1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // flexcan.c - FLEXCAN CAN controller driver
4 //
5 // Copyright (c) 2005-2006 Varma Electronics Oy
6 // Copyright (c) 2009 Sascha Hauer, Pengutronix
7 // Copyright (c) 2010-2017 Pengutronix, Marc Kleine-Budde <kernel@pengutronix.de>
8 // Copyright (c) 2014 David Jander, Protonic Holland
9 //
10 // Based on code originally by Andrey Volkov <avolkov@varma-el.com>
11 
12 #include <dt-bindings/firmware/imx/rsrc.h>
13 #include <linux/bitfield.h>
14 #include <linux/can.h>
15 #include <linux/can/dev.h>
16 #include <linux/can/error.h>
17 #include <linux/clk.h>
18 #include <linux/delay.h>
19 #include <linux/firmware/imx/sci.h>
20 #include <linux/interrupt.h>
21 #include <linux/io.h>
22 #include <linux/mfd/syscon.h>
23 #include <linux/module.h>
24 #include <linux/netdevice.h>
25 #include <linux/of.h>
26 #include <linux/of_device.h>
27 #include <linux/pinctrl/consumer.h>
28 #include <linux/platform_device.h>
29 #include <linux/can/platform/flexcan.h>
30 #include <linux/pm_runtime.h>
31 #include <linux/regmap.h>
32 #include <linux/regulator/consumer.h>
33 
34 #include "flexcan.h"
35 
36 #define DRV_NAME			"flexcan"
37 
38 /* 8 for RX fifo and 2 error handling */
39 #define FLEXCAN_NAPI_WEIGHT		(8 + 2)
40 
41 /* FLEXCAN module configuration register (CANMCR) bits */
42 #define FLEXCAN_MCR_MDIS		BIT(31)
43 #define FLEXCAN_MCR_FRZ			BIT(30)
44 #define FLEXCAN_MCR_FEN			BIT(29)
45 #define FLEXCAN_MCR_HALT		BIT(28)
46 #define FLEXCAN_MCR_NOT_RDY		BIT(27)
47 #define FLEXCAN_MCR_WAK_MSK		BIT(26)
48 #define FLEXCAN_MCR_SOFTRST		BIT(25)
49 #define FLEXCAN_MCR_FRZ_ACK		BIT(24)
50 #define FLEXCAN_MCR_SUPV		BIT(23)
51 #define FLEXCAN_MCR_SLF_WAK		BIT(22)
52 #define FLEXCAN_MCR_WRN_EN		BIT(21)
53 #define FLEXCAN_MCR_LPM_ACK		BIT(20)
54 #define FLEXCAN_MCR_WAK_SRC		BIT(19)
55 #define FLEXCAN_MCR_DOZE		BIT(18)
56 #define FLEXCAN_MCR_SRX_DIS		BIT(17)
57 #define FLEXCAN_MCR_IRMQ		BIT(16)
58 #define FLEXCAN_MCR_LPRIO_EN		BIT(13)
59 #define FLEXCAN_MCR_AEN			BIT(12)
60 #define FLEXCAN_MCR_FDEN		BIT(11)
61 /* MCR_MAXMB: maximum used MBs is MAXMB + 1 */
62 #define FLEXCAN_MCR_MAXMB(x)		((x) & 0x7f)
63 #define FLEXCAN_MCR_IDAM_A		(0x0 << 8)
64 #define FLEXCAN_MCR_IDAM_B		(0x1 << 8)
65 #define FLEXCAN_MCR_IDAM_C		(0x2 << 8)
66 #define FLEXCAN_MCR_IDAM_D		(0x3 << 8)
67 
68 /* FLEXCAN control register (CANCTRL) bits */
69 #define FLEXCAN_CTRL_PRESDIV(x)		(((x) & 0xff) << 24)
70 #define FLEXCAN_CTRL_RJW(x)		(((x) & 0x03) << 22)
71 #define FLEXCAN_CTRL_PSEG1(x)		(((x) & 0x07) << 19)
72 #define FLEXCAN_CTRL_PSEG2(x)		(((x) & 0x07) << 16)
73 #define FLEXCAN_CTRL_BOFF_MSK		BIT(15)
74 #define FLEXCAN_CTRL_ERR_MSK		BIT(14)
75 #define FLEXCAN_CTRL_CLK_SRC		BIT(13)
76 #define FLEXCAN_CTRL_LPB		BIT(12)
77 #define FLEXCAN_CTRL_TWRN_MSK		BIT(11)
78 #define FLEXCAN_CTRL_RWRN_MSK		BIT(10)
79 #define FLEXCAN_CTRL_SMP		BIT(7)
80 #define FLEXCAN_CTRL_BOFF_REC		BIT(6)
81 #define FLEXCAN_CTRL_TSYN		BIT(5)
82 #define FLEXCAN_CTRL_LBUF		BIT(4)
83 #define FLEXCAN_CTRL_LOM		BIT(3)
84 #define FLEXCAN_CTRL_PROPSEG(x)		((x) & 0x07)
85 #define FLEXCAN_CTRL_ERR_BUS		(FLEXCAN_CTRL_ERR_MSK)
86 #define FLEXCAN_CTRL_ERR_STATE \
87 	(FLEXCAN_CTRL_TWRN_MSK | FLEXCAN_CTRL_RWRN_MSK | \
88 	 FLEXCAN_CTRL_BOFF_MSK)
89 #define FLEXCAN_CTRL_ERR_ALL \
90 	(FLEXCAN_CTRL_ERR_BUS | FLEXCAN_CTRL_ERR_STATE)
91 
92 /* FLEXCAN control register 2 (CTRL2) bits */
93 #define FLEXCAN_CTRL2_ECRWRE		BIT(29)
94 #define FLEXCAN_CTRL2_WRMFRZ		BIT(28)
95 #define FLEXCAN_CTRL2_RFFN(x)		(((x) & 0x0f) << 24)
96 #define FLEXCAN_CTRL2_TASD(x)		(((x) & 0x1f) << 19)
97 #define FLEXCAN_CTRL2_MRP		BIT(18)
98 #define FLEXCAN_CTRL2_RRS		BIT(17)
99 #define FLEXCAN_CTRL2_EACEN		BIT(16)
100 #define FLEXCAN_CTRL2_ISOCANFDEN	BIT(12)
101 
102 /* FLEXCAN memory error control register (MECR) bits */
103 #define FLEXCAN_MECR_ECRWRDIS		BIT(31)
104 #define FLEXCAN_MECR_HANCEI_MSK		BIT(19)
105 #define FLEXCAN_MECR_FANCEI_MSK		BIT(18)
106 #define FLEXCAN_MECR_CEI_MSK		BIT(16)
107 #define FLEXCAN_MECR_HAERRIE		BIT(15)
108 #define FLEXCAN_MECR_FAERRIE		BIT(14)
109 #define FLEXCAN_MECR_EXTERRIE		BIT(13)
110 #define FLEXCAN_MECR_RERRDIS		BIT(9)
111 #define FLEXCAN_MECR_ECCDIS		BIT(8)
112 #define FLEXCAN_MECR_NCEFAFRZ		BIT(7)
113 
114 /* FLEXCAN error and status register (ESR) bits */
115 #define FLEXCAN_ESR_TWRN_INT		BIT(17)
116 #define FLEXCAN_ESR_RWRN_INT		BIT(16)
117 #define FLEXCAN_ESR_BIT1_ERR		BIT(15)
118 #define FLEXCAN_ESR_BIT0_ERR		BIT(14)
119 #define FLEXCAN_ESR_ACK_ERR		BIT(13)
120 #define FLEXCAN_ESR_CRC_ERR		BIT(12)
121 #define FLEXCAN_ESR_FRM_ERR		BIT(11)
122 #define FLEXCAN_ESR_STF_ERR		BIT(10)
123 #define FLEXCAN_ESR_TX_WRN		BIT(9)
124 #define FLEXCAN_ESR_RX_WRN		BIT(8)
125 #define FLEXCAN_ESR_IDLE		BIT(7)
126 #define FLEXCAN_ESR_TXRX		BIT(6)
127 #define FLEXCAN_EST_FLT_CONF_SHIFT	(4)
128 #define FLEXCAN_ESR_FLT_CONF_MASK	(0x3 << FLEXCAN_EST_FLT_CONF_SHIFT)
129 #define FLEXCAN_ESR_FLT_CONF_ACTIVE	(0x0 << FLEXCAN_EST_FLT_CONF_SHIFT)
130 #define FLEXCAN_ESR_FLT_CONF_PASSIVE	(0x1 << FLEXCAN_EST_FLT_CONF_SHIFT)
131 #define FLEXCAN_ESR_BOFF_INT		BIT(2)
132 #define FLEXCAN_ESR_ERR_INT		BIT(1)
133 #define FLEXCAN_ESR_WAK_INT		BIT(0)
134 #define FLEXCAN_ESR_ERR_BUS \
135 	(FLEXCAN_ESR_BIT1_ERR | FLEXCAN_ESR_BIT0_ERR | \
136 	 FLEXCAN_ESR_ACK_ERR | FLEXCAN_ESR_CRC_ERR | \
137 	 FLEXCAN_ESR_FRM_ERR | FLEXCAN_ESR_STF_ERR)
138 #define FLEXCAN_ESR_ERR_STATE \
139 	(FLEXCAN_ESR_TWRN_INT | FLEXCAN_ESR_RWRN_INT | FLEXCAN_ESR_BOFF_INT)
140 #define FLEXCAN_ESR_ERR_ALL \
141 	(FLEXCAN_ESR_ERR_BUS | FLEXCAN_ESR_ERR_STATE)
142 #define FLEXCAN_ESR_ALL_INT \
143 	(FLEXCAN_ESR_TWRN_INT | FLEXCAN_ESR_RWRN_INT | \
144 	 FLEXCAN_ESR_BOFF_INT | FLEXCAN_ESR_ERR_INT)
145 
146 /* FLEXCAN Bit Timing register (CBT) bits */
147 #define FLEXCAN_CBT_BTF			BIT(31)
148 #define FLEXCAN_CBT_EPRESDIV_MASK	GENMASK(30, 21)
149 #define FLEXCAN_CBT_ERJW_MASK		GENMASK(20, 16)
150 #define FLEXCAN_CBT_EPROPSEG_MASK	GENMASK(15, 10)
151 #define FLEXCAN_CBT_EPSEG1_MASK		GENMASK(9, 5)
152 #define FLEXCAN_CBT_EPSEG2_MASK		GENMASK(4, 0)
153 
154 /* FLEXCAN FD control register (FDCTRL) bits */
155 #define FLEXCAN_FDCTRL_FDRATE		BIT(31)
156 #define FLEXCAN_FDCTRL_MBDSR1		GENMASK(20, 19)
157 #define FLEXCAN_FDCTRL_MBDSR0		GENMASK(17, 16)
158 #define FLEXCAN_FDCTRL_MBDSR_8		0x0
159 #define FLEXCAN_FDCTRL_MBDSR_12		0x1
160 #define FLEXCAN_FDCTRL_MBDSR_32		0x2
161 #define FLEXCAN_FDCTRL_MBDSR_64		0x3
162 #define FLEXCAN_FDCTRL_TDCEN		BIT(15)
163 #define FLEXCAN_FDCTRL_TDCFAIL		BIT(14)
164 #define FLEXCAN_FDCTRL_TDCOFF		GENMASK(12, 8)
165 #define FLEXCAN_FDCTRL_TDCVAL		GENMASK(5, 0)
166 
167 /* FLEXCAN FD Bit Timing register (FDCBT) bits */
168 #define FLEXCAN_FDCBT_FPRESDIV_MASK	GENMASK(29, 20)
169 #define FLEXCAN_FDCBT_FRJW_MASK		GENMASK(18, 16)
170 #define FLEXCAN_FDCBT_FPROPSEG_MASK	GENMASK(14, 10)
171 #define FLEXCAN_FDCBT_FPSEG1_MASK	GENMASK(7, 5)
172 #define FLEXCAN_FDCBT_FPSEG2_MASK	GENMASK(2, 0)
173 
174 /* FLEXCAN interrupt flag register (IFLAG) bits */
175 /* Errata ERR005829 step7: Reserve first valid MB */
176 #define FLEXCAN_TX_MB_RESERVED_RX_FIFO	8
177 #define FLEXCAN_TX_MB_RESERVED_RX_MAILBOX	0
178 #define FLEXCAN_RX_MB_RX_MAILBOX_FIRST	(FLEXCAN_TX_MB_RESERVED_RX_MAILBOX + 1)
179 #define FLEXCAN_IFLAG_MB(x)		BIT_ULL(x)
180 #define FLEXCAN_IFLAG_RX_FIFO_OVERFLOW	BIT(7)
181 #define FLEXCAN_IFLAG_RX_FIFO_WARN	BIT(6)
182 #define FLEXCAN_IFLAG_RX_FIFO_AVAILABLE	BIT(5)
183 
184 /* FLEXCAN message buffers */
185 #define FLEXCAN_MB_CODE_MASK		(0xf << 24)
186 #define FLEXCAN_MB_CODE_RX_BUSY_BIT	(0x1 << 24)
187 #define FLEXCAN_MB_CODE_RX_INACTIVE	(0x0 << 24)
188 #define FLEXCAN_MB_CODE_RX_EMPTY	(0x4 << 24)
189 #define FLEXCAN_MB_CODE_RX_FULL		(0x2 << 24)
190 #define FLEXCAN_MB_CODE_RX_OVERRUN	(0x6 << 24)
191 #define FLEXCAN_MB_CODE_RX_RANSWER	(0xa << 24)
192 
193 #define FLEXCAN_MB_CODE_TX_INACTIVE	(0x8 << 24)
194 #define FLEXCAN_MB_CODE_TX_ABORT	(0x9 << 24)
195 #define FLEXCAN_MB_CODE_TX_DATA		(0xc << 24)
196 #define FLEXCAN_MB_CODE_TX_TANSWER	(0xe << 24)
197 
198 #define FLEXCAN_MB_CNT_EDL		BIT(31)
199 #define FLEXCAN_MB_CNT_BRS		BIT(30)
200 #define FLEXCAN_MB_CNT_ESI		BIT(29)
201 #define FLEXCAN_MB_CNT_SRR		BIT(22)
202 #define FLEXCAN_MB_CNT_IDE		BIT(21)
203 #define FLEXCAN_MB_CNT_RTR		BIT(20)
204 #define FLEXCAN_MB_CNT_LENGTH(x)	(((x) & 0xf) << 16)
205 #define FLEXCAN_MB_CNT_TIMESTAMP(x)	((x) & 0xffff)
206 
207 #define FLEXCAN_TIMEOUT_US		(250)
208 
209 /* Structure of the message buffer */
210 struct flexcan_mb {
211 	u32 can_ctrl;
212 	u32 can_id;
213 	u32 data[];
214 };
215 
216 /* Structure of the hardware registers */
217 struct flexcan_regs {
218 	u32 mcr;		/* 0x00 */
219 	u32 ctrl;		/* 0x04 - Not affected by Soft Reset */
220 	u32 timer;		/* 0x08 */
221 	u32 tcr;		/* 0x0c */
222 	u32 rxgmask;		/* 0x10 - Not affected by Soft Reset */
223 	u32 rx14mask;		/* 0x14 - Not affected by Soft Reset */
224 	u32 rx15mask;		/* 0x18 - Not affected by Soft Reset */
225 	u32 ecr;		/* 0x1c */
226 	u32 esr;		/* 0x20 */
227 	u32 imask2;		/* 0x24 */
228 	u32 imask1;		/* 0x28 */
229 	u32 iflag2;		/* 0x2c */
230 	u32 iflag1;		/* 0x30 */
231 	union {			/* 0x34 */
232 		u32 gfwr_mx28;	/* MX28, MX53 */
233 		u32 ctrl2;	/* MX6, VF610 - Not affected by Soft Reset */
234 	};
235 	u32 esr2;		/* 0x38 */
236 	u32 imeur;		/* 0x3c */
237 	u32 lrfr;		/* 0x40 */
238 	u32 crcr;		/* 0x44 */
239 	u32 rxfgmask;		/* 0x48 */
240 	u32 rxfir;		/* 0x4c - Not affected by Soft Reset */
241 	u32 cbt;		/* 0x50 - Not affected by Soft Reset */
242 	u32 _reserved2;		/* 0x54 */
243 	u32 dbg1;		/* 0x58 */
244 	u32 dbg2;		/* 0x5c */
245 	u32 _reserved3[8];	/* 0x60 */
246 	struct_group(init,
247 		u8 mb[2][512];		/* 0x80 - Not affected by Soft Reset */
248 		/* FIFO-mode:
249 		 *			MB
250 		 * 0x080...0x08f	0	RX message buffer
251 		 * 0x090...0x0df	1-5	reserved
252 		 * 0x0e0...0x0ff	6-7	8 entry ID table
253 		 *				(mx25, mx28, mx35, mx53)
254 		 * 0x0e0...0x2df	6-7..37	8..128 entry ID table
255 		 *				size conf'ed via ctrl2::RFFN
256 		 *				(mx6, vf610)
257 		 */
258 		u32 _reserved4[256];	/* 0x480 */
259 		u32 rximr[64];		/* 0x880 - Not affected by Soft Reset */
260 		u32 _reserved5[24];	/* 0x980 */
261 		u32 gfwr_mx6;		/* 0x9e0 - MX6 */
262 		u32 _reserved6[39];	/* 0x9e4 */
263 		u32 _rxfir[6];		/* 0xa80 */
264 		u32 _reserved8[2];	/* 0xa98 */
265 		u32 _rxmgmask;		/* 0xaa0 */
266 		u32 _rxfgmask;		/* 0xaa4 */
267 		u32 _rx14mask;		/* 0xaa8 */
268 		u32 _rx15mask;		/* 0xaac */
269 		u32 tx_smb[4];		/* 0xab0 */
270 		u32 rx_smb0[4];		/* 0xac0 */
271 		u32 rx_smb1[4];		/* 0xad0 */
272 	);
273 	u32 mecr;		/* 0xae0 */
274 	u32 erriar;		/* 0xae4 */
275 	u32 erridpr;		/* 0xae8 */
276 	u32 errippr;		/* 0xaec */
277 	u32 rerrar;		/* 0xaf0 */
278 	u32 rerrdr;		/* 0xaf4 */
279 	u32 rerrsynr;		/* 0xaf8 */
280 	u32 errsr;		/* 0xafc */
281 	u32 _reserved7[64];	/* 0xb00 */
282 	u32 fdctrl;		/* 0xc00 - Not affected by Soft Reset */
283 	u32 fdcbt;		/* 0xc04 - Not affected by Soft Reset */
284 	u32 fdcrc;		/* 0xc08 */
285 	u32 _reserved9[199];	/* 0xc0c */
286 	struct_group(init_fd,
287 		u32 tx_smb_fd[18];	/* 0xf28 */
288 		u32 rx_smb0_fd[18];	/* 0xf70 */
289 		u32 rx_smb1_fd[18];	/* 0xfb8 */
290 	);
291 };
292 
293 static_assert(sizeof(struct flexcan_regs) ==  0x4 * 18 + 0xfb8);
294 
295 static const struct flexcan_devtype_data fsl_mcf5441x_devtype_data = {
296 	.quirks = FLEXCAN_QUIRK_BROKEN_PERR_STATE |
297 		FLEXCAN_QUIRK_NR_IRQ_3 | FLEXCAN_QUIRK_NR_MB_16 |
298 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
299 		FLEXCAN_QUIRK_SUPPORT_RX_FIFO,
300 };
301 
302 static const struct flexcan_devtype_data fsl_p1010_devtype_data = {
303 	.quirks = FLEXCAN_QUIRK_BROKEN_WERR_STATE |
304 		FLEXCAN_QUIRK_BROKEN_PERR_STATE |
305 		FLEXCAN_QUIRK_DEFAULT_BIG_ENDIAN |
306 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
307 		FLEXCAN_QUIRK_SUPPORT_RX_FIFO,
308 };
309 
310 static const struct flexcan_devtype_data fsl_imx25_devtype_data = {
311 	.quirks = FLEXCAN_QUIRK_BROKEN_WERR_STATE |
312 		FLEXCAN_QUIRK_BROKEN_PERR_STATE |
313 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
314 		FLEXCAN_QUIRK_SUPPORT_RX_FIFO,
315 };
316 
317 static const struct flexcan_devtype_data fsl_imx28_devtype_data = {
318 	.quirks = FLEXCAN_QUIRK_BROKEN_PERR_STATE |
319 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
320 		FLEXCAN_QUIRK_SUPPORT_RX_FIFO,
321 };
322 
323 static const struct flexcan_devtype_data fsl_imx6q_devtype_data = {
324 	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
325 		FLEXCAN_QUIRK_USE_RX_MAILBOX | FLEXCAN_QUIRK_BROKEN_PERR_STATE |
326 		FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR |
327 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
328 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR,
329 };
330 
331 static const struct flexcan_devtype_data fsl_imx8qm_devtype_data = {
332 	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
333 		FLEXCAN_QUIRK_USE_RX_MAILBOX | FLEXCAN_QUIRK_BROKEN_PERR_STATE |
334 		FLEXCAN_QUIRK_SUPPORT_FD | FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW |
335 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
336 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR,
337 };
338 
339 static struct flexcan_devtype_data fsl_imx8mp_devtype_data = {
340 	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
341 		FLEXCAN_QUIRK_DISABLE_MECR | FLEXCAN_QUIRK_USE_RX_MAILBOX |
342 		FLEXCAN_QUIRK_BROKEN_PERR_STATE | FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR |
343 		FLEXCAN_QUIRK_SUPPORT_FD | FLEXCAN_QUIRK_SUPPORT_ECC |
344 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
345 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR,
346 };
347 
348 static struct flexcan_devtype_data fsl_imx93_devtype_data = {
349 	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
350 		FLEXCAN_QUIRK_DISABLE_MECR | FLEXCAN_QUIRK_USE_RX_MAILBOX |
351 		FLEXCAN_QUIRK_BROKEN_PERR_STATE | FLEXCAN_QUIRK_AUTO_STOP_MODE |
352 		FLEXCAN_QUIRK_SUPPORT_FD | FLEXCAN_QUIRK_SUPPORT_ECC |
353 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
354 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR,
355 };
356 
357 static const struct flexcan_devtype_data fsl_vf610_devtype_data = {
358 	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
359 		FLEXCAN_QUIRK_DISABLE_MECR | FLEXCAN_QUIRK_USE_RX_MAILBOX |
360 		FLEXCAN_QUIRK_BROKEN_PERR_STATE | FLEXCAN_QUIRK_SUPPORT_ECC |
361 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
362 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR,
363 };
364 
365 static const struct flexcan_devtype_data fsl_ls1021a_r2_devtype_data = {
366 	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
367 		FLEXCAN_QUIRK_BROKEN_PERR_STATE | FLEXCAN_QUIRK_USE_RX_MAILBOX |
368 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
369 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR,
370 };
371 
372 static const struct flexcan_devtype_data fsl_lx2160a_r1_devtype_data = {
373 	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
374 		FLEXCAN_QUIRK_DISABLE_MECR | FLEXCAN_QUIRK_BROKEN_PERR_STATE |
375 		FLEXCAN_QUIRK_USE_RX_MAILBOX | FLEXCAN_QUIRK_SUPPORT_FD |
376 		FLEXCAN_QUIRK_SUPPORT_ECC |
377 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
378 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR,
379 };
380 
381 static const struct can_bittiming_const flexcan_bittiming_const = {
382 	.name = DRV_NAME,
383 	.tseg1_min = 4,
384 	.tseg1_max = 16,
385 	.tseg2_min = 2,
386 	.tseg2_max = 8,
387 	.sjw_max = 4,
388 	.brp_min = 1,
389 	.brp_max = 256,
390 	.brp_inc = 1,
391 };
392 
393 static const struct can_bittiming_const flexcan_fd_bittiming_const = {
394 	.name = DRV_NAME,
395 	.tseg1_min = 2,
396 	.tseg1_max = 96,
397 	.tseg2_min = 2,
398 	.tseg2_max = 32,
399 	.sjw_max = 16,
400 	.brp_min = 1,
401 	.brp_max = 1024,
402 	.brp_inc = 1,
403 };
404 
405 static const struct can_bittiming_const flexcan_fd_data_bittiming_const = {
406 	.name = DRV_NAME,
407 	.tseg1_min = 2,
408 	.tseg1_max = 39,
409 	.tseg2_min = 2,
410 	.tseg2_max = 8,
411 	.sjw_max = 4,
412 	.brp_min = 1,
413 	.brp_max = 1024,
414 	.brp_inc = 1,
415 };
416 
417 /* FlexCAN module is essentially modelled as a little-endian IP in most
418  * SoCs, i.e the registers as well as the message buffer areas are
419  * implemented in a little-endian fashion.
420  *
421  * However there are some SoCs (e.g. LS1021A) which implement the FlexCAN
422  * module in a big-endian fashion (i.e the registers as well as the
423  * message buffer areas are implemented in a big-endian way).
424  *
425  * In addition, the FlexCAN module can be found on SoCs having ARM or
426  * PPC cores. So, we need to abstract off the register read/write
427  * functions, ensuring that these cater to all the combinations of module
428  * endianness and underlying CPU endianness.
429  */
430 static inline u32 flexcan_read_be(void __iomem *addr)
431 {
432 	return ioread32be(addr);
433 }
434 
435 static inline void flexcan_write_be(u32 val, void __iomem *addr)
436 {
437 	iowrite32be(val, addr);
438 }
439 
440 static inline u32 flexcan_read_le(void __iomem *addr)
441 {
442 	return ioread32(addr);
443 }
444 
445 static inline void flexcan_write_le(u32 val, void __iomem *addr)
446 {
447 	iowrite32(val, addr);
448 }
449 
450 static struct flexcan_mb __iomem *flexcan_get_mb(const struct flexcan_priv *priv,
451 						 u8 mb_index)
452 {
453 	u8 bank_size;
454 	bool bank;
455 
456 	if (WARN_ON(mb_index >= priv->mb_count))
457 		return NULL;
458 
459 	bank_size = sizeof(priv->regs->mb[0]) / priv->mb_size;
460 
461 	bank = mb_index >= bank_size;
462 	if (bank)
463 		mb_index -= bank_size;
464 
465 	return (struct flexcan_mb __iomem *)
466 		(&priv->regs->mb[bank][priv->mb_size * mb_index]);
467 }
468 
469 static int flexcan_low_power_enter_ack(struct flexcan_priv *priv)
470 {
471 	struct flexcan_regs __iomem *regs = priv->regs;
472 	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
473 
474 	while (timeout-- && !(priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
475 		udelay(10);
476 
477 	if (!(priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
478 		return -ETIMEDOUT;
479 
480 	return 0;
481 }
482 
483 static int flexcan_low_power_exit_ack(struct flexcan_priv *priv)
484 {
485 	struct flexcan_regs __iomem *regs = priv->regs;
486 	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
487 
488 	while (timeout-- && (priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
489 		udelay(10);
490 
491 	if (priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK)
492 		return -ETIMEDOUT;
493 
494 	return 0;
495 }
496 
497 static void flexcan_enable_wakeup_irq(struct flexcan_priv *priv, bool enable)
498 {
499 	struct flexcan_regs __iomem *regs = priv->regs;
500 	u32 reg_mcr;
501 
502 	reg_mcr = priv->read(&regs->mcr);
503 
504 	if (enable)
505 		reg_mcr |= FLEXCAN_MCR_WAK_MSK;
506 	else
507 		reg_mcr &= ~FLEXCAN_MCR_WAK_MSK;
508 
509 	priv->write(reg_mcr, &regs->mcr);
510 }
511 
512 static int flexcan_stop_mode_enable_scfw(struct flexcan_priv *priv, bool enabled)
513 {
514 	u8 idx = priv->scu_idx;
515 	u32 rsrc_id, val;
516 
517 	rsrc_id = IMX_SC_R_CAN(idx);
518 
519 	if (enabled)
520 		val = 1;
521 	else
522 		val = 0;
523 
524 	/* stop mode request via scu firmware */
525 	return imx_sc_misc_set_control(priv->sc_ipc_handle, rsrc_id,
526 				       IMX_SC_C_IPG_STOP, val);
527 }
528 
529 static inline int flexcan_enter_stop_mode(struct flexcan_priv *priv)
530 {
531 	struct flexcan_regs __iomem *regs = priv->regs;
532 	u32 reg_mcr;
533 	int ret;
534 
535 	reg_mcr = priv->read(&regs->mcr);
536 	reg_mcr |= FLEXCAN_MCR_SLF_WAK;
537 	priv->write(reg_mcr, &regs->mcr);
538 
539 	/* enable stop request */
540 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW) {
541 		ret = flexcan_stop_mode_enable_scfw(priv, true);
542 		if (ret < 0)
543 			return ret;
544 	} else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR) {
545 		regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr,
546 				   1 << priv->stm.req_bit, 1 << priv->stm.req_bit);
547 	} else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_AUTO_STOP_MODE) {
548 		/* For the auto stop mode, software do nothing, hardware will cover
549 		 * all the operation automatically after system go into low power mode.
550 		 */
551 		return 0;
552 	}
553 
554 	return flexcan_low_power_enter_ack(priv);
555 }
556 
557 static inline int flexcan_exit_stop_mode(struct flexcan_priv *priv)
558 {
559 	struct flexcan_regs __iomem *regs = priv->regs;
560 	u32 reg_mcr;
561 	int ret;
562 
563 	/* remove stop request */
564 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW) {
565 		ret = flexcan_stop_mode_enable_scfw(priv, false);
566 		if (ret < 0)
567 			return ret;
568 	} else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR) {
569 		regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr,
570 				   1 << priv->stm.req_bit, 0);
571 	}
572 
573 	reg_mcr = priv->read(&regs->mcr);
574 	reg_mcr &= ~FLEXCAN_MCR_SLF_WAK;
575 	priv->write(reg_mcr, &regs->mcr);
576 
577 	/* For the auto stop mode, hardware will exist stop mode
578 	 * automatically after system go out of low power mode.
579 	 */
580 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_AUTO_STOP_MODE)
581 		return 0;
582 
583 	return flexcan_low_power_exit_ack(priv);
584 }
585 
586 static inline void flexcan_error_irq_enable(const struct flexcan_priv *priv)
587 {
588 	struct flexcan_regs __iomem *regs = priv->regs;
589 	u32 reg_ctrl = (priv->reg_ctrl_default | FLEXCAN_CTRL_ERR_MSK);
590 
591 	priv->write(reg_ctrl, &regs->ctrl);
592 }
593 
594 static inline void flexcan_error_irq_disable(const struct flexcan_priv *priv)
595 {
596 	struct flexcan_regs __iomem *regs = priv->regs;
597 	u32 reg_ctrl = (priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_MSK);
598 
599 	priv->write(reg_ctrl, &regs->ctrl);
600 }
601 
602 static int flexcan_clks_enable(const struct flexcan_priv *priv)
603 {
604 	int err = 0;
605 
606 	if (priv->clk_ipg) {
607 		err = clk_prepare_enable(priv->clk_ipg);
608 		if (err)
609 			return err;
610 	}
611 
612 	if (priv->clk_per) {
613 		err = clk_prepare_enable(priv->clk_per);
614 		if (err)
615 			clk_disable_unprepare(priv->clk_ipg);
616 	}
617 
618 	return err;
619 }
620 
621 static void flexcan_clks_disable(const struct flexcan_priv *priv)
622 {
623 	clk_disable_unprepare(priv->clk_per);
624 	clk_disable_unprepare(priv->clk_ipg);
625 }
626 
627 static inline int flexcan_transceiver_enable(const struct flexcan_priv *priv)
628 {
629 	if (!priv->reg_xceiver)
630 		return 0;
631 
632 	return regulator_enable(priv->reg_xceiver);
633 }
634 
635 static inline int flexcan_transceiver_disable(const struct flexcan_priv *priv)
636 {
637 	if (!priv->reg_xceiver)
638 		return 0;
639 
640 	return regulator_disable(priv->reg_xceiver);
641 }
642 
643 static int flexcan_chip_enable(struct flexcan_priv *priv)
644 {
645 	struct flexcan_regs __iomem *regs = priv->regs;
646 	u32 reg;
647 
648 	reg = priv->read(&regs->mcr);
649 	reg &= ~FLEXCAN_MCR_MDIS;
650 	priv->write(reg, &regs->mcr);
651 
652 	return flexcan_low_power_exit_ack(priv);
653 }
654 
655 static int flexcan_chip_disable(struct flexcan_priv *priv)
656 {
657 	struct flexcan_regs __iomem *regs = priv->regs;
658 	u32 reg;
659 
660 	reg = priv->read(&regs->mcr);
661 	reg |= FLEXCAN_MCR_MDIS;
662 	priv->write(reg, &regs->mcr);
663 
664 	return flexcan_low_power_enter_ack(priv);
665 }
666 
667 static int flexcan_chip_freeze(struct flexcan_priv *priv)
668 {
669 	struct flexcan_regs __iomem *regs = priv->regs;
670 	unsigned int timeout;
671 	u32 bitrate = priv->can.bittiming.bitrate;
672 	u32 reg;
673 
674 	if (bitrate)
675 		timeout = 1000 * 1000 * 10 / bitrate;
676 	else
677 		timeout = FLEXCAN_TIMEOUT_US / 10;
678 
679 	reg = priv->read(&regs->mcr);
680 	reg |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_HALT;
681 	priv->write(reg, &regs->mcr);
682 
683 	while (timeout-- && !(priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
684 		udelay(100);
685 
686 	if (!(priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
687 		return -ETIMEDOUT;
688 
689 	return 0;
690 }
691 
692 static int flexcan_chip_unfreeze(struct flexcan_priv *priv)
693 {
694 	struct flexcan_regs __iomem *regs = priv->regs;
695 	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
696 	u32 reg;
697 
698 	reg = priv->read(&regs->mcr);
699 	reg &= ~FLEXCAN_MCR_HALT;
700 	priv->write(reg, &regs->mcr);
701 
702 	while (timeout-- && (priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
703 		udelay(10);
704 
705 	if (priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK)
706 		return -ETIMEDOUT;
707 
708 	return 0;
709 }
710 
711 static int flexcan_chip_softreset(struct flexcan_priv *priv)
712 {
713 	struct flexcan_regs __iomem *regs = priv->regs;
714 	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
715 
716 	priv->write(FLEXCAN_MCR_SOFTRST, &regs->mcr);
717 	while (timeout-- && (priv->read(&regs->mcr) & FLEXCAN_MCR_SOFTRST))
718 		udelay(10);
719 
720 	if (priv->read(&regs->mcr) & FLEXCAN_MCR_SOFTRST)
721 		return -ETIMEDOUT;
722 
723 	return 0;
724 }
725 
726 static int __flexcan_get_berr_counter(const struct net_device *dev,
727 				      struct can_berr_counter *bec)
728 {
729 	const struct flexcan_priv *priv = netdev_priv(dev);
730 	struct flexcan_regs __iomem *regs = priv->regs;
731 	u32 reg = priv->read(&regs->ecr);
732 
733 	bec->txerr = (reg >> 0) & 0xff;
734 	bec->rxerr = (reg >> 8) & 0xff;
735 
736 	return 0;
737 }
738 
739 static int flexcan_get_berr_counter(const struct net_device *dev,
740 				    struct can_berr_counter *bec)
741 {
742 	const struct flexcan_priv *priv = netdev_priv(dev);
743 	int err;
744 
745 	err = pm_runtime_resume_and_get(priv->dev);
746 	if (err < 0)
747 		return err;
748 
749 	err = __flexcan_get_berr_counter(dev, bec);
750 
751 	pm_runtime_put(priv->dev);
752 
753 	return err;
754 }
755 
756 static netdev_tx_t flexcan_start_xmit(struct sk_buff *skb, struct net_device *dev)
757 {
758 	const struct flexcan_priv *priv = netdev_priv(dev);
759 	struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
760 	u32 can_id;
761 	u32 data;
762 	u32 ctrl = FLEXCAN_MB_CODE_TX_DATA | ((can_fd_len2dlc(cfd->len)) << 16);
763 	int i;
764 
765 	if (can_dev_dropped_skb(dev, skb))
766 		return NETDEV_TX_OK;
767 
768 	netif_stop_queue(dev);
769 
770 	if (cfd->can_id & CAN_EFF_FLAG) {
771 		can_id = cfd->can_id & CAN_EFF_MASK;
772 		ctrl |= FLEXCAN_MB_CNT_IDE | FLEXCAN_MB_CNT_SRR;
773 	} else {
774 		can_id = (cfd->can_id & CAN_SFF_MASK) << 18;
775 	}
776 
777 	if (cfd->can_id & CAN_RTR_FLAG)
778 		ctrl |= FLEXCAN_MB_CNT_RTR;
779 
780 	if (can_is_canfd_skb(skb)) {
781 		ctrl |= FLEXCAN_MB_CNT_EDL;
782 
783 		if (cfd->flags & CANFD_BRS)
784 			ctrl |= FLEXCAN_MB_CNT_BRS;
785 	}
786 
787 	for (i = 0; i < cfd->len; i += sizeof(u32)) {
788 		data = be32_to_cpup((__be32 *)&cfd->data[i]);
789 		priv->write(data, &priv->tx_mb->data[i / sizeof(u32)]);
790 	}
791 
792 	can_put_echo_skb(skb, dev, 0, 0);
793 
794 	priv->write(can_id, &priv->tx_mb->can_id);
795 	priv->write(ctrl, &priv->tx_mb->can_ctrl);
796 
797 	/* Errata ERR005829 step8:
798 	 * Write twice INACTIVE(0x8) code to first MB.
799 	 */
800 	priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
801 		    &priv->tx_mb_reserved->can_ctrl);
802 	priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
803 		    &priv->tx_mb_reserved->can_ctrl);
804 
805 	return NETDEV_TX_OK;
806 }
807 
808 static void flexcan_irq_bus_err(struct net_device *dev, u32 reg_esr)
809 {
810 	struct flexcan_priv *priv = netdev_priv(dev);
811 	struct flexcan_regs __iomem *regs = priv->regs;
812 	struct sk_buff *skb;
813 	struct can_frame *cf;
814 	bool rx_errors = false, tx_errors = false;
815 	u32 timestamp;
816 	int err;
817 
818 	timestamp = priv->read(&regs->timer) << 16;
819 
820 	skb = alloc_can_err_skb(dev, &cf);
821 	if (unlikely(!skb))
822 		return;
823 
824 	cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
825 
826 	if (reg_esr & FLEXCAN_ESR_BIT1_ERR) {
827 		netdev_dbg(dev, "BIT1_ERR irq\n");
828 		cf->data[2] |= CAN_ERR_PROT_BIT1;
829 		tx_errors = true;
830 	}
831 	if (reg_esr & FLEXCAN_ESR_BIT0_ERR) {
832 		netdev_dbg(dev, "BIT0_ERR irq\n");
833 		cf->data[2] |= CAN_ERR_PROT_BIT0;
834 		tx_errors = true;
835 	}
836 	if (reg_esr & FLEXCAN_ESR_ACK_ERR) {
837 		netdev_dbg(dev, "ACK_ERR irq\n");
838 		cf->can_id |= CAN_ERR_ACK;
839 		cf->data[3] = CAN_ERR_PROT_LOC_ACK;
840 		tx_errors = true;
841 	}
842 	if (reg_esr & FLEXCAN_ESR_CRC_ERR) {
843 		netdev_dbg(dev, "CRC_ERR irq\n");
844 		cf->data[2] |= CAN_ERR_PROT_BIT;
845 		cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
846 		rx_errors = true;
847 	}
848 	if (reg_esr & FLEXCAN_ESR_FRM_ERR) {
849 		netdev_dbg(dev, "FRM_ERR irq\n");
850 		cf->data[2] |= CAN_ERR_PROT_FORM;
851 		rx_errors = true;
852 	}
853 	if (reg_esr & FLEXCAN_ESR_STF_ERR) {
854 		netdev_dbg(dev, "STF_ERR irq\n");
855 		cf->data[2] |= CAN_ERR_PROT_STUFF;
856 		rx_errors = true;
857 	}
858 
859 	priv->can.can_stats.bus_error++;
860 	if (rx_errors)
861 		dev->stats.rx_errors++;
862 	if (tx_errors)
863 		dev->stats.tx_errors++;
864 
865 	err = can_rx_offload_queue_timestamp(&priv->offload, skb, timestamp);
866 	if (err)
867 		dev->stats.rx_fifo_errors++;
868 }
869 
870 static void flexcan_irq_state(struct net_device *dev, u32 reg_esr)
871 {
872 	struct flexcan_priv *priv = netdev_priv(dev);
873 	struct flexcan_regs __iomem *regs = priv->regs;
874 	struct sk_buff *skb;
875 	struct can_frame *cf;
876 	enum can_state new_state, rx_state, tx_state;
877 	int flt;
878 	struct can_berr_counter bec;
879 	u32 timestamp;
880 	int err;
881 
882 	flt = reg_esr & FLEXCAN_ESR_FLT_CONF_MASK;
883 	if (likely(flt == FLEXCAN_ESR_FLT_CONF_ACTIVE)) {
884 		tx_state = unlikely(reg_esr & FLEXCAN_ESR_TX_WRN) ?
885 			CAN_STATE_ERROR_WARNING : CAN_STATE_ERROR_ACTIVE;
886 		rx_state = unlikely(reg_esr & FLEXCAN_ESR_RX_WRN) ?
887 			CAN_STATE_ERROR_WARNING : CAN_STATE_ERROR_ACTIVE;
888 		new_state = max(tx_state, rx_state);
889 	} else {
890 		__flexcan_get_berr_counter(dev, &bec);
891 		new_state = flt == FLEXCAN_ESR_FLT_CONF_PASSIVE ?
892 			CAN_STATE_ERROR_PASSIVE : CAN_STATE_BUS_OFF;
893 		rx_state = bec.rxerr >= bec.txerr ? new_state : 0;
894 		tx_state = bec.rxerr <= bec.txerr ? new_state : 0;
895 	}
896 
897 	/* state hasn't changed */
898 	if (likely(new_state == priv->can.state))
899 		return;
900 
901 	timestamp = priv->read(&regs->timer) << 16;
902 
903 	skb = alloc_can_err_skb(dev, &cf);
904 	if (unlikely(!skb))
905 		return;
906 
907 	can_change_state(dev, cf, tx_state, rx_state);
908 
909 	if (unlikely(new_state == CAN_STATE_BUS_OFF))
910 		can_bus_off(dev);
911 
912 	err = can_rx_offload_queue_timestamp(&priv->offload, skb, timestamp);
913 	if (err)
914 		dev->stats.rx_fifo_errors++;
915 }
916 
917 static inline u64 flexcan_read64_mask(struct flexcan_priv *priv, void __iomem *addr, u64 mask)
918 {
919 	u64 reg = 0;
920 
921 	if (upper_32_bits(mask))
922 		reg = (u64)priv->read(addr - 4) << 32;
923 	if (lower_32_bits(mask))
924 		reg |= priv->read(addr);
925 
926 	return reg & mask;
927 }
928 
929 static inline void flexcan_write64(struct flexcan_priv *priv, u64 val, void __iomem *addr)
930 {
931 	if (upper_32_bits(val))
932 		priv->write(upper_32_bits(val), addr - 4);
933 	if (lower_32_bits(val))
934 		priv->write(lower_32_bits(val), addr);
935 }
936 
937 static inline u64 flexcan_read_reg_iflag_rx(struct flexcan_priv *priv)
938 {
939 	return flexcan_read64_mask(priv, &priv->regs->iflag1, priv->rx_mask);
940 }
941 
942 static inline u64 flexcan_read_reg_iflag_tx(struct flexcan_priv *priv)
943 {
944 	return flexcan_read64_mask(priv, &priv->regs->iflag1, priv->tx_mask);
945 }
946 
947 static inline struct flexcan_priv *rx_offload_to_priv(struct can_rx_offload *offload)
948 {
949 	return container_of(offload, struct flexcan_priv, offload);
950 }
951 
952 static struct sk_buff *flexcan_mailbox_read(struct can_rx_offload *offload,
953 					    unsigned int n, u32 *timestamp,
954 					    bool drop)
955 {
956 	struct flexcan_priv *priv = rx_offload_to_priv(offload);
957 	struct flexcan_regs __iomem *regs = priv->regs;
958 	struct flexcan_mb __iomem *mb;
959 	struct sk_buff *skb;
960 	struct canfd_frame *cfd;
961 	u32 reg_ctrl, reg_id, reg_iflag1;
962 	int i;
963 
964 	mb = flexcan_get_mb(priv, n);
965 
966 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX) {
967 		u32 code;
968 
969 		do {
970 			reg_ctrl = priv->read(&mb->can_ctrl);
971 		} while (reg_ctrl & FLEXCAN_MB_CODE_RX_BUSY_BIT);
972 
973 		/* is this MB empty? */
974 		code = reg_ctrl & FLEXCAN_MB_CODE_MASK;
975 		if ((code != FLEXCAN_MB_CODE_RX_FULL) &&
976 		    (code != FLEXCAN_MB_CODE_RX_OVERRUN))
977 			return NULL;
978 
979 		if (code == FLEXCAN_MB_CODE_RX_OVERRUN) {
980 			/* This MB was overrun, we lost data */
981 			offload->dev->stats.rx_over_errors++;
982 			offload->dev->stats.rx_errors++;
983 		}
984 	} else {
985 		reg_iflag1 = priv->read(&regs->iflag1);
986 		if (!(reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE))
987 			return NULL;
988 
989 		reg_ctrl = priv->read(&mb->can_ctrl);
990 	}
991 
992 	if (unlikely(drop)) {
993 		skb = ERR_PTR(-ENOBUFS);
994 		goto mark_as_read;
995 	}
996 
997 	if (reg_ctrl & FLEXCAN_MB_CNT_EDL)
998 		skb = alloc_canfd_skb(offload->dev, &cfd);
999 	else
1000 		skb = alloc_can_skb(offload->dev, (struct can_frame **)&cfd);
1001 	if (unlikely(!skb)) {
1002 		skb = ERR_PTR(-ENOMEM);
1003 		goto mark_as_read;
1004 	}
1005 
1006 	/* increase timstamp to full 32 bit */
1007 	*timestamp = reg_ctrl << 16;
1008 
1009 	reg_id = priv->read(&mb->can_id);
1010 	if (reg_ctrl & FLEXCAN_MB_CNT_IDE)
1011 		cfd->can_id = ((reg_id >> 0) & CAN_EFF_MASK) | CAN_EFF_FLAG;
1012 	else
1013 		cfd->can_id = (reg_id >> 18) & CAN_SFF_MASK;
1014 
1015 	if (reg_ctrl & FLEXCAN_MB_CNT_EDL) {
1016 		cfd->len = can_fd_dlc2len((reg_ctrl >> 16) & 0xf);
1017 
1018 		if (reg_ctrl & FLEXCAN_MB_CNT_BRS)
1019 			cfd->flags |= CANFD_BRS;
1020 	} else {
1021 		cfd->len = can_cc_dlc2len((reg_ctrl >> 16) & 0xf);
1022 
1023 		if (reg_ctrl & FLEXCAN_MB_CNT_RTR)
1024 			cfd->can_id |= CAN_RTR_FLAG;
1025 	}
1026 
1027 	if (reg_ctrl & FLEXCAN_MB_CNT_ESI)
1028 		cfd->flags |= CANFD_ESI;
1029 
1030 	for (i = 0; i < cfd->len; i += sizeof(u32)) {
1031 		__be32 data = cpu_to_be32(priv->read(&mb->data[i / sizeof(u32)]));
1032 		*(__be32 *)(cfd->data + i) = data;
1033 	}
1034 
1035  mark_as_read:
1036 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX)
1037 		flexcan_write64(priv, FLEXCAN_IFLAG_MB(n), &regs->iflag1);
1038 	else
1039 		priv->write(FLEXCAN_IFLAG_RX_FIFO_AVAILABLE, &regs->iflag1);
1040 
1041 	/* Read the Free Running Timer. It is optional but recommended
1042 	 * to unlock Mailbox as soon as possible and make it available
1043 	 * for reception.
1044 	 */
1045 	priv->read(&regs->timer);
1046 
1047 	return skb;
1048 }
1049 
1050 static irqreturn_t flexcan_irq(int irq, void *dev_id)
1051 {
1052 	struct net_device *dev = dev_id;
1053 	struct net_device_stats *stats = &dev->stats;
1054 	struct flexcan_priv *priv = netdev_priv(dev);
1055 	struct flexcan_regs __iomem *regs = priv->regs;
1056 	irqreturn_t handled = IRQ_NONE;
1057 	u64 reg_iflag_tx;
1058 	u32 reg_esr;
1059 	enum can_state last_state = priv->can.state;
1060 
1061 	/* reception interrupt */
1062 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX) {
1063 		u64 reg_iflag_rx;
1064 		int ret;
1065 
1066 		while ((reg_iflag_rx = flexcan_read_reg_iflag_rx(priv))) {
1067 			handled = IRQ_HANDLED;
1068 			ret = can_rx_offload_irq_offload_timestamp(&priv->offload,
1069 								   reg_iflag_rx);
1070 			if (!ret)
1071 				break;
1072 		}
1073 	} else {
1074 		u32 reg_iflag1;
1075 
1076 		reg_iflag1 = priv->read(&regs->iflag1);
1077 		if (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE) {
1078 			handled = IRQ_HANDLED;
1079 			can_rx_offload_irq_offload_fifo(&priv->offload);
1080 		}
1081 
1082 		/* FIFO overflow interrupt */
1083 		if (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_OVERFLOW) {
1084 			handled = IRQ_HANDLED;
1085 			priv->write(FLEXCAN_IFLAG_RX_FIFO_OVERFLOW,
1086 				    &regs->iflag1);
1087 			dev->stats.rx_over_errors++;
1088 			dev->stats.rx_errors++;
1089 		}
1090 	}
1091 
1092 	reg_iflag_tx = flexcan_read_reg_iflag_tx(priv);
1093 
1094 	/* transmission complete interrupt */
1095 	if (reg_iflag_tx & priv->tx_mask) {
1096 		u32 reg_ctrl = priv->read(&priv->tx_mb->can_ctrl);
1097 
1098 		handled = IRQ_HANDLED;
1099 		stats->tx_bytes +=
1100 			can_rx_offload_get_echo_skb(&priv->offload, 0,
1101 						    reg_ctrl << 16, NULL);
1102 		stats->tx_packets++;
1103 
1104 		/* after sending a RTR frame MB is in RX mode */
1105 		priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
1106 			    &priv->tx_mb->can_ctrl);
1107 		flexcan_write64(priv, priv->tx_mask, &regs->iflag1);
1108 		netif_wake_queue(dev);
1109 	}
1110 
1111 	reg_esr = priv->read(&regs->esr);
1112 
1113 	/* ACK all bus error, state change and wake IRQ sources */
1114 	if (reg_esr & (FLEXCAN_ESR_ALL_INT | FLEXCAN_ESR_WAK_INT)) {
1115 		handled = IRQ_HANDLED;
1116 		priv->write(reg_esr & (FLEXCAN_ESR_ALL_INT | FLEXCAN_ESR_WAK_INT), &regs->esr);
1117 	}
1118 
1119 	/* state change interrupt or broken error state quirk fix is enabled */
1120 	if ((reg_esr & FLEXCAN_ESR_ERR_STATE) ||
1121 	    (priv->devtype_data.quirks & (FLEXCAN_QUIRK_BROKEN_WERR_STATE |
1122 					   FLEXCAN_QUIRK_BROKEN_PERR_STATE)))
1123 		flexcan_irq_state(dev, reg_esr);
1124 
1125 	/* bus error IRQ - handle if bus error reporting is activated */
1126 	if ((reg_esr & FLEXCAN_ESR_ERR_BUS) &&
1127 	    (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
1128 		flexcan_irq_bus_err(dev, reg_esr);
1129 
1130 	/* availability of error interrupt among state transitions in case
1131 	 * bus error reporting is de-activated and
1132 	 * FLEXCAN_QUIRK_BROKEN_PERR_STATE is enabled:
1133 	 *  +--------------------------------------------------------------+
1134 	 *  | +----------------------------------------------+ [stopped /  |
1135 	 *  | |                                              |  sleeping] -+
1136 	 *  +-+-> active <-> warning <-> passive -> bus off -+
1137 	 *        ___________^^^^^^^^^^^^_______________________________
1138 	 *        disabled(1)  enabled             disabled
1139 	 *
1140 	 * (1): enabled if FLEXCAN_QUIRK_BROKEN_WERR_STATE is enabled
1141 	 */
1142 	if ((last_state != priv->can.state) &&
1143 	    (priv->devtype_data.quirks & FLEXCAN_QUIRK_BROKEN_PERR_STATE) &&
1144 	    !(priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)) {
1145 		switch (priv->can.state) {
1146 		case CAN_STATE_ERROR_ACTIVE:
1147 			if (priv->devtype_data.quirks &
1148 			    FLEXCAN_QUIRK_BROKEN_WERR_STATE)
1149 				flexcan_error_irq_enable(priv);
1150 			else
1151 				flexcan_error_irq_disable(priv);
1152 			break;
1153 
1154 		case CAN_STATE_ERROR_WARNING:
1155 			flexcan_error_irq_enable(priv);
1156 			break;
1157 
1158 		case CAN_STATE_ERROR_PASSIVE:
1159 		case CAN_STATE_BUS_OFF:
1160 			flexcan_error_irq_disable(priv);
1161 			break;
1162 
1163 		default:
1164 			break;
1165 		}
1166 	}
1167 
1168 	if (handled)
1169 		can_rx_offload_irq_finish(&priv->offload);
1170 
1171 	return handled;
1172 }
1173 
1174 static void flexcan_set_bittiming_ctrl(const struct net_device *dev)
1175 {
1176 	const struct flexcan_priv *priv = netdev_priv(dev);
1177 	const struct can_bittiming *bt = &priv->can.bittiming;
1178 	struct flexcan_regs __iomem *regs = priv->regs;
1179 	u32 reg;
1180 
1181 	reg = priv->read(&regs->ctrl);
1182 	reg &= ~(FLEXCAN_CTRL_PRESDIV(0xff) |
1183 		 FLEXCAN_CTRL_RJW(0x3) |
1184 		 FLEXCAN_CTRL_PSEG1(0x7) |
1185 		 FLEXCAN_CTRL_PSEG2(0x7) |
1186 		 FLEXCAN_CTRL_PROPSEG(0x7));
1187 
1188 	reg |= FLEXCAN_CTRL_PRESDIV(bt->brp - 1) |
1189 		FLEXCAN_CTRL_PSEG1(bt->phase_seg1 - 1) |
1190 		FLEXCAN_CTRL_PSEG2(bt->phase_seg2 - 1) |
1191 		FLEXCAN_CTRL_RJW(bt->sjw - 1) |
1192 		FLEXCAN_CTRL_PROPSEG(bt->prop_seg - 1);
1193 
1194 	netdev_dbg(dev, "writing ctrl=0x%08x\n", reg);
1195 	priv->write(reg, &regs->ctrl);
1196 
1197 	/* print chip status */
1198 	netdev_dbg(dev, "%s: mcr=0x%08x ctrl=0x%08x\n", __func__,
1199 		   priv->read(&regs->mcr), priv->read(&regs->ctrl));
1200 }
1201 
1202 static void flexcan_set_bittiming_cbt(const struct net_device *dev)
1203 {
1204 	struct flexcan_priv *priv = netdev_priv(dev);
1205 	struct can_bittiming *bt = &priv->can.bittiming;
1206 	struct can_bittiming *dbt = &priv->can.data_bittiming;
1207 	struct flexcan_regs __iomem *regs = priv->regs;
1208 	u32 reg_cbt, reg_fdctrl;
1209 
1210 	/* CBT */
1211 	/* CBT[EPSEG1] is 5 bit long and CBT[EPROPSEG] is 6 bit
1212 	 * long. The can_calc_bittiming() tries to divide the tseg1
1213 	 * equally between phase_seg1 and prop_seg, which may not fit
1214 	 * in CBT register. Therefore, if phase_seg1 is more than
1215 	 * possible value, increase prop_seg and decrease phase_seg1.
1216 	 */
1217 	if (bt->phase_seg1 > 0x20) {
1218 		bt->prop_seg += (bt->phase_seg1 - 0x20);
1219 		bt->phase_seg1 = 0x20;
1220 	}
1221 
1222 	reg_cbt = FLEXCAN_CBT_BTF |
1223 		FIELD_PREP(FLEXCAN_CBT_EPRESDIV_MASK, bt->brp - 1) |
1224 		FIELD_PREP(FLEXCAN_CBT_ERJW_MASK, bt->sjw - 1) |
1225 		FIELD_PREP(FLEXCAN_CBT_EPROPSEG_MASK, bt->prop_seg - 1) |
1226 		FIELD_PREP(FLEXCAN_CBT_EPSEG1_MASK, bt->phase_seg1 - 1) |
1227 		FIELD_PREP(FLEXCAN_CBT_EPSEG2_MASK, bt->phase_seg2 - 1);
1228 
1229 	netdev_dbg(dev, "writing cbt=0x%08x\n", reg_cbt);
1230 	priv->write(reg_cbt, &regs->cbt);
1231 
1232 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
1233 		u32 reg_fdcbt, reg_ctrl2;
1234 
1235 		if (bt->brp != dbt->brp)
1236 			netdev_warn(dev, "Data brp=%d and brp=%d don't match, this may result in a phase error. Consider using different bitrate and/or data bitrate.\n",
1237 				    dbt->brp, bt->brp);
1238 
1239 		/* FDCBT */
1240 		/* FDCBT[FPSEG1] is 3 bit long and FDCBT[FPROPSEG] is
1241 		 * 5 bit long. The can_calc_bittiming tries to divide
1242 		 * the tseg1 equally between phase_seg1 and prop_seg,
1243 		 * which may not fit in FDCBT register. Therefore, if
1244 		 * phase_seg1 is more than possible value, increase
1245 		 * prop_seg and decrease phase_seg1
1246 		 */
1247 		if (dbt->phase_seg1 > 0x8) {
1248 			dbt->prop_seg += (dbt->phase_seg1 - 0x8);
1249 			dbt->phase_seg1 = 0x8;
1250 		}
1251 
1252 		reg_fdcbt = priv->read(&regs->fdcbt);
1253 		reg_fdcbt &= ~(FIELD_PREP(FLEXCAN_FDCBT_FPRESDIV_MASK, 0x3ff) |
1254 			       FIELD_PREP(FLEXCAN_FDCBT_FRJW_MASK, 0x7) |
1255 			       FIELD_PREP(FLEXCAN_FDCBT_FPROPSEG_MASK, 0x1f) |
1256 			       FIELD_PREP(FLEXCAN_FDCBT_FPSEG1_MASK, 0x7) |
1257 			       FIELD_PREP(FLEXCAN_FDCBT_FPSEG2_MASK, 0x7));
1258 
1259 		reg_fdcbt |= FIELD_PREP(FLEXCAN_FDCBT_FPRESDIV_MASK, dbt->brp - 1) |
1260 			FIELD_PREP(FLEXCAN_FDCBT_FRJW_MASK, dbt->sjw - 1) |
1261 			FIELD_PREP(FLEXCAN_FDCBT_FPROPSEG_MASK, dbt->prop_seg) |
1262 			FIELD_PREP(FLEXCAN_FDCBT_FPSEG1_MASK, dbt->phase_seg1 - 1) |
1263 			FIELD_PREP(FLEXCAN_FDCBT_FPSEG2_MASK, dbt->phase_seg2 - 1);
1264 
1265 		netdev_dbg(dev, "writing fdcbt=0x%08x\n", reg_fdcbt);
1266 		priv->write(reg_fdcbt, &regs->fdcbt);
1267 
1268 		/* CTRL2 */
1269 		reg_ctrl2 = priv->read(&regs->ctrl2);
1270 		reg_ctrl2 &= ~FLEXCAN_CTRL2_ISOCANFDEN;
1271 		if (!(priv->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO))
1272 			reg_ctrl2 |= FLEXCAN_CTRL2_ISOCANFDEN;
1273 
1274 		netdev_dbg(dev, "writing ctrl2=0x%08x\n", reg_ctrl2);
1275 		priv->write(reg_ctrl2, &regs->ctrl2);
1276 	}
1277 
1278 	/* FDCTRL */
1279 	reg_fdctrl = priv->read(&regs->fdctrl);
1280 	reg_fdctrl &= ~(FLEXCAN_FDCTRL_FDRATE |
1281 			FIELD_PREP(FLEXCAN_FDCTRL_TDCOFF, 0x1f));
1282 
1283 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
1284 		reg_fdctrl |= FLEXCAN_FDCTRL_FDRATE;
1285 
1286 		if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) {
1287 			/* TDC must be disabled for Loop Back mode */
1288 			reg_fdctrl &= ~FLEXCAN_FDCTRL_TDCEN;
1289 		} else {
1290 			reg_fdctrl |= FLEXCAN_FDCTRL_TDCEN |
1291 				FIELD_PREP(FLEXCAN_FDCTRL_TDCOFF,
1292 					   ((dbt->phase_seg1 - 1) +
1293 					    dbt->prop_seg + 2) *
1294 					   ((dbt->brp - 1 ) + 1));
1295 		}
1296 	}
1297 
1298 	netdev_dbg(dev, "writing fdctrl=0x%08x\n", reg_fdctrl);
1299 	priv->write(reg_fdctrl, &regs->fdctrl);
1300 
1301 	netdev_dbg(dev, "%s: mcr=0x%08x ctrl=0x%08x ctrl2=0x%08x fdctrl=0x%08x cbt=0x%08x fdcbt=0x%08x\n",
1302 		   __func__,
1303 		   priv->read(&regs->mcr), priv->read(&regs->ctrl),
1304 		   priv->read(&regs->ctrl2), priv->read(&regs->fdctrl),
1305 		   priv->read(&regs->cbt), priv->read(&regs->fdcbt));
1306 }
1307 
1308 static void flexcan_set_bittiming(struct net_device *dev)
1309 {
1310 	const struct flexcan_priv *priv = netdev_priv(dev);
1311 	struct flexcan_regs __iomem *regs = priv->regs;
1312 	u32 reg;
1313 
1314 	reg = priv->read(&regs->ctrl);
1315 	reg &= ~(FLEXCAN_CTRL_LPB | FLEXCAN_CTRL_SMP |
1316 		 FLEXCAN_CTRL_LOM);
1317 
1318 	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
1319 		reg |= FLEXCAN_CTRL_LPB;
1320 	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
1321 		reg |= FLEXCAN_CTRL_LOM;
1322 	if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
1323 		reg |= FLEXCAN_CTRL_SMP;
1324 
1325 	netdev_dbg(dev, "writing ctrl=0x%08x\n", reg);
1326 	priv->write(reg, &regs->ctrl);
1327 
1328 	if (priv->can.ctrlmode_supported & CAN_CTRLMODE_FD)
1329 		return flexcan_set_bittiming_cbt(dev);
1330 	else
1331 		return flexcan_set_bittiming_ctrl(dev);
1332 }
1333 
1334 static void flexcan_ram_init(struct net_device *dev)
1335 {
1336 	struct flexcan_priv *priv = netdev_priv(dev);
1337 	struct flexcan_regs __iomem *regs = priv->regs;
1338 	u32 reg_ctrl2;
1339 
1340 	/* 11.8.3.13 Detection and correction of memory errors:
1341 	 * CTRL2[WRMFRZ] grants write access to all memory positions
1342 	 * that require initialization, ranging from 0x080 to 0xADF
1343 	 * and from 0xF28 to 0xFFF when the CAN FD feature is enabled.
1344 	 * The RXMGMASK, RX14MASK, RX15MASK, and RXFGMASK registers
1345 	 * need to be initialized as well. MCR[RFEN] must not be set
1346 	 * during memory initialization.
1347 	 */
1348 	reg_ctrl2 = priv->read(&regs->ctrl2);
1349 	reg_ctrl2 |= FLEXCAN_CTRL2_WRMFRZ;
1350 	priv->write(reg_ctrl2, &regs->ctrl2);
1351 
1352 	memset_io(&regs->init, 0, sizeof(regs->init));
1353 
1354 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
1355 		memset_io(&regs->init_fd, 0, sizeof(regs->init_fd));
1356 
1357 	reg_ctrl2 &= ~FLEXCAN_CTRL2_WRMFRZ;
1358 	priv->write(reg_ctrl2, &regs->ctrl2);
1359 }
1360 
1361 static int flexcan_rx_offload_setup(struct net_device *dev)
1362 {
1363 	struct flexcan_priv *priv = netdev_priv(dev);
1364 	int err;
1365 
1366 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
1367 		priv->mb_size = sizeof(struct flexcan_mb) + CANFD_MAX_DLEN;
1368 	else
1369 		priv->mb_size = sizeof(struct flexcan_mb) + CAN_MAX_DLEN;
1370 
1371 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_NR_MB_16)
1372 		priv->mb_count = 16;
1373 	else
1374 		priv->mb_count = (sizeof(priv->regs->mb[0]) / priv->mb_size) +
1375 				 (sizeof(priv->regs->mb[1]) / priv->mb_size);
1376 
1377 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX)
1378 		priv->tx_mb_reserved =
1379 			flexcan_get_mb(priv, FLEXCAN_TX_MB_RESERVED_RX_MAILBOX);
1380 	else
1381 		priv->tx_mb_reserved =
1382 			flexcan_get_mb(priv, FLEXCAN_TX_MB_RESERVED_RX_FIFO);
1383 	priv->tx_mb_idx = priv->mb_count - 1;
1384 	priv->tx_mb = flexcan_get_mb(priv, priv->tx_mb_idx);
1385 	priv->tx_mask = FLEXCAN_IFLAG_MB(priv->tx_mb_idx);
1386 
1387 	priv->offload.mailbox_read = flexcan_mailbox_read;
1388 
1389 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX) {
1390 		priv->offload.mb_first = FLEXCAN_RX_MB_RX_MAILBOX_FIRST;
1391 		priv->offload.mb_last = priv->mb_count - 2;
1392 
1393 		priv->rx_mask = GENMASK_ULL(priv->offload.mb_last,
1394 					    priv->offload.mb_first);
1395 		err = can_rx_offload_add_timestamp(dev, &priv->offload);
1396 	} else {
1397 		priv->rx_mask = FLEXCAN_IFLAG_RX_FIFO_OVERFLOW |
1398 			FLEXCAN_IFLAG_RX_FIFO_AVAILABLE;
1399 		err = can_rx_offload_add_fifo(dev, &priv->offload,
1400 					      FLEXCAN_NAPI_WEIGHT);
1401 	}
1402 
1403 	return err;
1404 }
1405 
1406 static void flexcan_chip_interrupts_enable(const struct net_device *dev)
1407 {
1408 	const struct flexcan_priv *priv = netdev_priv(dev);
1409 	struct flexcan_regs __iomem *regs = priv->regs;
1410 	u64 reg_imask;
1411 
1412 	disable_irq(dev->irq);
1413 	priv->write(priv->reg_ctrl_default, &regs->ctrl);
1414 	reg_imask = priv->rx_mask | priv->tx_mask;
1415 	priv->write(upper_32_bits(reg_imask), &regs->imask2);
1416 	priv->write(lower_32_bits(reg_imask), &regs->imask1);
1417 	enable_irq(dev->irq);
1418 }
1419 
1420 static void flexcan_chip_interrupts_disable(const struct net_device *dev)
1421 {
1422 	const struct flexcan_priv *priv = netdev_priv(dev);
1423 	struct flexcan_regs __iomem *regs = priv->regs;
1424 
1425 	priv->write(0, &regs->imask2);
1426 	priv->write(0, &regs->imask1);
1427 	priv->write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL,
1428 		    &regs->ctrl);
1429 }
1430 
1431 /* flexcan_chip_start
1432  *
1433  * this functions is entered with clocks enabled
1434  *
1435  */
1436 static int flexcan_chip_start(struct net_device *dev)
1437 {
1438 	struct flexcan_priv *priv = netdev_priv(dev);
1439 	struct flexcan_regs __iomem *regs = priv->regs;
1440 	u32 reg_mcr, reg_ctrl, reg_ctrl2, reg_mecr;
1441 	int err, i;
1442 	struct flexcan_mb __iomem *mb;
1443 
1444 	/* enable module */
1445 	err = flexcan_chip_enable(priv);
1446 	if (err)
1447 		return err;
1448 
1449 	/* soft reset */
1450 	err = flexcan_chip_softreset(priv);
1451 	if (err)
1452 		goto out_chip_disable;
1453 
1454 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SUPPORT_ECC)
1455 		flexcan_ram_init(dev);
1456 
1457 	flexcan_set_bittiming(dev);
1458 
1459 	/* set freeze, halt */
1460 	err = flexcan_chip_freeze(priv);
1461 	if (err)
1462 		goto out_chip_disable;
1463 
1464 	/* MCR
1465 	 *
1466 	 * only supervisor access
1467 	 * enable warning int
1468 	 * enable individual RX masking
1469 	 * choose format C
1470 	 * set max mailbox number
1471 	 */
1472 	reg_mcr = priv->read(&regs->mcr);
1473 	reg_mcr &= ~FLEXCAN_MCR_MAXMB(0xff);
1474 	reg_mcr |= FLEXCAN_MCR_SUPV | FLEXCAN_MCR_WRN_EN | FLEXCAN_MCR_IRMQ |
1475 		FLEXCAN_MCR_IDAM_C | FLEXCAN_MCR_MAXMB(priv->tx_mb_idx);
1476 
1477 	/* MCR
1478 	 *
1479 	 * FIFO:
1480 	 * - disable for mailbox mode
1481 	 * - enable for FIFO mode
1482 	 */
1483 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX)
1484 		reg_mcr &= ~FLEXCAN_MCR_FEN;
1485 	else
1486 		reg_mcr |= FLEXCAN_MCR_FEN;
1487 
1488 	/* MCR
1489 	 *
1490 	 * NOTE: In loopback mode, the CAN_MCR[SRXDIS] cannot be
1491 	 *       asserted because this will impede the self reception
1492 	 *       of a transmitted message. This is not documented in
1493 	 *       earlier versions of flexcan block guide.
1494 	 *
1495 	 * Self Reception:
1496 	 * - enable Self Reception for loopback mode
1497 	 *   (by clearing "Self Reception Disable" bit)
1498 	 * - disable for normal operation
1499 	 */
1500 	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
1501 		reg_mcr &= ~FLEXCAN_MCR_SRX_DIS;
1502 	else
1503 		reg_mcr |= FLEXCAN_MCR_SRX_DIS;
1504 
1505 	/* MCR - CAN-FD */
1506 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
1507 		reg_mcr |= FLEXCAN_MCR_FDEN;
1508 	else
1509 		reg_mcr &= ~FLEXCAN_MCR_FDEN;
1510 
1511 	netdev_dbg(dev, "%s: writing mcr=0x%08x", __func__, reg_mcr);
1512 	priv->write(reg_mcr, &regs->mcr);
1513 
1514 	/* CTRL
1515 	 *
1516 	 * disable timer sync feature
1517 	 *
1518 	 * disable auto busoff recovery
1519 	 * transmit lowest buffer first
1520 	 *
1521 	 * enable tx and rx warning interrupt
1522 	 * enable bus off interrupt
1523 	 * (== FLEXCAN_CTRL_ERR_STATE)
1524 	 */
1525 	reg_ctrl = priv->read(&regs->ctrl);
1526 	reg_ctrl &= ~FLEXCAN_CTRL_TSYN;
1527 	reg_ctrl |= FLEXCAN_CTRL_BOFF_REC | FLEXCAN_CTRL_LBUF |
1528 		FLEXCAN_CTRL_ERR_STATE;
1529 
1530 	/* enable the "error interrupt" (FLEXCAN_CTRL_ERR_MSK),
1531 	 * on most Flexcan cores, too. Otherwise we don't get
1532 	 * any error warning or passive interrupts.
1533 	 */
1534 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_BROKEN_WERR_STATE ||
1535 	    priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
1536 		reg_ctrl |= FLEXCAN_CTRL_ERR_MSK;
1537 	else
1538 		reg_ctrl &= ~FLEXCAN_CTRL_ERR_MSK;
1539 
1540 	/* save for later use */
1541 	priv->reg_ctrl_default = reg_ctrl;
1542 	/* leave interrupts disabled for now */
1543 	reg_ctrl &= ~FLEXCAN_CTRL_ERR_ALL;
1544 	netdev_dbg(dev, "%s: writing ctrl=0x%08x", __func__, reg_ctrl);
1545 	priv->write(reg_ctrl, &regs->ctrl);
1546 
1547 	if ((priv->devtype_data.quirks & FLEXCAN_QUIRK_ENABLE_EACEN_RRS)) {
1548 		reg_ctrl2 = priv->read(&regs->ctrl2);
1549 		reg_ctrl2 |= FLEXCAN_CTRL2_EACEN | FLEXCAN_CTRL2_RRS;
1550 		priv->write(reg_ctrl2, &regs->ctrl2);
1551 	}
1552 
1553 	if (priv->can.ctrlmode_supported & CAN_CTRLMODE_FD) {
1554 		u32 reg_fdctrl;
1555 
1556 		reg_fdctrl = priv->read(&regs->fdctrl);
1557 		reg_fdctrl &= ~(FIELD_PREP(FLEXCAN_FDCTRL_MBDSR1, 0x3) |
1558 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR0, 0x3));
1559 
1560 		if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
1561 			reg_fdctrl |=
1562 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR1,
1563 					   FLEXCAN_FDCTRL_MBDSR_64) |
1564 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR0,
1565 					   FLEXCAN_FDCTRL_MBDSR_64);
1566 		} else {
1567 			reg_fdctrl |=
1568 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR1,
1569 					   FLEXCAN_FDCTRL_MBDSR_8) |
1570 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR0,
1571 					   FLEXCAN_FDCTRL_MBDSR_8);
1572 		}
1573 
1574 		netdev_dbg(dev, "%s: writing fdctrl=0x%08x",
1575 			   __func__, reg_fdctrl);
1576 		priv->write(reg_fdctrl, &regs->fdctrl);
1577 	}
1578 
1579 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX) {
1580 		for (i = priv->offload.mb_first; i <= priv->offload.mb_last; i++) {
1581 			mb = flexcan_get_mb(priv, i);
1582 			priv->write(FLEXCAN_MB_CODE_RX_EMPTY,
1583 				    &mb->can_ctrl);
1584 		}
1585 	} else {
1586 		/* clear and invalidate unused mailboxes first */
1587 		for (i = FLEXCAN_TX_MB_RESERVED_RX_FIFO; i < priv->mb_count; i++) {
1588 			mb = flexcan_get_mb(priv, i);
1589 			priv->write(FLEXCAN_MB_CODE_RX_INACTIVE,
1590 				    &mb->can_ctrl);
1591 		}
1592 	}
1593 
1594 	/* Errata ERR005829: mark first TX mailbox as INACTIVE */
1595 	priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
1596 		    &priv->tx_mb_reserved->can_ctrl);
1597 
1598 	/* mark TX mailbox as INACTIVE */
1599 	priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
1600 		    &priv->tx_mb->can_ctrl);
1601 
1602 	/* acceptance mask/acceptance code (accept everything) */
1603 	priv->write(0x0, &regs->rxgmask);
1604 	priv->write(0x0, &regs->rx14mask);
1605 	priv->write(0x0, &regs->rx15mask);
1606 
1607 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_DISABLE_RXFG)
1608 		priv->write(0x0, &regs->rxfgmask);
1609 
1610 	/* clear acceptance filters */
1611 	for (i = 0; i < priv->mb_count; i++)
1612 		priv->write(0, &regs->rximr[i]);
1613 
1614 	/* On Vybrid, disable non-correctable errors interrupt and
1615 	 * freeze mode. It still can correct the correctable errors
1616 	 * when HW supports ECC.
1617 	 *
1618 	 * This also works around errata e5295 which generates false
1619 	 * positive memory errors and put the device in freeze mode.
1620 	 */
1621 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_DISABLE_MECR) {
1622 		/* Follow the protocol as described in "Detection
1623 		 * and Correction of Memory Errors" to write to
1624 		 * MECR register (step 1 - 5)
1625 		 *
1626 		 * 1. By default, CTRL2[ECRWRE] = 0, MECR[ECRWRDIS] = 1
1627 		 * 2. set CTRL2[ECRWRE]
1628 		 */
1629 		reg_ctrl2 = priv->read(&regs->ctrl2);
1630 		reg_ctrl2 |= FLEXCAN_CTRL2_ECRWRE;
1631 		priv->write(reg_ctrl2, &regs->ctrl2);
1632 
1633 		/* 3. clear MECR[ECRWRDIS] */
1634 		reg_mecr = priv->read(&regs->mecr);
1635 		reg_mecr &= ~FLEXCAN_MECR_ECRWRDIS;
1636 		priv->write(reg_mecr, &regs->mecr);
1637 
1638 		/* 4. all writes to MECR must keep MECR[ECRWRDIS] cleared */
1639 		reg_mecr &= ~(FLEXCAN_MECR_NCEFAFRZ | FLEXCAN_MECR_HANCEI_MSK |
1640 			      FLEXCAN_MECR_FANCEI_MSK);
1641 		priv->write(reg_mecr, &regs->mecr);
1642 
1643 		/* 5. after configuration done, lock MECR by either
1644 		 * setting MECR[ECRWRDIS] or clearing CTRL2[ECRWRE]
1645 		 */
1646 		reg_mecr |= FLEXCAN_MECR_ECRWRDIS;
1647 		priv->write(reg_mecr, &regs->mecr);
1648 
1649 		reg_ctrl2 &= ~FLEXCAN_CTRL2_ECRWRE;
1650 		priv->write(reg_ctrl2, &regs->ctrl2);
1651 	}
1652 
1653 	/* synchronize with the can bus */
1654 	err = flexcan_chip_unfreeze(priv);
1655 	if (err)
1656 		goto out_chip_disable;
1657 
1658 	priv->can.state = CAN_STATE_ERROR_ACTIVE;
1659 
1660 	/* print chip status */
1661 	netdev_dbg(dev, "%s: reading mcr=0x%08x ctrl=0x%08x\n", __func__,
1662 		   priv->read(&regs->mcr), priv->read(&regs->ctrl));
1663 
1664 	return 0;
1665 
1666  out_chip_disable:
1667 	flexcan_chip_disable(priv);
1668 	return err;
1669 }
1670 
1671 /* __flexcan_chip_stop
1672  *
1673  * this function is entered with clocks enabled
1674  */
1675 static int __flexcan_chip_stop(struct net_device *dev, bool disable_on_error)
1676 {
1677 	struct flexcan_priv *priv = netdev_priv(dev);
1678 	int err;
1679 
1680 	/* freeze + disable module */
1681 	err = flexcan_chip_freeze(priv);
1682 	if (err && !disable_on_error)
1683 		return err;
1684 	err = flexcan_chip_disable(priv);
1685 	if (err && !disable_on_error)
1686 		goto out_chip_unfreeze;
1687 
1688 	priv->can.state = CAN_STATE_STOPPED;
1689 
1690 	return 0;
1691 
1692  out_chip_unfreeze:
1693 	flexcan_chip_unfreeze(priv);
1694 
1695 	return err;
1696 }
1697 
1698 static inline int flexcan_chip_stop_disable_on_error(struct net_device *dev)
1699 {
1700 	return __flexcan_chip_stop(dev, true);
1701 }
1702 
1703 static inline int flexcan_chip_stop(struct net_device *dev)
1704 {
1705 	return __flexcan_chip_stop(dev, false);
1706 }
1707 
1708 static int flexcan_open(struct net_device *dev)
1709 {
1710 	struct flexcan_priv *priv = netdev_priv(dev);
1711 	int err;
1712 
1713 	if ((priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) &&
1714 	    (priv->can.ctrlmode & CAN_CTRLMODE_FD)) {
1715 		netdev_err(dev, "Three Samples mode and CAN-FD mode can't be used together\n");
1716 		return -EINVAL;
1717 	}
1718 
1719 	err = pm_runtime_resume_and_get(priv->dev);
1720 	if (err < 0)
1721 		return err;
1722 
1723 	err = open_candev(dev);
1724 	if (err)
1725 		goto out_runtime_put;
1726 
1727 	err = flexcan_transceiver_enable(priv);
1728 	if (err)
1729 		goto out_close;
1730 
1731 	err = flexcan_rx_offload_setup(dev);
1732 	if (err)
1733 		goto out_transceiver_disable;
1734 
1735 	err = flexcan_chip_start(dev);
1736 	if (err)
1737 		goto out_can_rx_offload_del;
1738 
1739 	can_rx_offload_enable(&priv->offload);
1740 
1741 	err = request_irq(dev->irq, flexcan_irq, IRQF_SHARED, dev->name, dev);
1742 	if (err)
1743 		goto out_can_rx_offload_disable;
1744 
1745 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_NR_IRQ_3) {
1746 		err = request_irq(priv->irq_boff,
1747 				  flexcan_irq, IRQF_SHARED, dev->name, dev);
1748 		if (err)
1749 			goto out_free_irq;
1750 
1751 		err = request_irq(priv->irq_err,
1752 				  flexcan_irq, IRQF_SHARED, dev->name, dev);
1753 		if (err)
1754 			goto out_free_irq_boff;
1755 	}
1756 
1757 	flexcan_chip_interrupts_enable(dev);
1758 
1759 	netif_start_queue(dev);
1760 
1761 	return 0;
1762 
1763  out_free_irq_boff:
1764 	free_irq(priv->irq_boff, dev);
1765  out_free_irq:
1766 	free_irq(dev->irq, dev);
1767  out_can_rx_offload_disable:
1768 	can_rx_offload_disable(&priv->offload);
1769 	flexcan_chip_stop(dev);
1770  out_can_rx_offload_del:
1771 	can_rx_offload_del(&priv->offload);
1772  out_transceiver_disable:
1773 	flexcan_transceiver_disable(priv);
1774  out_close:
1775 	close_candev(dev);
1776  out_runtime_put:
1777 	pm_runtime_put(priv->dev);
1778 
1779 	return err;
1780 }
1781 
1782 static int flexcan_close(struct net_device *dev)
1783 {
1784 	struct flexcan_priv *priv = netdev_priv(dev);
1785 
1786 	netif_stop_queue(dev);
1787 	flexcan_chip_interrupts_disable(dev);
1788 
1789 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_NR_IRQ_3) {
1790 		free_irq(priv->irq_err, dev);
1791 		free_irq(priv->irq_boff, dev);
1792 	}
1793 
1794 	free_irq(dev->irq, dev);
1795 	can_rx_offload_disable(&priv->offload);
1796 	flexcan_chip_stop_disable_on_error(dev);
1797 
1798 	can_rx_offload_del(&priv->offload);
1799 	flexcan_transceiver_disable(priv);
1800 	close_candev(dev);
1801 
1802 	pm_runtime_put(priv->dev);
1803 
1804 	return 0;
1805 }
1806 
1807 static int flexcan_set_mode(struct net_device *dev, enum can_mode mode)
1808 {
1809 	int err;
1810 
1811 	switch (mode) {
1812 	case CAN_MODE_START:
1813 		err = flexcan_chip_start(dev);
1814 		if (err)
1815 			return err;
1816 
1817 		flexcan_chip_interrupts_enable(dev);
1818 
1819 		netif_wake_queue(dev);
1820 		break;
1821 
1822 	default:
1823 		return -EOPNOTSUPP;
1824 	}
1825 
1826 	return 0;
1827 }
1828 
1829 static const struct net_device_ops flexcan_netdev_ops = {
1830 	.ndo_open	= flexcan_open,
1831 	.ndo_stop	= flexcan_close,
1832 	.ndo_start_xmit	= flexcan_start_xmit,
1833 	.ndo_change_mtu = can_change_mtu,
1834 };
1835 
1836 static int register_flexcandev(struct net_device *dev)
1837 {
1838 	struct flexcan_priv *priv = netdev_priv(dev);
1839 	struct flexcan_regs __iomem *regs = priv->regs;
1840 	u32 reg, err;
1841 
1842 	err = flexcan_clks_enable(priv);
1843 	if (err)
1844 		return err;
1845 
1846 	/* select "bus clock", chip must be disabled */
1847 	err = flexcan_chip_disable(priv);
1848 	if (err)
1849 		goto out_clks_disable;
1850 
1851 	reg = priv->read(&regs->ctrl);
1852 	if (priv->clk_src)
1853 		reg |= FLEXCAN_CTRL_CLK_SRC;
1854 	else
1855 		reg &= ~FLEXCAN_CTRL_CLK_SRC;
1856 	priv->write(reg, &regs->ctrl);
1857 
1858 	err = flexcan_chip_enable(priv);
1859 	if (err)
1860 		goto out_chip_disable;
1861 
1862 	/* set freeze, halt */
1863 	err = flexcan_chip_freeze(priv);
1864 	if (err)
1865 		goto out_chip_disable;
1866 
1867 	/* activate FIFO, restrict register access */
1868 	reg = priv->read(&regs->mcr);
1869 	reg |=  FLEXCAN_MCR_FEN | FLEXCAN_MCR_SUPV;
1870 	priv->write(reg, &regs->mcr);
1871 
1872 	/* Currently we only support newer versions of this core
1873 	 * featuring a RX hardware FIFO (although this driver doesn't
1874 	 * make use of it on some cores). Older cores, found on some
1875 	 * Coldfire derivates are not tested.
1876 	 */
1877 	reg = priv->read(&regs->mcr);
1878 	if (!(reg & FLEXCAN_MCR_FEN)) {
1879 		netdev_err(dev, "Could not enable RX FIFO, unsupported core\n");
1880 		err = -ENODEV;
1881 		goto out_chip_disable;
1882 	}
1883 
1884 	err = register_candev(dev);
1885 	if (err)
1886 		goto out_chip_disable;
1887 
1888 	/* Disable core and let pm_runtime_put() disable the clocks.
1889 	 * If CONFIG_PM is not enabled, the clocks will stay powered.
1890 	 */
1891 	flexcan_chip_disable(priv);
1892 	pm_runtime_put(priv->dev);
1893 
1894 	return 0;
1895 
1896  out_chip_disable:
1897 	flexcan_chip_disable(priv);
1898  out_clks_disable:
1899 	flexcan_clks_disable(priv);
1900 	return err;
1901 }
1902 
1903 static void unregister_flexcandev(struct net_device *dev)
1904 {
1905 	unregister_candev(dev);
1906 }
1907 
1908 static int flexcan_setup_stop_mode_gpr(struct platform_device *pdev)
1909 {
1910 	struct net_device *dev = platform_get_drvdata(pdev);
1911 	struct device_node *np = pdev->dev.of_node;
1912 	struct device_node *gpr_np;
1913 	struct flexcan_priv *priv;
1914 	phandle phandle;
1915 	u32 out_val[3];
1916 	int ret;
1917 
1918 	if (!np)
1919 		return -EINVAL;
1920 
1921 	/* stop mode property format is:
1922 	 * <&gpr req_gpr req_bit>.
1923 	 */
1924 	ret = of_property_read_u32_array(np, "fsl,stop-mode", out_val,
1925 					 ARRAY_SIZE(out_val));
1926 	if (ret) {
1927 		dev_dbg(&pdev->dev, "no stop-mode property\n");
1928 		return ret;
1929 	}
1930 	phandle = *out_val;
1931 
1932 	gpr_np = of_find_node_by_phandle(phandle);
1933 	if (!gpr_np) {
1934 		dev_dbg(&pdev->dev, "could not find gpr node by phandle\n");
1935 		return -ENODEV;
1936 	}
1937 
1938 	priv = netdev_priv(dev);
1939 	priv->stm.gpr = syscon_node_to_regmap(gpr_np);
1940 	if (IS_ERR(priv->stm.gpr)) {
1941 		dev_dbg(&pdev->dev, "could not find gpr regmap\n");
1942 		ret = PTR_ERR(priv->stm.gpr);
1943 		goto out_put_node;
1944 	}
1945 
1946 	priv->stm.req_gpr = out_val[1];
1947 	priv->stm.req_bit = out_val[2];
1948 
1949 	dev_dbg(&pdev->dev,
1950 		"gpr %s req_gpr=0x02%x req_bit=%u\n",
1951 		gpr_np->full_name, priv->stm.req_gpr, priv->stm.req_bit);
1952 
1953 	return 0;
1954 
1955 out_put_node:
1956 	of_node_put(gpr_np);
1957 	return ret;
1958 }
1959 
1960 static int flexcan_setup_stop_mode_scfw(struct platform_device *pdev)
1961 {
1962 	struct net_device *dev = platform_get_drvdata(pdev);
1963 	struct flexcan_priv *priv;
1964 	u8 scu_idx;
1965 	int ret;
1966 
1967 	ret = of_property_read_u8(pdev->dev.of_node, "fsl,scu-index", &scu_idx);
1968 	if (ret < 0) {
1969 		dev_dbg(&pdev->dev, "failed to get scu index\n");
1970 		return ret;
1971 	}
1972 
1973 	priv = netdev_priv(dev);
1974 	priv->scu_idx = scu_idx;
1975 
1976 	/* this function could be deferred probe, return -EPROBE_DEFER */
1977 	return imx_scu_get_handle(&priv->sc_ipc_handle);
1978 }
1979 
1980 /* flexcan_setup_stop_mode - Setup stop mode for wakeup
1981  *
1982  * Return: = 0 setup stop mode successfully or doesn't support this feature
1983  *         < 0 fail to setup stop mode (could be deferred probe)
1984  */
1985 static int flexcan_setup_stop_mode(struct platform_device *pdev)
1986 {
1987 	struct net_device *dev = platform_get_drvdata(pdev);
1988 	struct flexcan_priv *priv;
1989 	int ret;
1990 
1991 	priv = netdev_priv(dev);
1992 
1993 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW)
1994 		ret = flexcan_setup_stop_mode_scfw(pdev);
1995 	else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR)
1996 		ret = flexcan_setup_stop_mode_gpr(pdev);
1997 	else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_AUTO_STOP_MODE)
1998 		ret = 0;
1999 	else
2000 		/* return 0 directly if doesn't support stop mode feature */
2001 		return 0;
2002 
2003 	if (ret)
2004 		return ret;
2005 
2006 	device_set_wakeup_capable(&pdev->dev, true);
2007 
2008 	if (of_property_read_bool(pdev->dev.of_node, "wakeup-source"))
2009 		device_set_wakeup_enable(&pdev->dev, true);
2010 
2011 	return 0;
2012 }
2013 
2014 static const struct of_device_id flexcan_of_match[] = {
2015 	{ .compatible = "fsl,imx8qm-flexcan", .data = &fsl_imx8qm_devtype_data, },
2016 	{ .compatible = "fsl,imx8mp-flexcan", .data = &fsl_imx8mp_devtype_data, },
2017 	{ .compatible = "fsl,imx93-flexcan", .data = &fsl_imx93_devtype_data, },
2018 	{ .compatible = "fsl,imx6q-flexcan", .data = &fsl_imx6q_devtype_data, },
2019 	{ .compatible = "fsl,imx28-flexcan", .data = &fsl_imx28_devtype_data, },
2020 	{ .compatible = "fsl,imx53-flexcan", .data = &fsl_imx25_devtype_data, },
2021 	{ .compatible = "fsl,imx35-flexcan", .data = &fsl_imx25_devtype_data, },
2022 	{ .compatible = "fsl,imx25-flexcan", .data = &fsl_imx25_devtype_data, },
2023 	{ .compatible = "fsl,p1010-flexcan", .data = &fsl_p1010_devtype_data, },
2024 	{ .compatible = "fsl,vf610-flexcan", .data = &fsl_vf610_devtype_data, },
2025 	{ .compatible = "fsl,ls1021ar2-flexcan", .data = &fsl_ls1021a_r2_devtype_data, },
2026 	{ .compatible = "fsl,lx2160ar1-flexcan", .data = &fsl_lx2160a_r1_devtype_data, },
2027 	{ /* sentinel */ },
2028 };
2029 MODULE_DEVICE_TABLE(of, flexcan_of_match);
2030 
2031 static const struct platform_device_id flexcan_id_table[] = {
2032 	{
2033 		.name = "flexcan-mcf5441x",
2034 		.driver_data = (kernel_ulong_t)&fsl_mcf5441x_devtype_data,
2035 	}, {
2036 		/* sentinel */
2037 	},
2038 };
2039 MODULE_DEVICE_TABLE(platform, flexcan_id_table);
2040 
2041 static int flexcan_probe(struct platform_device *pdev)
2042 {
2043 	const struct of_device_id *of_id;
2044 	const struct flexcan_devtype_data *devtype_data;
2045 	struct net_device *dev;
2046 	struct flexcan_priv *priv;
2047 	struct regulator *reg_xceiver;
2048 	struct clk *clk_ipg = NULL, *clk_per = NULL;
2049 	struct flexcan_regs __iomem *regs;
2050 	struct flexcan_platform_data *pdata;
2051 	int err, irq;
2052 	u8 clk_src = 1;
2053 	u32 clock_freq = 0;
2054 
2055 	reg_xceiver = devm_regulator_get_optional(&pdev->dev, "xceiver");
2056 	if (PTR_ERR(reg_xceiver) == -EPROBE_DEFER)
2057 		return -EPROBE_DEFER;
2058 	else if (PTR_ERR(reg_xceiver) == -ENODEV)
2059 		reg_xceiver = NULL;
2060 	else if (IS_ERR(reg_xceiver))
2061 		return PTR_ERR(reg_xceiver);
2062 
2063 	if (pdev->dev.of_node) {
2064 		of_property_read_u32(pdev->dev.of_node,
2065 				     "clock-frequency", &clock_freq);
2066 		of_property_read_u8(pdev->dev.of_node,
2067 				    "fsl,clk-source", &clk_src);
2068 	} else {
2069 		pdata = dev_get_platdata(&pdev->dev);
2070 		if (pdata) {
2071 			clock_freq = pdata->clock_frequency;
2072 			clk_src = pdata->clk_src;
2073 		}
2074 	}
2075 
2076 	if (!clock_freq) {
2077 		clk_ipg = devm_clk_get(&pdev->dev, "ipg");
2078 		if (IS_ERR(clk_ipg)) {
2079 			dev_err(&pdev->dev, "no ipg clock defined\n");
2080 			return PTR_ERR(clk_ipg);
2081 		}
2082 
2083 		clk_per = devm_clk_get(&pdev->dev, "per");
2084 		if (IS_ERR(clk_per)) {
2085 			dev_err(&pdev->dev, "no per clock defined\n");
2086 			return PTR_ERR(clk_per);
2087 		}
2088 		clock_freq = clk_get_rate(clk_per);
2089 	}
2090 
2091 	irq = platform_get_irq(pdev, 0);
2092 	if (irq <= 0)
2093 		return -ENODEV;
2094 
2095 	regs = devm_platform_ioremap_resource(pdev, 0);
2096 	if (IS_ERR(regs))
2097 		return PTR_ERR(regs);
2098 
2099 	of_id = of_match_device(flexcan_of_match, &pdev->dev);
2100 	if (of_id)
2101 		devtype_data = of_id->data;
2102 	else if (platform_get_device_id(pdev)->driver_data)
2103 		devtype_data = (struct flexcan_devtype_data *)
2104 			platform_get_device_id(pdev)->driver_data;
2105 	else
2106 		return -ENODEV;
2107 
2108 	if ((devtype_data->quirks & FLEXCAN_QUIRK_SUPPORT_FD) &&
2109 	    !((devtype_data->quirks &
2110 	       (FLEXCAN_QUIRK_USE_RX_MAILBOX |
2111 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
2112 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR |
2113 		FLEXCAN_QUIRK_SUPPORT_RX_FIFO)) ==
2114 	      (FLEXCAN_QUIRK_USE_RX_MAILBOX |
2115 	       FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
2116 	       FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR))) {
2117 		dev_err(&pdev->dev, "CAN-FD mode doesn't work in RX-FIFO mode!\n");
2118 		return -EINVAL;
2119 	}
2120 
2121 	if ((devtype_data->quirks &
2122 	     (FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
2123 	      FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR)) ==
2124 	    FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR) {
2125 		dev_err(&pdev->dev,
2126 			"Quirks (0x%08x) inconsistent: RX_MAILBOX_RX supported but not RX_MAILBOX\n",
2127 			devtype_data->quirks);
2128 		return -EINVAL;
2129 	}
2130 
2131 	dev = alloc_candev(sizeof(struct flexcan_priv), 1);
2132 	if (!dev)
2133 		return -ENOMEM;
2134 
2135 	platform_set_drvdata(pdev, dev);
2136 	SET_NETDEV_DEV(dev, &pdev->dev);
2137 
2138 	dev->netdev_ops = &flexcan_netdev_ops;
2139 	dev->ethtool_ops = &flexcan_ethtool_ops;
2140 	dev->irq = irq;
2141 	dev->flags |= IFF_ECHO;
2142 
2143 	priv = netdev_priv(dev);
2144 	priv->devtype_data = *devtype_data;
2145 
2146 	if (of_property_read_bool(pdev->dev.of_node, "big-endian") ||
2147 	    priv->devtype_data.quirks & FLEXCAN_QUIRK_DEFAULT_BIG_ENDIAN) {
2148 		priv->read = flexcan_read_be;
2149 		priv->write = flexcan_write_be;
2150 	} else {
2151 		priv->read = flexcan_read_le;
2152 		priv->write = flexcan_write_le;
2153 	}
2154 
2155 	priv->dev = &pdev->dev;
2156 	priv->can.clock.freq = clock_freq;
2157 	priv->can.do_set_mode = flexcan_set_mode;
2158 	priv->can.do_get_berr_counter = flexcan_get_berr_counter;
2159 	priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
2160 		CAN_CTRLMODE_LISTENONLY	| CAN_CTRLMODE_3_SAMPLES |
2161 		CAN_CTRLMODE_BERR_REPORTING;
2162 	priv->regs = regs;
2163 	priv->clk_ipg = clk_ipg;
2164 	priv->clk_per = clk_per;
2165 	priv->clk_src = clk_src;
2166 	priv->reg_xceiver = reg_xceiver;
2167 
2168 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_NR_IRQ_3) {
2169 		priv->irq_boff = platform_get_irq(pdev, 1);
2170 		if (priv->irq_boff <= 0) {
2171 			err = -ENODEV;
2172 			goto failed_platform_get_irq;
2173 		}
2174 		priv->irq_err = platform_get_irq(pdev, 2);
2175 		if (priv->irq_err <= 0) {
2176 			err = -ENODEV;
2177 			goto failed_platform_get_irq;
2178 		}
2179 	}
2180 
2181 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SUPPORT_FD) {
2182 		priv->can.ctrlmode_supported |= CAN_CTRLMODE_FD |
2183 			CAN_CTRLMODE_FD_NON_ISO;
2184 		priv->can.bittiming_const = &flexcan_fd_bittiming_const;
2185 		priv->can.data_bittiming_const =
2186 			&flexcan_fd_data_bittiming_const;
2187 	} else {
2188 		priv->can.bittiming_const = &flexcan_bittiming_const;
2189 	}
2190 
2191 	pm_runtime_get_noresume(&pdev->dev);
2192 	pm_runtime_set_active(&pdev->dev);
2193 	pm_runtime_enable(&pdev->dev);
2194 
2195 	err = register_flexcandev(dev);
2196 	if (err) {
2197 		dev_err(&pdev->dev, "registering netdev failed\n");
2198 		goto failed_register;
2199 	}
2200 
2201 	err = flexcan_setup_stop_mode(pdev);
2202 	if (err < 0) {
2203 		dev_err_probe(&pdev->dev, err, "setup stop mode failed\n");
2204 		goto failed_setup_stop_mode;
2205 	}
2206 
2207 	of_can_transceiver(dev);
2208 
2209 	return 0;
2210 
2211  failed_setup_stop_mode:
2212 	unregister_flexcandev(dev);
2213  failed_register:
2214 	pm_runtime_put_noidle(&pdev->dev);
2215 	pm_runtime_disable(&pdev->dev);
2216  failed_platform_get_irq:
2217 	free_candev(dev);
2218 	return err;
2219 }
2220 
2221 static int flexcan_remove(struct platform_device *pdev)
2222 {
2223 	struct net_device *dev = platform_get_drvdata(pdev);
2224 
2225 	device_set_wakeup_enable(&pdev->dev, false);
2226 	device_set_wakeup_capable(&pdev->dev, false);
2227 	unregister_flexcandev(dev);
2228 	pm_runtime_disable(&pdev->dev);
2229 	free_candev(dev);
2230 
2231 	return 0;
2232 }
2233 
2234 static int __maybe_unused flexcan_suspend(struct device *device)
2235 {
2236 	struct net_device *dev = dev_get_drvdata(device);
2237 	struct flexcan_priv *priv = netdev_priv(dev);
2238 	int err;
2239 
2240 	if (netif_running(dev)) {
2241 		/* if wakeup is enabled, enter stop mode
2242 		 * else enter disabled mode.
2243 		 */
2244 		if (device_may_wakeup(device)) {
2245 			enable_irq_wake(dev->irq);
2246 			err = flexcan_enter_stop_mode(priv);
2247 			if (err)
2248 				return err;
2249 		} else {
2250 			err = flexcan_chip_stop(dev);
2251 			if (err)
2252 				return err;
2253 
2254 			flexcan_chip_interrupts_disable(dev);
2255 
2256 			err = pinctrl_pm_select_sleep_state(device);
2257 			if (err)
2258 				return err;
2259 		}
2260 		netif_stop_queue(dev);
2261 		netif_device_detach(dev);
2262 	}
2263 	priv->can.state = CAN_STATE_SLEEPING;
2264 
2265 	return 0;
2266 }
2267 
2268 static int __maybe_unused flexcan_resume(struct device *device)
2269 {
2270 	struct net_device *dev = dev_get_drvdata(device);
2271 	struct flexcan_priv *priv = netdev_priv(dev);
2272 	int err;
2273 
2274 	priv->can.state = CAN_STATE_ERROR_ACTIVE;
2275 	if (netif_running(dev)) {
2276 		netif_device_attach(dev);
2277 		netif_start_queue(dev);
2278 		if (device_may_wakeup(device)) {
2279 			disable_irq_wake(dev->irq);
2280 			err = flexcan_exit_stop_mode(priv);
2281 			if (err)
2282 				return err;
2283 		} else {
2284 			err = pinctrl_pm_select_default_state(device);
2285 			if (err)
2286 				return err;
2287 
2288 			err = flexcan_chip_start(dev);
2289 			if (err)
2290 				return err;
2291 
2292 			flexcan_chip_interrupts_enable(dev);
2293 		}
2294 	}
2295 
2296 	return 0;
2297 }
2298 
2299 static int __maybe_unused flexcan_runtime_suspend(struct device *device)
2300 {
2301 	struct net_device *dev = dev_get_drvdata(device);
2302 	struct flexcan_priv *priv = netdev_priv(dev);
2303 
2304 	flexcan_clks_disable(priv);
2305 
2306 	return 0;
2307 }
2308 
2309 static int __maybe_unused flexcan_runtime_resume(struct device *device)
2310 {
2311 	struct net_device *dev = dev_get_drvdata(device);
2312 	struct flexcan_priv *priv = netdev_priv(dev);
2313 
2314 	return flexcan_clks_enable(priv);
2315 }
2316 
2317 static int __maybe_unused flexcan_noirq_suspend(struct device *device)
2318 {
2319 	struct net_device *dev = dev_get_drvdata(device);
2320 	struct flexcan_priv *priv = netdev_priv(dev);
2321 
2322 	if (netif_running(dev)) {
2323 		int err;
2324 
2325 		if (device_may_wakeup(device)) {
2326 			flexcan_enable_wakeup_irq(priv, true);
2327 			/* For auto stop mode, need to keep the clock on before
2328 			 * system go into low power mode. After system go into
2329 			 * low power mode, hardware will config the flexcan into
2330 			 * stop mode, and gate off the clock automatically.
2331 			 */
2332 			if (priv->devtype_data.quirks & FLEXCAN_QUIRK_AUTO_STOP_MODE)
2333 				return 0;
2334 		}
2335 
2336 		err = pm_runtime_force_suspend(device);
2337 		if (err)
2338 			return err;
2339 	}
2340 
2341 	return 0;
2342 }
2343 
2344 static int __maybe_unused flexcan_noirq_resume(struct device *device)
2345 {
2346 	struct net_device *dev = dev_get_drvdata(device);
2347 	struct flexcan_priv *priv = netdev_priv(dev);
2348 
2349 	if (netif_running(dev)) {
2350 		int err;
2351 
2352 		/* For the wakeup in auto stop mode, no need to gate on the
2353 		 * clock here, hardware will do this automatically.
2354 		 */
2355 		if (!(device_may_wakeup(device) &&
2356 		      priv->devtype_data.quirks & FLEXCAN_QUIRK_AUTO_STOP_MODE)) {
2357 			err = pm_runtime_force_resume(device);
2358 			if (err)
2359 				return err;
2360 		}
2361 
2362 		if (device_may_wakeup(device))
2363 			flexcan_enable_wakeup_irq(priv, false);
2364 	}
2365 
2366 	return 0;
2367 }
2368 
2369 static const struct dev_pm_ops flexcan_pm_ops = {
2370 	SET_SYSTEM_SLEEP_PM_OPS(flexcan_suspend, flexcan_resume)
2371 	SET_RUNTIME_PM_OPS(flexcan_runtime_suspend, flexcan_runtime_resume, NULL)
2372 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(flexcan_noirq_suspend, flexcan_noirq_resume)
2373 };
2374 
2375 static struct platform_driver flexcan_driver = {
2376 	.driver = {
2377 		.name = DRV_NAME,
2378 		.pm = &flexcan_pm_ops,
2379 		.of_match_table = flexcan_of_match,
2380 	},
2381 	.probe = flexcan_probe,
2382 	.remove = flexcan_remove,
2383 	.id_table = flexcan_id_table,
2384 };
2385 
2386 module_platform_driver(flexcan_driver);
2387 
2388 MODULE_AUTHOR("Sascha Hauer <kernel@pengutronix.de>, "
2389 	      "Marc Kleine-Budde <kernel@pengutronix.de>");
2390 MODULE_LICENSE("GPL v2");
2391 MODULE_DESCRIPTION("CAN port driver for flexcan based chip");
2392