xref: /openbmc/linux/drivers/usb/host/xhci-ext-caps.h (revision 4cff79e9)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * xHCI host controller driver
4  *
5  * Copyright (C) 2008 Intel Corp.
6  *
7  * Author: Sarah Sharp
8  * Some code borrowed from the Linux EHCI driver.
9  */
10 /* Up to 16 ms to halt an HC */
11 #define XHCI_MAX_HALT_USEC	(16*1000)
12 /* HC not running - set to 1 when run/stop bit is cleared. */
13 #define XHCI_STS_HALT		(1<<0)
14 
15 /* HCCPARAMS offset from PCI base address */
16 #define XHCI_HCC_PARAMS_OFFSET	0x10
17 /* HCCPARAMS contains the first extended capability pointer */
18 #define XHCI_HCC_EXT_CAPS(p)	(((p)>>16)&0xffff)
19 
20 /* Command and Status registers offset from the Operational Registers address */
21 #define XHCI_CMD_OFFSET		0x00
22 #define XHCI_STS_OFFSET		0x04
23 
24 #define XHCI_MAX_EXT_CAPS		50
25 
26 /* Capability Register */
27 /* bits 7:0 - how long is the Capabilities register */
28 #define XHCI_HC_LENGTH(p)	(((p)>>00)&0x00ff)
29 
30 /* Extended capability register fields */
31 #define XHCI_EXT_CAPS_ID(p)	(((p)>>0)&0xff)
32 #define XHCI_EXT_CAPS_NEXT(p)	(((p)>>8)&0xff)
33 #define	XHCI_EXT_CAPS_VAL(p)	((p)>>16)
34 /* Extended capability IDs - ID 0 reserved */
35 #define XHCI_EXT_CAPS_LEGACY	1
36 #define XHCI_EXT_CAPS_PROTOCOL	2
37 #define XHCI_EXT_CAPS_PM	3
38 #define XHCI_EXT_CAPS_VIRT	4
39 #define XHCI_EXT_CAPS_ROUTE	5
40 /* IDs 6-9 reserved */
41 #define XHCI_EXT_CAPS_DEBUG	10
42 /* Vendor caps */
43 #define XHCI_EXT_CAPS_VENDOR_INTEL	192
44 /* USB Legacy Support Capability - section 7.1.1 */
45 #define XHCI_HC_BIOS_OWNED	(1 << 16)
46 #define XHCI_HC_OS_OWNED	(1 << 24)
47 
48 /* USB Legacy Support Capability - section 7.1.1 */
49 /* Add this offset, plus the value of xECP in HCCPARAMS to the base address */
50 #define XHCI_LEGACY_SUPPORT_OFFSET	(0x00)
51 
52 /* USB Legacy Support Control and Status Register  - section 7.1.2 */
53 /* Add this offset, plus the value of xECP in HCCPARAMS to the base address */
54 #define XHCI_LEGACY_CONTROL_OFFSET	(0x04)
55 /* bits 1:3, 5:12, and 17:19 need to be preserved; bits 21:28 should be zero */
56 #define	XHCI_LEGACY_DISABLE_SMI		((0x7 << 1) + (0xff << 5) + (0x7 << 17))
57 #define XHCI_LEGACY_SMI_EVENTS		(0x7 << 29)
58 
59 /* USB 2.0 xHCI 0.96 L1C capability - section 7.2.2.1.3.2 */
60 #define XHCI_L1C               (1 << 16)
61 
62 /* USB 2.0 xHCI 1.0 hardware LMP capability - section 7.2.2.1.3.2 */
63 #define XHCI_HLC               (1 << 19)
64 #define XHCI_BLC               (1 << 20)
65 
66 /* command register values to disable interrupts and halt the HC */
67 /* start/stop HC execution - do not write unless HC is halted*/
68 #define XHCI_CMD_RUN		(1 << 0)
69 /* Event Interrupt Enable - get irq when EINT bit is set in USBSTS register */
70 #define XHCI_CMD_EIE		(1 << 2)
71 /* Host System Error Interrupt Enable - get irq when HSEIE bit set in USBSTS */
72 #define XHCI_CMD_HSEIE		(1 << 3)
73 /* Enable Wrap Event - '1' means xHC generates an event when MFINDEX wraps. */
74 #define XHCI_CMD_EWE		(1 << 10)
75 
76 #define XHCI_IRQS		(XHCI_CMD_EIE | XHCI_CMD_HSEIE | XHCI_CMD_EWE)
77 
78 /* true: Controller Not Ready to accept doorbell or op reg writes after reset */
79 #define XHCI_STS_CNR		(1 << 11)
80 
81 #include <linux/io.h>
82 
83 /**
84  * Find the offset of the extended capabilities with capability ID id.
85  *
86  * @base	PCI MMIO registers base address.
87  * @start	address at which to start looking, (0 or HCC_PARAMS to start at
88  *		beginning of list)
89  * @id		Extended capability ID to search for, or 0 for the next
90  *		capability
91  *
92  * Returns the offset of the next matching extended capability structure.
93  * Some capabilities can occur several times, e.g., the XHCI_EXT_CAPS_PROTOCOL,
94  * and this provides a way to find them all.
95  */
96 
97 static inline int xhci_find_next_ext_cap(void __iomem *base, u32 start, int id)
98 {
99 	u32 val;
100 	u32 next;
101 	u32 offset;
102 
103 	offset = start;
104 	if (!start || start == XHCI_HCC_PARAMS_OFFSET) {
105 		val = readl(base + XHCI_HCC_PARAMS_OFFSET);
106 		if (val == ~0)
107 			return 0;
108 		offset = XHCI_HCC_EXT_CAPS(val) << 2;
109 		if (!offset)
110 			return 0;
111 	}
112 	do {
113 		val = readl(base + offset);
114 		if (val == ~0)
115 			return 0;
116 		if (offset != start && (id == 0 || XHCI_EXT_CAPS_ID(val) == id))
117 			return offset;
118 
119 		next = XHCI_EXT_CAPS_NEXT(val);
120 		offset += next << 2;
121 	} while (next);
122 
123 	return 0;
124 }
125