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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/can/led.h>
18 #include <linux/can/rx-offload.h>
19 #include <linux/clk.h>
20 #include <linux/delay.h>
21 #include <linux/firmware/imx/sci.h>
22 #include <linux/interrupt.h>
23 #include <linux/io.h>
24 #include <linux/mfd/syscon.h>
25 #include <linux/module.h>
26 #include <linux/netdevice.h>
27 #include <linux/of.h>
28 #include <linux/of_device.h>
29 #include <linux/pinctrl/consumer.h>
30 #include <linux/platform_device.h>
31 #include <linux/can/platform/flexcan.h>
32 #include <linux/pm_runtime.h>
33 #include <linux/regmap.h>
34 #include <linux/regulator/consumer.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 /* FLEXCAN hardware feature flags
210  *
211  * Below is some version info we got:
212  *    SOC   Version   IP-Version  Glitch- [TR]WRN_INT IRQ Err Memory err RTR rece-   FD Mode     MB
213  *                                Filter? connected?  Passive detection  ption in MB Supported?
214  * MCF5441X FlexCAN2  ?               no       yes        no       no       yes           no     16
215  *    MX25  FlexCAN2  03.00.00.00     no        no        no       no        no           no     64
216  *    MX28  FlexCAN2  03.00.04.00    yes       yes        no       no        no           no     64
217  *    MX35  FlexCAN2  03.00.00.00     no        no        no       no        no           no     64
218  *    MX53  FlexCAN2  03.00.00.00    yes        no        no       no        no           no     64
219  *    MX6s  FlexCAN3  10.00.12.00    yes       yes        no       no       yes           no     64
220  *    MX8QM FlexCAN3  03.00.23.00    yes       yes        no       no       yes          yes     64
221  *    MX8MP FlexCAN3  03.00.17.01    yes       yes        no      yes       yes          yes     64
222  *    VF610 FlexCAN3  ?               no       yes        no      yes       yes?          no     64
223  *  LS1021A FlexCAN2  03.00.04.00     no       yes        no       no       yes           no     64
224  *  LX2160A FlexCAN3  03.00.23.00     no       yes        no      yes       yes          yes     64
225  *
226  * Some SOCs do not have the RX_WARN & TX_WARN interrupt line connected.
227  */
228 
229 /* [TR]WRN_INT not connected */
230 #define FLEXCAN_QUIRK_BROKEN_WERR_STATE BIT(1)
231  /* Disable RX FIFO Global mask */
232 #define FLEXCAN_QUIRK_DISABLE_RXFG BIT(2)
233 /* Enable EACEN and RRS bit in ctrl2 */
234 #define FLEXCAN_QUIRK_ENABLE_EACEN_RRS  BIT(3)
235 /* Disable non-correctable errors interrupt and freeze mode */
236 #define FLEXCAN_QUIRK_DISABLE_MECR BIT(4)
237 /* Use mailboxes (not FIFO) for RX path */
238 #define FLEXCAN_QUIRK_USE_RX_MAILBOX BIT(5)
239 /* No interrupt for error passive */
240 #define FLEXCAN_QUIRK_BROKEN_PERR_STATE BIT(6)
241 /* default to BE register access */
242 #define FLEXCAN_QUIRK_DEFAULT_BIG_ENDIAN BIT(7)
243 /* Setup stop mode with GPR to support wakeup */
244 #define FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR BIT(8)
245 /* Support CAN-FD mode */
246 #define FLEXCAN_QUIRK_SUPPORT_FD BIT(9)
247 /* support memory detection and correction */
248 #define FLEXCAN_QUIRK_SUPPORT_ECC BIT(10)
249 /* Setup stop mode with SCU firmware to support wakeup */
250 #define FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW BIT(11)
251 /* Setup 3 separate interrupts, main, boff and err */
252 #define FLEXCAN_QUIRK_NR_IRQ_3 BIT(12)
253 /* Setup 16 mailboxes */
254 #define FLEXCAN_QUIRK_NR_MB_16 BIT(13)
255 /* Device supports RX via mailboxes */
256 #define FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX BIT(14)
257 /* Device supports RTR reception via mailboxes */
258 #define FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX_RTR BIT(15)
259 /* Device supports RX via FIFO */
260 #define FLEXCAN_QUIRK_SUPPPORT_RX_FIFO BIT(16)
261 
262 /* Structure of the message buffer */
263 struct flexcan_mb {
264 	u32 can_ctrl;
265 	u32 can_id;
266 	u32 data[];
267 };
268 
269 /* Structure of the hardware registers */
270 struct flexcan_regs {
271 	u32 mcr;		/* 0x00 */
272 	u32 ctrl;		/* 0x04 - Not affected by Soft Reset */
273 	u32 timer;		/* 0x08 */
274 	u32 tcr;		/* 0x0c */
275 	u32 rxgmask;		/* 0x10 - Not affected by Soft Reset */
276 	u32 rx14mask;		/* 0x14 - Not affected by Soft Reset */
277 	u32 rx15mask;		/* 0x18 - Not affected by Soft Reset */
278 	u32 ecr;		/* 0x1c */
279 	u32 esr;		/* 0x20 */
280 	u32 imask2;		/* 0x24 */
281 	u32 imask1;		/* 0x28 */
282 	u32 iflag2;		/* 0x2c */
283 	u32 iflag1;		/* 0x30 */
284 	union {			/* 0x34 */
285 		u32 gfwr_mx28;	/* MX28, MX53 */
286 		u32 ctrl2;	/* MX6, VF610 - Not affected by Soft Reset */
287 	};
288 	u32 esr2;		/* 0x38 */
289 	u32 imeur;		/* 0x3c */
290 	u32 lrfr;		/* 0x40 */
291 	u32 crcr;		/* 0x44 */
292 	u32 rxfgmask;		/* 0x48 */
293 	u32 rxfir;		/* 0x4c - Not affected by Soft Reset */
294 	u32 cbt;		/* 0x50 - Not affected by Soft Reset */
295 	u32 _reserved2;		/* 0x54 */
296 	u32 dbg1;		/* 0x58 */
297 	u32 dbg2;		/* 0x5c */
298 	u32 _reserved3[8];	/* 0x60 */
299 	u8 mb[2][512];		/* 0x80 - Not affected by Soft Reset */
300 	/* FIFO-mode:
301 	 *			MB
302 	 * 0x080...0x08f	0	RX message buffer
303 	 * 0x090...0x0df	1-5	reserved
304 	 * 0x0e0...0x0ff	6-7	8 entry ID table
305 	 *				(mx25, mx28, mx35, mx53)
306 	 * 0x0e0...0x2df	6-7..37	8..128 entry ID table
307 	 *				size conf'ed via ctrl2::RFFN
308 	 *				(mx6, vf610)
309 	 */
310 	u32 _reserved4[256];	/* 0x480 */
311 	u32 rximr[64];		/* 0x880 - Not affected by Soft Reset */
312 	u32 _reserved5[24];	/* 0x980 */
313 	u32 gfwr_mx6;		/* 0x9e0 - MX6 */
314 	u32 _reserved6[39];	/* 0x9e4 */
315 	u32 _rxfir[6];		/* 0xa80 */
316 	u32 _reserved8[2];	/* 0xa98 */
317 	u32 _rxmgmask;		/* 0xaa0 */
318 	u32 _rxfgmask;		/* 0xaa4 */
319 	u32 _rx14mask;		/* 0xaa8 */
320 	u32 _rx15mask;		/* 0xaac */
321 	u32 tx_smb[4];		/* 0xab0 */
322 	u32 rx_smb0[4];		/* 0xac0 */
323 	u32 rx_smb1[4];		/* 0xad0 */
324 	u32 mecr;		/* 0xae0 */
325 	u32 erriar;		/* 0xae4 */
326 	u32 erridpr;		/* 0xae8 */
327 	u32 errippr;		/* 0xaec */
328 	u32 rerrar;		/* 0xaf0 */
329 	u32 rerrdr;		/* 0xaf4 */
330 	u32 rerrsynr;		/* 0xaf8 */
331 	u32 errsr;		/* 0xafc */
332 	u32 _reserved7[64];	/* 0xb00 */
333 	u32 fdctrl;		/* 0xc00 - Not affected by Soft Reset */
334 	u32 fdcbt;		/* 0xc04 - Not affected by Soft Reset */
335 	u32 fdcrc;		/* 0xc08 */
336 	u32 _reserved9[199];	/* 0xc0c */
337 	u32 tx_smb_fd[18];	/* 0xf28 */
338 	u32 rx_smb0_fd[18];	/* 0xf70 */
339 	u32 rx_smb1_fd[18];	/* 0xfb8 */
340 };
341 
342 static_assert(sizeof(struct flexcan_regs) ==  0x4 * 18 + 0xfb8);
343 
344 struct flexcan_devtype_data {
345 	u32 quirks;		/* quirks needed for different IP cores */
346 };
347 
348 struct flexcan_stop_mode {
349 	struct regmap *gpr;
350 	u8 req_gpr;
351 	u8 req_bit;
352 };
353 
354 struct flexcan_priv {
355 	struct can_priv can;
356 	struct can_rx_offload offload;
357 	struct device *dev;
358 
359 	struct flexcan_regs __iomem *regs;
360 	struct flexcan_mb __iomem *tx_mb;
361 	struct flexcan_mb __iomem *tx_mb_reserved;
362 	u8 tx_mb_idx;
363 	u8 mb_count;
364 	u8 mb_size;
365 	u8 clk_src;	/* clock source of CAN Protocol Engine */
366 	u8 scu_idx;
367 
368 	u64 rx_mask;
369 	u64 tx_mask;
370 	u32 reg_ctrl_default;
371 
372 	struct clk *clk_ipg;
373 	struct clk *clk_per;
374 	struct flexcan_devtype_data devtype_data;
375 	struct regulator *reg_xceiver;
376 	struct flexcan_stop_mode stm;
377 
378 	int irq_boff;
379 	int irq_err;
380 
381 	/* IPC handle when setup stop mode by System Controller firmware(scfw) */
382 	struct imx_sc_ipc *sc_ipc_handle;
383 
384 	/* Read and Write APIs */
385 	u32 (*read)(void __iomem *addr);
386 	void (*write)(u32 val, void __iomem *addr);
387 };
388 
389 static const struct flexcan_devtype_data fsl_mcf5441x_devtype_data = {
390 	.quirks = FLEXCAN_QUIRK_BROKEN_PERR_STATE |
391 		FLEXCAN_QUIRK_NR_IRQ_3 | FLEXCAN_QUIRK_NR_MB_16 |
392 		FLEXCAN_QUIRK_SUPPPORT_RX_FIFO,
393 };
394 
395 static const struct flexcan_devtype_data fsl_p1010_devtype_data = {
396 	.quirks = FLEXCAN_QUIRK_BROKEN_WERR_STATE |
397 		FLEXCAN_QUIRK_BROKEN_PERR_STATE |
398 		FLEXCAN_QUIRK_DEFAULT_BIG_ENDIAN |
399 		FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX |
400 		FLEXCAN_QUIRK_SUPPPORT_RX_FIFO,
401 };
402 
403 static const struct flexcan_devtype_data fsl_imx25_devtype_data = {
404 	.quirks = FLEXCAN_QUIRK_BROKEN_WERR_STATE |
405 		FLEXCAN_QUIRK_BROKEN_PERR_STATE |
406 		FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX |
407 		FLEXCAN_QUIRK_SUPPPORT_RX_FIFO,
408 };
409 
410 static const struct flexcan_devtype_data fsl_imx28_devtype_data = {
411 	.quirks = FLEXCAN_QUIRK_BROKEN_PERR_STATE |
412 		FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX |
413 		FLEXCAN_QUIRK_SUPPPORT_RX_FIFO,
414 };
415 
416 static const struct flexcan_devtype_data fsl_imx6q_devtype_data = {
417 	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
418 		FLEXCAN_QUIRK_USE_RX_MAILBOX | FLEXCAN_QUIRK_BROKEN_PERR_STATE |
419 		FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR |
420 		FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX |
421 		FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX_RTR,
422 };
423 
424 static const struct flexcan_devtype_data fsl_imx8qm_devtype_data = {
425 	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
426 		FLEXCAN_QUIRK_USE_RX_MAILBOX | FLEXCAN_QUIRK_BROKEN_PERR_STATE |
427 		FLEXCAN_QUIRK_SUPPORT_FD | FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW |
428 		FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX |
429 		FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX_RTR,
430 };
431 
432 static struct flexcan_devtype_data fsl_imx8mp_devtype_data = {
433 	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
434 		FLEXCAN_QUIRK_DISABLE_MECR | FLEXCAN_QUIRK_USE_RX_MAILBOX |
435 		FLEXCAN_QUIRK_BROKEN_PERR_STATE | FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR |
436 		FLEXCAN_QUIRK_SUPPORT_FD | FLEXCAN_QUIRK_SUPPORT_ECC |
437 		FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX |
438 		FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX_RTR,
439 };
440 
441 static const struct flexcan_devtype_data fsl_vf610_devtype_data = {
442 	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
443 		FLEXCAN_QUIRK_DISABLE_MECR | FLEXCAN_QUIRK_USE_RX_MAILBOX |
444 		FLEXCAN_QUIRK_BROKEN_PERR_STATE | FLEXCAN_QUIRK_SUPPORT_ECC |
445 		FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX |
446 		FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX_RTR,
447 };
448 
449 static const struct flexcan_devtype_data fsl_ls1021a_r2_devtype_data = {
450 	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
451 		FLEXCAN_QUIRK_BROKEN_PERR_STATE | FLEXCAN_QUIRK_USE_RX_MAILBOX |
452 		FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX |
453 		FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX_RTR,
454 };
455 
456 static const struct flexcan_devtype_data fsl_lx2160a_r1_devtype_data = {
457 	.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
458 		FLEXCAN_QUIRK_DISABLE_MECR | FLEXCAN_QUIRK_BROKEN_PERR_STATE |
459 		FLEXCAN_QUIRK_USE_RX_MAILBOX | FLEXCAN_QUIRK_SUPPORT_FD |
460 		FLEXCAN_QUIRK_SUPPORT_ECC |
461 		FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX |
462 		FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX_RTR,
463 };
464 
465 static const struct can_bittiming_const flexcan_bittiming_const = {
466 	.name = DRV_NAME,
467 	.tseg1_min = 4,
468 	.tseg1_max = 16,
469 	.tseg2_min = 2,
470 	.tseg2_max = 8,
471 	.sjw_max = 4,
472 	.brp_min = 1,
473 	.brp_max = 256,
474 	.brp_inc = 1,
475 };
476 
477 static const struct can_bittiming_const flexcan_fd_bittiming_const = {
478 	.name = DRV_NAME,
479 	.tseg1_min = 2,
480 	.tseg1_max = 96,
481 	.tseg2_min = 2,
482 	.tseg2_max = 32,
483 	.sjw_max = 16,
484 	.brp_min = 1,
485 	.brp_max = 1024,
486 	.brp_inc = 1,
487 };
488 
489 static const struct can_bittiming_const flexcan_fd_data_bittiming_const = {
490 	.name = DRV_NAME,
491 	.tseg1_min = 2,
492 	.tseg1_max = 39,
493 	.tseg2_min = 2,
494 	.tseg2_max = 8,
495 	.sjw_max = 4,
496 	.brp_min = 1,
497 	.brp_max = 1024,
498 	.brp_inc = 1,
499 };
500 
501 /* FlexCAN module is essentially modelled as a little-endian IP in most
502  * SoCs, i.e the registers as well as the message buffer areas are
503  * implemented in a little-endian fashion.
504  *
505  * However there are some SoCs (e.g. LS1021A) which implement the FlexCAN
506  * module in a big-endian fashion (i.e the registers as well as the
507  * message buffer areas are implemented in a big-endian way).
508  *
509  * In addition, the FlexCAN module can be found on SoCs having ARM or
510  * PPC cores. So, we need to abstract off the register read/write
511  * functions, ensuring that these cater to all the combinations of module
512  * endianness and underlying CPU endianness.
513  */
flexcan_read_be(void __iomem * addr)514 static inline u32 flexcan_read_be(void __iomem *addr)
515 {
516 	return ioread32be(addr);
517 }
518 
flexcan_write_be(u32 val,void __iomem * addr)519 static inline void flexcan_write_be(u32 val, void __iomem *addr)
520 {
521 	iowrite32be(val, addr);
522 }
523 
flexcan_read_le(void __iomem * addr)524 static inline u32 flexcan_read_le(void __iomem *addr)
525 {
526 	return ioread32(addr);
527 }
528 
flexcan_write_le(u32 val,void __iomem * addr)529 static inline void flexcan_write_le(u32 val, void __iomem *addr)
530 {
531 	iowrite32(val, addr);
532 }
533 
flexcan_get_mb(const struct flexcan_priv * priv,u8 mb_index)534 static struct flexcan_mb __iomem *flexcan_get_mb(const struct flexcan_priv *priv,
535 						 u8 mb_index)
536 {
537 	u8 bank_size;
538 	bool bank;
539 
540 	if (WARN_ON(mb_index >= priv->mb_count))
541 		return NULL;
542 
543 	bank_size = sizeof(priv->regs->mb[0]) / priv->mb_size;
544 
545 	bank = mb_index >= bank_size;
546 	if (bank)
547 		mb_index -= bank_size;
548 
549 	return (struct flexcan_mb __iomem *)
550 		(&priv->regs->mb[bank][priv->mb_size * mb_index]);
551 }
552 
flexcan_low_power_enter_ack(struct flexcan_priv * priv)553 static int flexcan_low_power_enter_ack(struct flexcan_priv *priv)
554 {
555 	struct flexcan_regs __iomem *regs = priv->regs;
556 	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
557 
558 	while (timeout-- && !(priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
559 		udelay(10);
560 
561 	if (!(priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
562 		return -ETIMEDOUT;
563 
564 	return 0;
565 }
566 
flexcan_low_power_exit_ack(struct flexcan_priv * priv)567 static int flexcan_low_power_exit_ack(struct flexcan_priv *priv)
568 {
569 	struct flexcan_regs __iomem *regs = priv->regs;
570 	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
571 
572 	while (timeout-- && (priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
573 		udelay(10);
574 
575 	if (priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK)
576 		return -ETIMEDOUT;
577 
578 	return 0;
579 }
580 
flexcan_enable_wakeup_irq(struct flexcan_priv * priv,bool enable)581 static void flexcan_enable_wakeup_irq(struct flexcan_priv *priv, bool enable)
582 {
583 	struct flexcan_regs __iomem *regs = priv->regs;
584 	u32 reg_mcr;
585 
586 	reg_mcr = priv->read(&regs->mcr);
587 
588 	if (enable)
589 		reg_mcr |= FLEXCAN_MCR_WAK_MSK;
590 	else
591 		reg_mcr &= ~FLEXCAN_MCR_WAK_MSK;
592 
593 	priv->write(reg_mcr, &regs->mcr);
594 }
595 
flexcan_stop_mode_enable_scfw(struct flexcan_priv * priv,bool enabled)596 static int flexcan_stop_mode_enable_scfw(struct flexcan_priv *priv, bool enabled)
597 {
598 	u8 idx = priv->scu_idx;
599 	u32 rsrc_id, val;
600 
601 	rsrc_id = IMX_SC_R_CAN(idx);
602 
603 	if (enabled)
604 		val = 1;
605 	else
606 		val = 0;
607 
608 	/* stop mode request via scu firmware */
609 	return imx_sc_misc_set_control(priv->sc_ipc_handle, rsrc_id,
610 				       IMX_SC_C_IPG_STOP, val);
611 }
612 
flexcan_enter_stop_mode(struct flexcan_priv * priv)613 static inline int flexcan_enter_stop_mode(struct flexcan_priv *priv)
614 {
615 	struct flexcan_regs __iomem *regs = priv->regs;
616 	u32 reg_mcr;
617 	int ret;
618 
619 	reg_mcr = priv->read(&regs->mcr);
620 	reg_mcr |= FLEXCAN_MCR_SLF_WAK;
621 	priv->write(reg_mcr, &regs->mcr);
622 
623 	/* enable stop request */
624 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW) {
625 		ret = flexcan_stop_mode_enable_scfw(priv, true);
626 		if (ret < 0)
627 			return ret;
628 	} else {
629 		regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr,
630 				   1 << priv->stm.req_bit, 1 << priv->stm.req_bit);
631 	}
632 
633 	return flexcan_low_power_enter_ack(priv);
634 }
635 
flexcan_exit_stop_mode(struct flexcan_priv * priv)636 static inline int flexcan_exit_stop_mode(struct flexcan_priv *priv)
637 {
638 	struct flexcan_regs __iomem *regs = priv->regs;
639 	u32 reg_mcr;
640 	int ret;
641 
642 	/* remove stop request */
643 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW) {
644 		ret = flexcan_stop_mode_enable_scfw(priv, false);
645 		if (ret < 0)
646 			return ret;
647 	} else {
648 		regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr,
649 				   1 << priv->stm.req_bit, 0);
650 	}
651 
652 	reg_mcr = priv->read(&regs->mcr);
653 	reg_mcr &= ~FLEXCAN_MCR_SLF_WAK;
654 	priv->write(reg_mcr, &regs->mcr);
655 
656 	return flexcan_low_power_exit_ack(priv);
657 }
658 
flexcan_error_irq_enable(const struct flexcan_priv * priv)659 static inline void flexcan_error_irq_enable(const struct flexcan_priv *priv)
660 {
661 	struct flexcan_regs __iomem *regs = priv->regs;
662 	u32 reg_ctrl = (priv->reg_ctrl_default | FLEXCAN_CTRL_ERR_MSK);
663 
664 	priv->write(reg_ctrl, &regs->ctrl);
665 }
666 
flexcan_error_irq_disable(const struct flexcan_priv * priv)667 static inline void flexcan_error_irq_disable(const struct flexcan_priv *priv)
668 {
669 	struct flexcan_regs __iomem *regs = priv->regs;
670 	u32 reg_ctrl = (priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_MSK);
671 
672 	priv->write(reg_ctrl, &regs->ctrl);
673 }
674 
flexcan_clks_enable(const struct flexcan_priv * priv)675 static int flexcan_clks_enable(const struct flexcan_priv *priv)
676 {
677 	int err = 0;
678 
679 	if (priv->clk_ipg) {
680 		err = clk_prepare_enable(priv->clk_ipg);
681 		if (err)
682 			return err;
683 	}
684 
685 	if (priv->clk_per) {
686 		err = clk_prepare_enable(priv->clk_per);
687 		if (err)
688 			clk_disable_unprepare(priv->clk_ipg);
689 	}
690 
691 	return err;
692 }
693 
flexcan_clks_disable(const struct flexcan_priv * priv)694 static void flexcan_clks_disable(const struct flexcan_priv *priv)
695 {
696 	clk_disable_unprepare(priv->clk_per);
697 	clk_disable_unprepare(priv->clk_ipg);
698 }
699 
flexcan_transceiver_enable(const struct flexcan_priv * priv)700 static inline int flexcan_transceiver_enable(const struct flexcan_priv *priv)
701 {
702 	if (!priv->reg_xceiver)
703 		return 0;
704 
705 	return regulator_enable(priv->reg_xceiver);
706 }
707 
flexcan_transceiver_disable(const struct flexcan_priv * priv)708 static inline int flexcan_transceiver_disable(const struct flexcan_priv *priv)
709 {
710 	if (!priv->reg_xceiver)
711 		return 0;
712 
713 	return regulator_disable(priv->reg_xceiver);
714 }
715 
flexcan_chip_enable(struct flexcan_priv * priv)716 static int flexcan_chip_enable(struct flexcan_priv *priv)
717 {
718 	struct flexcan_regs __iomem *regs = priv->regs;
719 	u32 reg;
720 
721 	reg = priv->read(&regs->mcr);
722 	reg &= ~FLEXCAN_MCR_MDIS;
723 	priv->write(reg, &regs->mcr);
724 
725 	return flexcan_low_power_exit_ack(priv);
726 }
727 
flexcan_chip_disable(struct flexcan_priv * priv)728 static int flexcan_chip_disable(struct flexcan_priv *priv)
729 {
730 	struct flexcan_regs __iomem *regs = priv->regs;
731 	u32 reg;
732 
733 	reg = priv->read(&regs->mcr);
734 	reg |= FLEXCAN_MCR_MDIS;
735 	priv->write(reg, &regs->mcr);
736 
737 	return flexcan_low_power_enter_ack(priv);
738 }
739 
flexcan_chip_freeze(struct flexcan_priv * priv)740 static int flexcan_chip_freeze(struct flexcan_priv *priv)
741 {
742 	struct flexcan_regs __iomem *regs = priv->regs;
743 	unsigned int timeout;
744 	u32 bitrate = priv->can.bittiming.bitrate;
745 	u32 reg;
746 
747 	if (bitrate)
748 		timeout = 1000 * 1000 * 10 / bitrate;
749 	else
750 		timeout = FLEXCAN_TIMEOUT_US / 10;
751 
752 	reg = priv->read(&regs->mcr);
753 	reg |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_HALT;
754 	priv->write(reg, &regs->mcr);
755 
756 	while (timeout-- && !(priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
757 		udelay(100);
758 
759 	if (!(priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
760 		return -ETIMEDOUT;
761 
762 	return 0;
763 }
764 
flexcan_chip_unfreeze(struct flexcan_priv * priv)765 static int flexcan_chip_unfreeze(struct flexcan_priv *priv)
766 {
767 	struct flexcan_regs __iomem *regs = priv->regs;
768 	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
769 	u32 reg;
770 
771 	reg = priv->read(&regs->mcr);
772 	reg &= ~FLEXCAN_MCR_HALT;
773 	priv->write(reg, &regs->mcr);
774 
775 	while (timeout-- && (priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
776 		udelay(10);
777 
778 	if (priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK)
779 		return -ETIMEDOUT;
780 
781 	return 0;
782 }
783 
flexcan_chip_softreset(struct flexcan_priv * priv)784 static int flexcan_chip_softreset(struct flexcan_priv *priv)
785 {
786 	struct flexcan_regs __iomem *regs = priv->regs;
787 	unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
788 
789 	priv->write(FLEXCAN_MCR_SOFTRST, &regs->mcr);
790 	while (timeout-- && (priv->read(&regs->mcr) & FLEXCAN_MCR_SOFTRST))
791 		udelay(10);
792 
793 	if (priv->read(&regs->mcr) & FLEXCAN_MCR_SOFTRST)
794 		return -ETIMEDOUT;
795 
796 	return 0;
797 }
798 
__flexcan_get_berr_counter(const struct net_device * dev,struct can_berr_counter * bec)799 static int __flexcan_get_berr_counter(const struct net_device *dev,
800 				      struct can_berr_counter *bec)
801 {
802 	const struct flexcan_priv *priv = netdev_priv(dev);
803 	struct flexcan_regs __iomem *regs = priv->regs;
804 	u32 reg = priv->read(&regs->ecr);
805 
806 	bec->txerr = (reg >> 0) & 0xff;
807 	bec->rxerr = (reg >> 8) & 0xff;
808 
809 	return 0;
810 }
811 
flexcan_get_berr_counter(const struct net_device * dev,struct can_berr_counter * bec)812 static int flexcan_get_berr_counter(const struct net_device *dev,
813 				    struct can_berr_counter *bec)
814 {
815 	const struct flexcan_priv *priv = netdev_priv(dev);
816 	int err;
817 
818 	err = pm_runtime_get_sync(priv->dev);
819 	if (err < 0) {
820 		pm_runtime_put_noidle(priv->dev);
821 		return err;
822 	}
823 
824 	err = __flexcan_get_berr_counter(dev, bec);
825 
826 	pm_runtime_put(priv->dev);
827 
828 	return err;
829 }
830 
flexcan_start_xmit(struct sk_buff * skb,struct net_device * dev)831 static netdev_tx_t flexcan_start_xmit(struct sk_buff *skb, struct net_device *dev)
832 {
833 	const struct flexcan_priv *priv = netdev_priv(dev);
834 	struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
835 	u32 can_id;
836 	u32 data;
837 	u32 ctrl = FLEXCAN_MB_CODE_TX_DATA | ((can_fd_len2dlc(cfd->len)) << 16);
838 	int i;
839 
840 	if (can_dropped_invalid_skb(dev, skb))
841 		return NETDEV_TX_OK;
842 
843 	netif_stop_queue(dev);
844 
845 	if (cfd->can_id & CAN_EFF_FLAG) {
846 		can_id = cfd->can_id & CAN_EFF_MASK;
847 		ctrl |= FLEXCAN_MB_CNT_IDE | FLEXCAN_MB_CNT_SRR;
848 	} else {
849 		can_id = (cfd->can_id & CAN_SFF_MASK) << 18;
850 	}
851 
852 	if (cfd->can_id & CAN_RTR_FLAG)
853 		ctrl |= FLEXCAN_MB_CNT_RTR;
854 
855 	if (can_is_canfd_skb(skb)) {
856 		ctrl |= FLEXCAN_MB_CNT_EDL;
857 
858 		if (cfd->flags & CANFD_BRS)
859 			ctrl |= FLEXCAN_MB_CNT_BRS;
860 	}
861 
862 	for (i = 0; i < cfd->len; i += sizeof(u32)) {
863 		data = be32_to_cpup((__be32 *)&cfd->data[i]);
864 		priv->write(data, &priv->tx_mb->data[i / sizeof(u32)]);
865 	}
866 
867 	can_put_echo_skb(skb, dev, 0, 0);
868 
869 	priv->write(can_id, &priv->tx_mb->can_id);
870 	priv->write(ctrl, &priv->tx_mb->can_ctrl);
871 
872 	/* Errata ERR005829 step8:
873 	 * Write twice INACTIVE(0x8) code to first MB.
874 	 */
875 	priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
876 		    &priv->tx_mb_reserved->can_ctrl);
877 	priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
878 		    &priv->tx_mb_reserved->can_ctrl);
879 
880 	return NETDEV_TX_OK;
881 }
882 
flexcan_irq_bus_err(struct net_device * dev,u32 reg_esr)883 static void flexcan_irq_bus_err(struct net_device *dev, u32 reg_esr)
884 {
885 	struct flexcan_priv *priv = netdev_priv(dev);
886 	struct flexcan_regs __iomem *regs = priv->regs;
887 	struct sk_buff *skb;
888 	struct can_frame *cf;
889 	bool rx_errors = false, tx_errors = false;
890 	u32 timestamp;
891 	int err;
892 
893 	timestamp = priv->read(&regs->timer) << 16;
894 
895 	skb = alloc_can_err_skb(dev, &cf);
896 	if (unlikely(!skb))
897 		return;
898 
899 	cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
900 
901 	if (reg_esr & FLEXCAN_ESR_BIT1_ERR) {
902 		netdev_dbg(dev, "BIT1_ERR irq\n");
903 		cf->data[2] |= CAN_ERR_PROT_BIT1;
904 		tx_errors = true;
905 	}
906 	if (reg_esr & FLEXCAN_ESR_BIT0_ERR) {
907 		netdev_dbg(dev, "BIT0_ERR irq\n");
908 		cf->data[2] |= CAN_ERR_PROT_BIT0;
909 		tx_errors = true;
910 	}
911 	if (reg_esr & FLEXCAN_ESR_ACK_ERR) {
912 		netdev_dbg(dev, "ACK_ERR irq\n");
913 		cf->can_id |= CAN_ERR_ACK;
914 		cf->data[3] = CAN_ERR_PROT_LOC_ACK;
915 		tx_errors = true;
916 	}
917 	if (reg_esr & FLEXCAN_ESR_CRC_ERR) {
918 		netdev_dbg(dev, "CRC_ERR irq\n");
919 		cf->data[2] |= CAN_ERR_PROT_BIT;
920 		cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
921 		rx_errors = true;
922 	}
923 	if (reg_esr & FLEXCAN_ESR_FRM_ERR) {
924 		netdev_dbg(dev, "FRM_ERR irq\n");
925 		cf->data[2] |= CAN_ERR_PROT_FORM;
926 		rx_errors = true;
927 	}
928 	if (reg_esr & FLEXCAN_ESR_STF_ERR) {
929 		netdev_dbg(dev, "STF_ERR irq\n");
930 		cf->data[2] |= CAN_ERR_PROT_STUFF;
931 		rx_errors = true;
932 	}
933 
934 	priv->can.can_stats.bus_error++;
935 	if (rx_errors)
936 		dev->stats.rx_errors++;
937 	if (tx_errors)
938 		dev->stats.tx_errors++;
939 
940 	err = can_rx_offload_queue_sorted(&priv->offload, skb, timestamp);
941 	if (err)
942 		dev->stats.rx_fifo_errors++;
943 }
944 
flexcan_irq_state(struct net_device * dev,u32 reg_esr)945 static void flexcan_irq_state(struct net_device *dev, u32 reg_esr)
946 {
947 	struct flexcan_priv *priv = netdev_priv(dev);
948 	struct flexcan_regs __iomem *regs = priv->regs;
949 	struct sk_buff *skb;
950 	struct can_frame *cf;
951 	enum can_state new_state, rx_state, tx_state;
952 	int flt;
953 	struct can_berr_counter bec;
954 	u32 timestamp;
955 	int err;
956 
957 	flt = reg_esr & FLEXCAN_ESR_FLT_CONF_MASK;
958 	if (likely(flt == FLEXCAN_ESR_FLT_CONF_ACTIVE)) {
959 		tx_state = unlikely(reg_esr & FLEXCAN_ESR_TX_WRN) ?
960 			CAN_STATE_ERROR_WARNING : CAN_STATE_ERROR_ACTIVE;
961 		rx_state = unlikely(reg_esr & FLEXCAN_ESR_RX_WRN) ?
962 			CAN_STATE_ERROR_WARNING : CAN_STATE_ERROR_ACTIVE;
963 		new_state = max(tx_state, rx_state);
964 	} else {
965 		__flexcan_get_berr_counter(dev, &bec);
966 		new_state = flt == FLEXCAN_ESR_FLT_CONF_PASSIVE ?
967 			CAN_STATE_ERROR_PASSIVE : CAN_STATE_BUS_OFF;
968 		rx_state = bec.rxerr >= bec.txerr ? new_state : 0;
969 		tx_state = bec.rxerr <= bec.txerr ? new_state : 0;
970 	}
971 
972 	/* state hasn't changed */
973 	if (likely(new_state == priv->can.state))
974 		return;
975 
976 	timestamp = priv->read(&regs->timer) << 16;
977 
978 	skb = alloc_can_err_skb(dev, &cf);
979 	if (unlikely(!skb))
980 		return;
981 
982 	can_change_state(dev, cf, tx_state, rx_state);
983 
984 	if (unlikely(new_state == CAN_STATE_BUS_OFF))
985 		can_bus_off(dev);
986 
987 	err = can_rx_offload_queue_sorted(&priv->offload, skb, timestamp);
988 	if (err)
989 		dev->stats.rx_fifo_errors++;
990 }
991 
flexcan_read64_mask(struct flexcan_priv * priv,void __iomem * addr,u64 mask)992 static inline u64 flexcan_read64_mask(struct flexcan_priv *priv, void __iomem *addr, u64 mask)
993 {
994 	u64 reg = 0;
995 
996 	if (upper_32_bits(mask))
997 		reg = (u64)priv->read(addr - 4) << 32;
998 	if (lower_32_bits(mask))
999 		reg |= priv->read(addr);
1000 
1001 	return reg & mask;
1002 }
1003 
flexcan_write64(struct flexcan_priv * priv,u64 val,void __iomem * addr)1004 static inline void flexcan_write64(struct flexcan_priv *priv, u64 val, void __iomem *addr)
1005 {
1006 	if (upper_32_bits(val))
1007 		priv->write(upper_32_bits(val), addr - 4);
1008 	if (lower_32_bits(val))
1009 		priv->write(lower_32_bits(val), addr);
1010 }
1011 
flexcan_read_reg_iflag_rx(struct flexcan_priv * priv)1012 static inline u64 flexcan_read_reg_iflag_rx(struct flexcan_priv *priv)
1013 {
1014 	return flexcan_read64_mask(priv, &priv->regs->iflag1, priv->rx_mask);
1015 }
1016 
flexcan_read_reg_iflag_tx(struct flexcan_priv * priv)1017 static inline u64 flexcan_read_reg_iflag_tx(struct flexcan_priv *priv)
1018 {
1019 	return flexcan_read64_mask(priv, &priv->regs->iflag1, priv->tx_mask);
1020 }
1021 
rx_offload_to_priv(struct can_rx_offload * offload)1022 static inline struct flexcan_priv *rx_offload_to_priv(struct can_rx_offload *offload)
1023 {
1024 	return container_of(offload, struct flexcan_priv, offload);
1025 }
1026 
flexcan_mailbox_read(struct can_rx_offload * offload,unsigned int n,u32 * timestamp,bool drop)1027 static struct sk_buff *flexcan_mailbox_read(struct can_rx_offload *offload,
1028 					    unsigned int n, u32 *timestamp,
1029 					    bool drop)
1030 {
1031 	struct flexcan_priv *priv = rx_offload_to_priv(offload);
1032 	struct flexcan_regs __iomem *regs = priv->regs;
1033 	struct flexcan_mb __iomem *mb;
1034 	struct sk_buff *skb;
1035 	struct canfd_frame *cfd;
1036 	u32 reg_ctrl, reg_id, reg_iflag1;
1037 	int i;
1038 
1039 	mb = flexcan_get_mb(priv, n);
1040 
1041 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX) {
1042 		u32 code;
1043 
1044 		do {
1045 			reg_ctrl = priv->read(&mb->can_ctrl);
1046 		} while (reg_ctrl & FLEXCAN_MB_CODE_RX_BUSY_BIT);
1047 
1048 		/* is this MB empty? */
1049 		code = reg_ctrl & FLEXCAN_MB_CODE_MASK;
1050 		if ((code != FLEXCAN_MB_CODE_RX_FULL) &&
1051 		    (code != FLEXCAN_MB_CODE_RX_OVERRUN))
1052 			return NULL;
1053 
1054 		if (code == FLEXCAN_MB_CODE_RX_OVERRUN) {
1055 			/* This MB was overrun, we lost data */
1056 			offload->dev->stats.rx_over_errors++;
1057 			offload->dev->stats.rx_errors++;
1058 		}
1059 	} else {
1060 		reg_iflag1 = priv->read(&regs->iflag1);
1061 		if (!(reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE))
1062 			return NULL;
1063 
1064 		reg_ctrl = priv->read(&mb->can_ctrl);
1065 	}
1066 
1067 	if (unlikely(drop)) {
1068 		skb = ERR_PTR(-ENOBUFS);
1069 		goto mark_as_read;
1070 	}
1071 
1072 	if (reg_ctrl & FLEXCAN_MB_CNT_EDL)
1073 		skb = alloc_canfd_skb(offload->dev, &cfd);
1074 	else
1075 		skb = alloc_can_skb(offload->dev, (struct can_frame **)&cfd);
1076 	if (unlikely(!skb)) {
1077 		skb = ERR_PTR(-ENOMEM);
1078 		goto mark_as_read;
1079 	}
1080 
1081 	/* increase timstamp to full 32 bit */
1082 	*timestamp = reg_ctrl << 16;
1083 
1084 	reg_id = priv->read(&mb->can_id);
1085 	if (reg_ctrl & FLEXCAN_MB_CNT_IDE)
1086 		cfd->can_id = ((reg_id >> 0) & CAN_EFF_MASK) | CAN_EFF_FLAG;
1087 	else
1088 		cfd->can_id = (reg_id >> 18) & CAN_SFF_MASK;
1089 
1090 	if (reg_ctrl & FLEXCAN_MB_CNT_EDL) {
1091 		cfd->len = can_fd_dlc2len((reg_ctrl >> 16) & 0xf);
1092 
1093 		if (reg_ctrl & FLEXCAN_MB_CNT_BRS)
1094 			cfd->flags |= CANFD_BRS;
1095 	} else {
1096 		cfd->len = can_cc_dlc2len((reg_ctrl >> 16) & 0xf);
1097 
1098 		if (reg_ctrl & FLEXCAN_MB_CNT_RTR)
1099 			cfd->can_id |= CAN_RTR_FLAG;
1100 	}
1101 
1102 	if (reg_ctrl & FLEXCAN_MB_CNT_ESI)
1103 		cfd->flags |= CANFD_ESI;
1104 
1105 	for (i = 0; i < cfd->len; i += sizeof(u32)) {
1106 		__be32 data = cpu_to_be32(priv->read(&mb->data[i / sizeof(u32)]));
1107 		*(__be32 *)(cfd->data + i) = data;
1108 	}
1109 
1110  mark_as_read:
1111 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX)
1112 		flexcan_write64(priv, FLEXCAN_IFLAG_MB(n), &regs->iflag1);
1113 	else
1114 		priv->write(FLEXCAN_IFLAG_RX_FIFO_AVAILABLE, &regs->iflag1);
1115 
1116 	/* Read the Free Running Timer. It is optional but recommended
1117 	 * to unlock Mailbox as soon as possible and make it available
1118 	 * for reception.
1119 	 */
1120 	priv->read(&regs->timer);
1121 
1122 	return skb;
1123 }
1124 
flexcan_irq(int irq,void * dev_id)1125 static irqreturn_t flexcan_irq(int irq, void *dev_id)
1126 {
1127 	struct net_device *dev = dev_id;
1128 	struct net_device_stats *stats = &dev->stats;
1129 	struct flexcan_priv *priv = netdev_priv(dev);
1130 	struct flexcan_regs __iomem *regs = priv->regs;
1131 	irqreturn_t handled = IRQ_NONE;
1132 	u64 reg_iflag_tx;
1133 	u32 reg_esr;
1134 	enum can_state last_state = priv->can.state;
1135 
1136 	/* reception interrupt */
1137 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX) {
1138 		u64 reg_iflag_rx;
1139 		int ret;
1140 
1141 		while ((reg_iflag_rx = flexcan_read_reg_iflag_rx(priv))) {
1142 			handled = IRQ_HANDLED;
1143 			ret = can_rx_offload_irq_offload_timestamp(&priv->offload,
1144 								   reg_iflag_rx);
1145 			if (!ret)
1146 				break;
1147 		}
1148 	} else {
1149 		u32 reg_iflag1;
1150 
1151 		reg_iflag1 = priv->read(&regs->iflag1);
1152 		if (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE) {
1153 			handled = IRQ_HANDLED;
1154 			can_rx_offload_irq_offload_fifo(&priv->offload);
1155 		}
1156 
1157 		/* FIFO overflow interrupt */
1158 		if (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_OVERFLOW) {
1159 			handled = IRQ_HANDLED;
1160 			priv->write(FLEXCAN_IFLAG_RX_FIFO_OVERFLOW,
1161 				    &regs->iflag1);
1162 			dev->stats.rx_over_errors++;
1163 			dev->stats.rx_errors++;
1164 		}
1165 	}
1166 
1167 	reg_iflag_tx = flexcan_read_reg_iflag_tx(priv);
1168 
1169 	/* transmission complete interrupt */
1170 	if (reg_iflag_tx & priv->tx_mask) {
1171 		u32 reg_ctrl = priv->read(&priv->tx_mb->can_ctrl);
1172 
1173 		handled = IRQ_HANDLED;
1174 		stats->tx_bytes +=
1175 			can_rx_offload_get_echo_skb(&priv->offload, 0,
1176 						    reg_ctrl << 16, NULL);
1177 		stats->tx_packets++;
1178 		can_led_event(dev, CAN_LED_EVENT_TX);
1179 
1180 		/* after sending a RTR frame MB is in RX mode */
1181 		priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
1182 			    &priv->tx_mb->can_ctrl);
1183 		flexcan_write64(priv, priv->tx_mask, &regs->iflag1);
1184 		netif_wake_queue(dev);
1185 	}
1186 
1187 	reg_esr = priv->read(&regs->esr);
1188 
1189 	/* ACK all bus error, state change and wake IRQ sources */
1190 	if (reg_esr & (FLEXCAN_ESR_ALL_INT | FLEXCAN_ESR_WAK_INT)) {
1191 		handled = IRQ_HANDLED;
1192 		priv->write(reg_esr & (FLEXCAN_ESR_ALL_INT | FLEXCAN_ESR_WAK_INT), &regs->esr);
1193 	}
1194 
1195 	/* state change interrupt or broken error state quirk fix is enabled */
1196 	if ((reg_esr & FLEXCAN_ESR_ERR_STATE) ||
1197 	    (priv->devtype_data.quirks & (FLEXCAN_QUIRK_BROKEN_WERR_STATE |
1198 					   FLEXCAN_QUIRK_BROKEN_PERR_STATE)))
1199 		flexcan_irq_state(dev, reg_esr);
1200 
1201 	/* bus error IRQ - handle if bus error reporting is activated */
1202 	if ((reg_esr & FLEXCAN_ESR_ERR_BUS) &&
1203 	    (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
1204 		flexcan_irq_bus_err(dev, reg_esr);
1205 
1206 	/* availability of error interrupt among state transitions in case
1207 	 * bus error reporting is de-activated and
1208 	 * FLEXCAN_QUIRK_BROKEN_PERR_STATE is enabled:
1209 	 *  +--------------------------------------------------------------+
1210 	 *  | +----------------------------------------------+ [stopped /  |
1211 	 *  | |                                              |  sleeping] -+
1212 	 *  +-+-> active <-> warning <-> passive -> bus off -+
1213 	 *        ___________^^^^^^^^^^^^_______________________________
1214 	 *        disabled(1)  enabled             disabled
1215 	 *
1216 	 * (1): enabled if FLEXCAN_QUIRK_BROKEN_WERR_STATE is enabled
1217 	 */
1218 	if ((last_state != priv->can.state) &&
1219 	    (priv->devtype_data.quirks & FLEXCAN_QUIRK_BROKEN_PERR_STATE) &&
1220 	    !(priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)) {
1221 		switch (priv->can.state) {
1222 		case CAN_STATE_ERROR_ACTIVE:
1223 			if (priv->devtype_data.quirks &
1224 			    FLEXCAN_QUIRK_BROKEN_WERR_STATE)
1225 				flexcan_error_irq_enable(priv);
1226 			else
1227 				flexcan_error_irq_disable(priv);
1228 			break;
1229 
1230 		case CAN_STATE_ERROR_WARNING:
1231 			flexcan_error_irq_enable(priv);
1232 			break;
1233 
1234 		case CAN_STATE_ERROR_PASSIVE:
1235 		case CAN_STATE_BUS_OFF:
1236 			flexcan_error_irq_disable(priv);
1237 			break;
1238 
1239 		default:
1240 			break;
1241 		}
1242 	}
1243 
1244 	if (handled)
1245 		can_rx_offload_irq_finish(&priv->offload);
1246 
1247 	return handled;
1248 }
1249 
flexcan_set_bittiming_ctrl(const struct net_device * dev)1250 static void flexcan_set_bittiming_ctrl(const struct net_device *dev)
1251 {
1252 	const struct flexcan_priv *priv = netdev_priv(dev);
1253 	const struct can_bittiming *bt = &priv->can.bittiming;
1254 	struct flexcan_regs __iomem *regs = priv->regs;
1255 	u32 reg;
1256 
1257 	reg = priv->read(&regs->ctrl);
1258 	reg &= ~(FLEXCAN_CTRL_PRESDIV(0xff) |
1259 		 FLEXCAN_CTRL_RJW(0x3) |
1260 		 FLEXCAN_CTRL_PSEG1(0x7) |
1261 		 FLEXCAN_CTRL_PSEG2(0x7) |
1262 		 FLEXCAN_CTRL_PROPSEG(0x7));
1263 
1264 	reg |= FLEXCAN_CTRL_PRESDIV(bt->brp - 1) |
1265 		FLEXCAN_CTRL_PSEG1(bt->phase_seg1 - 1) |
1266 		FLEXCAN_CTRL_PSEG2(bt->phase_seg2 - 1) |
1267 		FLEXCAN_CTRL_RJW(bt->sjw - 1) |
1268 		FLEXCAN_CTRL_PROPSEG(bt->prop_seg - 1);
1269 
1270 	netdev_dbg(dev, "writing ctrl=0x%08x\n", reg);
1271 	priv->write(reg, &regs->ctrl);
1272 
1273 	/* print chip status */
1274 	netdev_dbg(dev, "%s: mcr=0x%08x ctrl=0x%08x\n", __func__,
1275 		   priv->read(&regs->mcr), priv->read(&regs->ctrl));
1276 }
1277 
flexcan_set_bittiming_cbt(const struct net_device * dev)1278 static void flexcan_set_bittiming_cbt(const struct net_device *dev)
1279 {
1280 	struct flexcan_priv *priv = netdev_priv(dev);
1281 	struct can_bittiming *bt = &priv->can.bittiming;
1282 	struct can_bittiming *dbt = &priv->can.data_bittiming;
1283 	struct flexcan_regs __iomem *regs = priv->regs;
1284 	u32 reg_cbt, reg_fdctrl;
1285 
1286 	/* CBT */
1287 	/* CBT[EPSEG1] is 5 bit long and CBT[EPROPSEG] is 6 bit
1288 	 * long. The can_calc_bittiming() tries to divide the tseg1
1289 	 * equally between phase_seg1 and prop_seg, which may not fit
1290 	 * in CBT register. Therefore, if phase_seg1 is more than
1291 	 * possible value, increase prop_seg and decrease phase_seg1.
1292 	 */
1293 	if (bt->phase_seg1 > 0x20) {
1294 		bt->prop_seg += (bt->phase_seg1 - 0x20);
1295 		bt->phase_seg1 = 0x20;
1296 	}
1297 
1298 	reg_cbt = FLEXCAN_CBT_BTF |
1299 		FIELD_PREP(FLEXCAN_CBT_EPRESDIV_MASK, bt->brp - 1) |
1300 		FIELD_PREP(FLEXCAN_CBT_ERJW_MASK, bt->sjw - 1) |
1301 		FIELD_PREP(FLEXCAN_CBT_EPROPSEG_MASK, bt->prop_seg - 1) |
1302 		FIELD_PREP(FLEXCAN_CBT_EPSEG1_MASK, bt->phase_seg1 - 1) |
1303 		FIELD_PREP(FLEXCAN_CBT_EPSEG2_MASK, bt->phase_seg2 - 1);
1304 
1305 	netdev_dbg(dev, "writing cbt=0x%08x\n", reg_cbt);
1306 	priv->write(reg_cbt, &regs->cbt);
1307 
1308 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
1309 		u32 reg_fdcbt, reg_ctrl2;
1310 
1311 		if (bt->brp != dbt->brp)
1312 			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",
1313 				    dbt->brp, bt->brp);
1314 
1315 		/* FDCBT */
1316 		/* FDCBT[FPSEG1] is 3 bit long and FDCBT[FPROPSEG] is
1317 		 * 5 bit long. The can_calc_bittiming tries to divide
1318 		 * the tseg1 equally between phase_seg1 and prop_seg,
1319 		 * which may not fit in FDCBT register. Therefore, if
1320 		 * phase_seg1 is more than possible value, increase
1321 		 * prop_seg and decrease phase_seg1
1322 		 */
1323 		if (dbt->phase_seg1 > 0x8) {
1324 			dbt->prop_seg += (dbt->phase_seg1 - 0x8);
1325 			dbt->phase_seg1 = 0x8;
1326 		}
1327 
1328 		reg_fdcbt = priv->read(&regs->fdcbt);
1329 		reg_fdcbt &= ~(FIELD_PREP(FLEXCAN_FDCBT_FPRESDIV_MASK, 0x3ff) |
1330 			       FIELD_PREP(FLEXCAN_FDCBT_FRJW_MASK, 0x7) |
1331 			       FIELD_PREP(FLEXCAN_FDCBT_FPROPSEG_MASK, 0x1f) |
1332 			       FIELD_PREP(FLEXCAN_FDCBT_FPSEG1_MASK, 0x7) |
1333 			       FIELD_PREP(FLEXCAN_FDCBT_FPSEG2_MASK, 0x7));
1334 
1335 		reg_fdcbt |= FIELD_PREP(FLEXCAN_FDCBT_FPRESDIV_MASK, dbt->brp - 1) |
1336 			FIELD_PREP(FLEXCAN_FDCBT_FRJW_MASK, dbt->sjw - 1) |
1337 			FIELD_PREP(FLEXCAN_FDCBT_FPROPSEG_MASK, dbt->prop_seg) |
1338 			FIELD_PREP(FLEXCAN_FDCBT_FPSEG1_MASK, dbt->phase_seg1 - 1) |
1339 			FIELD_PREP(FLEXCAN_FDCBT_FPSEG2_MASK, dbt->phase_seg2 - 1);
1340 
1341 		netdev_dbg(dev, "writing fdcbt=0x%08x\n", reg_fdcbt);
1342 		priv->write(reg_fdcbt, &regs->fdcbt);
1343 
1344 		/* CTRL2 */
1345 		reg_ctrl2 = priv->read(&regs->ctrl2);
1346 		reg_ctrl2 &= ~FLEXCAN_CTRL2_ISOCANFDEN;
1347 		if (!(priv->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO))
1348 			reg_ctrl2 |= FLEXCAN_CTRL2_ISOCANFDEN;
1349 
1350 		netdev_dbg(dev, "writing ctrl2=0x%08x\n", reg_ctrl2);
1351 		priv->write(reg_ctrl2, &regs->ctrl2);
1352 	}
1353 
1354 	/* FDCTRL */
1355 	reg_fdctrl = priv->read(&regs->fdctrl);
1356 	reg_fdctrl &= ~(FLEXCAN_FDCTRL_FDRATE |
1357 			FIELD_PREP(FLEXCAN_FDCTRL_TDCOFF, 0x1f));
1358 
1359 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
1360 		reg_fdctrl |= FLEXCAN_FDCTRL_FDRATE;
1361 
1362 		if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) {
1363 			/* TDC must be disabled for Loop Back mode */
1364 			reg_fdctrl &= ~FLEXCAN_FDCTRL_TDCEN;
1365 		} else {
1366 			reg_fdctrl |= FLEXCAN_FDCTRL_TDCEN |
1367 				FIELD_PREP(FLEXCAN_FDCTRL_TDCOFF,
1368 					   ((dbt->phase_seg1 - 1) +
1369 					    dbt->prop_seg + 2) *
1370 					   ((dbt->brp - 1 ) + 1));
1371 		}
1372 	}
1373 
1374 	netdev_dbg(dev, "writing fdctrl=0x%08x\n", reg_fdctrl);
1375 	priv->write(reg_fdctrl, &regs->fdctrl);
1376 
1377 	netdev_dbg(dev, "%s: mcr=0x%08x ctrl=0x%08x ctrl2=0x%08x fdctrl=0x%08x cbt=0x%08x fdcbt=0x%08x\n",
1378 		   __func__,
1379 		   priv->read(&regs->mcr), priv->read(&regs->ctrl),
1380 		   priv->read(&regs->ctrl2), priv->read(&regs->fdctrl),
1381 		   priv->read(&regs->cbt), priv->read(&regs->fdcbt));
1382 }
1383 
flexcan_set_bittiming(struct net_device * dev)1384 static void flexcan_set_bittiming(struct net_device *dev)
1385 {
1386 	const struct flexcan_priv *priv = netdev_priv(dev);
1387 	struct flexcan_regs __iomem *regs = priv->regs;
1388 	u32 reg;
1389 
1390 	reg = priv->read(&regs->ctrl);
1391 	reg &= ~(FLEXCAN_CTRL_LPB | FLEXCAN_CTRL_SMP |
1392 		 FLEXCAN_CTRL_LOM);
1393 
1394 	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
1395 		reg |= FLEXCAN_CTRL_LPB;
1396 	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
1397 		reg |= FLEXCAN_CTRL_LOM;
1398 	if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
1399 		reg |= FLEXCAN_CTRL_SMP;
1400 
1401 	netdev_dbg(dev, "writing ctrl=0x%08x\n", reg);
1402 	priv->write(reg, &regs->ctrl);
1403 
1404 	if (priv->can.ctrlmode_supported & CAN_CTRLMODE_FD)
1405 		return flexcan_set_bittiming_cbt(dev);
1406 	else
1407 		return flexcan_set_bittiming_ctrl(dev);
1408 }
1409 
flexcan_ram_init(struct net_device * dev)1410 static void flexcan_ram_init(struct net_device *dev)
1411 {
1412 	struct flexcan_priv *priv = netdev_priv(dev);
1413 	struct flexcan_regs __iomem *regs = priv->regs;
1414 	u32 reg_ctrl2;
1415 
1416 	/* 11.8.3.13 Detection and correction of memory errors:
1417 	 * CTRL2[WRMFRZ] grants write access to all memory positions
1418 	 * that require initialization, ranging from 0x080 to 0xADF
1419 	 * and from 0xF28 to 0xFFF when the CAN FD feature is enabled.
1420 	 * The RXMGMASK, RX14MASK, RX15MASK, and RXFGMASK registers
1421 	 * need to be initialized as well. MCR[RFEN] must not be set
1422 	 * during memory initialization.
1423 	 */
1424 	reg_ctrl2 = priv->read(&regs->ctrl2);
1425 	reg_ctrl2 |= FLEXCAN_CTRL2_WRMFRZ;
1426 	priv->write(reg_ctrl2, &regs->ctrl2);
1427 
1428 	memset_io(&regs->mb[0][0], 0,
1429 		  offsetof(struct flexcan_regs, rx_smb1[3]) -
1430 		  offsetof(struct flexcan_regs, mb[0][0]) + 0x4);
1431 
1432 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
1433 		memset_io(&regs->tx_smb_fd[0], 0,
1434 			  offsetof(struct flexcan_regs, rx_smb1_fd[17]) -
1435 			  offsetof(struct flexcan_regs, tx_smb_fd[0]) + 0x4);
1436 
1437 	reg_ctrl2 &= ~FLEXCAN_CTRL2_WRMFRZ;
1438 	priv->write(reg_ctrl2, &regs->ctrl2);
1439 }
1440 
flexcan_rx_offload_setup(struct net_device * dev)1441 static int flexcan_rx_offload_setup(struct net_device *dev)
1442 {
1443 	struct flexcan_priv *priv = netdev_priv(dev);
1444 	int err;
1445 
1446 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
1447 		priv->mb_size = sizeof(struct flexcan_mb) + CANFD_MAX_DLEN;
1448 	else
1449 		priv->mb_size = sizeof(struct flexcan_mb) + CAN_MAX_DLEN;
1450 
1451 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_NR_MB_16)
1452 		priv->mb_count = 16;
1453 	else
1454 		priv->mb_count = (sizeof(priv->regs->mb[0]) / priv->mb_size) +
1455 				 (sizeof(priv->regs->mb[1]) / priv->mb_size);
1456 
1457 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX)
1458 		priv->tx_mb_reserved =
1459 			flexcan_get_mb(priv, FLEXCAN_TX_MB_RESERVED_RX_MAILBOX);
1460 	else
1461 		priv->tx_mb_reserved =
1462 			flexcan_get_mb(priv, FLEXCAN_TX_MB_RESERVED_RX_FIFO);
1463 	priv->tx_mb_idx = priv->mb_count - 1;
1464 	priv->tx_mb = flexcan_get_mb(priv, priv->tx_mb_idx);
1465 	priv->tx_mask = FLEXCAN_IFLAG_MB(priv->tx_mb_idx);
1466 
1467 	priv->offload.mailbox_read = flexcan_mailbox_read;
1468 
1469 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX) {
1470 		priv->offload.mb_first = FLEXCAN_RX_MB_RX_MAILBOX_FIRST;
1471 		priv->offload.mb_last = priv->mb_count - 2;
1472 
1473 		priv->rx_mask = GENMASK_ULL(priv->offload.mb_last,
1474 					    priv->offload.mb_first);
1475 		err = can_rx_offload_add_timestamp(dev, &priv->offload);
1476 	} else {
1477 		priv->rx_mask = FLEXCAN_IFLAG_RX_FIFO_OVERFLOW |
1478 			FLEXCAN_IFLAG_RX_FIFO_AVAILABLE;
1479 		err = can_rx_offload_add_fifo(dev, &priv->offload,
1480 					      FLEXCAN_NAPI_WEIGHT);
1481 	}
1482 
1483 	return err;
1484 }
1485 
flexcan_chip_interrupts_enable(const struct net_device * dev)1486 static void flexcan_chip_interrupts_enable(const struct net_device *dev)
1487 {
1488 	const struct flexcan_priv *priv = netdev_priv(dev);
1489 	struct flexcan_regs __iomem *regs = priv->regs;
1490 	u64 reg_imask;
1491 
1492 	disable_irq(dev->irq);
1493 	priv->write(priv->reg_ctrl_default, &regs->ctrl);
1494 	reg_imask = priv->rx_mask | priv->tx_mask;
1495 	priv->write(upper_32_bits(reg_imask), &regs->imask2);
1496 	priv->write(lower_32_bits(reg_imask), &regs->imask1);
1497 	enable_irq(dev->irq);
1498 }
1499 
flexcan_chip_interrupts_disable(const struct net_device * dev)1500 static void flexcan_chip_interrupts_disable(const struct net_device *dev)
1501 {
1502 	const struct flexcan_priv *priv = netdev_priv(dev);
1503 	struct flexcan_regs __iomem *regs = priv->regs;
1504 
1505 	priv->write(0, &regs->imask2);
1506 	priv->write(0, &regs->imask1);
1507 	priv->write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL,
1508 		    &regs->ctrl);
1509 }
1510 
1511 /* flexcan_chip_start
1512  *
1513  * this functions is entered with clocks enabled
1514  *
1515  */
flexcan_chip_start(struct net_device * dev)1516 static int flexcan_chip_start(struct net_device *dev)
1517 {
1518 	struct flexcan_priv *priv = netdev_priv(dev);
1519 	struct flexcan_regs __iomem *regs = priv->regs;
1520 	u32 reg_mcr, reg_ctrl, reg_ctrl2, reg_mecr;
1521 	int err, i;
1522 	struct flexcan_mb __iomem *mb;
1523 
1524 	/* enable module */
1525 	err = flexcan_chip_enable(priv);
1526 	if (err)
1527 		return err;
1528 
1529 	/* soft reset */
1530 	err = flexcan_chip_softreset(priv);
1531 	if (err)
1532 		goto out_chip_disable;
1533 
1534 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SUPPORT_ECC)
1535 		flexcan_ram_init(dev);
1536 
1537 	flexcan_set_bittiming(dev);
1538 
1539 	/* set freeze, halt */
1540 	err = flexcan_chip_freeze(priv);
1541 	if (err)
1542 		goto out_chip_disable;
1543 
1544 	/* MCR
1545 	 *
1546 	 * only supervisor access
1547 	 * enable warning int
1548 	 * enable individual RX masking
1549 	 * choose format C
1550 	 * set max mailbox number
1551 	 */
1552 	reg_mcr = priv->read(&regs->mcr);
1553 	reg_mcr &= ~FLEXCAN_MCR_MAXMB(0xff);
1554 	reg_mcr |= FLEXCAN_MCR_SUPV | FLEXCAN_MCR_WRN_EN | FLEXCAN_MCR_IRMQ |
1555 		FLEXCAN_MCR_IDAM_C | FLEXCAN_MCR_MAXMB(priv->tx_mb_idx);
1556 
1557 	/* MCR
1558 	 *
1559 	 * FIFO:
1560 	 * - disable for mailbox mode
1561 	 * - enable for FIFO mode
1562 	 */
1563 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX)
1564 		reg_mcr &= ~FLEXCAN_MCR_FEN;
1565 	else
1566 		reg_mcr |= FLEXCAN_MCR_FEN;
1567 
1568 	/* MCR
1569 	 *
1570 	 * NOTE: In loopback mode, the CAN_MCR[SRXDIS] cannot be
1571 	 *       asserted because this will impede the self reception
1572 	 *       of a transmitted message. This is not documented in
1573 	 *       earlier versions of flexcan block guide.
1574 	 *
1575 	 * Self Reception:
1576 	 * - enable Self Reception for loopback mode
1577 	 *   (by clearing "Self Reception Disable" bit)
1578 	 * - disable for normal operation
1579 	 */
1580 	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
1581 		reg_mcr &= ~FLEXCAN_MCR_SRX_DIS;
1582 	else
1583 		reg_mcr |= FLEXCAN_MCR_SRX_DIS;
1584 
1585 	/* MCR - CAN-FD */
1586 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
1587 		reg_mcr |= FLEXCAN_MCR_FDEN;
1588 	else
1589 		reg_mcr &= ~FLEXCAN_MCR_FDEN;
1590 
1591 	netdev_dbg(dev, "%s: writing mcr=0x%08x", __func__, reg_mcr);
1592 	priv->write(reg_mcr, &regs->mcr);
1593 
1594 	/* CTRL
1595 	 *
1596 	 * disable timer sync feature
1597 	 *
1598 	 * disable auto busoff recovery
1599 	 * transmit lowest buffer first
1600 	 *
1601 	 * enable tx and rx warning interrupt
1602 	 * enable bus off interrupt
1603 	 * (== FLEXCAN_CTRL_ERR_STATE)
1604 	 */
1605 	reg_ctrl = priv->read(&regs->ctrl);
1606 	reg_ctrl &= ~FLEXCAN_CTRL_TSYN;
1607 	reg_ctrl |= FLEXCAN_CTRL_BOFF_REC | FLEXCAN_CTRL_LBUF |
1608 		FLEXCAN_CTRL_ERR_STATE;
1609 
1610 	/* enable the "error interrupt" (FLEXCAN_CTRL_ERR_MSK),
1611 	 * on most Flexcan cores, too. Otherwise we don't get
1612 	 * any error warning or passive interrupts.
1613 	 */
1614 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_BROKEN_WERR_STATE ||
1615 	    priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
1616 		reg_ctrl |= FLEXCAN_CTRL_ERR_MSK;
1617 	else
1618 		reg_ctrl &= ~FLEXCAN_CTRL_ERR_MSK;
1619 
1620 	/* save for later use */
1621 	priv->reg_ctrl_default = reg_ctrl;
1622 	/* leave interrupts disabled for now */
1623 	reg_ctrl &= ~FLEXCAN_CTRL_ERR_ALL;
1624 	netdev_dbg(dev, "%s: writing ctrl=0x%08x", __func__, reg_ctrl);
1625 	priv->write(reg_ctrl, &regs->ctrl);
1626 
1627 	if ((priv->devtype_data.quirks & FLEXCAN_QUIRK_ENABLE_EACEN_RRS)) {
1628 		reg_ctrl2 = priv->read(&regs->ctrl2);
1629 		reg_ctrl2 |= FLEXCAN_CTRL2_EACEN | FLEXCAN_CTRL2_RRS;
1630 		priv->write(reg_ctrl2, &regs->ctrl2);
1631 	}
1632 
1633 	if (priv->can.ctrlmode_supported & CAN_CTRLMODE_FD) {
1634 		u32 reg_fdctrl;
1635 
1636 		reg_fdctrl = priv->read(&regs->fdctrl);
1637 		reg_fdctrl &= ~(FIELD_PREP(FLEXCAN_FDCTRL_MBDSR1, 0x3) |
1638 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR0, 0x3));
1639 
1640 		if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
1641 			reg_fdctrl |=
1642 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR1,
1643 					   FLEXCAN_FDCTRL_MBDSR_64) |
1644 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR0,
1645 					   FLEXCAN_FDCTRL_MBDSR_64);
1646 		} else {
1647 			reg_fdctrl |=
1648 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR1,
1649 					   FLEXCAN_FDCTRL_MBDSR_8) |
1650 				FIELD_PREP(FLEXCAN_FDCTRL_MBDSR0,
1651 					   FLEXCAN_FDCTRL_MBDSR_8);
1652 		}
1653 
1654 		netdev_dbg(dev, "%s: writing fdctrl=0x%08x",
1655 			   __func__, reg_fdctrl);
1656 		priv->write(reg_fdctrl, &regs->fdctrl);
1657 	}
1658 
1659 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_USE_RX_MAILBOX) {
1660 		for (i = priv->offload.mb_first; i <= priv->offload.mb_last; i++) {
1661 			mb = flexcan_get_mb(priv, i);
1662 			priv->write(FLEXCAN_MB_CODE_RX_EMPTY,
1663 				    &mb->can_ctrl);
1664 		}
1665 	} else {
1666 		/* clear and invalidate unused mailboxes first */
1667 		for (i = FLEXCAN_TX_MB_RESERVED_RX_FIFO; i < priv->mb_count; i++) {
1668 			mb = flexcan_get_mb(priv, i);
1669 			priv->write(FLEXCAN_MB_CODE_RX_INACTIVE,
1670 				    &mb->can_ctrl);
1671 		}
1672 	}
1673 
1674 	/* Errata ERR005829: mark first TX mailbox as INACTIVE */
1675 	priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
1676 		    &priv->tx_mb_reserved->can_ctrl);
1677 
1678 	/* mark TX mailbox as INACTIVE */
1679 	priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
1680 		    &priv->tx_mb->can_ctrl);
1681 
1682 	/* acceptance mask/acceptance code (accept everything) */
1683 	priv->write(0x0, &regs->rxgmask);
1684 	priv->write(0x0, &regs->rx14mask);
1685 	priv->write(0x0, &regs->rx15mask);
1686 
1687 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_DISABLE_RXFG)
1688 		priv->write(0x0, &regs->rxfgmask);
1689 
1690 	/* clear acceptance filters */
1691 	for (i = 0; i < priv->mb_count; i++)
1692 		priv->write(0, &regs->rximr[i]);
1693 
1694 	/* On Vybrid, disable non-correctable errors interrupt and
1695 	 * freeze mode. It still can correct the correctable errors
1696 	 * when HW supports ECC.
1697 	 *
1698 	 * This also works around errata e5295 which generates false
1699 	 * positive memory errors and put the device in freeze mode.
1700 	 */
1701 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_DISABLE_MECR) {
1702 		/* Follow the protocol as described in "Detection
1703 		 * and Correction of Memory Errors" to write to
1704 		 * MECR register (step 1 - 5)
1705 		 *
1706 		 * 1. By default, CTRL2[ECRWRE] = 0, MECR[ECRWRDIS] = 1
1707 		 * 2. set CTRL2[ECRWRE]
1708 		 */
1709 		reg_ctrl2 = priv->read(&regs->ctrl2);
1710 		reg_ctrl2 |= FLEXCAN_CTRL2_ECRWRE;
1711 		priv->write(reg_ctrl2, &regs->ctrl2);
1712 
1713 		/* 3. clear MECR[ECRWRDIS] */
1714 		reg_mecr = priv->read(&regs->mecr);
1715 		reg_mecr &= ~FLEXCAN_MECR_ECRWRDIS;
1716 		priv->write(reg_mecr, &regs->mecr);
1717 
1718 		/* 4. all writes to MECR must keep MECR[ECRWRDIS] cleared */
1719 		reg_mecr &= ~(FLEXCAN_MECR_NCEFAFRZ | FLEXCAN_MECR_HANCEI_MSK |
1720 			      FLEXCAN_MECR_FANCEI_MSK);
1721 		priv->write(reg_mecr, &regs->mecr);
1722 
1723 		/* 5. after configuration done, lock MECR by either
1724 		 * setting MECR[ECRWRDIS] or clearing CTRL2[ECRWRE]
1725 		 */
1726 		reg_mecr |= FLEXCAN_MECR_ECRWRDIS;
1727 		priv->write(reg_mecr, &regs->mecr);
1728 
1729 		reg_ctrl2 &= ~FLEXCAN_CTRL2_ECRWRE;
1730 		priv->write(reg_ctrl2, &regs->ctrl2);
1731 	}
1732 
1733 	/* synchronize with the can bus */
1734 	err = flexcan_chip_unfreeze(priv);
1735 	if (err)
1736 		goto out_chip_disable;
1737 
1738 	priv->can.state = CAN_STATE_ERROR_ACTIVE;
1739 
1740 	/* print chip status */
1741 	netdev_dbg(dev, "%s: reading mcr=0x%08x ctrl=0x%08x\n", __func__,
1742 		   priv->read(&regs->mcr), priv->read(&regs->ctrl));
1743 
1744 	return 0;
1745 
1746  out_chip_disable:
1747 	flexcan_chip_disable(priv);
1748 	return err;
1749 }
1750 
1751 /* __flexcan_chip_stop
1752  *
1753  * this function is entered with clocks enabled
1754  */
__flexcan_chip_stop(struct net_device * dev,bool disable_on_error)1755 static int __flexcan_chip_stop(struct net_device *dev, bool disable_on_error)
1756 {
1757 	struct flexcan_priv *priv = netdev_priv(dev);
1758 	int err;
1759 
1760 	/* freeze + disable module */
1761 	err = flexcan_chip_freeze(priv);
1762 	if (err && !disable_on_error)
1763 		return err;
1764 	err = flexcan_chip_disable(priv);
1765 	if (err && !disable_on_error)
1766 		goto out_chip_unfreeze;
1767 
1768 	priv->can.state = CAN_STATE_STOPPED;
1769 
1770 	return 0;
1771 
1772  out_chip_unfreeze:
1773 	flexcan_chip_unfreeze(priv);
1774 
1775 	return err;
1776 }
1777 
flexcan_chip_stop_disable_on_error(struct net_device * dev)1778 static inline int flexcan_chip_stop_disable_on_error(struct net_device *dev)
1779 {
1780 	return __flexcan_chip_stop(dev, true);
1781 }
1782 
flexcan_chip_stop(struct net_device * dev)1783 static inline int flexcan_chip_stop(struct net_device *dev)
1784 {
1785 	return __flexcan_chip_stop(dev, false);
1786 }
1787 
flexcan_open(struct net_device * dev)1788 static int flexcan_open(struct net_device *dev)
1789 {
1790 	struct flexcan_priv *priv = netdev_priv(dev);
1791 	int err;
1792 
1793 	if ((priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) &&
1794 	    (priv->can.ctrlmode & CAN_CTRLMODE_FD)) {
1795 		netdev_err(dev, "Three Samples mode and CAN-FD mode can't be used together\n");
1796 		return -EINVAL;
1797 	}
1798 
1799 	err = pm_runtime_get_sync(priv->dev);
1800 	if (err < 0) {
1801 		pm_runtime_put_noidle(priv->dev);
1802 		return err;
1803 	}
1804 
1805 	err = open_candev(dev);
1806 	if (err)
1807 		goto out_runtime_put;
1808 
1809 	err = flexcan_transceiver_enable(priv);
1810 	if (err)
1811 		goto out_close;
1812 
1813 	err = flexcan_rx_offload_setup(dev);
1814 	if (err)
1815 		goto out_transceiver_disable;
1816 
1817 	err = flexcan_chip_start(dev);
1818 	if (err)
1819 		goto out_can_rx_offload_del;
1820 
1821 	can_rx_offload_enable(&priv->offload);
1822 
1823 	err = request_irq(dev->irq, flexcan_irq, IRQF_SHARED, dev->name, dev);
1824 	if (err)
1825 		goto out_can_rx_offload_disable;
1826 
1827 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_NR_IRQ_3) {
1828 		err = request_irq(priv->irq_boff,
1829 				  flexcan_irq, IRQF_SHARED, dev->name, dev);
1830 		if (err)
1831 			goto out_free_irq;
1832 
1833 		err = request_irq(priv->irq_err,
1834 				  flexcan_irq, IRQF_SHARED, dev->name, dev);
1835 		if (err)
1836 			goto out_free_irq_boff;
1837 	}
1838 
1839 	flexcan_chip_interrupts_enable(dev);
1840 
1841 	can_led_event(dev, CAN_LED_EVENT_OPEN);
1842 
1843 	netif_start_queue(dev);
1844 
1845 	return 0;
1846 
1847  out_free_irq_boff:
1848 	free_irq(priv->irq_boff, dev);
1849  out_free_irq:
1850 	free_irq(dev->irq, dev);
1851  out_can_rx_offload_disable:
1852 	can_rx_offload_disable(&priv->offload);
1853 	flexcan_chip_stop(dev);
1854  out_can_rx_offload_del:
1855 	can_rx_offload_del(&priv->offload);
1856  out_transceiver_disable:
1857 	flexcan_transceiver_disable(priv);
1858  out_close:
1859 	close_candev(dev);
1860  out_runtime_put:
1861 	pm_runtime_put(priv->dev);
1862 
1863 	return err;
1864 }
1865 
flexcan_close(struct net_device * dev)1866 static int flexcan_close(struct net_device *dev)
1867 {
1868 	struct flexcan_priv *priv = netdev_priv(dev);
1869 
1870 	netif_stop_queue(dev);
1871 	flexcan_chip_interrupts_disable(dev);
1872 
1873 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_NR_IRQ_3) {
1874 		free_irq(priv->irq_err, dev);
1875 		free_irq(priv->irq_boff, dev);
1876 	}
1877 
1878 	free_irq(dev->irq, dev);
1879 	can_rx_offload_disable(&priv->offload);
1880 	flexcan_chip_stop_disable_on_error(dev);
1881 
1882 	can_rx_offload_del(&priv->offload);
1883 	flexcan_transceiver_disable(priv);
1884 	close_candev(dev);
1885 
1886 	pm_runtime_put(priv->dev);
1887 
1888 	can_led_event(dev, CAN_LED_EVENT_STOP);
1889 
1890 	return 0;
1891 }
1892 
flexcan_set_mode(struct net_device * dev,enum can_mode mode)1893 static int flexcan_set_mode(struct net_device *dev, enum can_mode mode)
1894 {
1895 	int err;
1896 
1897 	switch (mode) {
1898 	case CAN_MODE_START:
1899 		err = flexcan_chip_start(dev);
1900 		if (err)
1901 			return err;
1902 
1903 		flexcan_chip_interrupts_enable(dev);
1904 
1905 		netif_wake_queue(dev);
1906 		break;
1907 
1908 	default:
1909 		return -EOPNOTSUPP;
1910 	}
1911 
1912 	return 0;
1913 }
1914 
1915 static const struct net_device_ops flexcan_netdev_ops = {
1916 	.ndo_open	= flexcan_open,
1917 	.ndo_stop	= flexcan_close,
1918 	.ndo_start_xmit	= flexcan_start_xmit,
1919 	.ndo_change_mtu = can_change_mtu,
1920 };
1921 
register_flexcandev(struct net_device * dev)1922 static int register_flexcandev(struct net_device *dev)
1923 {
1924 	struct flexcan_priv *priv = netdev_priv(dev);
1925 	struct flexcan_regs __iomem *regs = priv->regs;
1926 	u32 reg, err;
1927 
1928 	err = flexcan_clks_enable(priv);
1929 	if (err)
1930 		return err;
1931 
1932 	/* select "bus clock", chip must be disabled */
1933 	err = flexcan_chip_disable(priv);
1934 	if (err)
1935 		goto out_clks_disable;
1936 
1937 	reg = priv->read(&regs->ctrl);
1938 	if (priv->clk_src)
1939 		reg |= FLEXCAN_CTRL_CLK_SRC;
1940 	else
1941 		reg &= ~FLEXCAN_CTRL_CLK_SRC;
1942 	priv->write(reg, &regs->ctrl);
1943 
1944 	err = flexcan_chip_enable(priv);
1945 	if (err)
1946 		goto out_chip_disable;
1947 
1948 	/* set freeze, halt */
1949 	err = flexcan_chip_freeze(priv);
1950 	if (err)
1951 		goto out_chip_disable;
1952 
1953 	/* activate FIFO, restrict register access */
1954 	reg = priv->read(&regs->mcr);
1955 	reg |=  FLEXCAN_MCR_FEN | FLEXCAN_MCR_SUPV;
1956 	priv->write(reg, &regs->mcr);
1957 
1958 	/* Currently we only support newer versions of this core
1959 	 * featuring a RX hardware FIFO (although this driver doesn't
1960 	 * make use of it on some cores). Older cores, found on some
1961 	 * Coldfire derivates are not tested.
1962 	 */
1963 	reg = priv->read(&regs->mcr);
1964 	if (!(reg & FLEXCAN_MCR_FEN)) {
1965 		netdev_err(dev, "Could not enable RX FIFO, unsupported core\n");
1966 		err = -ENODEV;
1967 		goto out_chip_disable;
1968 	}
1969 
1970 	err = register_candev(dev);
1971 	if (err)
1972 		goto out_chip_disable;
1973 
1974 	/* Disable core and let pm_runtime_put() disable the clocks.
1975 	 * If CONFIG_PM is not enabled, the clocks will stay powered.
1976 	 */
1977 	flexcan_chip_disable(priv);
1978 	pm_runtime_put(priv->dev);
1979 
1980 	return 0;
1981 
1982  out_chip_disable:
1983 	flexcan_chip_disable(priv);
1984  out_clks_disable:
1985 	flexcan_clks_disable(priv);
1986 	return err;
1987 }
1988 
unregister_flexcandev(struct net_device * dev)1989 static void unregister_flexcandev(struct net_device *dev)
1990 {
1991 	unregister_candev(dev);
1992 }
1993 
flexcan_setup_stop_mode_gpr(struct platform_device * pdev)1994 static int flexcan_setup_stop_mode_gpr(struct platform_device *pdev)
1995 {
1996 	struct net_device *dev = platform_get_drvdata(pdev);
1997 	struct device_node *np = pdev->dev.of_node;
1998 	struct device_node *gpr_np;
1999 	struct flexcan_priv *priv;
2000 	phandle phandle;
2001 	u32 out_val[3];
2002 	int ret;
2003 
2004 	if (!np)
2005 		return -EINVAL;
2006 
2007 	/* stop mode property format is:
2008 	 * <&gpr req_gpr req_bit>.
2009 	 */
2010 	ret = of_property_read_u32_array(np, "fsl,stop-mode", out_val,
2011 					 ARRAY_SIZE(out_val));
2012 	if (ret) {
2013 		dev_dbg(&pdev->dev, "no stop-mode property\n");
2014 		return ret;
2015 	}
2016 	phandle = *out_val;
2017 
2018 	gpr_np = of_find_node_by_phandle(phandle);
2019 	if (!gpr_np) {
2020 		dev_dbg(&pdev->dev, "could not find gpr node by phandle\n");
2021 		return -ENODEV;
2022 	}
2023 
2024 	priv = netdev_priv(dev);
2025 	priv->stm.gpr = syscon_node_to_regmap(gpr_np);
2026 	if (IS_ERR(priv->stm.gpr)) {
2027 		dev_dbg(&pdev->dev, "could not find gpr regmap\n");
2028 		ret = PTR_ERR(priv->stm.gpr);
2029 		goto out_put_node;
2030 	}
2031 
2032 	priv->stm.req_gpr = out_val[1];
2033 	priv->stm.req_bit = out_val[2];
2034 
2035 	dev_dbg(&pdev->dev,
2036 		"gpr %s req_gpr=0x02%x req_bit=%u\n",
2037 		gpr_np->full_name, priv->stm.req_gpr, priv->stm.req_bit);
2038 
2039 	return 0;
2040 
2041 out_put_node:
2042 	of_node_put(gpr_np);
2043 	return ret;
2044 }
2045 
flexcan_setup_stop_mode_scfw(struct platform_device * pdev)2046 static int flexcan_setup_stop_mode_scfw(struct platform_device *pdev)
2047 {
2048 	struct net_device *dev = platform_get_drvdata(pdev);
2049 	struct flexcan_priv *priv;
2050 	u8 scu_idx;
2051 	int ret;
2052 
2053 	ret = of_property_read_u8(pdev->dev.of_node, "fsl,scu-index", &scu_idx);
2054 	if (ret < 0) {
2055 		dev_dbg(&pdev->dev, "failed to get scu index\n");
2056 		return ret;
2057 	}
2058 
2059 	priv = netdev_priv(dev);
2060 	priv->scu_idx = scu_idx;
2061 
2062 	/* this function could be deferred probe, return -EPROBE_DEFER */
2063 	return imx_scu_get_handle(&priv->sc_ipc_handle);
2064 }
2065 
2066 /* flexcan_setup_stop_mode - Setup stop mode for wakeup
2067  *
2068  * Return: = 0 setup stop mode successfully or doesn't support this feature
2069  *         < 0 fail to setup stop mode (could be deferred probe)
2070  */
flexcan_setup_stop_mode(struct platform_device * pdev)2071 static int flexcan_setup_stop_mode(struct platform_device *pdev)
2072 {
2073 	struct net_device *dev = platform_get_drvdata(pdev);
2074 	struct flexcan_priv *priv;
2075 	int ret;
2076 
2077 	priv = netdev_priv(dev);
2078 
2079 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW)
2080 		ret = flexcan_setup_stop_mode_scfw(pdev);
2081 	else if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR)
2082 		ret = flexcan_setup_stop_mode_gpr(pdev);
2083 	else
2084 		/* return 0 directly if doesn't support stop mode feature */
2085 		return 0;
2086 
2087 	if (ret)
2088 		return ret;
2089 
2090 	device_set_wakeup_capable(&pdev->dev, true);
2091 
2092 	if (of_property_read_bool(pdev->dev.of_node, "wakeup-source"))
2093 		device_set_wakeup_enable(&pdev->dev, true);
2094 
2095 	return 0;
2096 }
2097 
2098 static const struct of_device_id flexcan_of_match[] = {
2099 	{ .compatible = "fsl,imx8qm-flexcan", .data = &fsl_imx8qm_devtype_data, },
2100 	{ .compatible = "fsl,imx8mp-flexcan", .data = &fsl_imx8mp_devtype_data, },
2101 	{ .compatible = "fsl,imx6q-flexcan", .data = &fsl_imx6q_devtype_data, },
2102 	{ .compatible = "fsl,imx28-flexcan", .data = &fsl_imx28_devtype_data, },
2103 	{ .compatible = "fsl,imx53-flexcan", .data = &fsl_imx25_devtype_data, },
2104 	{ .compatible = "fsl,imx35-flexcan", .data = &fsl_imx25_devtype_data, },
2105 	{ .compatible = "fsl,imx25-flexcan", .data = &fsl_imx25_devtype_data, },
2106 	{ .compatible = "fsl,p1010-flexcan", .data = &fsl_p1010_devtype_data, },
2107 	{ .compatible = "fsl,vf610-flexcan", .data = &fsl_vf610_devtype_data, },
2108 	{ .compatible = "fsl,ls1021ar2-flexcan", .data = &fsl_ls1021a_r2_devtype_data, },
2109 	{ .compatible = "fsl,lx2160ar1-flexcan", .data = &fsl_lx2160a_r1_devtype_data, },
2110 	{ /* sentinel */ },
2111 };
2112 MODULE_DEVICE_TABLE(of, flexcan_of_match);
2113 
2114 static const struct platform_device_id flexcan_id_table[] = {
2115 	{
2116 		.name = "flexcan-mcf5441x",
2117 		.driver_data = (kernel_ulong_t)&fsl_mcf5441x_devtype_data,
2118 	}, {
2119 		/* sentinel */
2120 	},
2121 };
2122 MODULE_DEVICE_TABLE(platform, flexcan_id_table);
2123 
flexcan_probe(struct platform_device * pdev)2124 static int flexcan_probe(struct platform_device *pdev)
2125 {
2126 	const struct of_device_id *of_id;
2127 	const struct flexcan_devtype_data *devtype_data;
2128 	struct net_device *dev;
2129 	struct flexcan_priv *priv;
2130 	struct regulator *reg_xceiver;
2131 	struct clk *clk_ipg = NULL, *clk_per = NULL;
2132 	struct flexcan_regs __iomem *regs;
2133 	struct flexcan_platform_data *pdata;
2134 	int err, irq;
2135 	u8 clk_src = 1;
2136 	u32 clock_freq = 0;
2137 
2138 	reg_xceiver = devm_regulator_get_optional(&pdev->dev, "xceiver");
2139 	if (PTR_ERR(reg_xceiver) == -EPROBE_DEFER)
2140 		return -EPROBE_DEFER;
2141 	else if (PTR_ERR(reg_xceiver) == -ENODEV)
2142 		reg_xceiver = NULL;
2143 	else if (IS_ERR(reg_xceiver))
2144 		return PTR_ERR(reg_xceiver);
2145 
2146 	if (pdev->dev.of_node) {
2147 		of_property_read_u32(pdev->dev.of_node,
2148 				     "clock-frequency", &clock_freq);
2149 		of_property_read_u8(pdev->dev.of_node,
2150 				    "fsl,clk-source", &clk_src);
2151 	} else {
2152 		pdata = dev_get_platdata(&pdev->dev);
2153 		if (pdata) {
2154 			clock_freq = pdata->clock_frequency;
2155 			clk_src = pdata->clk_src;
2156 		}
2157 	}
2158 
2159 	if (!clock_freq) {
2160 		clk_ipg = devm_clk_get(&pdev->dev, "ipg");
2161 		if (IS_ERR(clk_ipg)) {
2162 			dev_err(&pdev->dev, "no ipg clock defined\n");
2163 			return PTR_ERR(clk_ipg);
2164 		}
2165 
2166 		clk_per = devm_clk_get(&pdev->dev, "per");
2167 		if (IS_ERR(clk_per)) {
2168 			dev_err(&pdev->dev, "no per clock defined\n");
2169 			return PTR_ERR(clk_per);
2170 		}
2171 		clock_freq = clk_get_rate(clk_per);
2172 	}
2173 
2174 	irq = platform_get_irq(pdev, 0);
2175 	if (irq <= 0)
2176 		return -ENODEV;
2177 
2178 	regs = devm_platform_ioremap_resource(pdev, 0);
2179 	if (IS_ERR(regs))
2180 		return PTR_ERR(regs);
2181 
2182 	of_id = of_match_device(flexcan_of_match, &pdev->dev);
2183 	if (of_id)
2184 		devtype_data = of_id->data;
2185 	else if (platform_get_device_id(pdev)->driver_data)
2186 		devtype_data = (struct flexcan_devtype_data *)
2187 			platform_get_device_id(pdev)->driver_data;
2188 	else
2189 		return -ENODEV;
2190 
2191 	if ((devtype_data->quirks & FLEXCAN_QUIRK_SUPPORT_FD) &&
2192 	    !((devtype_data->quirks &
2193 	       (FLEXCAN_QUIRK_USE_RX_MAILBOX |
2194 		FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX |
2195 		FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX_RTR |
2196 		FLEXCAN_QUIRK_SUPPPORT_RX_FIFO)) ==
2197 	      (FLEXCAN_QUIRK_USE_RX_MAILBOX |
2198 	       FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX |
2199 	       FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX_RTR))) {
2200 		dev_err(&pdev->dev, "CAN-FD mode doesn't work in RX-FIFO mode!\n");
2201 		return -EINVAL;
2202 	}
2203 
2204 	if ((devtype_data->quirks &
2205 	     (FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX |
2206 	      FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX_RTR)) ==
2207 	    FLEXCAN_QUIRK_SUPPPORT_RX_MAILBOX_RTR) {
2208 		dev_err(&pdev->dev,
2209 			"Quirks (0x%08x) inconsistent: RX_MAILBOX_RX supported but not RX_MAILBOX\n",
2210 			devtype_data->quirks);
2211 		return -EINVAL;
2212 	}
2213 
2214 	dev = alloc_candev(sizeof(struct flexcan_priv), 1);
2215 	if (!dev)
2216 		return -ENOMEM;
2217 
2218 	platform_set_drvdata(pdev, dev);
2219 	SET_NETDEV_DEV(dev, &pdev->dev);
2220 
2221 	dev->netdev_ops = &flexcan_netdev_ops;
2222 	dev->irq = irq;
2223 	dev->flags |= IFF_ECHO;
2224 
2225 	priv = netdev_priv(dev);
2226 	priv->devtype_data = *devtype_data;
2227 
2228 	if (of_property_read_bool(pdev->dev.of_node, "big-endian") ||
2229 	    priv->devtype_data.quirks & FLEXCAN_QUIRK_DEFAULT_BIG_ENDIAN) {
2230 		priv->read = flexcan_read_be;
2231 		priv->write = flexcan_write_be;
2232 	} else {
2233 		priv->read = flexcan_read_le;
2234 		priv->write = flexcan_write_le;
2235 	}
2236 
2237 	priv->dev = &pdev->dev;
2238 	priv->can.clock.freq = clock_freq;
2239 	priv->can.do_set_mode = flexcan_set_mode;
2240 	priv->can.do_get_berr_counter = flexcan_get_berr_counter;
2241 	priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
2242 		CAN_CTRLMODE_LISTENONLY	| CAN_CTRLMODE_3_SAMPLES |
2243 		CAN_CTRLMODE_BERR_REPORTING;
2244 	priv->regs = regs;
2245 	priv->clk_ipg = clk_ipg;
2246 	priv->clk_per = clk_per;
2247 	priv->clk_src = clk_src;
2248 	priv->reg_xceiver = reg_xceiver;
2249 
2250 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_NR_IRQ_3) {
2251 		priv->irq_boff = platform_get_irq(pdev, 1);
2252 		if (priv->irq_boff <= 0) {
2253 			err = -ENODEV;
2254 			goto failed_platform_get_irq;
2255 		}
2256 		priv->irq_err = platform_get_irq(pdev, 2);
2257 		if (priv->irq_err <= 0) {
2258 			err = -ENODEV;
2259 			goto failed_platform_get_irq;
2260 		}
2261 	}
2262 
2263 	if (priv->devtype_data.quirks & FLEXCAN_QUIRK_SUPPORT_FD) {
2264 		priv->can.ctrlmode_supported |= CAN_CTRLMODE_FD |
2265 			CAN_CTRLMODE_FD_NON_ISO;
2266 		priv->can.bittiming_const = &flexcan_fd_bittiming_const;
2267 		priv->can.data_bittiming_const =
2268 			&flexcan_fd_data_bittiming_const;
2269 	} else {
2270 		priv->can.bittiming_const = &flexcan_bittiming_const;
2271 	}
2272 
2273 	pm_runtime_get_noresume(&pdev->dev);
2274 	pm_runtime_set_active(&pdev->dev);
2275 	pm_runtime_enable(&pdev->dev);
2276 
2277 	err = register_flexcandev(dev);
2278 	if (err) {
2279 		dev_err(&pdev->dev, "registering netdev failed\n");
2280 		goto failed_register;
2281 	}
2282 
2283 	err = flexcan_setup_stop_mode(pdev);
2284 	if (err < 0) {
2285 		if (err != -EPROBE_DEFER)
2286 			dev_err(&pdev->dev, "setup stop mode failed\n");
2287 		goto failed_setup_stop_mode;
2288 	}
2289 
2290 	of_can_transceiver(dev);
2291 	devm_can_led_init(dev);
2292 
2293 	return 0;
2294 
2295  failed_setup_stop_mode:
2296 	unregister_flexcandev(dev);
2297  failed_register:
2298 	pm_runtime_put_noidle(&pdev->dev);
2299 	pm_runtime_disable(&pdev->dev);
2300  failed_platform_get_irq:
2301 	free_candev(dev);
2302 	return err;
2303 }
2304 
flexcan_remove(struct platform_device * pdev)2305 static int flexcan_remove(struct platform_device *pdev)
2306 {
2307 	struct net_device *dev = platform_get_drvdata(pdev);
2308 
2309 	device_set_wakeup_enable(&pdev->dev, false);
2310 	device_set_wakeup_capable(&pdev->dev, false);
2311 	unregister_flexcandev(dev);
2312 	pm_runtime_disable(&pdev->dev);
2313 	free_candev(dev);
2314 
2315 	return 0;
2316 }
2317 
flexcan_suspend(struct device * device)2318 static int __maybe_unused flexcan_suspend(struct device *device)
2319 {
2320 	struct net_device *dev = dev_get_drvdata(device);
2321 	struct flexcan_priv *priv = netdev_priv(dev);
2322 	int err;
2323 
2324 	if (netif_running(dev)) {
2325 		/* if wakeup is enabled, enter stop mode
2326 		 * else enter disabled mode.
2327 		 */
2328 		if (device_may_wakeup(device)) {
2329 			enable_irq_wake(dev->irq);
2330 			err = flexcan_enter_stop_mode(priv);
2331 			if (err)
2332 				return err;
2333 		} else {
2334 			err = flexcan_chip_stop(dev);
2335 			if (err)
2336 				return err;
2337 
2338 			flexcan_chip_interrupts_disable(dev);
2339 
2340 			err = pinctrl_pm_select_sleep_state(device);
2341 			if (err)
2342 				return err;
2343 		}
2344 		netif_stop_queue(dev);
2345 		netif_device_detach(dev);
2346 	}
2347 	priv->can.state = CAN_STATE_SLEEPING;
2348 
2349 	return 0;
2350 }
2351 
flexcan_resume(struct device * device)2352 static int __maybe_unused flexcan_resume(struct device *device)
2353 {
2354 	struct net_device *dev = dev_get_drvdata(device);
2355 	struct flexcan_priv *priv = netdev_priv(dev);
2356 	int err;
2357 
2358 	priv->can.state = CAN_STATE_ERROR_ACTIVE;
2359 	if (netif_running(dev)) {
2360 		netif_device_attach(dev);
2361 		netif_start_queue(dev);
2362 		if (device_may_wakeup(device)) {
2363 			disable_irq_wake(dev->irq);
2364 			err = flexcan_exit_stop_mode(priv);
2365 			if (err)
2366 				return err;
2367 		} else {
2368 			err = pinctrl_pm_select_default_state(device);
2369 			if (err)
2370 				return err;
2371 
2372 			err = flexcan_chip_start(dev);
2373 			if (err)
2374 				return err;
2375 
2376 			flexcan_chip_interrupts_enable(dev);
2377 		}
2378 	}
2379 
2380 	return 0;
2381 }
2382 
flexcan_runtime_suspend(struct device * device)2383 static int __maybe_unused flexcan_runtime_suspend(struct device *device)
2384 {
2385 	struct net_device *dev = dev_get_drvdata(device);
2386 	struct flexcan_priv *priv = netdev_priv(dev);
2387 
2388 	flexcan_clks_disable(priv);
2389 
2390 	return 0;
2391 }
2392 
flexcan_runtime_resume(struct device * device)2393 static int __maybe_unused flexcan_runtime_resume(struct device *device)
2394 {
2395 	struct net_device *dev = dev_get_drvdata(device);
2396 	struct flexcan_priv *priv = netdev_priv(dev);
2397 
2398 	return flexcan_clks_enable(priv);
2399 }
2400 
flexcan_noirq_suspend(struct device * device)2401 static int __maybe_unused flexcan_noirq_suspend(struct device *device)
2402 {
2403 	struct net_device *dev = dev_get_drvdata(device);
2404 	struct flexcan_priv *priv = netdev_priv(dev);
2405 
2406 	if (netif_running(dev)) {
2407 		int err;
2408 
2409 		if (device_may_wakeup(device))
2410 			flexcan_enable_wakeup_irq(priv, true);
2411 
2412 		err = pm_runtime_force_suspend(device);
2413 		if (err)
2414 			return err;
2415 	}
2416 
2417 	return 0;
2418 }
2419 
flexcan_noirq_resume(struct device * device)2420 static int __maybe_unused flexcan_noirq_resume(struct device *device)
2421 {
2422 	struct net_device *dev = dev_get_drvdata(device);
2423 	struct flexcan_priv *priv = netdev_priv(dev);
2424 
2425 	if (netif_running(dev)) {
2426 		int err;
2427 
2428 		err = pm_runtime_force_resume(device);
2429 		if (err)
2430 			return err;
2431 
2432 		if (device_may_wakeup(device))
2433 			flexcan_enable_wakeup_irq(priv, false);
2434 	}
2435 
2436 	return 0;
2437 }
2438 
2439 static const struct dev_pm_ops flexcan_pm_ops = {
2440 	SET_SYSTEM_SLEEP_PM_OPS(flexcan_suspend, flexcan_resume)
2441 	SET_RUNTIME_PM_OPS(flexcan_runtime_suspend, flexcan_runtime_resume, NULL)
2442 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(flexcan_noirq_suspend, flexcan_noirq_resume)
2443 };
2444 
2445 static struct platform_driver flexcan_driver = {
2446 	.driver = {
2447 		.name = DRV_NAME,
2448 		.pm = &flexcan_pm_ops,
2449 		.of_match_table = flexcan_of_match,
2450 	},
2451 	.probe = flexcan_probe,
2452 	.remove = flexcan_remove,
2453 	.id_table = flexcan_id_table,
2454 };
2455 
2456 module_platform_driver(flexcan_driver);
2457 
2458 MODULE_AUTHOR("Sascha Hauer <kernel@pengutronix.de>, "
2459 	      "Marc Kleine-Budde <kernel@pengutronix.de>");
2460 MODULE_LICENSE("GPL v2");
2461 MODULE_DESCRIPTION("CAN port driver for flexcan based chip");
2462