1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Freescale PowerQUICC Ethernet Driver -- MIIM bus implementation
4 * Provides Bus interface for MIIM regs
5 *
6 * Author: Andy Fleming <afleming@freescale.com>
7 * Modifier: Sandeep Gopalpet <sandeep.kumar@freescale.com>
8 *
9 * Copyright 2002-2004, 2008-2009 Freescale Semiconductor, Inc.
10 *
11 * Based on gianfar_mii.c and ucc_geth_mii.c (Li Yang, Kim Phillips)
12 */
13
14 #include <linux/kernel.h>
15 #include <linux/platform_device.h>
16 #include <linux/string.h>
17 #include <linux/errno.h>
18 #include <linux/slab.h>
19 #include <linux/delay.h>
20 #include <linux/module.h>
21 #include <linux/mii.h>
22 #include <linux/of.h>
23 #include <linux/of_address.h>
24 #include <linux/of_mdio.h>
25 #include <linux/property.h>
26
27 #include <asm/io.h>
28 #if IS_ENABLED(CONFIG_UCC_GETH)
29 #include <soc/fsl/qe/ucc.h>
30 #endif
31
32 #include "gianfar.h"
33
34 #define MIIMIND_BUSY 0x00000001
35 #define MIIMIND_NOTVALID 0x00000004
36 #define MIIMCFG_INIT_VALUE 0x00000007
37 #define MIIMCFG_RESET 0x80000000
38
39 #define MII_READ_COMMAND 0x00000001
40
41 struct fsl_pq_mii {
42 u32 miimcfg; /* MII management configuration reg */
43 u32 miimcom; /* MII management command reg */
44 u32 miimadd; /* MII management address reg */
45 u32 miimcon; /* MII management control reg */
46 u32 miimstat; /* MII management status reg */
47 u32 miimind; /* MII management indication reg */
48 };
49
50 struct fsl_pq_mdio {
51 u8 res1[16];
52 u32 ieventm; /* MDIO Interrupt event register (for etsec2)*/
53 u32 imaskm; /* MDIO Interrupt mask register (for etsec2)*/
54 u8 res2[4];
55 u32 emapm; /* MDIO Event mapping register (for etsec2)*/
56 u8 res3[1280];
57 struct fsl_pq_mii mii;
58 u8 res4[28];
59 u32 utbipar; /* TBI phy address reg (only on UCC) */
60 u8 res5[2728];
61 } __packed;
62
63 /* Number of microseconds to wait for an MII register to respond */
64 #define MII_TIMEOUT 1000
65
66 struct fsl_pq_mdio_priv {
67 void __iomem *map;
68 struct fsl_pq_mii __iomem *regs;
69 };
70
71 /*
72 * Per-device-type data. Each type of device tree node that we support gets
73 * one of these.
74 *
75 * @mii_offset: the offset of the MII registers within the memory map of the
76 * node. Some nodes define only the MII registers, and some define the whole
77 * MAC (which includes the MII registers).
78 *
79 * @get_tbipa: determines the address of the TBIPA register
80 *
81 * @ucc_configure: a special function for extra QE configuration
82 */
83 struct fsl_pq_mdio_data {
84 unsigned int mii_offset; /* offset of the MII registers */
85 uint32_t __iomem * (*get_tbipa)(void __iomem *p);
86 void (*ucc_configure)(phys_addr_t start, phys_addr_t end);
87 };
88
89 /*
90 * Write value to the PHY at mii_id at register regnum, on the bus attached
91 * to the local interface, which may be different from the generic mdio bus
92 * (tied to a single interface), waiting until the write is done before
93 * returning. This is helpful in programming interfaces like the TBI which
94 * control interfaces like onchip SERDES and are always tied to the local
95 * mdio pins, which may not be the same as system mdio bus, used for
96 * controlling the external PHYs, for example.
97 */
fsl_pq_mdio_write(struct mii_bus * bus,int mii_id,int regnum,u16 value)98 static int fsl_pq_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
99 u16 value)
100 {
101 struct fsl_pq_mdio_priv *priv = bus->priv;
102 struct fsl_pq_mii __iomem *regs = priv->regs;
103 unsigned int timeout;
104
105 /* Set the PHY address and the register address we want to write */
106 iowrite32be((mii_id << 8) | regnum, ®s->miimadd);
107
108 /* Write out the value we want */
109 iowrite32be(value, ®s->miimcon);
110
111 /* Wait for the transaction to finish */
112 timeout = MII_TIMEOUT;
113 while ((ioread32be(®s->miimind) & MIIMIND_BUSY) && timeout) {
114 cpu_relax();
115 timeout--;
116 }
117
118 return timeout ? 0 : -ETIMEDOUT;
119 }
120
121 /*
122 * Read the bus for PHY at addr mii_id, register regnum, and return the value.
123 * Clears miimcom first.
124 *
125 * All PHY operation done on the bus attached to the local interface, which
126 * may be different from the generic mdio bus. This is helpful in programming
127 * interfaces like the TBI which, in turn, control interfaces like on-chip
128 * SERDES and are always tied to the local mdio pins, which may not be the
129 * same as system mdio bus, used for controlling the external PHYs, for eg.
130 */
fsl_pq_mdio_read(struct mii_bus * bus,int mii_id,int regnum)131 static int fsl_pq_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
132 {
133 struct fsl_pq_mdio_priv *priv = bus->priv;
134 struct fsl_pq_mii __iomem *regs = priv->regs;
135 unsigned int timeout;
136 u16 value;
137
138 /* Set the PHY address and the register address we want to read */
139 iowrite32be((mii_id << 8) | regnum, ®s->miimadd);
140
141 /* Clear miimcom, and then initiate a read */
142 iowrite32be(0, ®s->miimcom);
143 iowrite32be(MII_READ_COMMAND, ®s->miimcom);
144
145 /* Wait for the transaction to finish, normally less than 100us */
146 timeout = MII_TIMEOUT;
147 while ((ioread32be(®s->miimind) &
148 (MIIMIND_NOTVALID | MIIMIND_BUSY)) && timeout) {
149 cpu_relax();
150 timeout--;
151 }
152
153 if (!timeout)
154 return -ETIMEDOUT;
155
156 /* Grab the value of the register from miimstat */
157 value = ioread32be(®s->miimstat);
158
159 dev_dbg(&bus->dev, "read %04x from address %x/%x\n", value, mii_id, regnum);
160 return value;
161 }
162
163 /* Reset the MIIM registers, and wait for the bus to free */
fsl_pq_mdio_reset(struct mii_bus * bus)164 static int fsl_pq_mdio_reset(struct mii_bus *bus)
165 {
166 struct fsl_pq_mdio_priv *priv = bus->priv;
167 struct fsl_pq_mii __iomem *regs = priv->regs;
168 unsigned int timeout;
169
170 mutex_lock(&bus->mdio_lock);
171
172 /* Reset the management interface */
173 iowrite32be(MIIMCFG_RESET, ®s->miimcfg);
174
175 /* Setup the MII Mgmt clock speed */
176 iowrite32be(MIIMCFG_INIT_VALUE, ®s->miimcfg);
177
178 /* Wait until the bus is free */
179 timeout = MII_TIMEOUT;
180 while ((ioread32be(®s->miimind) & MIIMIND_BUSY) && timeout) {
181 cpu_relax();
182 timeout--;
183 }
184
185 mutex_unlock(&bus->mdio_lock);
186
187 if (!timeout) {
188 dev_err(&bus->dev, "timeout waiting for MII bus\n");
189 return -EBUSY;
190 }
191
192 return 0;
193 }
194
195 #if IS_ENABLED(CONFIG_GIANFAR)
196 /*
197 * Return the TBIPA address, starting from the address
198 * of the mapped GFAR MDIO registers (struct gfar)
199 * This is mildly evil, but so is our hardware for doing this.
200 * Also, we have to cast back to struct gfar because of
201 * definition weirdness done in gianfar.h.
202 */
get_gfar_tbipa_from_mdio(void __iomem * p)203 static uint32_t __iomem *get_gfar_tbipa_from_mdio(void __iomem *p)
204 {
205 struct gfar __iomem *enet_regs = p;
206
207 return &enet_regs->tbipa;
208 }
209
210 /*
211 * Return the TBIPA address, starting from the address
212 * of the mapped GFAR MII registers (gfar_mii_regs[] within struct gfar)
213 */
get_gfar_tbipa_from_mii(void __iomem * p)214 static uint32_t __iomem *get_gfar_tbipa_from_mii(void __iomem *p)
215 {
216 return get_gfar_tbipa_from_mdio(container_of(p, struct gfar, gfar_mii_regs));
217 }
218
219 /*
220 * Return the TBIPAR address for an eTSEC2 node
221 */
get_etsec_tbipa(void __iomem * p)222 static uint32_t __iomem *get_etsec_tbipa(void __iomem *p)
223 {
224 return p;
225 }
226 #endif
227
228 #if IS_ENABLED(CONFIG_UCC_GETH)
229 /*
230 * Return the TBIPAR address for a QE MDIO node, starting from the address
231 * of the mapped MII registers (struct fsl_pq_mii)
232 */
get_ucc_tbipa(void __iomem * p)233 static uint32_t __iomem *get_ucc_tbipa(void __iomem *p)
234 {
235 struct fsl_pq_mdio __iomem *mdio = container_of(p, struct fsl_pq_mdio, mii);
236
237 return &mdio->utbipar;
238 }
239
240 /*
241 * Find the UCC node that controls the given MDIO node
242 *
243 * For some reason, the QE MDIO nodes are not children of the UCC devices
244 * that control them. Therefore, we need to scan all UCC nodes looking for
245 * the one that encompases the given MDIO node. We do this by comparing
246 * physical addresses. The 'start' and 'end' addresses of the MDIO node are
247 * passed, and the correct UCC node will cover the entire address range.
248 *
249 * This assumes that there is only one QE MDIO node in the entire device tree.
250 */
ucc_configure(phys_addr_t start,phys_addr_t end)251 static void ucc_configure(phys_addr_t start, phys_addr_t end)
252 {
253 static bool found_mii_master;
254 struct device_node *np = NULL;
255
256 if (found_mii_master)
257 return;
258
259 for_each_compatible_node(np, NULL, "ucc_geth") {
260 struct resource res;
261 const uint32_t *iprop;
262 uint32_t id;
263 int ret;
264
265 ret = of_address_to_resource(np, 0, &res);
266 if (ret < 0) {
267 pr_debug("fsl-pq-mdio: no address range in node %pOF\n",
268 np);
269 continue;
270 }
271
272 /* if our mdio regs fall within this UCC regs range */
273 if ((start < res.start) || (end > res.end))
274 continue;
275
276 iprop = of_get_property(np, "cell-index", NULL);
277 if (!iprop) {
278 iprop = of_get_property(np, "device-id", NULL);
279 if (!iprop) {
280 pr_debug("fsl-pq-mdio: no UCC ID in node %pOF\n",
281 np);
282 continue;
283 }
284 }
285
286 id = be32_to_cpup(iprop);
287
288 /*
289 * cell-index and device-id for QE nodes are
290 * numbered from 1, not 0.
291 */
292 if (ucc_set_qe_mux_mii_mng(id - 1) < 0) {
293 pr_debug("fsl-pq-mdio: invalid UCC ID in node %pOF\n",
294 np);
295 continue;
296 }
297
298 pr_debug("fsl-pq-mdio: setting node UCC%u to MII master\n", id);
299 found_mii_master = true;
300 }
301 }
302
303 #endif
304
305 static const struct of_device_id fsl_pq_mdio_match[] = {
306 #if IS_ENABLED(CONFIG_GIANFAR)
307 {
308 .compatible = "fsl,gianfar-tbi",
309 .data = &(struct fsl_pq_mdio_data) {
310 .mii_offset = 0,
311 .get_tbipa = get_gfar_tbipa_from_mii,
312 },
313 },
314 {
315 .compatible = "fsl,gianfar-mdio",
316 .data = &(struct fsl_pq_mdio_data) {
317 .mii_offset = 0,
318 .get_tbipa = get_gfar_tbipa_from_mii,
319 },
320 },
321 {
322 .type = "mdio",
323 .compatible = "gianfar",
324 .data = &(struct fsl_pq_mdio_data) {
325 .mii_offset = offsetof(struct fsl_pq_mdio, mii),
326 .get_tbipa = get_gfar_tbipa_from_mdio,
327 },
328 },
329 {
330 .compatible = "fsl,etsec2-tbi",
331 .data = &(struct fsl_pq_mdio_data) {
332 .mii_offset = offsetof(struct fsl_pq_mdio, mii),
333 .get_tbipa = get_etsec_tbipa,
334 },
335 },
336 {
337 .compatible = "fsl,etsec2-mdio",
338 .data = &(struct fsl_pq_mdio_data) {
339 .mii_offset = offsetof(struct fsl_pq_mdio, mii),
340 .get_tbipa = get_etsec_tbipa,
341 },
342 },
343 #endif
344 #if IS_ENABLED(CONFIG_UCC_GETH)
345 {
346 .compatible = "fsl,ucc-mdio",
347 .data = &(struct fsl_pq_mdio_data) {
348 .mii_offset = 0,
349 .get_tbipa = get_ucc_tbipa,
350 .ucc_configure = ucc_configure,
351 },
352 },
353 {
354 /* Legacy UCC MDIO node */
355 .type = "mdio",
356 .compatible = "ucc_geth_phy",
357 .data = &(struct fsl_pq_mdio_data) {
358 .mii_offset = 0,
359 .get_tbipa = get_ucc_tbipa,
360 .ucc_configure = ucc_configure,
361 },
362 },
363 #endif
364 /* No Kconfig option for Fman support yet */
365 {
366 .compatible = "fsl,fman-mdio",
367 .data = &(struct fsl_pq_mdio_data) {
368 .mii_offset = 0,
369 /* Fman TBI operations are handled elsewhere */
370 },
371 },
372
373 {},
374 };
375 MODULE_DEVICE_TABLE(of, fsl_pq_mdio_match);
376
set_tbipa(const u32 tbipa_val,struct platform_device * pdev,uint32_t __iomem * (* get_tbipa)(void __iomem *),void __iomem * reg_map,struct resource * reg_res)377 static void set_tbipa(const u32 tbipa_val, struct platform_device *pdev,
378 uint32_t __iomem * (*get_tbipa)(void __iomem *),
379 void __iomem *reg_map, struct resource *reg_res)
380 {
381 struct device_node *np = pdev->dev.of_node;
382 uint32_t __iomem *tbipa;
383 bool tbipa_mapped;
384
385 tbipa = of_iomap(np, 1);
386 if (tbipa) {
387 tbipa_mapped = true;
388 } else {
389 tbipa_mapped = false;
390 tbipa = (*get_tbipa)(reg_map);
391
392 /*
393 * Add consistency check to make sure TBI is contained within
394 * the mapped range (not because we would get a segfault,
395 * rather to catch bugs in computing TBI address). Print error
396 * message but continue anyway.
397 */
398 if ((void *)tbipa > reg_map + resource_size(reg_res) - 4)
399 dev_err(&pdev->dev, "invalid register map (should be at least 0x%04zx to contain TBI address)\n",
400 ((void *)tbipa - reg_map) + 4);
401 }
402
403 iowrite32be(be32_to_cpu(tbipa_val), tbipa);
404
405 if (tbipa_mapped)
406 iounmap(tbipa);
407 }
408
fsl_pq_mdio_probe(struct platform_device * pdev)409 static int fsl_pq_mdio_probe(struct platform_device *pdev)
410 {
411 const struct fsl_pq_mdio_data *data;
412 struct device_node *np = pdev->dev.of_node;
413 struct resource res;
414 struct device_node *tbi;
415 struct fsl_pq_mdio_priv *priv;
416 struct mii_bus *new_bus;
417 int err;
418
419 data = device_get_match_data(&pdev->dev);
420 if (!data) {
421 dev_err(&pdev->dev, "Failed to match device\n");
422 return -ENODEV;
423 }
424
425 new_bus = mdiobus_alloc_size(sizeof(*priv));
426 if (!new_bus)
427 return -ENOMEM;
428
429 priv = new_bus->priv;
430 new_bus->name = "Freescale PowerQUICC MII Bus";
431 new_bus->read = &fsl_pq_mdio_read;
432 new_bus->write = &fsl_pq_mdio_write;
433 new_bus->reset = &fsl_pq_mdio_reset;
434
435 err = of_address_to_resource(np, 0, &res);
436 if (err < 0) {
437 dev_err(&pdev->dev, "could not obtain address information\n");
438 goto error;
439 }
440
441 snprintf(new_bus->id, MII_BUS_ID_SIZE, "%pOFn@%llx", np,
442 (unsigned long long)res.start);
443
444 priv->map = of_iomap(np, 0);
445 if (!priv->map) {
446 err = -ENOMEM;
447 goto error;
448 }
449
450 /*
451 * Some device tree nodes represent only the MII registers, and
452 * others represent the MAC and MII registers. The 'mii_offset' field
453 * contains the offset of the MII registers inside the mapped register
454 * space.
455 */
456 if (data->mii_offset > resource_size(&res)) {
457 dev_err(&pdev->dev, "invalid register map\n");
458 err = -EINVAL;
459 goto error;
460 }
461 priv->regs = priv->map + data->mii_offset;
462
463 new_bus->parent = &pdev->dev;
464 platform_set_drvdata(pdev, new_bus);
465
466 if (data->get_tbipa) {
467 for_each_child_of_node(np, tbi) {
468 if (of_node_is_type(tbi, "tbi-phy")) {
469 dev_dbg(&pdev->dev, "found TBI PHY node %pOFP\n",
470 tbi);
471 break;
472 }
473 }
474
475 if (tbi) {
476 const u32 *prop = of_get_property(tbi, "reg", NULL);
477 if (!prop) {
478 dev_err(&pdev->dev,
479 "missing 'reg' property in node %pOF\n",
480 tbi);
481 err = -EBUSY;
482 goto error;
483 }
484 set_tbipa(*prop, pdev,
485 data->get_tbipa, priv->map, &res);
486 }
487 }
488
489 if (data->ucc_configure)
490 data->ucc_configure(res.start, res.end);
491
492 err = of_mdiobus_register(new_bus, np);
493 if (err) {
494 dev_err(&pdev->dev, "cannot register %s as MDIO bus\n",
495 new_bus->name);
496 goto error;
497 }
498
499 return 0;
500
501 error:
502 if (priv->map)
503 iounmap(priv->map);
504
505 kfree(new_bus);
506
507 return err;
508 }
509
510
fsl_pq_mdio_remove(struct platform_device * pdev)511 static void fsl_pq_mdio_remove(struct platform_device *pdev)
512 {
513 struct device *device = &pdev->dev;
514 struct mii_bus *bus = dev_get_drvdata(device);
515 struct fsl_pq_mdio_priv *priv = bus->priv;
516
517 mdiobus_unregister(bus);
518
519 iounmap(priv->map);
520 mdiobus_free(bus);
521 }
522
523 static struct platform_driver fsl_pq_mdio_driver = {
524 .driver = {
525 .name = "fsl-pq_mdio",
526 .of_match_table = fsl_pq_mdio_match,
527 },
528 .probe = fsl_pq_mdio_probe,
529 .remove_new = fsl_pq_mdio_remove,
530 };
531
532 module_platform_driver(fsl_pq_mdio_driver);
533
534 MODULE_DESCRIPTION("Freescale PQ MDIO helpers");
535 MODULE_LICENSE("GPL");
536