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 <[email protected]>
8 // Copyright (c) 2014 David Jander, Protonic Holland
9 //
10 // Based on code originally by Andrey Volkov <[email protected]>
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/pinctrl/consumer.h>
27 #include <linux/platform_device.h>
28 #include <linux/can/platform/flexcan.h>
29 #include <linux/pm_runtime.h>
30 #include <linux/property.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_SETUP_STOP_MODE_GPR |
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_imx95_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_FD |
361 		FLEXCAN_QUIRK_SUPPORT_ECC | FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
362 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR | FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI,
363 };
364 
365 static const struct flexcan_devtype_data fsl_vf610_devtype_data = {
366 	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
367 		FLEXCAN_QUIRK_DISABLE_MECR | FLEXCAN_QUIRK_USE_RX_MAILBOX |
368 		FLEXCAN_QUIRK_BROKEN_PERR_STATE | FLEXCAN_QUIRK_SUPPORT_ECC |
369 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
370 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR,
371 };
372 
373 static const struct flexcan_devtype_data fsl_ls1021a_r2_devtype_data = {
374 	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
375 		FLEXCAN_QUIRK_BROKEN_PERR_STATE | FLEXCAN_QUIRK_USE_RX_MAILBOX |
376 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
377 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR,
378 };
379 
380 static const struct flexcan_devtype_data fsl_lx2160a_r1_devtype_data = {
381 	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
382 		FLEXCAN_QUIRK_DISABLE_MECR | FLEXCAN_QUIRK_BROKEN_PERR_STATE |
383 		FLEXCAN_QUIRK_USE_RX_MAILBOX | FLEXCAN_QUIRK_SUPPORT_FD |
384 		FLEXCAN_QUIRK_SUPPORT_ECC |
385 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
386 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR,
387 };
388 
389 static const struct flexcan_devtype_data nxp_s32g2_devtype_data = {
390 	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
391 		FLEXCAN_QUIRK_DISABLE_MECR | FLEXCAN_QUIRK_BROKEN_PERR_STATE |
392 		FLEXCAN_QUIRK_USE_RX_MAILBOX | FLEXCAN_QUIRK_SUPPORT_FD |
393 		FLEXCAN_QUIRK_SUPPORT_ECC | FLEXCAN_QUIRK_NR_IRQ_3 |
394 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
395 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR |
396 		FLEXCAN_QUIRK_SECONDARY_MB_IRQ,
397 };
398 
399 static const struct can_bittiming_const flexcan_bittiming_const = {
400 	.name = DRV_NAME,
401 	.tseg1_min = 4,
402 	.tseg1_max = 16,
403 	.tseg2_min = 2,
404 	.tseg2_max = 8,
405 	.sjw_max = 4,
406 	.brp_min = 1,
407 	.brp_max = 256,
408 	.brp_inc = 1,
409 };
410 
411 static const struct can_bittiming_const flexcan_fd_bittiming_const = {
412 	.name = DRV_NAME,
413 	.tseg1_min = 2,
414 	.tseg1_max = 96,
415 	.tseg2_min = 2,
416 	.tseg2_max = 32,
417 	.sjw_max = 16,
418 	.brp_min = 1,
419 	.brp_max = 1024,
420 	.brp_inc = 1,
421 };
422 
423 static const struct can_bittiming_const flexcan_fd_data_bittiming_const = {
424 	.name = DRV_NAME,
425 	.tseg1_min = 2,
426 	.tseg1_max = 39,
427 	.tseg2_min = 2,
428 	.tseg2_max = 8,
429 	.sjw_max = 4,
430 	.brp_min = 1,
431 	.brp_max = 1024,
432 	.brp_inc = 1,
433 };
434 
435 /* FlexCAN module is essentially modelled as a little-endian IP in most
436  * SoCs, i.e the registers as well as the message buffer areas are
437  * implemented in a little-endian fashion.
438  *
439  * However there are some SoCs (e.g. LS1021A) which implement the FlexCAN
440  * module in a big-endian fashion (i.e the registers as well as the
441  * message buffer areas are implemented in a big-endian way).
442  *
443  * In addition, the FlexCAN module can be found on SoCs having ARM or
444  * PPC cores. So, we need to abstract off the register read/write
445  * functions, ensuring that these cater to all the combinations of module
446  * endianness and underlying CPU endianness.
447  */
flexcan_read_be(void __iomem * addr)448 static inline u32 flexcan_read_be(void __iomem *addr)
449 {
450 	return ioread32be(addr);
451 }
452 
flexcan_write_be(u32 val,void __iomem * addr)453 static inline void flexcan_write_be(u32 val, void __iomem *addr)
454 {
455 	iowrite32be(val, addr);
456 }
457 
flexcan_read_le(void __iomem * addr)458 static inline u32 flexcan_read_le(void __iomem *addr)
459 {
460 	return ioread32(addr);
461 }
462 
flexcan_write_le(u32 val,void __iomem * addr)463 static inline void flexcan_write_le(u32 val, void __iomem *addr)
464 {
465 	iowrite32(val, addr);
466 }
467 
flexcan_get_mb(const struct flexcan_priv * priv,u8 mb_index)468 static struct flexcan_mb __iomem *flexcan_get_mb(const struct flexcan_priv *priv,
469 						 u8 mb_index)
470 {
471 	u8 bank_size;
472 	bool bank;
473 
474 	if (WARN_ON(mb_index >= priv->mb_count))
475 		return NULL;
476 
477 	bank_size = sizeof(priv->regs->mb[0]) / priv->mb_size;
478 
479 	bank = mb_index >= bank_size;
480 	if (bank)
481 		mb_index -= bank_size;
482 
483 	return (struct flexcan_mb __iomem *)
484 		(&priv->regs->mb[bank][priv->mb_size * mb_index]);
485 }
486 
flexcan_low_power_enter_ack(struct flexcan_priv * priv)487 static int flexcan_low_power_enter_ack(struct flexcan_priv *priv)
488 {
489 	struct flexcan_regs __iomem *regs = priv->regs;
490 	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
491 
492 	while (timeout-- && !(priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
493 		udelay(10);
494 
495 	if (!(priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
496 		return -ETIMEDOUT;
497 
498 	return 0;
499 }
500 
flexcan_low_power_exit_ack(struct flexcan_priv * priv)501 static int flexcan_low_power_exit_ack(struct flexcan_priv *priv)
502 {
503 	struct flexcan_regs __iomem *regs = priv->regs;
504 	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
505 
506 	while (timeout-- && (priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
507 		udelay(10);
508 
509 	if (priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK)
510 		return -ETIMEDOUT;
511 
512 	return 0;
513 }
514 
flexcan_enable_wakeup_irq(struct flexcan_priv * priv,bool enable)515 static void flexcan_enable_wakeup_irq(struct flexcan_priv *priv, bool enable)
516 {
517 	struct flexcan_regs __iomem *regs = priv->regs;
518 	u32 reg_mcr;
519 
520 	reg_mcr = priv->read(&regs->mcr);
521 
522 	if (enable)
523 		reg_mcr |= FLEXCAN_MCR_WAK_MSK;
524 	else
525 		reg_mcr &= ~FLEXCAN_MCR_WAK_MSK;
526 
527 	priv->write(reg_mcr, &regs->mcr);
528 }
529 
flexcan_stop_mode_enable_scfw(struct flexcan_priv * priv,bool enabled)530 static int flexcan_stop_mode_enable_scfw(struct flexcan_priv *priv, bool enabled)
531 {
532 	u8 idx = priv->scu_idx;
533 	u32 rsrc_id, val;
534 
535 	rsrc_id = IMX_SC_R_CAN(idx);
536 
537 	if (enabled)
538 		val = 1;
539 	else
540 		val = 0;
541 
542 	/* stop mode request via scu firmware */
543 	return imx_sc_misc_set_control(priv->sc_ipc_handle, rsrc_id,
544 				       IMX_SC_C_IPG_STOP, val);
545 }
546 
flexcan_enter_stop_mode(struct flexcan_priv * priv)547 static inline int flexcan_enter_stop_mode(struct flexcan_priv *priv)
548 {
549 	struct flexcan_regs __iomem *regs = priv->regs;
550 	u32 reg_mcr;
551 	int ret;
552 
553 	reg_mcr = priv->read(&regs->mcr);
554 	reg_mcr |= FLEXCAN_MCR_SLF_WAK;
555 	priv->write(reg_mcr, &regs->mcr);
556 
557 	/* enable stop request */
558 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW) {
559 		ret = flexcan_stop_mode_enable_scfw(priv, true);
560 		if (ret < 0)
561 			return ret;
562 	} else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR) {
563 		regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr,
564 				   1 << priv->stm.req_bit, 1 << priv->stm.req_bit);
565 	} else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI) {
566 		/* For the SCMI mode, driver do nothing, ATF will send request to
567 		 * SM(system manager, M33 core) through SCMI protocol after linux
568 		 * suspend. Once SM get this request, it will send IPG_STOP signal
569 		 * to Flex_CAN, let CAN in STOP mode.
570 		 */
571 		return 0;
572 	}
573 
574 	return flexcan_low_power_enter_ack(priv);
575 }
576 
flexcan_exit_stop_mode(struct flexcan_priv * priv)577 static inline int flexcan_exit_stop_mode(struct flexcan_priv *priv)
578 {
579 	struct flexcan_regs __iomem *regs = priv->regs;
580 	u32 reg_mcr;
581 	int ret;
582 
583 	/* Remove stop request, for FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI,
584 	 * do nothing here, because ATF already send request to SM before
585 	 * linux resume. Once SM get this request, it will deassert the
586 	 * IPG_STOP signal to Flex_CAN.
587 	 */
588 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW) {
589 		ret = flexcan_stop_mode_enable_scfw(priv, false);
590 		if (ret < 0)
591 			return ret;
592 	} else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR) {
593 		regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr,
594 				   1 << priv->stm.req_bit, 0);
595 	}
596 
597 	reg_mcr = priv->read(&regs->mcr);
598 	reg_mcr &= ~FLEXCAN_MCR_SLF_WAK;
599 	priv->write(reg_mcr, &regs->mcr);
600 
601 	return flexcan_low_power_exit_ack(priv);
602 }
603 
flexcan_error_irq_enable(const struct flexcan_priv * priv)604 static inline void flexcan_error_irq_enable(const struct flexcan_priv *priv)
605 {
606 	struct flexcan_regs __iomem *regs = priv->regs;
607 	u32 reg_ctrl = (priv->reg_ctrl_default | FLEXCAN_CTRL_ERR_MSK);
608 
609 	priv->write(reg_ctrl, &regs->ctrl);
610 }
611 
flexcan_error_irq_disable(const struct flexcan_priv * priv)612 static inline void flexcan_error_irq_disable(const struct flexcan_priv *priv)
613 {
614 	struct flexcan_regs __iomem *regs = priv->regs;
615 	u32 reg_ctrl = (priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_MSK);
616 
617 	priv->write(reg_ctrl, &regs->ctrl);
618 }
619 
flexcan_clks_enable(const struct flexcan_priv * priv)620 static int flexcan_clks_enable(const struct flexcan_priv *priv)
621 {
622 	int err = 0;
623 
624 	if (priv->clk_ipg) {
625 		err = clk_prepare_enable(priv->clk_ipg);
626 		if (err)
627 			return err;
628 	}
629 
630 	if (priv->clk_per) {
631 		err = clk_prepare_enable(priv->clk_per);
632 		if (err)
633 			clk_disable_unprepare(priv->clk_ipg);
634 	}
635 
636 	return err;
637 }
638 
flexcan_clks_disable(const struct flexcan_priv * priv)639 static void flexcan_clks_disable(const struct flexcan_priv *priv)
640 {
641 	clk_disable_unprepare(priv->clk_per);
642 	clk_disable_unprepare(priv->clk_ipg);
643 }
644 
flexcan_transceiver_enable(const struct flexcan_priv * priv)645 static inline int flexcan_transceiver_enable(const struct flexcan_priv *priv)
646 {
647 	if (!priv->reg_xceiver)
648 		return 0;
649 
650 	return regulator_enable(priv->reg_xceiver);
651 }
652 
flexcan_transceiver_disable(const struct flexcan_priv * priv)653 static inline int flexcan_transceiver_disable(const struct flexcan_priv *priv)
654 {
655 	if (!priv->reg_xceiver)
656 		return 0;
657 
658 	return regulator_disable(priv->reg_xceiver);
659 }
660 
flexcan_chip_enable(struct flexcan_priv * priv)661 static int flexcan_chip_enable(struct flexcan_priv *priv)
662 {
663 	struct flexcan_regs __iomem *regs = priv->regs;
664 	u32 reg;
665 
666 	reg = priv->read(&regs->mcr);
667 	reg &= ~FLEXCAN_MCR_MDIS;
668 	priv->write(reg, &regs->mcr);
669 
670 	return flexcan_low_power_exit_ack(priv);
671 }
672 
flexcan_chip_disable(struct flexcan_priv * priv)673 static int flexcan_chip_disable(struct flexcan_priv *priv)
674 {
675 	struct flexcan_regs __iomem *regs = priv->regs;
676 	u32 reg;
677 
678 	reg = priv->read(&regs->mcr);
679 	reg |= FLEXCAN_MCR_MDIS;
680 	priv->write(reg, &regs->mcr);
681 
682 	return flexcan_low_power_enter_ack(priv);
683 }
684 
flexcan_chip_freeze(struct flexcan_priv * priv)685 static int flexcan_chip_freeze(struct flexcan_priv *priv)
686 {
687 	struct flexcan_regs __iomem *regs = priv->regs;
688 	unsigned int timeout;
689 	u32 bitrate = priv->can.bittiming.bitrate;
690 	u32 reg;
691 
692 	if (bitrate)
693 		timeout = 1000 * 1000 * 10 / bitrate;
694 	else
695 		timeout = FLEXCAN_TIMEOUT_US / 10;
696 
697 	reg = priv->read(&regs->mcr);
698 	reg |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_HALT;
699 	priv->write(reg, &regs->mcr);
700 
701 	while (timeout-- && !(priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
702 		udelay(100);
703 
704 	if (!(priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
705 		return -ETIMEDOUT;
706 
707 	return 0;
708 }
709 
flexcan_chip_unfreeze(struct flexcan_priv * priv)710 static int flexcan_chip_unfreeze(struct flexcan_priv *priv)
711 {
712 	struct flexcan_regs __iomem *regs = priv->regs;
713 	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
714 	u32 reg;
715 
716 	reg = priv->read(&regs->mcr);
717 	reg &= ~FLEXCAN_MCR_HALT;
718 	priv->write(reg, &regs->mcr);
719 
720 	while (timeout-- && (priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
721 		udelay(10);
722 
723 	if (priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK)
724 		return -ETIMEDOUT;
725 
726 	return 0;
727 }
728 
flexcan_chip_softreset(struct flexcan_priv * priv)729 static int flexcan_chip_softreset(struct flexcan_priv *priv)
730 {
731 	struct flexcan_regs __iomem *regs = priv->regs;
732 	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
733 
734 	priv->write(FLEXCAN_MCR_SOFTRST, &regs->mcr);
735 	while (timeout-- && (priv->read(&regs->mcr) & FLEXCAN_MCR_SOFTRST))
736 		udelay(10);
737 
738 	if (priv->read(&regs->mcr) & FLEXCAN_MCR_SOFTRST)
739 		return -ETIMEDOUT;
740 
741 	return 0;
742 }
743 
__flexcan_get_berr_counter(const struct net_device * dev,struct can_berr_counter * bec)744 static int __flexcan_get_berr_counter(const struct net_device *dev,
745 				      struct can_berr_counter *bec)
746 {
747 	const struct flexcan_priv *priv = netdev_priv(dev);
748 	struct flexcan_regs __iomem *regs = priv->regs;
749 	u32 reg = priv->read(&regs->ecr);
750 
751 	bec->txerr = (reg >> 0) & 0xff;
752 	bec->rxerr = (reg >> 8) & 0xff;
753 
754 	return 0;
755 }
756 
flexcan_get_berr_counter(const struct net_device * dev,struct can_berr_counter * bec)757 static int flexcan_get_berr_counter(const struct net_device *dev,
758 				    struct can_berr_counter *bec)
759 {
760 	const struct flexcan_priv *priv = netdev_priv(dev);
761 	int err;
762 
763 	err = pm_runtime_resume_and_get(priv->dev);
764 	if (err < 0)
765 		return err;
766 
767 	err = __flexcan_get_berr_counter(dev, bec);
768 
769 	pm_runtime_put(priv->dev);
770 
771 	return err;
772 }
773 
flexcan_start_xmit(struct sk_buff * skb,struct net_device * dev)774 static netdev_tx_t flexcan_start_xmit(struct sk_buff *skb, struct net_device *dev)
775 {
776 	const struct flexcan_priv *priv = netdev_priv(dev);
777 	struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
778 	u32 can_id;
779 	u32 data;
780 	u32 ctrl = FLEXCAN_MB_CODE_TX_DATA | ((can_fd_len2dlc(cfd->len)) << 16);
781 	int i;
782 
783 	if (can_dev_dropped_skb(dev, skb))
784 		return NETDEV_TX_OK;
785 
786 	netif_stop_queue(dev);
787 
788 	if (cfd->can_id & CAN_EFF_FLAG) {
789 		can_id = cfd->can_id & CAN_EFF_MASK;
790 		ctrl |= FLEXCAN_MB_CNT_IDE | FLEXCAN_MB_CNT_SRR;
791 	} else {
792 		can_id = (cfd->can_id & CAN_SFF_MASK) << 18;
793 	}
794 
795 	if (cfd->can_id & CAN_RTR_FLAG)
796 		ctrl |= FLEXCAN_MB_CNT_RTR;
797 
798 	if (can_is_canfd_skb(skb)) {
799 		ctrl |= FLEXCAN_MB_CNT_EDL;
800 
801 		if (cfd->flags & CANFD_BRS)
802 			ctrl |= FLEXCAN_MB_CNT_BRS;
803 	}
804 
805 	for (i = 0; i < cfd->len; i += sizeof(u32)) {
806 		data = be32_to_cpup((__be32 *)&cfd->data[i]);
807 		priv->write(data, &priv->tx_mb->data[i / sizeof(u32)]);
808 	}
809 
810 	can_put_echo_skb(skb, dev, 0, 0);
811 
812 	priv->write(can_id, &priv->tx_mb->can_id);
813 	priv->write(ctrl, &priv->tx_mb->can_ctrl);
814 
815 	/* Errata ERR005829 step8:
816 	 * Write twice INACTIVE(0x8) code to first MB.
817 	 */
818 	priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
819 		    &priv->tx_mb_reserved->can_ctrl);
820 	priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
821 		    &priv->tx_mb_reserved->can_ctrl);
822 
823 	return NETDEV_TX_OK;
824 }
825 
flexcan_irq_bus_err(struct net_device * dev,u32 reg_esr)826 static void flexcan_irq_bus_err(struct net_device *dev, u32 reg_esr)
827 {
828 	struct flexcan_priv *priv = netdev_priv(dev);
829 	struct flexcan_regs __iomem *regs = priv->regs;
830 	struct sk_buff *skb;
831 	struct can_frame *cf;
832 	bool rx_errors = false, tx_errors = false;
833 	u32 timestamp;
834 	int err;
835 
836 	timestamp = priv->read(&regs->timer) << 16;
837 
838 	skb = alloc_can_err_skb(dev, &cf);
839 	if (unlikely(!skb))
840 		return;
841 
842 	cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
843 
844 	if (reg_esr & FLEXCAN_ESR_BIT1_ERR) {
845 		netdev_dbg(dev, "BIT1_ERR irq\n");
846 		cf->data[2] |= CAN_ERR_PROT_BIT1;
847 		tx_errors = true;
848 	}
849 	if (reg_esr & FLEXCAN_ESR_BIT0_ERR) {
850 		netdev_dbg(dev, "BIT0_ERR irq\n");
851 		cf->data[2] |= CAN_ERR_PROT_BIT0;
852 		tx_errors = true;
853 	}
854 	if (reg_esr & FLEXCAN_ESR_ACK_ERR) {
855 		netdev_dbg(dev, "ACK_ERR irq\n");
856 		cf->can_id |= CAN_ERR_ACK;
857 		cf->data[3] = CAN_ERR_PROT_LOC_ACK;
858 		tx_errors = true;
859 	}
860 	if (reg_esr & FLEXCAN_ESR_CRC_ERR) {
861 		netdev_dbg(dev, "CRC_ERR irq\n");
862 		cf->data[2] |= CAN_ERR_PROT_BIT;
863 		cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
864 		rx_errors = true;
865 	}
866 	if (reg_esr & FLEXCAN_ESR_FRM_ERR) {
867 		netdev_dbg(dev, "FRM_ERR irq\n");
868 		cf->data[2] |= CAN_ERR_PROT_FORM;
869 		rx_errors = true;
870 	}
871 	if (reg_esr & FLEXCAN_ESR_STF_ERR) {
872 		netdev_dbg(dev, "STF_ERR irq\n");
873 		cf->data[2] |= CAN_ERR_PROT_STUFF;
874 		rx_errors = true;
875 	}
876 
877 	priv->can.can_stats.bus_error++;
878 	if (rx_errors)
879 		dev->stats.rx_errors++;
880 	if (tx_errors)
881 		dev->stats.tx_errors++;
882 
883 	err = can_rx_offload_queue_timestamp(&priv->offload, skb, timestamp);
884 	if (err)
885 		dev->stats.rx_fifo_errors++;
886 }
887 
flexcan_irq_state(struct net_device * dev,u32 reg_esr)888 static void flexcan_irq_state(struct net_device *dev, u32 reg_esr)
889 {
890 	struct flexcan_priv *priv = netdev_priv(dev);
891 	struct flexcan_regs __iomem *regs = priv->regs;
892 	struct sk_buff *skb;
893 	struct can_frame *cf;
894 	enum can_state new_state, rx_state, tx_state;
895 	int flt;
896 	struct can_berr_counter bec;
897 	u32 timestamp;
898 	int err;
899 
900 	flt = reg_esr & FLEXCAN_ESR_FLT_CONF_MASK;
901 	if (likely(flt == FLEXCAN_ESR_FLT_CONF_ACTIVE)) {
902 		tx_state = unlikely(reg_esr & FLEXCAN_ESR_TX_WRN) ?
903 			CAN_STATE_ERROR_WARNING : CAN_STATE_ERROR_ACTIVE;
904 		rx_state = unlikely(reg_esr & FLEXCAN_ESR_RX_WRN) ?
905 			CAN_STATE_ERROR_WARNING : CAN_STATE_ERROR_ACTIVE;
906 		new_state = max(tx_state, rx_state);
907 	} else {
908 		__flexcan_get_berr_counter(dev, &bec);
909 		new_state = flt == FLEXCAN_ESR_FLT_CONF_PASSIVE ?
910 			CAN_STATE_ERROR_PASSIVE : CAN_STATE_BUS_OFF;
911 		rx_state = bec.rxerr >= bec.txerr ? new_state : 0;
912 		tx_state = bec.rxerr <= bec.txerr ? new_state : 0;
913 	}
914 
915 	/* state hasn't changed */
916 	if (likely(new_state == priv->can.state))
917 		return;
918 
919 	timestamp = priv->read(&regs->timer) << 16;
920 
921 	skb = alloc_can_err_skb(dev, &cf);
922 	if (unlikely(!skb))
923 		return;
924 
925 	can_change_state(dev, cf, tx_state, rx_state);
926 
927 	if (unlikely(new_state == CAN_STATE_BUS_OFF))
928 		can_bus_off(dev);
929 
930 	err = can_rx_offload_queue_timestamp(&priv->offload, skb, timestamp);
931 	if (err)
932 		dev->stats.rx_fifo_errors++;
933 }
934 
flexcan_read64_mask(struct flexcan_priv * priv,void __iomem * addr,u64 mask)935 static inline u64 flexcan_read64_mask(struct flexcan_priv *priv, void __iomem *addr, u64 mask)
936 {
937 	u64 reg = 0;
938 
939 	if (upper_32_bits(mask))
940 		reg = (u64)priv->read(addr - 4) << 32;
941 	if (lower_32_bits(mask))
942 		reg |= priv->read(addr);
943 
944 	return reg & mask;
945 }
946 
flexcan_write64(struct flexcan_priv * priv,u64 val,void __iomem * addr)947 static inline void flexcan_write64(struct flexcan_priv *priv, u64 val, void __iomem *addr)
948 {
949 	if (upper_32_bits(val))
950 		priv->write(upper_32_bits(val), addr - 4);
951 	if (lower_32_bits(val))
952 		priv->write(lower_32_bits(val), addr);
953 }
954 
flexcan_read_reg_iflag_rx(struct flexcan_priv * priv)955 static inline u64 flexcan_read_reg_iflag_rx(struct flexcan_priv *priv)
956 {
957 	return flexcan_read64_mask(priv, &priv->regs->iflag1, priv->rx_mask);
958 }
959 
flexcan_read_reg_iflag_tx(struct flexcan_priv * priv)960 static inline u64 flexcan_read_reg_iflag_tx(struct flexcan_priv *priv)
961 {
962 	return flexcan_read64_mask(priv, &priv->regs->iflag1, priv->tx_mask);
963 }
964 
rx_offload_to_priv(struct can_rx_offload * offload)965 static inline struct flexcan_priv *rx_offload_to_priv(struct can_rx_offload *offload)
966 {
967 	return container_of(offload, struct flexcan_priv, offload);
968 }
969 
flexcan_mailbox_read(struct can_rx_offload * offload,unsigned int n,u32 * timestamp,bool drop)970 static struct sk_buff *flexcan_mailbox_read(struct can_rx_offload *offload,
971 					    unsigned int n, u32 *timestamp,
972 					    bool drop)
973 {
974 	struct flexcan_priv *priv = rx_offload_to_priv(offload);
975 	struct flexcan_regs __iomem *regs = priv->regs;
976 	struct flexcan_mb __iomem *mb;
977 	struct sk_buff *skb;
978 	struct canfd_frame *cfd;
979 	u32 reg_ctrl, reg_id, reg_iflag1;
980 	int i;
981 
982 	mb = flexcan_get_mb(priv, n);
983 
984 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX) {
985 		u32 code;
986 
987 		do {
988 			reg_ctrl = priv->read(&mb->can_ctrl);
989 		} while (reg_ctrl & FLEXCAN_MB_CODE_RX_BUSY_BIT);
990 
991 		/* is this MB empty? */
992 		code = reg_ctrl & FLEXCAN_MB_CODE_MASK;
993 		if ((code != FLEXCAN_MB_CODE_RX_FULL) &&
994 		    (code != FLEXCAN_MB_CODE_RX_OVERRUN))
995 			return NULL;
996 
997 		if (code == FLEXCAN_MB_CODE_RX_OVERRUN) {
998 			/* This MB was overrun, we lost data */
999 			offload->dev->stats.rx_over_errors++;
1000 			offload->dev->stats.rx_errors++;
1001 		}
1002 	} else {
1003 		reg_iflag1 = priv->read(&regs->iflag1);
1004 		if (!(reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE))
1005 			return NULL;
1006 
1007 		reg_ctrl = priv->read(&mb->can_ctrl);
1008 	}
1009 
1010 	if (unlikely(drop)) {
1011 		skb = ERR_PTR(-ENOBUFS);
1012 		goto mark_as_read;
1013 	}
1014 
1015 	if (reg_ctrl & FLEXCAN_MB_CNT_EDL)
1016 		skb = alloc_canfd_skb(offload->dev, &cfd);
1017 	else
1018 		skb = alloc_can_skb(offload->dev, (struct can_frame **)&cfd);
1019 	if (unlikely(!skb)) {
1020 		skb = ERR_PTR(-ENOMEM);
1021 		goto mark_as_read;
1022 	}
1023 
1024 	/* increase timstamp to full 32 bit */
1025 	*timestamp = reg_ctrl << 16;
1026 
1027 	reg_id = priv->read(&mb->can_id);
1028 	if (reg_ctrl & FLEXCAN_MB_CNT_IDE)
1029 		cfd->can_id = ((reg_id >> 0) & CAN_EFF_MASK) | CAN_EFF_FLAG;
1030 	else
1031 		cfd->can_id = (reg_id >> 18) & CAN_SFF_MASK;
1032 
1033 	if (reg_ctrl & FLEXCAN_MB_CNT_EDL) {
1034 		cfd->len = can_fd_dlc2len((reg_ctrl >> 16) & 0xf);
1035 
1036 		if (reg_ctrl & FLEXCAN_MB_CNT_BRS)
1037 			cfd->flags |= CANFD_BRS;
1038 	} else {
1039 		cfd->len = can_cc_dlc2len((reg_ctrl >> 16) & 0xf);
1040 
1041 		if (reg_ctrl & FLEXCAN_MB_CNT_RTR)
1042 			cfd->can_id |= CAN_RTR_FLAG;
1043 	}
1044 
1045 	if (reg_ctrl & FLEXCAN_MB_CNT_ESI)
1046 		cfd->flags |= CANFD_ESI;
1047 
1048 	for (i = 0; i < cfd->len; i += sizeof(u32)) {
1049 		__be32 data = cpu_to_be32(priv->read(&mb->data[i / sizeof(u32)]));
1050 		*(__be32 *)(cfd->data + i) = data;
1051 	}
1052 
1053  mark_as_read:
1054 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX)
1055 		flexcan_write64(priv, FLEXCAN_IFLAG_MB(n), &regs->iflag1);
1056 	else
1057 		priv->write(FLEXCAN_IFLAG_RX_FIFO_AVAILABLE, &regs->iflag1);
1058 
1059 	/* Read the Free Running Timer. It is optional but recommended
1060 	 * to unlock Mailbox as soon as possible and make it available
1061 	 * for reception.
1062 	 */
1063 	priv->read(&regs->timer);
1064 
1065 	return skb;
1066 }
1067 
flexcan_irq(int irq,void * dev_id)1068 static irqreturn_t flexcan_irq(int irq, void *dev_id)
1069 {
1070 	struct net_device *dev = dev_id;
1071 	struct net_device_stats *stats = &dev->stats;
1072 	struct flexcan_priv *priv = netdev_priv(dev);
1073 	struct flexcan_regs __iomem *regs = priv->regs;
1074 	irqreturn_t handled = IRQ_NONE;
1075 	u64 reg_iflag_tx;
1076 	u32 reg_esr;
1077 	enum can_state last_state = priv->can.state;
1078 
1079 	/* reception interrupt */
1080 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX) {
1081 		u64 reg_iflag_rx;
1082 		int ret;
1083 
1084 		while ((reg_iflag_rx = flexcan_read_reg_iflag_rx(priv))) {
1085 			handled = IRQ_HANDLED;
1086 			ret = can_rx_offload_irq_offload_timestamp(&priv->offload,
1087 								   reg_iflag_rx);
1088 			if (!ret)
1089 				break;
1090 		}
1091 	} else {
1092 		u32 reg_iflag1;
1093 
1094 		reg_iflag1 = priv->read(&regs->iflag1);
1095 		if (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE) {
1096 			handled = IRQ_HANDLED;
1097 			can_rx_offload_irq_offload_fifo(&priv->offload);
1098 		}
1099 
1100 		/* FIFO overflow interrupt */
1101 		if (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_OVERFLOW) {
1102 			handled = IRQ_HANDLED;
1103 			priv->write(FLEXCAN_IFLAG_RX_FIFO_OVERFLOW,
1104 				    &regs->iflag1);
1105 			dev->stats.rx_over_errors++;
1106 			dev->stats.rx_errors++;
1107 		}
1108 	}
1109 
1110 	reg_iflag_tx = flexcan_read_reg_iflag_tx(priv);
1111 
1112 	/* transmission complete interrupt */
1113 	if (reg_iflag_tx & priv->tx_mask) {
1114 		u32 reg_ctrl = priv->read(&priv->tx_mb->can_ctrl);
1115 
1116 		handled = IRQ_HANDLED;
1117 		stats->tx_bytes +=
1118 			can_rx_offload_get_echo_skb_queue_timestamp(&priv->offload, 0,
1119 								    reg_ctrl << 16, NULL);
1120 		stats->tx_packets++;
1121 
1122 		/* after sending a RTR frame MB is in RX mode */
1123 		priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
1124 			    &priv->tx_mb->can_ctrl);
1125 		flexcan_write64(priv, priv->tx_mask, &regs->iflag1);
1126 		netif_wake_queue(dev);
1127 	}
1128 
1129 	reg_esr = priv->read(&regs->esr);
1130 
1131 	/* ACK all bus error, state change and wake IRQ sources */
1132 	if (reg_esr & (FLEXCAN_ESR_ALL_INT | FLEXCAN_ESR_WAK_INT)) {
1133 		handled = IRQ_HANDLED;
1134 		priv->write(reg_esr & (FLEXCAN_ESR_ALL_INT | FLEXCAN_ESR_WAK_INT), &regs->esr);
1135 	}
1136 
1137 	/* state change interrupt or broken error state quirk fix is enabled */
1138 	if ((reg_esr & FLEXCAN_ESR_ERR_STATE) ||
1139 	    (priv->devtype_data.quirks & (FLEXCAN_QUIRK_BROKEN_WERR_STATE |
1140 					   FLEXCAN_QUIRK_BROKEN_PERR_STATE)))
1141 		flexcan_irq_state(dev, reg_esr);
1142 
1143 	/* bus error IRQ - handle if bus error reporting is activated */
1144 	if ((reg_esr & FLEXCAN_ESR_ERR_BUS) &&
1145 	    (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
1146 		flexcan_irq_bus_err(dev, reg_esr);
1147 
1148 	/* availability of error interrupt among state transitions in case
1149 	 * bus error reporting is de-activated and
1150 	 * FLEXCAN_QUIRK_BROKEN_PERR_STATE is enabled:
1151 	 *  +--------------------------------------------------------------+
1152 	 *  | +----------------------------------------------+ [stopped /  |
1153 	 *  | |                                              |  sleeping] -+
1154 	 *  +-+-> active <-> warning <-> passive -> bus off -+
1155 	 *        ___________^^^^^^^^^^^^_______________________________
1156 	 *        disabled(1)  enabled             disabled
1157 	 *
1158 	 * (1): enabled if FLEXCAN_QUIRK_BROKEN_WERR_STATE is enabled
1159 	 */
1160 	if ((last_state != priv->can.state) &&
1161 	    (priv->devtype_data.quirks & FLEXCAN_QUIRK_BROKEN_PERR_STATE) &&
1162 	    !(priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)) {
1163 		switch (priv->can.state) {
1164 		case CAN_STATE_ERROR_ACTIVE:
1165 			if (priv->devtype_data.quirks &
1166 			    FLEXCAN_QUIRK_BROKEN_WERR_STATE)
1167 				flexcan_error_irq_enable(priv);
1168 			else
1169 				flexcan_error_irq_disable(priv);
1170 			break;
1171 
1172 		case CAN_STATE_ERROR_WARNING:
1173 			flexcan_error_irq_enable(priv);
1174 			break;
1175 
1176 		case CAN_STATE_ERROR_PASSIVE:
1177 		case CAN_STATE_BUS_OFF:
1178 			flexcan_error_irq_disable(priv);
1179 			break;
1180 
1181 		default:
1182 			break;
1183 		}
1184 	}
1185 
1186 	if (handled)
1187 		can_rx_offload_irq_finish(&priv->offload);
1188 
1189 	return handled;
1190 }
1191 
flexcan_set_bittiming_ctrl(const struct net_device * dev)1192 static void flexcan_set_bittiming_ctrl(const struct net_device *dev)
1193 {
1194 	const struct flexcan_priv *priv = netdev_priv(dev);
1195 	const struct can_bittiming *bt = &priv->can.bittiming;
1196 	struct flexcan_regs __iomem *regs = priv->regs;
1197 	u32 reg;
1198 
1199 	reg = priv->read(&regs->ctrl);
1200 	reg &= ~(FLEXCAN_CTRL_PRESDIV(0xff) |
1201 		 FLEXCAN_CTRL_RJW(0x3) |
1202 		 FLEXCAN_CTRL_PSEG1(0x7) |
1203 		 FLEXCAN_CTRL_PSEG2(0x7) |
1204 		 FLEXCAN_CTRL_PROPSEG(0x7));
1205 
1206 	reg |= FLEXCAN_CTRL_PRESDIV(bt->brp - 1) |
1207 		FLEXCAN_CTRL_PSEG1(bt->phase_seg1 - 1) |
1208 		FLEXCAN_CTRL_PSEG2(bt->phase_seg2 - 1) |
1209 		FLEXCAN_CTRL_RJW(bt->sjw - 1) |
1210 		FLEXCAN_CTRL_PROPSEG(bt->prop_seg - 1);
1211 
1212 	netdev_dbg(dev, "writing ctrl=0x%08x\n", reg);
1213 	priv->write(reg, &regs->ctrl);
1214 
1215 	/* print chip status */
1216 	netdev_dbg(dev, "%s: mcr=0x%08x ctrl=0x%08x\n", __func__,
1217 		   priv->read(&regs->mcr), priv->read(&regs->ctrl));
1218 }
1219 
flexcan_set_bittiming_cbt(const struct net_device * dev)1220 static void flexcan_set_bittiming_cbt(const struct net_device *dev)
1221 {
1222 	struct flexcan_priv *priv = netdev_priv(dev);
1223 	struct can_bittiming *bt = &priv->can.bittiming;
1224 	struct can_bittiming *dbt = &priv->can.data_bittiming;
1225 	struct flexcan_regs __iomem *regs = priv->regs;
1226 	u32 reg_cbt, reg_fdctrl;
1227 
1228 	/* CBT */
1229 	/* CBT[EPSEG1] is 5 bit long and CBT[EPROPSEG] is 6 bit
1230 	 * long. The can_calc_bittiming() tries to divide the tseg1
1231 	 * equally between phase_seg1 and prop_seg, which may not fit
1232 	 * in CBT register. Therefore, if phase_seg1 is more than
1233 	 * possible value, increase prop_seg and decrease phase_seg1.
1234 	 */
1235 	if (bt->phase_seg1 > 0x20) {
1236 		bt->prop_seg += (bt->phase_seg1 - 0x20);
1237 		bt->phase_seg1 = 0x20;
1238 	}
1239 
1240 	reg_cbt = FLEXCAN_CBT_BTF |
1241 		FIELD_PREP(FLEXCAN_CBT_EPRESDIV_MASK, bt->brp - 1) |
1242 		FIELD_PREP(FLEXCAN_CBT_ERJW_MASK, bt->sjw - 1) |
1243 		FIELD_PREP(FLEXCAN_CBT_EPROPSEG_MASK, bt->prop_seg - 1) |
1244 		FIELD_PREP(FLEXCAN_CBT_EPSEG1_MASK, bt->phase_seg1 - 1) |
1245 		FIELD_PREP(FLEXCAN_CBT_EPSEG2_MASK, bt->phase_seg2 - 1);
1246 
1247 	netdev_dbg(dev, "writing cbt=0x%08x\n", reg_cbt);
1248 	priv->write(reg_cbt, &regs->cbt);
1249 
1250 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
1251 		u32 reg_fdcbt, reg_ctrl2;
1252 
1253 		if (bt->brp != dbt->brp)
1254 			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",
1255 				    dbt->brp, bt->brp);
1256 
1257 		/* FDCBT */
1258 		/* FDCBT[FPSEG1] is 3 bit long and FDCBT[FPROPSEG] is
1259 		 * 5 bit long. The can_calc_bittiming tries to divide
1260 		 * the tseg1 equally between phase_seg1 and prop_seg,
1261 		 * which may not fit in FDCBT register. Therefore, if
1262 		 * phase_seg1 is more than possible value, increase
1263 		 * prop_seg and decrease phase_seg1
1264 		 */
1265 		if (dbt->phase_seg1 > 0x8) {
1266 			dbt->prop_seg += (dbt->phase_seg1 - 0x8);
1267 			dbt->phase_seg1 = 0x8;
1268 		}
1269 
1270 		reg_fdcbt = priv->read(&regs->fdcbt);
1271 		reg_fdcbt &= ~(FIELD_PREP(FLEXCAN_FDCBT_FPRESDIV_MASK, 0x3ff) |
1272 			       FIELD_PREP(FLEXCAN_FDCBT_FRJW_MASK, 0x7) |
1273 			       FIELD_PREP(FLEXCAN_FDCBT_FPROPSEG_MASK, 0x1f) |
1274 			       FIELD_PREP(FLEXCAN_FDCBT_FPSEG1_MASK, 0x7) |
1275 			       FIELD_PREP(FLEXCAN_FDCBT_FPSEG2_MASK, 0x7));
1276 
1277 		reg_fdcbt |= FIELD_PREP(FLEXCAN_FDCBT_FPRESDIV_MASK, dbt->brp - 1) |
1278 			FIELD_PREP(FLEXCAN_FDCBT_FRJW_MASK, dbt->sjw - 1) |
1279 			FIELD_PREP(FLEXCAN_FDCBT_FPROPSEG_MASK, dbt->prop_seg) |
1280 			FIELD_PREP(FLEXCAN_FDCBT_FPSEG1_MASK, dbt->phase_seg1 - 1) |
1281 			FIELD_PREP(FLEXCAN_FDCBT_FPSEG2_MASK, dbt->phase_seg2 - 1);
1282 
1283 		netdev_dbg(dev, "writing fdcbt=0x%08x\n", reg_fdcbt);
1284 		priv->write(reg_fdcbt, &regs->fdcbt);
1285 
1286 		/* CTRL2 */
1287 		reg_ctrl2 = priv->read(&regs->ctrl2);
1288 		reg_ctrl2 &= ~FLEXCAN_CTRL2_ISOCANFDEN;
1289 		if (!(priv->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO))
1290 			reg_ctrl2 |= FLEXCAN_CTRL2_ISOCANFDEN;
1291 
1292 		netdev_dbg(dev, "writing ctrl2=0x%08x\n", reg_ctrl2);
1293 		priv->write(reg_ctrl2, &regs->ctrl2);
1294 	}
1295 
1296 	/* FDCTRL */
1297 	reg_fdctrl = priv->read(&regs->fdctrl);
1298 	reg_fdctrl &= ~(FLEXCAN_FDCTRL_FDRATE |
1299 			FIELD_PREP(FLEXCAN_FDCTRL_TDCOFF, 0x1f));
1300 
1301 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
1302 		reg_fdctrl |= FLEXCAN_FDCTRL_FDRATE;
1303 
1304 		if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) {
1305 			/* TDC must be disabled for Loop Back mode */
1306 			reg_fdctrl &= ~FLEXCAN_FDCTRL_TDCEN;
1307 		} else {
1308 			reg_fdctrl |= FLEXCAN_FDCTRL_TDCEN |
1309 				FIELD_PREP(FLEXCAN_FDCTRL_TDCOFF,
1310 					   ((dbt->phase_seg1 - 1) +
1311 					    dbt->prop_seg + 2) *
1312 					   ((dbt->brp - 1 ) + 1));
1313 		}
1314 	}
1315 
1316 	netdev_dbg(dev, "writing fdctrl=0x%08x\n", reg_fdctrl);
1317 	priv->write(reg_fdctrl, &regs->fdctrl);
1318 
1319 	netdev_dbg(dev, "%s: mcr=0x%08x ctrl=0x%08x ctrl2=0x%08x fdctrl=0x%08x cbt=0x%08x fdcbt=0x%08x\n",
1320 		   __func__,
1321 		   priv->read(&regs->mcr), priv->read(&regs->ctrl),
1322 		   priv->read(&regs->ctrl2), priv->read(&regs->fdctrl),
1323 		   priv->read(&regs->cbt), priv->read(&regs->fdcbt));
1324 }
1325 
flexcan_set_bittiming(struct net_device * dev)1326 static void flexcan_set_bittiming(struct net_device *dev)
1327 {
1328 	const struct flexcan_priv *priv = netdev_priv(dev);
1329 	struct flexcan_regs __iomem *regs = priv->regs;
1330 	u32 reg;
1331 
1332 	reg = priv->read(&regs->ctrl);
1333 	reg &= ~(FLEXCAN_CTRL_LPB | FLEXCAN_CTRL_SMP |
1334 		 FLEXCAN_CTRL_LOM);
1335 
1336 	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
1337 		reg |= FLEXCAN_CTRL_LPB;
1338 	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
1339 		reg |= FLEXCAN_CTRL_LOM;
1340 	if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
1341 		reg |= FLEXCAN_CTRL_SMP;
1342 
1343 	netdev_dbg(dev, "writing ctrl=0x%08x\n", reg);
1344 	priv->write(reg, &regs->ctrl);
1345 
1346 	if (priv->can.ctrlmode_supported & CAN_CTRLMODE_FD)
1347 		return flexcan_set_bittiming_cbt(dev);
1348 	else
1349 		return flexcan_set_bittiming_ctrl(dev);
1350 }
1351 
flexcan_ram_init(struct net_device * dev)1352 static void flexcan_ram_init(struct net_device *dev)
1353 {
1354 	struct flexcan_priv *priv = netdev_priv(dev);
1355 	struct flexcan_regs __iomem *regs = priv->regs;
1356 	u32 reg_ctrl2;
1357 
1358 	/* 11.8.3.13 Detection and correction of memory errors:
1359 	 * CTRL2[WRMFRZ] grants write access to all memory positions
1360 	 * that require initialization, ranging from 0x080 to 0xADF
1361 	 * and from 0xF28 to 0xFFF when the CAN FD feature is enabled.
1362 	 * The RXMGMASK, RX14MASK, RX15MASK, and RXFGMASK registers
1363 	 * need to be initialized as well. MCR[RFEN] must not be set
1364 	 * during memory initialization.
1365 	 */
1366 	reg_ctrl2 = priv->read(&regs->ctrl2);
1367 	reg_ctrl2 |= FLEXCAN_CTRL2_WRMFRZ;
1368 	priv->write(reg_ctrl2, &regs->ctrl2);
1369 
1370 	memset_io(&regs->init, 0, sizeof(regs->init));
1371 
1372 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
1373 		memset_io(&regs->init_fd, 0, sizeof(regs->init_fd));
1374 
1375 	reg_ctrl2 &= ~FLEXCAN_CTRL2_WRMFRZ;
1376 	priv->write(reg_ctrl2, &regs->ctrl2);
1377 }
1378 
flexcan_rx_offload_setup(struct net_device * dev)1379 static int flexcan_rx_offload_setup(struct net_device *dev)
1380 {
1381 	struct flexcan_priv *priv = netdev_priv(dev);
1382 	int err;
1383 
1384 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
1385 		priv->mb_size = sizeof(struct flexcan_mb) + CANFD_MAX_DLEN;
1386 	else
1387 		priv->mb_size = sizeof(struct flexcan_mb) + CAN_MAX_DLEN;
1388 
1389 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_NR_MB_16)
1390 		priv->mb_count = 16;
1391 	else
1392 		priv->mb_count = (sizeof(priv->regs->mb[0]) / priv->mb_size) +
1393 				 (sizeof(priv->regs->mb[1]) / priv->mb_size);
1394 
1395 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX)
1396 		priv->tx_mb_reserved =
1397 			flexcan_get_mb(priv, FLEXCAN_TX_MB_RESERVED_RX_MAILBOX);
1398 	else
1399 		priv->tx_mb_reserved =
1400 			flexcan_get_mb(priv, FLEXCAN_TX_MB_RESERVED_RX_FIFO);
1401 	priv->tx_mb_idx = priv->mb_count - 1;
1402 	priv->tx_mb = flexcan_get_mb(priv, priv->tx_mb_idx);
1403 	priv->tx_mask = FLEXCAN_IFLAG_MB(priv->tx_mb_idx);
1404 
1405 	priv->offload.mailbox_read = flexcan_mailbox_read;
1406 
1407 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX) {
1408 		priv->offload.mb_first = FLEXCAN_RX_MB_RX_MAILBOX_FIRST;
1409 		priv->offload.mb_last = priv->mb_count - 2;
1410 
1411 		priv->rx_mask = GENMASK_ULL(priv->offload.mb_last,
1412 					    priv->offload.mb_first);
1413 		err = can_rx_offload_add_timestamp(dev, &priv->offload);
1414 	} else {
1415 		priv->rx_mask = FLEXCAN_IFLAG_RX_FIFO_OVERFLOW |
1416 			FLEXCAN_IFLAG_RX_FIFO_AVAILABLE;
1417 		err = can_rx_offload_add_fifo(dev, &priv->offload,
1418 					      FLEXCAN_NAPI_WEIGHT);
1419 	}
1420 
1421 	return err;
1422 }
1423 
flexcan_chip_interrupts_enable(const struct net_device * dev)1424 static void flexcan_chip_interrupts_enable(const struct net_device *dev)
1425 {
1426 	const struct flexcan_priv *priv = netdev_priv(dev);
1427 	struct flexcan_regs __iomem *regs = priv->regs;
1428 	u64 reg_imask;
1429 
1430 	disable_irq(dev->irq);
1431 	priv->write(priv->reg_ctrl_default, &regs->ctrl);
1432 	reg_imask = priv->rx_mask | priv->tx_mask;
1433 	priv->write(upper_32_bits(reg_imask), &regs->imask2);
1434 	priv->write(lower_32_bits(reg_imask), &regs->imask1);
1435 	enable_irq(dev->irq);
1436 }
1437 
flexcan_chip_interrupts_disable(const struct net_device * dev)1438 static void flexcan_chip_interrupts_disable(const struct net_device *dev)
1439 {
1440 	const struct flexcan_priv *priv = netdev_priv(dev);
1441 	struct flexcan_regs __iomem *regs = priv->regs;
1442 
1443 	priv->write(0, &regs->imask2);
1444 	priv->write(0, &regs->imask1);
1445 	priv->write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL,
1446 		    &regs->ctrl);
1447 }
1448 
1449 /* flexcan_chip_start
1450  *
1451  * this functions is entered with clocks enabled
1452  *
1453  */
flexcan_chip_start(struct net_device * dev)1454 static int flexcan_chip_start(struct net_device *dev)
1455 {
1456 	struct flexcan_priv *priv = netdev_priv(dev);
1457 	struct flexcan_regs __iomem *regs = priv->regs;
1458 	u32 reg_mcr, reg_ctrl, reg_ctrl2, reg_mecr;
1459 	int err, i;
1460 	struct flexcan_mb __iomem *mb;
1461 
1462 	/* enable module */
1463 	err = flexcan_chip_enable(priv);
1464 	if (err)
1465 		return err;
1466 
1467 	/* soft reset */
1468 	err = flexcan_chip_softreset(priv);
1469 	if (err)
1470 		goto out_chip_disable;
1471 
1472 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SUPPORT_ECC)
1473 		flexcan_ram_init(dev);
1474 
1475 	flexcan_set_bittiming(dev);
1476 
1477 	/* set freeze, halt */
1478 	err = flexcan_chip_freeze(priv);
1479 	if (err)
1480 		goto out_chip_disable;
1481 
1482 	/* MCR
1483 	 *
1484 	 * only supervisor access
1485 	 * enable warning int
1486 	 * enable individual RX masking
1487 	 * choose format C
1488 	 * set max mailbox number
1489 	 */
1490 	reg_mcr = priv->read(&regs->mcr);
1491 	reg_mcr &= ~FLEXCAN_MCR_MAXMB(0xff);
1492 	reg_mcr |= FLEXCAN_MCR_SUPV | FLEXCAN_MCR_WRN_EN | FLEXCAN_MCR_IRMQ |
1493 		FLEXCAN_MCR_IDAM_C | FLEXCAN_MCR_MAXMB(priv->tx_mb_idx);
1494 
1495 	/* MCR
1496 	 *
1497 	 * FIFO:
1498 	 * - disable for mailbox mode
1499 	 * - enable for FIFO mode
1500 	 */
1501 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX)
1502 		reg_mcr &= ~FLEXCAN_MCR_FEN;
1503 	else
1504 		reg_mcr |= FLEXCAN_MCR_FEN;
1505 
1506 	/* MCR
1507 	 *
1508 	 * NOTE: In loopback mode, the CAN_MCR[SRXDIS] cannot be
1509 	 *       asserted because this will impede the self reception
1510 	 *       of a transmitted message. This is not documented in
1511 	 *       earlier versions of flexcan block guide.
1512 	 *
1513 	 * Self Reception:
1514 	 * - enable Self Reception for loopback mode
1515 	 *   (by clearing "Self Reception Disable" bit)
1516 	 * - disable for normal operation
1517 	 */
1518 	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
1519 		reg_mcr &= ~FLEXCAN_MCR_SRX_DIS;
1520 	else
1521 		reg_mcr |= FLEXCAN_MCR_SRX_DIS;
1522 
1523 	/* MCR - CAN-FD */
1524 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
1525 		reg_mcr |= FLEXCAN_MCR_FDEN;
1526 	else
1527 		reg_mcr &= ~FLEXCAN_MCR_FDEN;
1528 
1529 	netdev_dbg(dev, "%s: writing mcr=0x%08x", __func__, reg_mcr);
1530 	priv->write(reg_mcr, &regs->mcr);
1531 
1532 	/* CTRL
1533 	 *
1534 	 * disable timer sync feature
1535 	 *
1536 	 * disable auto busoff recovery
1537 	 * transmit lowest buffer first
1538 	 *
1539 	 * enable tx and rx warning interrupt
1540 	 * enable bus off interrupt
1541 	 * (== FLEXCAN_CTRL_ERR_STATE)
1542 	 */
1543 	reg_ctrl = priv->read(&regs->ctrl);
1544 	reg_ctrl &= ~FLEXCAN_CTRL_TSYN;
1545 	reg_ctrl |= FLEXCAN_CTRL_BOFF_REC | FLEXCAN_CTRL_LBUF |
1546 		FLEXCAN_CTRL_ERR_STATE;
1547 
1548 	/* enable the "error interrupt" (FLEXCAN_CTRL_ERR_MSK),
1549 	 * on most Flexcan cores, too. Otherwise we don't get
1550 	 * any error warning or passive interrupts.
1551 	 */
1552 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_BROKEN_WERR_STATE ||
1553 	    priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
1554 		reg_ctrl |= FLEXCAN_CTRL_ERR_MSK;
1555 	else
1556 		reg_ctrl &= ~FLEXCAN_CTRL_ERR_MSK;
1557 
1558 	/* save for later use */
1559 	priv->reg_ctrl_default = reg_ctrl;
1560 	/* leave interrupts disabled for now */
1561 	reg_ctrl &= ~FLEXCAN_CTRL_ERR_ALL;
1562 	netdev_dbg(dev, "%s: writing ctrl=0x%08x", __func__, reg_ctrl);
1563 	priv->write(reg_ctrl, &regs->ctrl);
1564 
1565 	if ((priv->devtype_data.quirks & FLEXCAN_QUIRK_ENABLE_EACEN_RRS)) {
1566 		reg_ctrl2 = priv->read(&regs->ctrl2);
1567 		reg_ctrl2 |= FLEXCAN_CTRL2_EACEN | FLEXCAN_CTRL2_RRS;
1568 		priv->write(reg_ctrl2, &regs->ctrl2);
1569 	}
1570 
1571 	if (priv->can.ctrlmode_supported & CAN_CTRLMODE_FD) {
1572 		u32 reg_fdctrl;
1573 
1574 		reg_fdctrl = priv->read(&regs->fdctrl);
1575 		reg_fdctrl &= ~(FIELD_PREP(FLEXCAN_FDCTRL_MBDSR1, 0x3) |
1576 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR0, 0x3));
1577 
1578 		if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
1579 			reg_fdctrl |=
1580 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR1,
1581 					   FLEXCAN_FDCTRL_MBDSR_64) |
1582 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR0,
1583 					   FLEXCAN_FDCTRL_MBDSR_64);
1584 		} else {
1585 			reg_fdctrl |=
1586 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR1,
1587 					   FLEXCAN_FDCTRL_MBDSR_8) |
1588 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR0,
1589 					   FLEXCAN_FDCTRL_MBDSR_8);
1590 		}
1591 
1592 		netdev_dbg(dev, "%s: writing fdctrl=0x%08x",
1593 			   __func__, reg_fdctrl);
1594 		priv->write(reg_fdctrl, &regs->fdctrl);
1595 	}
1596 
1597 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX) {
1598 		for (i = priv->offload.mb_first; i <= priv->offload.mb_last; i++) {
1599 			mb = flexcan_get_mb(priv, i);
1600 			priv->write(FLEXCAN_MB_CODE_RX_EMPTY,
1601 				    &mb->can_ctrl);
1602 		}
1603 	} else {
1604 		/* clear and invalidate unused mailboxes first */
1605 		for (i = FLEXCAN_TX_MB_RESERVED_RX_FIFO; i < priv->mb_count; i++) {
1606 			mb = flexcan_get_mb(priv, i);
1607 			priv->write(FLEXCAN_MB_CODE_RX_INACTIVE,
1608 				    &mb->can_ctrl);
1609 		}
1610 	}
1611 
1612 	/* Errata ERR005829: mark first TX mailbox as INACTIVE */
1613 	priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
1614 		    &priv->tx_mb_reserved->can_ctrl);
1615 
1616 	/* mark TX mailbox as INACTIVE */
1617 	priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
1618 		    &priv->tx_mb->can_ctrl);
1619 
1620 	/* acceptance mask/acceptance code (accept everything) */
1621 	priv->write(0x0, &regs->rxgmask);
1622 	priv->write(0x0, &regs->rx14mask);
1623 	priv->write(0x0, &regs->rx15mask);
1624 
1625 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_DISABLE_RXFG)
1626 		priv->write(0x0, &regs->rxfgmask);
1627 
1628 	/* clear acceptance filters */
1629 	for (i = 0; i < priv->mb_count; i++)
1630 		priv->write(0, &regs->rximr[i]);
1631 
1632 	/* On Vybrid, disable non-correctable errors interrupt and
1633 	 * freeze mode. It still can correct the correctable errors
1634 	 * when HW supports ECC.
1635 	 *
1636 	 * This also works around errata e5295 which generates false
1637 	 * positive memory errors and put the device in freeze mode.
1638 	 */
1639 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_DISABLE_MECR) {
1640 		/* Follow the protocol as described in "Detection
1641 		 * and Correction of Memory Errors" to write to
1642 		 * MECR register (step 1 - 5)
1643 		 *
1644 		 * 1. By default, CTRL2[ECRWRE] = 0, MECR[ECRWRDIS] = 1
1645 		 * 2. set CTRL2[ECRWRE]
1646 		 */
1647 		reg_ctrl2 = priv->read(&regs->ctrl2);
1648 		reg_ctrl2 |= FLEXCAN_CTRL2_ECRWRE;
1649 		priv->write(reg_ctrl2, &regs->ctrl2);
1650 
1651 		/* 3. clear MECR[ECRWRDIS] */
1652 		reg_mecr = priv->read(&regs->mecr);
1653 		reg_mecr &= ~FLEXCAN_MECR_ECRWRDIS;
1654 		priv->write(reg_mecr, &regs->mecr);
1655 
1656 		/* 4. all writes to MECR must keep MECR[ECRWRDIS] cleared */
1657 		reg_mecr &= ~(FLEXCAN_MECR_NCEFAFRZ | FLEXCAN_MECR_HANCEI_MSK |
1658 			      FLEXCAN_MECR_FANCEI_MSK);
1659 		priv->write(reg_mecr, &regs->mecr);
1660 
1661 		/* 5. after configuration done, lock MECR by either
1662 		 * setting MECR[ECRWRDIS] or clearing CTRL2[ECRWRE]
1663 		 */
1664 		reg_mecr |= FLEXCAN_MECR_ECRWRDIS;
1665 		priv->write(reg_mecr, &regs->mecr);
1666 
1667 		reg_ctrl2 &= ~FLEXCAN_CTRL2_ECRWRE;
1668 		priv->write(reg_ctrl2, &regs->ctrl2);
1669 	}
1670 
1671 	/* synchronize with the can bus */
1672 	err = flexcan_chip_unfreeze(priv);
1673 	if (err)
1674 		goto out_chip_disable;
1675 
1676 	priv->can.state = CAN_STATE_ERROR_ACTIVE;
1677 
1678 	/* print chip status */
1679 	netdev_dbg(dev, "%s: reading mcr=0x%08x ctrl=0x%08x\n", __func__,
1680 		   priv->read(&regs->mcr), priv->read(&regs->ctrl));
1681 
1682 	return 0;
1683 
1684  out_chip_disable:
1685 	flexcan_chip_disable(priv);
1686 	return err;
1687 }
1688 
1689 /* __flexcan_chip_stop
1690  *
1691  * this function is entered with clocks enabled
1692  */
__flexcan_chip_stop(struct net_device * dev,bool disable_on_error)1693 static int __flexcan_chip_stop(struct net_device *dev, bool disable_on_error)
1694 {
1695 	struct flexcan_priv *priv = netdev_priv(dev);
1696 	int err;
1697 
1698 	/* freeze + disable module */
1699 	err = flexcan_chip_freeze(priv);
1700 	if (err && !disable_on_error)
1701 		return err;
1702 	err = flexcan_chip_disable(priv);
1703 	if (err && !disable_on_error)
1704 		goto out_chip_unfreeze;
1705 
1706 	priv->can.state = CAN_STATE_STOPPED;
1707 
1708 	return 0;
1709 
1710  out_chip_unfreeze:
1711 	flexcan_chip_unfreeze(priv);
1712 
1713 	return err;
1714 }
1715 
flexcan_chip_stop_disable_on_error(struct net_device * dev)1716 static inline int flexcan_chip_stop_disable_on_error(struct net_device *dev)
1717 {
1718 	return __flexcan_chip_stop(dev, true);
1719 }
1720 
flexcan_chip_stop(struct net_device * dev)1721 static inline int flexcan_chip_stop(struct net_device *dev)
1722 {
1723 	return __flexcan_chip_stop(dev, false);
1724 }
1725 
flexcan_open(struct net_device * dev)1726 static int flexcan_open(struct net_device *dev)
1727 {
1728 	struct flexcan_priv *priv = netdev_priv(dev);
1729 	int err;
1730 
1731 	if ((priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) &&
1732 	    (priv->can.ctrlmode & CAN_CTRLMODE_FD)) {
1733 		netdev_err(dev, "Three Samples mode and CAN-FD mode can't be used together\n");
1734 		return -EINVAL;
1735 	}
1736 
1737 	err = pm_runtime_resume_and_get(priv->dev);
1738 	if (err < 0)
1739 		return err;
1740 
1741 	err = open_candev(dev);
1742 	if (err)
1743 		goto out_runtime_put;
1744 
1745 	err = flexcan_transceiver_enable(priv);
1746 	if (err)
1747 		goto out_close;
1748 
1749 	err = flexcan_rx_offload_setup(dev);
1750 	if (err)
1751 		goto out_transceiver_disable;
1752 
1753 	err = flexcan_chip_start(dev);
1754 	if (err)
1755 		goto out_can_rx_offload_del;
1756 
1757 	can_rx_offload_enable(&priv->offload);
1758 
1759 	err = request_irq(dev->irq, flexcan_irq, IRQF_SHARED, dev->name, dev);
1760 	if (err)
1761 		goto out_can_rx_offload_disable;
1762 
1763 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_NR_IRQ_3) {
1764 		err = request_irq(priv->irq_boff,
1765 				  flexcan_irq, IRQF_SHARED, dev->name, dev);
1766 		if (err)
1767 			goto out_free_irq;
1768 
1769 		err = request_irq(priv->irq_err,
1770 				  flexcan_irq, IRQF_SHARED, dev->name, dev);
1771 		if (err)
1772 			goto out_free_irq_boff;
1773 	}
1774 
1775 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SECONDARY_MB_IRQ) {
1776 		err = request_irq(priv->irq_secondary_mb,
1777 				  flexcan_irq, IRQF_SHARED, dev->name, dev);
1778 		if (err)
1779 			goto out_free_irq_err;
1780 	}
1781 
1782 	flexcan_chip_interrupts_enable(dev);
1783 
1784 	netif_start_queue(dev);
1785 
1786 	return 0;
1787 
1788  out_free_irq_err:
1789 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_NR_IRQ_3)
1790 		free_irq(priv->irq_err, dev);
1791  out_free_irq_boff:
1792 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_NR_IRQ_3)
1793 		free_irq(priv->irq_boff, dev);
1794  out_free_irq:
1795 	free_irq(dev->irq, dev);
1796  out_can_rx_offload_disable:
1797 	can_rx_offload_disable(&priv->offload);
1798 	flexcan_chip_stop(dev);
1799  out_can_rx_offload_del:
1800 	can_rx_offload_del(&priv->offload);
1801  out_transceiver_disable:
1802 	flexcan_transceiver_disable(priv);
1803  out_close:
1804 	close_candev(dev);
1805  out_runtime_put:
1806 	pm_runtime_put(priv->dev);
1807 
1808 	return err;
1809 }
1810 
flexcan_close(struct net_device * dev)1811 static int flexcan_close(struct net_device *dev)
1812 {
1813 	struct flexcan_priv *priv = netdev_priv(dev);
1814 
1815 	netif_stop_queue(dev);
1816 	flexcan_chip_interrupts_disable(dev);
1817 
1818 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SECONDARY_MB_IRQ)
1819 		free_irq(priv->irq_secondary_mb, dev);
1820 
1821 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_NR_IRQ_3) {
1822 		free_irq(priv->irq_err, dev);
1823 		free_irq(priv->irq_boff, dev);
1824 	}
1825 
1826 	free_irq(dev->irq, dev);
1827 	can_rx_offload_disable(&priv->offload);
1828 	flexcan_chip_stop_disable_on_error(dev);
1829 
1830 	can_rx_offload_del(&priv->offload);
1831 	flexcan_transceiver_disable(priv);
1832 	close_candev(dev);
1833 
1834 	pm_runtime_put(priv->dev);
1835 
1836 	return 0;
1837 }
1838 
flexcan_set_mode(struct net_device * dev,enum can_mode mode)1839 static int flexcan_set_mode(struct net_device *dev, enum can_mode mode)
1840 {
1841 	int err;
1842 
1843 	switch (mode) {
1844 	case CAN_MODE_START:
1845 		err = flexcan_chip_start(dev);
1846 		if (err)
1847 			return err;
1848 
1849 		flexcan_chip_interrupts_enable(dev);
1850 
1851 		netif_wake_queue(dev);
1852 		break;
1853 
1854 	default:
1855 		return -EOPNOTSUPP;
1856 	}
1857 
1858 	return 0;
1859 }
1860 
1861 static const struct net_device_ops flexcan_netdev_ops = {
1862 	.ndo_open	= flexcan_open,
1863 	.ndo_stop	= flexcan_close,
1864 	.ndo_start_xmit	= flexcan_start_xmit,
1865 	.ndo_change_mtu = can_change_mtu,
1866 };
1867 
register_flexcandev(struct net_device * dev)1868 static int register_flexcandev(struct net_device *dev)
1869 {
1870 	struct flexcan_priv *priv = netdev_priv(dev);
1871 	struct flexcan_regs __iomem *regs = priv->regs;
1872 	u32 reg, err;
1873 
1874 	err = flexcan_clks_enable(priv);
1875 	if (err)
1876 		return err;
1877 
1878 	/* select "bus clock", chip must be disabled */
1879 	err = flexcan_chip_disable(priv);
1880 	if (err)
1881 		goto out_clks_disable;
1882 
1883 	reg = priv->read(&regs->ctrl);
1884 	if (priv->clk_src)
1885 		reg |= FLEXCAN_CTRL_CLK_SRC;
1886 	else
1887 		reg &= ~FLEXCAN_CTRL_CLK_SRC;
1888 	priv->write(reg, &regs->ctrl);
1889 
1890 	err = flexcan_chip_enable(priv);
1891 	if (err)
1892 		goto out_chip_disable;
1893 
1894 	/* set freeze, halt */
1895 	err = flexcan_chip_freeze(priv);
1896 	if (err)
1897 		goto out_chip_disable;
1898 
1899 	/* activate FIFO, restrict register access */
1900 	reg = priv->read(&regs->mcr);
1901 	reg |=  FLEXCAN_MCR_FEN | FLEXCAN_MCR_SUPV;
1902 	priv->write(reg, &regs->mcr);
1903 
1904 	/* Currently we only support newer versions of this core
1905 	 * featuring a RX hardware FIFO (although this driver doesn't
1906 	 * make use of it on some cores). Older cores, found on some
1907 	 * Coldfire derivates are not tested.
1908 	 */
1909 	reg = priv->read(&regs->mcr);
1910 	if (!(reg & FLEXCAN_MCR_FEN)) {
1911 		netdev_err(dev, "Could not enable RX FIFO, unsupported core\n");
1912 		err = -ENODEV;
1913 		goto out_chip_disable;
1914 	}
1915 
1916 	err = register_candev(dev);
1917 	if (err)
1918 		goto out_chip_disable;
1919 
1920 	/* Disable core and let pm_runtime_put() disable the clocks.
1921 	 * If CONFIG_PM is not enabled, the clocks will stay powered.
1922 	 */
1923 	flexcan_chip_disable(priv);
1924 	pm_runtime_put(priv->dev);
1925 
1926 	return 0;
1927 
1928  out_chip_disable:
1929 	flexcan_chip_disable(priv);
1930  out_clks_disable:
1931 	flexcan_clks_disable(priv);
1932 	return err;
1933 }
1934 
unregister_flexcandev(struct net_device * dev)1935 static void unregister_flexcandev(struct net_device *dev)
1936 {
1937 	unregister_candev(dev);
1938 }
1939 
flexcan_setup_stop_mode_gpr(struct platform_device * pdev)1940 static int flexcan_setup_stop_mode_gpr(struct platform_device *pdev)
1941 {
1942 	struct net_device *dev = platform_get_drvdata(pdev);
1943 	struct device_node *np = pdev->dev.of_node;
1944 	struct device_node *gpr_np;
1945 	struct flexcan_priv *priv;
1946 	phandle phandle;
1947 	u32 out_val[3];
1948 	int ret;
1949 
1950 	if (!np)
1951 		return -EINVAL;
1952 
1953 	/* stop mode property format is:
1954 	 * <&gpr req_gpr req_bit>.
1955 	 */
1956 	ret = of_property_read_u32_array(np, "fsl,stop-mode", out_val,
1957 					 ARRAY_SIZE(out_val));
1958 	if (ret) {
1959 		dev_dbg(&pdev->dev, "no stop-mode property\n");
1960 		return ret;
1961 	}
1962 	phandle = *out_val;
1963 
1964 	gpr_np = of_find_node_by_phandle(phandle);
1965 	if (!gpr_np) {
1966 		dev_dbg(&pdev->dev, "could not find gpr node by phandle\n");
1967 		return -ENODEV;
1968 	}
1969 
1970 	priv = netdev_priv(dev);
1971 	priv->stm.gpr = syscon_node_to_regmap(gpr_np);
1972 	if (IS_ERR(priv->stm.gpr)) {
1973 		dev_dbg(&pdev->dev, "could not find gpr regmap\n");
1974 		ret = PTR_ERR(priv->stm.gpr);
1975 		goto out_put_node;
1976 	}
1977 
1978 	priv->stm.req_gpr = out_val[1];
1979 	priv->stm.req_bit = out_val[2];
1980 
1981 	dev_dbg(&pdev->dev,
1982 		"gpr %s req_gpr=0x02%x req_bit=%u\n",
1983 		gpr_np->full_name, priv->stm.req_gpr, priv->stm.req_bit);
1984 
1985 	return 0;
1986 
1987 out_put_node:
1988 	of_node_put(gpr_np);
1989 	return ret;
1990 }
1991 
flexcan_setup_stop_mode_scfw(struct platform_device * pdev)1992 static int flexcan_setup_stop_mode_scfw(struct platform_device *pdev)
1993 {
1994 	struct net_device *dev = platform_get_drvdata(pdev);
1995 	struct flexcan_priv *priv;
1996 	u8 scu_idx;
1997 	int ret;
1998 
1999 	ret = of_property_read_u8(pdev->dev.of_node, "fsl,scu-index", &scu_idx);
2000 	if (ret < 0) {
2001 		dev_dbg(&pdev->dev, "failed to get scu index\n");
2002 		return ret;
2003 	}
2004 
2005 	priv = netdev_priv(dev);
2006 	priv->scu_idx = scu_idx;
2007 
2008 	/* this function could be deferred probe, return -EPROBE_DEFER */
2009 	return imx_scu_get_handle(&priv->sc_ipc_handle);
2010 }
2011 
2012 /* flexcan_setup_stop_mode - Setup stop mode for wakeup
2013  *
2014  * Return: = 0 setup stop mode successfully or doesn't support this feature
2015  *         < 0 fail to setup stop mode (could be deferred probe)
2016  */
flexcan_setup_stop_mode(struct platform_device * pdev)2017 static int flexcan_setup_stop_mode(struct platform_device *pdev)
2018 {
2019 	struct net_device *dev = platform_get_drvdata(pdev);
2020 	struct flexcan_priv *priv;
2021 	int ret;
2022 
2023 	priv = netdev_priv(dev);
2024 
2025 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW)
2026 		ret = flexcan_setup_stop_mode_scfw(pdev);
2027 	else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR)
2028 		ret = flexcan_setup_stop_mode_gpr(pdev);
2029 	else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI)
2030 		/* ATF will handle all STOP_IPG related work */
2031 		ret = 0;
2032 	else
2033 		/* return 0 directly if doesn't support stop mode feature */
2034 		return 0;
2035 
2036 	/* If ret is -EINVAL, this means SoC claim to support stop mode, but
2037 	 * dts file lack the stop mode property definition. For this case,
2038 	 * directly return 0, this will skip the wakeup capable setting and
2039 	 * will not block the driver probe.
2040 	 */
2041 	if (ret == -EINVAL)
2042 		return 0;
2043 	else if (ret)
2044 		return ret;
2045 
2046 	device_set_wakeup_capable(&pdev->dev, true);
2047 
2048 	if (of_property_read_bool(pdev->dev.of_node, "wakeup-source"))
2049 		device_set_wakeup_enable(&pdev->dev, true);
2050 
2051 	return 0;
2052 }
2053 
2054 static const struct of_device_id flexcan_of_match[] = {
2055 	{ .compatible = "fsl,imx8qm-flexcan", .data = &fsl_imx8qm_devtype_data, },
2056 	{ .compatible = "fsl,imx8mp-flexcan", .data = &fsl_imx8mp_devtype_data, },
2057 	{ .compatible = "fsl,imx93-flexcan", .data = &fsl_imx93_devtype_data, },
2058 	{ .compatible = "fsl,imx95-flexcan", .data = &fsl_imx95_devtype_data, },
2059 	{ .compatible = "fsl,imx6q-flexcan", .data = &fsl_imx6q_devtype_data, },
2060 	{ .compatible = "fsl,imx28-flexcan", .data = &fsl_imx28_devtype_data, },
2061 	{ .compatible = "fsl,imx53-flexcan", .data = &fsl_imx25_devtype_data, },
2062 	{ .compatible = "fsl,imx35-flexcan", .data = &fsl_imx25_devtype_data, },
2063 	{ .compatible = "fsl,imx25-flexcan", .data = &fsl_imx25_devtype_data, },
2064 	{ .compatible = "fsl,p1010-flexcan", .data = &fsl_p1010_devtype_data, },
2065 	{ .compatible = "fsl,vf610-flexcan", .data = &fsl_vf610_devtype_data, },
2066 	{ .compatible = "fsl,ls1021ar2-flexcan", .data = &fsl_ls1021a_r2_devtype_data, },
2067 	{ .compatible = "fsl,lx2160ar1-flexcan", .data = &fsl_lx2160a_r1_devtype_data, },
2068 	{ .compatible = "nxp,s32g2-flexcan", .data = &nxp_s32g2_devtype_data, },
2069 	{ /* sentinel */ },
2070 };
2071 MODULE_DEVICE_TABLE(of, flexcan_of_match);
2072 
2073 static const struct platform_device_id flexcan_id_table[] = {
2074 	{
2075 		.name = "flexcan-mcf5441x",
2076 		.driver_data = (kernel_ulong_t)&fsl_mcf5441x_devtype_data,
2077 	}, {
2078 		/* sentinel */
2079 	},
2080 };
2081 MODULE_DEVICE_TABLE(platform, flexcan_id_table);
2082 
flexcan_probe(struct platform_device * pdev)2083 static int flexcan_probe(struct platform_device *pdev)
2084 {
2085 	const struct flexcan_devtype_data *devtype_data;
2086 	struct net_device *dev;
2087 	struct flexcan_priv *priv;
2088 	struct regulator *reg_xceiver;
2089 	struct clk *clk_ipg = NULL, *clk_per = NULL;
2090 	struct flexcan_regs __iomem *regs;
2091 	struct flexcan_platform_data *pdata;
2092 	int err, irq;
2093 	u8 clk_src = 1;
2094 	u32 clock_freq = 0;
2095 
2096 	reg_xceiver = devm_regulator_get_optional(&pdev->dev, "xceiver");
2097 	if (PTR_ERR(reg_xceiver) == -EPROBE_DEFER)
2098 		return -EPROBE_DEFER;
2099 	else if (PTR_ERR(reg_xceiver) == -ENODEV)
2100 		reg_xceiver = NULL;
2101 	else if (IS_ERR(reg_xceiver))
2102 		return PTR_ERR(reg_xceiver);
2103 
2104 	if (pdev->dev.of_node) {
2105 		of_property_read_u32(pdev->dev.of_node,
2106 				     "clock-frequency", &clock_freq);
2107 		of_property_read_u8(pdev->dev.of_node,
2108 				    "fsl,clk-source", &clk_src);
2109 	} else {
2110 		pdata = dev_get_platdata(&pdev->dev);
2111 		if (pdata) {
2112 			clock_freq = pdata->clock_frequency;
2113 			clk_src = pdata->clk_src;
2114 		}
2115 	}
2116 
2117 	if (!clock_freq) {
2118 		clk_ipg = devm_clk_get(&pdev->dev, "ipg");
2119 		if (IS_ERR(clk_ipg)) {
2120 			dev_err(&pdev->dev, "no ipg clock defined\n");
2121 			return PTR_ERR(clk_ipg);
2122 		}
2123 
2124 		clk_per = devm_clk_get(&pdev->dev, "per");
2125 		if (IS_ERR(clk_per)) {
2126 			dev_err(&pdev->dev, "no per clock defined\n");
2127 			return PTR_ERR(clk_per);
2128 		}
2129 		clock_freq = clk_get_rate(clk_per);
2130 	}
2131 
2132 	irq = platform_get_irq(pdev, 0);
2133 	if (irq < 0)
2134 		return irq;
2135 
2136 	regs = devm_platform_ioremap_resource(pdev, 0);
2137 	if (IS_ERR(regs))
2138 		return PTR_ERR(regs);
2139 
2140 	devtype_data = device_get_match_data(&pdev->dev);
2141 
2142 	if ((devtype_data->quirks & FLEXCAN_QUIRK_SUPPORT_FD) &&
2143 	    !((devtype_data->quirks &
2144 	       (FLEXCAN_QUIRK_USE_RX_MAILBOX |
2145 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
2146 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR |
2147 		FLEXCAN_QUIRK_SUPPORT_RX_FIFO)) ==
2148 	      (FLEXCAN_QUIRK_USE_RX_MAILBOX |
2149 	       FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
2150 	       FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR))) {
2151 		dev_err(&pdev->dev, "CAN-FD mode doesn't work in RX-FIFO mode!\n");
2152 		return -EINVAL;
2153 	}
2154 
2155 	if ((devtype_data->quirks &
2156 	     (FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
2157 	      FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR)) ==
2158 	    FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR) {
2159 		dev_err(&pdev->dev,
2160 			"Quirks (0x%08x) inconsistent: RX_MAILBOX_RX supported but not RX_MAILBOX\n",
2161 			devtype_data->quirks);
2162 		return -EINVAL;
2163 	}
2164 
2165 	dev = alloc_candev(sizeof(struct flexcan_priv), 1);
2166 	if (!dev)
2167 		return -ENOMEM;
2168 
2169 	platform_set_drvdata(pdev, dev);
2170 	SET_NETDEV_DEV(dev, &pdev->dev);
2171 
2172 	dev->netdev_ops = &flexcan_netdev_ops;
2173 	dev->ethtool_ops = &flexcan_ethtool_ops;
2174 	dev->irq = irq;
2175 	dev->flags |= IFF_ECHO;
2176 
2177 	priv = netdev_priv(dev);
2178 	priv->devtype_data = *devtype_data;
2179 
2180 	if (of_property_read_bool(pdev->dev.of_node, "big-endian") ||
2181 	    priv->devtype_data.quirks & FLEXCAN_QUIRK_DEFAULT_BIG_ENDIAN) {
2182 		priv->read = flexcan_read_be;
2183 		priv->write = flexcan_write_be;
2184 	} else {
2185 		priv->read = flexcan_read_le;
2186 		priv->write = flexcan_write_le;
2187 	}
2188 
2189 	priv->dev = &pdev->dev;
2190 	priv->can.clock.freq = clock_freq;
2191 	priv->can.do_set_mode = flexcan_set_mode;
2192 	priv->can.do_get_berr_counter = flexcan_get_berr_counter;
2193 	priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
2194 		CAN_CTRLMODE_LISTENONLY	| CAN_CTRLMODE_3_SAMPLES |
2195 		CAN_CTRLMODE_BERR_REPORTING;
2196 	priv->regs = regs;
2197 	priv->clk_ipg = clk_ipg;
2198 	priv->clk_per = clk_per;
2199 	priv->clk_src = clk_src;
2200 	priv->reg_xceiver = reg_xceiver;
2201 
2202 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_NR_IRQ_3) {
2203 		priv->irq_boff = platform_get_irq(pdev, 1);
2204 		if (priv->irq_boff < 0) {
2205 			err = priv->irq_boff;
2206 			goto failed_platform_get_irq;
2207 		}
2208 		priv->irq_err = platform_get_irq(pdev, 2);
2209 		if (priv->irq_err < 0) {
2210 			err = priv->irq_err;
2211 			goto failed_platform_get_irq;
2212 		}
2213 	}
2214 
2215 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SECONDARY_MB_IRQ) {
2216 		priv->irq_secondary_mb = platform_get_irq_byname(pdev, "mb-1");
2217 		if (priv->irq_secondary_mb < 0) {
2218 			err = priv->irq_secondary_mb;
2219 			goto failed_platform_get_irq;
2220 		}
2221 	}
2222 
2223 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SUPPORT_FD) {
2224 		priv->can.ctrlmode_supported |= CAN_CTRLMODE_FD |
2225 			CAN_CTRLMODE_FD_NON_ISO;
2226 		priv->can.bittiming_const = &flexcan_fd_bittiming_const;
2227 		priv->can.data_bittiming_const =
2228 			&flexcan_fd_data_bittiming_const;
2229 	} else {
2230 		priv->can.bittiming_const = &flexcan_bittiming_const;
2231 	}
2232 
2233 	pm_runtime_get_noresume(&pdev->dev);
2234 	pm_runtime_set_active(&pdev->dev);
2235 	pm_runtime_enable(&pdev->dev);
2236 
2237 	err = register_flexcandev(dev);
2238 	if (err) {
2239 		dev_err(&pdev->dev, "registering netdev failed\n");
2240 		goto failed_register;
2241 	}
2242 
2243 	err = flexcan_setup_stop_mode(pdev);
2244 	if (err < 0) {
2245 		dev_err_probe(&pdev->dev, err, "setup stop mode failed\n");
2246 		goto failed_setup_stop_mode;
2247 	}
2248 
2249 	of_can_transceiver(dev);
2250 
2251 	return 0;
2252 
2253  failed_setup_stop_mode:
2254 	unregister_flexcandev(dev);
2255  failed_register:
2256 	pm_runtime_put_noidle(&pdev->dev);
2257 	pm_runtime_disable(&pdev->dev);
2258  failed_platform_get_irq:
2259 	free_candev(dev);
2260 	return err;
2261 }
2262 
flexcan_remove(struct platform_device * pdev)2263 static void flexcan_remove(struct platform_device *pdev)
2264 {
2265 	struct net_device *dev = platform_get_drvdata(pdev);
2266 
2267 	device_set_wakeup_enable(&pdev->dev, false);
2268 	device_set_wakeup_capable(&pdev->dev, false);
2269 	unregister_flexcandev(dev);
2270 	pm_runtime_disable(&pdev->dev);
2271 	free_candev(dev);
2272 }
2273 
flexcan_suspend(struct device * device)2274 static int __maybe_unused flexcan_suspend(struct device *device)
2275 {
2276 	struct net_device *dev = dev_get_drvdata(device);
2277 	struct flexcan_priv *priv = netdev_priv(dev);
2278 	int err;
2279 
2280 	if (netif_running(dev)) {
2281 		/* if wakeup is enabled, enter stop mode
2282 		 * else enter disabled mode.
2283 		 */
2284 		if (device_may_wakeup(device)) {
2285 			enable_irq_wake(dev->irq);
2286 			err = flexcan_enter_stop_mode(priv);
2287 			if (err)
2288 				return err;
2289 		} else {
2290 			err = flexcan_chip_stop(dev);
2291 			if (err)
2292 				return err;
2293 
2294 			flexcan_chip_interrupts_disable(dev);
2295 
2296 			err = flexcan_transceiver_disable(priv);
2297 			if (err)
2298 				return err;
2299 
2300 			err = pinctrl_pm_select_sleep_state(device);
2301 			if (err)
2302 				return err;
2303 		}
2304 		netif_stop_queue(dev);
2305 		netif_device_detach(dev);
2306 
2307 		priv->can.state = CAN_STATE_SLEEPING;
2308 	}
2309 
2310 	return 0;
2311 }
2312 
flexcan_resume(struct device * device)2313 static int __maybe_unused flexcan_resume(struct device *device)
2314 {
2315 	struct net_device *dev = dev_get_drvdata(device);
2316 	struct flexcan_priv *priv = netdev_priv(dev);
2317 	int err;
2318 
2319 	if (netif_running(dev)) {
2320 		netif_device_attach(dev);
2321 		netif_start_queue(dev);
2322 		if (device_may_wakeup(device)) {
2323 			disable_irq_wake(dev->irq);
2324 			err = flexcan_exit_stop_mode(priv);
2325 			if (err)
2326 				return err;
2327 		} else {
2328 			err = pinctrl_pm_select_default_state(device);
2329 			if (err)
2330 				return err;
2331 
2332 			err = flexcan_transceiver_enable(priv);
2333 			if (err)
2334 				return err;
2335 
2336 			err = flexcan_chip_start(dev);
2337 			if (err) {
2338 				flexcan_transceiver_disable(priv);
2339 				return err;
2340 			}
2341 
2342 			flexcan_chip_interrupts_enable(dev);
2343 		}
2344 
2345 		priv->can.state = CAN_STATE_ERROR_ACTIVE;
2346 	}
2347 
2348 	return 0;
2349 }
2350 
flexcan_runtime_suspend(struct device * device)2351 static int __maybe_unused flexcan_runtime_suspend(struct device *device)
2352 {
2353 	struct net_device *dev = dev_get_drvdata(device);
2354 	struct flexcan_priv *priv = netdev_priv(dev);
2355 
2356 	flexcan_clks_disable(priv);
2357 
2358 	return 0;
2359 }
2360 
flexcan_runtime_resume(struct device * device)2361 static int __maybe_unused flexcan_runtime_resume(struct device *device)
2362 {
2363 	struct net_device *dev = dev_get_drvdata(device);
2364 	struct flexcan_priv *priv = netdev_priv(dev);
2365 
2366 	return flexcan_clks_enable(priv);
2367 }
2368 
flexcan_noirq_suspend(struct device * device)2369 static int __maybe_unused flexcan_noirq_suspend(struct device *device)
2370 {
2371 	struct net_device *dev = dev_get_drvdata(device);
2372 	struct flexcan_priv *priv = netdev_priv(dev);
2373 
2374 	if (netif_running(dev)) {
2375 		int err;
2376 
2377 		if (device_may_wakeup(device))
2378 			flexcan_enable_wakeup_irq(priv, true);
2379 
2380 		/* For FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI, it need ATF to send
2381 		 * to SM through SCMI protocol, SM will assert the IPG_STOP
2382 		 * signal. But all this works need the CAN clocks keep on.
2383 		 * After the CAN module get the IPG_STOP mode, and switch to
2384 		 * STOP mode, whether still keep the CAN clocks on or gate them
2385 		 * off depend on the Hardware design.
2386 		 */
2387 		if (!(device_may_wakeup(device) &&
2388 		      priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI)) {
2389 			err = pm_runtime_force_suspend(device);
2390 			if (err)
2391 				return err;
2392 		}
2393 	}
2394 
2395 	return 0;
2396 }
2397 
flexcan_noirq_resume(struct device * device)2398 static int __maybe_unused flexcan_noirq_resume(struct device *device)
2399 {
2400 	struct net_device *dev = dev_get_drvdata(device);
2401 	struct flexcan_priv *priv = netdev_priv(dev);
2402 
2403 	if (netif_running(dev)) {
2404 		int err;
2405 
2406 		if (!(device_may_wakeup(device) &&
2407 		      priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI)) {
2408 			err = pm_runtime_force_resume(device);
2409 			if (err)
2410 				return err;
2411 		}
2412 
2413 		if (device_may_wakeup(device))
2414 			flexcan_enable_wakeup_irq(priv, false);
2415 	}
2416 
2417 	return 0;
2418 }
2419 
2420 static const struct dev_pm_ops flexcan_pm_ops = {
2421 	SET_SYSTEM_SLEEP_PM_OPS(flexcan_suspend, flexcan_resume)
2422 	SET_RUNTIME_PM_OPS(flexcan_runtime_suspend, flexcan_runtime_resume, NULL)
2423 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(flexcan_noirq_suspend, flexcan_noirq_resume)
2424 };
2425 
2426 static struct platform_driver flexcan_driver = {
2427 	.driver = {
2428 		.name = DRV_NAME,
2429 		.pm = &flexcan_pm_ops,
2430 		.of_match_table = flexcan_of_match,
2431 	},
2432 	.probe = flexcan_probe,
2433 	.remove = flexcan_remove,
2434 	.id_table = flexcan_id_table,
2435 };
2436 
2437 module_platform_driver(flexcan_driver);
2438 
2439 MODULE_AUTHOR("Sascha Hauer <[email protected]>, "
2440 	      "Marc Kleine-Budde <[email protected]>");
2441 MODULE_LICENSE("GPL v2");
2442 MODULE_DESCRIPTION("CAN port driver for flexcan based chip");
2443