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
25enum 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
68static 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
108static 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
151enum c_can_dev_id {
152	BOSCH_C_CAN,
153	BOSCH_D_CAN,
154};
155
156struct raminit_bits {
157	u8 start;
158	u8 done;
159};
160
161struct 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 */
172struct 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 */
180struct 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 */
187struct 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
216struct net_device *alloc_c_can_dev(int msg_obj_num);
217void free_c_can_dev(struct net_device *dev);
218int register_c_can_dev(struct net_device *dev);
219void unregister_c_can_dev(struct net_device *dev);
220
221#ifdef CONFIG_PM
222int c_can_power_up(struct net_device *dev);
223int c_can_power_down(struct net_device *dev);
224#endif
225
226extern const struct ethtool_ops c_can_ethtool_ops;
227
228static 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
233static 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
238static 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