xref: /openbmc/linux/drivers/usb/host/pci-quirks.c (revision 87c2ce3b)
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 #include <linux/types.h>
13 #include <linux/kernel.h>
14 #include <linux/pci.h>
15 #include <linux/init.h>
16 #include <linux/delay.h>
17 #include <linux/acpi.h>
18 
19 
20 #define UHCI_USBLEGSUP		0xc0		/* legacy support */
21 #define UHCI_USBCMD		0		/* command register */
22 #define UHCI_USBINTR		4		/* interrupt register */
23 #define UHCI_USBLEGSUP_RWC	0x8f00		/* the R/WC bits */
24 #define UHCI_USBLEGSUP_RO	0x5040		/* R/O and reserved bits */
25 #define UHCI_USBCMD_RUN		0x0001		/* RUN/STOP bit */
26 #define UHCI_USBCMD_HCRESET	0x0002		/* Host Controller reset */
27 #define UHCI_USBCMD_EGSM	0x0008		/* Global Suspend Mode */
28 #define UHCI_USBCMD_CONFIGURE	0x0040		/* Config Flag */
29 #define UHCI_USBINTR_RESUME	0x0002		/* Resume interrupt enable */
30 
31 #define OHCI_CONTROL		0x04
32 #define OHCI_CMDSTATUS		0x08
33 #define OHCI_INTRSTATUS		0x0c
34 #define OHCI_INTRENABLE		0x10
35 #define OHCI_INTRDISABLE	0x14
36 #define OHCI_OCR		(1 << 3)	/* ownership change request */
37 #define OHCI_CTRL_RWC		(1 << 9)	/* remote wakeup connected */
38 #define OHCI_CTRL_IR		(1 << 8)	/* interrupt routing */
39 #define OHCI_INTR_OC		(1 << 30)	/* ownership change */
40 
41 #define EHCI_HCC_PARAMS		0x08		/* extended capabilities */
42 #define EHCI_USBCMD		0		/* command register */
43 #define EHCI_USBCMD_RUN		(1 << 0)	/* RUN/STOP bit */
44 #define EHCI_USBSTS		4		/* status register */
45 #define EHCI_USBSTS_HALTED	(1 << 12)	/* HCHalted bit */
46 #define EHCI_USBINTR		8		/* interrupt register */
47 #define EHCI_USBLEGSUP		0		/* legacy support register */
48 #define EHCI_USBLEGSUP_BIOS	(1 << 16)	/* BIOS semaphore */
49 #define EHCI_USBLEGSUP_OS	(1 << 24)	/* OS semaphore */
50 #define EHCI_USBLEGCTLSTS	4		/* legacy control/status */
51 #define EHCI_USBLEGCTLSTS_SOOE	(1 << 13)	/* SMI on ownership change */
52 
53 
54 /*
55  * Make sure the controller is completely inactive, unable to
56  * generate interrupts or do DMA.
57  */
58 void uhci_reset_hc(struct pci_dev *pdev, unsigned long base)
59 {
60 	/* Turn off PIRQ enable and SMI enable.  (This also turns off the
61 	 * BIOS's USB Legacy Support.)  Turn off all the R/WC bits too.
62 	 */
63 	pci_write_config_word(pdev, UHCI_USBLEGSUP, UHCI_USBLEGSUP_RWC);
64 
65 	/* Reset the HC - this will force us to get a
66 	 * new notification of any already connected
67 	 * ports due to the virtual disconnect that it
68 	 * implies.
69 	 */
70 	outw(UHCI_USBCMD_HCRESET, base + UHCI_USBCMD);
71 	mb();
72 	udelay(5);
73 	if (inw(base + UHCI_USBCMD) & UHCI_USBCMD_HCRESET)
74 		dev_warn(&pdev->dev, "HCRESET not completed yet!\n");
75 
76 	/* Just to be safe, disable interrupt requests and
77 	 * make sure the controller is stopped.
78 	 */
79 	outw(0, base + UHCI_USBINTR);
80 	outw(0, base + UHCI_USBCMD);
81 }
82 EXPORT_SYMBOL_GPL(uhci_reset_hc);
83 
84 /*
85  * Initialize a controller that was newly discovered or has just been
86  * resumed.  In either case we can't be sure of its previous state.
87  *
88  * Returns: 1 if the controller was reset, 0 otherwise.
89  */
90 int uhci_check_and_reset_hc(struct pci_dev *pdev, unsigned long base)
91 {
92 	u16 legsup;
93 	unsigned int cmd, intr;
94 
95 	/*
96 	 * When restarting a suspended controller, we expect all the
97 	 * settings to be the same as we left them:
98 	 *
99 	 *	PIRQ and SMI disabled, no R/W bits set in USBLEGSUP;
100 	 *	Controller is stopped and configured with EGSM set;
101 	 *	No interrupts enabled except possibly Resume Detect.
102 	 *
103 	 * If any of these conditions are violated we do a complete reset.
104 	 */
105 	pci_read_config_word(pdev, UHCI_USBLEGSUP, &legsup);
106 	if (legsup & ~(UHCI_USBLEGSUP_RO | UHCI_USBLEGSUP_RWC)) {
107 		dev_dbg(&pdev->dev, "%s: legsup = 0x%04x\n",
108 				__FUNCTION__, legsup);
109 		goto reset_needed;
110 	}
111 
112 	cmd = inw(base + UHCI_USBCMD);
113 	if ((cmd & UHCI_USBCMD_RUN) || !(cmd & UHCI_USBCMD_CONFIGURE) ||
114 			!(cmd & UHCI_USBCMD_EGSM)) {
115 		dev_dbg(&pdev->dev, "%s: cmd = 0x%04x\n",
116 				__FUNCTION__, cmd);
117 		goto reset_needed;
118 	}
119 
120 	intr = inw(base + UHCI_USBINTR);
121 	if (intr & (~UHCI_USBINTR_RESUME)) {
122 		dev_dbg(&pdev->dev, "%s: intr = 0x%04x\n",
123 				__FUNCTION__, intr);
124 		goto reset_needed;
125 	}
126 	return 0;
127 
128 reset_needed:
129 	dev_dbg(&pdev->dev, "Performing full reset\n");
130 	uhci_reset_hc(pdev, base);
131 	return 1;
132 }
133 EXPORT_SYMBOL_GPL(uhci_check_and_reset_hc);
134 
135 static inline int io_type_enabled(struct pci_dev *pdev, unsigned int mask)
136 {
137 	u16 cmd;
138 	return !pci_read_config_word(pdev, PCI_COMMAND, &cmd) && (cmd & mask);
139 }
140 
141 #define pio_enabled(dev) io_type_enabled(dev, PCI_COMMAND_IO)
142 #define mmio_enabled(dev) io_type_enabled(dev, PCI_COMMAND_MEMORY)
143 
144 static void __devinit quirk_usb_handoff_uhci(struct pci_dev *pdev)
145 {
146 	unsigned long base = 0;
147 	int i;
148 
149 	if (!pio_enabled(pdev))
150 		return;
151 
152 	for (i = 0; i < PCI_ROM_RESOURCE; i++)
153 		if ((pci_resource_flags(pdev, i) & IORESOURCE_IO)) {
154 			base = pci_resource_start(pdev, i);
155 			break;
156 		}
157 
158 	if (base)
159 		uhci_check_and_reset_hc(pdev, base);
160 }
161 
162 static int __devinit mmio_resource_enabled(struct pci_dev *pdev, int idx)
163 {
164 	return pci_resource_start(pdev, idx) && mmio_enabled(pdev);
165 }
166 
167 static void __devinit quirk_usb_handoff_ohci(struct pci_dev *pdev)
168 {
169 	void __iomem *base;
170 	int wait_time;
171 	u32 control;
172 
173 	if (!mmio_resource_enabled(pdev, 0))
174 		return;
175 
176 	base = ioremap_nocache(pci_resource_start(pdev, 0),
177 				     pci_resource_len(pdev, 0));
178 	if (base == NULL) return;
179 
180 /* On PA-RISC, PDC can leave IR set incorrectly; ignore it there. */
181 #ifndef __hppa__
182 	control = readl(base + OHCI_CONTROL);
183 	if (control & OHCI_CTRL_IR) {
184 		wait_time = 500; /* arbitrary; 5 seconds */
185 		writel(OHCI_INTR_OC, base + OHCI_INTRENABLE);
186 		writel(OHCI_OCR, base + OHCI_CMDSTATUS);
187 		while (wait_time > 0 &&
188 				readl(base + OHCI_CONTROL) & OHCI_CTRL_IR) {
189 			wait_time -= 10;
190 			msleep(10);
191 		}
192 		if (wait_time <= 0)
193 			printk(KERN_WARNING "%s %s: early BIOS handoff "
194 					"failed (BIOS bug ?)\n",
195 					pdev->dev.bus_id, "OHCI");
196 
197 		/* reset controller, preserving RWC */
198 		writel(control & OHCI_CTRL_RWC, base + OHCI_CONTROL);
199 	}
200 #endif
201 
202 	/*
203 	 * disable interrupts
204 	 */
205 	writel(~(u32)0, base + OHCI_INTRDISABLE);
206 	writel(~(u32)0, base + OHCI_INTRSTATUS);
207 
208 	iounmap(base);
209 }
210 
211 static void __devinit quirk_usb_disable_ehci(struct pci_dev *pdev)
212 {
213 	int wait_time, delta;
214 	void __iomem *base, *op_reg_base;
215 	u32 hcc_params, val, temp;
216 	u8 cap_length;
217 
218 	if (!mmio_resource_enabled(pdev, 0))
219 		return;
220 
221 	base = ioremap_nocache(pci_resource_start(pdev, 0),
222 				pci_resource_len(pdev, 0));
223 	if (base == NULL) return;
224 
225 	cap_length = readb(base);
226 	op_reg_base = base + cap_length;
227 	hcc_params = readl(base + EHCI_HCC_PARAMS);
228 	hcc_params = (hcc_params >> 8) & 0xff;
229 	if (hcc_params) {
230 		pci_read_config_dword(pdev,
231 					hcc_params + EHCI_USBLEGSUP,
232 					&val);
233 		if (((val & 0xff) == 1) && (val & EHCI_USBLEGSUP_BIOS)) {
234 			/*
235 			 * Ok, BIOS is in smm mode, try to hand off...
236 			 */
237 			pci_read_config_dword(pdev,
238 						hcc_params + EHCI_USBLEGCTLSTS,
239 						&temp);
240 			pci_write_config_dword(pdev,
241 						hcc_params + EHCI_USBLEGCTLSTS,
242 						temp | EHCI_USBLEGCTLSTS_SOOE);
243 			val |= EHCI_USBLEGSUP_OS;
244 			pci_write_config_dword(pdev,
245 						hcc_params + EHCI_USBLEGSUP,
246 						val);
247 
248 			wait_time = 500;
249 			do {
250 				msleep(10);
251 				wait_time -= 10;
252 				pci_read_config_dword(pdev,
253 						hcc_params + EHCI_USBLEGSUP,
254 						&val);
255 			} while (wait_time && (val & EHCI_USBLEGSUP_BIOS));
256 			if (!wait_time) {
257 				/*
258 				 * well, possibly buggy BIOS...
259 				 */
260 				printk(KERN_WARNING "%s %s: early BIOS handoff "
261 						"failed (BIOS bug ?)\n",
262 					pdev->dev.bus_id, "EHCI");
263 				pci_write_config_dword(pdev,
264 						hcc_params + EHCI_USBLEGSUP,
265 						EHCI_USBLEGSUP_OS);
266 				pci_write_config_dword(pdev,
267 						hcc_params + EHCI_USBLEGCTLSTS,
268 						0);
269 			}
270 		}
271 	}
272 
273 	/*
274 	 * halt EHCI & disable its interrupts in any case
275 	 */
276 	val = readl(op_reg_base + EHCI_USBSTS);
277 	if ((val & EHCI_USBSTS_HALTED) == 0) {
278 		val = readl(op_reg_base + EHCI_USBCMD);
279 		val &= ~EHCI_USBCMD_RUN;
280 		writel(val, op_reg_base + EHCI_USBCMD);
281 
282 		wait_time = 2000;
283 		delta = 100;
284 		do {
285 			writel(0x3f, op_reg_base + EHCI_USBSTS);
286 			udelay(delta);
287 			wait_time -= delta;
288 			val = readl(op_reg_base + EHCI_USBSTS);
289 			if ((val == ~(u32)0) || (val & EHCI_USBSTS_HALTED)) {
290 				break;
291 			}
292 		} while (wait_time > 0);
293 	}
294 	writel(0, op_reg_base + EHCI_USBINTR);
295 	writel(0x3f, op_reg_base + EHCI_USBSTS);
296 
297 	iounmap(base);
298 
299 	return;
300 }
301 
302 
303 
304 static void __devinit quirk_usb_early_handoff(struct pci_dev *pdev)
305 {
306 	if (pdev->class == PCI_CLASS_SERIAL_USB_UHCI)
307 		quirk_usb_handoff_uhci(pdev);
308 	else if (pdev->class == PCI_CLASS_SERIAL_USB_OHCI)
309 		quirk_usb_handoff_ohci(pdev);
310 	else if (pdev->class == PCI_CLASS_SERIAL_USB_EHCI)
311 		quirk_usb_disable_ehci(pdev);
312 }
313 DECLARE_PCI_FIXUP_FINAL(PCI_ANY_ID, PCI_ANY_ID, quirk_usb_early_handoff);
314