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