xref: /linux/drivers/net/can/flexcan/flexcan-core.c (revision 9410645520e9b820069761f3450ef6661418e279)
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/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 can_bittiming_const flexcan_bittiming_const = {
390 	.name = DRV_NAME,
391 	.tseg1_min = 4,
392 	.tseg1_max = 16,
393 	.tseg2_min = 2,
394 	.tseg2_max = 8,
395 	.sjw_max = 4,
396 	.brp_min = 1,
397 	.brp_max = 256,
398 	.brp_inc = 1,
399 };
400 
401 static const struct can_bittiming_const flexcan_fd_bittiming_const = {
402 	.name = DRV_NAME,
403 	.tseg1_min = 2,
404 	.tseg1_max = 96,
405 	.tseg2_min = 2,
406 	.tseg2_max = 32,
407 	.sjw_max = 16,
408 	.brp_min = 1,
409 	.brp_max = 1024,
410 	.brp_inc = 1,
411 };
412 
413 static const struct can_bittiming_const flexcan_fd_data_bittiming_const = {
414 	.name = DRV_NAME,
415 	.tseg1_min = 2,
416 	.tseg1_max = 39,
417 	.tseg2_min = 2,
418 	.tseg2_max = 8,
419 	.sjw_max = 4,
420 	.brp_min = 1,
421 	.brp_max = 1024,
422 	.brp_inc = 1,
423 };
424 
425 /* FlexCAN module is essentially modelled as a little-endian IP in most
426  * SoCs, i.e the registers as well as the message buffer areas are
427  * implemented in a little-endian fashion.
428  *
429  * However there are some SoCs (e.g. LS1021A) which implement the FlexCAN
430  * module in a big-endian fashion (i.e the registers as well as the
431  * message buffer areas are implemented in a big-endian way).
432  *
433  * In addition, the FlexCAN module can be found on SoCs having ARM or
434  * PPC cores. So, we need to abstract off the register read/write
435  * functions, ensuring that these cater to all the combinations of module
436  * endianness and underlying CPU endianness.
437  */
flexcan_read_be(void __iomem * addr)438 static inline u32 flexcan_read_be(void __iomem *addr)
439 {
440 	return ioread32be(addr);
441 }
442 
flexcan_write_be(u32 val,void __iomem * addr)443 static inline void flexcan_write_be(u32 val, void __iomem *addr)
444 {
445 	iowrite32be(val, addr);
446 }
447 
flexcan_read_le(void __iomem * addr)448 static inline u32 flexcan_read_le(void __iomem *addr)
449 {
450 	return ioread32(addr);
451 }
452 
flexcan_write_le(u32 val,void __iomem * addr)453 static inline void flexcan_write_le(u32 val, void __iomem *addr)
454 {
455 	iowrite32(val, addr);
456 }
457 
flexcan_get_mb(const struct flexcan_priv * priv,u8 mb_index)458 static struct flexcan_mb __iomem *flexcan_get_mb(const struct flexcan_priv *priv,
459 						 u8 mb_index)
460 {
461 	u8 bank_size;
462 	bool bank;
463 
464 	if (WARN_ON(mb_index >= priv->mb_count))
465 		return NULL;
466 
467 	bank_size = sizeof(priv->regs->mb[0]) / priv->mb_size;
468 
469 	bank = mb_index >= bank_size;
470 	if (bank)
471 		mb_index -= bank_size;
472 
473 	return (struct flexcan_mb __iomem *)
474 		(&priv->regs->mb[bank][priv->mb_size * mb_index]);
475 }
476 
flexcan_low_power_enter_ack(struct flexcan_priv * priv)477 static int flexcan_low_power_enter_ack(struct flexcan_priv *priv)
478 {
479 	struct flexcan_regs __iomem *regs = priv->regs;
480 	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
481 
482 	while (timeout-- && !(priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
483 		udelay(10);
484 
485 	if (!(priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
486 		return -ETIMEDOUT;
487 
488 	return 0;
489 }
490 
flexcan_low_power_exit_ack(struct flexcan_priv * priv)491 static int flexcan_low_power_exit_ack(struct flexcan_priv *priv)
492 {
493 	struct flexcan_regs __iomem *regs = priv->regs;
494 	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
495 
496 	while (timeout-- && (priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
497 		udelay(10);
498 
499 	if (priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK)
500 		return -ETIMEDOUT;
501 
502 	return 0;
503 }
504 
flexcan_enable_wakeup_irq(struct flexcan_priv * priv,bool enable)505 static void flexcan_enable_wakeup_irq(struct flexcan_priv *priv, bool enable)
506 {
507 	struct flexcan_regs __iomem *regs = priv->regs;
508 	u32 reg_mcr;
509 
510 	reg_mcr = priv->read(&regs->mcr);
511 
512 	if (enable)
513 		reg_mcr |= FLEXCAN_MCR_WAK_MSK;
514 	else
515 		reg_mcr &= ~FLEXCAN_MCR_WAK_MSK;
516 
517 	priv->write(reg_mcr, &regs->mcr);
518 }
519 
flexcan_stop_mode_enable_scfw(struct flexcan_priv * priv,bool enabled)520 static int flexcan_stop_mode_enable_scfw(struct flexcan_priv *priv, bool enabled)
521 {
522 	u8 idx = priv->scu_idx;
523 	u32 rsrc_id, val;
524 
525 	rsrc_id = IMX_SC_R_CAN(idx);
526 
527 	if (enabled)
528 		val = 1;
529 	else
530 		val = 0;
531 
532 	/* stop mode request via scu firmware */
533 	return imx_sc_misc_set_control(priv->sc_ipc_handle, rsrc_id,
534 				       IMX_SC_C_IPG_STOP, val);
535 }
536 
flexcan_enter_stop_mode(struct flexcan_priv * priv)537 static inline int flexcan_enter_stop_mode(struct flexcan_priv *priv)
538 {
539 	struct flexcan_regs __iomem *regs = priv->regs;
540 	u32 reg_mcr;
541 	int ret;
542 
543 	reg_mcr = priv->read(&regs->mcr);
544 	reg_mcr |= FLEXCAN_MCR_SLF_WAK;
545 	priv->write(reg_mcr, &regs->mcr);
546 
547 	/* enable stop request */
548 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW) {
549 		ret = flexcan_stop_mode_enable_scfw(priv, true);
550 		if (ret < 0)
551 			return ret;
552 	} else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR) {
553 		regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr,
554 				   1 << priv->stm.req_bit, 1 << priv->stm.req_bit);
555 	} else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI) {
556 		/* For the SCMI mode, driver do nothing, ATF will send request to
557 		 * SM(system manager, M33 core) through SCMI protocol after linux
558 		 * suspend. Once SM get this request, it will send IPG_STOP signal
559 		 * to Flex_CAN, let CAN in STOP mode.
560 		 */
561 		return 0;
562 	}
563 
564 	return flexcan_low_power_enter_ack(priv);
565 }
566 
flexcan_exit_stop_mode(struct flexcan_priv * priv)567 static inline int flexcan_exit_stop_mode(struct flexcan_priv *priv)
568 {
569 	struct flexcan_regs __iomem *regs = priv->regs;
570 	u32 reg_mcr;
571 	int ret;
572 
573 	/* Remove stop request, for FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI,
574 	 * do nothing here, because ATF already send request to SM before
575 	 * linux resume. Once SM get this request, it will deassert the
576 	 * IPG_STOP signal to Flex_CAN.
577 	 */
578 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW) {
579 		ret = flexcan_stop_mode_enable_scfw(priv, false);
580 		if (ret < 0)
581 			return ret;
582 	} else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR) {
583 		regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr,
584 				   1 << priv->stm.req_bit, 0);
585 	}
586 
587 	reg_mcr = priv->read(&regs->mcr);
588 	reg_mcr &= ~FLEXCAN_MCR_SLF_WAK;
589 	priv->write(reg_mcr, &regs->mcr);
590 
591 	return flexcan_low_power_exit_ack(priv);
592 }
593 
flexcan_error_irq_enable(const struct flexcan_priv * priv)594 static inline void flexcan_error_irq_enable(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 
flexcan_error_irq_disable(const struct flexcan_priv * priv)602 static inline void flexcan_error_irq_disable(const struct flexcan_priv *priv)
603 {
604 	struct flexcan_regs __iomem *regs = priv->regs;
605 	u32 reg_ctrl = (priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_MSK);
606 
607 	priv->write(reg_ctrl, &regs->ctrl);
608 }
609 
flexcan_clks_enable(const struct flexcan_priv * priv)610 static int flexcan_clks_enable(const struct flexcan_priv *priv)
611 {
612 	int err = 0;
613 
614 	if (priv->clk_ipg) {
615 		err = clk_prepare_enable(priv->clk_ipg);
616 		if (err)
617 			return err;
618 	}
619 
620 	if (priv->clk_per) {
621 		err = clk_prepare_enable(priv->clk_per);
622 		if (err)
623 			clk_disable_unprepare(priv->clk_ipg);
624 	}
625 
626 	return err;
627 }
628 
flexcan_clks_disable(const struct flexcan_priv * priv)629 static void flexcan_clks_disable(const struct flexcan_priv *priv)
630 {
631 	clk_disable_unprepare(priv->clk_per);
632 	clk_disable_unprepare(priv->clk_ipg);
633 }
634 
flexcan_transceiver_enable(const struct flexcan_priv * priv)635 static inline int flexcan_transceiver_enable(const struct flexcan_priv *priv)
636 {
637 	if (!priv->reg_xceiver)
638 		return 0;
639 
640 	return regulator_enable(priv->reg_xceiver);
641 }
642 
flexcan_transceiver_disable(const struct flexcan_priv * priv)643 static inline int flexcan_transceiver_disable(const struct flexcan_priv *priv)
644 {
645 	if (!priv->reg_xceiver)
646 		return 0;
647 
648 	return regulator_disable(priv->reg_xceiver);
649 }
650 
flexcan_chip_enable(struct flexcan_priv * priv)651 static int flexcan_chip_enable(struct flexcan_priv *priv)
652 {
653 	struct flexcan_regs __iomem *regs = priv->regs;
654 	u32 reg;
655 
656 	reg = priv->read(&regs->mcr);
657 	reg &= ~FLEXCAN_MCR_MDIS;
658 	priv->write(reg, &regs->mcr);
659 
660 	return flexcan_low_power_exit_ack(priv);
661 }
662 
flexcan_chip_disable(struct flexcan_priv * priv)663 static int flexcan_chip_disable(struct flexcan_priv *priv)
664 {
665 	struct flexcan_regs __iomem *regs = priv->regs;
666 	u32 reg;
667 
668 	reg = priv->read(&regs->mcr);
669 	reg |= FLEXCAN_MCR_MDIS;
670 	priv->write(reg, &regs->mcr);
671 
672 	return flexcan_low_power_enter_ack(priv);
673 }
674 
flexcan_chip_freeze(struct flexcan_priv * priv)675 static int flexcan_chip_freeze(struct flexcan_priv *priv)
676 {
677 	struct flexcan_regs __iomem *regs = priv->regs;
678 	unsigned int timeout;
679 	u32 bitrate = priv->can.bittiming.bitrate;
680 	u32 reg;
681 
682 	if (bitrate)
683 		timeout = 1000 * 1000 * 10 / bitrate;
684 	else
685 		timeout = FLEXCAN_TIMEOUT_US / 10;
686 
687 	reg = priv->read(&regs->mcr);
688 	reg |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_HALT;
689 	priv->write(reg, &regs->mcr);
690 
691 	while (timeout-- && !(priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
692 		udelay(100);
693 
694 	if (!(priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
695 		return -ETIMEDOUT;
696 
697 	return 0;
698 }
699 
flexcan_chip_unfreeze(struct flexcan_priv * priv)700 static int flexcan_chip_unfreeze(struct flexcan_priv *priv)
701 {
702 	struct flexcan_regs __iomem *regs = priv->regs;
703 	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
704 	u32 reg;
705 
706 	reg = priv->read(&regs->mcr);
707 	reg &= ~FLEXCAN_MCR_HALT;
708 	priv->write(reg, &regs->mcr);
709 
710 	while (timeout-- && (priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
711 		udelay(10);
712 
713 	if (priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK)
714 		return -ETIMEDOUT;
715 
716 	return 0;
717 }
718 
flexcan_chip_softreset(struct flexcan_priv * priv)719 static int flexcan_chip_softreset(struct flexcan_priv *priv)
720 {
721 	struct flexcan_regs __iomem *regs = priv->regs;
722 	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
723 
724 	priv->write(FLEXCAN_MCR_SOFTRST, &regs->mcr);
725 	while (timeout-- && (priv->read(&regs->mcr) & FLEXCAN_MCR_SOFTRST))
726 		udelay(10);
727 
728 	if (priv->read(&regs->mcr) & FLEXCAN_MCR_SOFTRST)
729 		return -ETIMEDOUT;
730 
731 	return 0;
732 }
733 
__flexcan_get_berr_counter(const struct net_device * dev,struct can_berr_counter * bec)734 static int __flexcan_get_berr_counter(const struct net_device *dev,
735 				      struct can_berr_counter *bec)
736 {
737 	const struct flexcan_priv *priv = netdev_priv(dev);
738 	struct flexcan_regs __iomem *regs = priv->regs;
739 	u32 reg = priv->read(&regs->ecr);
740 
741 	bec->txerr = (reg >> 0) & 0xff;
742 	bec->rxerr = (reg >> 8) & 0xff;
743 
744 	return 0;
745 }
746 
flexcan_get_berr_counter(const struct net_device * dev,struct can_berr_counter * bec)747 static int flexcan_get_berr_counter(const struct net_device *dev,
748 				    struct can_berr_counter *bec)
749 {
750 	const struct flexcan_priv *priv = netdev_priv(dev);
751 	int err;
752 
753 	err = pm_runtime_resume_and_get(priv->dev);
754 	if (err < 0)
755 		return err;
756 
757 	err = __flexcan_get_berr_counter(dev, bec);
758 
759 	pm_runtime_put(priv->dev);
760 
761 	return err;
762 }
763 
flexcan_start_xmit(struct sk_buff * skb,struct net_device * dev)764 static netdev_tx_t flexcan_start_xmit(struct sk_buff *skb, struct net_device *dev)
765 {
766 	const struct flexcan_priv *priv = netdev_priv(dev);
767 	struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
768 	u32 can_id;
769 	u32 data;
770 	u32 ctrl = FLEXCAN_MB_CODE_TX_DATA | ((can_fd_len2dlc(cfd->len)) << 16);
771 	int i;
772 
773 	if (can_dev_dropped_skb(dev, skb))
774 		return NETDEV_TX_OK;
775 
776 	netif_stop_queue(dev);
777 
778 	if (cfd->can_id & CAN_EFF_FLAG) {
779 		can_id = cfd->can_id & CAN_EFF_MASK;
780 		ctrl |= FLEXCAN_MB_CNT_IDE | FLEXCAN_MB_CNT_SRR;
781 	} else {
782 		can_id = (cfd->can_id & CAN_SFF_MASK) << 18;
783 	}
784 
785 	if (cfd->can_id & CAN_RTR_FLAG)
786 		ctrl |= FLEXCAN_MB_CNT_RTR;
787 
788 	if (can_is_canfd_skb(skb)) {
789 		ctrl |= FLEXCAN_MB_CNT_EDL;
790 
791 		if (cfd->flags & CANFD_BRS)
792 			ctrl |= FLEXCAN_MB_CNT_BRS;
793 	}
794 
795 	for (i = 0; i < cfd->len; i += sizeof(u32)) {
796 		data = be32_to_cpup((__be32 *)&cfd->data[i]);
797 		priv->write(data, &priv->tx_mb->data[i / sizeof(u32)]);
798 	}
799 
800 	can_put_echo_skb(skb, dev, 0, 0);
801 
802 	priv->write(can_id, &priv->tx_mb->can_id);
803 	priv->write(ctrl, &priv->tx_mb->can_ctrl);
804 
805 	/* Errata ERR005829 step8:
806 	 * Write twice INACTIVE(0x8) code to first MB.
807 	 */
808 	priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
809 		    &priv->tx_mb_reserved->can_ctrl);
810 	priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
811 		    &priv->tx_mb_reserved->can_ctrl);
812 
813 	return NETDEV_TX_OK;
814 }
815 
flexcan_irq_bus_err(struct net_device * dev,u32 reg_esr)816 static void flexcan_irq_bus_err(struct net_device *dev, u32 reg_esr)
817 {
818 	struct flexcan_priv *priv = netdev_priv(dev);
819 	struct flexcan_regs __iomem *regs = priv->regs;
820 	struct sk_buff *skb;
821 	struct can_frame *cf;
822 	bool rx_errors = false, tx_errors = false;
823 	u32 timestamp;
824 	int err;
825 
826 	timestamp = priv->read(&regs->timer) << 16;
827 
828 	skb = alloc_can_err_skb(dev, &cf);
829 	if (unlikely(!skb))
830 		return;
831 
832 	cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
833 
834 	if (reg_esr & FLEXCAN_ESR_BIT1_ERR) {
835 		netdev_dbg(dev, "BIT1_ERR irq\n");
836 		cf->data[2] |= CAN_ERR_PROT_BIT1;
837 		tx_errors = true;
838 	}
839 	if (reg_esr & FLEXCAN_ESR_BIT0_ERR) {
840 		netdev_dbg(dev, "BIT0_ERR irq\n");
841 		cf->data[2] |= CAN_ERR_PROT_BIT0;
842 		tx_errors = true;
843 	}
844 	if (reg_esr & FLEXCAN_ESR_ACK_ERR) {
845 		netdev_dbg(dev, "ACK_ERR irq\n");
846 		cf->can_id |= CAN_ERR_ACK;
847 		cf->data[3] = CAN_ERR_PROT_LOC_ACK;
848 		tx_errors = true;
849 	}
850 	if (reg_esr & FLEXCAN_ESR_CRC_ERR) {
851 		netdev_dbg(dev, "CRC_ERR irq\n");
852 		cf->data[2] |= CAN_ERR_PROT_BIT;
853 		cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
854 		rx_errors = true;
855 	}
856 	if (reg_esr & FLEXCAN_ESR_FRM_ERR) {
857 		netdev_dbg(dev, "FRM_ERR irq\n");
858 		cf->data[2] |= CAN_ERR_PROT_FORM;
859 		rx_errors = true;
860 	}
861 	if (reg_esr & FLEXCAN_ESR_STF_ERR) {
862 		netdev_dbg(dev, "STF_ERR irq\n");
863 		cf->data[2] |= CAN_ERR_PROT_STUFF;
864 		rx_errors = true;
865 	}
866 
867 	priv->can.can_stats.bus_error++;
868 	if (rx_errors)
869 		dev->stats.rx_errors++;
870 	if (tx_errors)
871 		dev->stats.tx_errors++;
872 
873 	err = can_rx_offload_queue_timestamp(&priv->offload, skb, timestamp);
874 	if (err)
875 		dev->stats.rx_fifo_errors++;
876 }
877 
flexcan_irq_state(struct net_device * dev,u32 reg_esr)878 static void flexcan_irq_state(struct net_device *dev, u32 reg_esr)
879 {
880 	struct flexcan_priv *priv = netdev_priv(dev);
881 	struct flexcan_regs __iomem *regs = priv->regs;
882 	struct sk_buff *skb;
883 	struct can_frame *cf;
884 	enum can_state new_state, rx_state, tx_state;
885 	int flt;
886 	struct can_berr_counter bec;
887 	u32 timestamp;
888 	int err;
889 
890 	flt = reg_esr & FLEXCAN_ESR_FLT_CONF_MASK;
891 	if (likely(flt == FLEXCAN_ESR_FLT_CONF_ACTIVE)) {
892 		tx_state = unlikely(reg_esr & FLEXCAN_ESR_TX_WRN) ?
893 			CAN_STATE_ERROR_WARNING : CAN_STATE_ERROR_ACTIVE;
894 		rx_state = unlikely(reg_esr & FLEXCAN_ESR_RX_WRN) ?
895 			CAN_STATE_ERROR_WARNING : CAN_STATE_ERROR_ACTIVE;
896 		new_state = max(tx_state, rx_state);
897 	} else {
898 		__flexcan_get_berr_counter(dev, &bec);
899 		new_state = flt == FLEXCAN_ESR_FLT_CONF_PASSIVE ?
900 			CAN_STATE_ERROR_PASSIVE : CAN_STATE_BUS_OFF;
901 		rx_state = bec.rxerr >= bec.txerr ? new_state : 0;
902 		tx_state = bec.rxerr <= bec.txerr ? new_state : 0;
903 	}
904 
905 	/* state hasn't changed */
906 	if (likely(new_state == priv->can.state))
907 		return;
908 
909 	timestamp = priv->read(&regs->timer) << 16;
910 
911 	skb = alloc_can_err_skb(dev, &cf);
912 	if (unlikely(!skb))
913 		return;
914 
915 	can_change_state(dev, cf, tx_state, rx_state);
916 
917 	if (unlikely(new_state == CAN_STATE_BUS_OFF))
918 		can_bus_off(dev);
919 
920 	err = can_rx_offload_queue_timestamp(&priv->offload, skb, timestamp);
921 	if (err)
922 		dev->stats.rx_fifo_errors++;
923 }
924 
flexcan_read64_mask(struct flexcan_priv * priv,void __iomem * addr,u64 mask)925 static inline u64 flexcan_read64_mask(struct flexcan_priv *priv, void __iomem *addr, u64 mask)
926 {
927 	u64 reg = 0;
928 
929 	if (upper_32_bits(mask))
930 		reg = (u64)priv->read(addr - 4) << 32;
931 	if (lower_32_bits(mask))
932 		reg |= priv->read(addr);
933 
934 	return reg & mask;
935 }
936 
flexcan_write64(struct flexcan_priv * priv,u64 val,void __iomem * addr)937 static inline void flexcan_write64(struct flexcan_priv *priv, u64 val, void __iomem *addr)
938 {
939 	if (upper_32_bits(val))
940 		priv->write(upper_32_bits(val), addr - 4);
941 	if (lower_32_bits(val))
942 		priv->write(lower_32_bits(val), addr);
943 }
944 
flexcan_read_reg_iflag_rx(struct flexcan_priv * priv)945 static inline u64 flexcan_read_reg_iflag_rx(struct flexcan_priv *priv)
946 {
947 	return flexcan_read64_mask(priv, &priv->regs->iflag1, priv->rx_mask);
948 }
949 
flexcan_read_reg_iflag_tx(struct flexcan_priv * priv)950 static inline u64 flexcan_read_reg_iflag_tx(struct flexcan_priv *priv)
951 {
952 	return flexcan_read64_mask(priv, &priv->regs->iflag1, priv->tx_mask);
953 }
954 
rx_offload_to_priv(struct can_rx_offload * offload)955 static inline struct flexcan_priv *rx_offload_to_priv(struct can_rx_offload *offload)
956 {
957 	return container_of(offload, struct flexcan_priv, offload);
958 }
959 
flexcan_mailbox_read(struct can_rx_offload * offload,unsigned int n,u32 * timestamp,bool drop)960 static struct sk_buff *flexcan_mailbox_read(struct can_rx_offload *offload,
961 					    unsigned int n, u32 *timestamp,
962 					    bool drop)
963 {
964 	struct flexcan_priv *priv = rx_offload_to_priv(offload);
965 	struct flexcan_regs __iomem *regs = priv->regs;
966 	struct flexcan_mb __iomem *mb;
967 	struct sk_buff *skb;
968 	struct canfd_frame *cfd;
969 	u32 reg_ctrl, reg_id, reg_iflag1;
970 	int i;
971 
972 	mb = flexcan_get_mb(priv, n);
973 
974 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX) {
975 		u32 code;
976 
977 		do {
978 			reg_ctrl = priv->read(&mb->can_ctrl);
979 		} while (reg_ctrl & FLEXCAN_MB_CODE_RX_BUSY_BIT);
980 
981 		/* is this MB empty? */
982 		code = reg_ctrl & FLEXCAN_MB_CODE_MASK;
983 		if ((code != FLEXCAN_MB_CODE_RX_FULL) &&
984 		    (code != FLEXCAN_MB_CODE_RX_OVERRUN))
985 			return NULL;
986 
987 		if (code == FLEXCAN_MB_CODE_RX_OVERRUN) {
988 			/* This MB was overrun, we lost data */
989 			offload->dev->stats.rx_over_errors++;
990 			offload->dev->stats.rx_errors++;
991 		}
992 	} else {
993 		reg_iflag1 = priv->read(&regs->iflag1);
994 		if (!(reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE))
995 			return NULL;
996 
997 		reg_ctrl = priv->read(&mb->can_ctrl);
998 	}
999 
1000 	if (unlikely(drop)) {
1001 		skb = ERR_PTR(-ENOBUFS);
1002 		goto mark_as_read;
1003 	}
1004 
1005 	if (reg_ctrl & FLEXCAN_MB_CNT_EDL)
1006 		skb = alloc_canfd_skb(offload->dev, &cfd);
1007 	else
1008 		skb = alloc_can_skb(offload->dev, (struct can_frame **)&cfd);
1009 	if (unlikely(!skb)) {
1010 		skb = ERR_PTR(-ENOMEM);
1011 		goto mark_as_read;
1012 	}
1013 
1014 	/* increase timstamp to full 32 bit */
1015 	*timestamp = reg_ctrl << 16;
1016 
1017 	reg_id = priv->read(&mb->can_id);
1018 	if (reg_ctrl & FLEXCAN_MB_CNT_IDE)
1019 		cfd->can_id = ((reg_id >> 0) & CAN_EFF_MASK) | CAN_EFF_FLAG;
1020 	else
1021 		cfd->can_id = (reg_id >> 18) & CAN_SFF_MASK;
1022 
1023 	if (reg_ctrl & FLEXCAN_MB_CNT_EDL) {
1024 		cfd->len = can_fd_dlc2len((reg_ctrl >> 16) & 0xf);
1025 
1026 		if (reg_ctrl & FLEXCAN_MB_CNT_BRS)
1027 			cfd->flags |= CANFD_BRS;
1028 	} else {
1029 		cfd->len = can_cc_dlc2len((reg_ctrl >> 16) & 0xf);
1030 
1031 		if (reg_ctrl & FLEXCAN_MB_CNT_RTR)
1032 			cfd->can_id |= CAN_RTR_FLAG;
1033 	}
1034 
1035 	if (reg_ctrl & FLEXCAN_MB_CNT_ESI)
1036 		cfd->flags |= CANFD_ESI;
1037 
1038 	for (i = 0; i < cfd->len; i += sizeof(u32)) {
1039 		__be32 data = cpu_to_be32(priv->read(&mb->data[i / sizeof(u32)]));
1040 		*(__be32 *)(cfd->data + i) = data;
1041 	}
1042 
1043  mark_as_read:
1044 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX)
1045 		flexcan_write64(priv, FLEXCAN_IFLAG_MB(n), &regs->iflag1);
1046 	else
1047 		priv->write(FLEXCAN_IFLAG_RX_FIFO_AVAILABLE, &regs->iflag1);
1048 
1049 	/* Read the Free Running Timer. It is optional but recommended
1050 	 * to unlock Mailbox as soon as possible and make it available
1051 	 * for reception.
1052 	 */
1053 	priv->read(&regs->timer);
1054 
1055 	return skb;
1056 }
1057 
flexcan_irq(int irq,void * dev_id)1058 static irqreturn_t flexcan_irq(int irq, void *dev_id)
1059 {
1060 	struct net_device *dev = dev_id;
1061 	struct net_device_stats *stats = &dev->stats;
1062 	struct flexcan_priv *priv = netdev_priv(dev);
1063 	struct flexcan_regs __iomem *regs = priv->regs;
1064 	irqreturn_t handled = IRQ_NONE;
1065 	u64 reg_iflag_tx;
1066 	u32 reg_esr;
1067 	enum can_state last_state = priv->can.state;
1068 
1069 	/* reception interrupt */
1070 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX) {
1071 		u64 reg_iflag_rx;
1072 		int ret;
1073 
1074 		while ((reg_iflag_rx = flexcan_read_reg_iflag_rx(priv))) {
1075 			handled = IRQ_HANDLED;
1076 			ret = can_rx_offload_irq_offload_timestamp(&priv->offload,
1077 								   reg_iflag_rx);
1078 			if (!ret)
1079 				break;
1080 		}
1081 	} else {
1082 		u32 reg_iflag1;
1083 
1084 		reg_iflag1 = priv->read(&regs->iflag1);
1085 		if (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE) {
1086 			handled = IRQ_HANDLED;
1087 			can_rx_offload_irq_offload_fifo(&priv->offload);
1088 		}
1089 
1090 		/* FIFO overflow interrupt */
1091 		if (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_OVERFLOW) {
1092 			handled = IRQ_HANDLED;
1093 			priv->write(FLEXCAN_IFLAG_RX_FIFO_OVERFLOW,
1094 				    &regs->iflag1);
1095 			dev->stats.rx_over_errors++;
1096 			dev->stats.rx_errors++;
1097 		}
1098 	}
1099 
1100 	reg_iflag_tx = flexcan_read_reg_iflag_tx(priv);
1101 
1102 	/* transmission complete interrupt */
1103 	if (reg_iflag_tx & priv->tx_mask) {
1104 		u32 reg_ctrl = priv->read(&priv->tx_mb->can_ctrl);
1105 
1106 		handled = IRQ_HANDLED;
1107 		stats->tx_bytes +=
1108 			can_rx_offload_get_echo_skb_queue_timestamp(&priv->offload, 0,
1109 								    reg_ctrl << 16, NULL);
1110 		stats->tx_packets++;
1111 
1112 		/* after sending a RTR frame MB is in RX mode */
1113 		priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
1114 			    &priv->tx_mb->can_ctrl);
1115 		flexcan_write64(priv, priv->tx_mask, &regs->iflag1);
1116 		netif_wake_queue(dev);
1117 	}
1118 
1119 	reg_esr = priv->read(&regs->esr);
1120 
1121 	/* ACK all bus error, state change and wake IRQ sources */
1122 	if (reg_esr & (FLEXCAN_ESR_ALL_INT | FLEXCAN_ESR_WAK_INT)) {
1123 		handled = IRQ_HANDLED;
1124 		priv->write(reg_esr & (FLEXCAN_ESR_ALL_INT | FLEXCAN_ESR_WAK_INT), &regs->esr);
1125 	}
1126 
1127 	/* state change interrupt or broken error state quirk fix is enabled */
1128 	if ((reg_esr & FLEXCAN_ESR_ERR_STATE) ||
1129 	    (priv->devtype_data.quirks & (FLEXCAN_QUIRK_BROKEN_WERR_STATE |
1130 					   FLEXCAN_QUIRK_BROKEN_PERR_STATE)))
1131 		flexcan_irq_state(dev, reg_esr);
1132 
1133 	/* bus error IRQ - handle if bus error reporting is activated */
1134 	if ((reg_esr & FLEXCAN_ESR_ERR_BUS) &&
1135 	    (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
1136 		flexcan_irq_bus_err(dev, reg_esr);
1137 
1138 	/* availability of error interrupt among state transitions in case
1139 	 * bus error reporting is de-activated and
1140 	 * FLEXCAN_QUIRK_BROKEN_PERR_STATE is enabled:
1141 	 *  +--------------------------------------------------------------+
1142 	 *  | +----------------------------------------------+ [stopped /  |
1143 	 *  | |                                              |  sleeping] -+
1144 	 *  +-+-> active <-> warning <-> passive -> bus off -+
1145 	 *        ___________^^^^^^^^^^^^_______________________________
1146 	 *        disabled(1)  enabled             disabled
1147 	 *
1148 	 * (1): enabled if FLEXCAN_QUIRK_BROKEN_WERR_STATE is enabled
1149 	 */
1150 	if ((last_state != priv->can.state) &&
1151 	    (priv->devtype_data.quirks & FLEXCAN_QUIRK_BROKEN_PERR_STATE) &&
1152 	    !(priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)) {
1153 		switch (priv->can.state) {
1154 		case CAN_STATE_ERROR_ACTIVE:
1155 			if (priv->devtype_data.quirks &
1156 			    FLEXCAN_QUIRK_BROKEN_WERR_STATE)
1157 				flexcan_error_irq_enable(priv);
1158 			else
1159 				flexcan_error_irq_disable(priv);
1160 			break;
1161 
1162 		case CAN_STATE_ERROR_WARNING:
1163 			flexcan_error_irq_enable(priv);
1164 			break;
1165 
1166 		case CAN_STATE_ERROR_PASSIVE:
1167 		case CAN_STATE_BUS_OFF:
1168 			flexcan_error_irq_disable(priv);
1169 			break;
1170 
1171 		default:
1172 			break;
1173 		}
1174 	}
1175 
1176 	if (handled)
1177 		can_rx_offload_irq_finish(&priv->offload);
1178 
1179 	return handled;
1180 }
1181 
flexcan_set_bittiming_ctrl(const struct net_device * dev)1182 static void flexcan_set_bittiming_ctrl(const struct net_device *dev)
1183 {
1184 	const struct flexcan_priv *priv = netdev_priv(dev);
1185 	const struct can_bittiming *bt = &priv->can.bittiming;
1186 	struct flexcan_regs __iomem *regs = priv->regs;
1187 	u32 reg;
1188 
1189 	reg = priv->read(&regs->ctrl);
1190 	reg &= ~(FLEXCAN_CTRL_PRESDIV(0xff) |
1191 		 FLEXCAN_CTRL_RJW(0x3) |
1192 		 FLEXCAN_CTRL_PSEG1(0x7) |
1193 		 FLEXCAN_CTRL_PSEG2(0x7) |
1194 		 FLEXCAN_CTRL_PROPSEG(0x7));
1195 
1196 	reg |= FLEXCAN_CTRL_PRESDIV(bt->brp - 1) |
1197 		FLEXCAN_CTRL_PSEG1(bt->phase_seg1 - 1) |
1198 		FLEXCAN_CTRL_PSEG2(bt->phase_seg2 - 1) |
1199 		FLEXCAN_CTRL_RJW(bt->sjw - 1) |
1200 		FLEXCAN_CTRL_PROPSEG(bt->prop_seg - 1);
1201 
1202 	netdev_dbg(dev, "writing ctrl=0x%08x\n", reg);
1203 	priv->write(reg, &regs->ctrl);
1204 
1205 	/* print chip status */
1206 	netdev_dbg(dev, "%s: mcr=0x%08x ctrl=0x%08x\n", __func__,
1207 		   priv->read(&regs->mcr), priv->read(&regs->ctrl));
1208 }
1209 
flexcan_set_bittiming_cbt(const struct net_device * dev)1210 static void flexcan_set_bittiming_cbt(const struct net_device *dev)
1211 {
1212 	struct flexcan_priv *priv = netdev_priv(dev);
1213 	struct can_bittiming *bt = &priv->can.bittiming;
1214 	struct can_bittiming *dbt = &priv->can.data_bittiming;
1215 	struct flexcan_regs __iomem *regs = priv->regs;
1216 	u32 reg_cbt, reg_fdctrl;
1217 
1218 	/* CBT */
1219 	/* CBT[EPSEG1] is 5 bit long and CBT[EPROPSEG] is 6 bit
1220 	 * long. The can_calc_bittiming() tries to divide the tseg1
1221 	 * equally between phase_seg1 and prop_seg, which may not fit
1222 	 * in CBT register. Therefore, if phase_seg1 is more than
1223 	 * possible value, increase prop_seg and decrease phase_seg1.
1224 	 */
1225 	if (bt->phase_seg1 > 0x20) {
1226 		bt->prop_seg += (bt->phase_seg1 - 0x20);
1227 		bt->phase_seg1 = 0x20;
1228 	}
1229 
1230 	reg_cbt = FLEXCAN_CBT_BTF |
1231 		FIELD_PREP(FLEXCAN_CBT_EPRESDIV_MASK, bt->brp - 1) |
1232 		FIELD_PREP(FLEXCAN_CBT_ERJW_MASK, bt->sjw - 1) |
1233 		FIELD_PREP(FLEXCAN_CBT_EPROPSEG_MASK, bt->prop_seg - 1) |
1234 		FIELD_PREP(FLEXCAN_CBT_EPSEG1_MASK, bt->phase_seg1 - 1) |
1235 		FIELD_PREP(FLEXCAN_CBT_EPSEG2_MASK, bt->phase_seg2 - 1);
1236 
1237 	netdev_dbg(dev, "writing cbt=0x%08x\n", reg_cbt);
1238 	priv->write(reg_cbt, &regs->cbt);
1239 
1240 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
1241 		u32 reg_fdcbt, reg_ctrl2;
1242 
1243 		if (bt->brp != dbt->brp)
1244 			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",
1245 				    dbt->brp, bt->brp);
1246 
1247 		/* FDCBT */
1248 		/* FDCBT[FPSEG1] is 3 bit long and FDCBT[FPROPSEG] is
1249 		 * 5 bit long. The can_calc_bittiming tries to divide
1250 		 * the tseg1 equally between phase_seg1 and prop_seg,
1251 		 * which may not fit in FDCBT register. Therefore, if
1252 		 * phase_seg1 is more than possible value, increase
1253 		 * prop_seg and decrease phase_seg1
1254 		 */
1255 		if (dbt->phase_seg1 > 0x8) {
1256 			dbt->prop_seg += (dbt->phase_seg1 - 0x8);
1257 			dbt->phase_seg1 = 0x8;
1258 		}
1259 
1260 		reg_fdcbt = priv->read(&regs->fdcbt);
1261 		reg_fdcbt &= ~(FIELD_PREP(FLEXCAN_FDCBT_FPRESDIV_MASK, 0x3ff) |
1262 			       FIELD_PREP(FLEXCAN_FDCBT_FRJW_MASK, 0x7) |
1263 			       FIELD_PREP(FLEXCAN_FDCBT_FPROPSEG_MASK, 0x1f) |
1264 			       FIELD_PREP(FLEXCAN_FDCBT_FPSEG1_MASK, 0x7) |
1265 			       FIELD_PREP(FLEXCAN_FDCBT_FPSEG2_MASK, 0x7));
1266 
1267 		reg_fdcbt |= FIELD_PREP(FLEXCAN_FDCBT_FPRESDIV_MASK, dbt->brp - 1) |
1268 			FIELD_PREP(FLEXCAN_FDCBT_FRJW_MASK, dbt->sjw - 1) |
1269 			FIELD_PREP(FLEXCAN_FDCBT_FPROPSEG_MASK, dbt->prop_seg) |
1270 			FIELD_PREP(FLEXCAN_FDCBT_FPSEG1_MASK, dbt->phase_seg1 - 1) |
1271 			FIELD_PREP(FLEXCAN_FDCBT_FPSEG2_MASK, dbt->phase_seg2 - 1);
1272 
1273 		netdev_dbg(dev, "writing fdcbt=0x%08x\n", reg_fdcbt);
1274 		priv->write(reg_fdcbt, &regs->fdcbt);
1275 
1276 		/* CTRL2 */
1277 		reg_ctrl2 = priv->read(&regs->ctrl2);
1278 		reg_ctrl2 &= ~FLEXCAN_CTRL2_ISOCANFDEN;
1279 		if (!(priv->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO))
1280 			reg_ctrl2 |= FLEXCAN_CTRL2_ISOCANFDEN;
1281 
1282 		netdev_dbg(dev, "writing ctrl2=0x%08x\n", reg_ctrl2);
1283 		priv->write(reg_ctrl2, &regs->ctrl2);
1284 	}
1285 
1286 	/* FDCTRL */
1287 	reg_fdctrl = priv->read(&regs->fdctrl);
1288 	reg_fdctrl &= ~(FLEXCAN_FDCTRL_FDRATE |
1289 			FIELD_PREP(FLEXCAN_FDCTRL_TDCOFF, 0x1f));
1290 
1291 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
1292 		reg_fdctrl |= FLEXCAN_FDCTRL_FDRATE;
1293 
1294 		if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) {
1295 			/* TDC must be disabled for Loop Back mode */
1296 			reg_fdctrl &= ~FLEXCAN_FDCTRL_TDCEN;
1297 		} else {
1298 			reg_fdctrl |= FLEXCAN_FDCTRL_TDCEN |
1299 				FIELD_PREP(FLEXCAN_FDCTRL_TDCOFF,
1300 					   ((dbt->phase_seg1 - 1) +
1301 					    dbt->prop_seg + 2) *
1302 					   ((dbt->brp - 1 ) + 1));
1303 		}
1304 	}
1305 
1306 	netdev_dbg(dev, "writing fdctrl=0x%08x\n", reg_fdctrl);
1307 	priv->write(reg_fdctrl, &regs->fdctrl);
1308 
1309 	netdev_dbg(dev, "%s: mcr=0x%08x ctrl=0x%08x ctrl2=0x%08x fdctrl=0x%08x cbt=0x%08x fdcbt=0x%08x\n",
1310 		   __func__,
1311 		   priv->read(&regs->mcr), priv->read(&regs->ctrl),
1312 		   priv->read(&regs->ctrl2), priv->read(&regs->fdctrl),
1313 		   priv->read(&regs->cbt), priv->read(&regs->fdcbt));
1314 }
1315 
flexcan_set_bittiming(struct net_device * dev)1316 static void flexcan_set_bittiming(struct net_device *dev)
1317 {
1318 	const struct flexcan_priv *priv = netdev_priv(dev);
1319 	struct flexcan_regs __iomem *regs = priv->regs;
1320 	u32 reg;
1321 
1322 	reg = priv->read(&regs->ctrl);
1323 	reg &= ~(FLEXCAN_CTRL_LPB | FLEXCAN_CTRL_SMP |
1324 		 FLEXCAN_CTRL_LOM);
1325 
1326 	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
1327 		reg |= FLEXCAN_CTRL_LPB;
1328 	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
1329 		reg |= FLEXCAN_CTRL_LOM;
1330 	if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
1331 		reg |= FLEXCAN_CTRL_SMP;
1332 
1333 	netdev_dbg(dev, "writing ctrl=0x%08x\n", reg);
1334 	priv->write(reg, &regs->ctrl);
1335 
1336 	if (priv->can.ctrlmode_supported & CAN_CTRLMODE_FD)
1337 		return flexcan_set_bittiming_cbt(dev);
1338 	else
1339 		return flexcan_set_bittiming_ctrl(dev);
1340 }
1341 
flexcan_ram_init(struct net_device * dev)1342 static void flexcan_ram_init(struct net_device *dev)
1343 {
1344 	struct flexcan_priv *priv = netdev_priv(dev);
1345 	struct flexcan_regs __iomem *regs = priv->regs;
1346 	u32 reg_ctrl2;
1347 
1348 	/* 11.8.3.13 Detection and correction of memory errors:
1349 	 * CTRL2[WRMFRZ] grants write access to all memory positions
1350 	 * that require initialization, ranging from 0x080 to 0xADF
1351 	 * and from 0xF28 to 0xFFF when the CAN FD feature is enabled.
1352 	 * The RXMGMASK, RX14MASK, RX15MASK, and RXFGMASK registers
1353 	 * need to be initialized as well. MCR[RFEN] must not be set
1354 	 * during memory initialization.
1355 	 */
1356 	reg_ctrl2 = priv->read(&regs->ctrl2);
1357 	reg_ctrl2 |= FLEXCAN_CTRL2_WRMFRZ;
1358 	priv->write(reg_ctrl2, &regs->ctrl2);
1359 
1360 	memset_io(&regs->init, 0, sizeof(regs->init));
1361 
1362 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
1363 		memset_io(&regs->init_fd, 0, sizeof(regs->init_fd));
1364 
1365 	reg_ctrl2 &= ~FLEXCAN_CTRL2_WRMFRZ;
1366 	priv->write(reg_ctrl2, &regs->ctrl2);
1367 }
1368 
flexcan_rx_offload_setup(struct net_device * dev)1369 static int flexcan_rx_offload_setup(struct net_device *dev)
1370 {
1371 	struct flexcan_priv *priv = netdev_priv(dev);
1372 	int err;
1373 
1374 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
1375 		priv->mb_size = sizeof(struct flexcan_mb) + CANFD_MAX_DLEN;
1376 	else
1377 		priv->mb_size = sizeof(struct flexcan_mb) + CAN_MAX_DLEN;
1378 
1379 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_NR_MB_16)
1380 		priv->mb_count = 16;
1381 	else
1382 		priv->mb_count = (sizeof(priv->regs->mb[0]) / priv->mb_size) +
1383 				 (sizeof(priv->regs->mb[1]) / priv->mb_size);
1384 
1385 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX)
1386 		priv->tx_mb_reserved =
1387 			flexcan_get_mb(priv, FLEXCAN_TX_MB_RESERVED_RX_MAILBOX);
1388 	else
1389 		priv->tx_mb_reserved =
1390 			flexcan_get_mb(priv, FLEXCAN_TX_MB_RESERVED_RX_FIFO);
1391 	priv->tx_mb_idx = priv->mb_count - 1;
1392 	priv->tx_mb = flexcan_get_mb(priv, priv->tx_mb_idx);
1393 	priv->tx_mask = FLEXCAN_IFLAG_MB(priv->tx_mb_idx);
1394 
1395 	priv->offload.mailbox_read = flexcan_mailbox_read;
1396 
1397 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX) {
1398 		priv->offload.mb_first = FLEXCAN_RX_MB_RX_MAILBOX_FIRST;
1399 		priv->offload.mb_last = priv->mb_count - 2;
1400 
1401 		priv->rx_mask = GENMASK_ULL(priv->offload.mb_last,
1402 					    priv->offload.mb_first);
1403 		err = can_rx_offload_add_timestamp(dev, &priv->offload);
1404 	} else {
1405 		priv->rx_mask = FLEXCAN_IFLAG_RX_FIFO_OVERFLOW |
1406 			FLEXCAN_IFLAG_RX_FIFO_AVAILABLE;
1407 		err = can_rx_offload_add_fifo(dev, &priv->offload,
1408 					      FLEXCAN_NAPI_WEIGHT);
1409 	}
1410 
1411 	return err;
1412 }
1413 
flexcan_chip_interrupts_enable(const struct net_device * dev)1414 static void flexcan_chip_interrupts_enable(const struct net_device *dev)
1415 {
1416 	const struct flexcan_priv *priv = netdev_priv(dev);
1417 	struct flexcan_regs __iomem *regs = priv->regs;
1418 	u64 reg_imask;
1419 
1420 	disable_irq(dev->irq);
1421 	priv->write(priv->reg_ctrl_default, &regs->ctrl);
1422 	reg_imask = priv->rx_mask | priv->tx_mask;
1423 	priv->write(upper_32_bits(reg_imask), &regs->imask2);
1424 	priv->write(lower_32_bits(reg_imask), &regs->imask1);
1425 	enable_irq(dev->irq);
1426 }
1427 
flexcan_chip_interrupts_disable(const struct net_device * dev)1428 static void flexcan_chip_interrupts_disable(const struct net_device *dev)
1429 {
1430 	const struct flexcan_priv *priv = netdev_priv(dev);
1431 	struct flexcan_regs __iomem *regs = priv->regs;
1432 
1433 	priv->write(0, &regs->imask2);
1434 	priv->write(0, &regs->imask1);
1435 	priv->write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL,
1436 		    &regs->ctrl);
1437 }
1438 
1439 /* flexcan_chip_start
1440  *
1441  * this functions is entered with clocks enabled
1442  *
1443  */
flexcan_chip_start(struct net_device * dev)1444 static int flexcan_chip_start(struct net_device *dev)
1445 {
1446 	struct flexcan_priv *priv = netdev_priv(dev);
1447 	struct flexcan_regs __iomem *regs = priv->regs;
1448 	u32 reg_mcr, reg_ctrl, reg_ctrl2, reg_mecr;
1449 	int err, i;
1450 	struct flexcan_mb __iomem *mb;
1451 
1452 	/* enable module */
1453 	err = flexcan_chip_enable(priv);
1454 	if (err)
1455 		return err;
1456 
1457 	/* soft reset */
1458 	err = flexcan_chip_softreset(priv);
1459 	if (err)
1460 		goto out_chip_disable;
1461 
1462 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SUPPORT_ECC)
1463 		flexcan_ram_init(dev);
1464 
1465 	flexcan_set_bittiming(dev);
1466 
1467 	/* set freeze, halt */
1468 	err = flexcan_chip_freeze(priv);
1469 	if (err)
1470 		goto out_chip_disable;
1471 
1472 	/* MCR
1473 	 *
1474 	 * only supervisor access
1475 	 * enable warning int
1476 	 * enable individual RX masking
1477 	 * choose format C
1478 	 * set max mailbox number
1479 	 */
1480 	reg_mcr = priv->read(&regs->mcr);
1481 	reg_mcr &= ~FLEXCAN_MCR_MAXMB(0xff);
1482 	reg_mcr |= FLEXCAN_MCR_SUPV | FLEXCAN_MCR_WRN_EN | FLEXCAN_MCR_IRMQ |
1483 		FLEXCAN_MCR_IDAM_C | FLEXCAN_MCR_MAXMB(priv->tx_mb_idx);
1484 
1485 	/* MCR
1486 	 *
1487 	 * FIFO:
1488 	 * - disable for mailbox mode
1489 	 * - enable for FIFO mode
1490 	 */
1491 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX)
1492 		reg_mcr &= ~FLEXCAN_MCR_FEN;
1493 	else
1494 		reg_mcr |= FLEXCAN_MCR_FEN;
1495 
1496 	/* MCR
1497 	 *
1498 	 * NOTE: In loopback mode, the CAN_MCR[SRXDIS] cannot be
1499 	 *       asserted because this will impede the self reception
1500 	 *       of a transmitted message. This is not documented in
1501 	 *       earlier versions of flexcan block guide.
1502 	 *
1503 	 * Self Reception:
1504 	 * - enable Self Reception for loopback mode
1505 	 *   (by clearing "Self Reception Disable" bit)
1506 	 * - disable for normal operation
1507 	 */
1508 	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
1509 		reg_mcr &= ~FLEXCAN_MCR_SRX_DIS;
1510 	else
1511 		reg_mcr |= FLEXCAN_MCR_SRX_DIS;
1512 
1513 	/* MCR - CAN-FD */
1514 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
1515 		reg_mcr |= FLEXCAN_MCR_FDEN;
1516 	else
1517 		reg_mcr &= ~FLEXCAN_MCR_FDEN;
1518 
1519 	netdev_dbg(dev, "%s: writing mcr=0x%08x", __func__, reg_mcr);
1520 	priv->write(reg_mcr, &regs->mcr);
1521 
1522 	/* CTRL
1523 	 *
1524 	 * disable timer sync feature
1525 	 *
1526 	 * disable auto busoff recovery
1527 	 * transmit lowest buffer first
1528 	 *
1529 	 * enable tx and rx warning interrupt
1530 	 * enable bus off interrupt
1531 	 * (== FLEXCAN_CTRL_ERR_STATE)
1532 	 */
1533 	reg_ctrl = priv->read(&regs->ctrl);
1534 	reg_ctrl &= ~FLEXCAN_CTRL_TSYN;
1535 	reg_ctrl |= FLEXCAN_CTRL_BOFF_REC | FLEXCAN_CTRL_LBUF |
1536 		FLEXCAN_CTRL_ERR_STATE;
1537 
1538 	/* enable the "error interrupt" (FLEXCAN_CTRL_ERR_MSK),
1539 	 * on most Flexcan cores, too. Otherwise we don't get
1540 	 * any error warning or passive interrupts.
1541 	 */
1542 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_BROKEN_WERR_STATE ||
1543 	    priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
1544 		reg_ctrl |= FLEXCAN_CTRL_ERR_MSK;
1545 	else
1546 		reg_ctrl &= ~FLEXCAN_CTRL_ERR_MSK;
1547 
1548 	/* save for later use */
1549 	priv->reg_ctrl_default = reg_ctrl;
1550 	/* leave interrupts disabled for now */
1551 	reg_ctrl &= ~FLEXCAN_CTRL_ERR_ALL;
1552 	netdev_dbg(dev, "%s: writing ctrl=0x%08x", __func__, reg_ctrl);
1553 	priv->write(reg_ctrl, &regs->ctrl);
1554 
1555 	if ((priv->devtype_data.quirks & FLEXCAN_QUIRK_ENABLE_EACEN_RRS)) {
1556 		reg_ctrl2 = priv->read(&regs->ctrl2);
1557 		reg_ctrl2 |= FLEXCAN_CTRL2_EACEN | FLEXCAN_CTRL2_RRS;
1558 		priv->write(reg_ctrl2, &regs->ctrl2);
1559 	}
1560 
1561 	if (priv->can.ctrlmode_supported & CAN_CTRLMODE_FD) {
1562 		u32 reg_fdctrl;
1563 
1564 		reg_fdctrl = priv->read(&regs->fdctrl);
1565 		reg_fdctrl &= ~(FIELD_PREP(FLEXCAN_FDCTRL_MBDSR1, 0x3) |
1566 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR0, 0x3));
1567 
1568 		if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
1569 			reg_fdctrl |=
1570 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR1,
1571 					   FLEXCAN_FDCTRL_MBDSR_64) |
1572 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR0,
1573 					   FLEXCAN_FDCTRL_MBDSR_64);
1574 		} else {
1575 			reg_fdctrl |=
1576 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR1,
1577 					   FLEXCAN_FDCTRL_MBDSR_8) |
1578 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR0,
1579 					   FLEXCAN_FDCTRL_MBDSR_8);
1580 		}
1581 
1582 		netdev_dbg(dev, "%s: writing fdctrl=0x%08x",
1583 			   __func__, reg_fdctrl);
1584 		priv->write(reg_fdctrl, &regs->fdctrl);
1585 	}
1586 
1587 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX) {
1588 		for (i = priv->offload.mb_first; i <= priv->offload.mb_last; i++) {
1589 			mb = flexcan_get_mb(priv, i);
1590 			priv->write(FLEXCAN_MB_CODE_RX_EMPTY,
1591 				    &mb->can_ctrl);
1592 		}
1593 	} else {
1594 		/* clear and invalidate unused mailboxes first */
1595 		for (i = FLEXCAN_TX_MB_RESERVED_RX_FIFO; i < priv->mb_count; i++) {
1596 			mb = flexcan_get_mb(priv, i);
1597 			priv->write(FLEXCAN_MB_CODE_RX_INACTIVE,
1598 				    &mb->can_ctrl);
1599 		}
1600 	}
1601 
1602 	/* Errata ERR005829: mark first TX mailbox as INACTIVE */
1603 	priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
1604 		    &priv->tx_mb_reserved->can_ctrl);
1605 
1606 	/* mark TX mailbox as INACTIVE */
1607 	priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
1608 		    &priv->tx_mb->can_ctrl);
1609 
1610 	/* acceptance mask/acceptance code (accept everything) */
1611 	priv->write(0x0, &regs->rxgmask);
1612 	priv->write(0x0, &regs->rx14mask);
1613 	priv->write(0x0, &regs->rx15mask);
1614 
1615 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_DISABLE_RXFG)
1616 		priv->write(0x0, &regs->rxfgmask);
1617 
1618 	/* clear acceptance filters */
1619 	for (i = 0; i < priv->mb_count; i++)
1620 		priv->write(0, &regs->rximr[i]);
1621 
1622 	/* On Vybrid, disable non-correctable errors interrupt and
1623 	 * freeze mode. It still can correct the correctable errors
1624 	 * when HW supports ECC.
1625 	 *
1626 	 * This also works around errata e5295 which generates false
1627 	 * positive memory errors and put the device in freeze mode.
1628 	 */
1629 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_DISABLE_MECR) {
1630 		/* Follow the protocol as described in "Detection
1631 		 * and Correction of Memory Errors" to write to
1632 		 * MECR register (step 1 - 5)
1633 		 *
1634 		 * 1. By default, CTRL2[ECRWRE] = 0, MECR[ECRWRDIS] = 1
1635 		 * 2. set CTRL2[ECRWRE]
1636 		 */
1637 		reg_ctrl2 = priv->read(&regs->ctrl2);
1638 		reg_ctrl2 |= FLEXCAN_CTRL2_ECRWRE;
1639 		priv->write(reg_ctrl2, &regs->ctrl2);
1640 
1641 		/* 3. clear MECR[ECRWRDIS] */
1642 		reg_mecr = priv->read(&regs->mecr);
1643 		reg_mecr &= ~FLEXCAN_MECR_ECRWRDIS;
1644 		priv->write(reg_mecr, &regs->mecr);
1645 
1646 		/* 4. all writes to MECR must keep MECR[ECRWRDIS] cleared */
1647 		reg_mecr &= ~(FLEXCAN_MECR_NCEFAFRZ | FLEXCAN_MECR_HANCEI_MSK |
1648 			      FLEXCAN_MECR_FANCEI_MSK);
1649 		priv->write(reg_mecr, &regs->mecr);
1650 
1651 		/* 5. after configuration done, lock MECR by either
1652 		 * setting MECR[ECRWRDIS] or clearing CTRL2[ECRWRE]
1653 		 */
1654 		reg_mecr |= FLEXCAN_MECR_ECRWRDIS;
1655 		priv->write(reg_mecr, &regs->mecr);
1656 
1657 		reg_ctrl2 &= ~FLEXCAN_CTRL2_ECRWRE;
1658 		priv->write(reg_ctrl2, &regs->ctrl2);
1659 	}
1660 
1661 	/* synchronize with the can bus */
1662 	err = flexcan_chip_unfreeze(priv);
1663 	if (err)
1664 		goto out_chip_disable;
1665 
1666 	priv->can.state = CAN_STATE_ERROR_ACTIVE;
1667 
1668 	/* print chip status */
1669 	netdev_dbg(dev, "%s: reading mcr=0x%08x ctrl=0x%08x\n", __func__,
1670 		   priv->read(&regs->mcr), priv->read(&regs->ctrl));
1671 
1672 	return 0;
1673 
1674  out_chip_disable:
1675 	flexcan_chip_disable(priv);
1676 	return err;
1677 }
1678 
1679 /* __flexcan_chip_stop
1680  *
1681  * this function is entered with clocks enabled
1682  */
__flexcan_chip_stop(struct net_device * dev,bool disable_on_error)1683 static int __flexcan_chip_stop(struct net_device *dev, bool disable_on_error)
1684 {
1685 	struct flexcan_priv *priv = netdev_priv(dev);
1686 	int err;
1687 
1688 	/* freeze + disable module */
1689 	err = flexcan_chip_freeze(priv);
1690 	if (err && !disable_on_error)
1691 		return err;
1692 	err = flexcan_chip_disable(priv);
1693 	if (err && !disable_on_error)
1694 		goto out_chip_unfreeze;
1695 
1696 	priv->can.state = CAN_STATE_STOPPED;
1697 
1698 	return 0;
1699 
1700  out_chip_unfreeze:
1701 	flexcan_chip_unfreeze(priv);
1702 
1703 	return err;
1704 }
1705 
flexcan_chip_stop_disable_on_error(struct net_device * dev)1706 static inline int flexcan_chip_stop_disable_on_error(struct net_device *dev)
1707 {
1708 	return __flexcan_chip_stop(dev, true);
1709 }
1710 
flexcan_chip_stop(struct net_device * dev)1711 static inline int flexcan_chip_stop(struct net_device *dev)
1712 {
1713 	return __flexcan_chip_stop(dev, false);
1714 }
1715 
flexcan_open(struct net_device * dev)1716 static int flexcan_open(struct net_device *dev)
1717 {
1718 	struct flexcan_priv *priv = netdev_priv(dev);
1719 	int err;
1720 
1721 	if ((priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) &&
1722 	    (priv->can.ctrlmode & CAN_CTRLMODE_FD)) {
1723 		netdev_err(dev, "Three Samples mode and CAN-FD mode can't be used together\n");
1724 		return -EINVAL;
1725 	}
1726 
1727 	err = pm_runtime_resume_and_get(priv->dev);
1728 	if (err < 0)
1729 		return err;
1730 
1731 	err = open_candev(dev);
1732 	if (err)
1733 		goto out_runtime_put;
1734 
1735 	err = flexcan_transceiver_enable(priv);
1736 	if (err)
1737 		goto out_close;
1738 
1739 	err = flexcan_rx_offload_setup(dev);
1740 	if (err)
1741 		goto out_transceiver_disable;
1742 
1743 	err = flexcan_chip_start(dev);
1744 	if (err)
1745 		goto out_can_rx_offload_del;
1746 
1747 	can_rx_offload_enable(&priv->offload);
1748 
1749 	err = request_irq(dev->irq, flexcan_irq, IRQF_SHARED, dev->name, dev);
1750 	if (err)
1751 		goto out_can_rx_offload_disable;
1752 
1753 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_NR_IRQ_3) {
1754 		err = request_irq(priv->irq_boff,
1755 				  flexcan_irq, IRQF_SHARED, dev->name, dev);
1756 		if (err)
1757 			goto out_free_irq;
1758 
1759 		err = request_irq(priv->irq_err,
1760 				  flexcan_irq, IRQF_SHARED, dev->name, dev);
1761 		if (err)
1762 			goto out_free_irq_boff;
1763 	}
1764 
1765 	flexcan_chip_interrupts_enable(dev);
1766 
1767 	netif_start_queue(dev);
1768 
1769 	return 0;
1770 
1771  out_free_irq_boff:
1772 	free_irq(priv->irq_boff, dev);
1773  out_free_irq:
1774 	free_irq(dev->irq, dev);
1775  out_can_rx_offload_disable:
1776 	can_rx_offload_disable(&priv->offload);
1777 	flexcan_chip_stop(dev);
1778  out_can_rx_offload_del:
1779 	can_rx_offload_del(&priv->offload);
1780  out_transceiver_disable:
1781 	flexcan_transceiver_disable(priv);
1782  out_close:
1783 	close_candev(dev);
1784  out_runtime_put:
1785 	pm_runtime_put(priv->dev);
1786 
1787 	return err;
1788 }
1789 
flexcan_close(struct net_device * dev)1790 static int flexcan_close(struct net_device *dev)
1791 {
1792 	struct flexcan_priv *priv = netdev_priv(dev);
1793 
1794 	netif_stop_queue(dev);
1795 	flexcan_chip_interrupts_disable(dev);
1796 
1797 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_NR_IRQ_3) {
1798 		free_irq(priv->irq_err, dev);
1799 		free_irq(priv->irq_boff, dev);
1800 	}
1801 
1802 	free_irq(dev->irq, dev);
1803 	can_rx_offload_disable(&priv->offload);
1804 	flexcan_chip_stop_disable_on_error(dev);
1805 
1806 	can_rx_offload_del(&priv->offload);
1807 	flexcan_transceiver_disable(priv);
1808 	close_candev(dev);
1809 
1810 	pm_runtime_put(priv->dev);
1811 
1812 	return 0;
1813 }
1814 
flexcan_set_mode(struct net_device * dev,enum can_mode mode)1815 static int flexcan_set_mode(struct net_device *dev, enum can_mode mode)
1816 {
1817 	int err;
1818 
1819 	switch (mode) {
1820 	case CAN_MODE_START:
1821 		err = flexcan_chip_start(dev);
1822 		if (err)
1823 			return err;
1824 
1825 		flexcan_chip_interrupts_enable(dev);
1826 
1827 		netif_wake_queue(dev);
1828 		break;
1829 
1830 	default:
1831 		return -EOPNOTSUPP;
1832 	}
1833 
1834 	return 0;
1835 }
1836 
1837 static const struct net_device_ops flexcan_netdev_ops = {
1838 	.ndo_open	= flexcan_open,
1839 	.ndo_stop	= flexcan_close,
1840 	.ndo_start_xmit	= flexcan_start_xmit,
1841 	.ndo_change_mtu = can_change_mtu,
1842 };
1843 
register_flexcandev(struct net_device * dev)1844 static int register_flexcandev(struct net_device *dev)
1845 {
1846 	struct flexcan_priv *priv = netdev_priv(dev);
1847 	struct flexcan_regs __iomem *regs = priv->regs;
1848 	u32 reg, err;
1849 
1850 	err = flexcan_clks_enable(priv);
1851 	if (err)
1852 		return err;
1853 
1854 	/* select "bus clock", chip must be disabled */
1855 	err = flexcan_chip_disable(priv);
1856 	if (err)
1857 		goto out_clks_disable;
1858 
1859 	reg = priv->read(&regs->ctrl);
1860 	if (priv->clk_src)
1861 		reg |= FLEXCAN_CTRL_CLK_SRC;
1862 	else
1863 		reg &= ~FLEXCAN_CTRL_CLK_SRC;
1864 	priv->write(reg, &regs->ctrl);
1865 
1866 	err = flexcan_chip_enable(priv);
1867 	if (err)
1868 		goto out_chip_disable;
1869 
1870 	/* set freeze, halt */
1871 	err = flexcan_chip_freeze(priv);
1872 	if (err)
1873 		goto out_chip_disable;
1874 
1875 	/* activate FIFO, restrict register access */
1876 	reg = priv->read(&regs->mcr);
1877 	reg |=  FLEXCAN_MCR_FEN | FLEXCAN_MCR_SUPV;
1878 	priv->write(reg, &regs->mcr);
1879 
1880 	/* Currently we only support newer versions of this core
1881 	 * featuring a RX hardware FIFO (although this driver doesn't
1882 	 * make use of it on some cores). Older cores, found on some
1883 	 * Coldfire derivates are not tested.
1884 	 */
1885 	reg = priv->read(&regs->mcr);
1886 	if (!(reg & FLEXCAN_MCR_FEN)) {
1887 		netdev_err(dev, "Could not enable RX FIFO, unsupported core\n");
1888 		err = -ENODEV;
1889 		goto out_chip_disable;
1890 	}
1891 
1892 	err = register_candev(dev);
1893 	if (err)
1894 		goto out_chip_disable;
1895 
1896 	/* Disable core and let pm_runtime_put() disable the clocks.
1897 	 * If CONFIG_PM is not enabled, the clocks will stay powered.
1898 	 */
1899 	flexcan_chip_disable(priv);
1900 	pm_runtime_put(priv->dev);
1901 
1902 	return 0;
1903 
1904  out_chip_disable:
1905 	flexcan_chip_disable(priv);
1906  out_clks_disable:
1907 	flexcan_clks_disable(priv);
1908 	return err;
1909 }
1910 
unregister_flexcandev(struct net_device * dev)1911 static void unregister_flexcandev(struct net_device *dev)
1912 {
1913 	unregister_candev(dev);
1914 }
1915 
flexcan_setup_stop_mode_gpr(struct platform_device * pdev)1916 static int flexcan_setup_stop_mode_gpr(struct platform_device *pdev)
1917 {
1918 	struct net_device *dev = platform_get_drvdata(pdev);
1919 	struct device_node *np = pdev->dev.of_node;
1920 	struct device_node *gpr_np;
1921 	struct flexcan_priv *priv;
1922 	phandle phandle;
1923 	u32 out_val[3];
1924 	int ret;
1925 
1926 	if (!np)
1927 		return -EINVAL;
1928 
1929 	/* stop mode property format is:
1930 	 * <&gpr req_gpr req_bit>.
1931 	 */
1932 	ret = of_property_read_u32_array(np, "fsl,stop-mode", out_val,
1933 					 ARRAY_SIZE(out_val));
1934 	if (ret) {
1935 		dev_dbg(&pdev->dev, "no stop-mode property\n");
1936 		return ret;
1937 	}
1938 	phandle = *out_val;
1939 
1940 	gpr_np = of_find_node_by_phandle(phandle);
1941 	if (!gpr_np) {
1942 		dev_dbg(&pdev->dev, "could not find gpr node by phandle\n");
1943 		return -ENODEV;
1944 	}
1945 
1946 	priv = netdev_priv(dev);
1947 	priv->stm.gpr = syscon_node_to_regmap(gpr_np);
1948 	if (IS_ERR(priv->stm.gpr)) {
1949 		dev_dbg(&pdev->dev, "could not find gpr regmap\n");
1950 		ret = PTR_ERR(priv->stm.gpr);
1951 		goto out_put_node;
1952 	}
1953 
1954 	priv->stm.req_gpr = out_val[1];
1955 	priv->stm.req_bit = out_val[2];
1956 
1957 	dev_dbg(&pdev->dev,
1958 		"gpr %s req_gpr=0x02%x req_bit=%u\n",
1959 		gpr_np->full_name, priv->stm.req_gpr, priv->stm.req_bit);
1960 
1961 	return 0;
1962 
1963 out_put_node:
1964 	of_node_put(gpr_np);
1965 	return ret;
1966 }
1967 
flexcan_setup_stop_mode_scfw(struct platform_device * pdev)1968 static int flexcan_setup_stop_mode_scfw(struct platform_device *pdev)
1969 {
1970 	struct net_device *dev = platform_get_drvdata(pdev);
1971 	struct flexcan_priv *priv;
1972 	u8 scu_idx;
1973 	int ret;
1974 
1975 	ret = of_property_read_u8(pdev->dev.of_node, "fsl,scu-index", &scu_idx);
1976 	if (ret < 0) {
1977 		dev_dbg(&pdev->dev, "failed to get scu index\n");
1978 		return ret;
1979 	}
1980 
1981 	priv = netdev_priv(dev);
1982 	priv->scu_idx = scu_idx;
1983 
1984 	/* this function could be deferred probe, return -EPROBE_DEFER */
1985 	return imx_scu_get_handle(&priv->sc_ipc_handle);
1986 }
1987 
1988 /* flexcan_setup_stop_mode - Setup stop mode for wakeup
1989  *
1990  * Return: = 0 setup stop mode successfully or doesn't support this feature
1991  *         < 0 fail to setup stop mode (could be deferred probe)
1992  */
flexcan_setup_stop_mode(struct platform_device * pdev)1993 static int flexcan_setup_stop_mode(struct platform_device *pdev)
1994 {
1995 	struct net_device *dev = platform_get_drvdata(pdev);
1996 	struct flexcan_priv *priv;
1997 	int ret;
1998 
1999 	priv = netdev_priv(dev);
2000 
2001 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW)
2002 		ret = flexcan_setup_stop_mode_scfw(pdev);
2003 	else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR)
2004 		ret = flexcan_setup_stop_mode_gpr(pdev);
2005 	else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI)
2006 		/* ATF will handle all STOP_IPG related work */
2007 		ret = 0;
2008 	else
2009 		/* return 0 directly if doesn't support stop mode feature */
2010 		return 0;
2011 
2012 	/* If ret is -EINVAL, this means SoC claim to support stop mode, but
2013 	 * dts file lack the stop mode property definition. For this case,
2014 	 * directly return 0, this will skip the wakeup capable setting and
2015 	 * will not block the driver probe.
2016 	 */
2017 	if (ret == -EINVAL)
2018 		return 0;
2019 	else if (ret)
2020 		return ret;
2021 
2022 	device_set_wakeup_capable(&pdev->dev, true);
2023 
2024 	if (of_property_read_bool(pdev->dev.of_node, "wakeup-source"))
2025 		device_set_wakeup_enable(&pdev->dev, true);
2026 
2027 	return 0;
2028 }
2029 
2030 static const struct of_device_id flexcan_of_match[] = {
2031 	{ .compatible = "fsl,imx8qm-flexcan", .data = &fsl_imx8qm_devtype_data, },
2032 	{ .compatible = "fsl,imx8mp-flexcan", .data = &fsl_imx8mp_devtype_data, },
2033 	{ .compatible = "fsl,imx93-flexcan", .data = &fsl_imx93_devtype_data, },
2034 	{ .compatible = "fsl,imx95-flexcan", .data = &fsl_imx95_devtype_data, },
2035 	{ .compatible = "fsl,imx6q-flexcan", .data = &fsl_imx6q_devtype_data, },
2036 	{ .compatible = "fsl,imx28-flexcan", .data = &fsl_imx28_devtype_data, },
2037 	{ .compatible = "fsl,imx53-flexcan", .data = &fsl_imx25_devtype_data, },
2038 	{ .compatible = "fsl,imx35-flexcan", .data = &fsl_imx25_devtype_data, },
2039 	{ .compatible = "fsl,imx25-flexcan", .data = &fsl_imx25_devtype_data, },
2040 	{ .compatible = "fsl,p1010-flexcan", .data = &fsl_p1010_devtype_data, },
2041 	{ .compatible = "fsl,vf610-flexcan", .data = &fsl_vf610_devtype_data, },
2042 	{ .compatible = "fsl,ls1021ar2-flexcan", .data = &fsl_ls1021a_r2_devtype_data, },
2043 	{ .compatible = "fsl,lx2160ar1-flexcan", .data = &fsl_lx2160a_r1_devtype_data, },
2044 	{ /* sentinel */ },
2045 };
2046 MODULE_DEVICE_TABLE(of, flexcan_of_match);
2047 
2048 static const struct platform_device_id flexcan_id_table[] = {
2049 	{
2050 		.name = "flexcan-mcf5441x",
2051 		.driver_data = (kernel_ulong_t)&fsl_mcf5441x_devtype_data,
2052 	}, {
2053 		/* sentinel */
2054 	},
2055 };
2056 MODULE_DEVICE_TABLE(platform, flexcan_id_table);
2057 
flexcan_probe(struct platform_device * pdev)2058 static int flexcan_probe(struct platform_device *pdev)
2059 {
2060 	const struct flexcan_devtype_data *devtype_data;
2061 	struct net_device *dev;
2062 	struct flexcan_priv *priv;
2063 	struct regulator *reg_xceiver;
2064 	struct clk *clk_ipg = NULL, *clk_per = NULL;
2065 	struct flexcan_regs __iomem *regs;
2066 	struct flexcan_platform_data *pdata;
2067 	int err, irq;
2068 	u8 clk_src = 1;
2069 	u32 clock_freq = 0;
2070 
2071 	reg_xceiver = devm_regulator_get_optional(&pdev->dev, "xceiver");
2072 	if (PTR_ERR(reg_xceiver) == -EPROBE_DEFER)
2073 		return -EPROBE_DEFER;
2074 	else if (PTR_ERR(reg_xceiver) == -ENODEV)
2075 		reg_xceiver = NULL;
2076 	else if (IS_ERR(reg_xceiver))
2077 		return PTR_ERR(reg_xceiver);
2078 
2079 	if (pdev->dev.of_node) {
2080 		of_property_read_u32(pdev->dev.of_node,
2081 				     "clock-frequency", &clock_freq);
2082 		of_property_read_u8(pdev->dev.of_node,
2083 				    "fsl,clk-source", &clk_src);
2084 	} else {
2085 		pdata = dev_get_platdata(&pdev->dev);
2086 		if (pdata) {
2087 			clock_freq = pdata->clock_frequency;
2088 			clk_src = pdata->clk_src;
2089 		}
2090 	}
2091 
2092 	if (!clock_freq) {
2093 		clk_ipg = devm_clk_get(&pdev->dev, "ipg");
2094 		if (IS_ERR(clk_ipg)) {
2095 			dev_err(&pdev->dev, "no ipg clock defined\n");
2096 			return PTR_ERR(clk_ipg);
2097 		}
2098 
2099 		clk_per = devm_clk_get(&pdev->dev, "per");
2100 		if (IS_ERR(clk_per)) {
2101 			dev_err(&pdev->dev, "no per clock defined\n");
2102 			return PTR_ERR(clk_per);
2103 		}
2104 		clock_freq = clk_get_rate(clk_per);
2105 	}
2106 
2107 	irq = platform_get_irq(pdev, 0);
2108 	if (irq < 0)
2109 		return irq;
2110 
2111 	regs = devm_platform_ioremap_resource(pdev, 0);
2112 	if (IS_ERR(regs))
2113 		return PTR_ERR(regs);
2114 
2115 	devtype_data = device_get_match_data(&pdev->dev);
2116 
2117 	if ((devtype_data->quirks & FLEXCAN_QUIRK_SUPPORT_FD) &&
2118 	    !((devtype_data->quirks &
2119 	       (FLEXCAN_QUIRK_USE_RX_MAILBOX |
2120 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
2121 		FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR |
2122 		FLEXCAN_QUIRK_SUPPORT_RX_FIFO)) ==
2123 	      (FLEXCAN_QUIRK_USE_RX_MAILBOX |
2124 	       FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
2125 	       FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR))) {
2126 		dev_err(&pdev->dev, "CAN-FD mode doesn't work in RX-FIFO mode!\n");
2127 		return -EINVAL;
2128 	}
2129 
2130 	if ((devtype_data->quirks &
2131 	     (FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX |
2132 	      FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR)) ==
2133 	    FLEXCAN_QUIRK_SUPPORT_RX_MAILBOX_RTR) {
2134 		dev_err(&pdev->dev,
2135 			"Quirks (0x%08x) inconsistent: RX_MAILBOX_RX supported but not RX_MAILBOX\n",
2136 			devtype_data->quirks);
2137 		return -EINVAL;
2138 	}
2139 
2140 	dev = alloc_candev(sizeof(struct flexcan_priv), 1);
2141 	if (!dev)
2142 		return -ENOMEM;
2143 
2144 	platform_set_drvdata(pdev, dev);
2145 	SET_NETDEV_DEV(dev, &pdev->dev);
2146 
2147 	dev->netdev_ops = &flexcan_netdev_ops;
2148 	dev->ethtool_ops = &flexcan_ethtool_ops;
2149 	dev->irq = irq;
2150 	dev->flags |= IFF_ECHO;
2151 
2152 	priv = netdev_priv(dev);
2153 	priv->devtype_data = *devtype_data;
2154 
2155 	if (of_property_read_bool(pdev->dev.of_node, "big-endian") ||
2156 	    priv->devtype_data.quirks & FLEXCAN_QUIRK_DEFAULT_BIG_ENDIAN) {
2157 		priv->read = flexcan_read_be;
2158 		priv->write = flexcan_write_be;
2159 	} else {
2160 		priv->read = flexcan_read_le;
2161 		priv->write = flexcan_write_le;
2162 	}
2163 
2164 	priv->dev = &pdev->dev;
2165 	priv->can.clock.freq = clock_freq;
2166 	priv->can.do_set_mode = flexcan_set_mode;
2167 	priv->can.do_get_berr_counter = flexcan_get_berr_counter;
2168 	priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
2169 		CAN_CTRLMODE_LISTENONLY	| CAN_CTRLMODE_3_SAMPLES |
2170 		CAN_CTRLMODE_BERR_REPORTING;
2171 	priv->regs = regs;
2172 	priv->clk_ipg = clk_ipg;
2173 	priv->clk_per = clk_per;
2174 	priv->clk_src = clk_src;
2175 	priv->reg_xceiver = reg_xceiver;
2176 
2177 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_NR_IRQ_3) {
2178 		priv->irq_boff = platform_get_irq(pdev, 1);
2179 		if (priv->irq_boff < 0) {
2180 			err = priv->irq_boff;
2181 			goto failed_platform_get_irq;
2182 		}
2183 		priv->irq_err = platform_get_irq(pdev, 2);
2184 		if (priv->irq_err < 0) {
2185 			err = priv->irq_err;
2186 			goto failed_platform_get_irq;
2187 		}
2188 	}
2189 
2190 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SUPPORT_FD) {
2191 		priv->can.ctrlmode_supported |= CAN_CTRLMODE_FD |
2192 			CAN_CTRLMODE_FD_NON_ISO;
2193 		priv->can.bittiming_const = &flexcan_fd_bittiming_const;
2194 		priv->can.data_bittiming_const =
2195 			&flexcan_fd_data_bittiming_const;
2196 	} else {
2197 		priv->can.bittiming_const = &flexcan_bittiming_const;
2198 	}
2199 
2200 	pm_runtime_get_noresume(&pdev->dev);
2201 	pm_runtime_set_active(&pdev->dev);
2202 	pm_runtime_enable(&pdev->dev);
2203 
2204 	err = register_flexcandev(dev);
2205 	if (err) {
2206 		dev_err(&pdev->dev, "registering netdev failed\n");
2207 		goto failed_register;
2208 	}
2209 
2210 	err = flexcan_setup_stop_mode(pdev);
2211 	if (err < 0) {
2212 		dev_err_probe(&pdev->dev, err, "setup stop mode failed\n");
2213 		goto failed_setup_stop_mode;
2214 	}
2215 
2216 	of_can_transceiver(dev);
2217 
2218 	return 0;
2219 
2220  failed_setup_stop_mode:
2221 	unregister_flexcandev(dev);
2222  failed_register:
2223 	pm_runtime_put_noidle(&pdev->dev);
2224 	pm_runtime_disable(&pdev->dev);
2225  failed_platform_get_irq:
2226 	free_candev(dev);
2227 	return err;
2228 }
2229 
flexcan_remove(struct platform_device * pdev)2230 static void flexcan_remove(struct platform_device *pdev)
2231 {
2232 	struct net_device *dev = platform_get_drvdata(pdev);
2233 
2234 	device_set_wakeup_enable(&pdev->dev, false);
2235 	device_set_wakeup_capable(&pdev->dev, false);
2236 	unregister_flexcandev(dev);
2237 	pm_runtime_disable(&pdev->dev);
2238 	free_candev(dev);
2239 }
2240 
flexcan_suspend(struct device * device)2241 static int __maybe_unused flexcan_suspend(struct device *device)
2242 {
2243 	struct net_device *dev = dev_get_drvdata(device);
2244 	struct flexcan_priv *priv = netdev_priv(dev);
2245 	int err;
2246 
2247 	if (netif_running(dev)) {
2248 		/* if wakeup is enabled, enter stop mode
2249 		 * else enter disabled mode.
2250 		 */
2251 		if (device_may_wakeup(device)) {
2252 			enable_irq_wake(dev->irq);
2253 			err = flexcan_enter_stop_mode(priv);
2254 			if (err)
2255 				return err;
2256 		} else {
2257 			err = flexcan_chip_stop(dev);
2258 			if (err)
2259 				return err;
2260 
2261 			flexcan_chip_interrupts_disable(dev);
2262 
2263 			err = pinctrl_pm_select_sleep_state(device);
2264 			if (err)
2265 				return err;
2266 		}
2267 		netif_stop_queue(dev);
2268 		netif_device_detach(dev);
2269 	}
2270 	priv->can.state = CAN_STATE_SLEEPING;
2271 
2272 	return 0;
2273 }
2274 
flexcan_resume(struct device * device)2275 static int __maybe_unused flexcan_resume(struct device *device)
2276 {
2277 	struct net_device *dev = dev_get_drvdata(device);
2278 	struct flexcan_priv *priv = netdev_priv(dev);
2279 	int err;
2280 
2281 	priv->can.state = CAN_STATE_ERROR_ACTIVE;
2282 	if (netif_running(dev)) {
2283 		netif_device_attach(dev);
2284 		netif_start_queue(dev);
2285 		if (device_may_wakeup(device)) {
2286 			disable_irq_wake(dev->irq);
2287 			err = flexcan_exit_stop_mode(priv);
2288 			if (err)
2289 				return err;
2290 		} else {
2291 			err = pinctrl_pm_select_default_state(device);
2292 			if (err)
2293 				return err;
2294 
2295 			err = flexcan_chip_start(dev);
2296 			if (err)
2297 				return err;
2298 
2299 			flexcan_chip_interrupts_enable(dev);
2300 		}
2301 	}
2302 
2303 	return 0;
2304 }
2305 
flexcan_runtime_suspend(struct device * device)2306 static int __maybe_unused flexcan_runtime_suspend(struct device *device)
2307 {
2308 	struct net_device *dev = dev_get_drvdata(device);
2309 	struct flexcan_priv *priv = netdev_priv(dev);
2310 
2311 	flexcan_clks_disable(priv);
2312 
2313 	return 0;
2314 }
2315 
flexcan_runtime_resume(struct device * device)2316 static int __maybe_unused flexcan_runtime_resume(struct device *device)
2317 {
2318 	struct net_device *dev = dev_get_drvdata(device);
2319 	struct flexcan_priv *priv = netdev_priv(dev);
2320 
2321 	return flexcan_clks_enable(priv);
2322 }
2323 
flexcan_noirq_suspend(struct device * device)2324 static int __maybe_unused flexcan_noirq_suspend(struct device *device)
2325 {
2326 	struct net_device *dev = dev_get_drvdata(device);
2327 	struct flexcan_priv *priv = netdev_priv(dev);
2328 
2329 	if (netif_running(dev)) {
2330 		int err;
2331 
2332 		if (device_may_wakeup(device))
2333 			flexcan_enable_wakeup_irq(priv, true);
2334 
2335 		/* For FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI, it need ATF to send
2336 		 * to SM through SCMI protocol, SM will assert the IPG_STOP
2337 		 * signal. But all this works need the CAN clocks keep on.
2338 		 * After the CAN module get the IPG_STOP mode, and switch to
2339 		 * STOP mode, whether still keep the CAN clocks on or gate them
2340 		 * off depend on the Hardware design.
2341 		 */
2342 		if (!(device_may_wakeup(device) &&
2343 		      priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI)) {
2344 			err = pm_runtime_force_suspend(device);
2345 			if (err)
2346 				return err;
2347 		}
2348 	}
2349 
2350 	return 0;
2351 }
2352 
flexcan_noirq_resume(struct device * device)2353 static int __maybe_unused flexcan_noirq_resume(struct device *device)
2354 {
2355 	struct net_device *dev = dev_get_drvdata(device);
2356 	struct flexcan_priv *priv = netdev_priv(dev);
2357 
2358 	if (netif_running(dev)) {
2359 		int err;
2360 
2361 		if (!(device_may_wakeup(device) &&
2362 		      priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCMI)) {
2363 			err = pm_runtime_force_resume(device);
2364 			if (err)
2365 				return err;
2366 		}
2367 
2368 		if (device_may_wakeup(device))
2369 			flexcan_enable_wakeup_irq(priv, false);
2370 	}
2371 
2372 	return 0;
2373 }
2374 
2375 static const struct dev_pm_ops flexcan_pm_ops = {
2376 	SET_SYSTEM_SLEEP_PM_OPS(flexcan_suspend, flexcan_resume)
2377 	SET_RUNTIME_PM_OPS(flexcan_runtime_suspend, flexcan_runtime_resume, NULL)
2378 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(flexcan_noirq_suspend, flexcan_noirq_resume)
2379 };
2380 
2381 static struct platform_driver flexcan_driver = {
2382 	.driver = {
2383 		.name = DRV_NAME,
2384 		.pm = &flexcan_pm_ops,
2385 		.of_match_table = flexcan_of_match,
2386 	},
2387 	.probe = flexcan_probe,
2388 	.remove = flexcan_remove,
2389 	.id_table = flexcan_id_table,
2390 };
2391 
2392 module_platform_driver(flexcan_driver);
2393 
2394 MODULE_AUTHOR("Sascha Hauer <kernel@pengutronix.de>, "
2395 	      "Marc Kleine-Budde <kernel@pengutronix.de>");
2396 MODULE_LICENSE("GPL v2");
2397 MODULE_DESCRIPTION("CAN port driver for flexcan based chip");
2398