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Linux kernel mirror (for testing)
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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Intel OnChip System Fabric MailBox access support
4 */
5
6#ifndef IOSF_MBI_SYMS_H
7#define IOSF_MBI_SYMS_H
8
9#include <linux/notifier.h>
10
11#define MBI_MCR_OFFSET 0xD0
12#define MBI_MDR_OFFSET 0xD4
13#define MBI_MCRX_OFFSET 0xD8
14
15#define MBI_RD_MASK 0xFEFFFFFF
16#define MBI_WR_MASK 0X01000000
17
18#define MBI_MASK_HI 0xFFFFFF00
19#define MBI_MASK_LO 0x000000FF
20#define MBI_ENABLE 0xF0
21
22/* IOSF SB read/write opcodes */
23#define MBI_MMIO_READ 0x00
24#define MBI_MMIO_WRITE 0x01
25#define MBI_CFG_READ 0x04
26#define MBI_CFG_WRITE 0x05
27#define MBI_CR_READ 0x06
28#define MBI_CR_WRITE 0x07
29#define MBI_REG_READ 0x10
30#define MBI_REG_WRITE 0x11
31#define MBI_ESRAM_READ 0x12
32#define MBI_ESRAM_WRITE 0x13
33
34/* Baytrail available units */
35#define BT_MBI_UNIT_AUNIT 0x00
36#define BT_MBI_UNIT_SMC 0x01
37#define BT_MBI_UNIT_CPU 0x02
38#define BT_MBI_UNIT_BUNIT 0x03
39#define BT_MBI_UNIT_PMC 0x04
40#define BT_MBI_UNIT_GFX 0x06
41#define BT_MBI_UNIT_SMI 0x0C
42#define BT_MBI_UNIT_USB 0x43
43#define BT_MBI_UNIT_SATA 0xA3
44#define BT_MBI_UNIT_PCIE 0xA6
45
46/* Quark available units */
47#define QRK_MBI_UNIT_HBA 0x00
48#define QRK_MBI_UNIT_HB 0x03
49#define QRK_MBI_UNIT_RMU 0x04
50#define QRK_MBI_UNIT_MM 0x05
51#define QRK_MBI_UNIT_SOC 0x31
52
53/* Action values for the pmic_bus_access_notifier functions */
54#define MBI_PMIC_BUS_ACCESS_BEGIN 1
55#define MBI_PMIC_BUS_ACCESS_END 2
56
57#if IS_ENABLED(CONFIG_IOSF_MBI)
58
59bool iosf_mbi_available(void);
60
61/**
62 * iosf_mbi_read() - MailBox Interface read command
63 * @port: port indicating subunit being accessed
64 * @opcode: port specific read or write opcode
65 * @offset: register address offset
66 * @mdr: register data to be read
67 *
68 * Locking is handled by spinlock - cannot sleep.
69 * Return: Nonzero on error
70 */
71int iosf_mbi_read(u8 port, u8 opcode, u32 offset, u32 *mdr);
72
73/**
74 * iosf_mbi_write() - MailBox unmasked write command
75 * @port: port indicating subunit being accessed
76 * @opcode: port specific read or write opcode
77 * @offset: register address offset
78 * @mdr: register data to be written
79 *
80 * Locking is handled by spinlock - cannot sleep.
81 * Return: Nonzero on error
82 */
83int iosf_mbi_write(u8 port, u8 opcode, u32 offset, u32 mdr);
84
85/**
86 * iosf_mbi_modify() - MailBox masked write command
87 * @port: port indicating subunit being accessed
88 * @opcode: port specific read or write opcode
89 * @offset: register address offset
90 * @mdr: register data being modified
91 * @mask: mask indicating bits in mdr to be modified
92 *
93 * Locking is handled by spinlock - cannot sleep.
94 * Return: Nonzero on error
95 */
96int iosf_mbi_modify(u8 port, u8 opcode, u32 offset, u32 mdr, u32 mask);
97
98/**
99 * iosf_mbi_punit_acquire() - Acquire access to the P-Unit
100 *
101 * One some systems the P-Unit accesses the PMIC to change various voltages
102 * through the same bus as other kernel drivers use for e.g. battery monitoring.
103 *
104 * If a driver sends requests to the P-Unit which require the P-Unit to access
105 * the PMIC bus while another driver is also accessing the PMIC bus various bad
106 * things happen.
107 *
108 * To avoid these problems this function must be called before accessing the
109 * P-Unit or the PMIC, be it through iosf_mbi* functions or through other means.
110 *
111 * Note on these systems the i2c-bus driver will request a sempahore from the
112 * P-Unit for exclusive access to the PMIC bus when i2c drivers are accessing
113 * it, but this does not appear to be sufficient, we still need to avoid making
114 * certain P-Unit requests during the access window to avoid problems.
115 *
116 * This function locks a mutex, as such it may sleep.
117 */
118void iosf_mbi_punit_acquire(void);
119
120/**
121 * iosf_mbi_punit_release() - Release access to the P-Unit
122 */
123void iosf_mbi_punit_release(void);
124
125/**
126 * iosf_mbi_register_pmic_bus_access_notifier - Register PMIC bus notifier
127 *
128 * This function can be used by drivers which may need to acquire P-Unit
129 * managed resources from interrupt context, where iosf_mbi_punit_acquire()
130 * can not be used.
131 *
132 * This function allows a driver to register a notifier to get notified (in a
133 * process context) before other drivers start accessing the PMIC bus.
134 *
135 * This allows the driver to acquire any resources, which it may need during
136 * the window the other driver is accessing the PMIC, before hand.
137 *
138 * @nb: notifier_block to register
139 */
140int iosf_mbi_register_pmic_bus_access_notifier(struct notifier_block *nb);
141
142/**
143 * iosf_mbi_register_pmic_bus_access_notifier - Unregister PMIC bus notifier
144 *
145 * @nb: notifier_block to unregister
146 */
147int iosf_mbi_unregister_pmic_bus_access_notifier(struct notifier_block *nb);
148
149/**
150 * iosf_mbi_call_pmic_bus_access_notifier_chain - Call PMIC bus notifier chain
151 *
152 * @val: action to pass into listener's notifier_call function
153 * @v: data pointer to pass into listener's notifier_call function
154 */
155int iosf_mbi_call_pmic_bus_access_notifier_chain(unsigned long val, void *v);
156
157#else /* CONFIG_IOSF_MBI is not enabled */
158static inline
159bool iosf_mbi_available(void)
160{
161 return false;
162}
163
164static inline
165int iosf_mbi_read(u8 port, u8 opcode, u32 offset, u32 *mdr)
166{
167 WARN(1, "IOSF_MBI driver not available");
168 return -EPERM;
169}
170
171static inline
172int iosf_mbi_write(u8 port, u8 opcode, u32 offset, u32 mdr)
173{
174 WARN(1, "IOSF_MBI driver not available");
175 return -EPERM;
176}
177
178static inline
179int iosf_mbi_modify(u8 port, u8 opcode, u32 offset, u32 mdr, u32 mask)
180{
181 WARN(1, "IOSF_MBI driver not available");
182 return -EPERM;
183}
184
185static inline void iosf_mbi_punit_acquire(void) {}
186static inline void iosf_mbi_punit_release(void) {}
187
188static inline
189int iosf_mbi_register_pmic_bus_access_notifier(struct notifier_block *nb)
190{
191 return 0;
192}
193
194static inline
195int iosf_mbi_unregister_pmic_bus_access_notifier(struct notifier_block *nb)
196{
197 return 0;
198}
199
200static inline
201int iosf_mbi_call_pmic_bus_access_notifier_chain(unsigned long val, void *v)
202{
203 return 0;
204}
205
206#endif /* CONFIG_IOSF_MBI */
207
208#endif /* IOSF_MBI_SYMS_H */