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, write to the Free Software
16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
17  */
18 
19 #include <linux/interrupt.h>
20 #include <linux/delay.h>
21 #include <linux/io.h>
22 #include <linux/module.h>
23 #include <linux/sched.h>
24 #include <linux/pci.h>
25 #include <linux/init.h>
26 #include <linux/kernel.h>
27 #include <linux/types.h>
28 #include <linux/errno.h>
29 #include <linux/netdevice.h>
30 #include <linux/skbuff.h>
31 #include <linux/can.h>
32 #include <linux/can/dev.h>
33 #include <linux/can/error.h>
34 
35 #define PCH_CTRL_INIT		BIT(0) /* The INIT bit of CANCONT register. */
36 #define PCH_CTRL_IE		BIT(1) /* The IE bit of CAN control register */
37 #define PCH_CTRL_IE_SIE_EIE	(BIT(3) | BIT(2) | BIT(1))
38 #define PCH_CTRL_CCE		BIT(6)
39 #define PCH_CTRL_OPT		BIT(7) /* The OPT bit of CANCONT register. */
40 #define PCH_OPT_SILENT		BIT(3) /* The Silent bit of CANOPT reg. */
41 #define PCH_OPT_LBACK		BIT(4) /* The LoopBack bit of CANOPT reg. */
42 
43 #define PCH_CMASK_RX_TX_SET	0x00f3
44 #define PCH_CMASK_RX_TX_GET	0x0073
45 #define PCH_CMASK_ALL		0xff
46 #define PCH_CMASK_NEWDAT	BIT(2)
47 #define PCH_CMASK_CLRINTPND	BIT(3)
48 #define PCH_CMASK_CTRL		BIT(4)
49 #define PCH_CMASK_ARB		BIT(5)
50 #define PCH_CMASK_MASK		BIT(6)
51 #define PCH_CMASK_RDWR		BIT(7)
52 #define PCH_IF_MCONT_NEWDAT	BIT(15)
53 #define PCH_IF_MCONT_MSGLOST	BIT(14)
54 #define PCH_IF_MCONT_INTPND	BIT(13)
55 #define PCH_IF_MCONT_UMASK	BIT(12)
56 #define PCH_IF_MCONT_TXIE	BIT(11)
57 #define PCH_IF_MCONT_RXIE	BIT(10)
58 #define PCH_IF_MCONT_RMTEN	BIT(9)
59 #define PCH_IF_MCONT_TXRQXT	BIT(8)
60 #define PCH_IF_MCONT_EOB	BIT(7)
61 #define PCH_IF_MCONT_DLC	(BIT(0) | BIT(1) | BIT(2) | BIT(3))
62 #define PCH_MASK2_MDIR_MXTD	(BIT(14) | BIT(15))
63 #define PCH_ID2_DIR		BIT(13)
64 #define PCH_ID2_XTD		BIT(14)
65 #define PCH_ID_MSGVAL		BIT(15)
66 #define PCH_IF_CREQ_BUSY	BIT(15)
67 
68 #define PCH_STATUS_INT		0x8000
69 #define PCH_RP			0x00008000
70 #define PCH_REC			0x00007f00
71 #define PCH_TEC			0x000000ff
72 
73 #define PCH_TX_OK		BIT(3)
74 #define PCH_RX_OK		BIT(4)
75 #define PCH_EPASSIV		BIT(5)
76 #define PCH_EWARN		BIT(6)
77 #define PCH_BUS_OFF		BIT(7)
78 
79 /* bit position of certain controller bits. */
80 #define PCH_BIT_BRP_SHIFT	0
81 #define PCH_BIT_SJW_SHIFT	6
82 #define PCH_BIT_TSEG1_SHIFT	8
83 #define PCH_BIT_TSEG2_SHIFT	12
84 #define PCH_BIT_BRPE_BRPE_SHIFT	6
85 
86 #define PCH_MSK_BITT_BRP	0x3f
87 #define PCH_MSK_BRPE_BRPE	0x3c0
88 #define PCH_MSK_CTRL_IE_SIE_EIE	0x07
89 #define PCH_COUNTER_LIMIT	10
90 
91 #define PCH_CAN_CLK		50000000	/* 50MHz */
92 
93 /*
94  * Define the number of message object.
95  * PCH CAN communications are done via Message RAM.
96  * The Message RAM consists of 32 message objects.
97  */
98 #define PCH_RX_OBJ_NUM		26
99 #define PCH_TX_OBJ_NUM		6
100 #define PCH_RX_OBJ_START	1
101 #define PCH_RX_OBJ_END		PCH_RX_OBJ_NUM
102 #define PCH_TX_OBJ_START	(PCH_RX_OBJ_END + 1)
103 #define PCH_TX_OBJ_END		(PCH_RX_OBJ_NUM + PCH_TX_OBJ_NUM)
104 
105 #define PCH_FIFO_THRESH		16
106 
107 /* TxRqst2 show status of MsgObjNo.17~32 */
108 #define PCH_TREQ2_TX_MASK	(((1 << PCH_TX_OBJ_NUM) - 1) <<\
109 							(PCH_RX_OBJ_END - 16))
110 
111 enum pch_ifreg {
112 	PCH_RX_IFREG,
113 	PCH_TX_IFREG,
114 };
115 
116 enum pch_can_err {
117 	PCH_STUF_ERR = 1,
118 	PCH_FORM_ERR,
119 	PCH_ACK_ERR,
120 	PCH_BIT1_ERR,
121 	PCH_BIT0_ERR,
122 	PCH_CRC_ERR,
123 	PCH_LEC_ALL,
124 };
125 
126 enum pch_can_mode {
127 	PCH_CAN_ENABLE,
128 	PCH_CAN_DISABLE,
129 	PCH_CAN_ALL,
130 	PCH_CAN_NONE,
131 	PCH_CAN_STOP,
132 	PCH_CAN_RUN,
133 };
134 
135 struct pch_can_if_regs {
136 	u32 creq;
137 	u32 cmask;
138 	u32 mask1;
139 	u32 mask2;
140 	u32 id1;
141 	u32 id2;
142 	u32 mcont;
143 	u32 data[4];
144 	u32 rsv[13];
145 };
146 
147 struct pch_can_regs {
148 	u32 cont;
149 	u32 stat;
150 	u32 errc;
151 	u32 bitt;
152 	u32 intr;
153 	u32 opt;
154 	u32 brpe;
155 	u32 reserve;
156 	struct pch_can_if_regs ifregs[2]; /* [0]=if1  [1]=if2 */
157 	u32 reserve1[8];
158 	u32 treq1;
159 	u32 treq2;
160 	u32 reserve2[6];
161 	u32 data1;
162 	u32 data2;
163 	u32 reserve3[6];
164 	u32 canipend1;
165 	u32 canipend2;
166 	u32 reserve4[6];
167 	u32 canmval1;
168 	u32 canmval2;
169 	u32 reserve5[37];
170 	u32 srst;
171 };
172 
173 struct pch_can_priv {
174 	struct can_priv can;
175 	struct pci_dev *dev;
176 	u32 tx_enable[PCH_TX_OBJ_END];
177 	u32 rx_enable[PCH_TX_OBJ_END];
178 	u32 rx_link[PCH_TX_OBJ_END];
179 	u32 int_enables;
180 	struct net_device *ndev;
181 	struct pch_can_regs __iomem *regs;
182 	struct napi_struct napi;
183 	int tx_obj;	/* Point next Tx Obj index */
184 	int use_msi;
185 };
186 
187 static struct can_bittiming_const pch_can_bittiming_const = {
188 	.name = KBUILD_MODNAME,
189 	.tseg1_min = 2,
190 	.tseg1_max = 16,
191 	.tseg2_min = 1,
192 	.tseg2_max = 8,
193 	.sjw_max = 4,
194 	.brp_min = 1,
195 	.brp_max = 1024, /* 6bit + extended 4bit */
196 	.brp_inc = 1,
197 };
198 
199 static DEFINE_PCI_DEVICE_TABLE(pch_pci_tbl) = {
200 	{PCI_VENDOR_ID_INTEL, 0x8818, PCI_ANY_ID, PCI_ANY_ID,},
201 	{0,}
202 };
203 MODULE_DEVICE_TABLE(pci, pch_pci_tbl);
204 
pch_can_bit_set(void __iomem * addr,u32 mask)205 static inline void pch_can_bit_set(void __iomem *addr, u32 mask)
206 {
207 	iowrite32(ioread32(addr) | mask, addr);
208 }
209 
pch_can_bit_clear(void __iomem * addr,u32 mask)210 static inline void pch_can_bit_clear(void __iomem *addr, u32 mask)
211 {
212 	iowrite32(ioread32(addr) & ~mask, addr);
213 }
214 
pch_can_set_run_mode(struct pch_can_priv * priv,enum pch_can_mode mode)215 static void pch_can_set_run_mode(struct pch_can_priv *priv,
216 				 enum pch_can_mode mode)
217 {
218 	switch (mode) {
219 	case PCH_CAN_RUN:
220 		pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_INIT);
221 		break;
222 
223 	case PCH_CAN_STOP:
224 		pch_can_bit_set(&priv->regs->cont, PCH_CTRL_INIT);
225 		break;
226 
227 	default:
228 		netdev_err(priv->ndev, "%s -> Invalid Mode.\n", __func__);
229 		break;
230 	}
231 }
232 
pch_can_set_optmode(struct pch_can_priv * priv)233 static void pch_can_set_optmode(struct pch_can_priv *priv)
234 {
235 	u32 reg_val = ioread32(&priv->regs->opt);
236 
237 	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
238 		reg_val |= PCH_OPT_SILENT;
239 
240 	if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
241 		reg_val |= PCH_OPT_LBACK;
242 
243 	pch_can_bit_set(&priv->regs->cont, PCH_CTRL_OPT);
244 	iowrite32(reg_val, &priv->regs->opt);
245 }
246 
pch_can_rw_msg_obj(void __iomem * creq_addr,u32 num)247 static void pch_can_rw_msg_obj(void __iomem *creq_addr, u32 num)
248 {
249 	int counter = PCH_COUNTER_LIMIT;
250 	u32 ifx_creq;
251 
252 	iowrite32(num, creq_addr);
253 	while (counter) {
254 		ifx_creq = ioread32(creq_addr) & PCH_IF_CREQ_BUSY;
255 		if (!ifx_creq)
256 			break;
257 		counter--;
258 		udelay(1);
259 	}
260 	if (!counter)
261 		pr_err("%s:IF1 BUSY Flag is set forever.\n", __func__);
262 }
263 
pch_can_set_int_enables(struct pch_can_priv * priv,enum pch_can_mode interrupt_no)264 static void pch_can_set_int_enables(struct pch_can_priv *priv,
265 				    enum pch_can_mode interrupt_no)
266 {
267 	switch (interrupt_no) {
268 	case PCH_CAN_DISABLE:
269 		pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE);
270 		break;
271 
272 	case PCH_CAN_ALL:
273 		pch_can_bit_set(&priv->regs->cont, PCH_CTRL_IE_SIE_EIE);
274 		break;
275 
276 	case PCH_CAN_NONE:
277 		pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE_SIE_EIE);
278 		break;
279 
280 	default:
281 		netdev_err(priv->ndev, "Invalid interrupt number.\n");
282 		break;
283 	}
284 }
285 
pch_can_set_rxtx(struct pch_can_priv * priv,u32 buff_num,int set,enum pch_ifreg dir)286 static void pch_can_set_rxtx(struct pch_can_priv *priv, u32 buff_num,
287 			     int set, enum pch_ifreg dir)
288 {
289 	u32 ie;
290 
291 	if (dir)
292 		ie = PCH_IF_MCONT_TXIE;
293 	else
294 		ie = PCH_IF_MCONT_RXIE;
295 
296 	/* Reading the Msg buffer from Message RAM to IF1/2 registers. */
297 	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[dir].cmask);
298 	pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
299 
300 	/* Setting the IF1/2MASK1 register to access MsgVal and RxIE bits */
301 	iowrite32(PCH_CMASK_RDWR | PCH_CMASK_ARB | PCH_CMASK_CTRL,
302 		  &priv->regs->ifregs[dir].cmask);
303 
304 	if (set) {
305 		/* Setting the MsgVal and RxIE/TxIE bits */
306 		pch_can_bit_set(&priv->regs->ifregs[dir].mcont, ie);
307 		pch_can_bit_set(&priv->regs->ifregs[dir].id2, PCH_ID_MSGVAL);
308 	} else {
309 		/* Clearing the MsgVal and RxIE/TxIE bits */
310 		pch_can_bit_clear(&priv->regs->ifregs[dir].mcont, ie);
311 		pch_can_bit_clear(&priv->regs->ifregs[dir].id2, PCH_ID_MSGVAL);
312 	}
313 
314 	pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
315 }
316 
pch_can_set_rx_all(struct pch_can_priv * priv,int set)317 static void pch_can_set_rx_all(struct pch_can_priv *priv, int set)
318 {
319 	int i;
320 
321 	/* Traversing to obtain the object configured as receivers. */
322 	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++)
323 		pch_can_set_rxtx(priv, i, set, PCH_RX_IFREG);
324 }
325 
pch_can_set_tx_all(struct pch_can_priv * priv,int set)326 static void pch_can_set_tx_all(struct pch_can_priv *priv, int set)
327 {
328 	int i;
329 
330 	/* Traversing to obtain the object configured as transmit object. */
331 	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++)
332 		pch_can_set_rxtx(priv, i, set, PCH_TX_IFREG);
333 }
334 
pch_can_int_pending(struct pch_can_priv * priv)335 static u32 pch_can_int_pending(struct pch_can_priv *priv)
336 {
337 	return ioread32(&priv->regs->intr) & 0xffff;
338 }
339 
pch_can_clear_if_buffers(struct pch_can_priv * priv)340 static void pch_can_clear_if_buffers(struct pch_can_priv *priv)
341 {
342 	int i; /* Msg Obj ID (1~32) */
343 
344 	for (i = PCH_RX_OBJ_START; i <= PCH_TX_OBJ_END; i++) {
345 		iowrite32(PCH_CMASK_RX_TX_SET, &priv->regs->ifregs[0].cmask);
346 		iowrite32(0xffff, &priv->regs->ifregs[0].mask1);
347 		iowrite32(0xffff, &priv->regs->ifregs[0].mask2);
348 		iowrite32(0x0, &priv->regs->ifregs[0].id1);
349 		iowrite32(0x0, &priv->regs->ifregs[0].id2);
350 		iowrite32(0x0, &priv->regs->ifregs[0].mcont);
351 		iowrite32(0x0, &priv->regs->ifregs[0].data[0]);
352 		iowrite32(0x0, &priv->regs->ifregs[0].data[1]);
353 		iowrite32(0x0, &priv->regs->ifregs[0].data[2]);
354 		iowrite32(0x0, &priv->regs->ifregs[0].data[3]);
355 		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK |
356 			  PCH_CMASK_ARB | PCH_CMASK_CTRL,
357 			  &priv->regs->ifregs[0].cmask);
358 		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
359 	}
360 }
361 
pch_can_config_rx_tx_buffers(struct pch_can_priv * priv)362 static void pch_can_config_rx_tx_buffers(struct pch_can_priv *priv)
363 {
364 	int i;
365 
366 	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
367 		iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
368 		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
369 
370 		iowrite32(0x0, &priv->regs->ifregs[0].id1);
371 		iowrite32(0x0, &priv->regs->ifregs[0].id2);
372 
373 		pch_can_bit_set(&priv->regs->ifregs[0].mcont,
374 				PCH_IF_MCONT_UMASK);
375 
376 		/* In case FIFO mode, Last EoB of Rx Obj must be 1 */
377 		if (i == PCH_RX_OBJ_END)
378 			pch_can_bit_set(&priv->regs->ifregs[0].mcont,
379 					PCH_IF_MCONT_EOB);
380 		else
381 			pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
382 					  PCH_IF_MCONT_EOB);
383 
384 		iowrite32(0, &priv->regs->ifregs[0].mask1);
385 		pch_can_bit_clear(&priv->regs->ifregs[0].mask2,
386 				  0x1fff | PCH_MASK2_MDIR_MXTD);
387 
388 		/* Setting CMASK for writing */
389 		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK | PCH_CMASK_ARB |
390 			  PCH_CMASK_CTRL, &priv->regs->ifregs[0].cmask);
391 
392 		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, i);
393 	}
394 
395 	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++) {
396 		iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[1].cmask);
397 		pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, i);
398 
399 		/* Resetting DIR bit for reception */
400 		iowrite32(0x0, &priv->regs->ifregs[1].id1);
401 		iowrite32(PCH_ID2_DIR, &priv->regs->ifregs[1].id2);
402 
403 		/* Setting EOB bit for transmitter */
404 		iowrite32(PCH_IF_MCONT_EOB | PCH_IF_MCONT_UMASK,
405 			  &priv->regs->ifregs[1].mcont);
406 
407 		iowrite32(0, &priv->regs->ifregs[1].mask1);
408 		pch_can_bit_clear(&priv->regs->ifregs[1].mask2, 0x1fff);
409 
410 		/* Setting CMASK for writing */
411 		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_MASK | PCH_CMASK_ARB |
412 			  PCH_CMASK_CTRL, &priv->regs->ifregs[1].cmask);
413 
414 		pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, i);
415 	}
416 }
417 
pch_can_init(struct pch_can_priv * priv)418 static void pch_can_init(struct pch_can_priv *priv)
419 {
420 	/* Stopping the Can device. */
421 	pch_can_set_run_mode(priv, PCH_CAN_STOP);
422 
423 	/* Clearing all the message object buffers. */
424 	pch_can_clear_if_buffers(priv);
425 
426 	/* Configuring the respective message object as either rx/tx object. */
427 	pch_can_config_rx_tx_buffers(priv);
428 
429 	/* Enabling the interrupts. */
430 	pch_can_set_int_enables(priv, PCH_CAN_ALL);
431 }
432 
pch_can_release(struct pch_can_priv * priv)433 static void pch_can_release(struct pch_can_priv *priv)
434 {
435 	/* Stooping the CAN device. */
436 	pch_can_set_run_mode(priv, PCH_CAN_STOP);
437 
438 	/* Disabling the interrupts. */
439 	pch_can_set_int_enables(priv, PCH_CAN_NONE);
440 
441 	/* Disabling all the receive object. */
442 	pch_can_set_rx_all(priv, 0);
443 
444 	/* Disabling all the transmit object. */
445 	pch_can_set_tx_all(priv, 0);
446 }
447 
448 /* This function clears interrupt(s) from the CAN device. */
pch_can_int_clr(struct pch_can_priv * priv,u32 mask)449 static void pch_can_int_clr(struct pch_can_priv *priv, u32 mask)
450 {
451 	/* Clear interrupt for transmit object */
452 	if ((mask >= PCH_RX_OBJ_START) && (mask <= PCH_RX_OBJ_END)) {
453 		/* Setting CMASK for clearing the reception interrupts. */
454 		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL | PCH_CMASK_ARB,
455 			  &priv->regs->ifregs[0].cmask);
456 
457 		/* Clearing the Dir bit. */
458 		pch_can_bit_clear(&priv->regs->ifregs[0].id2, PCH_ID2_DIR);
459 
460 		/* Clearing NewDat & IntPnd */
461 		pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
462 				  PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_INTPND);
463 
464 		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, mask);
465 	} else if ((mask >= PCH_TX_OBJ_START) && (mask <= PCH_TX_OBJ_END)) {
466 		/*
467 		 * Setting CMASK for clearing interrupts for frame transmission.
468 		 */
469 		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL | PCH_CMASK_ARB,
470 			  &priv->regs->ifregs[1].cmask);
471 
472 		/* Resetting the ID registers. */
473 		pch_can_bit_set(&priv->regs->ifregs[1].id2,
474 			       PCH_ID2_DIR | (0x7ff << 2));
475 		iowrite32(0x0, &priv->regs->ifregs[1].id1);
476 
477 		/* Claring NewDat, TxRqst & IntPnd */
478 		pch_can_bit_clear(&priv->regs->ifregs[1].mcont,
479 				  PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_INTPND |
480 				  PCH_IF_MCONT_TXRQXT);
481 		pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, mask);
482 	}
483 }
484 
pch_can_reset(struct pch_can_priv * priv)485 static void pch_can_reset(struct pch_can_priv *priv)
486 {
487 	/* write to sw reset register */
488 	iowrite32(1, &priv->regs->srst);
489 	iowrite32(0, &priv->regs->srst);
490 }
491 
pch_can_error(struct net_device * ndev,u32 status)492 static void pch_can_error(struct net_device *ndev, u32 status)
493 {
494 	struct sk_buff *skb;
495 	struct pch_can_priv *priv = netdev_priv(ndev);
496 	struct can_frame *cf;
497 	u32 errc, lec;
498 	struct net_device_stats *stats = &(priv->ndev->stats);
499 	enum can_state state = priv->can.state;
500 
501 	skb = alloc_can_err_skb(ndev, &cf);
502 	if (!skb)
503 		return;
504 
505 	if (status & PCH_BUS_OFF) {
506 		pch_can_set_tx_all(priv, 0);
507 		pch_can_set_rx_all(priv, 0);
508 		state = CAN_STATE_BUS_OFF;
509 		cf->can_id |= CAN_ERR_BUSOFF;
510 		can_bus_off(ndev);
511 	}
512 
513 	errc = ioread32(&priv->regs->errc);
514 	/* Warning interrupt. */
515 	if (status & PCH_EWARN) {
516 		state = CAN_STATE_ERROR_WARNING;
517 		priv->can.can_stats.error_warning++;
518 		cf->can_id |= CAN_ERR_CRTL;
519 		if (((errc & PCH_REC) >> 8) > 96)
520 			cf->data[1] |= CAN_ERR_CRTL_RX_WARNING;
521 		if ((errc & PCH_TEC) > 96)
522 			cf->data[1] |= CAN_ERR_CRTL_TX_WARNING;
523 		netdev_dbg(ndev,
524 			"%s -> Error Counter is more than 96.\n", __func__);
525 	}
526 	/* Error passive interrupt. */
527 	if (status & PCH_EPASSIV) {
528 		priv->can.can_stats.error_passive++;
529 		state = CAN_STATE_ERROR_PASSIVE;
530 		cf->can_id |= CAN_ERR_CRTL;
531 		if (errc & PCH_RP)
532 			cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE;
533 		if ((errc & PCH_TEC) > 127)
534 			cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE;
535 		netdev_dbg(ndev,
536 			"%s -> CAN controller is ERROR PASSIVE .\n", __func__);
537 	}
538 
539 	lec = status & PCH_LEC_ALL;
540 	switch (lec) {
541 	case PCH_STUF_ERR:
542 		cf->data[2] |= CAN_ERR_PROT_STUFF;
543 		priv->can.can_stats.bus_error++;
544 		stats->rx_errors++;
545 		break;
546 	case PCH_FORM_ERR:
547 		cf->data[2] |= CAN_ERR_PROT_FORM;
548 		priv->can.can_stats.bus_error++;
549 		stats->rx_errors++;
550 		break;
551 	case PCH_ACK_ERR:
552 		cf->can_id |= CAN_ERR_ACK;
553 		priv->can.can_stats.bus_error++;
554 		stats->rx_errors++;
555 		break;
556 	case PCH_BIT1_ERR:
557 	case PCH_BIT0_ERR:
558 		cf->data[2] |= CAN_ERR_PROT_BIT;
559 		priv->can.can_stats.bus_error++;
560 		stats->rx_errors++;
561 		break;
562 	case PCH_CRC_ERR:
563 		cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ |
564 			       CAN_ERR_PROT_LOC_CRC_DEL;
565 		priv->can.can_stats.bus_error++;
566 		stats->rx_errors++;
567 		break;
568 	case PCH_LEC_ALL: /* Written by CPU. No error status */
569 		break;
570 	}
571 
572 	cf->data[6] = errc & PCH_TEC;
573 	cf->data[7] = (errc & PCH_REC) >> 8;
574 
575 	priv->can.state = state;
576 	netif_receive_skb(skb);
577 
578 	stats->rx_packets++;
579 	stats->rx_bytes += cf->can_dlc;
580 }
581 
pch_can_interrupt(int irq,void * dev_id)582 static irqreturn_t pch_can_interrupt(int irq, void *dev_id)
583 {
584 	struct net_device *ndev = (struct net_device *)dev_id;
585 	struct pch_can_priv *priv = netdev_priv(ndev);
586 
587 	if (!pch_can_int_pending(priv))
588 		return IRQ_NONE;
589 
590 	pch_can_set_int_enables(priv, PCH_CAN_NONE);
591 	napi_schedule(&priv->napi);
592 	return IRQ_HANDLED;
593 }
594 
pch_fifo_thresh(struct pch_can_priv * priv,int obj_id)595 static void pch_fifo_thresh(struct pch_can_priv *priv, int obj_id)
596 {
597 	if (obj_id < PCH_FIFO_THRESH) {
598 		iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL |
599 			  PCH_CMASK_ARB, &priv->regs->ifregs[0].cmask);
600 
601 		/* Clearing the Dir bit. */
602 		pch_can_bit_clear(&priv->regs->ifregs[0].id2, PCH_ID2_DIR);
603 
604 		/* Clearing NewDat & IntPnd */
605 		pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
606 				  PCH_IF_MCONT_INTPND);
607 		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_id);
608 	} else if (obj_id > PCH_FIFO_THRESH) {
609 		pch_can_int_clr(priv, obj_id);
610 	} else if (obj_id == PCH_FIFO_THRESH) {
611 		int cnt;
612 		for (cnt = 0; cnt < PCH_FIFO_THRESH; cnt++)
613 			pch_can_int_clr(priv, cnt + 1);
614 	}
615 }
616 
pch_can_rx_msg_lost(struct net_device * ndev,int obj_id)617 static void pch_can_rx_msg_lost(struct net_device *ndev, int obj_id)
618 {
619 	struct pch_can_priv *priv = netdev_priv(ndev);
620 	struct net_device_stats *stats = &(priv->ndev->stats);
621 	struct sk_buff *skb;
622 	struct can_frame *cf;
623 
624 	netdev_dbg(priv->ndev, "Msg Obj is overwritten.\n");
625 	pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
626 			  PCH_IF_MCONT_MSGLOST);
627 	iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL,
628 		  &priv->regs->ifregs[0].cmask);
629 	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_id);
630 
631 	skb = alloc_can_err_skb(ndev, &cf);
632 	if (!skb)
633 		return;
634 
635 	cf->can_id |= CAN_ERR_CRTL;
636 	cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
637 	stats->rx_over_errors++;
638 	stats->rx_errors++;
639 
640 	netif_receive_skb(skb);
641 }
642 
pch_can_rx_normal(struct net_device * ndev,u32 obj_num,int quota)643 static int pch_can_rx_normal(struct net_device *ndev, u32 obj_num, int quota)
644 {
645 	u32 reg;
646 	canid_t id;
647 	int rcv_pkts = 0;
648 	struct sk_buff *skb;
649 	struct can_frame *cf;
650 	struct pch_can_priv *priv = netdev_priv(ndev);
651 	struct net_device_stats *stats = &(priv->ndev->stats);
652 	int i;
653 	u32 id2;
654 	u16 data_reg;
655 
656 	do {
657 		/* Reading the message object from the Message RAM */
658 		iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
659 		pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, obj_num);
660 
661 		/* Reading the MCONT register. */
662 		reg = ioread32(&priv->regs->ifregs[0].mcont);
663 
664 		if (reg & PCH_IF_MCONT_EOB)
665 			break;
666 
667 		/* If MsgLost bit set. */
668 		if (reg & PCH_IF_MCONT_MSGLOST) {
669 			pch_can_rx_msg_lost(ndev, obj_num);
670 			rcv_pkts++;
671 			quota--;
672 			obj_num++;
673 			continue;
674 		} else if (!(reg & PCH_IF_MCONT_NEWDAT)) {
675 			obj_num++;
676 			continue;
677 		}
678 
679 		skb = alloc_can_skb(priv->ndev, &cf);
680 		if (!skb) {
681 			netdev_err(ndev, "alloc_can_skb Failed\n");
682 			return rcv_pkts;
683 		}
684 
685 		/* Get Received data */
686 		id2 = ioread32(&priv->regs->ifregs[0].id2);
687 		if (id2 & PCH_ID2_XTD) {
688 			id = (ioread32(&priv->regs->ifregs[0].id1) & 0xffff);
689 			id |= (((id2) & 0x1fff) << 16);
690 			cf->can_id = id | CAN_EFF_FLAG;
691 		} else {
692 			id = (id2 >> 2) & CAN_SFF_MASK;
693 			cf->can_id = id;
694 		}
695 
696 		if (id2 & PCH_ID2_DIR)
697 			cf->can_id |= CAN_RTR_FLAG;
698 
699 		cf->can_dlc = get_can_dlc((ioread32(&priv->regs->
700 						    ifregs[0].mcont)) & 0xF);
701 
702 		for (i = 0; i < cf->can_dlc; i += 2) {
703 			data_reg = ioread16(&priv->regs->ifregs[0].data[i / 2]);
704 			cf->data[i] = data_reg;
705 			cf->data[i + 1] = data_reg >> 8;
706 		}
707 
708 		netif_receive_skb(skb);
709 		rcv_pkts++;
710 		stats->rx_packets++;
711 		quota--;
712 		stats->rx_bytes += cf->can_dlc;
713 
714 		pch_fifo_thresh(priv, obj_num);
715 		obj_num++;
716 	} while (quota > 0);
717 
718 	return rcv_pkts;
719 }
720 
pch_can_tx_complete(struct net_device * ndev,u32 int_stat)721 static void pch_can_tx_complete(struct net_device *ndev, u32 int_stat)
722 {
723 	struct pch_can_priv *priv = netdev_priv(ndev);
724 	struct net_device_stats *stats = &(priv->ndev->stats);
725 	u32 dlc;
726 
727 	can_get_echo_skb(ndev, int_stat - PCH_RX_OBJ_END - 1);
728 	iowrite32(PCH_CMASK_RX_TX_GET | PCH_CMASK_CLRINTPND,
729 		  &priv->regs->ifregs[1].cmask);
730 	pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, int_stat);
731 	dlc = get_can_dlc(ioread32(&priv->regs->ifregs[1].mcont) &
732 			  PCH_IF_MCONT_DLC);
733 	stats->tx_bytes += dlc;
734 	stats->tx_packets++;
735 	if (int_stat == PCH_TX_OBJ_END)
736 		netif_wake_queue(ndev);
737 }
738 
pch_can_poll(struct napi_struct * napi,int quota)739 static int pch_can_poll(struct napi_struct *napi, int quota)
740 {
741 	struct net_device *ndev = napi->dev;
742 	struct pch_can_priv *priv = netdev_priv(ndev);
743 	u32 int_stat;
744 	u32 reg_stat;
745 	int quota_save = quota;
746 
747 	int_stat = pch_can_int_pending(priv);
748 	if (!int_stat)
749 		goto end;
750 
751 	if (int_stat == PCH_STATUS_INT) {
752 		reg_stat = ioread32(&priv->regs->stat);
753 
754 		if ((reg_stat & (PCH_BUS_OFF | PCH_LEC_ALL)) &&
755 		   ((reg_stat & PCH_LEC_ALL) != PCH_LEC_ALL)) {
756 			pch_can_error(ndev, reg_stat);
757 			quota--;
758 		}
759 
760 		if (reg_stat & (PCH_TX_OK | PCH_RX_OK))
761 			pch_can_bit_clear(&priv->regs->stat,
762 					  reg_stat & (PCH_TX_OK | PCH_RX_OK));
763 
764 		int_stat = pch_can_int_pending(priv);
765 	}
766 
767 	if (quota == 0)
768 		goto end;
769 
770 	if ((int_stat >= PCH_RX_OBJ_START) && (int_stat <= PCH_RX_OBJ_END)) {
771 		quota -= pch_can_rx_normal(ndev, int_stat, quota);
772 	} else if ((int_stat >= PCH_TX_OBJ_START) &&
773 		   (int_stat <= PCH_TX_OBJ_END)) {
774 		/* Handle transmission interrupt */
775 		pch_can_tx_complete(ndev, int_stat);
776 	}
777 
778 end:
779 	napi_complete(napi);
780 	pch_can_set_int_enables(priv, PCH_CAN_ALL);
781 
782 	return quota_save - quota;
783 }
784 
pch_set_bittiming(struct net_device * ndev)785 static int pch_set_bittiming(struct net_device *ndev)
786 {
787 	struct pch_can_priv *priv = netdev_priv(ndev);
788 	const struct can_bittiming *bt = &priv->can.bittiming;
789 	u32 canbit;
790 	u32 bepe;
791 
792 	/* Setting the CCE bit for accessing the Can Timing register. */
793 	pch_can_bit_set(&priv->regs->cont, PCH_CTRL_CCE);
794 
795 	canbit = (bt->brp - 1) & PCH_MSK_BITT_BRP;
796 	canbit |= (bt->sjw - 1) << PCH_BIT_SJW_SHIFT;
797 	canbit |= (bt->phase_seg1 + bt->prop_seg - 1) << PCH_BIT_TSEG1_SHIFT;
798 	canbit |= (bt->phase_seg2 - 1) << PCH_BIT_TSEG2_SHIFT;
799 	bepe = ((bt->brp - 1) & PCH_MSK_BRPE_BRPE) >> PCH_BIT_BRPE_BRPE_SHIFT;
800 	iowrite32(canbit, &priv->regs->bitt);
801 	iowrite32(bepe, &priv->regs->brpe);
802 	pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_CCE);
803 
804 	return 0;
805 }
806 
pch_can_start(struct net_device * ndev)807 static void pch_can_start(struct net_device *ndev)
808 {
809 	struct pch_can_priv *priv = netdev_priv(ndev);
810 
811 	if (priv->can.state != CAN_STATE_STOPPED)
812 		pch_can_reset(priv);
813 
814 	pch_set_bittiming(ndev);
815 	pch_can_set_optmode(priv);
816 
817 	pch_can_set_tx_all(priv, 1);
818 	pch_can_set_rx_all(priv, 1);
819 
820 	/* Setting the CAN to run mode. */
821 	pch_can_set_run_mode(priv, PCH_CAN_RUN);
822 
823 	priv->can.state = CAN_STATE_ERROR_ACTIVE;
824 
825 	return;
826 }
827 
pch_can_do_set_mode(struct net_device * ndev,enum can_mode mode)828 static int pch_can_do_set_mode(struct net_device *ndev, enum can_mode mode)
829 {
830 	int ret = 0;
831 
832 	switch (mode) {
833 	case CAN_MODE_START:
834 		pch_can_start(ndev);
835 		netif_wake_queue(ndev);
836 		break;
837 	default:
838 		ret = -EOPNOTSUPP;
839 		break;
840 	}
841 
842 	return ret;
843 }
844 
pch_can_open(struct net_device * ndev)845 static int pch_can_open(struct net_device *ndev)
846 {
847 	struct pch_can_priv *priv = netdev_priv(ndev);
848 	int retval;
849 
850 	/* Regstering the interrupt. */
851 	retval = request_irq(priv->dev->irq, pch_can_interrupt, IRQF_SHARED,
852 			     ndev->name, ndev);
853 	if (retval) {
854 		netdev_err(ndev, "request_irq failed.\n");
855 		goto req_irq_err;
856 	}
857 
858 	/* Open common can device */
859 	retval = open_candev(ndev);
860 	if (retval) {
861 		netdev_err(ndev, "open_candev() failed %d\n", retval);
862 		goto err_open_candev;
863 	}
864 
865 	pch_can_init(priv);
866 	pch_can_start(ndev);
867 	napi_enable(&priv->napi);
868 	netif_start_queue(ndev);
869 
870 	return 0;
871 
872 err_open_candev:
873 	free_irq(priv->dev->irq, ndev);
874 req_irq_err:
875 	pch_can_release(priv);
876 
877 	return retval;
878 }
879 
pch_close(struct net_device * ndev)880 static int pch_close(struct net_device *ndev)
881 {
882 	struct pch_can_priv *priv = netdev_priv(ndev);
883 
884 	netif_stop_queue(ndev);
885 	napi_disable(&priv->napi);
886 	pch_can_release(priv);
887 	free_irq(priv->dev->irq, ndev);
888 	close_candev(ndev);
889 	priv->can.state = CAN_STATE_STOPPED;
890 	return 0;
891 }
892 
pch_xmit(struct sk_buff * skb,struct net_device * ndev)893 static netdev_tx_t pch_xmit(struct sk_buff *skb, struct net_device *ndev)
894 {
895 	struct pch_can_priv *priv = netdev_priv(ndev);
896 	struct can_frame *cf = (struct can_frame *)skb->data;
897 	int tx_obj_no;
898 	int i;
899 	u32 id2;
900 
901 	if (can_dropped_invalid_skb(ndev, skb))
902 		return NETDEV_TX_OK;
903 
904 	tx_obj_no = priv->tx_obj;
905 	if (priv->tx_obj == PCH_TX_OBJ_END) {
906 		if (ioread32(&priv->regs->treq2) & PCH_TREQ2_TX_MASK)
907 			netif_stop_queue(ndev);
908 
909 		priv->tx_obj = PCH_TX_OBJ_START;
910 	} else {
911 		priv->tx_obj++;
912 	}
913 
914 	/* Setting the CMASK register. */
915 	pch_can_bit_set(&priv->regs->ifregs[1].cmask, PCH_CMASK_ALL);
916 
917 	/* If ID extended is set. */
918 	if (cf->can_id & CAN_EFF_FLAG) {
919 		iowrite32(cf->can_id & 0xffff, &priv->regs->ifregs[1].id1);
920 		id2 = ((cf->can_id >> 16) & 0x1fff) | PCH_ID2_XTD;
921 	} else {
922 		iowrite32(0, &priv->regs->ifregs[1].id1);
923 		id2 = (cf->can_id & CAN_SFF_MASK) << 2;
924 	}
925 
926 	id2 |= PCH_ID_MSGVAL;
927 
928 	/* If remote frame has to be transmitted.. */
929 	if (!(cf->can_id & CAN_RTR_FLAG))
930 		id2 |= PCH_ID2_DIR;
931 
932 	iowrite32(id2, &priv->regs->ifregs[1].id2);
933 
934 	/* Copy data to register */
935 	for (i = 0; i < cf->can_dlc; i += 2) {
936 		iowrite16(cf->data[i] | (cf->data[i + 1] << 8),
937 			  &priv->regs->ifregs[1].data[i / 2]);
938 	}
939 
940 	can_put_echo_skb(skb, ndev, tx_obj_no - PCH_RX_OBJ_END - 1);
941 
942 	/* Set the size of the data. Update if2_mcont */
943 	iowrite32(cf->can_dlc | PCH_IF_MCONT_NEWDAT | PCH_IF_MCONT_TXRQXT |
944 		  PCH_IF_MCONT_TXIE, &priv->regs->ifregs[1].mcont);
945 
946 	pch_can_rw_msg_obj(&priv->regs->ifregs[1].creq, tx_obj_no);
947 
948 	return NETDEV_TX_OK;
949 }
950 
951 static const struct net_device_ops pch_can_netdev_ops = {
952 	.ndo_open		= pch_can_open,
953 	.ndo_stop		= pch_close,
954 	.ndo_start_xmit		= pch_xmit,
955 };
956 
pch_can_remove(struct pci_dev * pdev)957 static void __devexit pch_can_remove(struct pci_dev *pdev)
958 {
959 	struct net_device *ndev = pci_get_drvdata(pdev);
960 	struct pch_can_priv *priv = netdev_priv(ndev);
961 
962 	unregister_candev(priv->ndev);
963 	if (priv->use_msi)
964 		pci_disable_msi(priv->dev);
965 	pci_release_regions(pdev);
966 	pci_disable_device(pdev);
967 	pci_set_drvdata(pdev, NULL);
968 	pch_can_reset(priv);
969 	pci_iounmap(pdev, priv->regs);
970 	free_candev(priv->ndev);
971 }
972 
973 #ifdef CONFIG_PM
pch_can_set_int_custom(struct pch_can_priv * priv)974 static void pch_can_set_int_custom(struct pch_can_priv *priv)
975 {
976 	/* Clearing the IE, SIE and EIE bits of Can control register. */
977 	pch_can_bit_clear(&priv->regs->cont, PCH_CTRL_IE_SIE_EIE);
978 
979 	/* Appropriately setting them. */
980 	pch_can_bit_set(&priv->regs->cont,
981 			((priv->int_enables & PCH_MSK_CTRL_IE_SIE_EIE) << 1));
982 }
983 
984 /* This function retrieves interrupt enabled for the CAN device. */
pch_can_get_int_enables(struct pch_can_priv * priv)985 static u32 pch_can_get_int_enables(struct pch_can_priv *priv)
986 {
987 	/* Obtaining the status of IE, SIE and EIE interrupt bits. */
988 	return (ioread32(&priv->regs->cont) & PCH_CTRL_IE_SIE_EIE) >> 1;
989 }
990 
pch_can_get_rxtx_ir(struct pch_can_priv * priv,u32 buff_num,enum pch_ifreg dir)991 static u32 pch_can_get_rxtx_ir(struct pch_can_priv *priv, u32 buff_num,
992 			       enum pch_ifreg dir)
993 {
994 	u32 ie, enable;
995 
996 	if (dir)
997 		ie = PCH_IF_MCONT_RXIE;
998 	else
999 		ie = PCH_IF_MCONT_TXIE;
1000 
1001 	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[dir].cmask);
1002 	pch_can_rw_msg_obj(&priv->regs->ifregs[dir].creq, buff_num);
1003 
1004 	if (((ioread32(&priv->regs->ifregs[dir].id2)) & PCH_ID_MSGVAL) &&
1005 			((ioread32(&priv->regs->ifregs[dir].mcont)) & ie))
1006 		enable = 1;
1007 	else
1008 		enable = 0;
1009 
1010 	return enable;
1011 }
1012 
pch_can_set_rx_buffer_link(struct pch_can_priv * priv,u32 buffer_num,int set)1013 static void pch_can_set_rx_buffer_link(struct pch_can_priv *priv,
1014 				       u32 buffer_num, int set)
1015 {
1016 	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
1017 	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
1018 	iowrite32(PCH_CMASK_RDWR | PCH_CMASK_CTRL,
1019 		  &priv->regs->ifregs[0].cmask);
1020 	if (set)
1021 		pch_can_bit_clear(&priv->regs->ifregs[0].mcont,
1022 				  PCH_IF_MCONT_EOB);
1023 	else
1024 		pch_can_bit_set(&priv->regs->ifregs[0].mcont, PCH_IF_MCONT_EOB);
1025 
1026 	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
1027 }
1028 
pch_can_get_rx_buffer_link(struct pch_can_priv * priv,u32 buffer_num)1029 static u32 pch_can_get_rx_buffer_link(struct pch_can_priv *priv, u32 buffer_num)
1030 {
1031 	u32 link;
1032 
1033 	iowrite32(PCH_CMASK_RX_TX_GET, &priv->regs->ifregs[0].cmask);
1034 	pch_can_rw_msg_obj(&priv->regs->ifregs[0].creq, buffer_num);
1035 
1036 	if (ioread32(&priv->regs->ifregs[0].mcont) & PCH_IF_MCONT_EOB)
1037 		link = 0;
1038 	else
1039 		link = 1;
1040 	return link;
1041 }
1042 
pch_can_get_buffer_status(struct pch_can_priv * priv)1043 static int pch_can_get_buffer_status(struct pch_can_priv *priv)
1044 {
1045 	return (ioread32(&priv->regs->treq1) & 0xffff) |
1046 	       (ioread32(&priv->regs->treq2) << 16);
1047 }
1048 
pch_can_suspend(struct pci_dev * pdev,pm_message_t state)1049 static int pch_can_suspend(struct pci_dev *pdev, pm_message_t state)
1050 {
1051 	int i;
1052 	int retval;
1053 	u32 buf_stat;	/* Variable for reading the transmit buffer status. */
1054 	int counter = PCH_COUNTER_LIMIT;
1055 
1056 	struct net_device *dev = pci_get_drvdata(pdev);
1057 	struct pch_can_priv *priv = netdev_priv(dev);
1058 
1059 	/* Stop the CAN controller */
1060 	pch_can_set_run_mode(priv, PCH_CAN_STOP);
1061 
1062 	/* Indicate that we are aboutto/in suspend */
1063 	priv->can.state = CAN_STATE_STOPPED;
1064 
1065 	/* Waiting for all transmission to complete. */
1066 	while (counter) {
1067 		buf_stat = pch_can_get_buffer_status(priv);
1068 		if (!buf_stat)
1069 			break;
1070 		counter--;
1071 		udelay(1);
1072 	}
1073 	if (!counter)
1074 		dev_err(&pdev->dev, "%s -> Transmission time out.\n", __func__);
1075 
1076 	/* Save interrupt configuration and then disable them */
1077 	priv->int_enables = pch_can_get_int_enables(priv);
1078 	pch_can_set_int_enables(priv, PCH_CAN_DISABLE);
1079 
1080 	/* Save Tx buffer enable state */
1081 	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++)
1082 		priv->tx_enable[i - 1] = pch_can_get_rxtx_ir(priv, i,
1083 							     PCH_TX_IFREG);
1084 
1085 	/* Disable all Transmit buffers */
1086 	pch_can_set_tx_all(priv, 0);
1087 
1088 	/* Save Rx buffer enable state */
1089 	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
1090 		priv->rx_enable[i - 1] = pch_can_get_rxtx_ir(priv, i,
1091 							     PCH_RX_IFREG);
1092 		priv->rx_link[i - 1] = pch_can_get_rx_buffer_link(priv, i);
1093 	}
1094 
1095 	/* Disable all Receive buffers */
1096 	pch_can_set_rx_all(priv, 0);
1097 	retval = pci_save_state(pdev);
1098 	if (retval) {
1099 		dev_err(&pdev->dev, "pci_save_state failed.\n");
1100 	} else {
1101 		pci_enable_wake(pdev, PCI_D3hot, 0);
1102 		pci_disable_device(pdev);
1103 		pci_set_power_state(pdev, pci_choose_state(pdev, state));
1104 	}
1105 
1106 	return retval;
1107 }
1108 
pch_can_resume(struct pci_dev * pdev)1109 static int pch_can_resume(struct pci_dev *pdev)
1110 {
1111 	int i;
1112 	int retval;
1113 	struct net_device *dev = pci_get_drvdata(pdev);
1114 	struct pch_can_priv *priv = netdev_priv(dev);
1115 
1116 	pci_set_power_state(pdev, PCI_D0);
1117 	pci_restore_state(pdev);
1118 	retval = pci_enable_device(pdev);
1119 	if (retval) {
1120 		dev_err(&pdev->dev, "pci_enable_device failed.\n");
1121 		return retval;
1122 	}
1123 
1124 	pci_enable_wake(pdev, PCI_D3hot, 0);
1125 
1126 	priv->can.state = CAN_STATE_ERROR_ACTIVE;
1127 
1128 	/* Disabling all interrupts. */
1129 	pch_can_set_int_enables(priv, PCH_CAN_DISABLE);
1130 
1131 	/* Setting the CAN device in Stop Mode. */
1132 	pch_can_set_run_mode(priv, PCH_CAN_STOP);
1133 
1134 	/* Configuring the transmit and receive buffers. */
1135 	pch_can_config_rx_tx_buffers(priv);
1136 
1137 	/* Restore the CAN state */
1138 	pch_set_bittiming(dev);
1139 
1140 	/* Listen/Active */
1141 	pch_can_set_optmode(priv);
1142 
1143 	/* Enabling the transmit buffer. */
1144 	for (i = PCH_TX_OBJ_START; i <= PCH_TX_OBJ_END; i++)
1145 		pch_can_set_rxtx(priv, i, priv->tx_enable[i - 1], PCH_TX_IFREG);
1146 
1147 	/* Configuring the receive buffer and enabling them. */
1148 	for (i = PCH_RX_OBJ_START; i <= PCH_RX_OBJ_END; i++) {
1149 		/* Restore buffer link */
1150 		pch_can_set_rx_buffer_link(priv, i, priv->rx_link[i - 1]);
1151 
1152 		/* Restore buffer enables */
1153 		pch_can_set_rxtx(priv, i, priv->rx_enable[i - 1], PCH_RX_IFREG);
1154 	}
1155 
1156 	/* Enable CAN Interrupts */
1157 	pch_can_set_int_custom(priv);
1158 
1159 	/* Restore Run Mode */
1160 	pch_can_set_run_mode(priv, PCH_CAN_RUN);
1161 
1162 	return retval;
1163 }
1164 #else
1165 #define pch_can_suspend NULL
1166 #define pch_can_resume NULL
1167 #endif
1168 
pch_can_get_berr_counter(const struct net_device * dev,struct can_berr_counter * bec)1169 static int pch_can_get_berr_counter(const struct net_device *dev,
1170 				    struct can_berr_counter *bec)
1171 {
1172 	struct pch_can_priv *priv = netdev_priv(dev);
1173 	u32 errc = ioread32(&priv->regs->errc);
1174 
1175 	bec->txerr = errc & PCH_TEC;
1176 	bec->rxerr = (errc & PCH_REC) >> 8;
1177 
1178 	return 0;
1179 }
1180 
pch_can_probe(struct pci_dev * pdev,const struct pci_device_id * id)1181 static int __devinit pch_can_probe(struct pci_dev *pdev,
1182 				   const struct pci_device_id *id)
1183 {
1184 	struct net_device *ndev;
1185 	struct pch_can_priv *priv;
1186 	int rc;
1187 	void __iomem *addr;
1188 
1189 	rc = pci_enable_device(pdev);
1190 	if (rc) {
1191 		dev_err(&pdev->dev, "Failed pci_enable_device %d\n", rc);
1192 		goto probe_exit_endev;
1193 	}
1194 
1195 	rc = pci_request_regions(pdev, KBUILD_MODNAME);
1196 	if (rc) {
1197 		dev_err(&pdev->dev, "Failed pci_request_regions %d\n", rc);
1198 		goto probe_exit_pcireq;
1199 	}
1200 
1201 	addr = pci_iomap(pdev, 1, 0);
1202 	if (!addr) {
1203 		rc = -EIO;
1204 		dev_err(&pdev->dev, "Failed pci_iomap\n");
1205 		goto probe_exit_ipmap;
1206 	}
1207 
1208 	ndev = alloc_candev(sizeof(struct pch_can_priv), PCH_TX_OBJ_END);
1209 	if (!ndev) {
1210 		rc = -ENOMEM;
1211 		dev_err(&pdev->dev, "Failed alloc_candev\n");
1212 		goto probe_exit_alloc_candev;
1213 	}
1214 
1215 	priv = netdev_priv(ndev);
1216 	priv->ndev = ndev;
1217 	priv->regs = addr;
1218 	priv->dev = pdev;
1219 	priv->can.bittiming_const = &pch_can_bittiming_const;
1220 	priv->can.do_set_mode = pch_can_do_set_mode;
1221 	priv->can.do_get_berr_counter = pch_can_get_berr_counter;
1222 	priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY |
1223 				       CAN_CTRLMODE_LOOPBACK;
1224 	priv->tx_obj = PCH_TX_OBJ_START; /* Point head of Tx Obj */
1225 
1226 	ndev->irq = pdev->irq;
1227 	ndev->flags |= IFF_ECHO;
1228 
1229 	pci_set_drvdata(pdev, ndev);
1230 	SET_NETDEV_DEV(ndev, &pdev->dev);
1231 	ndev->netdev_ops = &pch_can_netdev_ops;
1232 	priv->can.clock.freq = PCH_CAN_CLK; /* Hz */
1233 
1234 	netif_napi_add(ndev, &priv->napi, pch_can_poll, PCH_RX_OBJ_END);
1235 
1236 	rc = pci_enable_msi(priv->dev);
1237 	if (rc) {
1238 		netdev_err(ndev, "PCH CAN opened without MSI\n");
1239 		priv->use_msi = 0;
1240 	} else {
1241 		netdev_err(ndev, "PCH CAN opened with MSI\n");
1242 		pci_set_master(pdev);
1243 		priv->use_msi = 1;
1244 	}
1245 
1246 	rc = register_candev(ndev);
1247 	if (rc) {
1248 		dev_err(&pdev->dev, "Failed register_candev %d\n", rc);
1249 		goto probe_exit_reg_candev;
1250 	}
1251 
1252 	return 0;
1253 
1254 probe_exit_reg_candev:
1255 	if (priv->use_msi)
1256 		pci_disable_msi(priv->dev);
1257 	free_candev(ndev);
1258 probe_exit_alloc_candev:
1259 	pci_iounmap(pdev, addr);
1260 probe_exit_ipmap:
1261 	pci_release_regions(pdev);
1262 probe_exit_pcireq:
1263 	pci_disable_device(pdev);
1264 probe_exit_endev:
1265 	return rc;
1266 }
1267 
1268 static struct pci_driver pch_can_pci_driver = {
1269 	.name = "pch_can",
1270 	.id_table = pch_pci_tbl,
1271 	.probe = pch_can_probe,
1272 	.remove = __devexit_p(pch_can_remove),
1273 	.suspend = pch_can_suspend,
1274 	.resume = pch_can_resume,
1275 };
1276 
pch_can_pci_init(void)1277 static int __init pch_can_pci_init(void)
1278 {
1279 	return pci_register_driver(&pch_can_pci_driver);
1280 }
1281 module_init(pch_can_pci_init);
1282 
pch_can_pci_exit(void)1283 static void __exit pch_can_pci_exit(void)
1284 {
1285 	pci_unregister_driver(&pch_can_pci_driver);
1286 }
1287 module_exit(pch_can_pci_exit);
1288 
1289 MODULE_DESCRIPTION("Intel EG20T PCH CAN(Controller Area Network) Driver");
1290 MODULE_LICENSE("GPL v2");
1291 MODULE_VERSION("0.94");
1292