mdio_bus->read = xgene_mdio_rgmii_read;
388 		mdio_bus->write = xgene_mdio_rgmii_write;
389 		mdio_bus->priv = (void __force *)pdata;
390 		snprintf(mdio_bus->id, MII_BUS_ID_SIZE, "%s",
391 			 "xgene-mii-rgmii");
392 	} else {
393 		mdio_bus->read = xgene_xfi_mdio_read;
394 		mdio_bus->write = xgene_xfi_mdio_write;
395 		mdio_bus->priv = (void __force *)pdata->mdio_csr_addr;
396 		snprintf(mdio_bus->id, MII_BUS_ID_SIZE, "%s",
397 			 "xgene-mii-xfi");
398 	}
399 
400 	mdio_bus->parent = dev;
401 	platform_set_drvdata(pdev, pdata);
402 
403 	if (dev->of_node) {
404 		ret = of_mdiobus_register(mdio_bus, dev->of_node);
405 	} else {
406 #ifdef CONFIG_ACPI
407 		/* Mask out all PHYs from auto probing. */
408 		mdio_bus->phy_mask = ~0;
409 		ret = mdiobus_register(mdio_bus);
410 		if (ret)
411 			goto out_mdiobus;
412 
413 		acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_HANDLE(dev), 1,
414 				    acpi_register_phy, NULL, mdio_bus, NULL);
415 #endif
416 	}
417 
418 	if (ret)
419 		goto out_mdiobus;
420 
421 	pdata->mdio_bus = mdio_bus;
422 
423 	return 0;
424 
425 out_mdiobus:
426 	mdiobus_free(mdio_bus);
427 
428 out_clk:
429 	if (dev->of_node)
430 		clk_disable_unprepare(pdata->clk);
431 
432 	return ret;
433 }
434 
xgene_mdio_remove(struct platform_device * pdev)435 static int xgene_mdio_remove(struct platform_device *pdev)
436 {
437 	struct xgene_mdio_pdata *pdata = platform_get_drvdata(pdev);
438 	struct mii_bus *mdio_bus = pdata->mdio_bus;
439 	struct device *dev = &pdev->dev;
440 
441 	mdiobus_unregister(mdio_bus);
442 	mdiobus_free(mdio_bus);
443 
444 	if (dev->of_node)
445 		clk_disable_unprepare(pdata->clk);
446 
447 	return 0;
448 }
449 
450 static struct platform_driver xgene_mdio_driver = {
451 	.driver = {
452 		.name = "xgene-mdio",
453 		.of_match_table = of_match_ptr(xgene_mdio_of_match),
454 		.acpi_match_table = ACPI_PTR(xgene_mdio_acpi_match),
455 	},
456 	.probe = xgene_mdio_probe,
457 	.remove = xgene_mdio_remove,
458 };
459 
460 module_platform_driver(xgene_mdio_driver);
461 
462 MODULE_DESCRIPTION("APM X-Gene SoC MDIO driver");
463 MODULE_AUTHOR("Iyappan Subramanian <isubramanian@apm.com>");
464 MODULE_LICENSE("GPL");
465