• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (C) 1999 - 2010 Intel Corporation.
3  * Copyright (C) 2010 LAPIS SEMICONDUCTOR CO., LTD.
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; version 2 of the License.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, see <http://www.gnu.org/licenses/>.
16  */
17 
18 #include <linux/interrupt.h>
19 #include <linux/delay.h>
20 #include <linux/io.h>
21 #include <linux/module.h>
22 #include <linux/sched.h>
23 #include <linux/pci.h>
24 #include <linux/kernel.h>
25 #include <linux/types.h>
26 #include <linux/errno.h>
27 #include <linux/netdevice.h>
28 #include <linux/skbuff.h>
29 #include <linux/can.h>
30 #include <linux/can/dev.h>
31 #include <linux/can/error.h>
32 
33 #define PCH_CTRL_INIT		BIT(0) /* The INIT bit of CANCONT register. */
34 #define PCH_CTRL_IE		BIT(1) /* The IE bit of CAN control register */
35 #define PCH_CTRL_IE_SIE_EIE	(BIT(3) | BIT(2) | BIT(1))
36 #define PCH_CTRL_CCE		BIT(6)
37 #define PCH_CTRL_OPT		BIT(7) /* The OPT bit of CANCONT register. */
38 #define PCH_OPT_SILENT		BIT(3) /* The Silent bit of CANOPT reg. */
39 #define PCH_OPT_LBACK		BIT(4) /* The LoopBack bit of CANOPT reg. */
40 
41 #define PCH_CMASK_RX_TX_SET	0x00f3
42 #define PCH_CMASK_RX_TX_GET	0x0073
43 #define PCH_CMASK_ALL		0xff
44 #define PCH_CMASK_NEWDAT	BIT(2)
45 #define PCH_CMASK_CLRINTPND	BIT(3)
46 #define PCH_CMASK_CTRL		BIT(4)
47 #define PCH_CMASK_ARB		BIT(5)
48 #define PCH_CMASK_MASK		BIT(6)
49 #define PCH_CMASK_RDWR		BIT(7)
50 #define PCH_IF_MCONT_NEWDAT	BIT(15)
51 #define PCH_IF_MCONT_MSGLOST	BIT(14)
52 #define PCH_IF_MCONT_INTPND	BIT(13)
53 #define PCH_IF_MCONT_UMASK	BIT(12)
54 #define PCH_IF_MCONT_TXIE	BIT(11)
55 #define PCH_IF_MCONT_RXIE	BIT(10)
56 #define PCH_IF_MCONT_RMTEN	BIT(9)
57 #define PCH_IF_MCONT_TXRQXT	BIT(8)
58 #define PCH_IF_MCONT_EOB	BIT(7)
59 #define PCH_IF_MCONT_DLC	(BIT(0) | BIT(1) | BIT(2) | BIT(3))
60 #define PCH_MASK2_MDIR_MXTD	(BIT(14) | BIT(15))
61 #define PCH_ID2_DIR		BIT(13)
62 #define PCH_ID2_XTD		BIT(14)
63 #define PCH_ID_MSGVAL		BIT(15)
64 #define PCH_IF_CREQ_BUSY	BIT(15)
65 
66 #define PCH_STATUS_INT		0x8000
67 #define PCH_RP			0x00008000
68 #define PCH_REC			0x00007f00
69 #define PCH_TEC			0x000000ff
70 
71 #define PCH_TX_OK		BIT(3)
72 #define PCH_RX_OK		BIT(4)
73 #define PCH_EPASSIV		BIT(5)
74 #define PCH_EWARN		BIT(6)
75 #define PCH_BUS_OFF		BIT(7)
76 
77 /* bit position of certain controller bits. */
78 #define PCH_BIT_BRP_SHIFT	0
79 #define PCH_BIT_SJW_SHIFT	6
80 #define PCH_BIT_TSEG1_SHIFT	8
81 #define PCH_BIT_TSEG2_SHIFT	12
82 #define PCH_BIT_BRPE_BRPE_SHIFT	6
83 
84 #define PCH_MSK_BITT_BRP	0x3f
85 #define PCH_MSK_BRPE_BRPE	0x3c0
86 #define PCH_MSK_CTRL_IE_SIE_EIE	0x07
87 #define PCH_COUNTER_LIMIT	10
88 
89 #define PCH_CAN_CLK		50000000	/* 50MHz */
90 
91 /*
92  * Define the number of message object.
93  * PCH CAN communications are done via Message RAM.
94  * The Message RAM consists of 32 message objects.
95  */
96 #define PCH_RX_OBJ_NUM		26
97 #define PCH_TX_OBJ_NUM		6
98 #define PCH_RX_OBJ_START	1
99 #define PCH_RX_OBJ_END		PCH_RX_OBJ_NUM
100 #define PCH_TX_OBJ_START	(PCH_RX_OBJ_END + 1)
101 #define PCH_TX_OBJ_END		(PCH_RX_OBJ_NUM + PCH_TX_OBJ_NUM)
102 
103 #define PCH_FIFO_THRESH		16
104 
105 /* TxRqst2 show status of MsgObjNo.17~32 */
106 #define PCH_TREQ2_TX_MASK	(((1 << PCH_TX_OBJ_NUM) - 1) <<\
107 							(PCH_RX_OBJ_END - 16))
108 
109 enum pch_ifreg {
110 	PCH_RX_IFREG,
111 	PCH_TX_IFREG,
112 };
113 
114 enum pch_can_err {
115 	PCH_STUF_ERR = 1,
116 	PCH_FORM_ERR,
117 	PCH_ACK_ERR,
118 	PCH_BIT1_ERR,
119 	PCH_BIT0_ERR,
120 	PCH_CRC_ERR,
121 	PCH_LEC_ALL,
122 };
123 
124 enum pch_can_mode {
125 	PCH_CAN_ENABLE,
126 	PCH_CAN_DISABLE,
127 	PCH_CAN_ALL,
128 	PCH_CAN_NONE,
129 	PCH_CAN_STOP,
130 	PCH_CAN_RUN,
131 };
132 
133 struct pch_can_if_regs {
134 	u32 creq;
135 	u32 cmask;
136 	u32 mask1;
137 	u32 mask2;
138 	u32 id1;
139 	u32 id2;
140 	u32 mcont;
141 	u32 data[4];
142 	u32 rsv[13];
143 };
144 
145 struct pch_can_regs {
146 	u32 cont;
147 	u32 stat;
148 	u32 errc;
149 	u32 bitt;
150 	u32 intr;
151 	u32 opt;
152 	u32 brpe;
153 	u32 reserve;
154 	struct pch_can_if_regs ifregs[2]; /* [0]=if1  [1]=if2 */
155 	u32 reserve1[8];
156 	u32 treq1;
157 	u32 treq2;
158 	u32 reserve2[6];
159 	u32 data1;
160 	u32 data2;
161 	u32 reserve3[6];
162 	u32 canipend1;
163 	u32 canipend2;
164 	u32 reserve4[6];
165 	u32 canmval1;
166 	u32 canmval2;
167 	u32 reserve5[37];
168 	u32 srst;
169 };
170 
171 struct pch_can_priv {
172 	struct can_priv can;
173 	struct pci_dev *dev;
174 	u32 tx_enable[PCH_TX_OBJ_END];
175 	u32 rx_enable[PCH_TX_OBJ_END];
176 	u32 rx_link[PCH_TX_OBJ_END];
177 	u32 int_enables;
178 	struct net_device *ndev;
179 	struct pch_can_regs __iomem *regs;
180 	struct napi_struct napi;
181 	int tx_obj;	/* Point next Tx Obj index */
182 	int use_msi;
183 };
184 
185 static const struct can_bittiming_const pch_can_bittiming_const = {
186 	.name = KBUILD_MODNAME,
187 	.tseg1_min = 2,
188 	.tseg1_max = 16,
189 	.tseg2_min = 1,
190 	.tseg2_max = 8,
191 	.sjw_max = 4,
192 	.brp_min = 1,
193 	.brp_max = 1024, /* 6bit + extended 4bit */
194 	.brp_inc = 1,
195 };
196 
197 static const struct pci_device_id pch_pci_tbl[] = {
198 	{PCI_VENDOR_ID_INTEL, 0x8818, PCI_ANY_ID, PCI_ANY_ID,},
199 	{0,}
200 };
201 MODULE_DEVICE_TABLE(pci, pch_pci_tbl);
202 
pch_can_bit_set(void __iomem * addr,u32 mask)203 static inline void pch_can_bit_set(void __iomem *addr, u32 mask)
204 {
205 	iowrite32(ioread32(addr) | mask, addr);
206 }
207 
pch_can_bit_clear(void __iomem * addr,u32 mask)208 static inline void pch_can_bit_clear(void __iomem *addr, u32 mask)
209 {
210 	iowrite32(ioread32(addr) & ~mask, addr);
211 }
212 
pch_can_set_run_mode(struct pch_can_priv * priv,enum pch_can_mode mode)213 static void pch_can_set_run_mode(struct pch_can_priv *priv,
214 				 enum pch_can_mode mode)
215 {
216 	switch (mode) {
217 	case PCH_CAN_RUN:
218 		pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_INIT);
219 		break;
220 
221 	case PCH_CAN_STOP:
222 		pch_can_bit_set(&priv->regs->cont, PCH_CTRL_INIT);
223 		break;
224 
225 	default:
226 		netdev_err(priv->ndev, "%s -> Invalid Mode.\n", __func__);
227 		break;
228 	}
229 }
230 
pch_can_set_optmode(struct pch_can_priv * priv)231 static void pch_can_set_optmode(struct pch_can_priv *priv)
232 {
233 	u32 reg_val = ioread32(&priv->regs->opt);
234 
235 	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
236 		reg_val |= PCH_OPT_SILENT;
237 
238 	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
239 		reg_val |= PCH_OPT_LBACK;
240 
241 	pch_can_bit_set(&priv->regs->cont, PCH_CTRL_OPT);
242 	iowrite32(reg_val, &priv->regs->opt);
243 }
244 
pch_can_rw_msg_obj(void __iomem * creq_addr,u32 num)245 static void pch_can_rw_msg_obj(void __iomem *creq_addr, u32 num)
246 {
247 	int counter = PCH_COUNTER_LIMIT;
248 	u32 ifx_creq;
249 
250 	iowrite32(num, creq_addr);
251 	while (counter) {
252 		ifx_creq = ioread32(creq_addr) & PCH_IF_CREQ_BUSY;
253 		if (!ifx_creq)
254 			break;
255 		counter--;
256 		udelay(1);
257 	}
258 	if (!counter)
259 		pr_err("%s:IF1 BUSY Flag is set forever.\n", __func__);
260 }
261 
pch_can_set_int_enables(struct pch_can_priv * priv,enum pch_can_mode interrupt_no)262 static void pch_can_set_int_enables(struct pch_can_priv *priv,
263 				    enum pch_can_mode interrupt_no)
264 {
265 	switch (interrupt_no) {
266 	case PCH_CAN_DISABLE:
267 		pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE);
268 		break;
269 
270 	case PCH_CAN_ALL:
271 		pch_can_bit_set(&priv->regs->cont, PCH_CTRL_IE_SIE_EIE);
272 		break;
273 
274 	case PCH_CAN_NONE:
275 		pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE_SIE_EIE);
276 		break;
277 
278 	default:
279 		netdev_err(priv->ndev, "Invalid interrupt number.\n");
280 		break;
281 	}
282 }
283 
pch_can_set_rxtx(struct pch_can_priv * priv,u32 buff_num,int set,enum pch_ifreg dir)284 static void pch_can_set_rxtx(struct pch_can_priv *priv, u32 buff_num,
285 			     int set, enum pch_ifreg dir)
286 {
287 	u32 ie;
288 
289 	if (dir)
290 		ie = PCH_IF_MCONT_TXIE;
291 	else
292 		ie = PCH_IF_MCONT_RXIE;
293 
294 	/* Reading the Msg buffer from Message RAM to IF1/2 registers. */
295 	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[dir].cmask);
296 	pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
297 
298 	/* Setting the IF1/2MASK1 register to access MsgVal and RxIE bits */
299 	iowrite32(PCH_CMASK_RDWR | PCH_CMASK_ARB | PCH_CMASK_CTRL,
300 		  &priv->regs->ifregs[dir].cmask);
301 
302 	if (set) {
303 		/* Setting the MsgVal and RxIE/TxIE bits */
304 		pch_can_bit_set(&priv->regs->ifregs[dir].mcont, ie);
305 		pch_can_bit_set(&priv->regs->ifregs[dir].id2, PCH_ID_MSGVAL);
306 	} else {
307 		/* Clearing the MsgVal and RxIE/TxIE bits */
308 		pch_can_bit_clear(&priv->regs->ifregs[dir].mcont, ie);
309 		pch_can_bit_clear(&priv->regs->ifregs[dir].id2, PCH_ID_MSGVAL);
310 	}
311 
312 	pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
313 }
314 
pch_can_set_rx_all(struct pch_can_priv * priv,int set)315 static void pch_can_set_rx_all(struct pch_can_priv *priv, int set)
316 {
317 	int i;
318 
319 	/* Traversing to obtain the object configured as receivers. */
320 	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++)
321 		pch_can_set_rxtx(priv, i, set, PCH_RX_IFREG);
322 }
323 
pch_can_set_tx_all(struct pch_can_priv * priv,int set)324 static void pch_can_set_tx_all(struct pch_can_priv *priv, int set)
325 {
326 	int i;
327 
328 	/* Traversing to obtain the object configured as transmit object. */
329 	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++)
330 		pch_can_set_rxtx(priv, i, set, PCH_TX_IFREG);
331 }
332 
pch_can_int_pending(struct pch_can_priv * priv)333 static u32 pch_can_int_pending(struct pch_can_priv *priv)
334 {
335 	return ioread32(&priv->regs->intr) & 0xffff;
336 }
337 
pch_can_clear_if_buffers(struct pch_can_priv * priv)338 static void pch_can_clear_if_buffers(struct pch_can_priv *priv)
339 {
340 	int i; /* Msg Obj ID (1~32) */
341 
342 	for (i = PCH_RX_OBJ_START; i <= PCH_TX_OBJ_END; i++) {
343 		iowrite32(PCH_CMASK_RX_TX_SET, &priv->regs->ifregs[0].cmask);
344 		iowrite32(0xffff, &priv->regs->ifregs[0].mask1);
345 		iowrite32(0xffff, &priv->regs->ifregs[0].mask2);
346 		iowrite32(0x0, &priv->regs->ifregs[0].id1);
347 		iowrite32(0x0, &priv->regs->ifregs[0].id2);
348 		iowrite32(0x0, &priv->regs->ifregs[0].mcont);
349 		iowrite32(0x0, &priv->regs->ifregs[0].data[0]);
350 		iowrite32(0x0, &priv->regs->ifregs[0].data[1]);
351 		iowrite32(0x0, &priv->regs->ifregs[0].data[2]);
352 		iowrite32(0x0, &priv->regs->ifregs[0].data[3]);
353 		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK |
354 			  PCH_CMASK_ARB | PCH_CMASK_CTRL,
355 			  &priv->regs->ifregs[0].cmask);
356 		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
357 	}
358 }
359 
pch_can_config_rx_tx_buffers(struct pch_can_priv * priv)360 static void pch_can_config_rx_tx_buffers(struct pch_can_priv *priv)
361 {
362 	int i;
363 
364 	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
365 		iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
366 		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
367 
368 		iowrite32(0x0, &priv->regs->ifregs[0].id1);
369 		iowrite32(0x0, &priv->regs->ifregs[0].id2);
370 
371 		pch_can_bit_set(&priv->regs->ifregs[0].mcont,
372 				PCH_IF_MCONT_UMASK);
373 
374 		/* In case FIFO mode, Last EoB of Rx Obj must be 1 */
375 		if (i == PCH_RX_OBJ_END)
376 			pch_can_bit_set(&priv->regs->ifregs[0].mcont,
377 					PCH_IF_MCONT_EOB);
378 		else
379 			pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
380 					  PCH_IF_MCONT_EOB);
381 
382 		iowrite32(0, &priv->regs->ifregs[0].mask1);
383 		pch_can_bit_clear(&priv->regs->ifregs[0].mask2,
384 				  0x1fff | PCH_MASK2_MDIR_MXTD);
385 
386 		/* Setting CMASK for writing */
387 		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK | PCH_CMASK_ARB |
388 			  PCH_CMASK_CTRL, &priv->regs->ifregs[0].cmask);
389 
390 		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
391 	}
392 
393 	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++) {
394 		iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[1].cmask);
395 		pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, i);
396 
397 		/* Resetting DIR bit for reception */
398 		iowrite32(0x0, &priv->regs->ifregs[1].id1);
399 		iowrite32(PCH_ID2_DIR, &priv->regs->ifregs[1].id2);
400 
401 		/* Setting EOB bit for transmitter */
402 		iowrite32(PCH_IF_MCONT_EOB | PCH_IF_MCONT_UMASK,
403 			  &priv->regs->ifregs[1].mcont);
404 
405 		iowrite32(0, &priv->regs->ifregs[1].mask1);
406 		pch_can_bit_clear(&priv->regs->ifregs[1].mask2, 0x1fff);
407 
408 		/* Setting CMASK for writing */
409 		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK | PCH_CMASK_ARB |
410 			  PCH_CMASK_CTRL, &priv->regs->ifregs[1].cmask);
411 
412 		pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, i);
413 	}
414 }
415 
pch_can_init(struct pch_can_priv * priv)416 static void pch_can_init(struct pch_can_priv *priv)
417 {
418 	/* Stopping the Can device. */
419 	pch_can_set_run_mode(priv, PCH_CAN_STOP);
420 
421 	/* Clearing all the message object buffers. */
422 	pch_can_clear_if_buffers(priv);
423 
424 	/* Configuring the respective message object as either rx/tx object. */
425 	pch_can_config_rx_tx_buffers(priv);
426 
427 	/* Enabling the interrupts. */
428 	pch_can_set_int_enables(priv, PCH_CAN_ALL);
429 }
430 
pch_can_release(struct pch_can_priv * priv)431 static void pch_can_release(struct pch_can_priv *priv)
432 {
433 	/* Stooping the CAN device. */
434 	pch_can_set_run_mode(priv, PCH_CAN_STOP);
435 
436 	/* Disabling the interrupts. */
437 	pch_can_set_int_enables(priv, PCH_CAN_NONE);
438 
439 	/* Disabling all the receive object. */
440 	pch_can_set_rx_all(priv, 0);
441 
442 	/* Disabling all the transmit object. */
443 	pch_can_set_tx_all(priv, 0);
444 }
445 
446 /* This function clears interrupt(s) from the CAN device. */
pch_can_int_clr(struct pch_can_priv * priv,u32 mask)447 static void pch_can_int_clr(struct pch_can_priv *priv, u32 mask)
448 {
449 	/* Clear interrupt for transmit object */
450 	if ((mask >= PCH_RX_OBJ_START) && (mask <= PCH_RX_OBJ_END)) {
451 		/* Setting CMASK for clearing the reception interrupts. */
452 		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL | PCH_CMASK_ARB,
453 			  &priv->regs->ifregs[0].cmask);
454 
455 		/* Clearing the Dir bit. */
456 		pch_can_bit_clear(&priv->regs->ifregs[0].id2, PCH_ID2_DIR);
457 
458 		/* Clearing NewDat & IntPnd */
459 		pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
460 				  PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_INTPND);
461 
462 		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, mask);
463 	} else if ((mask >= PCH_TX_OBJ_START) && (mask <= PCH_TX_OBJ_END)) {
464 		/*
465 		 * Setting CMASK for clearing interrupts for frame transmission.
466 		 */
467 		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL | PCH_CMASK_ARB,
468 			  &priv->regs->ifregs[1].cmask);
469 
470 		/* Resetting the ID registers. */
471 		pch_can_bit_set(&priv->regs->ifregs[1].id2,
472 			       PCH_ID2_DIR | (0x7ff << 2));
473 		iowrite32(0x0, &priv->regs->ifregs[1].id1);
474 
475 		/* Claring NewDat, TxRqst & IntPnd */
476 		pch_can_bit_clear(&priv->regs->ifregs[1].mcont,
477 				  PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_INTPND |
478 				  PCH_IF_MCONT_TXRQXT);
479 		pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, mask);
480 	}
481 }
482 
pch_can_reset(struct pch_can_priv * priv)483 static void pch_can_reset(struct pch_can_priv *priv)
484 {
485 	/* write to sw reset register */
486 	iowrite32(1, &priv->regs->srst);
487 	iowrite32(0, &priv->regs->srst);
488 }
489 
pch_can_error(struct net_device * ndev,u32 status)490 static void pch_can_error(struct net_device *ndev, u32 status)
491 {
492 	struct sk_buff *skb;
493 	struct pch_can_priv *priv = netdev_priv(ndev);
494 	struct can_frame *cf;
495 	u32 errc, lec;
496 	struct net_device_stats *stats = &(priv->ndev->stats);
497 	enum can_state state = priv->can.state;
498 
499 	skb = alloc_can_err_skb(ndev, &cf);
500 	if (!skb)
501 		return;
502 
503 	if (status & PCH_BUS_OFF) {
504 		pch_can_set_tx_all(priv, 0);
505 		pch_can_set_rx_all(priv, 0);
506 		state = CAN_STATE_BUS_OFF;
507 		cf->can_id |= CAN_ERR_BUSOFF;
508 		priv->can.can_stats.bus_off++;
509 		can_bus_off(ndev);
510 	}
511 
512 	errc = ioread32(&priv->regs->errc);
513 	/* Warning interrupt. */
514 	if (status & PCH_EWARN) {
515 		state = CAN_STATE_ERROR_WARNING;
516 		priv->can.can_stats.error_warning++;
517 		cf->can_id |= CAN_ERR_CRTL;
518 		if (((errc & PCH_REC) >> 8) > 96)
519 			cf->data[1] |= CAN_ERR_CRTL_RX_WARNING;
520 		if ((errc & PCH_TEC) > 96)
521 			cf->data[1] |= CAN_ERR_CRTL_TX_WARNING;
522 		netdev_dbg(ndev,
523 			"%s -> Error Counter is more than 96.\n", __func__);
524 	}
525 	/* Error passive interrupt. */
526 	if (status & PCH_EPASSIV) {
527 		priv->can.can_stats.error_passive++;
528 		state = CAN_STATE_ERROR_PASSIVE;
529 		cf->can_id |= CAN_ERR_CRTL;
530 		if (errc & PCH_RP)
531 			cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
532 		if ((errc & PCH_TEC) > 127)
533 			cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
534 		netdev_dbg(ndev,
535 			"%s -> CAN controller is ERROR PASSIVE .\n", __func__);
536 	}
537 
538 	lec = status & PCH_LEC_ALL;
539 	switch (lec) {
540 	case PCH_STUF_ERR:
541 		cf->data[2] |= CAN_ERR_PROT_STUFF;
542 		priv->can.can_stats.bus_error++;
543 		stats->rx_errors++;
544 		break;
545 	case PCH_FORM_ERR:
546 		cf->data[2] |= CAN_ERR_PROT_FORM;
547 		priv->can.can_stats.bus_error++;
548 		stats->rx_errors++;
549 		break;
550 	case PCH_ACK_ERR:
551 		cf->can_id |= CAN_ERR_ACK;
552 		priv->can.can_stats.bus_error++;
553 		stats->rx_errors++;
554 		break;
555 	case PCH_BIT1_ERR:
556 	case PCH_BIT0_ERR:
557 		cf->data[2] |= CAN_ERR_PROT_BIT;
558 		priv->can.can_stats.bus_error++;
559 		stats->rx_errors++;
560 		break;
561 	case PCH_CRC_ERR:
562 		cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
563 		priv->can.can_stats.bus_error++;
564 		stats->rx_errors++;
565 		break;
566 	case PCH_LEC_ALL: /* Written by CPU. No error status */
567 		break;
568 	}
569 
570 	cf->data[6] = errc & PCH_TEC;
571 	cf->data[7] = (errc & PCH_REC) >> 8;
572 
573 	priv->can.state = state;
574 	netif_receive_skb(skb);
575 
576 	stats->rx_packets++;
577 	stats->rx_bytes += cf->can_dlc;
578 }
579 
pch_can_interrupt(int irq,void * dev_id)580 static irqreturn_t pch_can_interrupt(int irq, void *dev_id)
581 {
582 	struct net_device *ndev = (struct net_device *)dev_id;
583 	struct pch_can_priv *priv = netdev_priv(ndev);
584 
585 	if (!pch_can_int_pending(priv))
586 		return IRQ_NONE;
587 
588 	pch_can_set_int_enables(priv, PCH_CAN_NONE);
589 	napi_schedule(&priv->napi);
590 	return IRQ_HANDLED;
591 }
592 
pch_fifo_thresh(struct pch_can_priv * priv,int obj_id)593 static void pch_fifo_thresh(struct pch_can_priv *priv, int obj_id)
594 {
595 	if (obj_id < PCH_FIFO_THRESH) {
596 		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL |
597 			  PCH_CMASK_ARB, &priv->regs->ifregs[0].cmask);
598 
599 		/* Clearing the Dir bit. */
600 		pch_can_bit_clear(&priv->regs->ifregs[0].id2, PCH_ID2_DIR);
601 
602 		/* Clearing NewDat & IntPnd */
603 		pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
604 				  PCH_IF_MCONT_INTPND);
605 		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_id);
606 	} else if (obj_id > PCH_FIFO_THRESH) {
607 		pch_can_int_clr(priv, obj_id);
608 	} else if (obj_id == PCH_FIFO_THRESH) {
609 		int cnt;
610 		for (cnt = 0; cnt < PCH_FIFO_THRESH; cnt++)
611 			pch_can_int_clr(priv, cnt + 1);
612 	}
613 }
614 
pch_can_rx_msg_lost(struct net_device * ndev,int obj_id)615 static void pch_can_rx_msg_lost(struct net_device *ndev, int obj_id)
616 {
617 	struct pch_can_priv *priv = netdev_priv(ndev);
618 	struct net_device_stats *stats = &(priv->ndev->stats);
619 	struct sk_buff *skb;
620 	struct can_frame *cf;
621 
622 	netdev_dbg(priv->ndev, "Msg Obj is overwritten.\n");
623 	pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
624 			  PCH_IF_MCONT_MSGLOST);
625 	iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL,
626 		  &priv->regs->ifregs[0].cmask);
627 	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_id);
628 
629 	skb = alloc_can_err_skb(ndev, &cf);
630 	if (!skb)
631 		return;
632 
633 	cf->can_id |= CAN_ERR_CRTL;
634 	cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
635 	stats->rx_over_errors++;
636 	stats->rx_errors++;
637 
638 	netif_receive_skb(skb);
639 }
640 
pch_can_rx_normal(struct net_device * ndev,u32 obj_num,int quota)641 static int pch_can_rx_normal(struct net_device *ndev, u32 obj_num, int quota)
642 {
643 	u32 reg;
644 	canid_t id;
645 	int rcv_pkts = 0;
646 	struct sk_buff *skb;
647 	struct can_frame *cf;
648 	struct pch_can_priv *priv = netdev_priv(ndev);
649 	struct net_device_stats *stats = &(priv->ndev->stats);
650 	int i;
651 	u32 id2;
652 	u16 data_reg;
653 
654 	do {
655 		/* Reading the message object from the Message RAM */
656 		iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
657 		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_num);
658 
659 		/* Reading the MCONT register. */
660 		reg = ioread32(&priv->regs->ifregs[0].mcont);
661 
662 		if (reg & PCH_IF_MCONT_EOB)
663 			break;
664 
665 		/* If MsgLost bit set. */
666 		if (reg & PCH_IF_MCONT_MSGLOST) {
667 			pch_can_rx_msg_lost(ndev, obj_num);
668 			rcv_pkts++;
669 			quota--;
670 			obj_num++;
671 			continue;
672 		} else if (!(reg & PCH_IF_MCONT_NEWDAT)) {
673 			obj_num++;
674 			continue;
675 		}
676 
677 		skb = alloc_can_skb(priv->ndev, &cf);
678 		if (!skb) {
679 			netdev_err(ndev, "alloc_can_skb Failed\n");
680 			return rcv_pkts;
681 		}
682 
683 		/* Get Received data */
684 		id2 = ioread32(&priv->regs->ifregs[0].id2);
685 		if (id2 & PCH_ID2_XTD) {
686 			id = (ioread32(&priv->regs->ifregs[0].id1) & 0xffff);
687 			id |= (((id2) & 0x1fff) << 16);
688 			cf->can_id = id | CAN_EFF_FLAG;
689 		} else {
690 			id = (id2 >> 2) & CAN_SFF_MASK;
691 			cf->can_id = id;
692 		}
693 
694 		if (id2 & PCH_ID2_DIR)
695 			cf->can_id |= CAN_RTR_FLAG;
696 
697 		cf->can_dlc = get_can_dlc((ioread32(&priv->regs->
698 						    ifregs[0].mcont)) & 0xF);
699 
700 		for (i = 0; i < cf->can_dlc; i += 2) {
701 			data_reg = ioread16(&priv->regs->ifregs[0].data[i / 2]);
702 			cf->data[i] = data_reg;
703 			cf->data[i + 1] = data_reg >> 8;
704 		}
705 
706 		netif_receive_skb(skb);
707 		rcv_pkts++;
708 		stats->rx_packets++;
709 		quota--;
710 		stats->rx_bytes += cf->can_dlc;
711 
712 		pch_fifo_thresh(priv, obj_num);
713 		obj_num++;
714 	} while (quota > 0);
715 
716 	return rcv_pkts;
717 }
718 
pch_can_tx_complete(struct net_device * ndev,u32 int_stat)719 static void pch_can_tx_complete(struct net_device *ndev, u32 int_stat)
720 {
721 	struct pch_can_priv *priv = netdev_priv(ndev);
722 	struct net_device_stats *stats = &(priv->ndev->stats);
723 	u32 dlc;
724 
725 	can_get_echo_skb(ndev, int_stat - PCH_RX_OBJ_END - 1);
726 	iowrite32(PCH_CMASK_RX_TX_GET | PCH_CMASK_CLRINTPND,
727 		  &priv->regs->ifregs[1].cmask);
728 	pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, int_stat);
729 	dlc = get_can_dlc(ioread32(&priv->regs->ifregs[1].mcont) &
730 			  PCH_IF_MCONT_DLC);
731 	stats->tx_bytes += dlc;
732 	stats->tx_packets++;
733 	if (int_stat == PCH_TX_OBJ_END)
734 		netif_wake_queue(ndev);
735 }
736 
pch_can_poll(struct napi_struct * napi,int quota)737 static int pch_can_poll(struct napi_struct *napi, int quota)
738 {
739 	struct net_device *ndev = napi->dev;
740 	struct pch_can_priv *priv = netdev_priv(ndev);
741 	u32 int_stat;
742 	u32 reg_stat;
743 	int quota_save = quota;
744 
745 	int_stat = pch_can_int_pending(priv);
746 	if (!int_stat)
747 		goto end;
748 
749 	if (int_stat == PCH_STATUS_INT) {
750 		reg_stat = ioread32(&priv->regs->stat);
751 
752 		if ((reg_stat & (PCH_BUS_OFF | PCH_LEC_ALL)) &&
753 		   ((reg_stat & PCH_LEC_ALL) != PCH_LEC_ALL)) {
754 			pch_can_error(ndev, reg_stat);
755 			quota--;
756 		}
757 
758 		if (reg_stat & (PCH_TX_OK | PCH_RX_OK))
759 			pch_can_bit_clear(&priv->regs->stat,
760 					  reg_stat & (PCH_TX_OK | PCH_RX_OK));
761 
762 		int_stat = pch_can_int_pending(priv);
763 	}
764 
765 	if (quota == 0)
766 		goto end;
767 
768 	if ((int_stat >= PCH_RX_OBJ_START) && (int_stat <= PCH_RX_OBJ_END)) {
769 		quota -= pch_can_rx_normal(ndev, int_stat, quota);
770 	} else if ((int_stat >= PCH_TX_OBJ_START) &&
771 		   (int_stat <= PCH_TX_OBJ_END)) {
772 		/* Handle transmission interrupt */
773 		pch_can_tx_complete(ndev, int_stat);
774 	}
775 
776 end:
777 	napi_complete(napi);
778 	pch_can_set_int_enables(priv, PCH_CAN_ALL);
779 
780 	return quota_save - quota;
781 }
782 
pch_set_bittiming(struct net_device * ndev)783 static int pch_set_bittiming(struct net_device *ndev)
784 {
785 	struct pch_can_priv *priv = netdev_priv(ndev);
786 	const struct can_bittiming *bt = &priv->can.bittiming;
787 	u32 canbit;
788 	u32 bepe;
789 
790 	/* Setting the CCE bit for accessing the Can Timing register. */
791 	pch_can_bit_set(&priv->regs->cont, PCH_CTRL_CCE);
792 
793 	canbit = (bt->brp - 1) & PCH_MSK_BITT_BRP;
794 	canbit |= (bt->sjw - 1) << PCH_BIT_SJW_SHIFT;
795 	canbit |= (bt->phase_seg1 + bt->prop_seg - 1) << PCH_BIT_TSEG1_SHIFT;
796 	canbit |= (bt->phase_seg2 - 1) << PCH_BIT_TSEG2_SHIFT;
797 	bepe = ((bt->brp - 1) & PCH_MSK_BRPE_BRPE) >> PCH_BIT_BRPE_BRPE_SHIFT;
798 	iowrite32(canbit, &priv->regs->bitt);
799 	iowrite32(bepe, &priv->regs->brpe);
800 	pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_CCE);
801 
802 	return 0;
803 }
804 
pch_can_start(struct net_device * ndev)805 static void pch_can_start(struct net_device *ndev)
806 {
807 	struct pch_can_priv *priv = netdev_priv(ndev);
808 
809 	if (priv->can.state != CAN_STATE_STOPPED)
810 		pch_can_reset(priv);
811 
812 	pch_set_bittiming(ndev);
813 	pch_can_set_optmode(priv);
814 
815 	pch_can_set_tx_all(priv, 1);
816 	pch_can_set_rx_all(priv, 1);
817 
818 	/* Setting the CAN to run mode. */
819 	pch_can_set_run_mode(priv, PCH_CAN_RUN);
820 
821 	priv->can.state = CAN_STATE_ERROR_ACTIVE;
822 
823 	return;
824 }
825 
pch_can_do_set_mode(struct net_device * ndev,enum can_mode mode)826 static int pch_can_do_set_mode(struct net_device *ndev, enum can_mode mode)
827 {
828 	int ret = 0;
829 
830 	switch (mode) {
831 	case CAN_MODE_START:
832 		pch_can_start(ndev);
833 		netif_wake_queue(ndev);
834 		break;
835 	default:
836 		ret = -EOPNOTSUPP;
837 		break;
838 	}
839 
840 	return ret;
841 }
842 
pch_can_open(struct net_device * ndev)843 static int pch_can_open(struct net_device *ndev)
844 {
845 	struct pch_can_priv *priv = netdev_priv(ndev);
846 	int retval;
847 
848 	/* Regstering the interrupt. */
849 	retval = request_irq(priv->dev->irq, pch_can_interrupt, IRQF_SHARED,
850 			     ndev->name, ndev);
851 	if (retval) {
852 		netdev_err(ndev, "request_irq failed.\n");
853 		goto req_irq_err;
854 	}
855 
856 	/* Open common can device */
857 	retval = open_candev(ndev);
858 	if (retval) {
859 		netdev_err(ndev, "open_candev() failed %d\n", retval);
860 		goto err_open_candev;
861 	}
862 
863 	pch_can_init(priv);
864 	pch_can_start(ndev);
865 	napi_enable(&priv->napi);
866 	netif_start_queue(ndev);
867 
868 	return 0;
869 
870 err_open_candev:
871 	free_irq(priv->dev->irq, ndev);
872 req_irq_err:
873 	pch_can_release(priv);
874 
875 	return retval;
876 }
877 
pch_close(struct net_device * ndev)878 static int pch_close(struct net_device *ndev)
879 {
880 	struct pch_can_priv *priv = netdev_priv(ndev);
881 
882 	netif_stop_queue(ndev);
883 	napi_disable(&priv->napi);
884 	pch_can_release(priv);
885 	free_irq(priv->dev->irq, ndev);
886 	close_candev(ndev);
887 	priv->can.state = CAN_STATE_STOPPED;
888 	return 0;
889 }
890 
pch_xmit(struct sk_buff * skb,struct net_device * ndev)891 static netdev_tx_t pch_xmit(struct sk_buff *skb, struct net_device *ndev)
892 {
893 	struct pch_can_priv *priv = netdev_priv(ndev);
894 	struct can_frame *cf = (struct can_frame *)skb->data;
895 	int tx_obj_no;
896 	int i;
897 	u32 id2;
898 
899 	if (can_dropped_invalid_skb(ndev, skb))
900 		return NETDEV_TX_OK;
901 
902 	tx_obj_no = priv->tx_obj;
903 	if (priv->tx_obj == PCH_TX_OBJ_END) {
904 		if (ioread32(&priv->regs->treq2) & PCH_TREQ2_TX_MASK)
905 			netif_stop_queue(ndev);
906 
907 		priv->tx_obj = PCH_TX_OBJ_START;
908 	} else {
909 		priv->tx_obj++;
910 	}
911 
912 	/* Setting the CMASK register. */
913 	pch_can_bit_set(&priv->regs->ifregs[1].cmask, PCH_CMASK_ALL);
914 
915 	/* If ID extended is set. */
916 	if (cf->can_id & CAN_EFF_FLAG) {
917 		iowrite32(cf->can_id & 0xffff, &priv->regs->ifregs[1].id1);
918 		id2 = ((cf->can_id >> 16) & 0x1fff) | PCH_ID2_XTD;
919 	} else {
920 		iowrite32(0, &priv->regs->ifregs[1].id1);
921 		id2 = (cf->can_id & CAN_SFF_MASK) << 2;
922 	}
923 
924 	id2 |= PCH_ID_MSGVAL;
925 
926 	/* If remote frame has to be transmitted.. */
927 	if (!(cf->can_id & CAN_RTR_FLAG))
928 		id2 |= PCH_ID2_DIR;
929 
930 	iowrite32(id2, &priv->regs->ifregs[1].id2);
931 
932 	/* Copy data to register */
933 	for (i = 0; i < cf->can_dlc; i += 2) {
934 		iowrite16(cf->data[i] | (cf->data[i + 1] << 8),
935 			  &priv->regs->ifregs[1].data[i / 2]);
936 	}
937 
938 	can_put_echo_skb(skb, ndev, tx_obj_no - PCH_RX_OBJ_END - 1);
939 
940 	/* Set the size of the data. Update if2_mcont */
941 	iowrite32(cf->can_dlc | PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_TXRQXT |
942 		  PCH_IF_MCONT_TXIE, &priv->regs->ifregs[1].mcont);
943 
944 	pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, tx_obj_no);
945 
946 	return NETDEV_TX_OK;
947 }
948 
949 static const struct net_device_ops pch_can_netdev_ops = {
950 	.ndo_open		= pch_can_open,
951 	.ndo_stop		= pch_close,
952 	.ndo_start_xmit		= pch_xmit,
953 	.ndo_change_mtu		= can_change_mtu,
954 };
955 
pch_can_remove(struct pci_dev * pdev)956 static void pch_can_remove(struct pci_dev *pdev)
957 {
958 	struct net_device *ndev = pci_get_drvdata(pdev);
959 	struct pch_can_priv *priv = netdev_priv(ndev);
960 
961 	unregister_candev(priv->ndev);
962 	if (priv->use_msi)
963 		pci_disable_msi(priv->dev);
964 	pci_release_regions(pdev);
965 	pci_disable_device(pdev);
966 	pch_can_reset(priv);
967 	pci_iounmap(pdev, priv->regs);
968 	free_candev(priv->ndev);
969 }
970 
971 #ifdef CONFIG_PM
pch_can_set_int_custom(struct pch_can_priv * priv)972 static void pch_can_set_int_custom(struct pch_can_priv *priv)
973 {
974 	/* Clearing the IE, SIE and EIE bits of Can control register. */
975 	pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE_SIE_EIE);
976 
977 	/* Appropriately setting them. */
978 	pch_can_bit_set(&priv->regs->cont,
979 			((priv->int_enables & PCH_MSK_CTRL_IE_SIE_EIE) << 1));
980 }
981 
982 /* This function retrieves interrupt enabled for the CAN device. */
pch_can_get_int_enables(struct pch_can_priv * priv)983 static u32 pch_can_get_int_enables(struct pch_can_priv *priv)
984 {
985 	/* Obtaining the status of IE, SIE and EIE interrupt bits. */
986 	return (ioread32(&priv->regs->cont) & PCH_CTRL_IE_SIE_EIE) >> 1;
987 }
988 
pch_can_get_rxtx_ir(struct pch_can_priv * priv,u32 buff_num,enum pch_ifreg dir)989 static u32 pch_can_get_rxtx_ir(struct pch_can_priv *priv, u32 buff_num,
990 			       enum pch_ifreg dir)
991 {
992 	u32 ie, enable;
993 
994 	if (dir)
995 		ie = PCH_IF_MCONT_RXIE;
996 	else
997 		ie = PCH_IF_MCONT_TXIE;
998 
999 	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[dir].cmask);
1000 	pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
1001 
1002 	if (((ioread32(&priv->regs->ifregs[dir].id2)) & PCH_ID_MSGVAL) &&
1003 			((ioread32(&priv->regs->ifregs[dir].mcont)) & ie))
1004 		enable = 1;
1005 	else
1006 		enable = 0;
1007 
1008 	return enable;
1009 }
1010 
pch_can_set_rx_buffer_link(struct pch_can_priv * priv,u32 buffer_num,int set)1011 static void pch_can_set_rx_buffer_link(struct pch_can_priv *priv,
1012 				       u32 buffer_num, int set)
1013 {
1014 	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
1015 	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
1016 	iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL,
1017 		  &priv->regs->ifregs[0].cmask);
1018 	if (set)
1019 		pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
1020 				  PCH_IF_MCONT_EOB);
1021 	else
1022 		pch_can_bit_set(&priv->regs->ifregs[0].mcont, PCH_IF_MCONT_EOB);
1023 
1024 	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
1025 }
1026 
pch_can_get_rx_buffer_link(struct pch_can_priv * priv,u32 buffer_num)1027 static u32 pch_can_get_rx_buffer_link(struct pch_can_priv *priv, u32 buffer_num)
1028 {
1029 	u32 link;
1030 
1031 	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
1032 	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
1033 
1034 	if (ioread32(&priv->regs->ifregs[0].mcont) & PCH_IF_MCONT_EOB)
1035 		link = 0;
1036 	else
1037 		link = 1;
1038 	return link;
1039 }
1040 
pch_can_get_buffer_status(struct pch_can_priv * priv)1041 static int pch_can_get_buffer_status(struct pch_can_priv *priv)
1042 {
1043 	return (ioread32(&priv->regs->treq1) & 0xffff) |
1044 	       (ioread32(&priv->regs->treq2) << 16);
1045 }
1046 
pch_can_suspend(struct pci_dev * pdev,pm_message_t state)1047 static int pch_can_suspend(struct pci_dev *pdev, pm_message_t state)
1048 {
1049 	int i;
1050 	int retval;
1051 	u32 buf_stat;	/* Variable for reading the transmit buffer status. */
1052 	int counter = PCH_COUNTER_LIMIT;
1053 
1054 	struct net_device *dev = pci_get_drvdata(pdev);
1055 	struct pch_can_priv *priv = netdev_priv(dev);
1056 
1057 	/* Stop the CAN controller */
1058 	pch_can_set_run_mode(priv, PCH_CAN_STOP);
1059 
1060 	/* Indicate that we are aboutto/in suspend */
1061 	priv->can.state = CAN_STATE_STOPPED;
1062 
1063 	/* Waiting for all transmission to complete. */
1064 	while (counter) {
1065 		buf_stat = pch_can_get_buffer_status(priv);
1066 		if (!buf_stat)
1067 			break;
1068 		counter--;
1069 		udelay(1);
1070 	}
1071 	if (!counter)
1072 		dev_err(&pdev->dev, "%s -> Transmission time out.\n", __func__);
1073 
1074 	/* Save interrupt configuration and then disable them */
1075 	priv->int_enables = pch_can_get_int_enables(priv);
1076 	pch_can_set_int_enables(priv, PCH_CAN_DISABLE);
1077 
1078 	/* Save Tx buffer enable state */
1079 	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++)
1080 		priv->tx_enable[i - 1] = pch_can_get_rxtx_ir(priv, i,
1081 							     PCH_TX_IFREG);
1082 
1083 	/* Disable all Transmit buffers */
1084 	pch_can_set_tx_all(priv, 0);
1085 
1086 	/* Save Rx buffer enable state */
1087 	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
1088 		priv->rx_enable[i - 1] = pch_can_get_rxtx_ir(priv, i,
1089 							     PCH_RX_IFREG);
1090 		priv->rx_link[i - 1] = pch_can_get_rx_buffer_link(priv, i);
1091 	}
1092 
1093 	/* Disable all Receive buffers */
1094 	pch_can_set_rx_all(priv, 0);
1095 	retval = pci_save_state(pdev);
1096 	if (retval) {
1097 		dev_err(&pdev->dev, "pci_save_state failed.\n");
1098 	} else {
1099 		pci_enable_wake(pdev, PCI_D3hot, 0);
1100 		pci_disable_device(pdev);
1101 		pci_set_power_state(pdev, pci_choose_state(pdev, state));
1102 	}
1103 
1104 	return retval;
1105 }
1106 
pch_can_resume(struct pci_dev * pdev)1107 static int pch_can_resume(struct pci_dev *pdev)
1108 {
1109 	int i;
1110 	int retval;
1111 	struct net_device *dev = pci_get_drvdata(pdev);
1112 	struct pch_can_priv *priv = netdev_priv(dev);
1113 
1114 	pci_set_power_state(pdev, PCI_D0);
1115 	pci_restore_state(pdev);
1116 	retval = pci_enable_device(pdev);
1117 	if (retval) {
1118 		dev_err(&pdev->dev, "pci_enable_device failed.\n");
1119 		return retval;
1120 	}
1121 
1122 	pci_enable_wake(pdev, PCI_D3hot, 0);
1123 
1124 	priv->can.state = CAN_STATE_ERROR_ACTIVE;
1125 
1126 	/* Disabling all interrupts. */
1127 	pch_can_set_int_enables(priv, PCH_CAN_DISABLE);
1128 
1129 	/* Setting the CAN device in Stop Mode. */
1130 	pch_can_set_run_mode(priv, PCH_CAN_STOP);
1131 
1132 	/* Configuring the transmit and receive buffers. */
1133 	pch_can_config_rx_tx_buffers(priv);
1134 
1135 	/* Restore the CAN state */
1136 	pch_set_bittiming(dev);
1137 
1138 	/* Listen/Active */
1139 	pch_can_set_optmode(priv);
1140 
1141 	/* Enabling the transmit buffer. */
1142 	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++)
1143 		pch_can_set_rxtx(priv, i, priv->tx_enable[i - 1], PCH_TX_IFREG);
1144 
1145 	/* Configuring the receive buffer and enabling them. */
1146 	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
1147 		/* Restore buffer link */
1148 		pch_can_set_rx_buffer_link(priv, i, priv->rx_link[i - 1]);
1149 
1150 		/* Restore buffer enables */
1151 		pch_can_set_rxtx(priv, i, priv->rx_enable[i - 1], PCH_RX_IFREG);
1152 	}
1153 
1154 	/* Enable CAN Interrupts */
1155 	pch_can_set_int_custom(priv);
1156 
1157 	/* Restore Run Mode */
1158 	pch_can_set_run_mode(priv, PCH_CAN_RUN);
1159 
1160 	return retval;
1161 }
1162 #else
1163 #define pch_can_suspend NULL
1164 #define pch_can_resume NULL
1165 #endif
1166 
pch_can_get_berr_counter(const struct net_device * dev,struct can_berr_counter * bec)1167 static int pch_can_get_berr_counter(const struct net_device *dev,
1168 				    struct can_berr_counter *bec)
1169 {
1170 	struct pch_can_priv *priv = netdev_priv(dev);
1171 	u32 errc = ioread32(&priv->regs->errc);
1172 
1173 	bec->txerr = errc & PCH_TEC;
1174 	bec->rxerr = (errc & PCH_REC) >> 8;
1175 
1176 	return 0;
1177 }
1178 
pch_can_probe(struct pci_dev * pdev,const struct pci_device_id * id)1179 static int pch_can_probe(struct pci_dev *pdev,
1180 				   const struct pci_device_id *id)
1181 {
1182 	struct net_device *ndev;
1183 	struct pch_can_priv *priv;
1184 	int rc;
1185 	void __iomem *addr;
1186 
1187 	rc = pci_enable_device(pdev);
1188 	if (rc) {
1189 		dev_err(&pdev->dev, "Failed pci_enable_device %d\n", rc);
1190 		goto probe_exit_endev;
1191 	}
1192 
1193 	rc = pci_request_regions(pdev, KBUILD_MODNAME);
1194 	if (rc) {
1195 		dev_err(&pdev->dev, "Failed pci_request_regions %d\n", rc);
1196 		goto probe_exit_pcireq;
1197 	}
1198 
1199 	addr = pci_iomap(pdev, 1, 0);
1200 	if (!addr) {
1201 		rc = -EIO;
1202 		dev_err(&pdev->dev, "Failed pci_iomap\n");
1203 		goto probe_exit_ipmap;
1204 	}
1205 
1206 	ndev = alloc_candev(sizeof(struct pch_can_priv), PCH_TX_OBJ_END);
1207 	if (!ndev) {
1208 		rc = -ENOMEM;
1209 		dev_err(&pdev->dev, "Failed alloc_candev\n");
1210 		goto probe_exit_alloc_candev;
1211 	}
1212 
1213 	priv = netdev_priv(ndev);
1214 	priv->ndev = ndev;
1215 	priv->regs = addr;
1216 	priv->dev = pdev;
1217 	priv->can.bittiming_const = &pch_can_bittiming_const;
1218 	priv->can.do_set_mode = pch_can_do_set_mode;
1219 	priv->can.do_get_berr_counter = pch_can_get_berr_counter;
1220 	priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY |
1221 				       CAN_CTRLMODE_LOOPBACK;
1222 	priv->tx_obj = PCH_TX_OBJ_START; /* Point head of Tx Obj */
1223 
1224 	ndev->irq = pdev->irq;
1225 	ndev->flags |= IFF_ECHO;
1226 
1227 	pci_set_drvdata(pdev, ndev);
1228 	SET_NETDEV_DEV(ndev, &pdev->dev);
1229 	ndev->netdev_ops = &pch_can_netdev_ops;
1230 	priv->can.clock.freq = PCH_CAN_CLK; /* Hz */
1231 
1232 	netif_napi_add(ndev, &priv->napi, pch_can_poll, PCH_RX_OBJ_END);
1233 
1234 	rc = pci_enable_msi(priv->dev);
1235 	if (rc) {
1236 		netdev_err(ndev, "PCH CAN opened without MSI\n");
1237 		priv->use_msi = 0;
1238 	} else {
1239 		netdev_err(ndev, "PCH CAN opened with MSI\n");
1240 		pci_set_master(pdev);
1241 		priv->use_msi = 1;
1242 	}
1243 
1244 	rc = register_candev(ndev);
1245 	if (rc) {
1246 		dev_err(&pdev->dev, "Failed register_candev %d\n", rc);
1247 		goto probe_exit_reg_candev;
1248 	}
1249 
1250 	return 0;
1251 
1252 probe_exit_reg_candev:
1253 	if (priv->use_msi)
1254 		pci_disable_msi(priv->dev);
1255 	free_candev(ndev);
1256 probe_exit_alloc_candev:
1257 	pci_iounmap(pdev, addr);
1258 probe_exit_ipmap:
1259 	pci_release_regions(pdev);
1260 probe_exit_pcireq:
1261 	pci_disable_device(pdev);
1262 probe_exit_endev:
1263 	return rc;
1264 }
1265 
1266 static struct pci_driver pch_can_pci_driver = {
1267 	.name = "pch_can",
1268 	.id_table = pch_pci_tbl,
1269 	.probe = pch_can_probe,
1270 	.remove = pch_can_remove,
1271 	.suspend = pch_can_suspend,
1272 	.resume = pch_can_resume,
1273 };
1274 
1275 module_pci_driver(pch_can_pci_driver);
1276 
1277 MODULE_DESCRIPTION("Intel EG20T PCH CAN(Controller Area Network) Driver");
1278 MODULE_LICENSE("GPL v2");
1279 MODULE_VERSION("0.94");
1280