xref: /linux/drivers/usb/host/pci-quirks.c (revision 858259cf7d1c443c836a2022b78cb281f0a9b95e)
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/config.h>
12 #ifdef CONFIG_USB_DEBUG
13 #define DEBUG
14 #else
15 #undef DEBUG
16 #endif
17 
18 #include <linux/types.h>
19 #include <linux/kernel.h>
20 #include <linux/pci.h>
21 #include <linux/init.h>
22 #include <linux/delay.h>
23 #include <linux/acpi.h>
24 
25 
26 #define UHCI_USBLEGSUP		0xc0		/* legacy support */
27 #define UHCI_USBCMD		0		/* command register */
28 #define UHCI_USBINTR		4		/* interrupt register */
29 #define UHCI_USBLEGSUP_RWC	0x8f00		/* the R/WC bits */
30 #define UHCI_USBLEGSUP_RO	0x5040		/* R/O and reserved bits */
31 #define UHCI_USBCMD_RUN		0x0001		/* RUN/STOP bit */
32 #define UHCI_USBCMD_HCRESET	0x0002		/* Host Controller reset */
33 #define UHCI_USBCMD_EGSM	0x0008		/* Global Suspend Mode */
34 #define UHCI_USBCMD_CONFIGURE	0x0040		/* Config Flag */
35 #define UHCI_USBINTR_RESUME	0x0002		/* Resume interrupt enable */
36 
37 #define OHCI_CONTROL		0x04
38 #define OHCI_CMDSTATUS		0x08
39 #define OHCI_INTRSTATUS		0x0c
40 #define OHCI_INTRENABLE		0x10
41 #define OHCI_INTRDISABLE	0x14
42 #define OHCI_OCR		(1 << 3)	/* ownership change request */
43 #define OHCI_CTRL_RWC		(1 << 9)	/* remote wakeup connected */
44 #define OHCI_CTRL_IR		(1 << 8)	/* interrupt routing */
45 #define OHCI_INTR_OC		(1 << 30)	/* ownership change */
46 
47 #define EHCI_HCC_PARAMS		0x08		/* extended capabilities */
48 #define EHCI_USBCMD		0		/* command register */
49 #define EHCI_USBCMD_RUN		(1 << 0)	/* RUN/STOP bit */
50 #define EHCI_USBSTS		4		/* status register */
51 #define EHCI_USBSTS_HALTED	(1 << 12)	/* HCHalted bit */
52 #define EHCI_USBINTR		8		/* interrupt 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 
60 /*
61  * Make sure the controller is completely inactive, unable to
62  * generate interrupts or do DMA.
63  */
64 void uhci_reset_hc(struct pci_dev *pdev, unsigned long base)
65 {
66 	/* Turn off PIRQ enable and SMI enable.  (This also turns off the
67 	 * BIOS's USB Legacy Support.)  Turn off all the R/WC bits too.
68 	 */
69 	pci_write_config_word(pdev, UHCI_USBLEGSUP, UHCI_USBLEGSUP_RWC);
70 
71 	/* Reset the HC - this will force us to get a
72 	 * new notification of any already connected
73 	 * ports due to the virtual disconnect that it
74 	 * implies.
75 	 */
76 	outw(UHCI_USBCMD_HCRESET, base + UHCI_USBCMD);
77 	mb();
78 	udelay(5);
79 	if (inw(base + UHCI_USBCMD) & UHCI_USBCMD_HCRESET)
80 		dev_warn(&pdev->dev, "HCRESET not completed yet!\n");
81 
82 	/* Just to be safe, disable interrupt requests and
83 	 * make sure the controller is stopped.
84 	 */
85 	outw(0, base + UHCI_USBINTR);
86 	outw(0, base + UHCI_USBCMD);
87 }
88 EXPORT_SYMBOL_GPL(uhci_reset_hc);
89 
90 /*
91  * Initialize a controller that was newly discovered or has just been
92  * resumed.  In either case we can't be sure of its previous state.
93  *
94  * Returns: 1 if the controller was reset, 0 otherwise.
95  */
96 int uhci_check_and_reset_hc(struct pci_dev *pdev, unsigned long base)
97 {
98 	u16 legsup;
99 	unsigned int cmd, intr;
100 
101 	/*
102 	 * When restarting a suspended controller, we expect all the
103 	 * settings to be the same as we left them:
104 	 *
105 	 *	PIRQ and SMI disabled, no R/W bits set in USBLEGSUP;
106 	 *	Controller is stopped and configured with EGSM set;
107 	 *	No interrupts enabled except possibly Resume Detect.
108 	 *
109 	 * If any of these conditions are violated we do a complete reset.
110 	 */
111 	pci_read_config_word(pdev, UHCI_USBLEGSUP, &legsup);
112 	if (legsup & ~(UHCI_USBLEGSUP_RO | UHCI_USBLEGSUP_RWC)) {
113 		dev_dbg(&pdev->dev, "%s: legsup = 0x%04x\n",
114 				__FUNCTION__, legsup);
115 		goto reset_needed;
116 	}
117 
118 	cmd = inw(base + UHCI_USBCMD);
119 	if ((cmd & UHCI_USBCMD_RUN) || !(cmd & UHCI_USBCMD_CONFIGURE) ||
120 			!(cmd & UHCI_USBCMD_EGSM)) {
121 		dev_dbg(&pdev->dev, "%s: cmd = 0x%04x\n",
122 				__FUNCTION__, cmd);
123 		goto reset_needed;
124 	}
125 
126 	intr = inw(base + UHCI_USBINTR);
127 	if (intr & (~UHCI_USBINTR_RESUME)) {
128 		dev_dbg(&pdev->dev, "%s: intr = 0x%04x\n",
129 				__FUNCTION__, intr);
130 		goto reset_needed;
131 	}
132 	return 0;
133 
134 reset_needed:
135 	dev_dbg(&pdev->dev, "Performing full reset\n");
136 	uhci_reset_hc(pdev, base);
137 	return 1;
138 }
139 EXPORT_SYMBOL_GPL(uhci_check_and_reset_hc);
140 
141 static inline int io_type_enabled(struct pci_dev *pdev, unsigned int mask)
142 {
143 	u16 cmd;
144 	return !pci_read_config_word(pdev, PCI_COMMAND, &cmd) && (cmd & mask);
145 }
146 
147 #define pio_enabled(dev) io_type_enabled(dev, PCI_COMMAND_IO)
148 #define mmio_enabled(dev) io_type_enabled(dev, PCI_COMMAND_MEMORY)
149 
150 static void __devinit quirk_usb_handoff_uhci(struct pci_dev *pdev)
151 {
152 	unsigned long base = 0;
153 	int i;
154 
155 	if (!pio_enabled(pdev))
156 		return;
157 
158 	for (i = 0; i < PCI_ROM_RESOURCE; i++)
159 		if ((pci_resource_flags(pdev, i) & IORESOURCE_IO)) {
160 			base = pci_resource_start(pdev, i);
161 			break;
162 		}
163 
164 	if (base)
165 		uhci_check_and_reset_hc(pdev, base);
166 }
167 
168 static int __devinit mmio_resource_enabled(struct pci_dev *pdev, int idx)
169 {
170 	return pci_resource_start(pdev, idx) && mmio_enabled(pdev);
171 }
172 
173 static void __devinit quirk_usb_handoff_ohci(struct pci_dev *pdev)
174 {
175 	void __iomem *base;
176 	int wait_time;
177 	u32 control;
178 
179 	if (!mmio_resource_enabled(pdev, 0))
180 		return;
181 
182 	base = ioremap_nocache(pci_resource_start(pdev, 0),
183 				     pci_resource_len(pdev, 0));
184 	if (base == NULL) return;
185 
186 /* On PA-RISC, PDC can leave IR set incorrectly; ignore it there. */
187 #ifndef __hppa__
188 	control = readl(base + OHCI_CONTROL);
189 	if (control & OHCI_CTRL_IR) {
190 		wait_time = 500; /* arbitrary; 5 seconds */
191 		writel(OHCI_INTR_OC, base + OHCI_INTRENABLE);
192 		writel(OHCI_OCR, base + OHCI_CMDSTATUS);
193 		while (wait_time > 0 &&
194 				readl(base + OHCI_CONTROL) & OHCI_CTRL_IR) {
195 			wait_time -= 10;
196 			msleep(10);
197 		}
198 		if (wait_time <= 0)
199 			printk(KERN_WARNING "%s %s: early BIOS handoff "
200 					"failed (BIOS bug ?)\n",
201 					pdev->dev.bus_id, "OHCI");
202 
203 		/* reset controller, preserving RWC */
204 		writel(control & OHCI_CTRL_RWC, base + OHCI_CONTROL);
205 	}
206 #endif
207 
208 	/*
209 	 * disable interrupts
210 	 */
211 	writel(~(u32)0, base + OHCI_INTRDISABLE);
212 	writel(~(u32)0, base + OHCI_INTRSTATUS);
213 
214 	iounmap(base);
215 }
216 
217 static void __devinit quirk_usb_disable_ehci(struct pci_dev *pdev)
218 {
219 	int wait_time, delta;
220 	void __iomem *base, *op_reg_base;
221 	u32 hcc_params, val, temp;
222 	u8 cap_length;
223 
224 	if (!mmio_resource_enabled(pdev, 0))
225 		return;
226 
227 	base = ioremap_nocache(pci_resource_start(pdev, 0),
228 				pci_resource_len(pdev, 0));
229 	if (base == NULL) return;
230 
231 	cap_length = readb(base);
232 	op_reg_base = base + cap_length;
233 	hcc_params = readl(base + EHCI_HCC_PARAMS);
234 	hcc_params = (hcc_params >> 8) & 0xff;
235 	if (hcc_params) {
236 		pci_read_config_dword(pdev,
237 					hcc_params + EHCI_USBLEGSUP,
238 					&val);
239 		if (((val & 0xff) == 1) && (val & EHCI_USBLEGSUP_BIOS)) {
240 			/*
241 			 * Ok, BIOS is in smm mode, try to hand off...
242 			 */
243 			pci_read_config_dword(pdev,
244 						hcc_params + EHCI_USBLEGCTLSTS,
245 						&temp);
246 			pci_write_config_dword(pdev,
247 						hcc_params + EHCI_USBLEGCTLSTS,
248 						temp | EHCI_USBLEGCTLSTS_SOOE);
249 			val |= EHCI_USBLEGSUP_OS;
250 			pci_write_config_dword(pdev,
251 						hcc_params + EHCI_USBLEGSUP,
252 						val);
253 
254 			wait_time = 500;
255 			do {
256 				msleep(10);
257 				wait_time -= 10;
258 				pci_read_config_dword(pdev,
259 						hcc_params + EHCI_USBLEGSUP,
260 						&val);
261 			} while (wait_time && (val & EHCI_USBLEGSUP_BIOS));
262 			if (!wait_time) {
263 				/*
264 				 * well, possibly buggy BIOS...
265 				 */
266 				printk(KERN_WARNING "%s %s: early BIOS handoff "
267 						"failed (BIOS bug ?)\n",
268 					pdev->dev.bus_id, "EHCI");
269 				pci_write_config_dword(pdev,
270 						hcc_params + EHCI_USBLEGSUP,
271 						EHCI_USBLEGSUP_OS);
272 				pci_write_config_dword(pdev,
273 						hcc_params + EHCI_USBLEGCTLSTS,
274 						0);
275 			}
276 		}
277 	}
278 
279 	/*
280 	 * halt EHCI & disable its interrupts in any case
281 	 */
282 	val = readl(op_reg_base + EHCI_USBSTS);
283 	if ((val & EHCI_USBSTS_HALTED) == 0) {
284 		val = readl(op_reg_base + EHCI_USBCMD);
285 		val &= ~EHCI_USBCMD_RUN;
286 		writel(val, op_reg_base + EHCI_USBCMD);
287 
288 		wait_time = 2000;
289 		delta = 100;
290 		do {
291 			writel(0x3f, op_reg_base + EHCI_USBSTS);
292 			udelay(delta);
293 			wait_time -= delta;
294 			val = readl(op_reg_base + EHCI_USBSTS);
295 			if ((val == ~(u32)0) || (val & EHCI_USBSTS_HALTED)) {
296 				break;
297 			}
298 		} while (wait_time > 0);
299 	}
300 	writel(0, op_reg_base + EHCI_USBINTR);
301 	writel(0x3f, op_reg_base + EHCI_USBSTS);
302 
303 	iounmap(base);
304 
305 	return;
306 }
307 
308 
309 
310 static void __devinit quirk_usb_early_handoff(struct pci_dev *pdev)
311 {
312 	if (pdev->class == PCI_CLASS_SERIAL_USB_UHCI)
313 		quirk_usb_handoff_uhci(pdev);
314 	else if (pdev->class == PCI_CLASS_SERIAL_USB_OHCI)
315 		quirk_usb_handoff_ohci(pdev);
316 	else if (pdev->class == PCI_CLASS_SERIAL_USB_EHCI)
317 		quirk_usb_disable_ehci(pdev);
318 }
319 DECLARE_PCI_FIXUP_FINAL(PCI_ANY_ID, PCI_ANY_ID, quirk_usb_early_handoff);
320