1 // SPDX-License-Identifier: BSD-3-Clause
2 /*
3 * Copyright (c) 2020, MIPI Alliance, Inc.
4 *
5 * Author: Nicolas Pitre <[email protected]>
6 */
7
8 #include <linux/bitfield.h>
9 #include <linux/bitmap.h>
10 #include <linux/device.h>
11 #include <linux/errno.h>
12 #include <linux/i3c/master.h>
13 #include <linux/io.h>
14
15 #include "hci.h"
16 #include "dat.h"
17
18
19 /*
20 * Device Address Table Structure
21 */
22
23 #define DAT_1_AUTOCMD_HDR_CODE W1_MASK(58, 51)
24 #define DAT_1_AUTOCMD_MODE W1_MASK(50, 48)
25 #define DAT_1_AUTOCMD_VALUE W1_MASK(47, 40)
26 #define DAT_1_AUTOCMD_MASK W1_MASK(39, 32)
27 /* DAT_0_I2C_DEVICE W0_BIT_(31) */
28 #define DAT_0_DEV_NACK_RETRY_CNT W0_MASK(30, 29)
29 #define DAT_0_RING_ID W0_MASK(28, 26)
30 #define DAT_0_DYNADDR_PARITY W0_BIT_(23)
31 #define DAT_0_DYNAMIC_ADDRESS W0_MASK(22, 16)
32 #define DAT_0_TS W0_BIT_(15)
33 #define DAT_0_MR_REJECT W0_BIT_(14)
34 /* DAT_0_SIR_REJECT W0_BIT_(13) */
35 /* DAT_0_IBI_PAYLOAD W0_BIT_(12) */
36 #define DAT_0_STATIC_ADDRESS W0_MASK(6, 0)
37
38 #define dat_w0_read(i) readl(hci->DAT_regs + (i) * 8)
39 #define dat_w1_read(i) readl(hci->DAT_regs + (i) * 8 + 4)
40 #define dat_w0_write(i, v) writel(v, hci->DAT_regs + (i) * 8)
41 #define dat_w1_write(i, v) writel(v, hci->DAT_regs + (i) * 8 + 4)
42
hci_dat_v1_init(struct i3c_hci * hci)43 static int hci_dat_v1_init(struct i3c_hci *hci)
44 {
45 unsigned int dat_idx;
46
47 if (!hci->DAT_regs) {
48 dev_err(&hci->master.dev,
49 "only DAT in register space is supported at the moment\n");
50 return -EOPNOTSUPP;
51 }
52 if (hci->DAT_entry_size != 8) {
53 dev_err(&hci->master.dev,
54 "only 8-bytes DAT entries are supported at the moment\n");
55 return -EOPNOTSUPP;
56 }
57
58 if (!hci->DAT_data) {
59 /* use a bitmap for faster free slot search */
60 hci->DAT_data = bitmap_zalloc(hci->DAT_entries, GFP_KERNEL);
61 if (!hci->DAT_data)
62 return -ENOMEM;
63
64 /* clear them */
65 for (dat_idx = 0; dat_idx < hci->DAT_entries; dat_idx++) {
66 dat_w0_write(dat_idx, 0);
67 dat_w1_write(dat_idx, 0);
68 }
69 }
70
71 return 0;
72 }
73
hci_dat_v1_cleanup(struct i3c_hci * hci)74 static void hci_dat_v1_cleanup(struct i3c_hci *hci)
75 {
76 bitmap_free(hci->DAT_data);
77 hci->DAT_data = NULL;
78 }
79
hci_dat_v1_alloc_entry(struct i3c_hci * hci)80 static int hci_dat_v1_alloc_entry(struct i3c_hci *hci)
81 {
82 unsigned int dat_idx;
83 int ret;
84
85 if (!hci->DAT_data) {
86 ret = hci_dat_v1_init(hci);
87 if (ret)
88 return ret;
89 }
90 dat_idx = find_first_zero_bit(hci->DAT_data, hci->DAT_entries);
91 if (dat_idx >= hci->DAT_entries)
92 return -ENOENT;
93 __set_bit(dat_idx, hci->DAT_data);
94
95 /* default flags */
96 dat_w0_write(dat_idx, DAT_0_SIR_REJECT | DAT_0_MR_REJECT);
97
98 return dat_idx;
99 }
100
hci_dat_v1_free_entry(struct i3c_hci * hci,unsigned int dat_idx)101 static void hci_dat_v1_free_entry(struct i3c_hci *hci, unsigned int dat_idx)
102 {
103 dat_w0_write(dat_idx, 0);
104 dat_w1_write(dat_idx, 0);
105 if (hci->DAT_data)
106 __clear_bit(dat_idx, hci->DAT_data);
107 }
108
hci_dat_v1_set_dynamic_addr(struct i3c_hci * hci,unsigned int dat_idx,u8 address)109 static void hci_dat_v1_set_dynamic_addr(struct i3c_hci *hci,
110 unsigned int dat_idx, u8 address)
111 {
112 u32 dat_w0;
113
114 dat_w0 = dat_w0_read(dat_idx);
115 dat_w0 &= ~(DAT_0_DYNAMIC_ADDRESS | DAT_0_DYNADDR_PARITY);
116 dat_w0 |= FIELD_PREP(DAT_0_DYNAMIC_ADDRESS, address) |
117 (parity8(address) ? 0 : DAT_0_DYNADDR_PARITY);
118 dat_w0_write(dat_idx, dat_w0);
119 }
120
hci_dat_v1_set_static_addr(struct i3c_hci * hci,unsigned int dat_idx,u8 address)121 static void hci_dat_v1_set_static_addr(struct i3c_hci *hci,
122 unsigned int dat_idx, u8 address)
123 {
124 u32 dat_w0;
125
126 dat_w0 = dat_w0_read(dat_idx);
127 dat_w0 &= ~DAT_0_STATIC_ADDRESS;
128 dat_w0 |= FIELD_PREP(DAT_0_STATIC_ADDRESS, address);
129 dat_w0_write(dat_idx, dat_w0);
130 }
131
hci_dat_v1_set_flags(struct i3c_hci * hci,unsigned int dat_idx,u32 w0_flags,u32 w1_flags)132 static void hci_dat_v1_set_flags(struct i3c_hci *hci, unsigned int dat_idx,
133 u32 w0_flags, u32 w1_flags)
134 {
135 u32 dat_w0, dat_w1;
136
137 dat_w0 = dat_w0_read(dat_idx);
138 dat_w1 = dat_w1_read(dat_idx);
139 dat_w0 |= w0_flags;
140 dat_w1 |= w1_flags;
141 dat_w0_write(dat_idx, dat_w0);
142 dat_w1_write(dat_idx, dat_w1);
143 }
144
hci_dat_v1_clear_flags(struct i3c_hci * hci,unsigned int dat_idx,u32 w0_flags,u32 w1_flags)145 static void hci_dat_v1_clear_flags(struct i3c_hci *hci, unsigned int dat_idx,
146 u32 w0_flags, u32 w1_flags)
147 {
148 u32 dat_w0, dat_w1;
149
150 dat_w0 = dat_w0_read(dat_idx);
151 dat_w1 = dat_w1_read(dat_idx);
152 dat_w0 &= ~w0_flags;
153 dat_w1 &= ~w1_flags;
154 dat_w0_write(dat_idx, dat_w0);
155 dat_w1_write(dat_idx, dat_w1);
156 }
157
hci_dat_v1_get_index(struct i3c_hci * hci,u8 dev_addr)158 static int hci_dat_v1_get_index(struct i3c_hci *hci, u8 dev_addr)
159 {
160 unsigned int dat_idx;
161 u32 dat_w0;
162
163 for_each_set_bit(dat_idx, hci->DAT_data, hci->DAT_entries) {
164 dat_w0 = dat_w0_read(dat_idx);
165 if (FIELD_GET(DAT_0_DYNAMIC_ADDRESS, dat_w0) == dev_addr)
166 return dat_idx;
167 }
168
169 return -ENODEV;
170 }
171
172 const struct hci_dat_ops mipi_i3c_hci_dat_v1 = {
173 .init = hci_dat_v1_init,
174 .cleanup = hci_dat_v1_cleanup,
175 .alloc_entry = hci_dat_v1_alloc_entry,
176 .free_entry = hci_dat_v1_free_entry,
177 .set_dynamic_addr = hci_dat_v1_set_dynamic_addr,
178 .set_static_addr = hci_dat_v1_set_static_addr,
179 .set_flags = hci_dat_v1_set_flags,
180 .clear_flags = hci_dat_v1_clear_flags,
181 .get_index = hci_dat_v1_get_index,
182 };
183