xref: /openbmc/linux/arch/x86/include/asm/iosf_mbi.h (revision 68198dca)
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 
59 bool 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  */
71 int 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  */
83 int 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  */
96 int 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  */
118 void iosf_mbi_punit_acquire(void);
119 
120 /**
121  * iosf_mbi_punit_release() - Release access to the P-Unit
122  */
123 void 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  */
140 int 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  */
147 int 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  */
155 int iosf_mbi_call_pmic_bus_access_notifier_chain(unsigned long val, void *v);
156 
157 #else /* CONFIG_IOSF_MBI is not enabled */
158 static inline
159 bool iosf_mbi_available(void)
160 {
161 	return false;
162 }
163 
164 static inline
165 int 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 
171 static inline
172 int 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 
178 static inline
179 int 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 
185 static inline void iosf_mbi_punit_acquire(void) {}
186 static inline void iosf_mbi_punit_release(void) {}
187 
188 static inline
189 int iosf_mbi_register_pmic_bus_access_notifier(struct notifier_block *nb)
190 {
191 	return 0;
192 }
193 
194 static inline
195 int iosf_mbi_unregister_pmic_bus_access_notifier(struct notifier_block *nb)
196 {
197 	return 0;
198 }
199 
200 static inline
201 int 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 */
209