xref: /linux/drivers/ssb/driver_chipcommon.c (revision a671de086874b9d8155369319b2bd989cf55d77c)
1 /*
2  * Sonics Silicon Backplane
3  * Broadcom ChipCommon core driver
4  *
5  * Copyright 2005, Broadcom Corporation
6  * Copyright 2006, 2007, Michael Buesch <m@bues.ch>
7  * Copyright 2012, Hauke Mehrtens <hauke@hauke-m.de>
8  *
9  * Licensed under the GNU/GPL. See COPYING for details.
10  */
11 
12 #include <linux/ssb/ssb.h>
13 #include <linux/ssb/ssb_regs.h>
14 #include <linux/export.h>
15 #include <linux/pci.h>
16 #include <linux/bcm47xx_wdt.h>
17 
18 #include "ssb_private.h"
19 
20 
21 /* Clock sources */
22 enum ssb_clksrc {
23 	/* PCI clock */
24 	SSB_CHIPCO_CLKSRC_PCI,
25 	/* Crystal slow clock oscillator */
26 	SSB_CHIPCO_CLKSRC_XTALOS,
27 	/* Low power oscillator */
28 	SSB_CHIPCO_CLKSRC_LOPWROS,
29 };
30 
31 
32 static inline u32 chipco_write32_masked(struct ssb_chipcommon *cc, u16 offset,
33 					u32 mask, u32 value)
34 {
35 	value &= mask;
36 	value |= chipco_read32(cc, offset) & ~mask;
37 	chipco_write32(cc, offset, value);
38 
39 	return value;
40 }
41 
42 void ssb_chipco_set_clockmode(struct ssb_chipcommon *cc,
43 			      enum ssb_clkmode mode)
44 {
45 	struct ssb_device *ccdev = cc->dev;
46 	struct ssb_bus *bus;
47 	u32 tmp;
48 
49 	if (!ccdev)
50 		return;
51 	bus = ccdev->bus;
52 
53 	/* We support SLOW only on 6..9 */
54 	if (ccdev->id.revision >= 10 && mode == SSB_CLKMODE_SLOW)
55 		mode = SSB_CLKMODE_DYNAMIC;
56 
57 	if (cc->capabilities & SSB_CHIPCO_CAP_PMU)
58 		return; /* PMU controls clockmode, separated function needed */
59 	SSB_WARN_ON(ccdev->id.revision >= 20);
60 
61 	/* chipcommon cores prior to rev6 don't support dynamic clock control */
62 	if (ccdev->id.revision < 6)
63 		return;
64 
65 	/* ChipCommon cores rev10+ need testing */
66 	if (ccdev->id.revision >= 10)
67 		return;
68 
69 	if (!(cc->capabilities & SSB_CHIPCO_CAP_PCTL))
70 		return;
71 
72 	switch (mode) {
73 	case SSB_CLKMODE_SLOW: /* For revs 6..9 only */
74 		tmp = chipco_read32(cc, SSB_CHIPCO_SLOWCLKCTL);
75 		tmp |= SSB_CHIPCO_SLOWCLKCTL_FSLOW;
76 		chipco_write32(cc, SSB_CHIPCO_SLOWCLKCTL, tmp);
77 		break;
78 	case SSB_CLKMODE_FAST:
79 		if (ccdev->id.revision < 10) {
80 			ssb_pci_xtal(bus, SSB_GPIO_XTAL, 1); /* Force crystal on */
81 			tmp = chipco_read32(cc, SSB_CHIPCO_SLOWCLKCTL);
82 			tmp &= ~SSB_CHIPCO_SLOWCLKCTL_FSLOW;
83 			tmp |= SSB_CHIPCO_SLOWCLKCTL_IPLL;
84 			chipco_write32(cc, SSB_CHIPCO_SLOWCLKCTL, tmp);
85 		} else {
86 			chipco_write32(cc, SSB_CHIPCO_SYSCLKCTL,
87 				(chipco_read32(cc, SSB_CHIPCO_SYSCLKCTL) |
88 				 SSB_CHIPCO_SYSCLKCTL_FORCEHT));
89 			/* udelay(150); TODO: not available in early init */
90 		}
91 		break;
92 	case SSB_CLKMODE_DYNAMIC:
93 		if (ccdev->id.revision < 10) {
94 			tmp = chipco_read32(cc, SSB_CHIPCO_SLOWCLKCTL);
95 			tmp &= ~SSB_CHIPCO_SLOWCLKCTL_FSLOW;
96 			tmp &= ~SSB_CHIPCO_SLOWCLKCTL_IPLL;
97 			tmp &= ~SSB_CHIPCO_SLOWCLKCTL_ENXTAL;
98 			if ((tmp & SSB_CHIPCO_SLOWCLKCTL_SRC) !=
99 			    SSB_CHIPCO_SLOWCLKCTL_SRC_XTAL)
100 				tmp |= SSB_CHIPCO_SLOWCLKCTL_ENXTAL;
101 			chipco_write32(cc, SSB_CHIPCO_SLOWCLKCTL, tmp);
102 
103 			/* For dynamic control, we have to release our xtal_pu
104 			 * "force on" */
105 			if (tmp & SSB_CHIPCO_SLOWCLKCTL_ENXTAL)
106 				ssb_pci_xtal(bus, SSB_GPIO_XTAL, 0);
107 		} else {
108 			chipco_write32(cc, SSB_CHIPCO_SYSCLKCTL,
109 				(chipco_read32(cc, SSB_CHIPCO_SYSCLKCTL) &
110 				 ~SSB_CHIPCO_SYSCLKCTL_FORCEHT));
111 		}
112 		break;
113 	default:
114 		SSB_WARN_ON(1);
115 	}
116 }
117 
118 /* Get the Slow Clock Source */
119 static enum ssb_clksrc chipco_pctl_get_slowclksrc(struct ssb_chipcommon *cc)
120 {
121 	struct ssb_bus *bus = cc->dev->bus;
122 	u32 uninitialized_var(tmp);
123 
124 	if (cc->dev->id.revision < 6) {
125 		if (bus->bustype == SSB_BUSTYPE_SSB ||
126 		    bus->bustype == SSB_BUSTYPE_PCMCIA)
127 			return SSB_CHIPCO_CLKSRC_XTALOS;
128 		if (bus->bustype == SSB_BUSTYPE_PCI) {
129 			pci_read_config_dword(bus->host_pci, SSB_GPIO_OUT, &tmp);
130 			if (tmp & 0x10)
131 				return SSB_CHIPCO_CLKSRC_PCI;
132 			return SSB_CHIPCO_CLKSRC_XTALOS;
133 		}
134 	}
135 	if (cc->dev->id.revision < 10) {
136 		tmp = chipco_read32(cc, SSB_CHIPCO_SLOWCLKCTL);
137 		tmp &= 0x7;
138 		if (tmp == 0)
139 			return SSB_CHIPCO_CLKSRC_LOPWROS;
140 		if (tmp == 1)
141 			return SSB_CHIPCO_CLKSRC_XTALOS;
142 		if (tmp == 2)
143 			return SSB_CHIPCO_CLKSRC_PCI;
144 	}
145 
146 	return SSB_CHIPCO_CLKSRC_XTALOS;
147 }
148 
149 /* Get maximum or minimum (depending on get_max flag) slowclock frequency. */
150 static int chipco_pctl_clockfreqlimit(struct ssb_chipcommon *cc, int get_max)
151 {
152 	int uninitialized_var(limit);
153 	enum ssb_clksrc clocksrc;
154 	int divisor = 1;
155 	u32 tmp;
156 
157 	clocksrc = chipco_pctl_get_slowclksrc(cc);
158 	if (cc->dev->id.revision < 6) {
159 		switch (clocksrc) {
160 		case SSB_CHIPCO_CLKSRC_PCI:
161 			divisor = 64;
162 			break;
163 		case SSB_CHIPCO_CLKSRC_XTALOS:
164 			divisor = 32;
165 			break;
166 		default:
167 			SSB_WARN_ON(1);
168 		}
169 	} else if (cc->dev->id.revision < 10) {
170 		switch (clocksrc) {
171 		case SSB_CHIPCO_CLKSRC_LOPWROS:
172 			break;
173 		case SSB_CHIPCO_CLKSRC_XTALOS:
174 		case SSB_CHIPCO_CLKSRC_PCI:
175 			tmp = chipco_read32(cc, SSB_CHIPCO_SLOWCLKCTL);
176 			divisor = (tmp >> 16) + 1;
177 			divisor *= 4;
178 			break;
179 		}
180 	} else {
181 		tmp = chipco_read32(cc, SSB_CHIPCO_SYSCLKCTL);
182 		divisor = (tmp >> 16) + 1;
183 		divisor *= 4;
184 	}
185 
186 	switch (clocksrc) {
187 	case SSB_CHIPCO_CLKSRC_LOPWROS:
188 		if (get_max)
189 			limit = 43000;
190 		else
191 			limit = 25000;
192 		break;
193 	case SSB_CHIPCO_CLKSRC_XTALOS:
194 		if (get_max)
195 			limit = 20200000;
196 		else
197 			limit = 19800000;
198 		break;
199 	case SSB_CHIPCO_CLKSRC_PCI:
200 		if (get_max)
201 			limit = 34000000;
202 		else
203 			limit = 25000000;
204 		break;
205 	}
206 	limit /= divisor;
207 
208 	return limit;
209 }
210 
211 static void chipco_powercontrol_init(struct ssb_chipcommon *cc)
212 {
213 	struct ssb_bus *bus = cc->dev->bus;
214 
215 	if (bus->chip_id == 0x4321) {
216 		if (bus->chip_rev == 0)
217 			chipco_write32(cc, SSB_CHIPCO_CHIPCTL, 0x3A4);
218 		else if (bus->chip_rev == 1)
219 			chipco_write32(cc, SSB_CHIPCO_CHIPCTL, 0xA4);
220 	}
221 
222 	if (!(cc->capabilities & SSB_CHIPCO_CAP_PCTL))
223 		return;
224 
225 	if (cc->dev->id.revision >= 10) {
226 		/* Set Idle Power clock rate to 1Mhz */
227 		chipco_write32(cc, SSB_CHIPCO_SYSCLKCTL,
228 			       (chipco_read32(cc, SSB_CHIPCO_SYSCLKCTL) &
229 				0x0000FFFF) | 0x00040000);
230 	} else {
231 		int maxfreq;
232 
233 		maxfreq = chipco_pctl_clockfreqlimit(cc, 1);
234 		chipco_write32(cc, SSB_CHIPCO_PLLONDELAY,
235 			       (maxfreq * 150 + 999999) / 1000000);
236 		chipco_write32(cc, SSB_CHIPCO_FREFSELDELAY,
237 			       (maxfreq * 15 + 999999) / 1000000);
238 	}
239 }
240 
241 /* http://bcm-v4.sipsolutions.net/802.11/PmuFastPwrupDelay */
242 static u16 pmu_fast_powerup_delay(struct ssb_chipcommon *cc)
243 {
244 	struct ssb_bus *bus = cc->dev->bus;
245 
246 	switch (bus->chip_id) {
247 	case 0x4312:
248 	case 0x4322:
249 	case 0x4328:
250 		return 7000;
251 	case 0x4325:
252 		/* TODO: */
253 	default:
254 		return 15000;
255 	}
256 }
257 
258 /* http://bcm-v4.sipsolutions.net/802.11/ClkctlFastPwrupDelay */
259 static void calc_fast_powerup_delay(struct ssb_chipcommon *cc)
260 {
261 	struct ssb_bus *bus = cc->dev->bus;
262 	int minfreq;
263 	unsigned int tmp;
264 	u32 pll_on_delay;
265 
266 	if (bus->bustype != SSB_BUSTYPE_PCI)
267 		return;
268 
269 	if (cc->capabilities & SSB_CHIPCO_CAP_PMU) {
270 		cc->fast_pwrup_delay = pmu_fast_powerup_delay(cc);
271 		return;
272 	}
273 
274 	if (!(cc->capabilities & SSB_CHIPCO_CAP_PCTL))
275 		return;
276 
277 	minfreq = chipco_pctl_clockfreqlimit(cc, 0);
278 	pll_on_delay = chipco_read32(cc, SSB_CHIPCO_PLLONDELAY);
279 	tmp = (((pll_on_delay + 2) * 1000000) + (minfreq - 1)) / minfreq;
280 	SSB_WARN_ON(tmp & ~0xFFFF);
281 
282 	cc->fast_pwrup_delay = tmp;
283 }
284 
285 static u32 ssb_chipco_alp_clock(struct ssb_chipcommon *cc)
286 {
287 	if (cc->capabilities & SSB_CHIPCO_CAP_PMU)
288 		return ssb_pmu_get_alp_clock(cc);
289 
290 	return 20000000;
291 }
292 
293 static u32 ssb_chipco_watchdog_get_max_timer(struct ssb_chipcommon *cc)
294 {
295 	u32 nb;
296 
297 	if (cc->capabilities & SSB_CHIPCO_CAP_PMU) {
298 		if (cc->dev->id.revision < 26)
299 			nb = 16;
300 		else
301 			nb = (cc->dev->id.revision >= 37) ? 32 : 24;
302 	} else {
303 		nb = 28;
304 	}
305 	if (nb == 32)
306 		return 0xffffffff;
307 	else
308 		return (1 << nb) - 1;
309 }
310 
311 u32 ssb_chipco_watchdog_timer_set_wdt(struct bcm47xx_wdt *wdt, u32 ticks)
312 {
313 	struct ssb_chipcommon *cc = bcm47xx_wdt_get_drvdata(wdt);
314 
315 	if (cc->dev->bus->bustype != SSB_BUSTYPE_SSB)
316 		return 0;
317 
318 	return ssb_chipco_watchdog_timer_set(cc, ticks);
319 }
320 
321 u32 ssb_chipco_watchdog_timer_set_ms(struct bcm47xx_wdt *wdt, u32 ms)
322 {
323 	struct ssb_chipcommon *cc = bcm47xx_wdt_get_drvdata(wdt);
324 	u32 ticks;
325 
326 	if (cc->dev->bus->bustype != SSB_BUSTYPE_SSB)
327 		return 0;
328 
329 	ticks = ssb_chipco_watchdog_timer_set(cc, cc->ticks_per_ms * ms);
330 	return ticks / cc->ticks_per_ms;
331 }
332 
333 static int ssb_chipco_watchdog_ticks_per_ms(struct ssb_chipcommon *cc)
334 {
335 	struct ssb_bus *bus = cc->dev->bus;
336 
337 	if (cc->capabilities & SSB_CHIPCO_CAP_PMU) {
338 			/* based on 32KHz ILP clock */
339 			return 32;
340 	} else {
341 		if (cc->dev->id.revision < 18)
342 			return ssb_clockspeed(bus) / 1000;
343 		else
344 			return ssb_chipco_alp_clock(cc) / 1000;
345 	}
346 }
347 
348 void ssb_chipcommon_init(struct ssb_chipcommon *cc)
349 {
350 	if (!cc->dev)
351 		return; /* We don't have a ChipCommon */
352 	if (cc->dev->id.revision >= 11)
353 		cc->status = chipco_read32(cc, SSB_CHIPCO_CHIPSTAT);
354 	ssb_dprintk(KERN_INFO PFX "chipcommon status is 0x%x\n", cc->status);
355 
356 	if (cc->dev->id.revision >= 20) {
357 		chipco_write32(cc, SSB_CHIPCO_GPIOPULLUP, 0);
358 		chipco_write32(cc, SSB_CHIPCO_GPIOPULLDOWN, 0);
359 	}
360 
361 	ssb_pmu_init(cc);
362 	chipco_powercontrol_init(cc);
363 	ssb_chipco_set_clockmode(cc, SSB_CLKMODE_FAST);
364 	calc_fast_powerup_delay(cc);
365 
366 	if (cc->dev->bus->bustype == SSB_BUSTYPE_SSB) {
367 		cc->ticks_per_ms = ssb_chipco_watchdog_ticks_per_ms(cc);
368 		cc->max_timer_ms = ssb_chipco_watchdog_get_max_timer(cc) / cc->ticks_per_ms;
369 	}
370 }
371 
372 void ssb_chipco_suspend(struct ssb_chipcommon *cc)
373 {
374 	if (!cc->dev)
375 		return;
376 	ssb_chipco_set_clockmode(cc, SSB_CLKMODE_SLOW);
377 }
378 
379 void ssb_chipco_resume(struct ssb_chipcommon *cc)
380 {
381 	if (!cc->dev)
382 		return;
383 	chipco_powercontrol_init(cc);
384 	ssb_chipco_set_clockmode(cc, SSB_CLKMODE_FAST);
385 }
386 
387 /* Get the processor clock */
388 void ssb_chipco_get_clockcpu(struct ssb_chipcommon *cc,
389                              u32 *plltype, u32 *n, u32 *m)
390 {
391 	*n = chipco_read32(cc, SSB_CHIPCO_CLOCK_N);
392 	*plltype = (cc->capabilities & SSB_CHIPCO_CAP_PLLT);
393 	switch (*plltype) {
394 	case SSB_PLLTYPE_2:
395 	case SSB_PLLTYPE_4:
396 	case SSB_PLLTYPE_6:
397 	case SSB_PLLTYPE_7:
398 		*m = chipco_read32(cc, SSB_CHIPCO_CLOCK_MIPS);
399 		break;
400 	case SSB_PLLTYPE_3:
401 		/* 5350 uses m2 to control mips */
402 		*m = chipco_read32(cc, SSB_CHIPCO_CLOCK_M2);
403 		break;
404 	default:
405 		*m = chipco_read32(cc, SSB_CHIPCO_CLOCK_SB);
406 		break;
407 	}
408 }
409 
410 /* Get the bus clock */
411 void ssb_chipco_get_clockcontrol(struct ssb_chipcommon *cc,
412 				 u32 *plltype, u32 *n, u32 *m)
413 {
414 	*n = chipco_read32(cc, SSB_CHIPCO_CLOCK_N);
415 	*plltype = (cc->capabilities & SSB_CHIPCO_CAP_PLLT);
416 	switch (*plltype) {
417 	case SSB_PLLTYPE_6: /* 100/200 or 120/240 only */
418 		*m = chipco_read32(cc, SSB_CHIPCO_CLOCK_MIPS);
419 		break;
420 	case SSB_PLLTYPE_3: /* 25Mhz, 2 dividers */
421 		if (cc->dev->bus->chip_id != 0x5365) {
422 			*m = chipco_read32(cc, SSB_CHIPCO_CLOCK_M2);
423 			break;
424 		}
425 		/* Fallthough */
426 	default:
427 		*m = chipco_read32(cc, SSB_CHIPCO_CLOCK_SB);
428 	}
429 }
430 
431 void ssb_chipco_timing_init(struct ssb_chipcommon *cc,
432 			    unsigned long ns)
433 {
434 	struct ssb_device *dev = cc->dev;
435 	struct ssb_bus *bus = dev->bus;
436 	u32 tmp;
437 
438 	/* set register for external IO to control LED. */
439 	chipco_write32(cc, SSB_CHIPCO_PROG_CFG, 0x11);
440 	tmp = DIV_ROUND_UP(10, ns) << SSB_PROG_WCNT_3_SHIFT;		/* Waitcount-3 = 10ns */
441 	tmp |= DIV_ROUND_UP(40, ns) << SSB_PROG_WCNT_1_SHIFT;	/* Waitcount-1 = 40ns */
442 	tmp |= DIV_ROUND_UP(240, ns);				/* Waitcount-0 = 240ns */
443 	chipco_write32(cc, SSB_CHIPCO_PROG_WAITCNT, tmp);	/* 0x01020a0c for a 100Mhz clock */
444 
445 	/* Set timing for the flash */
446 	tmp = DIV_ROUND_UP(10, ns) << SSB_FLASH_WCNT_3_SHIFT;	/* Waitcount-3 = 10nS */
447 	tmp |= DIV_ROUND_UP(10, ns) << SSB_FLASH_WCNT_1_SHIFT;	/* Waitcount-1 = 10nS */
448 	tmp |= DIV_ROUND_UP(120, ns);				/* Waitcount-0 = 120nS */
449 	if ((bus->chip_id == 0x5365) ||
450 	    (dev->id.revision < 9))
451 		chipco_write32(cc, SSB_CHIPCO_FLASH_WAITCNT, tmp);
452 	if ((bus->chip_id == 0x5365) ||
453 	    (dev->id.revision < 9) ||
454 	    ((bus->chip_id == 0x5350) && (bus->chip_rev == 0)))
455 		chipco_write32(cc, SSB_CHIPCO_PCMCIA_MEMWAIT, tmp);
456 
457 	if (bus->chip_id == 0x5350) {
458 		/* Enable EXTIF */
459 		tmp = DIV_ROUND_UP(10, ns) << SSB_PROG_WCNT_3_SHIFT;	  /* Waitcount-3 = 10ns */
460 		tmp |= DIV_ROUND_UP(20, ns) << SSB_PROG_WCNT_2_SHIFT;  /* Waitcount-2 = 20ns */
461 		tmp |= DIV_ROUND_UP(100, ns) << SSB_PROG_WCNT_1_SHIFT; /* Waitcount-1 = 100ns */
462 		tmp |= DIV_ROUND_UP(120, ns);			  /* Waitcount-0 = 120ns */
463 		chipco_write32(cc, SSB_CHIPCO_PROG_WAITCNT, tmp); /* 0x01020a0c for a 100Mhz clock */
464 	}
465 }
466 
467 /* Set chip watchdog reset timer to fire in 'ticks' backplane cycles */
468 u32 ssb_chipco_watchdog_timer_set(struct ssb_chipcommon *cc, u32 ticks)
469 {
470 	u32 maxt;
471 	enum ssb_clkmode clkmode;
472 
473 	maxt = ssb_chipco_watchdog_get_max_timer(cc);
474 	if (cc->capabilities & SSB_CHIPCO_CAP_PMU) {
475 		if (ticks == 1)
476 			ticks = 2;
477 		else if (ticks > maxt)
478 			ticks = maxt;
479 		chipco_write32(cc, SSB_CHIPCO_PMU_WATCHDOG, ticks);
480 	} else {
481 		clkmode = ticks ? SSB_CLKMODE_FAST : SSB_CLKMODE_DYNAMIC;
482 		ssb_chipco_set_clockmode(cc, clkmode);
483 		if (ticks > maxt)
484 			ticks = maxt;
485 		/* instant NMI */
486 		chipco_write32(cc, SSB_CHIPCO_WATCHDOG, ticks);
487 	}
488 	return ticks;
489 }
490 
491 void ssb_chipco_irq_mask(struct ssb_chipcommon *cc, u32 mask, u32 value)
492 {
493 	chipco_write32_masked(cc, SSB_CHIPCO_IRQMASK, mask, value);
494 }
495 
496 u32 ssb_chipco_irq_status(struct ssb_chipcommon *cc, u32 mask)
497 {
498 	return chipco_read32(cc, SSB_CHIPCO_IRQSTAT) & mask;
499 }
500 
501 u32 ssb_chipco_gpio_in(struct ssb_chipcommon *cc, u32 mask)
502 {
503 	return chipco_read32(cc, SSB_CHIPCO_GPIOIN) & mask;
504 }
505 
506 u32 ssb_chipco_gpio_out(struct ssb_chipcommon *cc, u32 mask, u32 value)
507 {
508 	return chipco_write32_masked(cc, SSB_CHIPCO_GPIOOUT, mask, value);
509 }
510 
511 u32 ssb_chipco_gpio_outen(struct ssb_chipcommon *cc, u32 mask, u32 value)
512 {
513 	return chipco_write32_masked(cc, SSB_CHIPCO_GPIOOUTEN, mask, value);
514 }
515 
516 u32 ssb_chipco_gpio_control(struct ssb_chipcommon *cc, u32 mask, u32 value)
517 {
518 	return chipco_write32_masked(cc, SSB_CHIPCO_GPIOCTL, mask, value);
519 }
520 EXPORT_SYMBOL(ssb_chipco_gpio_control);
521 
522 u32 ssb_chipco_gpio_intmask(struct ssb_chipcommon *cc, u32 mask, u32 value)
523 {
524 	return chipco_write32_masked(cc, SSB_CHIPCO_GPIOIRQ, mask, value);
525 }
526 
527 u32 ssb_chipco_gpio_polarity(struct ssb_chipcommon *cc, u32 mask, u32 value)
528 {
529 	return chipco_write32_masked(cc, SSB_CHIPCO_GPIOPOL, mask, value);
530 }
531 
532 #ifdef CONFIG_SSB_SERIAL
533 int ssb_chipco_serial_init(struct ssb_chipcommon *cc,
534 			   struct ssb_serial_port *ports)
535 {
536 	struct ssb_bus *bus = cc->dev->bus;
537 	int nr_ports = 0;
538 	u32 plltype;
539 	unsigned int irq;
540 	u32 baud_base, div;
541 	u32 i, n;
542 	unsigned int ccrev = cc->dev->id.revision;
543 
544 	plltype = (cc->capabilities & SSB_CHIPCO_CAP_PLLT);
545 	irq = ssb_mips_irq(cc->dev);
546 
547 	if (plltype == SSB_PLLTYPE_1) {
548 		/* PLL clock */
549 		baud_base = ssb_calc_clock_rate(plltype,
550 						chipco_read32(cc, SSB_CHIPCO_CLOCK_N),
551 						chipco_read32(cc, SSB_CHIPCO_CLOCK_M2));
552 		div = 1;
553 	} else {
554 		if (ccrev == 20) {
555 			/* BCM5354 uses constant 25MHz clock */
556 			baud_base = 25000000;
557 			div = 48;
558 			/* Set the override bit so we don't divide it */
559 			chipco_write32(cc, SSB_CHIPCO_CORECTL,
560 				       chipco_read32(cc, SSB_CHIPCO_CORECTL)
561 				       | SSB_CHIPCO_CORECTL_UARTCLK0);
562 		} else if ((ccrev >= 11) && (ccrev != 15)) {
563 			baud_base = ssb_chipco_alp_clock(cc);
564 			div = 1;
565 			if (ccrev >= 21) {
566 				/* Turn off UART clock before switching clocksource. */
567 				chipco_write32(cc, SSB_CHIPCO_CORECTL,
568 					       chipco_read32(cc, SSB_CHIPCO_CORECTL)
569 					       & ~SSB_CHIPCO_CORECTL_UARTCLKEN);
570 			}
571 			/* Set the override bit so we don't divide it */
572 			chipco_write32(cc, SSB_CHIPCO_CORECTL,
573 				       chipco_read32(cc, SSB_CHIPCO_CORECTL)
574 				       | SSB_CHIPCO_CORECTL_UARTCLK0);
575 			if (ccrev >= 21) {
576 				/* Re-enable the UART clock. */
577 				chipco_write32(cc, SSB_CHIPCO_CORECTL,
578 					       chipco_read32(cc, SSB_CHIPCO_CORECTL)
579 					       | SSB_CHIPCO_CORECTL_UARTCLKEN);
580 			}
581 		} else if (ccrev >= 3) {
582 			/* Internal backplane clock */
583 			baud_base = ssb_clockspeed(bus);
584 			div = chipco_read32(cc, SSB_CHIPCO_CLKDIV)
585 			      & SSB_CHIPCO_CLKDIV_UART;
586 		} else {
587 			/* Fixed internal backplane clock */
588 			baud_base = 88000000;
589 			div = 48;
590 		}
591 
592 		/* Clock source depends on strapping if UartClkOverride is unset */
593 		if ((ccrev > 0) &&
594 		    !(chipco_read32(cc, SSB_CHIPCO_CORECTL) & SSB_CHIPCO_CORECTL_UARTCLK0)) {
595 			if ((cc->capabilities & SSB_CHIPCO_CAP_UARTCLK) ==
596 			    SSB_CHIPCO_CAP_UARTCLK_INT) {
597 				/* Internal divided backplane clock */
598 				baud_base /= div;
599 			} else {
600 				/* Assume external clock of 1.8432 MHz */
601 				baud_base = 1843200;
602 			}
603 		}
604 	}
605 
606 	/* Determine the registers of the UARTs */
607 	n = (cc->capabilities & SSB_CHIPCO_CAP_NRUART);
608 	for (i = 0; i < n; i++) {
609 		void __iomem *cc_mmio;
610 		void __iomem *uart_regs;
611 
612 		cc_mmio = cc->dev->bus->mmio + (cc->dev->core_index * SSB_CORE_SIZE);
613 		uart_regs = cc_mmio + SSB_CHIPCO_UART0_DATA;
614 		/* Offset changed at after rev 0 */
615 		if (ccrev == 0)
616 			uart_regs += (i * 8);
617 		else
618 			uart_regs += (i * 256);
619 
620 		nr_ports++;
621 		ports[i].regs = uart_regs;
622 		ports[i].irq = irq;
623 		ports[i].baud_base = baud_base;
624 		ports[i].reg_shift = 0;
625 	}
626 
627 	return nr_ports;
628 }
629 #endif /* CONFIG_SSB_SERIAL */
630