1 /*
2 * CAN bus driver for Bosch C_CAN controller
3 *
4 * Copyright (C) 2010 ST Microelectronics
5 * Bhupesh Sharma <bhupesh.sharma@st.com>
6 *
7 * Borrowed heavily from the C_CAN driver originally written by:
8 * Copyright (C) 2007
9 * - Sascha Hauer, Marc Kleine-Budde, Pengutronix <s.hauer@pengutronix.de>
10 * - Simon Kallweit, intefo AG <simon.kallweit@intefo.ch>
11 *
12 * Bosch C_CAN controller is compliant to CAN protocol version 2.0 part A and B.
13 * Bosch C_CAN user manual can be obtained from:
14 * http://www.semiconductors.bosch.de/media/en/pdf/ipmodules_1/c_can/
15 * users_manual_c_can.pdf
16 *
17 * This file is licensed under the terms of the GNU General Public
18 * License version 2. This program is licensed "as is" without any
19 * warranty of any kind, whether express or implied.
20 */
21
22 #ifndef C_CAN_H
23 #define C_CAN_H
24
25 enum reg {
26 C_CAN_CTRL_REG = 0,
27 C_CAN_CTRL_EX_REG,
28 C_CAN_STS_REG,
29 C_CAN_ERR_CNT_REG,
30 C_CAN_BTR_REG,
31 C_CAN_INT_REG,
32 C_CAN_TEST_REG,
33 C_CAN_BRPEXT_REG,
34 C_CAN_IF1_COMREQ_REG,
35 C_CAN_IF1_COMMSK_REG,
36 C_CAN_IF1_MASK1_REG,
37 C_CAN_IF1_MASK2_REG,
38 C_CAN_IF1_ARB1_REG,
39 C_CAN_IF1_ARB2_REG,
40 C_CAN_IF1_MSGCTRL_REG,
41 C_CAN_IF1_DATA1_REG,
42 C_CAN_IF1_DATA2_REG,
43 C_CAN_IF1_DATA3_REG,
44 C_CAN_IF1_DATA4_REG,
45 C_CAN_IF2_COMREQ_REG,
46 C_CAN_IF2_COMMSK_REG,
47 C_CAN_IF2_MASK1_REG,
48 C_CAN_IF2_MASK2_REG,
49 C_CAN_IF2_ARB1_REG,
50 C_CAN_IF2_ARB2_REG,
51 C_CAN_IF2_MSGCTRL_REG,
52 C_CAN_IF2_DATA1_REG,
53 C_CAN_IF2_DATA2_REG,
54 C_CAN_IF2_DATA3_REG,
55 C_CAN_IF2_DATA4_REG,
56 C_CAN_TXRQST1_REG,
57 C_CAN_TXRQST2_REG,
58 C_CAN_NEWDAT1_REG,
59 C_CAN_NEWDAT2_REG,
60 C_CAN_INTPND1_REG,
61 C_CAN_INTPND2_REG,
62 C_CAN_INTPND3_REG,
63 C_CAN_MSGVAL1_REG,
64 C_CAN_MSGVAL2_REG,
65 C_CAN_FUNCTION_REG,
66 };
67
68 static const u16 __maybe_unused reg_map_c_can[] = {
69 [C_CAN_CTRL_REG] = 0x00,
70 [C_CAN_STS_REG] = 0x02,
71 [C_CAN_ERR_CNT_REG] = 0x04,
72 [C_CAN_BTR_REG] = 0x06,
73 [C_CAN_INT_REG] = 0x08,
74 [C_CAN_TEST_REG] = 0x0A,
75 [C_CAN_BRPEXT_REG] = 0x0C,
76 [C_CAN_IF1_COMREQ_REG] = 0x10,
77 [C_CAN_IF1_COMMSK_REG] = 0x12,
78 [C_CAN_IF1_MASK1_REG] = 0x14,
79 [C_CAN_IF1_MASK2_REG] = 0x16,
80 [C_CAN_IF1_ARB1_REG] = 0x18,
81 [C_CAN_IF1_ARB2_REG] = 0x1A,
82 [C_CAN_IF1_MSGCTRL_REG] = 0x1C,
83 [C_CAN_IF1_DATA1_REG] = 0x1E,
84 [C_CAN_IF1_DATA2_REG] = 0x20,
85 [C_CAN_IF1_DATA3_REG] = 0x22,
86 [C_CAN_IF1_DATA4_REG] = 0x24,
87 [C_CAN_IF2_COMREQ_REG] = 0x40,
88 [C_CAN_IF2_COMMSK_REG] = 0x42,
89 [C_CAN_IF2_MASK1_REG] = 0x44,
90 [C_CAN_IF2_MASK2_REG] = 0x46,
91 [C_CAN_IF2_ARB1_REG] = 0x48,
92 [C_CAN_IF2_ARB2_REG] = 0x4A,
93 [C_CAN_IF2_MSGCTRL_REG] = 0x4C,
94 [C_CAN_IF2_DATA1_REG] = 0x4E,
95 [C_CAN_IF2_DATA2_REG] = 0x50,
96 [C_CAN_IF2_DATA3_REG] = 0x52,
97 [C_CAN_IF2_DATA4_REG] = 0x54,
98 [C_CAN_TXRQST1_REG] = 0x80,
99 [C_CAN_TXRQST2_REG] = 0x82,
100 [C_CAN_NEWDAT1_REG] = 0x90,
101 [C_CAN_NEWDAT2_REG] = 0x92,
102 [C_CAN_INTPND1_REG] = 0xA0,
103 [C_CAN_INTPND2_REG] = 0xA2,
104 [C_CAN_MSGVAL1_REG] = 0xB0,
105 [C_CAN_MSGVAL2_REG] = 0xB2,
106 };
107
108 static const u16 __maybe_unused reg_map_d_can[] = {
109 [C_CAN_CTRL_REG] = 0x00,
110 [C_CAN_CTRL_EX_REG] = 0x02,
111 [C_CAN_STS_REG] = 0x04,
112 [C_CAN_ERR_CNT_REG] = 0x08,
113 [C_CAN_BTR_REG] = 0x0C,
114 [C_CAN_BRPEXT_REG] = 0x0E,
115 [C_CAN_INT_REG] = 0x10,
116 [C_CAN_TEST_REG] = 0x14,
117 [C_CAN_FUNCTION_REG] = 0x18,
118 [C_CAN_TXRQST1_REG] = 0x88,
119 [C_CAN_TXRQST2_REG] = 0x8A,
120 [C_CAN_NEWDAT1_REG] = 0x9C,
121 [C_CAN_NEWDAT2_REG] = 0x9E,
122 [C_CAN_INTPND1_REG] = 0xB0,
123 [C_CAN_INTPND2_REG] = 0xB2,
124 [C_CAN_INTPND3_REG] = 0xB4,
125 [C_CAN_MSGVAL1_REG] = 0xC4,
126 [C_CAN_MSGVAL2_REG] = 0xC6,
127 [C_CAN_IF1_COMREQ_REG] = 0x100,
128 [C_CAN_IF1_COMMSK_REG] = 0x102,
129 [C_CAN_IF1_MASK1_REG] = 0x104,
130 [C_CAN_IF1_MASK2_REG] = 0x106,
131 [C_CAN_IF1_ARB1_REG] = 0x108,
132 [C_CAN_IF1_ARB2_REG] = 0x10A,
133 [C_CAN_IF1_MSGCTRL_REG] = 0x10C,
134 [C_CAN_IF1_DATA1_REG] = 0x110,
135 [C_CAN_IF1_DATA2_REG] = 0x112,
136 [C_CAN_IF1_DATA3_REG] = 0x114,
137 [C_CAN_IF1_DATA4_REG] = 0x116,
138 [C_CAN_IF2_COMREQ_REG] = 0x120,
139 [C_CAN_IF2_COMMSK_REG] = 0x122,
140 [C_CAN_IF2_MASK1_REG] = 0x124,
141 [C_CAN_IF2_MASK2_REG] = 0x126,
142 [C_CAN_IF2_ARB1_REG] = 0x128,
143 [C_CAN_IF2_ARB2_REG] = 0x12A,
144 [C_CAN_IF2_MSGCTRL_REG] = 0x12C,
145 [C_CAN_IF2_DATA1_REG] = 0x130,
146 [C_CAN_IF2_DATA2_REG] = 0x132,
147 [C_CAN_IF2_DATA3_REG] = 0x134,
148 [C_CAN_IF2_DATA4_REG] = 0x136,
149 };
150
151 enum c_can_dev_id {
152 BOSCH_C_CAN,
153 BOSCH_D_CAN,
154 };
155
156 struct raminit_bits {
157 u8 start;
158 u8 done;
159 };
160
161 struct c_can_driver_data {
162 enum c_can_dev_id id;
163 unsigned int msg_obj_num;
164
165 /* RAMINIT register description. Optional. */
166 const struct raminit_bits *raminit_bits; /* Array of START/DONE bit positions */
167 u8 raminit_num; /* Number of CAN instances on the SoC */
168 bool raminit_pulse; /* If set, sets and clears START bit (pulse) */
169 };
170
171 /* Out of band RAMINIT register access via syscon regmap */
172 struct c_can_raminit {
173 struct regmap *syscon; /* for raminit ctrl. reg. access */
174 unsigned int reg; /* register index within syscon */
175 struct raminit_bits bits;
176 bool needs_pulse;
177 };
178
179 /* c_can tx ring structure */
180 struct c_can_tx_ring {
181 unsigned int head;
182 unsigned int tail;
183 unsigned int obj_num;
184 };
185
186 /* c_can private data structure */
187 struct c_can_priv {
188 struct can_priv can; /* must be the first member */
189 struct napi_struct napi;
190 struct net_device *dev;
191 struct device *device;
192 unsigned int msg_obj_num;
193 unsigned int msg_obj_rx_num;
194 unsigned int msg_obj_tx_num;
195 unsigned int msg_obj_rx_first;
196 unsigned int msg_obj_rx_last;
197 unsigned int msg_obj_tx_first;
198 unsigned int msg_obj_tx_last;
199 u32 msg_obj_rx_mask;
200 atomic_t sie_pending;
201 unsigned long tx_dir;
202 int last_status;
203 struct c_can_tx_ring tx;
204 u16 (*read_reg)(const struct c_can_priv *priv, enum reg index);
205 void (*write_reg)(const struct c_can_priv *priv, enum reg index, u16 val);
206 u32 (*read_reg32)(const struct c_can_priv *priv, enum reg index);
207 void (*write_reg32)(const struct c_can_priv *priv, enum reg index, u32 val);
208 void __iomem *base;
209 const u16 *regs;
210 enum c_can_dev_id type;
211 struct c_can_raminit raminit_sys; /* RAMINIT via syscon regmap */
212 void (*raminit)(const struct c_can_priv *priv, bool enable);
213 u32 comm_rcv_high;
214 };
215
216 struct net_device *alloc_c_can_dev(int msg_obj_num);
217 void free_c_can_dev(struct net_device *dev);
218 int register_c_can_dev(struct net_device *dev);
219 void unregister_c_can_dev(struct net_device *dev);
220
221 #ifdef CONFIG_PM
222 int c_can_power_up(struct net_device *dev);
223 int c_can_power_down(struct net_device *dev);
224 #endif
225
226 extern const struct ethtool_ops c_can_ethtool_ops;
227
c_can_get_tx_head(const struct c_can_tx_ring * ring)228 static inline u8 c_can_get_tx_head(const struct c_can_tx_ring *ring)
229 {
230 return ring->head & (ring->obj_num - 1);
231 }
232
c_can_get_tx_tail(const struct c_can_tx_ring * ring)233 static inline u8 c_can_get_tx_tail(const struct c_can_tx_ring *ring)
234 {
235 return ring->tail & (ring->obj_num - 1);
236 }
237
c_can_get_tx_free(const struct c_can_priv * priv,const struct c_can_tx_ring * ring)238 static inline u8 c_can_get_tx_free(const struct c_can_priv *priv,
239 const struct c_can_tx_ring *ring)
240 {
241 u8 head = c_can_get_tx_head(ring);
242 u8 tail = c_can_get_tx_tail(ring);
243
244 if (priv->type == BOSCH_D_CAN)
245 return ring->obj_num - (ring->head - ring->tail);
246
247 /* This is not a FIFO. C/D_CAN sends out the buffers
248 * prioritized. The lowest buffer number wins.
249 */
250 if (head < tail)
251 return 0;
252
253 return ring->obj_num - head;
254 }
255
256 #endif /* C_CAN_H */
257