xref: /openbmc/linux/drivers/net/can/rcar/rcar_canfd.c (revision a5961bed)
1 // SPDX-License-Identifier: GPL-2.0+
2 /* Renesas R-Car CAN FD device driver
3  *
4  * Copyright (C) 2015 Renesas Electronics Corp.
5  */
6 
7 /* The R-Car CAN FD controller can operate in either one of the below two modes
8  *  - CAN FD only mode
9  *  - Classical CAN (CAN 2.0) only mode
10  *
11  * This driver puts the controller in CAN FD only mode by default. In this
12  * mode, the controller acts as a CAN FD node that can also interoperate with
13  * CAN 2.0 nodes.
14  *
15  * To switch the controller to Classical CAN (CAN 2.0) only mode, add
16  * "renesas,no-can-fd" optional property to the device tree node. A h/w reset is
17  * also required to switch modes.
18  *
19  * Note: The h/w manual register naming convention is clumsy and not acceptable
20  * to use as it is in the driver. However, those names are added as comments
21  * wherever it is modified to a readable name.
22  */
23 
24 #include <linux/bitmap.h>
25 #include <linux/bitops.h>
26 #include <linux/can/dev.h>
27 #include <linux/clk.h>
28 #include <linux/errno.h>
29 #include <linux/ethtool.h>
30 #include <linux/interrupt.h>
31 #include <linux/iopoll.h>
32 #include <linux/kernel.h>
33 #include <linux/module.h>
34 #include <linux/moduleparam.h>
35 #include <linux/netdevice.h>
36 #include <linux/of.h>
37 #include <linux/of_device.h>
38 #include <linux/phy/phy.h>
39 #include <linux/platform_device.h>
40 #include <linux/reset.h>
41 #include <linux/types.h>
42 
43 #define RCANFD_DRV_NAME			"rcar_canfd"
44 
45 /* Global register bits */
46 
47 /* RSCFDnCFDGRMCFG */
48 #define RCANFD_GRMCFG_RCMC		BIT(0)
49 
50 /* RSCFDnCFDGCFG / RSCFDnGCFG */
51 #define RCANFD_GCFG_EEFE		BIT(6)
52 #define RCANFD_GCFG_CMPOC		BIT(5)	/* CAN FD only */
53 #define RCANFD_GCFG_DCS			BIT(4)
54 #define RCANFD_GCFG_DCE			BIT(1)
55 #define RCANFD_GCFG_TPRI		BIT(0)
56 
57 /* RSCFDnCFDGCTR / RSCFDnGCTR */
58 #define RCANFD_GCTR_TSRST		BIT(16)
59 #define RCANFD_GCTR_CFMPOFIE		BIT(11)	/* CAN FD only */
60 #define RCANFD_GCTR_THLEIE		BIT(10)
61 #define RCANFD_GCTR_MEIE		BIT(9)
62 #define RCANFD_GCTR_DEIE		BIT(8)
63 #define RCANFD_GCTR_GSLPR		BIT(2)
64 #define RCANFD_GCTR_GMDC_MASK		(0x3)
65 #define RCANFD_GCTR_GMDC_GOPM		(0x0)
66 #define RCANFD_GCTR_GMDC_GRESET		(0x1)
67 #define RCANFD_GCTR_GMDC_GTEST		(0x2)
68 
69 /* RSCFDnCFDGSTS / RSCFDnGSTS */
70 #define RCANFD_GSTS_GRAMINIT		BIT(3)
71 #define RCANFD_GSTS_GSLPSTS		BIT(2)
72 #define RCANFD_GSTS_GHLTSTS		BIT(1)
73 #define RCANFD_GSTS_GRSTSTS		BIT(0)
74 /* Non-operational status */
75 #define RCANFD_GSTS_GNOPM		(BIT(0) | BIT(1) | BIT(2) | BIT(3))
76 
77 /* RSCFDnCFDGERFL / RSCFDnGERFL */
78 #define RCANFD_GERFL_EEF0_7		GENMASK(23, 16)
79 #define RCANFD_GERFL_EEF(ch)		BIT(16 + (ch))
80 #define RCANFD_GERFL_CMPOF		BIT(3)	/* CAN FD only */
81 #define RCANFD_GERFL_THLES		BIT(2)
82 #define RCANFD_GERFL_MES		BIT(1)
83 #define RCANFD_GERFL_DEF		BIT(0)
84 
85 #define RCANFD_GERFL_ERR(gpriv, x) \
86 	((x) & (reg_gen4(gpriv, RCANFD_GERFL_EEF0_7, \
87 			 RCANFD_GERFL_EEF(0) | RCANFD_GERFL_EEF(1)) | \
88 		RCANFD_GERFL_MES | \
89 		((gpriv)->fdmode ? RCANFD_GERFL_CMPOF : 0)))
90 
91 /* AFL Rx rules registers */
92 
93 /* RSCFDnCFDGAFLCFG0 / RSCFDnGAFLCFG0 */
94 #define RCANFD_GAFLCFG_SETRNC(gpriv, n, x) \
95 	(((x) & reg_gen4(gpriv, 0x1ff, 0xff)) << \
96 	 (reg_gen4(gpriv, 16, 24) - ((n) & 1) * reg_gen4(gpriv, 16, 8)))
97 
98 #define RCANFD_GAFLCFG_GETRNC(gpriv, n, x) \
99 	(((x) >> (reg_gen4(gpriv, 16, 24) - ((n) & 1) * reg_gen4(gpriv, 16, 8))) & \
100 	 reg_gen4(gpriv, 0x1ff, 0xff))
101 
102 /* RSCFDnCFDGAFLECTR / RSCFDnGAFLECTR */
103 #define RCANFD_GAFLECTR_AFLDAE		BIT(8)
104 #define RCANFD_GAFLECTR_AFLPN(gpriv, x)	((x) & reg_gen4(gpriv, 0x7f, 0x1f))
105 
106 /* RSCFDnCFDGAFLIDj / RSCFDnGAFLIDj */
107 #define RCANFD_GAFLID_GAFLLB		BIT(29)
108 
109 /* RSCFDnCFDGAFLP1_j / RSCFDnGAFLP1_j */
110 #define RCANFD_GAFLP1_GAFLFDP(x)	(1 << (x))
111 
112 /* Channel register bits */
113 
114 /* RSCFDnCmCFG - Classical CAN only */
115 #define RCANFD_CFG_SJW(x)		(((x) & 0x3) << 24)
116 #define RCANFD_CFG_TSEG2(x)		(((x) & 0x7) << 20)
117 #define RCANFD_CFG_TSEG1(x)		(((x) & 0xf) << 16)
118 #define RCANFD_CFG_BRP(x)		(((x) & 0x3ff) << 0)
119 
120 /* RSCFDnCFDCmNCFG - CAN FD only */
121 #define RCANFD_NCFG_NTSEG2(gpriv, x) \
122 	(((x) & reg_gen4(gpriv, 0x7f, 0x1f)) << reg_gen4(gpriv, 25, 24))
123 
124 #define RCANFD_NCFG_NTSEG1(gpriv, x) \
125 	(((x) & reg_gen4(gpriv, 0xff, 0x7f)) << reg_gen4(gpriv, 17, 16))
126 
127 #define RCANFD_NCFG_NSJW(gpriv, x) \
128 	(((x) & reg_gen4(gpriv, 0x7f, 0x1f)) << reg_gen4(gpriv, 10, 11))
129 
130 #define RCANFD_NCFG_NBRP(x)		(((x) & 0x3ff) << 0)
131 
132 /* RSCFDnCFDCmCTR / RSCFDnCmCTR */
133 #define RCANFD_CCTR_CTME		BIT(24)
134 #define RCANFD_CCTR_ERRD		BIT(23)
135 #define RCANFD_CCTR_BOM_MASK		(0x3 << 21)
136 #define RCANFD_CCTR_BOM_ISO		(0x0 << 21)
137 #define RCANFD_CCTR_BOM_BENTRY		(0x1 << 21)
138 #define RCANFD_CCTR_BOM_BEND		(0x2 << 21)
139 #define RCANFD_CCTR_TDCVFIE		BIT(19)
140 #define RCANFD_CCTR_SOCOIE		BIT(18)
141 #define RCANFD_CCTR_EOCOIE		BIT(17)
142 #define RCANFD_CCTR_TAIE		BIT(16)
143 #define RCANFD_CCTR_ALIE		BIT(15)
144 #define RCANFD_CCTR_BLIE		BIT(14)
145 #define RCANFD_CCTR_OLIE		BIT(13)
146 #define RCANFD_CCTR_BORIE		BIT(12)
147 #define RCANFD_CCTR_BOEIE		BIT(11)
148 #define RCANFD_CCTR_EPIE		BIT(10)
149 #define RCANFD_CCTR_EWIE		BIT(9)
150 #define RCANFD_CCTR_BEIE		BIT(8)
151 #define RCANFD_CCTR_CSLPR		BIT(2)
152 #define RCANFD_CCTR_CHMDC_MASK		(0x3)
153 #define RCANFD_CCTR_CHDMC_COPM		(0x0)
154 #define RCANFD_CCTR_CHDMC_CRESET	(0x1)
155 #define RCANFD_CCTR_CHDMC_CHLT		(0x2)
156 
157 /* RSCFDnCFDCmSTS / RSCFDnCmSTS */
158 #define RCANFD_CSTS_COMSTS		BIT(7)
159 #define RCANFD_CSTS_RECSTS		BIT(6)
160 #define RCANFD_CSTS_TRMSTS		BIT(5)
161 #define RCANFD_CSTS_BOSTS		BIT(4)
162 #define RCANFD_CSTS_EPSTS		BIT(3)
163 #define RCANFD_CSTS_SLPSTS		BIT(2)
164 #define RCANFD_CSTS_HLTSTS		BIT(1)
165 #define RCANFD_CSTS_CRSTSTS		BIT(0)
166 
167 #define RCANFD_CSTS_TECCNT(x)		(((x) >> 24) & 0xff)
168 #define RCANFD_CSTS_RECCNT(x)		(((x) >> 16) & 0xff)
169 
170 /* RSCFDnCFDCmERFL / RSCFDnCmERFL */
171 #define RCANFD_CERFL_ADERR		BIT(14)
172 #define RCANFD_CERFL_B0ERR		BIT(13)
173 #define RCANFD_CERFL_B1ERR		BIT(12)
174 #define RCANFD_CERFL_CERR		BIT(11)
175 #define RCANFD_CERFL_AERR		BIT(10)
176 #define RCANFD_CERFL_FERR		BIT(9)
177 #define RCANFD_CERFL_SERR		BIT(8)
178 #define RCANFD_CERFL_ALF		BIT(7)
179 #define RCANFD_CERFL_BLF		BIT(6)
180 #define RCANFD_CERFL_OVLF		BIT(5)
181 #define RCANFD_CERFL_BORF		BIT(4)
182 #define RCANFD_CERFL_BOEF		BIT(3)
183 #define RCANFD_CERFL_EPF		BIT(2)
184 #define RCANFD_CERFL_EWF		BIT(1)
185 #define RCANFD_CERFL_BEF		BIT(0)
186 
187 #define RCANFD_CERFL_ERR(x)		((x) & (0x7fff)) /* above bits 14:0 */
188 
189 /* RSCFDnCFDCmDCFG */
190 #define RCANFD_DCFG_DSJW(gpriv, x)	(((x) & reg_gen4(gpriv, 0xf, 0x7)) << 24)
191 
192 #define RCANFD_DCFG_DTSEG2(gpriv, x) \
193 	(((x) & reg_gen4(gpriv, 0x0f, 0x7)) << reg_gen4(gpriv, 16, 20))
194 
195 #define RCANFD_DCFG_DTSEG1(gpriv, x) \
196 	(((x) & reg_gen4(gpriv, 0x1f, 0xf)) << reg_gen4(gpriv, 8, 16))
197 
198 #define RCANFD_DCFG_DBRP(x)		(((x) & 0xff) << 0)
199 
200 /* RSCFDnCFDCmFDCFG */
201 #define RCANFD_GEN4_FDCFG_CLOE		BIT(30)
202 #define RCANFD_GEN4_FDCFG_FDOE		BIT(28)
203 #define RCANFD_FDCFG_TDCE		BIT(9)
204 #define RCANFD_FDCFG_TDCOC		BIT(8)
205 #define RCANFD_FDCFG_TDCO(x)		(((x) & 0x7f) >> 16)
206 
207 /* RSCFDnCFDRFCCx */
208 #define RCANFD_RFCC_RFIM		BIT(12)
209 #define RCANFD_RFCC_RFDC(x)		(((x) & 0x7) << 8)
210 #define RCANFD_RFCC_RFPLS(x)		(((x) & 0x7) << 4)
211 #define RCANFD_RFCC_RFIE		BIT(1)
212 #define RCANFD_RFCC_RFE			BIT(0)
213 
214 /* RSCFDnCFDRFSTSx */
215 #define RCANFD_RFSTS_RFIF		BIT(3)
216 #define RCANFD_RFSTS_RFMLT		BIT(2)
217 #define RCANFD_RFSTS_RFFLL		BIT(1)
218 #define RCANFD_RFSTS_RFEMP		BIT(0)
219 
220 /* RSCFDnCFDRFIDx */
221 #define RCANFD_RFID_RFIDE		BIT(31)
222 #define RCANFD_RFID_RFRTR		BIT(30)
223 
224 /* RSCFDnCFDRFPTRx */
225 #define RCANFD_RFPTR_RFDLC(x)		(((x) >> 28) & 0xf)
226 #define RCANFD_RFPTR_RFPTR(x)		(((x) >> 16) & 0xfff)
227 #define RCANFD_RFPTR_RFTS(x)		(((x) >> 0) & 0xffff)
228 
229 /* RSCFDnCFDRFFDSTSx */
230 #define RCANFD_RFFDSTS_RFFDF		BIT(2)
231 #define RCANFD_RFFDSTS_RFBRS		BIT(1)
232 #define RCANFD_RFFDSTS_RFESI		BIT(0)
233 
234 /* Common FIFO bits */
235 
236 /* RSCFDnCFDCFCCk */
237 #define RCANFD_CFCC_CFTML(gpriv, x)	\
238 	(((x) & reg_gen4(gpriv, 0x1f, 0xf)) << reg_gen4(gpriv, 16, 20))
239 #define RCANFD_CFCC_CFM(gpriv, x)	(((x) & 0x3) << reg_gen4(gpriv,  8, 16))
240 #define RCANFD_CFCC_CFIM		BIT(12)
241 #define RCANFD_CFCC_CFDC(gpriv, x)	(((x) & 0x7) << reg_gen4(gpriv, 21,  8))
242 #define RCANFD_CFCC_CFPLS(x)		(((x) & 0x7) << 4)
243 #define RCANFD_CFCC_CFTXIE		BIT(2)
244 #define RCANFD_CFCC_CFE			BIT(0)
245 
246 /* RSCFDnCFDCFSTSk */
247 #define RCANFD_CFSTS_CFMC(x)		(((x) >> 8) & 0xff)
248 #define RCANFD_CFSTS_CFTXIF		BIT(4)
249 #define RCANFD_CFSTS_CFMLT		BIT(2)
250 #define RCANFD_CFSTS_CFFLL		BIT(1)
251 #define RCANFD_CFSTS_CFEMP		BIT(0)
252 
253 /* RSCFDnCFDCFIDk */
254 #define RCANFD_CFID_CFIDE		BIT(31)
255 #define RCANFD_CFID_CFRTR		BIT(30)
256 #define RCANFD_CFID_CFID_MASK(x)	((x) & 0x1fffffff)
257 
258 /* RSCFDnCFDCFPTRk */
259 #define RCANFD_CFPTR_CFDLC(x)		(((x) & 0xf) << 28)
260 #define RCANFD_CFPTR_CFPTR(x)		(((x) & 0xfff) << 16)
261 #define RCANFD_CFPTR_CFTS(x)		(((x) & 0xff) << 0)
262 
263 /* RSCFDnCFDCFFDCSTSk */
264 #define RCANFD_CFFDCSTS_CFFDF		BIT(2)
265 #define RCANFD_CFFDCSTS_CFBRS		BIT(1)
266 #define RCANFD_CFFDCSTS_CFESI		BIT(0)
267 
268 /* This controller supports either Classical CAN only mode or CAN FD only mode.
269  * These modes are supported in two separate set of register maps & names.
270  * However, some of the register offsets are common for both modes. Those
271  * offsets are listed below as Common registers.
272  *
273  * The CAN FD only mode specific registers & Classical CAN only mode specific
274  * registers are listed separately. Their register names starts with
275  * RCANFD_F_xxx & RCANFD_C_xxx respectively.
276  */
277 
278 /* Common registers */
279 
280 /* RSCFDnCFDCmNCFG / RSCFDnCmCFG */
281 #define RCANFD_CCFG(m)			(0x0000 + (0x10 * (m)))
282 /* RSCFDnCFDCmCTR / RSCFDnCmCTR */
283 #define RCANFD_CCTR(m)			(0x0004 + (0x10 * (m)))
284 /* RSCFDnCFDCmSTS / RSCFDnCmSTS */
285 #define RCANFD_CSTS(m)			(0x0008 + (0x10 * (m)))
286 /* RSCFDnCFDCmERFL / RSCFDnCmERFL */
287 #define RCANFD_CERFL(m)			(0x000C + (0x10 * (m)))
288 
289 /* RSCFDnCFDGCFG / RSCFDnGCFG */
290 #define RCANFD_GCFG			(0x0084)
291 /* RSCFDnCFDGCTR / RSCFDnGCTR */
292 #define RCANFD_GCTR			(0x0088)
293 /* RSCFDnCFDGCTS / RSCFDnGCTS */
294 #define RCANFD_GSTS			(0x008c)
295 /* RSCFDnCFDGERFL / RSCFDnGERFL */
296 #define RCANFD_GERFL			(0x0090)
297 /* RSCFDnCFDGTSC / RSCFDnGTSC */
298 #define RCANFD_GTSC			(0x0094)
299 /* RSCFDnCFDGAFLECTR / RSCFDnGAFLECTR */
300 #define RCANFD_GAFLECTR			(0x0098)
301 /* RSCFDnCFDGAFLCFG / RSCFDnGAFLCFG */
302 #define RCANFD_GAFLCFG(ch)		(0x009c + (0x04 * ((ch) / 2)))
303 /* RSCFDnCFDRMNB / RSCFDnRMNB */
304 #define RCANFD_RMNB			(0x00a4)
305 /* RSCFDnCFDRMND / RSCFDnRMND */
306 #define RCANFD_RMND(y)			(0x00a8 + (0x04 * (y)))
307 
308 /* RSCFDnCFDRFCCx / RSCFDnRFCCx */
309 #define RCANFD_RFCC(gpriv, x)		(reg_gen4(gpriv, 0x00c0, 0x00b8) + (0x04 * (x)))
310 /* RSCFDnCFDRFSTSx / RSCFDnRFSTSx */
311 #define RCANFD_RFSTS(gpriv, x)		(RCANFD_RFCC(gpriv, x) + 0x20)
312 /* RSCFDnCFDRFPCTRx / RSCFDnRFPCTRx */
313 #define RCANFD_RFPCTR(gpriv, x)		(RCANFD_RFCC(gpriv, x) + 0x40)
314 
315 /* Common FIFO Control registers */
316 
317 /* RSCFDnCFDCFCCx / RSCFDnCFCCx */
318 #define RCANFD_CFCC(gpriv, ch, idx) \
319 	(reg_gen4(gpriv, 0x0120, 0x0118) + (0x0c * (ch)) + (0x04 * (idx)))
320 /* RSCFDnCFDCFSTSx / RSCFDnCFSTSx */
321 #define RCANFD_CFSTS(gpriv, ch, idx) \
322 	(reg_gen4(gpriv, 0x01e0, 0x0178) + (0x0c * (ch)) + (0x04 * (idx)))
323 /* RSCFDnCFDCFPCTRx / RSCFDnCFPCTRx */
324 #define RCANFD_CFPCTR(gpriv, ch, idx) \
325 	(reg_gen4(gpriv, 0x0240, 0x01d8) + (0x0c * (ch)) + (0x04 * (idx)))
326 
327 /* RSCFDnCFDFESTS / RSCFDnFESTS */
328 #define RCANFD_FESTS			(0x0238)
329 /* RSCFDnCFDFFSTS / RSCFDnFFSTS */
330 #define RCANFD_FFSTS			(0x023c)
331 /* RSCFDnCFDFMSTS / RSCFDnFMSTS */
332 #define RCANFD_FMSTS			(0x0240)
333 /* RSCFDnCFDRFISTS / RSCFDnRFISTS */
334 #define RCANFD_RFISTS			(0x0244)
335 /* RSCFDnCFDCFRISTS / RSCFDnCFRISTS */
336 #define RCANFD_CFRISTS			(0x0248)
337 /* RSCFDnCFDCFTISTS / RSCFDnCFTISTS */
338 #define RCANFD_CFTISTS			(0x024c)
339 
340 /* RSCFDnCFDTMCp / RSCFDnTMCp */
341 #define RCANFD_TMC(p)			(0x0250 + (0x01 * (p)))
342 /* RSCFDnCFDTMSTSp / RSCFDnTMSTSp */
343 #define RCANFD_TMSTS(p)			(0x02d0 + (0x01 * (p)))
344 
345 /* RSCFDnCFDTMTRSTSp / RSCFDnTMTRSTSp */
346 #define RCANFD_TMTRSTS(y)		(0x0350 + (0x04 * (y)))
347 /* RSCFDnCFDTMTARSTSp / RSCFDnTMTARSTSp */
348 #define RCANFD_TMTARSTS(y)		(0x0360 + (0x04 * (y)))
349 /* RSCFDnCFDTMTCSTSp / RSCFDnTMTCSTSp */
350 #define RCANFD_TMTCSTS(y)		(0x0370 + (0x04 * (y)))
351 /* RSCFDnCFDTMTASTSp / RSCFDnTMTASTSp */
352 #define RCANFD_TMTASTS(y)		(0x0380 + (0x04 * (y)))
353 /* RSCFDnCFDTMIECy / RSCFDnTMIECy */
354 #define RCANFD_TMIEC(y)			(0x0390 + (0x04 * (y)))
355 
356 /* RSCFDnCFDTXQCCm / RSCFDnTXQCCm */
357 #define RCANFD_TXQCC(m)			(0x03a0 + (0x04 * (m)))
358 /* RSCFDnCFDTXQSTSm / RSCFDnTXQSTSm */
359 #define RCANFD_TXQSTS(m)		(0x03c0 + (0x04 * (m)))
360 /* RSCFDnCFDTXQPCTRm / RSCFDnTXQPCTRm */
361 #define RCANFD_TXQPCTR(m)		(0x03e0 + (0x04 * (m)))
362 
363 /* RSCFDnCFDTHLCCm / RSCFDnTHLCCm */
364 #define RCANFD_THLCC(m)			(0x0400 + (0x04 * (m)))
365 /* RSCFDnCFDTHLSTSm / RSCFDnTHLSTSm */
366 #define RCANFD_THLSTS(m)		(0x0420 + (0x04 * (m)))
367 /* RSCFDnCFDTHLPCTRm / RSCFDnTHLPCTRm */
368 #define RCANFD_THLPCTR(m)		(0x0440 + (0x04 * (m)))
369 
370 /* RSCFDnCFDGTINTSTS0 / RSCFDnGTINTSTS0 */
371 #define RCANFD_GTINTSTS0		(0x0460)
372 /* RSCFDnCFDGTINTSTS1 / RSCFDnGTINTSTS1 */
373 #define RCANFD_GTINTSTS1		(0x0464)
374 /* RSCFDnCFDGTSTCFG / RSCFDnGTSTCFG */
375 #define RCANFD_GTSTCFG			(0x0468)
376 /* RSCFDnCFDGTSTCTR / RSCFDnGTSTCTR */
377 #define RCANFD_GTSTCTR			(0x046c)
378 /* RSCFDnCFDGLOCKK / RSCFDnGLOCKK */
379 #define RCANFD_GLOCKK			(0x047c)
380 /* RSCFDnCFDGRMCFG */
381 #define RCANFD_GRMCFG			(0x04fc)
382 
383 /* RSCFDnCFDGAFLIDj / RSCFDnGAFLIDj */
384 #define RCANFD_GAFLID(offset, j)	((offset) + (0x10 * (j)))
385 /* RSCFDnCFDGAFLMj / RSCFDnGAFLMj */
386 #define RCANFD_GAFLM(offset, j)		((offset) + 0x04 + (0x10 * (j)))
387 /* RSCFDnCFDGAFLP0j / RSCFDnGAFLP0j */
388 #define RCANFD_GAFLP0(offset, j)	((offset) + 0x08 + (0x10 * (j)))
389 /* RSCFDnCFDGAFLP1j / RSCFDnGAFLP1j */
390 #define RCANFD_GAFLP1(offset, j)	((offset) + 0x0c + (0x10 * (j)))
391 
392 /* Classical CAN only mode register map */
393 
394 /* RSCFDnGAFLXXXj offset */
395 #define RCANFD_C_GAFL_OFFSET		(0x0500)
396 
397 /* RSCFDnRMXXXq -> RCANFD_C_RMXXX(q) */
398 #define RCANFD_C_RMID(q)		(0x0600 + (0x10 * (q)))
399 #define RCANFD_C_RMPTR(q)		(0x0604 + (0x10 * (q)))
400 #define RCANFD_C_RMDF0(q)		(0x0608 + (0x10 * (q)))
401 #define RCANFD_C_RMDF1(q)		(0x060c + (0x10 * (q)))
402 
403 /* RSCFDnRFXXx -> RCANFD_C_RFXX(x) */
404 #define RCANFD_C_RFOFFSET	(0x0e00)
405 #define RCANFD_C_RFID(x)	(RCANFD_C_RFOFFSET + (0x10 * (x)))
406 #define RCANFD_C_RFPTR(x)	(RCANFD_C_RFOFFSET + 0x04 + (0x10 * (x)))
407 #define RCANFD_C_RFDF(x, df) \
408 		(RCANFD_C_RFOFFSET + 0x08 + (0x10 * (x)) + (0x04 * (df)))
409 
410 /* RSCFDnCFXXk -> RCANFD_C_CFXX(ch, k) */
411 #define RCANFD_C_CFOFFSET		(0x0e80)
412 
413 #define RCANFD_C_CFID(ch, idx) \
414 	(RCANFD_C_CFOFFSET + (0x30 * (ch)) + (0x10 * (idx)))
415 
416 #define RCANFD_C_CFPTR(ch, idx)	\
417 	(RCANFD_C_CFOFFSET + 0x04 + (0x30 * (ch)) + (0x10 * (idx)))
418 
419 #define RCANFD_C_CFDF(ch, idx, df) \
420 	(RCANFD_C_CFOFFSET + 0x08 + (0x30 * (ch)) + (0x10 * (idx)) + (0x04 * (df)))
421 
422 /* RSCFDnTMXXp -> RCANFD_C_TMXX(p) */
423 #define RCANFD_C_TMID(p)		(0x1000 + (0x10 * (p)))
424 #define RCANFD_C_TMPTR(p)		(0x1004 + (0x10 * (p)))
425 #define RCANFD_C_TMDF0(p)		(0x1008 + (0x10 * (p)))
426 #define RCANFD_C_TMDF1(p)		(0x100c + (0x10 * (p)))
427 
428 /* RSCFDnTHLACCm */
429 #define RCANFD_C_THLACC(m)		(0x1800 + (0x04 * (m)))
430 /* RSCFDnRPGACCr */
431 #define RCANFD_C_RPGACC(r)		(0x1900 + (0x04 * (r)))
432 
433 /* R-Car Gen4 Classical and CAN FD mode specific register map */
434 #define RCANFD_GEN4_FDCFG(m)		(0x1404 + (0x20 * (m)))
435 
436 #define RCANFD_GEN4_GAFL_OFFSET		(0x1800)
437 
438 /* CAN FD mode specific register map */
439 
440 /* RSCFDnCFDCmXXX -> RCANFD_F_XXX(m) */
441 #define RCANFD_F_DCFG(gpriv, m)		(reg_gen4(gpriv, 0x1400, 0x0500) + (0x20 * (m)))
442 #define RCANFD_F_CFDCFG(m)		(0x0504 + (0x20 * (m)))
443 #define RCANFD_F_CFDCTR(m)		(0x0508 + (0x20 * (m)))
444 #define RCANFD_F_CFDSTS(m)		(0x050c + (0x20 * (m)))
445 #define RCANFD_F_CFDCRC(m)		(0x0510 + (0x20 * (m)))
446 
447 /* RSCFDnCFDGAFLXXXj offset */
448 #define RCANFD_F_GAFL_OFFSET		(0x1000)
449 
450 /* RSCFDnCFDRMXXXq -> RCANFD_F_RMXXX(q) */
451 #define RCANFD_F_RMID(q)		(0x2000 + (0x20 * (q)))
452 #define RCANFD_F_RMPTR(q)		(0x2004 + (0x20 * (q)))
453 #define RCANFD_F_RMFDSTS(q)		(0x2008 + (0x20 * (q)))
454 #define RCANFD_F_RMDF(q, b)		(0x200c + (0x04 * (b)) + (0x20 * (q)))
455 
456 /* RSCFDnCFDRFXXx -> RCANFD_F_RFXX(x) */
457 #define RCANFD_F_RFOFFSET(gpriv)	reg_gen4(gpriv, 0x6000, 0x3000)
458 #define RCANFD_F_RFID(gpriv, x)		(RCANFD_F_RFOFFSET(gpriv) + (0x80 * (x)))
459 #define RCANFD_F_RFPTR(gpriv, x)	(RCANFD_F_RFOFFSET(gpriv) + 0x04 + (0x80 * (x)))
460 #define RCANFD_F_RFFDSTS(gpriv, x)	(RCANFD_F_RFOFFSET(gpriv) + 0x08 + (0x80 * (x)))
461 #define RCANFD_F_RFDF(gpriv, x, df) \
462 	(RCANFD_F_RFOFFSET(gpriv) + 0x0c + (0x80 * (x)) + (0x04 * (df)))
463 
464 /* RSCFDnCFDCFXXk -> RCANFD_F_CFXX(ch, k) */
465 #define RCANFD_F_CFOFFSET(gpriv)	reg_gen4(gpriv, 0x6400, 0x3400)
466 
467 #define RCANFD_F_CFID(gpriv, ch, idx) \
468 	(RCANFD_F_CFOFFSET(gpriv) + (0x180 * (ch)) + (0x80 * (idx)))
469 
470 #define RCANFD_F_CFPTR(gpriv, ch, idx) \
471 	(RCANFD_F_CFOFFSET(gpriv) + 0x04 + (0x180 * (ch)) + (0x80 * (idx)))
472 
473 #define RCANFD_F_CFFDCSTS(gpriv, ch, idx) \
474 	(RCANFD_F_CFOFFSET(gpriv) + 0x08 + (0x180 * (ch)) + (0x80 * (idx)))
475 
476 #define RCANFD_F_CFDF(gpriv, ch, idx, df) \
477 	(RCANFD_F_CFOFFSET(gpriv) + 0x0c + (0x180 * (ch)) + (0x80 * (idx)) + \
478 	 (0x04 * (df)))
479 
480 /* RSCFDnCFDTMXXp -> RCANFD_F_TMXX(p) */
481 #define RCANFD_F_TMID(p)		(0x4000 + (0x20 * (p)))
482 #define RCANFD_F_TMPTR(p)		(0x4004 + (0x20 * (p)))
483 #define RCANFD_F_TMFDCTR(p)		(0x4008 + (0x20 * (p)))
484 #define RCANFD_F_TMDF(p, b)		(0x400c + (0x20 * (p)) + (0x04 * (b)))
485 
486 /* RSCFDnCFDTHLACCm */
487 #define RCANFD_F_THLACC(m)		(0x6000 + (0x04 * (m)))
488 /* RSCFDnCFDRPGACCr */
489 #define RCANFD_F_RPGACC(r)		(0x6400 + (0x04 * (r)))
490 
491 /* Constants */
492 #define RCANFD_FIFO_DEPTH		8	/* Tx FIFO depth */
493 #define RCANFD_NAPI_WEIGHT		8	/* Rx poll quota */
494 
495 #define RCANFD_NUM_CHANNELS		8	/* Eight channels max */
496 #define RCANFD_CHANNELS_MASK		BIT((RCANFD_NUM_CHANNELS) - 1)
497 
498 #define RCANFD_GAFL_PAGENUM(entry)	((entry) / 16)
499 #define RCANFD_CHANNEL_NUMRULES		1	/* only one rule per channel */
500 
501 /* Rx FIFO is a global resource of the controller. There are 8 such FIFOs
502  * available. Each channel gets a dedicated Rx FIFO (i.e.) the channel
503  * number is added to RFFIFO index.
504  */
505 #define RCANFD_RFFIFO_IDX		0
506 
507 /* Tx/Rx or Common FIFO is a per channel resource. Each channel has 3 Common
508  * FIFOs dedicated to them. Use the first (index 0) FIFO out of the 3 for Tx.
509  */
510 #define RCANFD_CFFIFO_IDX		0
511 
512 /* fCAN clock select register settings */
513 enum rcar_canfd_fcanclk {
514 	RCANFD_CANFDCLK = 0,		/* CANFD clock */
515 	RCANFD_EXTCLK,			/* Externally input clock */
516 };
517 
518 struct rcar_canfd_global;
519 
520 struct rcar_canfd_hw_info {
521 	u8 max_channels;
522 	u8 postdiv;
523 	/* hardware features */
524 	unsigned shared_global_irqs:1;	/* Has shared global irqs */
525 	unsigned multi_channel_irqs:1;	/* Has multiple channel irqs */
526 };
527 
528 /* Channel priv data */
529 struct rcar_canfd_channel {
530 	struct can_priv can;			/* Must be the first member */
531 	struct net_device *ndev;
532 	struct rcar_canfd_global *gpriv;	/* Controller reference */
533 	void __iomem *base;			/* Register base address */
534 	struct phy *transceiver;		/* Optional transceiver */
535 	struct napi_struct napi;
536 	u32 tx_head;				/* Incremented on xmit */
537 	u32 tx_tail;				/* Incremented on xmit done */
538 	u32 channel;				/* Channel number */
539 	spinlock_t tx_lock;			/* To protect tx path */
540 };
541 
542 /* Global priv data */
543 struct rcar_canfd_global {
544 	struct rcar_canfd_channel *ch[RCANFD_NUM_CHANNELS];
545 	void __iomem *base;		/* Register base address */
546 	struct platform_device *pdev;	/* Respective platform device */
547 	struct clk *clkp;		/* Peripheral clock */
548 	struct clk *can_clk;		/* fCAN clock */
549 	enum rcar_canfd_fcanclk fcan;	/* CANFD or Ext clock */
550 	unsigned long channels_mask;	/* Enabled channels mask */
551 	bool fdmode;			/* CAN FD or Classical CAN only mode */
552 	struct reset_control *rstc1;
553 	struct reset_control *rstc2;
554 	const struct rcar_canfd_hw_info *info;
555 };
556 
557 /* CAN FD mode nominal rate constants */
558 static const struct can_bittiming_const rcar_canfd_nom_bittiming_const = {
559 	.name = RCANFD_DRV_NAME,
560 	.tseg1_min = 2,
561 	.tseg1_max = 128,
562 	.tseg2_min = 2,
563 	.tseg2_max = 32,
564 	.sjw_max = 32,
565 	.brp_min = 1,
566 	.brp_max = 1024,
567 	.brp_inc = 1,
568 };
569 
570 /* CAN FD mode data rate constants */
571 static const struct can_bittiming_const rcar_canfd_data_bittiming_const = {
572 	.name = RCANFD_DRV_NAME,
573 	.tseg1_min = 2,
574 	.tseg1_max = 16,
575 	.tseg2_min = 2,
576 	.tseg2_max = 8,
577 	.sjw_max = 8,
578 	.brp_min = 1,
579 	.brp_max = 256,
580 	.brp_inc = 1,
581 };
582 
583 /* Classical CAN mode bitrate constants */
584 static const struct can_bittiming_const rcar_canfd_bittiming_const = {
585 	.name = RCANFD_DRV_NAME,
586 	.tseg1_min = 4,
587 	.tseg1_max = 16,
588 	.tseg2_min = 2,
589 	.tseg2_max = 8,
590 	.sjw_max = 4,
591 	.brp_min = 1,
592 	.brp_max = 1024,
593 	.brp_inc = 1,
594 };
595 
596 static const struct rcar_canfd_hw_info rcar_gen3_hw_info = {
597 	.max_channels = 2,
598 	.postdiv = 2,
599 	.shared_global_irqs = 1,
600 };
601 
602 static const struct rcar_canfd_hw_info rcar_gen4_hw_info = {
603 	.max_channels = 8,
604 	.postdiv = 2,
605 	.shared_global_irqs = 1,
606 };
607 
608 static const struct rcar_canfd_hw_info rzg2l_hw_info = {
609 	.max_channels = 2,
610 	.postdiv = 1,
611 	.multi_channel_irqs = 1,
612 };
613 
614 /* Helper functions */
615 static inline bool is_gen4(struct rcar_canfd_global *gpriv)
616 {
617 	return gpriv->info == &rcar_gen4_hw_info;
618 }
619 
620 static inline u32 reg_gen4(struct rcar_canfd_global *gpriv,
621 			   u32 gen4, u32 not_gen4)
622 {
623 	return is_gen4(gpriv) ? gen4 : not_gen4;
624 }
625 
626 static inline void rcar_canfd_update(u32 mask, u32 val, u32 __iomem *reg)
627 {
628 	u32 data = readl(reg);
629 
630 	data &= ~mask;
631 	data |= (val & mask);
632 	writel(data, reg);
633 }
634 
635 static inline u32 rcar_canfd_read(void __iomem *base, u32 offset)
636 {
637 	return readl(base + (offset));
638 }
639 
640 static inline void rcar_canfd_write(void __iomem *base, u32 offset, u32 val)
641 {
642 	writel(val, base + (offset));
643 }
644 
645 static void rcar_canfd_set_bit(void __iomem *base, u32 reg, u32 val)
646 {
647 	rcar_canfd_update(val, val, base + (reg));
648 }
649 
650 static void rcar_canfd_clear_bit(void __iomem *base, u32 reg, u32 val)
651 {
652 	rcar_canfd_update(val, 0, base + (reg));
653 }
654 
655 static void rcar_canfd_update_bit(void __iomem *base, u32 reg,
656 				  u32 mask, u32 val)
657 {
658 	rcar_canfd_update(mask, val, base + (reg));
659 }
660 
661 static void rcar_canfd_get_data(struct rcar_canfd_channel *priv,
662 				struct canfd_frame *cf, u32 off)
663 {
664 	u32 i, lwords;
665 
666 	lwords = DIV_ROUND_UP(cf->len, sizeof(u32));
667 	for (i = 0; i < lwords; i++)
668 		*((u32 *)cf->data + i) =
669 			rcar_canfd_read(priv->base, off + (i * sizeof(u32)));
670 }
671 
672 static void rcar_canfd_put_data(struct rcar_canfd_channel *priv,
673 				struct canfd_frame *cf, u32 off)
674 {
675 	u32 i, lwords;
676 
677 	lwords = DIV_ROUND_UP(cf->len, sizeof(u32));
678 	for (i = 0; i < lwords; i++)
679 		rcar_canfd_write(priv->base, off + (i * sizeof(u32)),
680 				 *((u32 *)cf->data + i));
681 }
682 
683 static void rcar_canfd_tx_failure_cleanup(struct net_device *ndev)
684 {
685 	u32 i;
686 
687 	for (i = 0; i < RCANFD_FIFO_DEPTH; i++)
688 		can_free_echo_skb(ndev, i, NULL);
689 }
690 
691 static void rcar_canfd_set_mode(struct rcar_canfd_global *gpriv)
692 {
693 	if (is_gen4(gpriv)) {
694 		u32 ch, val = gpriv->fdmode ? RCANFD_GEN4_FDCFG_FDOE
695 					    : RCANFD_GEN4_FDCFG_CLOE;
696 
697 		for_each_set_bit(ch, &gpriv->channels_mask,
698 				 gpriv->info->max_channels)
699 			rcar_canfd_set_bit(gpriv->base, RCANFD_GEN4_FDCFG(ch),
700 					   val);
701 	} else {
702 		if (gpriv->fdmode)
703 			rcar_canfd_set_bit(gpriv->base, RCANFD_GRMCFG,
704 					   RCANFD_GRMCFG_RCMC);
705 		else
706 			rcar_canfd_clear_bit(gpriv->base, RCANFD_GRMCFG,
707 					     RCANFD_GRMCFG_RCMC);
708 	}
709 }
710 
711 static int rcar_canfd_reset_controller(struct rcar_canfd_global *gpriv)
712 {
713 	u32 sts, ch;
714 	int err;
715 
716 	/* Check RAMINIT flag as CAN RAM initialization takes place
717 	 * after the MCU reset
718 	 */
719 	err = readl_poll_timeout((gpriv->base + RCANFD_GSTS), sts,
720 				 !(sts & RCANFD_GSTS_GRAMINIT), 2, 500000);
721 	if (err) {
722 		dev_dbg(&gpriv->pdev->dev, "global raminit failed\n");
723 		return err;
724 	}
725 
726 	/* Transition to Global Reset mode */
727 	rcar_canfd_clear_bit(gpriv->base, RCANFD_GCTR, RCANFD_GCTR_GSLPR);
728 	rcar_canfd_update_bit(gpriv->base, RCANFD_GCTR,
729 			      RCANFD_GCTR_GMDC_MASK, RCANFD_GCTR_GMDC_GRESET);
730 
731 	/* Ensure Global reset mode */
732 	err = readl_poll_timeout((gpriv->base + RCANFD_GSTS), sts,
733 				 (sts & RCANFD_GSTS_GRSTSTS), 2, 500000);
734 	if (err) {
735 		dev_dbg(&gpriv->pdev->dev, "global reset failed\n");
736 		return err;
737 	}
738 
739 	/* Reset Global error flags */
740 	rcar_canfd_write(gpriv->base, RCANFD_GERFL, 0x0);
741 
742 	/* Set the controller into appropriate mode */
743 	rcar_canfd_set_mode(gpriv);
744 
745 	/* Transition all Channels to reset mode */
746 	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
747 		rcar_canfd_clear_bit(gpriv->base,
748 				     RCANFD_CCTR(ch), RCANFD_CCTR_CSLPR);
749 
750 		rcar_canfd_update_bit(gpriv->base, RCANFD_CCTR(ch),
751 				      RCANFD_CCTR_CHMDC_MASK,
752 				      RCANFD_CCTR_CHDMC_CRESET);
753 
754 		/* Ensure Channel reset mode */
755 		err = readl_poll_timeout((gpriv->base + RCANFD_CSTS(ch)), sts,
756 					 (sts & RCANFD_CSTS_CRSTSTS),
757 					 2, 500000);
758 		if (err) {
759 			dev_dbg(&gpriv->pdev->dev,
760 				"channel %u reset failed\n", ch);
761 			return err;
762 		}
763 	}
764 	return 0;
765 }
766 
767 static void rcar_canfd_configure_controller(struct rcar_canfd_global *gpriv)
768 {
769 	u32 cfg, ch;
770 
771 	/* Global configuration settings */
772 
773 	/* ECC Error flag Enable */
774 	cfg = RCANFD_GCFG_EEFE;
775 
776 	if (gpriv->fdmode)
777 		/* Truncate payload to configured message size RFPLS */
778 		cfg |= RCANFD_GCFG_CMPOC;
779 
780 	/* Set External Clock if selected */
781 	if (gpriv->fcan != RCANFD_CANFDCLK)
782 		cfg |= RCANFD_GCFG_DCS;
783 
784 	rcar_canfd_set_bit(gpriv->base, RCANFD_GCFG, cfg);
785 
786 	/* Channel configuration settings */
787 	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
788 		rcar_canfd_set_bit(gpriv->base, RCANFD_CCTR(ch),
789 				   RCANFD_CCTR_ERRD);
790 		rcar_canfd_update_bit(gpriv->base, RCANFD_CCTR(ch),
791 				      RCANFD_CCTR_BOM_MASK,
792 				      RCANFD_CCTR_BOM_BENTRY);
793 	}
794 }
795 
796 static void rcar_canfd_configure_afl_rules(struct rcar_canfd_global *gpriv,
797 					   u32 ch)
798 {
799 	u32 cfg;
800 	int offset, start, page, num_rules = RCANFD_CHANNEL_NUMRULES;
801 	u32 ridx = ch + RCANFD_RFFIFO_IDX;
802 
803 	if (ch == 0) {
804 		start = 0; /* Channel 0 always starts from 0th rule */
805 	} else {
806 		/* Get number of Channel 0 rules and adjust */
807 		cfg = rcar_canfd_read(gpriv->base, RCANFD_GAFLCFG(ch));
808 		start = RCANFD_GAFLCFG_GETRNC(gpriv, 0, cfg);
809 	}
810 
811 	/* Enable write access to entry */
812 	page = RCANFD_GAFL_PAGENUM(start);
813 	rcar_canfd_set_bit(gpriv->base, RCANFD_GAFLECTR,
814 			   (RCANFD_GAFLECTR_AFLPN(gpriv, page) |
815 			    RCANFD_GAFLECTR_AFLDAE));
816 
817 	/* Write number of rules for channel */
818 	rcar_canfd_set_bit(gpriv->base, RCANFD_GAFLCFG(ch),
819 			   RCANFD_GAFLCFG_SETRNC(gpriv, ch, num_rules));
820 	if (is_gen4(gpriv))
821 		offset = RCANFD_GEN4_GAFL_OFFSET;
822 	else if (gpriv->fdmode)
823 		offset = RCANFD_F_GAFL_OFFSET;
824 	else
825 		offset = RCANFD_C_GAFL_OFFSET;
826 
827 	/* Accept all IDs */
828 	rcar_canfd_write(gpriv->base, RCANFD_GAFLID(offset, start), 0);
829 	/* IDE or RTR is not considered for matching */
830 	rcar_canfd_write(gpriv->base, RCANFD_GAFLM(offset, start), 0);
831 	/* Any data length accepted */
832 	rcar_canfd_write(gpriv->base, RCANFD_GAFLP0(offset, start), 0);
833 	/* Place the msg in corresponding Rx FIFO entry */
834 	rcar_canfd_set_bit(gpriv->base, RCANFD_GAFLP1(offset, start),
835 			   RCANFD_GAFLP1_GAFLFDP(ridx));
836 
837 	/* Disable write access to page */
838 	rcar_canfd_clear_bit(gpriv->base,
839 			     RCANFD_GAFLECTR, RCANFD_GAFLECTR_AFLDAE);
840 }
841 
842 static void rcar_canfd_configure_rx(struct rcar_canfd_global *gpriv, u32 ch)
843 {
844 	/* Rx FIFO is used for reception */
845 	u32 cfg;
846 	u16 rfdc, rfpls;
847 
848 	/* Select Rx FIFO based on channel */
849 	u32 ridx = ch + RCANFD_RFFIFO_IDX;
850 
851 	rfdc = 2;		/* b010 - 8 messages Rx FIFO depth */
852 	if (gpriv->fdmode)
853 		rfpls = 7;	/* b111 - Max 64 bytes payload */
854 	else
855 		rfpls = 0;	/* b000 - Max 8 bytes payload */
856 
857 	cfg = (RCANFD_RFCC_RFIM | RCANFD_RFCC_RFDC(rfdc) |
858 		RCANFD_RFCC_RFPLS(rfpls) | RCANFD_RFCC_RFIE);
859 	rcar_canfd_write(gpriv->base, RCANFD_RFCC(gpriv, ridx), cfg);
860 }
861 
862 static void rcar_canfd_configure_tx(struct rcar_canfd_global *gpriv, u32 ch)
863 {
864 	/* Tx/Rx(Common) FIFO configured in Tx mode is
865 	 * used for transmission
866 	 *
867 	 * Each channel has 3 Common FIFO dedicated to them.
868 	 * Use the 1st (index 0) out of 3
869 	 */
870 	u32 cfg;
871 	u16 cftml, cfm, cfdc, cfpls;
872 
873 	cftml = 0;		/* 0th buffer */
874 	cfm = 1;		/* b01 - Transmit mode */
875 	cfdc = 2;		/* b010 - 8 messages Tx FIFO depth */
876 	if (gpriv->fdmode)
877 		cfpls = 7;	/* b111 - Max 64 bytes payload */
878 	else
879 		cfpls = 0;	/* b000 - Max 8 bytes payload */
880 
881 	cfg = (RCANFD_CFCC_CFTML(gpriv, cftml) | RCANFD_CFCC_CFM(gpriv, cfm) |
882 		RCANFD_CFCC_CFIM | RCANFD_CFCC_CFDC(gpriv, cfdc) |
883 		RCANFD_CFCC_CFPLS(cfpls) | RCANFD_CFCC_CFTXIE);
884 	rcar_canfd_write(gpriv->base, RCANFD_CFCC(gpriv, ch, RCANFD_CFFIFO_IDX), cfg);
885 
886 	if (gpriv->fdmode)
887 		/* Clear FD mode specific control/status register */
888 		rcar_canfd_write(gpriv->base,
889 				 RCANFD_F_CFFDCSTS(gpriv, ch, RCANFD_CFFIFO_IDX), 0);
890 }
891 
892 static void rcar_canfd_enable_global_interrupts(struct rcar_canfd_global *gpriv)
893 {
894 	u32 ctr;
895 
896 	/* Clear any stray error interrupt flags */
897 	rcar_canfd_write(gpriv->base, RCANFD_GERFL, 0);
898 
899 	/* Global interrupts setup */
900 	ctr = RCANFD_GCTR_MEIE;
901 	if (gpriv->fdmode)
902 		ctr |= RCANFD_GCTR_CFMPOFIE;
903 
904 	rcar_canfd_set_bit(gpriv->base, RCANFD_GCTR, ctr);
905 }
906 
907 static void rcar_canfd_disable_global_interrupts(struct rcar_canfd_global
908 						 *gpriv)
909 {
910 	/* Disable all interrupts */
911 	rcar_canfd_write(gpriv->base, RCANFD_GCTR, 0);
912 
913 	/* Clear any stray error interrupt flags */
914 	rcar_canfd_write(gpriv->base, RCANFD_GERFL, 0);
915 }
916 
917 static void rcar_canfd_enable_channel_interrupts(struct rcar_canfd_channel
918 						 *priv)
919 {
920 	u32 ctr, ch = priv->channel;
921 
922 	/* Clear any stray error flags */
923 	rcar_canfd_write(priv->base, RCANFD_CERFL(ch), 0);
924 
925 	/* Channel interrupts setup */
926 	ctr = (RCANFD_CCTR_TAIE |
927 	       RCANFD_CCTR_ALIE | RCANFD_CCTR_BLIE |
928 	       RCANFD_CCTR_OLIE | RCANFD_CCTR_BORIE |
929 	       RCANFD_CCTR_BOEIE | RCANFD_CCTR_EPIE |
930 	       RCANFD_CCTR_EWIE | RCANFD_CCTR_BEIE);
931 	rcar_canfd_set_bit(priv->base, RCANFD_CCTR(ch), ctr);
932 }
933 
934 static void rcar_canfd_disable_channel_interrupts(struct rcar_canfd_channel
935 						  *priv)
936 {
937 	u32 ctr, ch = priv->channel;
938 
939 	ctr = (RCANFD_CCTR_TAIE |
940 	       RCANFD_CCTR_ALIE | RCANFD_CCTR_BLIE |
941 	       RCANFD_CCTR_OLIE | RCANFD_CCTR_BORIE |
942 	       RCANFD_CCTR_BOEIE | RCANFD_CCTR_EPIE |
943 	       RCANFD_CCTR_EWIE | RCANFD_CCTR_BEIE);
944 	rcar_canfd_clear_bit(priv->base, RCANFD_CCTR(ch), ctr);
945 
946 	/* Clear any stray error flags */
947 	rcar_canfd_write(priv->base, RCANFD_CERFL(ch), 0);
948 }
949 
950 static void rcar_canfd_global_error(struct net_device *ndev)
951 {
952 	struct rcar_canfd_channel *priv = netdev_priv(ndev);
953 	struct rcar_canfd_global *gpriv = priv->gpriv;
954 	struct net_device_stats *stats = &ndev->stats;
955 	u32 ch = priv->channel;
956 	u32 gerfl, sts;
957 	u32 ridx = ch + RCANFD_RFFIFO_IDX;
958 
959 	gerfl = rcar_canfd_read(priv->base, RCANFD_GERFL);
960 	if (gerfl & RCANFD_GERFL_EEF(ch)) {
961 		netdev_dbg(ndev, "Ch%u: ECC Error flag\n", ch);
962 		stats->tx_dropped++;
963 	}
964 	if (gerfl & RCANFD_GERFL_MES) {
965 		sts = rcar_canfd_read(priv->base,
966 				      RCANFD_CFSTS(gpriv, ch, RCANFD_CFFIFO_IDX));
967 		if (sts & RCANFD_CFSTS_CFMLT) {
968 			netdev_dbg(ndev, "Tx Message Lost flag\n");
969 			stats->tx_dropped++;
970 			rcar_canfd_write(priv->base,
971 					 RCANFD_CFSTS(gpriv, ch, RCANFD_CFFIFO_IDX),
972 					 sts & ~RCANFD_CFSTS_CFMLT);
973 		}
974 
975 		sts = rcar_canfd_read(priv->base, RCANFD_RFSTS(gpriv, ridx));
976 		if (sts & RCANFD_RFSTS_RFMLT) {
977 			netdev_dbg(ndev, "Rx Message Lost flag\n");
978 			stats->rx_dropped++;
979 			rcar_canfd_write(priv->base, RCANFD_RFSTS(gpriv, ridx),
980 					 sts & ~RCANFD_RFSTS_RFMLT);
981 		}
982 	}
983 	if (gpriv->fdmode && gerfl & RCANFD_GERFL_CMPOF) {
984 		/* Message Lost flag will be set for respective channel
985 		 * when this condition happens with counters and flags
986 		 * already updated.
987 		 */
988 		netdev_dbg(ndev, "global payload overflow interrupt\n");
989 	}
990 
991 	/* Clear all global error interrupts. Only affected channels bits
992 	 * get cleared
993 	 */
994 	rcar_canfd_write(priv->base, RCANFD_GERFL, 0);
995 }
996 
997 static void rcar_canfd_error(struct net_device *ndev, u32 cerfl,
998 			     u16 txerr, u16 rxerr)
999 {
1000 	struct rcar_canfd_channel *priv = netdev_priv(ndev);
1001 	struct net_device_stats *stats = &ndev->stats;
1002 	struct can_frame *cf;
1003 	struct sk_buff *skb;
1004 	u32 ch = priv->channel;
1005 
1006 	netdev_dbg(ndev, "ch erfl %x txerr %u rxerr %u\n", cerfl, txerr, rxerr);
1007 
1008 	/* Propagate the error condition to the CAN stack */
1009 	skb = alloc_can_err_skb(ndev, &cf);
1010 	if (!skb) {
1011 		stats->rx_dropped++;
1012 		return;
1013 	}
1014 
1015 	/* Channel error interrupts */
1016 	if (cerfl & RCANFD_CERFL_BEF) {
1017 		netdev_dbg(ndev, "Bus error\n");
1018 		cf->can_id |= CAN_ERR_BUSERROR | CAN_ERR_PROT;
1019 		cf->data[2] = CAN_ERR_PROT_UNSPEC;
1020 		priv->can.can_stats.bus_error++;
1021 	}
1022 	if (cerfl & RCANFD_CERFL_ADERR) {
1023 		netdev_dbg(ndev, "ACK Delimiter Error\n");
1024 		stats->tx_errors++;
1025 		cf->data[3] |= CAN_ERR_PROT_LOC_ACK_DEL;
1026 	}
1027 	if (cerfl & RCANFD_CERFL_B0ERR) {
1028 		netdev_dbg(ndev, "Bit Error (dominant)\n");
1029 		stats->tx_errors++;
1030 		cf->data[2] |= CAN_ERR_PROT_BIT0;
1031 	}
1032 	if (cerfl & RCANFD_CERFL_B1ERR) {
1033 		netdev_dbg(ndev, "Bit Error (recessive)\n");
1034 		stats->tx_errors++;
1035 		cf->data[2] |= CAN_ERR_PROT_BIT1;
1036 	}
1037 	if (cerfl & RCANFD_CERFL_CERR) {
1038 		netdev_dbg(ndev, "CRC Error\n");
1039 		stats->rx_errors++;
1040 		cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ;
1041 	}
1042 	if (cerfl & RCANFD_CERFL_AERR) {
1043 		netdev_dbg(ndev, "ACK Error\n");
1044 		stats->tx_errors++;
1045 		cf->can_id |= CAN_ERR_ACK;
1046 		cf->data[3] |= CAN_ERR_PROT_LOC_ACK;
1047 	}
1048 	if (cerfl & RCANFD_CERFL_FERR) {
1049 		netdev_dbg(ndev, "Form Error\n");
1050 		stats->rx_errors++;
1051 		cf->data[2] |= CAN_ERR_PROT_FORM;
1052 	}
1053 	if (cerfl & RCANFD_CERFL_SERR) {
1054 		netdev_dbg(ndev, "Stuff Error\n");
1055 		stats->rx_errors++;
1056 		cf->data[2] |= CAN_ERR_PROT_STUFF;
1057 	}
1058 	if (cerfl & RCANFD_CERFL_ALF) {
1059 		netdev_dbg(ndev, "Arbitration lost Error\n");
1060 		priv->can.can_stats.arbitration_lost++;
1061 		cf->can_id |= CAN_ERR_LOSTARB;
1062 		cf->data[0] |= CAN_ERR_LOSTARB_UNSPEC;
1063 	}
1064 	if (cerfl & RCANFD_CERFL_BLF) {
1065 		netdev_dbg(ndev, "Bus Lock Error\n");
1066 		stats->rx_errors++;
1067 		cf->can_id |= CAN_ERR_BUSERROR;
1068 	}
1069 	if (cerfl & RCANFD_CERFL_EWF) {
1070 		netdev_dbg(ndev, "Error warning interrupt\n");
1071 		priv->can.state = CAN_STATE_ERROR_WARNING;
1072 		priv->can.can_stats.error_warning++;
1073 		cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
1074 		cf->data[1] = txerr > rxerr ? CAN_ERR_CRTL_TX_WARNING :
1075 			CAN_ERR_CRTL_RX_WARNING;
1076 		cf->data[6] = txerr;
1077 		cf->data[7] = rxerr;
1078 	}
1079 	if (cerfl & RCANFD_CERFL_EPF) {
1080 		netdev_dbg(ndev, "Error passive interrupt\n");
1081 		priv->can.state = CAN_STATE_ERROR_PASSIVE;
1082 		priv->can.can_stats.error_passive++;
1083 		cf->can_id |= CAN_ERR_CRTL | CAN_ERR_CNT;
1084 		cf->data[1] = txerr > rxerr ? CAN_ERR_CRTL_TX_PASSIVE :
1085 			CAN_ERR_CRTL_RX_PASSIVE;
1086 		cf->data[6] = txerr;
1087 		cf->data[7] = rxerr;
1088 	}
1089 	if (cerfl & RCANFD_CERFL_BOEF) {
1090 		netdev_dbg(ndev, "Bus-off entry interrupt\n");
1091 		rcar_canfd_tx_failure_cleanup(ndev);
1092 		priv->can.state = CAN_STATE_BUS_OFF;
1093 		priv->can.can_stats.bus_off++;
1094 		can_bus_off(ndev);
1095 		cf->can_id |= CAN_ERR_BUSOFF;
1096 	}
1097 	if (cerfl & RCANFD_CERFL_OVLF) {
1098 		netdev_dbg(ndev,
1099 			   "Overload Frame Transmission error interrupt\n");
1100 		stats->tx_errors++;
1101 		cf->can_id |= CAN_ERR_PROT;
1102 		cf->data[2] |= CAN_ERR_PROT_OVERLOAD;
1103 	}
1104 
1105 	/* Clear channel error interrupts that are handled */
1106 	rcar_canfd_write(priv->base, RCANFD_CERFL(ch),
1107 			 RCANFD_CERFL_ERR(~cerfl));
1108 	netif_rx(skb);
1109 }
1110 
1111 static void rcar_canfd_tx_done(struct net_device *ndev)
1112 {
1113 	struct rcar_canfd_channel *priv = netdev_priv(ndev);
1114 	struct rcar_canfd_global *gpriv = priv->gpriv;
1115 	struct net_device_stats *stats = &ndev->stats;
1116 	u32 sts;
1117 	unsigned long flags;
1118 	u32 ch = priv->channel;
1119 
1120 	do {
1121 		u8 unsent, sent;
1122 
1123 		sent = priv->tx_tail % RCANFD_FIFO_DEPTH;
1124 		stats->tx_packets++;
1125 		stats->tx_bytes += can_get_echo_skb(ndev, sent, NULL);
1126 
1127 		spin_lock_irqsave(&priv->tx_lock, flags);
1128 		priv->tx_tail++;
1129 		sts = rcar_canfd_read(priv->base,
1130 				      RCANFD_CFSTS(gpriv, ch, RCANFD_CFFIFO_IDX));
1131 		unsent = RCANFD_CFSTS_CFMC(sts);
1132 
1133 		/* Wake producer only when there is room */
1134 		if (unsent != RCANFD_FIFO_DEPTH)
1135 			netif_wake_queue(ndev);
1136 
1137 		if (priv->tx_head - priv->tx_tail <= unsent) {
1138 			spin_unlock_irqrestore(&priv->tx_lock, flags);
1139 			break;
1140 		}
1141 		spin_unlock_irqrestore(&priv->tx_lock, flags);
1142 
1143 	} while (1);
1144 
1145 	/* Clear interrupt */
1146 	rcar_canfd_write(priv->base, RCANFD_CFSTS(gpriv, ch, RCANFD_CFFIFO_IDX),
1147 			 sts & ~RCANFD_CFSTS_CFTXIF);
1148 }
1149 
1150 static void rcar_canfd_handle_global_err(struct rcar_canfd_global *gpriv, u32 ch)
1151 {
1152 	struct rcar_canfd_channel *priv = gpriv->ch[ch];
1153 	struct net_device *ndev = priv->ndev;
1154 	u32 gerfl;
1155 
1156 	/* Handle global error interrupts */
1157 	gerfl = rcar_canfd_read(priv->base, RCANFD_GERFL);
1158 	if (unlikely(RCANFD_GERFL_ERR(gpriv, gerfl)))
1159 		rcar_canfd_global_error(ndev);
1160 }
1161 
1162 static irqreturn_t rcar_canfd_global_err_interrupt(int irq, void *dev_id)
1163 {
1164 	struct rcar_canfd_global *gpriv = dev_id;
1165 	u32 ch;
1166 
1167 	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels)
1168 		rcar_canfd_handle_global_err(gpriv, ch);
1169 
1170 	return IRQ_HANDLED;
1171 }
1172 
1173 static void rcar_canfd_handle_global_receive(struct rcar_canfd_global *gpriv, u32 ch)
1174 {
1175 	struct rcar_canfd_channel *priv = gpriv->ch[ch];
1176 	u32 ridx = ch + RCANFD_RFFIFO_IDX;
1177 	u32 sts, cc;
1178 
1179 	/* Handle Rx interrupts */
1180 	sts = rcar_canfd_read(priv->base, RCANFD_RFSTS(gpriv, ridx));
1181 	cc = rcar_canfd_read(priv->base, RCANFD_RFCC(gpriv, ridx));
1182 	if (likely(sts & RCANFD_RFSTS_RFIF &&
1183 		   cc & RCANFD_RFCC_RFIE)) {
1184 		if (napi_schedule_prep(&priv->napi)) {
1185 			/* Disable Rx FIFO interrupts */
1186 			rcar_canfd_clear_bit(priv->base,
1187 					     RCANFD_RFCC(gpriv, ridx),
1188 					     RCANFD_RFCC_RFIE);
1189 			__napi_schedule(&priv->napi);
1190 		}
1191 	}
1192 }
1193 
1194 static irqreturn_t rcar_canfd_global_receive_fifo_interrupt(int irq, void *dev_id)
1195 {
1196 	struct rcar_canfd_global *gpriv = dev_id;
1197 	u32 ch;
1198 
1199 	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels)
1200 		rcar_canfd_handle_global_receive(gpriv, ch);
1201 
1202 	return IRQ_HANDLED;
1203 }
1204 
1205 static irqreturn_t rcar_canfd_global_interrupt(int irq, void *dev_id)
1206 {
1207 	struct rcar_canfd_global *gpriv = dev_id;
1208 	u32 ch;
1209 
1210 	/* Global error interrupts still indicate a condition specific
1211 	 * to a channel. RxFIFO interrupt is a global interrupt.
1212 	 */
1213 	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
1214 		rcar_canfd_handle_global_err(gpriv, ch);
1215 		rcar_canfd_handle_global_receive(gpriv, ch);
1216 	}
1217 	return IRQ_HANDLED;
1218 }
1219 
1220 static void rcar_canfd_state_change(struct net_device *ndev,
1221 				    u16 txerr, u16 rxerr)
1222 {
1223 	struct rcar_canfd_channel *priv = netdev_priv(ndev);
1224 	struct net_device_stats *stats = &ndev->stats;
1225 	enum can_state rx_state, tx_state, state = priv->can.state;
1226 	struct can_frame *cf;
1227 	struct sk_buff *skb;
1228 
1229 	/* Handle transition from error to normal states */
1230 	if (txerr < 96 && rxerr < 96)
1231 		state = CAN_STATE_ERROR_ACTIVE;
1232 	else if (txerr < 128 && rxerr < 128)
1233 		state = CAN_STATE_ERROR_WARNING;
1234 
1235 	if (state != priv->can.state) {
1236 		netdev_dbg(ndev, "state: new %d, old %d: txerr %u, rxerr %u\n",
1237 			   state, priv->can.state, txerr, rxerr);
1238 		skb = alloc_can_err_skb(ndev, &cf);
1239 		if (!skb) {
1240 			stats->rx_dropped++;
1241 			return;
1242 		}
1243 		tx_state = txerr >= rxerr ? state : 0;
1244 		rx_state = txerr <= rxerr ? state : 0;
1245 
1246 		can_change_state(ndev, cf, tx_state, rx_state);
1247 		netif_rx(skb);
1248 	}
1249 }
1250 
1251 static void rcar_canfd_handle_channel_tx(struct rcar_canfd_global *gpriv, u32 ch)
1252 {
1253 	struct rcar_canfd_channel *priv = gpriv->ch[ch];
1254 	struct net_device *ndev = priv->ndev;
1255 	u32 sts;
1256 
1257 	/* Handle Tx interrupts */
1258 	sts = rcar_canfd_read(priv->base,
1259 			      RCANFD_CFSTS(gpriv, ch, RCANFD_CFFIFO_IDX));
1260 	if (likely(sts & RCANFD_CFSTS_CFTXIF))
1261 		rcar_canfd_tx_done(ndev);
1262 }
1263 
1264 static irqreturn_t rcar_canfd_channel_tx_interrupt(int irq, void *dev_id)
1265 {
1266 	struct rcar_canfd_channel *priv = dev_id;
1267 
1268 	rcar_canfd_handle_channel_tx(priv->gpriv, priv->channel);
1269 
1270 	return IRQ_HANDLED;
1271 }
1272 
1273 static void rcar_canfd_handle_channel_err(struct rcar_canfd_global *gpriv, u32 ch)
1274 {
1275 	struct rcar_canfd_channel *priv = gpriv->ch[ch];
1276 	struct net_device *ndev = priv->ndev;
1277 	u16 txerr, rxerr;
1278 	u32 sts, cerfl;
1279 
1280 	/* Handle channel error interrupts */
1281 	cerfl = rcar_canfd_read(priv->base, RCANFD_CERFL(ch));
1282 	sts = rcar_canfd_read(priv->base, RCANFD_CSTS(ch));
1283 	txerr = RCANFD_CSTS_TECCNT(sts);
1284 	rxerr = RCANFD_CSTS_RECCNT(sts);
1285 	if (unlikely(RCANFD_CERFL_ERR(cerfl)))
1286 		rcar_canfd_error(ndev, cerfl, txerr, rxerr);
1287 
1288 	/* Handle state change to lower states */
1289 	if (unlikely(priv->can.state != CAN_STATE_ERROR_ACTIVE &&
1290 		     priv->can.state != CAN_STATE_BUS_OFF))
1291 		rcar_canfd_state_change(ndev, txerr, rxerr);
1292 }
1293 
1294 static irqreturn_t rcar_canfd_channel_err_interrupt(int irq, void *dev_id)
1295 {
1296 	struct rcar_canfd_channel *priv = dev_id;
1297 
1298 	rcar_canfd_handle_channel_err(priv->gpriv, priv->channel);
1299 
1300 	return IRQ_HANDLED;
1301 }
1302 
1303 static irqreturn_t rcar_canfd_channel_interrupt(int irq, void *dev_id)
1304 {
1305 	struct rcar_canfd_global *gpriv = dev_id;
1306 	u32 ch;
1307 
1308 	/* Common FIFO is a per channel resource */
1309 	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
1310 		rcar_canfd_handle_channel_err(gpriv, ch);
1311 		rcar_canfd_handle_channel_tx(gpriv, ch);
1312 	}
1313 
1314 	return IRQ_HANDLED;
1315 }
1316 
1317 static void rcar_canfd_set_bittiming(struct net_device *dev)
1318 {
1319 	struct rcar_canfd_channel *priv = netdev_priv(dev);
1320 	struct rcar_canfd_global *gpriv = priv->gpriv;
1321 	const struct can_bittiming *bt = &priv->can.bittiming;
1322 	const struct can_bittiming *dbt = &priv->can.data_bittiming;
1323 	u16 brp, sjw, tseg1, tseg2;
1324 	u32 cfg;
1325 	u32 ch = priv->channel;
1326 
1327 	/* Nominal bit timing settings */
1328 	brp = bt->brp - 1;
1329 	sjw = bt->sjw - 1;
1330 	tseg1 = bt->prop_seg + bt->phase_seg1 - 1;
1331 	tseg2 = bt->phase_seg2 - 1;
1332 
1333 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
1334 		/* CAN FD only mode */
1335 		cfg = (RCANFD_NCFG_NTSEG1(gpriv, tseg1) | RCANFD_NCFG_NBRP(brp) |
1336 		       RCANFD_NCFG_NSJW(gpriv, sjw) | RCANFD_NCFG_NTSEG2(gpriv, tseg2));
1337 
1338 		rcar_canfd_write(priv->base, RCANFD_CCFG(ch), cfg);
1339 		netdev_dbg(priv->ndev, "nrate: brp %u, sjw %u, tseg1 %u, tseg2 %u\n",
1340 			   brp, sjw, tseg1, tseg2);
1341 
1342 		/* Data bit timing settings */
1343 		brp = dbt->brp - 1;
1344 		sjw = dbt->sjw - 1;
1345 		tseg1 = dbt->prop_seg + dbt->phase_seg1 - 1;
1346 		tseg2 = dbt->phase_seg2 - 1;
1347 
1348 		cfg = (RCANFD_DCFG_DTSEG1(gpriv, tseg1) | RCANFD_DCFG_DBRP(brp) |
1349 		       RCANFD_DCFG_DSJW(gpriv, sjw) | RCANFD_DCFG_DTSEG2(gpriv, tseg2));
1350 
1351 		rcar_canfd_write(priv->base, RCANFD_F_DCFG(gpriv, ch), cfg);
1352 		netdev_dbg(priv->ndev, "drate: brp %u, sjw %u, tseg1 %u, tseg2 %u\n",
1353 			   brp, sjw, tseg1, tseg2);
1354 	} else {
1355 		/* Classical CAN only mode */
1356 		if (is_gen4(gpriv)) {
1357 			cfg = (RCANFD_NCFG_NTSEG1(gpriv, tseg1) |
1358 			       RCANFD_NCFG_NBRP(brp) |
1359 			       RCANFD_NCFG_NSJW(gpriv, sjw) |
1360 			       RCANFD_NCFG_NTSEG2(gpriv, tseg2));
1361 		} else {
1362 			cfg = (RCANFD_CFG_TSEG1(tseg1) |
1363 			       RCANFD_CFG_BRP(brp) |
1364 			       RCANFD_CFG_SJW(sjw) |
1365 			       RCANFD_CFG_TSEG2(tseg2));
1366 		}
1367 
1368 		rcar_canfd_write(priv->base, RCANFD_CCFG(ch), cfg);
1369 		netdev_dbg(priv->ndev,
1370 			   "rate: brp %u, sjw %u, tseg1 %u, tseg2 %u\n",
1371 			   brp, sjw, tseg1, tseg2);
1372 	}
1373 }
1374 
1375 static int rcar_canfd_start(struct net_device *ndev)
1376 {
1377 	struct rcar_canfd_channel *priv = netdev_priv(ndev);
1378 	struct rcar_canfd_global *gpriv = priv->gpriv;
1379 	int err = -EOPNOTSUPP;
1380 	u32 sts, ch = priv->channel;
1381 	u32 ridx = ch + RCANFD_RFFIFO_IDX;
1382 
1383 	rcar_canfd_set_bittiming(ndev);
1384 
1385 	rcar_canfd_enable_channel_interrupts(priv);
1386 
1387 	/* Set channel to Operational mode */
1388 	rcar_canfd_update_bit(priv->base, RCANFD_CCTR(ch),
1389 			      RCANFD_CCTR_CHMDC_MASK, RCANFD_CCTR_CHDMC_COPM);
1390 
1391 	/* Verify channel mode change */
1392 	err = readl_poll_timeout((priv->base + RCANFD_CSTS(ch)), sts,
1393 				 (sts & RCANFD_CSTS_COMSTS), 2, 500000);
1394 	if (err) {
1395 		netdev_err(ndev, "channel %u communication state failed\n", ch);
1396 		goto fail_mode_change;
1397 	}
1398 
1399 	/* Enable Common & Rx FIFO */
1400 	rcar_canfd_set_bit(priv->base, RCANFD_CFCC(gpriv, ch, RCANFD_CFFIFO_IDX),
1401 			   RCANFD_CFCC_CFE);
1402 	rcar_canfd_set_bit(priv->base, RCANFD_RFCC(gpriv, ridx), RCANFD_RFCC_RFE);
1403 
1404 	priv->can.state = CAN_STATE_ERROR_ACTIVE;
1405 	return 0;
1406 
1407 fail_mode_change:
1408 	rcar_canfd_disable_channel_interrupts(priv);
1409 	return err;
1410 }
1411 
1412 static int rcar_canfd_open(struct net_device *ndev)
1413 {
1414 	struct rcar_canfd_channel *priv = netdev_priv(ndev);
1415 	struct rcar_canfd_global *gpriv = priv->gpriv;
1416 	int err;
1417 
1418 	err = phy_power_on(priv->transceiver);
1419 	if (err) {
1420 		netdev_err(ndev, "failed to power on PHY: %pe\n", ERR_PTR(err));
1421 		return err;
1422 	}
1423 
1424 	/* Peripheral clock is already enabled in probe */
1425 	err = clk_prepare_enable(gpriv->can_clk);
1426 	if (err) {
1427 		netdev_err(ndev, "failed to enable CAN clock: %pe\n", ERR_PTR(err));
1428 		goto out_phy;
1429 	}
1430 
1431 	err = open_candev(ndev);
1432 	if (err) {
1433 		netdev_err(ndev, "open_candev() failed: %pe\n", ERR_PTR(err));
1434 		goto out_can_clock;
1435 	}
1436 
1437 	napi_enable(&priv->napi);
1438 	err = rcar_canfd_start(ndev);
1439 	if (err)
1440 		goto out_close;
1441 	netif_start_queue(ndev);
1442 	return 0;
1443 out_close:
1444 	napi_disable(&priv->napi);
1445 	close_candev(ndev);
1446 out_can_clock:
1447 	clk_disable_unprepare(gpriv->can_clk);
1448 out_phy:
1449 	phy_power_off(priv->transceiver);
1450 	return err;
1451 }
1452 
1453 static void rcar_canfd_stop(struct net_device *ndev)
1454 {
1455 	struct rcar_canfd_channel *priv = netdev_priv(ndev);
1456 	struct rcar_canfd_global *gpriv = priv->gpriv;
1457 	int err;
1458 	u32 sts, ch = priv->channel;
1459 	u32 ridx = ch + RCANFD_RFFIFO_IDX;
1460 
1461 	/* Transition to channel reset mode  */
1462 	rcar_canfd_update_bit(priv->base, RCANFD_CCTR(ch),
1463 			      RCANFD_CCTR_CHMDC_MASK, RCANFD_CCTR_CHDMC_CRESET);
1464 
1465 	/* Check Channel reset mode */
1466 	err = readl_poll_timeout((priv->base + RCANFD_CSTS(ch)), sts,
1467 				 (sts & RCANFD_CSTS_CRSTSTS), 2, 500000);
1468 	if (err)
1469 		netdev_err(ndev, "channel %u reset failed\n", ch);
1470 
1471 	rcar_canfd_disable_channel_interrupts(priv);
1472 
1473 	/* Disable Common & Rx FIFO */
1474 	rcar_canfd_clear_bit(priv->base, RCANFD_CFCC(gpriv, ch, RCANFD_CFFIFO_IDX),
1475 			     RCANFD_CFCC_CFE);
1476 	rcar_canfd_clear_bit(priv->base, RCANFD_RFCC(gpriv, ridx), RCANFD_RFCC_RFE);
1477 
1478 	/* Set the state as STOPPED */
1479 	priv->can.state = CAN_STATE_STOPPED;
1480 }
1481 
1482 static int rcar_canfd_close(struct net_device *ndev)
1483 {
1484 	struct rcar_canfd_channel *priv = netdev_priv(ndev);
1485 	struct rcar_canfd_global *gpriv = priv->gpriv;
1486 
1487 	netif_stop_queue(ndev);
1488 	rcar_canfd_stop(ndev);
1489 	napi_disable(&priv->napi);
1490 	clk_disable_unprepare(gpriv->can_clk);
1491 	close_candev(ndev);
1492 	phy_power_off(priv->transceiver);
1493 	return 0;
1494 }
1495 
1496 static netdev_tx_t rcar_canfd_start_xmit(struct sk_buff *skb,
1497 					 struct net_device *ndev)
1498 {
1499 	struct rcar_canfd_channel *priv = netdev_priv(ndev);
1500 	struct rcar_canfd_global *gpriv = priv->gpriv;
1501 	struct canfd_frame *cf = (struct canfd_frame *)skb->data;
1502 	u32 sts = 0, id, dlc;
1503 	unsigned long flags;
1504 	u32 ch = priv->channel;
1505 
1506 	if (can_dev_dropped_skb(ndev, skb))
1507 		return NETDEV_TX_OK;
1508 
1509 	if (cf->can_id & CAN_EFF_FLAG) {
1510 		id = cf->can_id & CAN_EFF_MASK;
1511 		id |= RCANFD_CFID_CFIDE;
1512 	} else {
1513 		id = cf->can_id & CAN_SFF_MASK;
1514 	}
1515 
1516 	if (cf->can_id & CAN_RTR_FLAG)
1517 		id |= RCANFD_CFID_CFRTR;
1518 
1519 	dlc = RCANFD_CFPTR_CFDLC(can_fd_len2dlc(cf->len));
1520 
1521 	if ((priv->can.ctrlmode & CAN_CTRLMODE_FD) || is_gen4(gpriv)) {
1522 		rcar_canfd_write(priv->base,
1523 				 RCANFD_F_CFID(gpriv, ch, RCANFD_CFFIFO_IDX), id);
1524 		rcar_canfd_write(priv->base,
1525 				 RCANFD_F_CFPTR(gpriv, ch, RCANFD_CFFIFO_IDX), dlc);
1526 
1527 		if (can_is_canfd_skb(skb)) {
1528 			/* CAN FD frame format */
1529 			sts |= RCANFD_CFFDCSTS_CFFDF;
1530 			if (cf->flags & CANFD_BRS)
1531 				sts |= RCANFD_CFFDCSTS_CFBRS;
1532 
1533 			if (priv->can.state == CAN_STATE_ERROR_PASSIVE)
1534 				sts |= RCANFD_CFFDCSTS_CFESI;
1535 		}
1536 
1537 		rcar_canfd_write(priv->base,
1538 				 RCANFD_F_CFFDCSTS(gpriv, ch, RCANFD_CFFIFO_IDX), sts);
1539 
1540 		rcar_canfd_put_data(priv, cf,
1541 				    RCANFD_F_CFDF(gpriv, ch, RCANFD_CFFIFO_IDX, 0));
1542 	} else {
1543 		rcar_canfd_write(priv->base,
1544 				 RCANFD_C_CFID(ch, RCANFD_CFFIFO_IDX), id);
1545 		rcar_canfd_write(priv->base,
1546 				 RCANFD_C_CFPTR(ch, RCANFD_CFFIFO_IDX), dlc);
1547 		rcar_canfd_put_data(priv, cf,
1548 				    RCANFD_C_CFDF(ch, RCANFD_CFFIFO_IDX, 0));
1549 	}
1550 
1551 	can_put_echo_skb(skb, ndev, priv->tx_head % RCANFD_FIFO_DEPTH, 0);
1552 
1553 	spin_lock_irqsave(&priv->tx_lock, flags);
1554 	priv->tx_head++;
1555 
1556 	/* Stop the queue if we've filled all FIFO entries */
1557 	if (priv->tx_head - priv->tx_tail >= RCANFD_FIFO_DEPTH)
1558 		netif_stop_queue(ndev);
1559 
1560 	/* Start Tx: Write 0xff to CFPC to increment the CPU-side
1561 	 * pointer for the Common FIFO
1562 	 */
1563 	rcar_canfd_write(priv->base,
1564 			 RCANFD_CFPCTR(gpriv, ch, RCANFD_CFFIFO_IDX), 0xff);
1565 
1566 	spin_unlock_irqrestore(&priv->tx_lock, flags);
1567 	return NETDEV_TX_OK;
1568 }
1569 
1570 static void rcar_canfd_rx_pkt(struct rcar_canfd_channel *priv)
1571 {
1572 	struct net_device_stats *stats = &priv->ndev->stats;
1573 	struct rcar_canfd_global *gpriv = priv->gpriv;
1574 	struct canfd_frame *cf;
1575 	struct sk_buff *skb;
1576 	u32 sts = 0, id, dlc;
1577 	u32 ch = priv->channel;
1578 	u32 ridx = ch + RCANFD_RFFIFO_IDX;
1579 
1580 	if ((priv->can.ctrlmode & CAN_CTRLMODE_FD) || is_gen4(gpriv)) {
1581 		id = rcar_canfd_read(priv->base, RCANFD_F_RFID(gpriv, ridx));
1582 		dlc = rcar_canfd_read(priv->base, RCANFD_F_RFPTR(gpriv, ridx));
1583 
1584 		sts = rcar_canfd_read(priv->base, RCANFD_F_RFFDSTS(gpriv, ridx));
1585 
1586 		if ((priv->can.ctrlmode & CAN_CTRLMODE_FD) &&
1587 		    sts & RCANFD_RFFDSTS_RFFDF)
1588 			skb = alloc_canfd_skb(priv->ndev, &cf);
1589 		else
1590 			skb = alloc_can_skb(priv->ndev,
1591 					    (struct can_frame **)&cf);
1592 	} else {
1593 		id = rcar_canfd_read(priv->base, RCANFD_C_RFID(ridx));
1594 		dlc = rcar_canfd_read(priv->base, RCANFD_C_RFPTR(ridx));
1595 		skb = alloc_can_skb(priv->ndev, (struct can_frame **)&cf);
1596 	}
1597 
1598 	if (!skb) {
1599 		stats->rx_dropped++;
1600 		return;
1601 	}
1602 
1603 	if (id & RCANFD_RFID_RFIDE)
1604 		cf->can_id = (id & CAN_EFF_MASK) | CAN_EFF_FLAG;
1605 	else
1606 		cf->can_id = id & CAN_SFF_MASK;
1607 
1608 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
1609 		if (sts & RCANFD_RFFDSTS_RFFDF)
1610 			cf->len = can_fd_dlc2len(RCANFD_RFPTR_RFDLC(dlc));
1611 		else
1612 			cf->len = can_cc_dlc2len(RCANFD_RFPTR_RFDLC(dlc));
1613 
1614 		if (sts & RCANFD_RFFDSTS_RFESI) {
1615 			cf->flags |= CANFD_ESI;
1616 			netdev_dbg(priv->ndev, "ESI Error\n");
1617 		}
1618 
1619 		if (!(sts & RCANFD_RFFDSTS_RFFDF) && (id & RCANFD_RFID_RFRTR)) {
1620 			cf->can_id |= CAN_RTR_FLAG;
1621 		} else {
1622 			if (sts & RCANFD_RFFDSTS_RFBRS)
1623 				cf->flags |= CANFD_BRS;
1624 
1625 			rcar_canfd_get_data(priv, cf, RCANFD_F_RFDF(gpriv, ridx, 0));
1626 		}
1627 	} else {
1628 		cf->len = can_cc_dlc2len(RCANFD_RFPTR_RFDLC(dlc));
1629 		if (id & RCANFD_RFID_RFRTR)
1630 			cf->can_id |= CAN_RTR_FLAG;
1631 		else if (is_gen4(gpriv))
1632 			rcar_canfd_get_data(priv, cf, RCANFD_F_RFDF(gpriv, ridx, 0));
1633 		else
1634 			rcar_canfd_get_data(priv, cf, RCANFD_C_RFDF(ridx, 0));
1635 	}
1636 
1637 	/* Write 0xff to RFPC to increment the CPU-side
1638 	 * pointer of the Rx FIFO
1639 	 */
1640 	rcar_canfd_write(priv->base, RCANFD_RFPCTR(gpriv, ridx), 0xff);
1641 
1642 	if (!(cf->can_id & CAN_RTR_FLAG))
1643 		stats->rx_bytes += cf->len;
1644 	stats->rx_packets++;
1645 	netif_receive_skb(skb);
1646 }
1647 
1648 static int rcar_canfd_rx_poll(struct napi_struct *napi, int quota)
1649 {
1650 	struct rcar_canfd_channel *priv =
1651 		container_of(napi, struct rcar_canfd_channel, napi);
1652 	struct rcar_canfd_global *gpriv = priv->gpriv;
1653 	int num_pkts;
1654 	u32 sts;
1655 	u32 ch = priv->channel;
1656 	u32 ridx = ch + RCANFD_RFFIFO_IDX;
1657 
1658 	for (num_pkts = 0; num_pkts < quota; num_pkts++) {
1659 		sts = rcar_canfd_read(priv->base, RCANFD_RFSTS(gpriv, ridx));
1660 		/* Check FIFO empty condition */
1661 		if (sts & RCANFD_RFSTS_RFEMP)
1662 			break;
1663 
1664 		rcar_canfd_rx_pkt(priv);
1665 
1666 		/* Clear interrupt bit */
1667 		if (sts & RCANFD_RFSTS_RFIF)
1668 			rcar_canfd_write(priv->base, RCANFD_RFSTS(gpriv, ridx),
1669 					 sts & ~RCANFD_RFSTS_RFIF);
1670 	}
1671 
1672 	/* All packets processed */
1673 	if (num_pkts < quota) {
1674 		if (napi_complete_done(napi, num_pkts)) {
1675 			/* Enable Rx FIFO interrupts */
1676 			rcar_canfd_set_bit(priv->base, RCANFD_RFCC(gpriv, ridx),
1677 					   RCANFD_RFCC_RFIE);
1678 		}
1679 	}
1680 	return num_pkts;
1681 }
1682 
1683 static int rcar_canfd_do_set_mode(struct net_device *ndev, enum can_mode mode)
1684 {
1685 	int err;
1686 
1687 	switch (mode) {
1688 	case CAN_MODE_START:
1689 		err = rcar_canfd_start(ndev);
1690 		if (err)
1691 			return err;
1692 		netif_wake_queue(ndev);
1693 		return 0;
1694 	default:
1695 		return -EOPNOTSUPP;
1696 	}
1697 }
1698 
1699 static int rcar_canfd_get_berr_counter(const struct net_device *dev,
1700 				       struct can_berr_counter *bec)
1701 {
1702 	struct rcar_canfd_channel *priv = netdev_priv(dev);
1703 	u32 val, ch = priv->channel;
1704 
1705 	/* Peripheral clock is already enabled in probe */
1706 	val = rcar_canfd_read(priv->base, RCANFD_CSTS(ch));
1707 	bec->txerr = RCANFD_CSTS_TECCNT(val);
1708 	bec->rxerr = RCANFD_CSTS_RECCNT(val);
1709 	return 0;
1710 }
1711 
1712 static const struct net_device_ops rcar_canfd_netdev_ops = {
1713 	.ndo_open = rcar_canfd_open,
1714 	.ndo_stop = rcar_canfd_close,
1715 	.ndo_start_xmit = rcar_canfd_start_xmit,
1716 	.ndo_change_mtu = can_change_mtu,
1717 };
1718 
1719 static const struct ethtool_ops rcar_canfd_ethtool_ops = {
1720 	.get_ts_info = ethtool_op_get_ts_info,
1721 };
1722 
1723 static int rcar_canfd_channel_probe(struct rcar_canfd_global *gpriv, u32 ch,
1724 				    u32 fcan_freq, struct phy *transceiver)
1725 {
1726 	const struct rcar_canfd_hw_info *info = gpriv->info;
1727 	struct platform_device *pdev = gpriv->pdev;
1728 	struct device *dev = &pdev->dev;
1729 	struct rcar_canfd_channel *priv;
1730 	struct net_device *ndev;
1731 	int err = -ENODEV;
1732 
1733 	ndev = alloc_candev(sizeof(*priv), RCANFD_FIFO_DEPTH);
1734 	if (!ndev)
1735 		return -ENOMEM;
1736 
1737 	priv = netdev_priv(ndev);
1738 
1739 	ndev->netdev_ops = &rcar_canfd_netdev_ops;
1740 	ndev->ethtool_ops = &rcar_canfd_ethtool_ops;
1741 	ndev->flags |= IFF_ECHO;
1742 	priv->ndev = ndev;
1743 	priv->base = gpriv->base;
1744 	priv->transceiver = transceiver;
1745 	priv->channel = ch;
1746 	priv->gpriv = gpriv;
1747 	if (transceiver)
1748 		priv->can.bitrate_max = transceiver->attrs.max_link_rate;
1749 	priv->can.clock.freq = fcan_freq;
1750 	dev_info(dev, "can_clk rate is %u\n", priv->can.clock.freq);
1751 
1752 	if (info->multi_channel_irqs) {
1753 		char *irq_name;
1754 		int err_irq;
1755 		int tx_irq;
1756 
1757 		err_irq = platform_get_irq_byname(pdev, ch == 0 ? "ch0_err" : "ch1_err");
1758 		if (err_irq < 0) {
1759 			err = err_irq;
1760 			goto fail;
1761 		}
1762 
1763 		tx_irq = platform_get_irq_byname(pdev, ch == 0 ? "ch0_trx" : "ch1_trx");
1764 		if (tx_irq < 0) {
1765 			err = tx_irq;
1766 			goto fail;
1767 		}
1768 
1769 		irq_name = devm_kasprintf(dev, GFP_KERNEL, "canfd.ch%d_err",
1770 					  ch);
1771 		if (!irq_name) {
1772 			err = -ENOMEM;
1773 			goto fail;
1774 		}
1775 		err = devm_request_irq(dev, err_irq,
1776 				       rcar_canfd_channel_err_interrupt, 0,
1777 				       irq_name, priv);
1778 		if (err) {
1779 			dev_err(dev, "devm_request_irq CH Err %d failed: %pe\n",
1780 				err_irq, ERR_PTR(err));
1781 			goto fail;
1782 		}
1783 		irq_name = devm_kasprintf(dev, GFP_KERNEL, "canfd.ch%d_trx",
1784 					  ch);
1785 		if (!irq_name) {
1786 			err = -ENOMEM;
1787 			goto fail;
1788 		}
1789 		err = devm_request_irq(dev, tx_irq,
1790 				       rcar_canfd_channel_tx_interrupt, 0,
1791 				       irq_name, priv);
1792 		if (err) {
1793 			dev_err(dev, "devm_request_irq Tx %d failed: %pe\n",
1794 				tx_irq, ERR_PTR(err));
1795 			goto fail;
1796 		}
1797 	}
1798 
1799 	if (gpriv->fdmode) {
1800 		priv->can.bittiming_const = &rcar_canfd_nom_bittiming_const;
1801 		priv->can.data_bittiming_const =
1802 			&rcar_canfd_data_bittiming_const;
1803 
1804 		/* Controller starts in CAN FD only mode */
1805 		err = can_set_static_ctrlmode(ndev, CAN_CTRLMODE_FD);
1806 		if (err)
1807 			goto fail;
1808 		priv->can.ctrlmode_supported = CAN_CTRLMODE_BERR_REPORTING;
1809 	} else {
1810 		/* Controller starts in Classical CAN only mode */
1811 		priv->can.bittiming_const = &rcar_canfd_bittiming_const;
1812 		priv->can.ctrlmode_supported = CAN_CTRLMODE_BERR_REPORTING;
1813 	}
1814 
1815 	priv->can.do_set_mode = rcar_canfd_do_set_mode;
1816 	priv->can.do_get_berr_counter = rcar_canfd_get_berr_counter;
1817 	SET_NETDEV_DEV(ndev, dev);
1818 
1819 	netif_napi_add_weight(ndev, &priv->napi, rcar_canfd_rx_poll,
1820 			      RCANFD_NAPI_WEIGHT);
1821 	spin_lock_init(&priv->tx_lock);
1822 	gpriv->ch[priv->channel] = priv;
1823 	err = register_candev(ndev);
1824 	if (err) {
1825 		dev_err(dev, "register_candev() failed: %pe\n", ERR_PTR(err));
1826 		goto fail_candev;
1827 	}
1828 	dev_info(dev, "device registered (channel %u)\n", priv->channel);
1829 	return 0;
1830 
1831 fail_candev:
1832 	netif_napi_del(&priv->napi);
1833 fail:
1834 	free_candev(ndev);
1835 	return err;
1836 }
1837 
1838 static void rcar_canfd_channel_remove(struct rcar_canfd_global *gpriv, u32 ch)
1839 {
1840 	struct rcar_canfd_channel *priv = gpriv->ch[ch];
1841 
1842 	if (priv) {
1843 		unregister_candev(priv->ndev);
1844 		netif_napi_del(&priv->napi);
1845 		free_candev(priv->ndev);
1846 	}
1847 }
1848 
1849 static int rcar_canfd_probe(struct platform_device *pdev)
1850 {
1851 	struct phy *transceivers[RCANFD_NUM_CHANNELS] = { NULL, };
1852 	const struct rcar_canfd_hw_info *info;
1853 	struct device *dev = &pdev->dev;
1854 	void __iomem *addr;
1855 	u32 sts, ch, fcan_freq;
1856 	struct rcar_canfd_global *gpriv;
1857 	struct device_node *of_child;
1858 	unsigned long channels_mask = 0;
1859 	int err, ch_irq, g_irq;
1860 	int g_err_irq, g_recc_irq;
1861 	bool fdmode = true;			/* CAN FD only mode - default */
1862 	char name[9] = "channelX";
1863 	int i;
1864 
1865 	info = of_device_get_match_data(dev);
1866 
1867 	if (of_property_read_bool(dev->of_node, "renesas,no-can-fd"))
1868 		fdmode = false;			/* Classical CAN only mode */
1869 
1870 	for (i = 0; i < info->max_channels; ++i) {
1871 		name[7] = '0' + i;
1872 		of_child = of_get_child_by_name(dev->of_node, name);
1873 		if (of_child && of_device_is_available(of_child)) {
1874 			channels_mask |= BIT(i);
1875 			transceivers[i] = devm_of_phy_optional_get(dev,
1876 							of_child, NULL);
1877 		}
1878 		of_node_put(of_child);
1879 		if (IS_ERR(transceivers[i]))
1880 			return PTR_ERR(transceivers[i]);
1881 	}
1882 
1883 	if (info->shared_global_irqs) {
1884 		ch_irq = platform_get_irq_byname_optional(pdev, "ch_int");
1885 		if (ch_irq < 0) {
1886 			/* For backward compatibility get irq by index */
1887 			ch_irq = platform_get_irq(pdev, 0);
1888 			if (ch_irq < 0)
1889 				return ch_irq;
1890 		}
1891 
1892 		g_irq = platform_get_irq_byname_optional(pdev, "g_int");
1893 		if (g_irq < 0) {
1894 			/* For backward compatibility get irq by index */
1895 			g_irq = platform_get_irq(pdev, 1);
1896 			if (g_irq < 0)
1897 				return g_irq;
1898 		}
1899 	} else {
1900 		g_err_irq = platform_get_irq_byname(pdev, "g_err");
1901 		if (g_err_irq < 0)
1902 			return g_err_irq;
1903 
1904 		g_recc_irq = platform_get_irq_byname(pdev, "g_recc");
1905 		if (g_recc_irq < 0)
1906 			return g_recc_irq;
1907 	}
1908 
1909 	/* Global controller context */
1910 	gpriv = devm_kzalloc(dev, sizeof(*gpriv), GFP_KERNEL);
1911 	if (!gpriv)
1912 		return -ENOMEM;
1913 
1914 	gpriv->pdev = pdev;
1915 	gpriv->channels_mask = channels_mask;
1916 	gpriv->fdmode = fdmode;
1917 	gpriv->info = info;
1918 
1919 	gpriv->rstc1 = devm_reset_control_get_optional_exclusive(dev, "rstp_n");
1920 	if (IS_ERR(gpriv->rstc1))
1921 		return dev_err_probe(dev, PTR_ERR(gpriv->rstc1),
1922 				     "failed to get rstp_n\n");
1923 
1924 	gpriv->rstc2 = devm_reset_control_get_optional_exclusive(dev, "rstc_n");
1925 	if (IS_ERR(gpriv->rstc2))
1926 		return dev_err_probe(dev, PTR_ERR(gpriv->rstc2),
1927 				     "failed to get rstc_n\n");
1928 
1929 	/* Peripheral clock */
1930 	gpriv->clkp = devm_clk_get(dev, "fck");
1931 	if (IS_ERR(gpriv->clkp))
1932 		return dev_err_probe(dev, PTR_ERR(gpriv->clkp),
1933 				     "cannot get peripheral clock\n");
1934 
1935 	/* fCAN clock: Pick External clock. If not available fallback to
1936 	 * CANFD clock
1937 	 */
1938 	gpriv->can_clk = devm_clk_get(dev, "can_clk");
1939 	if (IS_ERR(gpriv->can_clk) || (clk_get_rate(gpriv->can_clk) == 0)) {
1940 		gpriv->can_clk = devm_clk_get(dev, "canfd");
1941 		if (IS_ERR(gpriv->can_clk))
1942 			return dev_err_probe(dev, PTR_ERR(gpriv->can_clk),
1943 					     "cannot get canfd clock\n");
1944 
1945 		gpriv->fcan = RCANFD_CANFDCLK;
1946 
1947 	} else {
1948 		gpriv->fcan = RCANFD_EXTCLK;
1949 	}
1950 	fcan_freq = clk_get_rate(gpriv->can_clk);
1951 
1952 	if (gpriv->fcan == RCANFD_CANFDCLK)
1953 		/* CANFD clock is further divided by (1/2) within the IP */
1954 		fcan_freq /= info->postdiv;
1955 
1956 	addr = devm_platform_ioremap_resource(pdev, 0);
1957 	if (IS_ERR(addr)) {
1958 		err = PTR_ERR(addr);
1959 		goto fail_dev;
1960 	}
1961 	gpriv->base = addr;
1962 
1963 	/* Request IRQ that's common for both channels */
1964 	if (info->shared_global_irqs) {
1965 		err = devm_request_irq(dev, ch_irq,
1966 				       rcar_canfd_channel_interrupt, 0,
1967 				       "canfd.ch_int", gpriv);
1968 		if (err) {
1969 			dev_err(dev, "devm_request_irq %d failed: %pe\n",
1970 				ch_irq, ERR_PTR(err));
1971 			goto fail_dev;
1972 		}
1973 
1974 		err = devm_request_irq(dev, g_irq, rcar_canfd_global_interrupt,
1975 				       0, "canfd.g_int", gpriv);
1976 		if (err) {
1977 			dev_err(dev, "devm_request_irq %d failed: %pe\n",
1978 				g_irq, ERR_PTR(err));
1979 			goto fail_dev;
1980 		}
1981 	} else {
1982 		err = devm_request_irq(dev, g_recc_irq,
1983 				       rcar_canfd_global_receive_fifo_interrupt, 0,
1984 				       "canfd.g_recc", gpriv);
1985 
1986 		if (err) {
1987 			dev_err(dev, "devm_request_irq %d failed: %pe\n",
1988 				g_recc_irq, ERR_PTR(err));
1989 			goto fail_dev;
1990 		}
1991 
1992 		err = devm_request_irq(dev, g_err_irq,
1993 				       rcar_canfd_global_err_interrupt, 0,
1994 				       "canfd.g_err", gpriv);
1995 		if (err) {
1996 			dev_err(dev, "devm_request_irq %d failed: %pe\n",
1997 				g_err_irq, ERR_PTR(err));
1998 			goto fail_dev;
1999 		}
2000 	}
2001 
2002 	err = reset_control_reset(gpriv->rstc1);
2003 	if (err)
2004 		goto fail_dev;
2005 	err = reset_control_reset(gpriv->rstc2);
2006 	if (err) {
2007 		reset_control_assert(gpriv->rstc1);
2008 		goto fail_dev;
2009 	}
2010 
2011 	/* Enable peripheral clock for register access */
2012 	err = clk_prepare_enable(gpriv->clkp);
2013 	if (err) {
2014 		dev_err(dev, "failed to enable peripheral clock: %pe\n",
2015 			ERR_PTR(err));
2016 		goto fail_reset;
2017 	}
2018 
2019 	err = rcar_canfd_reset_controller(gpriv);
2020 	if (err) {
2021 		dev_err(dev, "reset controller failed: %pe\n", ERR_PTR(err));
2022 		goto fail_clk;
2023 	}
2024 
2025 	/* Controller in Global reset & Channel reset mode */
2026 	rcar_canfd_configure_controller(gpriv);
2027 
2028 	/* Configure per channel attributes */
2029 	for_each_set_bit(ch, &gpriv->channels_mask, info->max_channels) {
2030 		/* Configure Channel's Rx fifo */
2031 		rcar_canfd_configure_rx(gpriv, ch);
2032 
2033 		/* Configure Channel's Tx (Common) fifo */
2034 		rcar_canfd_configure_tx(gpriv, ch);
2035 
2036 		/* Configure receive rules */
2037 		rcar_canfd_configure_afl_rules(gpriv, ch);
2038 	}
2039 
2040 	/* Configure common interrupts */
2041 	rcar_canfd_enable_global_interrupts(gpriv);
2042 
2043 	/* Start Global operation mode */
2044 	rcar_canfd_update_bit(gpriv->base, RCANFD_GCTR, RCANFD_GCTR_GMDC_MASK,
2045 			      RCANFD_GCTR_GMDC_GOPM);
2046 
2047 	/* Verify mode change */
2048 	err = readl_poll_timeout((gpriv->base + RCANFD_GSTS), sts,
2049 				 !(sts & RCANFD_GSTS_GNOPM), 2, 500000);
2050 	if (err) {
2051 		dev_err(dev, "global operational mode failed\n");
2052 		goto fail_mode;
2053 	}
2054 
2055 	for_each_set_bit(ch, &gpriv->channels_mask, info->max_channels) {
2056 		err = rcar_canfd_channel_probe(gpriv, ch, fcan_freq,
2057 					       transceivers[ch]);
2058 		if (err)
2059 			goto fail_channel;
2060 	}
2061 
2062 	platform_set_drvdata(pdev, gpriv);
2063 	dev_info(dev, "global operational state (clk %d, fdmode %d)\n",
2064 		 gpriv->fcan, gpriv->fdmode);
2065 	return 0;
2066 
2067 fail_channel:
2068 	for_each_set_bit(ch, &gpriv->channels_mask, info->max_channels)
2069 		rcar_canfd_channel_remove(gpriv, ch);
2070 fail_mode:
2071 	rcar_canfd_disable_global_interrupts(gpriv);
2072 fail_clk:
2073 	clk_disable_unprepare(gpriv->clkp);
2074 fail_reset:
2075 	reset_control_assert(gpriv->rstc1);
2076 	reset_control_assert(gpriv->rstc2);
2077 fail_dev:
2078 	return err;
2079 }
2080 
2081 static int rcar_canfd_remove(struct platform_device *pdev)
2082 {
2083 	struct rcar_canfd_global *gpriv = platform_get_drvdata(pdev);
2084 	u32 ch;
2085 
2086 	rcar_canfd_reset_controller(gpriv);
2087 	rcar_canfd_disable_global_interrupts(gpriv);
2088 
2089 	for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) {
2090 		rcar_canfd_disable_channel_interrupts(gpriv->ch[ch]);
2091 		rcar_canfd_channel_remove(gpriv, ch);
2092 	}
2093 
2094 	/* Enter global sleep mode */
2095 	rcar_canfd_set_bit(gpriv->base, RCANFD_GCTR, RCANFD_GCTR_GSLPR);
2096 	clk_disable_unprepare(gpriv->clkp);
2097 	reset_control_assert(gpriv->rstc1);
2098 	reset_control_assert(gpriv->rstc2);
2099 
2100 	return 0;
2101 }
2102 
2103 static int __maybe_unused rcar_canfd_suspend(struct device *dev)
2104 {
2105 	return 0;
2106 }
2107 
2108 static int __maybe_unused rcar_canfd_resume(struct device *dev)
2109 {
2110 	return 0;
2111 }
2112 
2113 static SIMPLE_DEV_PM_OPS(rcar_canfd_pm_ops, rcar_canfd_suspend,
2114 			 rcar_canfd_resume);
2115 
2116 static const __maybe_unused struct of_device_id rcar_canfd_of_table[] = {
2117 	{ .compatible = "renesas,r8a779a0-canfd", .data = &rcar_gen4_hw_info },
2118 	{ .compatible = "renesas,rcar-gen3-canfd", .data = &rcar_gen3_hw_info },
2119 	{ .compatible = "renesas,rcar-gen4-canfd", .data = &rcar_gen4_hw_info },
2120 	{ .compatible = "renesas,rzg2l-canfd", .data = &rzg2l_hw_info },
2121 	{ }
2122 };
2123 
2124 MODULE_DEVICE_TABLE(of, rcar_canfd_of_table);
2125 
2126 static struct platform_driver rcar_canfd_driver = {
2127 	.driver = {
2128 		.name = RCANFD_DRV_NAME,
2129 		.of_match_table = of_match_ptr(rcar_canfd_of_table),
2130 		.pm = &rcar_canfd_pm_ops,
2131 	},
2132 	.probe = rcar_canfd_probe,
2133 	.remove = rcar_canfd_remove,
2134 };
2135 
2136 module_platform_driver(rcar_canfd_driver);
2137 
2138 MODULE_AUTHOR("Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>");
2139 MODULE_LICENSE("GPL");
2140 MODULE_DESCRIPTION("CAN FD driver for Renesas R-Car SoC");
2141 MODULE_ALIAS("platform:" RCANFD_DRV_NAME);
2142