xref: /linux/drivers/usb/host/pci-quirks.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
1 /*
2  * This file contains code to reset and initialize USB host controllers.
3  * Some of it includes work-arounds for PCI hardware and BIOS quirks.
4  * It may need to run early during booting -- before USB would normally
5  * initialize -- to ensure that Linux doesn't use any legacy modes.
6  *
7  *  Copyright (c) 1999 Martin Mares <mj@ucw.cz>
8  *  (and others)
9  */
10 
11 #include <linux/types.h>
12 #include <linux/kernel.h>
13 #include <linux/pci.h>
14 #include <linux/init.h>
15 #include <linux/delay.h>
16 #include <linux/export.h>
17 #include <linux/acpi.h>
18 #include <linux/dmi.h>
19 #include "pci-quirks.h"
20 #include "xhci-ext-caps.h"
21 
22 
23 #define UHCI_USBLEGSUP		0xc0		/* legacy support */
24 #define UHCI_USBCMD		0		/* command register */
25 #define UHCI_USBINTR		4		/* interrupt register */
26 #define UHCI_USBLEGSUP_RWC	0x8f00		/* the R/WC bits */
27 #define UHCI_USBLEGSUP_RO	0x5040		/* R/O and reserved bits */
28 #define UHCI_USBCMD_RUN		0x0001		/* RUN/STOP bit */
29 #define UHCI_USBCMD_HCRESET	0x0002		/* Host Controller reset */
30 #define UHCI_USBCMD_EGSM	0x0008		/* Global Suspend Mode */
31 #define UHCI_USBCMD_CONFIGURE	0x0040		/* Config Flag */
32 #define UHCI_USBINTR_RESUME	0x0002		/* Resume interrupt enable */
33 
34 #define OHCI_CONTROL		0x04
35 #define OHCI_CMDSTATUS		0x08
36 #define OHCI_INTRSTATUS		0x0c
37 #define OHCI_INTRENABLE		0x10
38 #define OHCI_INTRDISABLE	0x14
39 #define OHCI_FMINTERVAL		0x34
40 #define OHCI_HCR		(1 << 0)	/* host controller reset */
41 #define OHCI_OCR		(1 << 3)	/* ownership change request */
42 #define OHCI_CTRL_RWC		(1 << 9)	/* remote wakeup connected */
43 #define OHCI_CTRL_IR		(1 << 8)	/* interrupt routing */
44 #define OHCI_INTR_OC		(1 << 30)	/* ownership change */
45 
46 #define EHCI_HCC_PARAMS		0x08		/* extended capabilities */
47 #define EHCI_USBCMD		0		/* command register */
48 #define EHCI_USBCMD_RUN		(1 << 0)	/* RUN/STOP bit */
49 #define EHCI_USBSTS		4		/* status register */
50 #define EHCI_USBSTS_HALTED	(1 << 12)	/* HCHalted bit */
51 #define EHCI_USBINTR		8		/* interrupt register */
52 #define EHCI_CONFIGFLAG		0x40		/* configured flag register */
53 #define EHCI_USBLEGSUP		0		/* legacy support register */
54 #define EHCI_USBLEGSUP_BIOS	(1 << 16)	/* BIOS semaphore */
55 #define EHCI_USBLEGSUP_OS	(1 << 24)	/* OS semaphore */
56 #define EHCI_USBLEGCTLSTS	4		/* legacy control/status */
57 #define EHCI_USBLEGCTLSTS_SOOE	(1 << 13)	/* SMI on ownership change */
58 
59 /* AMD quirk use */
60 #define	AB_REG_BAR_LOW		0xe0
61 #define	AB_REG_BAR_HIGH		0xe1
62 #define	AB_REG_BAR_SB700	0xf0
63 #define	AB_INDX(addr)		((addr) + 0x00)
64 #define	AB_DATA(addr)		((addr) + 0x04)
65 #define	AX_INDXC		0x30
66 #define	AX_DATAC		0x34
67 
68 #define	NB_PCIE_INDX_ADDR	0xe0
69 #define	NB_PCIE_INDX_DATA	0xe4
70 #define	PCIE_P_CNTL		0x10040
71 #define	BIF_NB			0x10002
72 #define	NB_PIF0_PWRDOWN_0	0x01100012
73 #define	NB_PIF0_PWRDOWN_1	0x01100013
74 
75 #define USB_INTEL_XUSB2PR      0xD0
76 #define USB_INTEL_USB3_PSSEN   0xD8
77 
78 static struct amd_chipset_info {
79 	struct pci_dev	*nb_dev;
80 	struct pci_dev	*smbus_dev;
81 	int nb_type;
82 	int sb_type;
83 	int isoc_reqs;
84 	int probe_count;
85 	int probe_result;
86 } amd_chipset;
87 
88 static DEFINE_SPINLOCK(amd_lock);
89 
90 int usb_amd_find_chipset_info(void)
91 {
92 	u8 rev = 0;
93 	unsigned long flags;
94 	struct amd_chipset_info info;
95 	int ret;
96 
97 	spin_lock_irqsave(&amd_lock, flags);
98 
99 	/* probe only once */
100 	if (amd_chipset.probe_count > 0) {
101 		amd_chipset.probe_count++;
102 		spin_unlock_irqrestore(&amd_lock, flags);
103 		return amd_chipset.probe_result;
104 	}
105 	memset(&info, 0, sizeof(info));
106 	spin_unlock_irqrestore(&amd_lock, flags);
107 
108 	info.smbus_dev = pci_get_device(PCI_VENDOR_ID_ATI, 0x4385, NULL);
109 	if (info.smbus_dev) {
110 		rev = info.smbus_dev->revision;
111 		if (rev >= 0x40)
112 			info.sb_type = 1;
113 		else if (rev >= 0x30 && rev <= 0x3b)
114 			info.sb_type = 3;
115 	} else {
116 		info.smbus_dev = pci_get_device(PCI_VENDOR_ID_AMD,
117 						0x780b, NULL);
118 		if (!info.smbus_dev) {
119 			ret = 0;
120 			goto commit;
121 		}
122 
123 		rev = info.smbus_dev->revision;
124 		if (rev >= 0x11 && rev <= 0x18)
125 			info.sb_type = 2;
126 	}
127 
128 	if (info.sb_type == 0) {
129 		if (info.smbus_dev) {
130 			pci_dev_put(info.smbus_dev);
131 			info.smbus_dev = NULL;
132 		}
133 		ret = 0;
134 		goto commit;
135 	}
136 
137 	info.nb_dev = pci_get_device(PCI_VENDOR_ID_AMD, 0x9601, NULL);
138 	if (info.nb_dev) {
139 		info.nb_type = 1;
140 	} else {
141 		info.nb_dev = pci_get_device(PCI_VENDOR_ID_AMD, 0x1510, NULL);
142 		if (info.nb_dev) {
143 			info.nb_type = 2;
144 		} else {
145 			info.nb_dev = pci_get_device(PCI_VENDOR_ID_AMD,
146 						     0x9600, NULL);
147 			if (info.nb_dev)
148 				info.nb_type = 3;
149 		}
150 	}
151 
152 	ret = info.probe_result = 1;
153 	printk(KERN_DEBUG "QUIRK: Enable AMD PLL fix\n");
154 
155 commit:
156 
157 	spin_lock_irqsave(&amd_lock, flags);
158 	if (amd_chipset.probe_count > 0) {
159 		/* race - someone else was faster - drop devices */
160 
161 		/* Mark that we where here */
162 		amd_chipset.probe_count++;
163 		ret = amd_chipset.probe_result;
164 
165 		spin_unlock_irqrestore(&amd_lock, flags);
166 
167 		if (info.nb_dev)
168 			pci_dev_put(info.nb_dev);
169 		if (info.smbus_dev)
170 			pci_dev_put(info.smbus_dev);
171 
172 	} else {
173 		/* no race - commit the result */
174 		info.probe_count++;
175 		amd_chipset = info;
176 		spin_unlock_irqrestore(&amd_lock, flags);
177 	}
178 
179 	return ret;
180 }
181 EXPORT_SYMBOL_GPL(usb_amd_find_chipset_info);
182 
183 /*
184  * The hardware normally enables the A-link power management feature, which
185  * lets the system lower the power consumption in idle states.
186  *
187  * This USB quirk prevents the link going into that lower power state
188  * during isochronous transfers.
189  *
190  * Without this quirk, isochronous stream on OHCI/EHCI/xHCI controllers of
191  * some AMD platforms may stutter or have breaks occasionally.
192  */
193 static void usb_amd_quirk_pll(int disable)
194 {
195 	u32 addr, addr_low, addr_high, val;
196 	u32 bit = disable ? 0 : 1;
197 	unsigned long flags;
198 
199 	spin_lock_irqsave(&amd_lock, flags);
200 
201 	if (disable) {
202 		amd_chipset.isoc_reqs++;
203 		if (amd_chipset.isoc_reqs > 1) {
204 			spin_unlock_irqrestore(&amd_lock, flags);
205 			return;
206 		}
207 	} else {
208 		amd_chipset.isoc_reqs--;
209 		if (amd_chipset.isoc_reqs > 0) {
210 			spin_unlock_irqrestore(&amd_lock, flags);
211 			return;
212 		}
213 	}
214 
215 	if (amd_chipset.sb_type == 1 || amd_chipset.sb_type == 2) {
216 		outb_p(AB_REG_BAR_LOW, 0xcd6);
217 		addr_low = inb_p(0xcd7);
218 		outb_p(AB_REG_BAR_HIGH, 0xcd6);
219 		addr_high = inb_p(0xcd7);
220 		addr = addr_high << 8 | addr_low;
221 
222 		outl_p(0x30, AB_INDX(addr));
223 		outl_p(0x40, AB_DATA(addr));
224 		outl_p(0x34, AB_INDX(addr));
225 		val = inl_p(AB_DATA(addr));
226 	} else if (amd_chipset.sb_type == 3) {
227 		pci_read_config_dword(amd_chipset.smbus_dev,
228 					AB_REG_BAR_SB700, &addr);
229 		outl(AX_INDXC, AB_INDX(addr));
230 		outl(0x40, AB_DATA(addr));
231 		outl(AX_DATAC, AB_INDX(addr));
232 		val = inl(AB_DATA(addr));
233 	} else {
234 		spin_unlock_irqrestore(&amd_lock, flags);
235 		return;
236 	}
237 
238 	if (disable) {
239 		val &= ~0x08;
240 		val |= (1 << 4) | (1 << 9);
241 	} else {
242 		val |= 0x08;
243 		val &= ~((1 << 4) | (1 << 9));
244 	}
245 	outl_p(val, AB_DATA(addr));
246 
247 	if (!amd_chipset.nb_dev) {
248 		spin_unlock_irqrestore(&amd_lock, flags);
249 		return;
250 	}
251 
252 	if (amd_chipset.nb_type == 1 || amd_chipset.nb_type == 3) {
253 		addr = PCIE_P_CNTL;
254 		pci_write_config_dword(amd_chipset.nb_dev,
255 					NB_PCIE_INDX_ADDR, addr);
256 		pci_read_config_dword(amd_chipset.nb_dev,
257 					NB_PCIE_INDX_DATA, &val);
258 
259 		val &= ~(1 | (1 << 3) | (1 << 4) | (1 << 9) | (1 << 12));
260 		val |= bit | (bit << 3) | (bit << 12);
261 		val |= ((!bit) << 4) | ((!bit) << 9);
262 		pci_write_config_dword(amd_chipset.nb_dev,
263 					NB_PCIE_INDX_DATA, val);
264 
265 		addr = BIF_NB;
266 		pci_write_config_dword(amd_chipset.nb_dev,
267 					NB_PCIE_INDX_ADDR, addr);
268 		pci_read_config_dword(amd_chipset.nb_dev,
269 					NB_PCIE_INDX_DATA, &val);
270 		val &= ~(1 << 8);
271 		val |= bit << 8;
272 
273 		pci_write_config_dword(amd_chipset.nb_dev,
274 					NB_PCIE_INDX_DATA, val);
275 	} else if (amd_chipset.nb_type == 2) {
276 		addr = NB_PIF0_PWRDOWN_0;
277 		pci_write_config_dword(amd_chipset.nb_dev,
278 					NB_PCIE_INDX_ADDR, addr);
279 		pci_read_config_dword(amd_chipset.nb_dev,
280 					NB_PCIE_INDX_DATA, &val);
281 		if (disable)
282 			val &= ~(0x3f << 7);
283 		else
284 			val |= 0x3f << 7;
285 
286 		pci_write_config_dword(amd_chipset.nb_dev,
287 					NB_PCIE_INDX_DATA, val);
288 
289 		addr = NB_PIF0_PWRDOWN_1;
290 		pci_write_config_dword(amd_chipset.nb_dev,
291 					NB_PCIE_INDX_ADDR, addr);
292 		pci_read_config_dword(amd_chipset.nb_dev,
293 					NB_PCIE_INDX_DATA, &val);
294 		if (disable)
295 			val &= ~(0x3f << 7);
296 		else
297 			val |= 0x3f << 7;
298 
299 		pci_write_config_dword(amd_chipset.nb_dev,
300 					NB_PCIE_INDX_DATA, val);
301 	}
302 
303 	spin_unlock_irqrestore(&amd_lock, flags);
304 	return;
305 }
306 
307 void usb_amd_quirk_pll_disable(void)
308 {
309 	usb_amd_quirk_pll(1);
310 }
311 EXPORT_SYMBOL_GPL(usb_amd_quirk_pll_disable);
312 
313 void usb_amd_quirk_pll_enable(void)
314 {
315 	usb_amd_quirk_pll(0);
316 }
317 EXPORT_SYMBOL_GPL(usb_amd_quirk_pll_enable);
318 
319 void usb_amd_dev_put(void)
320 {
321 	struct pci_dev *nb, *smbus;
322 	unsigned long flags;
323 
324 	spin_lock_irqsave(&amd_lock, flags);
325 
326 	amd_chipset.probe_count--;
327 	if (amd_chipset.probe_count > 0) {
328 		spin_unlock_irqrestore(&amd_lock, flags);
329 		return;
330 	}
331 
332 	/* save them to pci_dev_put outside of spinlock */
333 	nb    = amd_chipset.nb_dev;
334 	smbus = amd_chipset.smbus_dev;
335 
336 	amd_chipset.nb_dev = NULL;
337 	amd_chipset.smbus_dev = NULL;
338 	amd_chipset.nb_type = 0;
339 	amd_chipset.sb_type = 0;
340 	amd_chipset.isoc_reqs = 0;
341 	amd_chipset.probe_result = 0;
342 
343 	spin_unlock_irqrestore(&amd_lock, flags);
344 
345 	if (nb)
346 		pci_dev_put(nb);
347 	if (smbus)
348 		pci_dev_put(smbus);
349 }
350 EXPORT_SYMBOL_GPL(usb_amd_dev_put);
351 
352 /*
353  * Make sure the controller is completely inactive, unable to
354  * generate interrupts or do DMA.
355  */
356 void uhci_reset_hc(struct pci_dev *pdev, unsigned long base)
357 {
358 	/* Turn off PIRQ enable and SMI enable.  (This also turns off the
359 	 * BIOS's USB Legacy Support.)  Turn off all the R/WC bits too.
360 	 */
361 	pci_write_config_word(pdev, UHCI_USBLEGSUP, UHCI_USBLEGSUP_RWC);
362 
363 	/* Reset the HC - this will force us to get a
364 	 * new notification of any already connected
365 	 * ports due to the virtual disconnect that it
366 	 * implies.
367 	 */
368 	outw(UHCI_USBCMD_HCRESET, base + UHCI_USBCMD);
369 	mb();
370 	udelay(5);
371 	if (inw(base + UHCI_USBCMD) & UHCI_USBCMD_HCRESET)
372 		dev_warn(&pdev->dev, "HCRESET not completed yet!\n");
373 
374 	/* Just to be safe, disable interrupt requests and
375 	 * make sure the controller is stopped.
376 	 */
377 	outw(0, base + UHCI_USBINTR);
378 	outw(0, base + UHCI_USBCMD);
379 }
380 EXPORT_SYMBOL_GPL(uhci_reset_hc);
381 
382 /*
383  * Initialize a controller that was newly discovered or has just been
384  * resumed.  In either case we can't be sure of its previous state.
385  *
386  * Returns: 1 if the controller was reset, 0 otherwise.
387  */
388 int uhci_check_and_reset_hc(struct pci_dev *pdev, unsigned long base)
389 {
390 	u16 legsup;
391 	unsigned int cmd, intr;
392 
393 	/*
394 	 * When restarting a suspended controller, we expect all the
395 	 * settings to be the same as we left them:
396 	 *
397 	 *	PIRQ and SMI disabled, no R/W bits set in USBLEGSUP;
398 	 *	Controller is stopped and configured with EGSM set;
399 	 *	No interrupts enabled except possibly Resume Detect.
400 	 *
401 	 * If any of these conditions are violated we do a complete reset.
402 	 */
403 	pci_read_config_word(pdev, UHCI_USBLEGSUP, &legsup);
404 	if (legsup & ~(UHCI_USBLEGSUP_RO | UHCI_USBLEGSUP_RWC)) {
405 		dev_dbg(&pdev->dev, "%s: legsup = 0x%04x\n",
406 				__func__, legsup);
407 		goto reset_needed;
408 	}
409 
410 	cmd = inw(base + UHCI_USBCMD);
411 	if ((cmd & UHCI_USBCMD_RUN) || !(cmd & UHCI_USBCMD_CONFIGURE) ||
412 			!(cmd & UHCI_USBCMD_EGSM)) {
413 		dev_dbg(&pdev->dev, "%s: cmd = 0x%04x\n",
414 				__func__, cmd);
415 		goto reset_needed;
416 	}
417 
418 	intr = inw(base + UHCI_USBINTR);
419 	if (intr & (~UHCI_USBINTR_RESUME)) {
420 		dev_dbg(&pdev->dev, "%s: intr = 0x%04x\n",
421 				__func__, intr);
422 		goto reset_needed;
423 	}
424 	return 0;
425 
426 reset_needed:
427 	dev_dbg(&pdev->dev, "Performing full reset\n");
428 	uhci_reset_hc(pdev, base);
429 	return 1;
430 }
431 EXPORT_SYMBOL_GPL(uhci_check_and_reset_hc);
432 
433 static inline int io_type_enabled(struct pci_dev *pdev, unsigned int mask)
434 {
435 	u16 cmd;
436 	return !pci_read_config_word(pdev, PCI_COMMAND, &cmd) && (cmd & mask);
437 }
438 
439 #define pio_enabled(dev) io_type_enabled(dev, PCI_COMMAND_IO)
440 #define mmio_enabled(dev) io_type_enabled(dev, PCI_COMMAND_MEMORY)
441 
442 static void __devinit quirk_usb_handoff_uhci(struct pci_dev *pdev)
443 {
444 	unsigned long base = 0;
445 	int i;
446 
447 	if (!pio_enabled(pdev))
448 		return;
449 
450 	for (i = 0; i < PCI_ROM_RESOURCE; i++)
451 		if ((pci_resource_flags(pdev, i) & IORESOURCE_IO)) {
452 			base = pci_resource_start(pdev, i);
453 			break;
454 		}
455 
456 	if (base)
457 		uhci_check_and_reset_hc(pdev, base);
458 }
459 
460 static int __devinit mmio_resource_enabled(struct pci_dev *pdev, int idx)
461 {
462 	return pci_resource_start(pdev, idx) && mmio_enabled(pdev);
463 }
464 
465 static void __devinit quirk_usb_handoff_ohci(struct pci_dev *pdev)
466 {
467 	void __iomem *base;
468 	u32 control;
469 
470 	if (!mmio_resource_enabled(pdev, 0))
471 		return;
472 
473 	base = pci_ioremap_bar(pdev, 0);
474 	if (base == NULL)
475 		return;
476 
477 	control = readl(base + OHCI_CONTROL);
478 
479 /* On PA-RISC, PDC can leave IR set incorrectly; ignore it there. */
480 #ifdef __hppa__
481 #define	OHCI_CTRL_MASK		(OHCI_CTRL_RWC | OHCI_CTRL_IR)
482 #else
483 #define	OHCI_CTRL_MASK		OHCI_CTRL_RWC
484 
485 	if (control & OHCI_CTRL_IR) {
486 		int wait_time = 500; /* arbitrary; 5 seconds */
487 		writel(OHCI_INTR_OC, base + OHCI_INTRENABLE);
488 		writel(OHCI_OCR, base + OHCI_CMDSTATUS);
489 		while (wait_time > 0 &&
490 				readl(base + OHCI_CONTROL) & OHCI_CTRL_IR) {
491 			wait_time -= 10;
492 			msleep(10);
493 		}
494 		if (wait_time <= 0)
495 			dev_warn(&pdev->dev, "OHCI: BIOS handoff failed"
496 					" (BIOS bug?) %08x\n",
497 					readl(base + OHCI_CONTROL));
498 	}
499 #endif
500 
501 	/* reset controller, preserving RWC (and possibly IR) */
502 	writel(control & OHCI_CTRL_MASK, base + OHCI_CONTROL);
503 	readl(base + OHCI_CONTROL);
504 
505 	/* Some NVIDIA controllers stop working if kept in RESET for too long */
506 	if (pdev->vendor == PCI_VENDOR_ID_NVIDIA) {
507 		u32 fminterval;
508 		int cnt;
509 
510 		/* drive reset for at least 50 ms (7.1.7.5) */
511 		msleep(50);
512 
513 		/* software reset of the controller, preserving HcFmInterval */
514 		fminterval = readl(base + OHCI_FMINTERVAL);
515 		writel(OHCI_HCR, base + OHCI_CMDSTATUS);
516 
517 		/* reset requires max 10 us delay */
518 		for (cnt = 30; cnt > 0; --cnt) {	/* ... allow extra time */
519 			if ((readl(base + OHCI_CMDSTATUS) & OHCI_HCR) == 0)
520 				break;
521 			udelay(1);
522 		}
523 		writel(fminterval, base + OHCI_FMINTERVAL);
524 
525 		/* Now we're in the SUSPEND state with all devices reset
526 		 * and wakeups and interrupts disabled
527 		 */
528 	}
529 
530 	/*
531 	 * disable interrupts
532 	 */
533 	writel(~(u32)0, base + OHCI_INTRDISABLE);
534 	writel(~(u32)0, base + OHCI_INTRSTATUS);
535 
536 	iounmap(base);
537 }
538 
539 static const struct dmi_system_id __devinitconst ehci_dmi_nohandoff_table[] = {
540 	{
541 		/*  Pegatron Lucid (ExoPC) */
542 		.matches = {
543 			DMI_MATCH(DMI_BOARD_NAME, "EXOPG06411"),
544 			DMI_MATCH(DMI_BIOS_VERSION, "Lucid-CE-133"),
545 		},
546 	},
547 	{
548 		/*  Pegatron Lucid (Ordissimo AIRIS) */
549 		.matches = {
550 			DMI_MATCH(DMI_BOARD_NAME, "M11JB"),
551 			DMI_MATCH(DMI_BIOS_VERSION, "Lucid-GE-133"),
552 		},
553 	},
554 	{ }
555 };
556 
557 static void __devinit ehci_bios_handoff(struct pci_dev *pdev,
558 					void __iomem *op_reg_base,
559 					u32 cap, u8 offset)
560 {
561 	int try_handoff = 1, tried_handoff = 0;
562 
563 	/* The Pegatron Lucid tablet sporadically waits for 98 seconds trying
564 	 * the handoff on its unused controller.  Skip it. */
565 	if (pdev->vendor == 0x8086 && pdev->device == 0x283a) {
566 		if (dmi_check_system(ehci_dmi_nohandoff_table))
567 			try_handoff = 0;
568 	}
569 
570 	if (try_handoff && (cap & EHCI_USBLEGSUP_BIOS)) {
571 		dev_dbg(&pdev->dev, "EHCI: BIOS handoff\n");
572 
573 #if 0
574 /* aleksey_gorelov@phoenix.com reports that some systems need SMI forced on,
575  * but that seems dubious in general (the BIOS left it off intentionally)
576  * and is known to prevent some systems from booting.  so we won't do this
577  * unless maybe we can determine when we're on a system that needs SMI forced.
578  */
579 		/* BIOS workaround (?): be sure the pre-Linux code
580 		 * receives the SMI
581 		 */
582 		pci_read_config_dword(pdev, offset + EHCI_USBLEGCTLSTS, &val);
583 		pci_write_config_dword(pdev, offset + EHCI_USBLEGCTLSTS,
584 				       val | EHCI_USBLEGCTLSTS_SOOE);
585 #endif
586 
587 		/* some systems get upset if this semaphore is
588 		 * set for any other reason than forcing a BIOS
589 		 * handoff..
590 		 */
591 		pci_write_config_byte(pdev, offset + 3, 1);
592 	}
593 
594 	/* if boot firmware now owns EHCI, spin till it hands it over. */
595 	if (try_handoff) {
596 		int msec = 1000;
597 		while ((cap & EHCI_USBLEGSUP_BIOS) && (msec > 0)) {
598 			tried_handoff = 1;
599 			msleep(10);
600 			msec -= 10;
601 			pci_read_config_dword(pdev, offset, &cap);
602 		}
603 	}
604 
605 	if (cap & EHCI_USBLEGSUP_BIOS) {
606 		/* well, possibly buggy BIOS... try to shut it down,
607 		 * and hope nothing goes too wrong
608 		 */
609 		if (try_handoff)
610 			dev_warn(&pdev->dev, "EHCI: BIOS handoff failed"
611 				 " (BIOS bug?) %08x\n", cap);
612 		pci_write_config_byte(pdev, offset + 2, 0);
613 	}
614 
615 	/* just in case, always disable EHCI SMIs */
616 	pci_write_config_dword(pdev, offset + EHCI_USBLEGCTLSTS, 0);
617 
618 	/* If the BIOS ever owned the controller then we can't expect
619 	 * any power sessions to remain intact.
620 	 */
621 	if (tried_handoff)
622 		writel(0, op_reg_base + EHCI_CONFIGFLAG);
623 }
624 
625 static void __devinit quirk_usb_disable_ehci(struct pci_dev *pdev)
626 {
627 	void __iomem *base, *op_reg_base;
628 	u32	hcc_params, cap, val;
629 	u8	offset, cap_length;
630 	int	wait_time, delta, count = 256/4;
631 
632 	if (!mmio_resource_enabled(pdev, 0))
633 		return;
634 
635 	base = pci_ioremap_bar(pdev, 0);
636 	if (base == NULL)
637 		return;
638 
639 	cap_length = readb(base);
640 	op_reg_base = base + cap_length;
641 
642 	/* EHCI 0.96 and later may have "extended capabilities"
643 	 * spec section 5.1 explains the bios handoff, e.g. for
644 	 * booting from USB disk or using a usb keyboard
645 	 */
646 	hcc_params = readl(base + EHCI_HCC_PARAMS);
647 	offset = (hcc_params >> 8) & 0xff;
648 	while (offset && --count) {
649 		pci_read_config_dword(pdev, offset, &cap);
650 
651 		switch (cap & 0xff) {
652 		case 1:
653 			ehci_bios_handoff(pdev, op_reg_base, cap, offset);
654 			break;
655 		case 0: /* Illegal reserved cap, set cap=0 so we exit */
656 			cap = 0; /* then fallthrough... */
657 		default:
658 			dev_warn(&pdev->dev, "EHCI: unrecognized capability "
659 				 "%02x\n", cap & 0xff);
660 		}
661 		offset = (cap >> 8) & 0xff;
662 	}
663 	if (!count)
664 		dev_printk(KERN_DEBUG, &pdev->dev, "EHCI: capability loop?\n");
665 
666 	/*
667 	 * halt EHCI & disable its interrupts in any case
668 	 */
669 	val = readl(op_reg_base + EHCI_USBSTS);
670 	if ((val & EHCI_USBSTS_HALTED) == 0) {
671 		val = readl(op_reg_base + EHCI_USBCMD);
672 		val &= ~EHCI_USBCMD_RUN;
673 		writel(val, op_reg_base + EHCI_USBCMD);
674 
675 		wait_time = 2000;
676 		delta = 100;
677 		do {
678 			writel(0x3f, op_reg_base + EHCI_USBSTS);
679 			udelay(delta);
680 			wait_time -= delta;
681 			val = readl(op_reg_base + EHCI_USBSTS);
682 			if ((val == ~(u32)0) || (val & EHCI_USBSTS_HALTED)) {
683 				break;
684 			}
685 		} while (wait_time > 0);
686 	}
687 	writel(0, op_reg_base + EHCI_USBINTR);
688 	writel(0x3f, op_reg_base + EHCI_USBSTS);
689 
690 	iounmap(base);
691 }
692 
693 /*
694  * handshake - spin reading a register until handshake completes
695  * @ptr: address of hc register to be read
696  * @mask: bits to look at in result of read
697  * @done: value of those bits when handshake succeeds
698  * @wait_usec: timeout in microseconds
699  * @delay_usec: delay in microseconds to wait between polling
700  *
701  * Polls a register every delay_usec microseconds.
702  * Returns 0 when the mask bits have the value done.
703  * Returns -ETIMEDOUT if this condition is not true after
704  * wait_usec microseconds have passed.
705  */
706 static int handshake(void __iomem *ptr, u32 mask, u32 done,
707 		int wait_usec, int delay_usec)
708 {
709 	u32	result;
710 
711 	do {
712 		result = readl(ptr);
713 		result &= mask;
714 		if (result == done)
715 			return 0;
716 		udelay(delay_usec);
717 		wait_usec -= delay_usec;
718 	} while (wait_usec > 0);
719 	return -ETIMEDOUT;
720 }
721 
722 bool usb_is_intel_switchable_xhci(struct pci_dev *pdev)
723 {
724 	return pdev->class == PCI_CLASS_SERIAL_USB_XHCI &&
725 		pdev->vendor == PCI_VENDOR_ID_INTEL &&
726 		pdev->device == PCI_DEVICE_ID_INTEL_PANTHERPOINT_XHCI;
727 }
728 EXPORT_SYMBOL_GPL(usb_is_intel_switchable_xhci);
729 
730 /*
731  * Intel's Panther Point chipset has two host controllers (EHCI and xHCI) that
732  * share some number of ports.  These ports can be switched between either
733  * controller.  Not all of the ports under the EHCI host controller may be
734  * switchable.
735  *
736  * The ports should be switched over to xHCI before PCI probes for any device
737  * start.  This avoids active devices under EHCI being disconnected during the
738  * port switchover, which could cause loss of data on USB storage devices, or
739  * failed boot when the root file system is on a USB mass storage device and is
740  * enumerated under EHCI first.
741  *
742  * We write into the xHC's PCI configuration space in some Intel-specific
743  * registers to switch the ports over.  The USB 3.0 terminations and the USB
744  * 2.0 data wires are switched separately.  We want to enable the SuperSpeed
745  * terminations before switching the USB 2.0 wires over, so that USB 3.0
746  * devices connect at SuperSpeed, rather than at USB 2.0 speeds.
747  */
748 void usb_enable_xhci_ports(struct pci_dev *xhci_pdev)
749 {
750 	u32		ports_available;
751 
752 	ports_available = 0xffffffff;
753 	/* Write USB3_PSSEN, the USB 3.0 Port SuperSpeed Enable
754 	 * Register, to turn on SuperSpeed terminations for all
755 	 * available ports.
756 	 */
757 	pci_write_config_dword(xhci_pdev, USB_INTEL_USB3_PSSEN,
758 			cpu_to_le32(ports_available));
759 
760 	pci_read_config_dword(xhci_pdev, USB_INTEL_USB3_PSSEN,
761 			&ports_available);
762 	dev_dbg(&xhci_pdev->dev, "USB 3.0 ports that are now enabled "
763 			"under xHCI: 0x%x\n", ports_available);
764 
765 	ports_available = 0xffffffff;
766 	/* Write XUSB2PR, the xHC USB 2.0 Port Routing Register, to
767 	 * switch the USB 2.0 power and data lines over to the xHCI
768 	 * host.
769 	 */
770 	pci_write_config_dword(xhci_pdev, USB_INTEL_XUSB2PR,
771 			cpu_to_le32(ports_available));
772 
773 	pci_read_config_dword(xhci_pdev, USB_INTEL_XUSB2PR,
774 			&ports_available);
775 	dev_dbg(&xhci_pdev->dev, "USB 2.0 ports that are now switched over "
776 			"to xHCI: 0x%x\n", ports_available);
777 }
778 EXPORT_SYMBOL_GPL(usb_enable_xhci_ports);
779 
780 /**
781  * PCI Quirks for xHCI.
782  *
783  * Takes care of the handoff between the Pre-OS (i.e. BIOS) and the OS.
784  * It signals to the BIOS that the OS wants control of the host controller,
785  * and then waits 5 seconds for the BIOS to hand over control.
786  * If we timeout, assume the BIOS is broken and take control anyway.
787  */
788 static void __devinit quirk_usb_handoff_xhci(struct pci_dev *pdev)
789 {
790 	void __iomem *base;
791 	int ext_cap_offset;
792 	void __iomem *op_reg_base;
793 	u32 val;
794 	int timeout;
795 
796 	if (!mmio_resource_enabled(pdev, 0))
797 		return;
798 
799 	base = ioremap_nocache(pci_resource_start(pdev, 0),
800 				pci_resource_len(pdev, 0));
801 	if (base == NULL)
802 		return;
803 
804 	/*
805 	 * Find the Legacy Support Capability register -
806 	 * this is optional for xHCI host controllers.
807 	 */
808 	ext_cap_offset = xhci_find_next_cap_offset(base, XHCI_HCC_PARAMS_OFFSET);
809 	do {
810 		if (!ext_cap_offset)
811 			/* We've reached the end of the extended capabilities */
812 			goto hc_init;
813 		val = readl(base + ext_cap_offset);
814 		if (XHCI_EXT_CAPS_ID(val) == XHCI_EXT_CAPS_LEGACY)
815 			break;
816 		ext_cap_offset = xhci_find_next_cap_offset(base, ext_cap_offset);
817 	} while (1);
818 
819 	/* If the BIOS owns the HC, signal that the OS wants it, and wait */
820 	if (val & XHCI_HC_BIOS_OWNED) {
821 		writel(val | XHCI_HC_OS_OWNED, base + ext_cap_offset);
822 
823 		/* Wait for 5 seconds with 10 microsecond polling interval */
824 		timeout = handshake(base + ext_cap_offset, XHCI_HC_BIOS_OWNED,
825 				0, 5000, 10);
826 
827 		/* Assume a buggy BIOS and take HC ownership anyway */
828 		if (timeout) {
829 			dev_warn(&pdev->dev, "xHCI BIOS handoff failed"
830 					" (BIOS bug ?) %08x\n", val);
831 			writel(val & ~XHCI_HC_BIOS_OWNED, base + ext_cap_offset);
832 		}
833 	}
834 
835 	/* Disable any BIOS SMIs */
836 	writel(XHCI_LEGACY_DISABLE_SMI,
837 			base + ext_cap_offset + XHCI_LEGACY_CONTROL_OFFSET);
838 
839 	if (usb_is_intel_switchable_xhci(pdev))
840 		usb_enable_xhci_ports(pdev);
841 hc_init:
842 	op_reg_base = base + XHCI_HC_LENGTH(readl(base));
843 
844 	/* Wait for the host controller to be ready before writing any
845 	 * operational or runtime registers.  Wait 5 seconds and no more.
846 	 */
847 	timeout = handshake(op_reg_base + XHCI_STS_OFFSET, XHCI_STS_CNR, 0,
848 			5000, 10);
849 	/* Assume a buggy HC and start HC initialization anyway */
850 	if (timeout) {
851 		val = readl(op_reg_base + XHCI_STS_OFFSET);
852 		dev_warn(&pdev->dev,
853 				"xHCI HW not ready after 5 sec (HC bug?) "
854 				"status = 0x%x\n", val);
855 	}
856 
857 	/* Send the halt and disable interrupts command */
858 	val = readl(op_reg_base + XHCI_CMD_OFFSET);
859 	val &= ~(XHCI_CMD_RUN | XHCI_IRQS);
860 	writel(val, op_reg_base + XHCI_CMD_OFFSET);
861 
862 	/* Wait for the HC to halt - poll every 125 usec (one microframe). */
863 	timeout = handshake(op_reg_base + XHCI_STS_OFFSET, XHCI_STS_HALT, 1,
864 			XHCI_MAX_HALT_USEC, 125);
865 	if (timeout) {
866 		val = readl(op_reg_base + XHCI_STS_OFFSET);
867 		dev_warn(&pdev->dev,
868 				"xHCI HW did not halt within %d usec "
869 				"status = 0x%x\n", XHCI_MAX_HALT_USEC, val);
870 	}
871 
872 	iounmap(base);
873 }
874 
875 static void __devinit quirk_usb_early_handoff(struct pci_dev *pdev)
876 {
877 	if (pdev->class == PCI_CLASS_SERIAL_USB_UHCI)
878 		quirk_usb_handoff_uhci(pdev);
879 	else if (pdev->class == PCI_CLASS_SERIAL_USB_OHCI)
880 		quirk_usb_handoff_ohci(pdev);
881 	else if (pdev->class == PCI_CLASS_SERIAL_USB_EHCI)
882 		quirk_usb_disable_ehci(pdev);
883 	else if (pdev->class == PCI_CLASS_SERIAL_USB_XHCI)
884 		quirk_usb_handoff_xhci(pdev);
885 }
886 DECLARE_PCI_FIXUP_FINAL(PCI_ANY_ID, PCI_ANY_ID, quirk_usb_early_handoff);
887