135e62ae8SThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only
2afa17a50SWolfram Sang /*
3afa17a50SWolfram Sang * CAN bus driver for the alone generic (as possible as) MSCAN controller.
4afa17a50SWolfram Sang *
5afa17a50SWolfram Sang * Copyright (C) 2005-2006 Andrey Volkov <avolkov@varma-el.com>,
6afa17a50SWolfram Sang * Varma Electronics Oy
7afa17a50SWolfram Sang * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
82d4b6fafSWolfgang Grandegger * Copyright (C) 2008-2009 Pengutronix <kernel@pengutronix.de>
9afa17a50SWolfram Sang */
10afa17a50SWolfram Sang
11afa17a50SWolfram Sang #include <linux/kernel.h>
12afa17a50SWolfram Sang #include <linux/module.h>
13afa17a50SWolfram Sang #include <linux/interrupt.h>
14afa17a50SWolfram Sang #include <linux/delay.h>
15afa17a50SWolfram Sang #include <linux/netdevice.h>
16afa17a50SWolfram Sang #include <linux/if_arp.h>
17afa17a50SWolfram Sang #include <linux/if_ether.h>
18afa17a50SWolfram Sang #include <linux/list.h>
19afa17a50SWolfram Sang #include <linux/can/dev.h>
20afa17a50SWolfram Sang #include <linux/can/error.h>
21afa17a50SWolfram Sang #include <linux/io.h>
22afa17a50SWolfram Sang
23afa17a50SWolfram Sang #include "mscan.h"
24afa17a50SWolfram Sang
25194b9a4cSMarc Kleine-Budde static const struct can_bittiming_const mscan_bittiming_const = {
26afa17a50SWolfram Sang .name = "mscan",
27afa17a50SWolfram Sang .tseg1_min = 4,
28afa17a50SWolfram Sang .tseg1_max = 16,
29afa17a50SWolfram Sang .tseg2_min = 2,
30afa17a50SWolfram Sang .tseg2_max = 8,
31afa17a50SWolfram Sang .sjw_max = 4,
32afa17a50SWolfram Sang .brp_min = 1,
33afa17a50SWolfram Sang .brp_max = 64,
34afa17a50SWolfram Sang .brp_inc = 1,
35afa17a50SWolfram Sang };
36afa17a50SWolfram Sang
37afa17a50SWolfram Sang struct mscan_state {
38afa17a50SWolfram Sang u8 mode;
39afa17a50SWolfram Sang u8 canrier;
40afa17a50SWolfram Sang u8 cantier;
41afa17a50SWolfram Sang };
42afa17a50SWolfram Sang
43afa17a50SWolfram Sang static enum can_state state_map[] = {
44afa17a50SWolfram Sang CAN_STATE_ERROR_ACTIVE,
45afa17a50SWolfram Sang CAN_STATE_ERROR_WARNING,
46afa17a50SWolfram Sang CAN_STATE_ERROR_PASSIVE,
47afa17a50SWolfram Sang CAN_STATE_BUS_OFF
48afa17a50SWolfram Sang };
49afa17a50SWolfram Sang
mscan_set_mode(struct net_device * dev,u8 mode)50afa17a50SWolfram Sang static int mscan_set_mode(struct net_device *dev, u8 mode)
51afa17a50SWolfram Sang {
52afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev);
53665d7eb8SMarc Kleine-Budde struct mscan_regs __iomem *regs = priv->reg_base;
54afa17a50SWolfram Sang int ret = 0;
55afa17a50SWolfram Sang int i;
56afa17a50SWolfram Sang u8 canctl1;
57afa17a50SWolfram Sang
58afa17a50SWolfram Sang if (mode != MSCAN_NORMAL_MODE) {
59afa17a50SWolfram Sang if (priv->tx_active) {
60afa17a50SWolfram Sang /* Abort transfers before going to sleep */#
61afa17a50SWolfram Sang out_8(®s->cantarq, priv->tx_active);
62afa17a50SWolfram Sang /* Suppress TX done interrupts */
63afa17a50SWolfram Sang out_8(®s->cantier, 0);
64afa17a50SWolfram Sang }
65afa17a50SWolfram Sang
66afa17a50SWolfram Sang canctl1 = in_8(®s->canctl1);
670285e7ceSWolfram Sang if ((mode & MSCAN_SLPRQ) && !(canctl1 & MSCAN_SLPAK)) {
6859179ea6SWolfram Sang setbits8(®s->canctl0, MSCAN_SLPRQ);
69afa17a50SWolfram Sang for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) {
70afa17a50SWolfram Sang if (in_8(®s->canctl1) & MSCAN_SLPAK)
71afa17a50SWolfram Sang break;
72afa17a50SWolfram Sang udelay(100);
73afa17a50SWolfram Sang }
74afa17a50SWolfram Sang /*
75afa17a50SWolfram Sang * The mscan controller will fail to enter sleep mode,
76afa17a50SWolfram Sang * while there are irregular activities on bus, like
77afa17a50SWolfram Sang * somebody keeps retransmitting. This behavior is
78afa17a50SWolfram Sang * undocumented and seems to differ between mscan built
79afa17a50SWolfram Sang * in mpc5200b and mpc5200. We proceed in that case,
80afa17a50SWolfram Sang * since otherwise the slprq will be kept set and the
81afa17a50SWolfram Sang * controller will get stuck. NOTE: INITRQ or CSWAI
82afa17a50SWolfram Sang * will abort all active transmit actions, if still
83afa17a50SWolfram Sang * any, at once.
84afa17a50SWolfram Sang */
85afa17a50SWolfram Sang if (i >= MSCAN_SET_MODE_RETRIES)
86aabdfd6aSWolfgang Grandegger netdev_dbg(dev,
87afa17a50SWolfram Sang "device failed to enter sleep mode. "
88afa17a50SWolfram Sang "We proceed anyhow.\n");
89afa17a50SWolfram Sang else
90afa17a50SWolfram Sang priv->can.state = CAN_STATE_SLEEPING;
91afa17a50SWolfram Sang }
92afa17a50SWolfram Sang
930285e7ceSWolfram Sang if ((mode & MSCAN_INITRQ) && !(canctl1 & MSCAN_INITAK)) {
9459179ea6SWolfram Sang setbits8(®s->canctl0, MSCAN_INITRQ);
95afa17a50SWolfram Sang for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) {
96afa17a50SWolfram Sang if (in_8(®s->canctl1) & MSCAN_INITAK)
97afa17a50SWolfram Sang break;
98afa17a50SWolfram Sang }
99afa17a50SWolfram Sang if (i >= MSCAN_SET_MODE_RETRIES)
100afa17a50SWolfram Sang ret = -ENODEV;
101afa17a50SWolfram Sang }
102afa17a50SWolfram Sang if (!ret)
103afa17a50SWolfram Sang priv->can.state = CAN_STATE_STOPPED;
104afa17a50SWolfram Sang
105afa17a50SWolfram Sang if (mode & MSCAN_CSWAI)
10659179ea6SWolfram Sang setbits8(®s->canctl0, MSCAN_CSWAI);
107afa17a50SWolfram Sang
108afa17a50SWolfram Sang } else {
109afa17a50SWolfram Sang canctl1 = in_8(®s->canctl1);
110afa17a50SWolfram Sang if (canctl1 & (MSCAN_SLPAK | MSCAN_INITAK)) {
11159179ea6SWolfram Sang clrbits8(®s->canctl0, MSCAN_SLPRQ | MSCAN_INITRQ);
112afa17a50SWolfram Sang for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) {
113afa17a50SWolfram Sang canctl1 = in_8(®s->canctl1);
114afa17a50SWolfram Sang if (!(canctl1 & (MSCAN_INITAK | MSCAN_SLPAK)))
115afa17a50SWolfram Sang break;
116afa17a50SWolfram Sang }
117afa17a50SWolfram Sang if (i >= MSCAN_SET_MODE_RETRIES)
118afa17a50SWolfram Sang ret = -ENODEV;
119afa17a50SWolfram Sang else
120afa17a50SWolfram Sang priv->can.state = CAN_STATE_ERROR_ACTIVE;
121afa17a50SWolfram Sang }
122afa17a50SWolfram Sang }
123afa17a50SWolfram Sang return ret;
124afa17a50SWolfram Sang }
125afa17a50SWolfram Sang
mscan_start(struct net_device * dev)126afa17a50SWolfram Sang static int mscan_start(struct net_device *dev)
127afa17a50SWolfram Sang {
128afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev);
129665d7eb8SMarc Kleine-Budde struct mscan_regs __iomem *regs = priv->reg_base;
130afa17a50SWolfram Sang u8 canrflg;
131afa17a50SWolfram Sang int err;
132afa17a50SWolfram Sang
133afa17a50SWolfram Sang out_8(®s->canrier, 0);
134afa17a50SWolfram Sang
135afa17a50SWolfram Sang INIT_LIST_HEAD(&priv->tx_head);
136afa17a50SWolfram Sang priv->prev_buf_id = 0;
137afa17a50SWolfram Sang priv->cur_pri = 0;
138afa17a50SWolfram Sang priv->tx_active = 0;
139afa17a50SWolfram Sang priv->shadow_canrier = 0;
140afa17a50SWolfram Sang priv->flags = 0;
141afa17a50SWolfram Sang
142bf3af547SWolfgang Grandegger if (priv->type == MSCAN_TYPE_MPC5121) {
143bf3af547SWolfgang Grandegger /* Clear pending bus-off condition */
144bf3af547SWolfgang Grandegger if (in_8(®s->canmisc) & MSCAN_BOHOLD)
145bf3af547SWolfgang Grandegger out_8(®s->canmisc, MSCAN_BOHOLD);
146bf3af547SWolfgang Grandegger }
147bf3af547SWolfgang Grandegger
148afa17a50SWolfram Sang err = mscan_set_mode(dev, MSCAN_NORMAL_MODE);
149afa17a50SWolfram Sang if (err)
150afa17a50SWolfram Sang return err;
151afa17a50SWolfram Sang
152afa17a50SWolfram Sang canrflg = in_8(®s->canrflg);
153afa17a50SWolfram Sang priv->shadow_statflg = canrflg & MSCAN_STAT_MSK;
154afa17a50SWolfram Sang priv->can.state = state_map[max(MSCAN_STATE_RX(canrflg),
155afa17a50SWolfram Sang MSCAN_STATE_TX(canrflg))];
156afa17a50SWolfram Sang out_8(®s->cantier, 0);
157afa17a50SWolfram Sang
158afa17a50SWolfram Sang /* Enable receive interrupts. */
159bf3af547SWolfgang Grandegger out_8(®s->canrier, MSCAN_RX_INTS_ENABLE);
160bf3af547SWolfgang Grandegger
161bf3af547SWolfgang Grandegger return 0;
162bf3af547SWolfgang Grandegger }
163bf3af547SWolfgang Grandegger
mscan_restart(struct net_device * dev)164bf3af547SWolfgang Grandegger static int mscan_restart(struct net_device *dev)
165bf3af547SWolfgang Grandegger {
166bf3af547SWolfgang Grandegger struct mscan_priv *priv = netdev_priv(dev);
167bf3af547SWolfgang Grandegger
168bf3af547SWolfgang Grandegger if (priv->type == MSCAN_TYPE_MPC5121) {
169665d7eb8SMarc Kleine-Budde struct mscan_regs __iomem *regs = priv->reg_base;
170bf3af547SWolfgang Grandegger
171bf3af547SWolfgang Grandegger priv->can.state = CAN_STATE_ERROR_ACTIVE;
172bf3af547SWolfgang Grandegger WARN(!(in_8(®s->canmisc) & MSCAN_BOHOLD),
173c389ff80SJoe Perches "bus-off state expected\n");
174bf3af547SWolfgang Grandegger out_8(®s->canmisc, MSCAN_BOHOLD);
175bf3af547SWolfgang Grandegger /* Re-enable receive interrupts. */
176bf3af547SWolfgang Grandegger out_8(®s->canrier, MSCAN_RX_INTS_ENABLE);
177bf3af547SWolfgang Grandegger } else {
178bf3af547SWolfgang Grandegger if (priv->can.state <= CAN_STATE_BUS_OFF)
179bf3af547SWolfgang Grandegger mscan_set_mode(dev, MSCAN_INIT_MODE);
180bf3af547SWolfgang Grandegger return mscan_start(dev);
181bf3af547SWolfgang Grandegger }
182afa17a50SWolfram Sang
183afa17a50SWolfram Sang return 0;
184afa17a50SWolfram Sang }
185afa17a50SWolfram Sang
mscan_start_xmit(struct sk_buff * skb,struct net_device * dev)186afa17a50SWolfram Sang static netdev_tx_t mscan_start_xmit(struct sk_buff *skb, struct net_device *dev)
187afa17a50SWolfram Sang {
188afa17a50SWolfram Sang struct can_frame *frame = (struct can_frame *)skb->data;
189afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev);
190665d7eb8SMarc Kleine-Budde struct mscan_regs __iomem *regs = priv->reg_base;
191afa17a50SWolfram Sang int i, rtr, buf_id;
192afa17a50SWolfram Sang u32 can_id;
193afa17a50SWolfram Sang
194*ae64438bSOliver Hartkopp if (can_dev_dropped_skb(dev, skb))
1952d4b6fafSWolfgang Grandegger return NETDEV_TX_OK;
196afa17a50SWolfram Sang
197afa17a50SWolfram Sang out_8(®s->cantier, 0);
198afa17a50SWolfram Sang
199afa17a50SWolfram Sang i = ~priv->tx_active & MSCAN_TXE;
200afa17a50SWolfram Sang buf_id = ffs(i) - 1;
201afa17a50SWolfram Sang switch (hweight8(i)) {
202afa17a50SWolfram Sang case 0:
203afa17a50SWolfram Sang netif_stop_queue(dev);
204aabdfd6aSWolfgang Grandegger netdev_err(dev, "Tx Ring full when queue awake!\n");
205afa17a50SWolfram Sang return NETDEV_TX_BUSY;
206afa17a50SWolfram Sang case 1:
207afa17a50SWolfram Sang /*
208afa17a50SWolfram Sang * if buf_id < 3, then current frame will be send out of order,
209afa17a50SWolfram Sang * since buffer with lower id have higher priority (hell..)
210afa17a50SWolfram Sang */
211afa17a50SWolfram Sang netif_stop_queue(dev);
21271ef9dfdSMarc Kleine-Budde fallthrough;
213afa17a50SWolfram Sang case 2:
214afa17a50SWolfram Sang if (buf_id < priv->prev_buf_id) {
215afa17a50SWolfram Sang priv->cur_pri++;
216afa17a50SWolfram Sang if (priv->cur_pri == 0xff) {
217afa17a50SWolfram Sang set_bit(F_TX_WAIT_ALL, &priv->flags);
218afa17a50SWolfram Sang netif_stop_queue(dev);
219afa17a50SWolfram Sang }
220afa17a50SWolfram Sang }
221afa17a50SWolfram Sang set_bit(F_TX_PROGRESS, &priv->flags);
222afa17a50SWolfram Sang break;
223afa17a50SWolfram Sang }
224afa17a50SWolfram Sang priv->prev_buf_id = buf_id;
225afa17a50SWolfram Sang out_8(®s->cantbsel, i);
226afa17a50SWolfram Sang
227afa17a50SWolfram Sang rtr = frame->can_id & CAN_RTR_FLAG;
228afa17a50SWolfram Sang
22974ff60b2SWolfram Sang /* RTR is always the lowest bit of interest, then IDs follow */
230afa17a50SWolfram Sang if (frame->can_id & CAN_EFF_FLAG) {
23174ff60b2SWolfram Sang can_id = (frame->can_id & CAN_EFF_MASK)
23274ff60b2SWolfram Sang << (MSCAN_EFF_RTR_SHIFT + 1);
233afa17a50SWolfram Sang if (rtr)
23474ff60b2SWolfram Sang can_id |= 1 << MSCAN_EFF_RTR_SHIFT;
235afa17a50SWolfram Sang out_be16(®s->tx.idr3_2, can_id);
236afa17a50SWolfram Sang
237afa17a50SWolfram Sang can_id >>= 16;
23825985edcSLucas De Marchi /* EFF_FLAGS are between the IDs :( */
23974ff60b2SWolfram Sang can_id = (can_id & 0x7) | ((can_id << 2) & 0xffe0)
24074ff60b2SWolfram Sang | MSCAN_EFF_FLAGS;
241afa17a50SWolfram Sang } else {
24274ff60b2SWolfram Sang can_id = (frame->can_id & CAN_SFF_MASK)
24374ff60b2SWolfram Sang << (MSCAN_SFF_RTR_SHIFT + 1);
244afa17a50SWolfram Sang if (rtr)
24574ff60b2SWolfram Sang can_id |= 1 << MSCAN_SFF_RTR_SHIFT;
246afa17a50SWolfram Sang }
247afa17a50SWolfram Sang out_be16(®s->tx.idr1_0, can_id);
248afa17a50SWolfram Sang
249afa17a50SWolfram Sang if (!rtr) {
250afa17a50SWolfram Sang void __iomem *data = ®s->tx.dsr1_0;
251afa17a50SWolfram Sang u16 *payload = (u16 *)frame->data;
2520285e7ceSWolfram Sang
253c7b74967SOliver Hartkopp for (i = 0; i < frame->len / 2; i++) {
254afa17a50SWolfram Sang out_be16(data, *payload++);
255afa17a50SWolfram Sang data += 2 + _MSCAN_RESERVED_DSR_SIZE;
256afa17a50SWolfram Sang }
257a3a4bfdeSWolfgang Grandegger /* write remaining byte if necessary */
258c7b74967SOliver Hartkopp if (frame->len & 1)
259c7b74967SOliver Hartkopp out_8(data, frame->data[frame->len - 1]);
260afa17a50SWolfram Sang }
261afa17a50SWolfram Sang
262c7b74967SOliver Hartkopp out_8(®s->tx.dlr, frame->len);
263afa17a50SWolfram Sang out_8(®s->tx.tbpr, priv->cur_pri);
264afa17a50SWolfram Sang
265afa17a50SWolfram Sang /* Start transmission. */
266afa17a50SWolfram Sang out_8(®s->cantflg, 1 << buf_id);
267afa17a50SWolfram Sang
268afa17a50SWolfram Sang if (!test_bit(F_TX_PROGRESS, &priv->flags))
269860e9538SFlorian Westphal netif_trans_update(dev);
270afa17a50SWolfram Sang
271afa17a50SWolfram Sang list_add_tail(&priv->tx_queue[buf_id].list, &priv->tx_head);
272afa17a50SWolfram Sang
2731dcb6e57SVincent Mailhol can_put_echo_skb(skb, dev, buf_id, 0);
274afa17a50SWolfram Sang
275afa17a50SWolfram Sang /* Enable interrupt. */
276afa17a50SWolfram Sang priv->tx_active |= 1 << buf_id;
277afa17a50SWolfram Sang out_8(®s->cantier, priv->tx_active);
278afa17a50SWolfram Sang
279afa17a50SWolfram Sang return NETDEV_TX_OK;
280afa17a50SWolfram Sang }
281afa17a50SWolfram Sang
get_new_state(struct net_device * dev,u8 canrflg)282b12a43e6SAndri Yngvason static enum can_state get_new_state(struct net_device *dev, u8 canrflg)
283afa17a50SWolfram Sang {
284afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev);
285afa17a50SWolfram Sang
286b12a43e6SAndri Yngvason if (unlikely(canrflg & MSCAN_CSCIF))
287b12a43e6SAndri Yngvason return state_map[max(MSCAN_STATE_RX(canrflg),
288afa17a50SWolfram Sang MSCAN_STATE_TX(canrflg))];
289b12a43e6SAndri Yngvason
290b12a43e6SAndri Yngvason return priv->can.state;
291afa17a50SWolfram Sang }
292afa17a50SWolfram Sang
mscan_get_rx_frame(struct net_device * dev,struct can_frame * frame)293afa17a50SWolfram Sang static void mscan_get_rx_frame(struct net_device *dev, struct can_frame *frame)
294afa17a50SWolfram Sang {
295afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev);
296665d7eb8SMarc Kleine-Budde struct mscan_regs __iomem *regs = priv->reg_base;
297afa17a50SWolfram Sang u32 can_id;
298afa17a50SWolfram Sang int i;
299afa17a50SWolfram Sang
300afa17a50SWolfram Sang can_id = in_be16(®s->rx.idr1_0);
301afa17a50SWolfram Sang if (can_id & (1 << 3)) {
302afa17a50SWolfram Sang frame->can_id = CAN_EFF_FLAG;
303afa17a50SWolfram Sang can_id = ((can_id << 16) | in_be16(®s->rx.idr3_2));
304afa17a50SWolfram Sang can_id = ((can_id & 0xffe00000) |
305afa17a50SWolfram Sang ((can_id & 0x7ffff) << 2)) >> 2;
306afa17a50SWolfram Sang } else {
307afa17a50SWolfram Sang can_id >>= 4;
308afa17a50SWolfram Sang frame->can_id = 0;
309afa17a50SWolfram Sang }
310afa17a50SWolfram Sang
311afa17a50SWolfram Sang frame->can_id |= can_id >> 1;
312afa17a50SWolfram Sang if (can_id & 1)
313afa17a50SWolfram Sang frame->can_id |= CAN_RTR_FLAG;
314c7cd606fSOliver Hartkopp
315c7b74967SOliver Hartkopp frame->len = can_cc_dlc2len(in_8(®s->rx.dlr) & 0xf);
316afa17a50SWolfram Sang
317afa17a50SWolfram Sang if (!(frame->can_id & CAN_RTR_FLAG)) {
318afa17a50SWolfram Sang void __iomem *data = ®s->rx.dsr1_0;
319afa17a50SWolfram Sang u16 *payload = (u16 *)frame->data;
3200285e7ceSWolfram Sang
321c7b74967SOliver Hartkopp for (i = 0; i < frame->len / 2; i++) {
322afa17a50SWolfram Sang *payload++ = in_be16(data);
323afa17a50SWolfram Sang data += 2 + _MSCAN_RESERVED_DSR_SIZE;
324afa17a50SWolfram Sang }
325a3a4bfdeSWolfgang Grandegger /* read remaining byte if necessary */
326c7b74967SOliver Hartkopp if (frame->len & 1)
327c7b74967SOliver Hartkopp frame->data[frame->len - 1] = in_8(data);
328afa17a50SWolfram Sang }
329afa17a50SWolfram Sang
330afa17a50SWolfram Sang out_8(®s->canrflg, MSCAN_RXF);
331afa17a50SWolfram Sang }
332afa17a50SWolfram Sang
mscan_get_err_frame(struct net_device * dev,struct can_frame * frame,u8 canrflg)333afa17a50SWolfram Sang static void mscan_get_err_frame(struct net_device *dev, struct can_frame *frame,
334afa17a50SWolfram Sang u8 canrflg)
335afa17a50SWolfram Sang {
336afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev);
337665d7eb8SMarc Kleine-Budde struct mscan_regs __iomem *regs = priv->reg_base;
338afa17a50SWolfram Sang struct net_device_stats *stats = &dev->stats;
339b12a43e6SAndri Yngvason enum can_state new_state;
340afa17a50SWolfram Sang
341aabdfd6aSWolfgang Grandegger netdev_dbg(dev, "error interrupt (canrflg=%#x)\n", canrflg);
342afa17a50SWolfram Sang frame->can_id = CAN_ERR_FLAG;
343afa17a50SWolfram Sang
344afa17a50SWolfram Sang if (canrflg & MSCAN_OVRIF) {
345afa17a50SWolfram Sang frame->can_id |= CAN_ERR_CRTL;
346afa17a50SWolfram Sang frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
347afa17a50SWolfram Sang stats->rx_over_errors++;
348afa17a50SWolfram Sang stats->rx_errors++;
3490285e7ceSWolfram Sang } else {
350afa17a50SWolfram Sang frame->data[1] = 0;
3510285e7ceSWolfram Sang }
352afa17a50SWolfram Sang
353b12a43e6SAndri Yngvason new_state = get_new_state(dev, canrflg);
354b12a43e6SAndri Yngvason if (new_state != priv->can.state) {
355b12a43e6SAndri Yngvason can_change_state(dev, frame,
356b12a43e6SAndri Yngvason state_map[MSCAN_STATE_TX(canrflg)],
357b12a43e6SAndri Yngvason state_map[MSCAN_STATE_RX(canrflg)]);
358b12a43e6SAndri Yngvason
359b12a43e6SAndri Yngvason if (priv->can.state == CAN_STATE_BUS_OFF) {
360afa17a50SWolfram Sang /*
361afa17a50SWolfram Sang * The MSCAN on the MPC5200 does recover from bus-off
362afa17a50SWolfram Sang * automatically. To avoid that we stop the chip doing
363afa17a50SWolfram Sang * a light-weight stop (we are in irq-context).
364afa17a50SWolfram Sang */
365bf3af547SWolfgang Grandegger if (priv->type != MSCAN_TYPE_MPC5121) {
366afa17a50SWolfram Sang out_8(®s->cantier, 0);
367afa17a50SWolfram Sang out_8(®s->canrier, 0);
368bf3af547SWolfgang Grandegger setbits8(®s->canctl0,
369bf3af547SWolfgang Grandegger MSCAN_SLPRQ | MSCAN_INITRQ);
370bf3af547SWolfgang Grandegger }
371afa17a50SWolfram Sang can_bus_off(dev);
372afa17a50SWolfram Sang }
373afa17a50SWolfram Sang }
374afa17a50SWolfram Sang priv->shadow_statflg = canrflg & MSCAN_STAT_MSK;
375c7b74967SOliver Hartkopp frame->len = CAN_ERR_DLC;
376afa17a50SWolfram Sang out_8(®s->canrflg, MSCAN_ERR_IF);
377afa17a50SWolfram Sang }
378afa17a50SWolfram Sang
mscan_rx_poll(struct napi_struct * napi,int quota)379afa17a50SWolfram Sang static int mscan_rx_poll(struct napi_struct *napi, int quota)
380afa17a50SWolfram Sang {
381afa17a50SWolfram Sang struct mscan_priv *priv = container_of(napi, struct mscan_priv, napi);
382afa17a50SWolfram Sang struct net_device *dev = napi->dev;
383665d7eb8SMarc Kleine-Budde struct mscan_regs __iomem *regs = priv->reg_base;
384afa17a50SWolfram Sang struct net_device_stats *stats = &dev->stats;
3852d77bd61SFlorian Faber int work_done = 0;
386afa17a50SWolfram Sang struct sk_buff *skb;
387afa17a50SWolfram Sang struct can_frame *frame;
388afa17a50SWolfram Sang u8 canrflg;
389afa17a50SWolfram Sang
3902d77bd61SFlorian Faber while (work_done < quota) {
39168bd7422SWolfram Sang canrflg = in_8(®s->canrflg);
39268bd7422SWolfram Sang if (!(canrflg & (MSCAN_RXF | MSCAN_ERR_IF)))
39368bd7422SWolfram Sang break;
394afa17a50SWolfram Sang
395afa17a50SWolfram Sang skb = alloc_can_skb(dev, &frame);
396afa17a50SWolfram Sang if (!skb) {
397afa17a50SWolfram Sang if (printk_ratelimit())
398aabdfd6aSWolfgang Grandegger netdev_notice(dev, "packet dropped\n");
399afa17a50SWolfram Sang stats->rx_dropped++;
400afa17a50SWolfram Sang out_8(®s->canrflg, canrflg);
401afa17a50SWolfram Sang continue;
402afa17a50SWolfram Sang }
403afa17a50SWolfram Sang
404676068dbSVincent Mailhol if (canrflg & MSCAN_RXF) {
405afa17a50SWolfram Sang mscan_get_rx_frame(dev, frame);
406afa17a50SWolfram Sang stats->rx_packets++;
4078e674ca7SVincent Mailhol if (!(frame->can_id & CAN_RTR_FLAG))
408c7b74967SOliver Hartkopp stats->rx_bytes += frame->len;
409676068dbSVincent Mailhol } else if (canrflg & MSCAN_ERR_IF) {
410676068dbSVincent Mailhol mscan_get_err_frame(dev, frame, canrflg);
411676068dbSVincent Mailhol }
412676068dbSVincent Mailhol
4132d77bd61SFlorian Faber work_done++;
414afa17a50SWolfram Sang netif_receive_skb(skb);
415afa17a50SWolfram Sang }
416afa17a50SWolfram Sang
4172d77bd61SFlorian Faber if (work_done < quota) {
4182d77bd61SFlorian Faber if (likely(napi_complete_done(&priv->napi, work_done))) {
419afa17a50SWolfram Sang clear_bit(F_RX_PROGRESS, &priv->flags);
420afa17a50SWolfram Sang if (priv->can.state < CAN_STATE_BUS_OFF)
421afa17a50SWolfram Sang out_8(®s->canrier, priv->shadow_canrier);
422afa17a50SWolfram Sang }
4232d77bd61SFlorian Faber }
4242d77bd61SFlorian Faber return work_done;
425afa17a50SWolfram Sang }
426afa17a50SWolfram Sang
mscan_isr(int irq,void * dev_id)427afa17a50SWolfram Sang static irqreturn_t mscan_isr(int irq, void *dev_id)
428afa17a50SWolfram Sang {
429afa17a50SWolfram Sang struct net_device *dev = (struct net_device *)dev_id;
430afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev);
431665d7eb8SMarc Kleine-Budde struct mscan_regs __iomem *regs = priv->reg_base;
432afa17a50SWolfram Sang struct net_device_stats *stats = &dev->stats;
433afa17a50SWolfram Sang u8 cantier, cantflg, canrflg;
434afa17a50SWolfram Sang irqreturn_t ret = IRQ_NONE;
435afa17a50SWolfram Sang
436afa17a50SWolfram Sang cantier = in_8(®s->cantier) & MSCAN_TXE;
437afa17a50SWolfram Sang cantflg = in_8(®s->cantflg) & cantier;
438afa17a50SWolfram Sang
439afa17a50SWolfram Sang if (cantier && cantflg) {
440afa17a50SWolfram Sang struct list_head *tmp, *pos;
441afa17a50SWolfram Sang
442afa17a50SWolfram Sang list_for_each_safe(pos, tmp, &priv->tx_head) {
443afa17a50SWolfram Sang struct tx_queue_entry *entry =
444afa17a50SWolfram Sang list_entry(pos, struct tx_queue_entry, list);
445afa17a50SWolfram Sang u8 mask = entry->mask;
446afa17a50SWolfram Sang
447afa17a50SWolfram Sang if (!(cantflg & mask))
448afa17a50SWolfram Sang continue;
449afa17a50SWolfram Sang
450afa17a50SWolfram Sang out_8(®s->cantbsel, mask);
451cc4b08c3SVincent Mailhol stats->tx_bytes += can_get_echo_skb(dev, entry->id,
452cc4b08c3SVincent Mailhol NULL);
453afa17a50SWolfram Sang stats->tx_packets++;
454afa17a50SWolfram Sang priv->tx_active &= ~mask;
455afa17a50SWolfram Sang list_del(pos);
456afa17a50SWolfram Sang }
457afa17a50SWolfram Sang
458afa17a50SWolfram Sang if (list_empty(&priv->tx_head)) {
459afa17a50SWolfram Sang clear_bit(F_TX_WAIT_ALL, &priv->flags);
460afa17a50SWolfram Sang clear_bit(F_TX_PROGRESS, &priv->flags);
461afa17a50SWolfram Sang priv->cur_pri = 0;
4620285e7ceSWolfram Sang } else {
463860e9538SFlorian Westphal netif_trans_update(dev);
4640285e7ceSWolfram Sang }
465afa17a50SWolfram Sang
466afa17a50SWolfram Sang if (!test_bit(F_TX_WAIT_ALL, &priv->flags))
467afa17a50SWolfram Sang netif_wake_queue(dev);
468afa17a50SWolfram Sang
469afa17a50SWolfram Sang out_8(®s->cantier, priv->tx_active);
470afa17a50SWolfram Sang ret = IRQ_HANDLED;
471afa17a50SWolfram Sang }
472afa17a50SWolfram Sang
473afa17a50SWolfram Sang canrflg = in_8(®s->canrflg);
474afa17a50SWolfram Sang if ((canrflg & ~MSCAN_STAT_MSK) &&
475afa17a50SWolfram Sang !test_and_set_bit(F_RX_PROGRESS, &priv->flags)) {
476afa17a50SWolfram Sang if (canrflg & ~MSCAN_STAT_MSK) {
477afa17a50SWolfram Sang priv->shadow_canrier = in_8(®s->canrier);
478afa17a50SWolfram Sang out_8(®s->canrier, 0);
479afa17a50SWolfram Sang napi_schedule(&priv->napi);
480afa17a50SWolfram Sang ret = IRQ_HANDLED;
4810285e7ceSWolfram Sang } else {
482afa17a50SWolfram Sang clear_bit(F_RX_PROGRESS, &priv->flags);
483afa17a50SWolfram Sang }
4840285e7ceSWolfram Sang }
485afa17a50SWolfram Sang return ret;
486afa17a50SWolfram Sang }
487afa17a50SWolfram Sang
mscan_do_set_mode(struct net_device * dev,enum can_mode mode)488afa17a50SWolfram Sang static int mscan_do_set_mode(struct net_device *dev, enum can_mode mode)
489afa17a50SWolfram Sang {
490afa17a50SWolfram Sang int ret = 0;
491afa17a50SWolfram Sang
492afa17a50SWolfram Sang switch (mode) {
493afa17a50SWolfram Sang case CAN_MODE_START:
494bf3af547SWolfgang Grandegger ret = mscan_restart(dev);
495afa17a50SWolfram Sang if (ret)
496afa17a50SWolfram Sang break;
497afa17a50SWolfram Sang if (netif_queue_stopped(dev))
498afa17a50SWolfram Sang netif_wake_queue(dev);
499afa17a50SWolfram Sang break;
500afa17a50SWolfram Sang
501afa17a50SWolfram Sang default:
502afa17a50SWolfram Sang ret = -EOPNOTSUPP;
503afa17a50SWolfram Sang break;
504afa17a50SWolfram Sang }
505afa17a50SWolfram Sang return ret;
506afa17a50SWolfram Sang }
507afa17a50SWolfram Sang
mscan_do_set_bittiming(struct net_device * dev)508afa17a50SWolfram Sang static int mscan_do_set_bittiming(struct net_device *dev)
509afa17a50SWolfram Sang {
510afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev);
511665d7eb8SMarc Kleine-Budde struct mscan_regs __iomem *regs = priv->reg_base;
512afa17a50SWolfram Sang struct can_bittiming *bt = &priv->can.bittiming;
513afa17a50SWolfram Sang u8 btr0, btr1;
514afa17a50SWolfram Sang
515afa17a50SWolfram Sang btr0 = BTR0_SET_BRP(bt->brp) | BTR0_SET_SJW(bt->sjw);
516afa17a50SWolfram Sang btr1 = (BTR1_SET_TSEG1(bt->prop_seg + bt->phase_seg1) |
517afa17a50SWolfram Sang BTR1_SET_TSEG2(bt->phase_seg2) |
518afa17a50SWolfram Sang BTR1_SET_SAM(priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES));
519afa17a50SWolfram Sang
520aabdfd6aSWolfgang Grandegger netdev_info(dev, "setting BTR0=0x%02x BTR1=0x%02x\n", btr0, btr1);
521afa17a50SWolfram Sang
522afa17a50SWolfram Sang out_8(®s->canbtr0, btr0);
523afa17a50SWolfram Sang out_8(®s->canbtr1, btr1);
524afa17a50SWolfram Sang
525afa17a50SWolfram Sang return 0;
526afa17a50SWolfram Sang }
527afa17a50SWolfram Sang
mscan_get_berr_counter(const struct net_device * dev,struct can_berr_counter * bec)52879d0d8a7SWolfgang Grandegger static int mscan_get_berr_counter(const struct net_device *dev,
52979d0d8a7SWolfgang Grandegger struct can_berr_counter *bec)
53079d0d8a7SWolfgang Grandegger {
53179d0d8a7SWolfgang Grandegger struct mscan_priv *priv = netdev_priv(dev);
53279d0d8a7SWolfgang Grandegger struct mscan_regs __iomem *regs = priv->reg_base;
53379d0d8a7SWolfgang Grandegger
53479d0d8a7SWolfgang Grandegger bec->txerr = in_8(®s->cantxerr);
53579d0d8a7SWolfgang Grandegger bec->rxerr = in_8(®s->canrxerr);
53679d0d8a7SWolfgang Grandegger
53779d0d8a7SWolfgang Grandegger return 0;
53879d0d8a7SWolfgang Grandegger }
53979d0d8a7SWolfgang Grandegger
mscan_open(struct net_device * dev)540afa17a50SWolfram Sang static int mscan_open(struct net_device *dev)
541afa17a50SWolfram Sang {
542afa17a50SWolfram Sang int ret;
543afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev);
544665d7eb8SMarc Kleine-Budde struct mscan_regs __iomem *regs = priv->reg_base;
545afa17a50SWolfram Sang
5461149108eSGerhard Sittig ret = clk_prepare_enable(priv->clk_ipg);
5471149108eSGerhard Sittig if (ret)
5481149108eSGerhard Sittig goto exit_retcode;
5491149108eSGerhard Sittig ret = clk_prepare_enable(priv->clk_can);
5501149108eSGerhard Sittig if (ret)
5511149108eSGerhard Sittig goto exit_dis_ipg_clock;
5521149108eSGerhard Sittig
553afa17a50SWolfram Sang /* common open */
554afa17a50SWolfram Sang ret = open_candev(dev);
555afa17a50SWolfram Sang if (ret)
5561149108eSGerhard Sittig goto exit_dis_can_clock;
557afa17a50SWolfram Sang
558afa17a50SWolfram Sang napi_enable(&priv->napi);
559afa17a50SWolfram Sang
560afa17a50SWolfram Sang ret = request_irq(dev->irq, mscan_isr, 0, dev->name, dev);
561afa17a50SWolfram Sang if (ret < 0) {
562aabdfd6aSWolfgang Grandegger netdev_err(dev, "failed to attach interrupt\n");
563323907acSWolfram Sang goto exit_napi_disable;
564afa17a50SWolfram Sang }
565afa17a50SWolfram Sang
566abbd00b8SWolfgang Grandegger if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
567452448f9SMarc Kleine-Budde setbits8(®s->canctl1, MSCAN_LISTEN);
568452448f9SMarc Kleine-Budde else
56959179ea6SWolfram Sang clrbits8(®s->canctl1, MSCAN_LISTEN);
570afa17a50SWolfram Sang
571afa17a50SWolfram Sang ret = mscan_start(dev);
572afa17a50SWolfram Sang if (ret)
573323907acSWolfram Sang goto exit_free_irq;
574afa17a50SWolfram Sang
575afa17a50SWolfram Sang netif_start_queue(dev);
576afa17a50SWolfram Sang
577afa17a50SWolfram Sang return 0;
578323907acSWolfram Sang
579323907acSWolfram Sang exit_free_irq:
580323907acSWolfram Sang free_irq(dev->irq, dev);
581323907acSWolfram Sang exit_napi_disable:
582323907acSWolfram Sang napi_disable(&priv->napi);
583323907acSWolfram Sang close_candev(dev);
5841149108eSGerhard Sittig exit_dis_can_clock:
5851149108eSGerhard Sittig clk_disable_unprepare(priv->clk_can);
5861149108eSGerhard Sittig exit_dis_ipg_clock:
5871149108eSGerhard Sittig clk_disable_unprepare(priv->clk_ipg);
5881149108eSGerhard Sittig exit_retcode:
589323907acSWolfram Sang return ret;
590afa17a50SWolfram Sang }
591afa17a50SWolfram Sang
mscan_close(struct net_device * dev)592afa17a50SWolfram Sang static int mscan_close(struct net_device *dev)
593afa17a50SWolfram Sang {
594afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev);
595665d7eb8SMarc Kleine-Budde struct mscan_regs __iomem *regs = priv->reg_base;
596afa17a50SWolfram Sang
597afa17a50SWolfram Sang netif_stop_queue(dev);
598afa17a50SWolfram Sang napi_disable(&priv->napi);
599afa17a50SWolfram Sang
600afa17a50SWolfram Sang out_8(®s->cantier, 0);
601afa17a50SWolfram Sang out_8(®s->canrier, 0);
602afa17a50SWolfram Sang mscan_set_mode(dev, MSCAN_INIT_MODE);
603afa17a50SWolfram Sang close_candev(dev);
604afa17a50SWolfram Sang free_irq(dev->irq, dev);
605afa17a50SWolfram Sang
6061149108eSGerhard Sittig clk_disable_unprepare(priv->clk_can);
6071149108eSGerhard Sittig clk_disable_unprepare(priv->clk_ipg);
6081149108eSGerhard Sittig
609afa17a50SWolfram Sang return 0;
610afa17a50SWolfram Sang }
611afa17a50SWolfram Sang
612afa17a50SWolfram Sang static const struct net_device_ops mscan_netdev_ops = {
613afa17a50SWolfram Sang .ndo_open = mscan_open,
614afa17a50SWolfram Sang .ndo_stop = mscan_close,
615afa17a50SWolfram Sang .ndo_start_xmit = mscan_start_xmit,
616c971fa2aSOliver Hartkopp .ndo_change_mtu = can_change_mtu,
617afa17a50SWolfram Sang };
618afa17a50SWolfram Sang
619409c188cSVincent Mailhol static const struct ethtool_ops mscan_ethtool_ops = {
620409c188cSVincent Mailhol .get_ts_info = ethtool_op_get_ts_info,
621409c188cSVincent Mailhol };
622409c188cSVincent Mailhol
register_mscandev(struct net_device * dev,int mscan_clksrc)623bf3af547SWolfgang Grandegger int register_mscandev(struct net_device *dev, int mscan_clksrc)
624afa17a50SWolfram Sang {
625afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev);
626665d7eb8SMarc Kleine-Budde struct mscan_regs __iomem *regs = priv->reg_base;
627afa17a50SWolfram Sang u8 ctl1;
628afa17a50SWolfram Sang
629afa17a50SWolfram Sang ctl1 = in_8(®s->canctl1);
630bf3af547SWolfgang Grandegger if (mscan_clksrc)
631afa17a50SWolfram Sang ctl1 |= MSCAN_CLKSRC;
632afa17a50SWolfram Sang else
633afa17a50SWolfram Sang ctl1 &= ~MSCAN_CLKSRC;
634afa17a50SWolfram Sang
63579d0d8a7SWolfgang Grandegger if (priv->type == MSCAN_TYPE_MPC5121) {
63679d0d8a7SWolfgang Grandegger priv->can.do_get_berr_counter = mscan_get_berr_counter;
637bf3af547SWolfgang Grandegger ctl1 |= MSCAN_BORM; /* bus-off recovery upon request */
63879d0d8a7SWolfgang Grandegger }
639bf3af547SWolfgang Grandegger
640afa17a50SWolfram Sang ctl1 |= MSCAN_CANE;
641afa17a50SWolfram Sang out_8(®s->canctl1, ctl1);
642afa17a50SWolfram Sang udelay(100);
643afa17a50SWolfram Sang
644afa17a50SWolfram Sang /* acceptance mask/acceptance code (accept everything) */
645afa17a50SWolfram Sang out_be16(®s->canidar1_0, 0);
646afa17a50SWolfram Sang out_be16(®s->canidar3_2, 0);
647afa17a50SWolfram Sang out_be16(®s->canidar5_4, 0);
648afa17a50SWolfram Sang out_be16(®s->canidar7_6, 0);
649afa17a50SWolfram Sang
650afa17a50SWolfram Sang out_be16(®s->canidmr1_0, 0xffff);
651afa17a50SWolfram Sang out_be16(®s->canidmr3_2, 0xffff);
652afa17a50SWolfram Sang out_be16(®s->canidmr5_4, 0xffff);
653afa17a50SWolfram Sang out_be16(®s->canidmr7_6, 0xffff);
654afa17a50SWolfram Sang /* Two 32 bit Acceptance Filters */
655afa17a50SWolfram Sang out_8(®s->canidac, MSCAN_AF_32BIT);
656afa17a50SWolfram Sang
657afa17a50SWolfram Sang mscan_set_mode(dev, MSCAN_INIT_MODE);
658afa17a50SWolfram Sang
659afa17a50SWolfram Sang return register_candev(dev);
660afa17a50SWolfram Sang }
661afa17a50SWolfram Sang
unregister_mscandev(struct net_device * dev)662afa17a50SWolfram Sang void unregister_mscandev(struct net_device *dev)
663afa17a50SWolfram Sang {
664afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev);
665665d7eb8SMarc Kleine-Budde struct mscan_regs __iomem *regs = priv->reg_base;
666afa17a50SWolfram Sang mscan_set_mode(dev, MSCAN_INIT_MODE);
66759179ea6SWolfram Sang clrbits8(®s->canctl1, MSCAN_CANE);
668afa17a50SWolfram Sang unregister_candev(dev);
669afa17a50SWolfram Sang }
670afa17a50SWolfram Sang
alloc_mscandev(void)671afa17a50SWolfram Sang struct net_device *alloc_mscandev(void)
672afa17a50SWolfram Sang {
673afa17a50SWolfram Sang struct net_device *dev;
674afa17a50SWolfram Sang struct mscan_priv *priv;
675afa17a50SWolfram Sang int i;
676afa17a50SWolfram Sang
677afa17a50SWolfram Sang dev = alloc_candev(sizeof(struct mscan_priv), MSCAN_ECHO_SKB_MAX);
678afa17a50SWolfram Sang if (!dev)
679afa17a50SWolfram Sang return NULL;
680afa17a50SWolfram Sang priv = netdev_priv(dev);
681afa17a50SWolfram Sang
682afa17a50SWolfram Sang dev->netdev_ops = &mscan_netdev_ops;
683409c188cSVincent Mailhol dev->ethtool_ops = &mscan_ethtool_ops;
684afa17a50SWolfram Sang
685afa17a50SWolfram Sang dev->flags |= IFF_ECHO; /* we support local echo */
686afa17a50SWolfram Sang
687caf6b7f8SJakub Kicinski netif_napi_add_weight(dev, &priv->napi, mscan_rx_poll, 8);
688afa17a50SWolfram Sang
689afa17a50SWolfram Sang priv->can.bittiming_const = &mscan_bittiming_const;
690afa17a50SWolfram Sang priv->can.do_set_bittiming = mscan_do_set_bittiming;
691afa17a50SWolfram Sang priv->can.do_set_mode = mscan_do_set_mode;
692452448f9SMarc Kleine-Budde priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES |
693452448f9SMarc Kleine-Budde CAN_CTRLMODE_LISTENONLY;
694afa17a50SWolfram Sang
695afa17a50SWolfram Sang for (i = 0; i < TX_QUEUE_SIZE; i++) {
696afa17a50SWolfram Sang priv->tx_queue[i].id = i;
697afa17a50SWolfram Sang priv->tx_queue[i].mask = 1 << i;
698afa17a50SWolfram Sang }
699afa17a50SWolfram Sang
700afa17a50SWolfram Sang return dev;
701afa17a50SWolfram Sang }
702afa17a50SWolfram Sang
703afa17a50SWolfram Sang MODULE_AUTHOR("Andrey Volkov <avolkov@varma-el.com>");
704afa17a50SWolfram Sang MODULE_LICENSE("GPL v2");
705afa17a50SWolfram Sang MODULE_DESCRIPTION("CAN port driver for a MSCAN based chips");
706