1afa17a50SWolfram Sang /* 2afa17a50SWolfram Sang * CAN bus driver for the alone generic (as possible as) MSCAN controller. 3afa17a50SWolfram Sang * 4afa17a50SWolfram Sang * Copyright (C) 2005-2006 Andrey Volkov <avolkov@varma-el.com>, 5afa17a50SWolfram Sang * Varma Electronics Oy 6afa17a50SWolfram Sang * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com> 7afa17a50SWolfram Sang * Copytight (C) 2008-2009 Pengutronix <kernel@pengutronix.de> 8afa17a50SWolfram Sang * 9afa17a50SWolfram Sang * This program is free software; you can redistribute it and/or modify 10afa17a50SWolfram Sang * it under the terms of the version 2 of the GNU General Public License 11afa17a50SWolfram Sang * as published by the Free Software Foundation 12afa17a50SWolfram Sang * 13afa17a50SWolfram Sang * This program is distributed in the hope that it will be useful, 14afa17a50SWolfram Sang * but WITHOUT ANY WARRANTY; without even the implied warranty of 15afa17a50SWolfram Sang * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16afa17a50SWolfram Sang * GNU General Public License for more details. 17afa17a50SWolfram Sang * 18afa17a50SWolfram Sang * You should have received a copy of the GNU General Public License 19afa17a50SWolfram Sang * along with this program; if not, write to the Free Software 20afa17a50SWolfram Sang * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 21afa17a50SWolfram Sang */ 22afa17a50SWolfram Sang 23afa17a50SWolfram Sang #include <linux/kernel.h> 24afa17a50SWolfram Sang #include <linux/module.h> 25afa17a50SWolfram Sang #include <linux/interrupt.h> 26afa17a50SWolfram Sang #include <linux/delay.h> 27afa17a50SWolfram Sang #include <linux/netdevice.h> 28afa17a50SWolfram Sang #include <linux/if_arp.h> 29afa17a50SWolfram Sang #include <linux/if_ether.h> 30afa17a50SWolfram Sang #include <linux/list.h> 31afa17a50SWolfram Sang #include <linux/can.h> 32afa17a50SWolfram Sang #include <linux/can/dev.h> 33afa17a50SWolfram Sang #include <linux/can/error.h> 34afa17a50SWolfram Sang #include <linux/io.h> 35afa17a50SWolfram Sang 36afa17a50SWolfram Sang #include "mscan.h" 37afa17a50SWolfram Sang 38afa17a50SWolfram Sang static struct can_bittiming_const mscan_bittiming_const = { 39afa17a50SWolfram Sang .name = "mscan", 40afa17a50SWolfram Sang .tseg1_min = 4, 41afa17a50SWolfram Sang .tseg1_max = 16, 42afa17a50SWolfram Sang .tseg2_min = 2, 43afa17a50SWolfram Sang .tseg2_max = 8, 44afa17a50SWolfram Sang .sjw_max = 4, 45afa17a50SWolfram Sang .brp_min = 1, 46afa17a50SWolfram Sang .brp_max = 64, 47afa17a50SWolfram Sang .brp_inc = 1, 48afa17a50SWolfram Sang }; 49afa17a50SWolfram Sang 50afa17a50SWolfram Sang struct mscan_state { 51afa17a50SWolfram Sang u8 mode; 52afa17a50SWolfram Sang u8 canrier; 53afa17a50SWolfram Sang u8 cantier; 54afa17a50SWolfram Sang }; 55afa17a50SWolfram Sang 56afa17a50SWolfram Sang static enum can_state state_map[] = { 57afa17a50SWolfram Sang CAN_STATE_ERROR_ACTIVE, 58afa17a50SWolfram Sang CAN_STATE_ERROR_WARNING, 59afa17a50SWolfram Sang CAN_STATE_ERROR_PASSIVE, 60afa17a50SWolfram Sang CAN_STATE_BUS_OFF 61afa17a50SWolfram Sang }; 62afa17a50SWolfram Sang 63afa17a50SWolfram Sang static int mscan_set_mode(struct net_device *dev, u8 mode) 64afa17a50SWolfram Sang { 65afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev); 66afa17a50SWolfram Sang struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; 67afa17a50SWolfram Sang int ret = 0; 68afa17a50SWolfram Sang int i; 69afa17a50SWolfram Sang u8 canctl1; 70afa17a50SWolfram Sang 71afa17a50SWolfram Sang if (mode != MSCAN_NORMAL_MODE) { 72afa17a50SWolfram Sang if (priv->tx_active) { 73afa17a50SWolfram Sang /* Abort transfers before going to sleep */# 74afa17a50SWolfram Sang out_8(®s->cantarq, priv->tx_active); 75afa17a50SWolfram Sang /* Suppress TX done interrupts */ 76afa17a50SWolfram Sang out_8(®s->cantier, 0); 77afa17a50SWolfram Sang } 78afa17a50SWolfram Sang 79afa17a50SWolfram Sang canctl1 = in_8(®s->canctl1); 800285e7ceSWolfram Sang if ((mode & MSCAN_SLPRQ) && !(canctl1 & MSCAN_SLPAK)) { 8159179ea6SWolfram Sang setbits8(®s->canctl0, MSCAN_SLPRQ); 82afa17a50SWolfram Sang for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) { 83afa17a50SWolfram Sang if (in_8(®s->canctl1) & MSCAN_SLPAK) 84afa17a50SWolfram Sang break; 85afa17a50SWolfram Sang udelay(100); 86afa17a50SWolfram Sang } 87afa17a50SWolfram Sang /* 88afa17a50SWolfram Sang * The mscan controller will fail to enter sleep mode, 89afa17a50SWolfram Sang * while there are irregular activities on bus, like 90afa17a50SWolfram Sang * somebody keeps retransmitting. This behavior is 91afa17a50SWolfram Sang * undocumented and seems to differ between mscan built 92afa17a50SWolfram Sang * in mpc5200b and mpc5200. We proceed in that case, 93afa17a50SWolfram Sang * since otherwise the slprq will be kept set and the 94afa17a50SWolfram Sang * controller will get stuck. NOTE: INITRQ or CSWAI 95afa17a50SWolfram Sang * will abort all active transmit actions, if still 96afa17a50SWolfram Sang * any, at once. 97afa17a50SWolfram Sang */ 98afa17a50SWolfram Sang if (i >= MSCAN_SET_MODE_RETRIES) 99afa17a50SWolfram Sang dev_dbg(dev->dev.parent, 100afa17a50SWolfram Sang "device failed to enter sleep mode. " 101afa17a50SWolfram Sang "We proceed anyhow.\n"); 102afa17a50SWolfram Sang else 103afa17a50SWolfram Sang priv->can.state = CAN_STATE_SLEEPING; 104afa17a50SWolfram Sang } 105afa17a50SWolfram Sang 1060285e7ceSWolfram Sang if ((mode & MSCAN_INITRQ) && !(canctl1 & MSCAN_INITAK)) { 10759179ea6SWolfram Sang setbits8(®s->canctl0, MSCAN_INITRQ); 108afa17a50SWolfram Sang for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) { 109afa17a50SWolfram Sang if (in_8(®s->canctl1) & MSCAN_INITAK) 110afa17a50SWolfram Sang break; 111afa17a50SWolfram Sang } 112afa17a50SWolfram Sang if (i >= MSCAN_SET_MODE_RETRIES) 113afa17a50SWolfram Sang ret = -ENODEV; 114afa17a50SWolfram Sang } 115afa17a50SWolfram Sang if (!ret) 116afa17a50SWolfram Sang priv->can.state = CAN_STATE_STOPPED; 117afa17a50SWolfram Sang 118afa17a50SWolfram Sang if (mode & MSCAN_CSWAI) 11959179ea6SWolfram Sang setbits8(®s->canctl0, MSCAN_CSWAI); 120afa17a50SWolfram Sang 121afa17a50SWolfram Sang } else { 122afa17a50SWolfram Sang canctl1 = in_8(®s->canctl1); 123afa17a50SWolfram Sang if (canctl1 & (MSCAN_SLPAK | MSCAN_INITAK)) { 12459179ea6SWolfram Sang clrbits8(®s->canctl0, MSCAN_SLPRQ | MSCAN_INITRQ); 125afa17a50SWolfram Sang for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) { 126afa17a50SWolfram Sang canctl1 = in_8(®s->canctl1); 127afa17a50SWolfram Sang if (!(canctl1 & (MSCAN_INITAK | MSCAN_SLPAK))) 128afa17a50SWolfram Sang break; 129afa17a50SWolfram Sang } 130afa17a50SWolfram Sang if (i >= MSCAN_SET_MODE_RETRIES) 131afa17a50SWolfram Sang ret = -ENODEV; 132afa17a50SWolfram Sang else 133afa17a50SWolfram Sang priv->can.state = CAN_STATE_ERROR_ACTIVE; 134afa17a50SWolfram Sang } 135afa17a50SWolfram Sang } 136afa17a50SWolfram Sang return ret; 137afa17a50SWolfram Sang } 138afa17a50SWolfram Sang 139afa17a50SWolfram Sang static int mscan_start(struct net_device *dev) 140afa17a50SWolfram Sang { 141afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev); 142afa17a50SWolfram Sang struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; 143afa17a50SWolfram Sang u8 canrflg; 144afa17a50SWolfram Sang int err; 145afa17a50SWolfram Sang 146afa17a50SWolfram Sang out_8(®s->canrier, 0); 147afa17a50SWolfram Sang 148afa17a50SWolfram Sang INIT_LIST_HEAD(&priv->tx_head); 149afa17a50SWolfram Sang priv->prev_buf_id = 0; 150afa17a50SWolfram Sang priv->cur_pri = 0; 151afa17a50SWolfram Sang priv->tx_active = 0; 152afa17a50SWolfram Sang priv->shadow_canrier = 0; 153afa17a50SWolfram Sang priv->flags = 0; 154afa17a50SWolfram Sang 155afa17a50SWolfram Sang err = mscan_set_mode(dev, MSCAN_NORMAL_MODE); 156afa17a50SWolfram Sang if (err) 157afa17a50SWolfram Sang return err; 158afa17a50SWolfram Sang 159afa17a50SWolfram Sang canrflg = in_8(®s->canrflg); 160afa17a50SWolfram Sang priv->shadow_statflg = canrflg & MSCAN_STAT_MSK; 161afa17a50SWolfram Sang priv->can.state = state_map[max(MSCAN_STATE_RX(canrflg), 162afa17a50SWolfram Sang MSCAN_STATE_TX(canrflg))]; 163afa17a50SWolfram Sang out_8(®s->cantier, 0); 164afa17a50SWolfram Sang 165afa17a50SWolfram Sang /* Enable receive interrupts. */ 166afa17a50SWolfram Sang out_8(®s->canrier, MSCAN_OVRIE | MSCAN_RXFIE | MSCAN_CSCIE | 167afa17a50SWolfram Sang MSCAN_RSTATE1 | MSCAN_RSTATE0 | MSCAN_TSTATE1 | MSCAN_TSTATE0); 168afa17a50SWolfram Sang 169afa17a50SWolfram Sang return 0; 170afa17a50SWolfram Sang } 171afa17a50SWolfram Sang 172afa17a50SWolfram Sang static netdev_tx_t mscan_start_xmit(struct sk_buff *skb, struct net_device *dev) 173afa17a50SWolfram Sang { 174afa17a50SWolfram Sang struct can_frame *frame = (struct can_frame *)skb->data; 175afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev); 176afa17a50SWolfram Sang struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; 177afa17a50SWolfram Sang int i, rtr, buf_id; 178afa17a50SWolfram Sang u32 can_id; 179afa17a50SWolfram Sang 180afa17a50SWolfram Sang if (frame->can_dlc > 8) 181afa17a50SWolfram Sang return -EINVAL; 182afa17a50SWolfram Sang 183afa17a50SWolfram Sang out_8(®s->cantier, 0); 184afa17a50SWolfram Sang 185afa17a50SWolfram Sang i = ~priv->tx_active & MSCAN_TXE; 186afa17a50SWolfram Sang buf_id = ffs(i) - 1; 187afa17a50SWolfram Sang switch (hweight8(i)) { 188afa17a50SWolfram Sang case 0: 189afa17a50SWolfram Sang netif_stop_queue(dev); 190afa17a50SWolfram Sang dev_err(dev->dev.parent, "Tx Ring full when queue awake!\n"); 191afa17a50SWolfram Sang return NETDEV_TX_BUSY; 192afa17a50SWolfram Sang case 1: 193afa17a50SWolfram Sang /* 194afa17a50SWolfram Sang * if buf_id < 3, then current frame will be send out of order, 195afa17a50SWolfram Sang * since buffer with lower id have higher priority (hell..) 196afa17a50SWolfram Sang */ 197afa17a50SWolfram Sang netif_stop_queue(dev); 198afa17a50SWolfram Sang case 2: 199afa17a50SWolfram Sang if (buf_id < priv->prev_buf_id) { 200afa17a50SWolfram Sang priv->cur_pri++; 201afa17a50SWolfram Sang if (priv->cur_pri == 0xff) { 202afa17a50SWolfram Sang set_bit(F_TX_WAIT_ALL, &priv->flags); 203afa17a50SWolfram Sang netif_stop_queue(dev); 204afa17a50SWolfram Sang } 205afa17a50SWolfram Sang } 206afa17a50SWolfram Sang set_bit(F_TX_PROGRESS, &priv->flags); 207afa17a50SWolfram Sang break; 208afa17a50SWolfram Sang } 209afa17a50SWolfram Sang priv->prev_buf_id = buf_id; 210afa17a50SWolfram Sang out_8(®s->cantbsel, i); 211afa17a50SWolfram Sang 212afa17a50SWolfram Sang rtr = frame->can_id & CAN_RTR_FLAG; 213afa17a50SWolfram Sang 21474ff60b2SWolfram Sang /* RTR is always the lowest bit of interest, then IDs follow */ 215afa17a50SWolfram Sang if (frame->can_id & CAN_EFF_FLAG) { 21674ff60b2SWolfram Sang can_id = (frame->can_id & CAN_EFF_MASK) 21774ff60b2SWolfram Sang << (MSCAN_EFF_RTR_SHIFT + 1); 218afa17a50SWolfram Sang if (rtr) 21974ff60b2SWolfram Sang can_id |= 1 << MSCAN_EFF_RTR_SHIFT; 220afa17a50SWolfram Sang out_be16(®s->tx.idr3_2, can_id); 221afa17a50SWolfram Sang 222afa17a50SWolfram Sang can_id >>= 16; 22374ff60b2SWolfram Sang /* EFF_FLAGS are inbetween the IDs :( */ 22474ff60b2SWolfram Sang can_id = (can_id & 0x7) | ((can_id << 2) & 0xffe0) 22574ff60b2SWolfram Sang | MSCAN_EFF_FLAGS; 226afa17a50SWolfram Sang } else { 22774ff60b2SWolfram Sang can_id = (frame->can_id & CAN_SFF_MASK) 22874ff60b2SWolfram Sang << (MSCAN_SFF_RTR_SHIFT + 1); 229afa17a50SWolfram Sang if (rtr) 23074ff60b2SWolfram Sang can_id |= 1 << MSCAN_SFF_RTR_SHIFT; 231afa17a50SWolfram Sang } 232afa17a50SWolfram Sang out_be16(®s->tx.idr1_0, can_id); 233afa17a50SWolfram Sang 234afa17a50SWolfram Sang if (!rtr) { 235afa17a50SWolfram Sang void __iomem *data = ®s->tx.dsr1_0; 236afa17a50SWolfram Sang u16 *payload = (u16 *)frame->data; 2370285e7ceSWolfram Sang 238afa17a50SWolfram Sang /* It is safe to write into dsr[dlc+1] */ 239afa17a50SWolfram Sang for (i = 0; i < (frame->can_dlc + 1) / 2; i++) { 240afa17a50SWolfram Sang out_be16(data, *payload++); 241afa17a50SWolfram Sang data += 2 + _MSCAN_RESERVED_DSR_SIZE; 242afa17a50SWolfram Sang } 243afa17a50SWolfram Sang } 244afa17a50SWolfram Sang 245afa17a50SWolfram Sang out_8(®s->tx.dlr, frame->can_dlc); 246afa17a50SWolfram Sang out_8(®s->tx.tbpr, priv->cur_pri); 247afa17a50SWolfram Sang 248afa17a50SWolfram Sang /* Start transmission. */ 249afa17a50SWolfram Sang out_8(®s->cantflg, 1 << buf_id); 250afa17a50SWolfram Sang 251afa17a50SWolfram Sang if (!test_bit(F_TX_PROGRESS, &priv->flags)) 252afa17a50SWolfram Sang dev->trans_start = jiffies; 253afa17a50SWolfram Sang 254afa17a50SWolfram Sang list_add_tail(&priv->tx_queue[buf_id].list, &priv->tx_head); 255afa17a50SWolfram Sang 256afa17a50SWolfram Sang can_put_echo_skb(skb, dev, buf_id); 257afa17a50SWolfram Sang 258afa17a50SWolfram Sang /* Enable interrupt. */ 259afa17a50SWolfram Sang priv->tx_active |= 1 << buf_id; 260afa17a50SWolfram Sang out_8(®s->cantier, priv->tx_active); 261afa17a50SWolfram Sang 262afa17a50SWolfram Sang return NETDEV_TX_OK; 263afa17a50SWolfram Sang } 264afa17a50SWolfram Sang 265afa17a50SWolfram Sang /* This function returns the old state to see where we came from */ 266afa17a50SWolfram Sang static enum can_state check_set_state(struct net_device *dev, u8 canrflg) 267afa17a50SWolfram Sang { 268afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev); 269afa17a50SWolfram Sang enum can_state state, old_state = priv->can.state; 270afa17a50SWolfram Sang 271afa17a50SWolfram Sang if (canrflg & MSCAN_CSCIF && old_state <= CAN_STATE_BUS_OFF) { 272afa17a50SWolfram Sang state = state_map[max(MSCAN_STATE_RX(canrflg), 273afa17a50SWolfram Sang MSCAN_STATE_TX(canrflg))]; 274afa17a50SWolfram Sang priv->can.state = state; 275afa17a50SWolfram Sang } 276afa17a50SWolfram Sang return old_state; 277afa17a50SWolfram Sang } 278afa17a50SWolfram Sang 279afa17a50SWolfram Sang static void mscan_get_rx_frame(struct net_device *dev, struct can_frame *frame) 280afa17a50SWolfram Sang { 281afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev); 282afa17a50SWolfram Sang struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; 283afa17a50SWolfram Sang u32 can_id; 284afa17a50SWolfram Sang int i; 285afa17a50SWolfram Sang 286afa17a50SWolfram Sang can_id = in_be16(®s->rx.idr1_0); 287afa17a50SWolfram Sang if (can_id & (1 << 3)) { 288afa17a50SWolfram Sang frame->can_id = CAN_EFF_FLAG; 289afa17a50SWolfram Sang can_id = ((can_id << 16) | in_be16(®s->rx.idr3_2)); 290afa17a50SWolfram Sang can_id = ((can_id & 0xffe00000) | 291afa17a50SWolfram Sang ((can_id & 0x7ffff) << 2)) >> 2; 292afa17a50SWolfram Sang } else { 293afa17a50SWolfram Sang can_id >>= 4; 294afa17a50SWolfram Sang frame->can_id = 0; 295afa17a50SWolfram Sang } 296afa17a50SWolfram Sang 297afa17a50SWolfram Sang frame->can_id |= can_id >> 1; 298afa17a50SWolfram Sang if (can_id & 1) 299afa17a50SWolfram Sang frame->can_id |= CAN_RTR_FLAG; 300afa17a50SWolfram Sang frame->can_dlc = in_8(®s->rx.dlr) & 0xf; 301afa17a50SWolfram Sang 302afa17a50SWolfram Sang if (!(frame->can_id & CAN_RTR_FLAG)) { 303afa17a50SWolfram Sang void __iomem *data = ®s->rx.dsr1_0; 304afa17a50SWolfram Sang u16 *payload = (u16 *)frame->data; 3050285e7ceSWolfram Sang 306afa17a50SWolfram Sang for (i = 0; i < (frame->can_dlc + 1) / 2; i++) { 307afa17a50SWolfram Sang *payload++ = in_be16(data); 308afa17a50SWolfram Sang data += 2 + _MSCAN_RESERVED_DSR_SIZE; 309afa17a50SWolfram Sang } 310afa17a50SWolfram Sang } 311afa17a50SWolfram Sang 312afa17a50SWolfram Sang out_8(®s->canrflg, MSCAN_RXF); 313afa17a50SWolfram Sang } 314afa17a50SWolfram Sang 315afa17a50SWolfram Sang static void mscan_get_err_frame(struct net_device *dev, struct can_frame *frame, 316afa17a50SWolfram Sang u8 canrflg) 317afa17a50SWolfram Sang { 318afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev); 319afa17a50SWolfram Sang struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; 320afa17a50SWolfram Sang struct net_device_stats *stats = &dev->stats; 321afa17a50SWolfram Sang enum can_state old_state; 322afa17a50SWolfram Sang 323afa17a50SWolfram Sang dev_dbg(dev->dev.parent, "error interrupt (canrflg=%#x)\n", canrflg); 324afa17a50SWolfram Sang frame->can_id = CAN_ERR_FLAG; 325afa17a50SWolfram Sang 326afa17a50SWolfram Sang if (canrflg & MSCAN_OVRIF) { 327afa17a50SWolfram Sang frame->can_id |= CAN_ERR_CRTL; 328afa17a50SWolfram Sang frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; 329afa17a50SWolfram Sang stats->rx_over_errors++; 330afa17a50SWolfram Sang stats->rx_errors++; 3310285e7ceSWolfram Sang } else { 332afa17a50SWolfram Sang frame->data[1] = 0; 3330285e7ceSWolfram Sang } 334afa17a50SWolfram Sang 335afa17a50SWolfram Sang old_state = check_set_state(dev, canrflg); 336afa17a50SWolfram Sang /* State changed */ 337afa17a50SWolfram Sang if (old_state != priv->can.state) { 338afa17a50SWolfram Sang switch (priv->can.state) { 339afa17a50SWolfram Sang case CAN_STATE_ERROR_WARNING: 340afa17a50SWolfram Sang frame->can_id |= CAN_ERR_CRTL; 341afa17a50SWolfram Sang priv->can.can_stats.error_warning++; 342afa17a50SWolfram Sang if ((priv->shadow_statflg & MSCAN_RSTAT_MSK) < 343afa17a50SWolfram Sang (canrflg & MSCAN_RSTAT_MSK)) 344afa17a50SWolfram Sang frame->data[1] |= CAN_ERR_CRTL_RX_WARNING; 345afa17a50SWolfram Sang if ((priv->shadow_statflg & MSCAN_TSTAT_MSK) < 346afa17a50SWolfram Sang (canrflg & MSCAN_TSTAT_MSK)) 347afa17a50SWolfram Sang frame->data[1] |= CAN_ERR_CRTL_TX_WARNING; 348afa17a50SWolfram Sang break; 349afa17a50SWolfram Sang case CAN_STATE_ERROR_PASSIVE: 350afa17a50SWolfram Sang frame->can_id |= CAN_ERR_CRTL; 351afa17a50SWolfram Sang priv->can.can_stats.error_passive++; 352afa17a50SWolfram Sang frame->data[1] |= CAN_ERR_CRTL_RX_PASSIVE; 353afa17a50SWolfram Sang break; 354afa17a50SWolfram Sang case CAN_STATE_BUS_OFF: 355afa17a50SWolfram Sang frame->can_id |= CAN_ERR_BUSOFF; 356afa17a50SWolfram Sang /* 357afa17a50SWolfram Sang * The MSCAN on the MPC5200 does recover from bus-off 358afa17a50SWolfram Sang * automatically. To avoid that we stop the chip doing 359afa17a50SWolfram Sang * a light-weight stop (we are in irq-context). 360afa17a50SWolfram Sang */ 361afa17a50SWolfram Sang out_8(®s->cantier, 0); 362afa17a50SWolfram Sang out_8(®s->canrier, 0); 36359179ea6SWolfram Sang setbits8(®s->canctl0, MSCAN_SLPRQ | MSCAN_INITRQ); 364afa17a50SWolfram Sang can_bus_off(dev); 365afa17a50SWolfram Sang break; 366afa17a50SWolfram Sang default: 367afa17a50SWolfram Sang break; 368afa17a50SWolfram Sang } 369afa17a50SWolfram Sang } 370afa17a50SWolfram Sang priv->shadow_statflg = canrflg & MSCAN_STAT_MSK; 371afa17a50SWolfram Sang frame->can_dlc = CAN_ERR_DLC; 372afa17a50SWolfram Sang out_8(®s->canrflg, MSCAN_ERR_IF); 373afa17a50SWolfram Sang } 374afa17a50SWolfram Sang 375afa17a50SWolfram Sang static int mscan_rx_poll(struct napi_struct *napi, int quota) 376afa17a50SWolfram Sang { 377afa17a50SWolfram Sang struct mscan_priv *priv = container_of(napi, struct mscan_priv, napi); 378afa17a50SWolfram Sang struct net_device *dev = napi->dev; 379afa17a50SWolfram Sang struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; 380afa17a50SWolfram Sang struct net_device_stats *stats = &dev->stats; 381afa17a50SWolfram Sang int npackets = 0; 382afa17a50SWolfram Sang int ret = 1; 383afa17a50SWolfram Sang struct sk_buff *skb; 384afa17a50SWolfram Sang struct can_frame *frame; 385afa17a50SWolfram Sang u8 canrflg; 386afa17a50SWolfram Sang 38768bd7422SWolfram Sang while (npackets < quota) { 38868bd7422SWolfram Sang canrflg = in_8(®s->canrflg); 38968bd7422SWolfram Sang if (!(canrflg & (MSCAN_RXF | MSCAN_ERR_IF))) 39068bd7422SWolfram Sang break; 391afa17a50SWolfram Sang 392afa17a50SWolfram Sang skb = alloc_can_skb(dev, &frame); 393afa17a50SWolfram Sang if (!skb) { 394afa17a50SWolfram Sang if (printk_ratelimit()) 395afa17a50SWolfram Sang dev_notice(dev->dev.parent, "packet dropped\n"); 396afa17a50SWolfram Sang stats->rx_dropped++; 397afa17a50SWolfram Sang out_8(®s->canrflg, canrflg); 398afa17a50SWolfram Sang continue; 399afa17a50SWolfram Sang } 400afa17a50SWolfram Sang 401afa17a50SWolfram Sang if (canrflg & MSCAN_RXF) 402afa17a50SWolfram Sang mscan_get_rx_frame(dev, frame); 403afa17a50SWolfram Sang else if (canrflg & MSCAN_ERR_IF) 404afa17a50SWolfram Sang mscan_get_err_frame(dev, frame, canrflg); 405afa17a50SWolfram Sang 406afa17a50SWolfram Sang stats->rx_packets++; 407afa17a50SWolfram Sang stats->rx_bytes += frame->can_dlc; 408afa17a50SWolfram Sang npackets++; 409afa17a50SWolfram Sang netif_receive_skb(skb); 410afa17a50SWolfram Sang } 411afa17a50SWolfram Sang 412afa17a50SWolfram Sang if (!(in_8(®s->canrflg) & (MSCAN_RXF | MSCAN_ERR_IF))) { 413afa17a50SWolfram Sang napi_complete(&priv->napi); 414afa17a50SWolfram Sang clear_bit(F_RX_PROGRESS, &priv->flags); 415afa17a50SWolfram Sang if (priv->can.state < CAN_STATE_BUS_OFF) 416afa17a50SWolfram Sang out_8(®s->canrier, priv->shadow_canrier); 417afa17a50SWolfram Sang ret = 0; 418afa17a50SWolfram Sang } 419afa17a50SWolfram Sang return ret; 420afa17a50SWolfram Sang } 421afa17a50SWolfram Sang 422afa17a50SWolfram Sang static irqreturn_t mscan_isr(int irq, void *dev_id) 423afa17a50SWolfram Sang { 424afa17a50SWolfram Sang struct net_device *dev = (struct net_device *)dev_id; 425afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev); 426afa17a50SWolfram Sang struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; 427afa17a50SWolfram Sang struct net_device_stats *stats = &dev->stats; 428afa17a50SWolfram Sang u8 cantier, cantflg, canrflg; 429afa17a50SWolfram Sang irqreturn_t ret = IRQ_NONE; 430afa17a50SWolfram Sang 431afa17a50SWolfram Sang cantier = in_8(®s->cantier) & MSCAN_TXE; 432afa17a50SWolfram Sang cantflg = in_8(®s->cantflg) & cantier; 433afa17a50SWolfram Sang 434afa17a50SWolfram Sang if (cantier && cantflg) { 435afa17a50SWolfram Sang struct list_head *tmp, *pos; 436afa17a50SWolfram Sang 437afa17a50SWolfram Sang list_for_each_safe(pos, tmp, &priv->tx_head) { 438afa17a50SWolfram Sang struct tx_queue_entry *entry = 439afa17a50SWolfram Sang list_entry(pos, struct tx_queue_entry, list); 440afa17a50SWolfram Sang u8 mask = entry->mask; 441afa17a50SWolfram Sang 442afa17a50SWolfram Sang if (!(cantflg & mask)) 443afa17a50SWolfram Sang continue; 444afa17a50SWolfram Sang 445afa17a50SWolfram Sang out_8(®s->cantbsel, mask); 446afa17a50SWolfram Sang stats->tx_bytes += in_8(®s->tx.dlr); 447afa17a50SWolfram Sang stats->tx_packets++; 448afa17a50SWolfram Sang can_get_echo_skb(dev, entry->id); 449afa17a50SWolfram Sang priv->tx_active &= ~mask; 450afa17a50SWolfram Sang list_del(pos); 451afa17a50SWolfram Sang } 452afa17a50SWolfram Sang 453afa17a50SWolfram Sang if (list_empty(&priv->tx_head)) { 454afa17a50SWolfram Sang clear_bit(F_TX_WAIT_ALL, &priv->flags); 455afa17a50SWolfram Sang clear_bit(F_TX_PROGRESS, &priv->flags); 456afa17a50SWolfram Sang priv->cur_pri = 0; 4570285e7ceSWolfram Sang } else { 458afa17a50SWolfram Sang dev->trans_start = jiffies; 4590285e7ceSWolfram Sang } 460afa17a50SWolfram Sang 461afa17a50SWolfram Sang if (!test_bit(F_TX_WAIT_ALL, &priv->flags)) 462afa17a50SWolfram Sang netif_wake_queue(dev); 463afa17a50SWolfram Sang 464afa17a50SWolfram Sang out_8(®s->cantier, priv->tx_active); 465afa17a50SWolfram Sang ret = IRQ_HANDLED; 466afa17a50SWolfram Sang } 467afa17a50SWolfram Sang 468afa17a50SWolfram Sang canrflg = in_8(®s->canrflg); 469afa17a50SWolfram Sang if ((canrflg & ~MSCAN_STAT_MSK) && 470afa17a50SWolfram Sang !test_and_set_bit(F_RX_PROGRESS, &priv->flags)) { 471afa17a50SWolfram Sang if (canrflg & ~MSCAN_STAT_MSK) { 472afa17a50SWolfram Sang priv->shadow_canrier = in_8(®s->canrier); 473afa17a50SWolfram Sang out_8(®s->canrier, 0); 474afa17a50SWolfram Sang napi_schedule(&priv->napi); 475afa17a50SWolfram Sang ret = IRQ_HANDLED; 4760285e7ceSWolfram Sang } else { 477afa17a50SWolfram Sang clear_bit(F_RX_PROGRESS, &priv->flags); 478afa17a50SWolfram Sang } 4790285e7ceSWolfram Sang } 480afa17a50SWolfram Sang return ret; 481afa17a50SWolfram Sang } 482afa17a50SWolfram Sang 483afa17a50SWolfram Sang static int mscan_do_set_mode(struct net_device *dev, enum can_mode mode) 484afa17a50SWolfram Sang { 485afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev); 486afa17a50SWolfram Sang int ret = 0; 487afa17a50SWolfram Sang 488afa17a50SWolfram Sang if (!priv->open_time) 489afa17a50SWolfram Sang return -EINVAL; 490afa17a50SWolfram Sang 491afa17a50SWolfram Sang switch (mode) { 492afa17a50SWolfram Sang case CAN_MODE_START: 493afa17a50SWolfram Sang if (priv->can.state <= CAN_STATE_BUS_OFF) 494afa17a50SWolfram Sang mscan_set_mode(dev, MSCAN_INIT_MODE); 495afa17a50SWolfram Sang ret = mscan_start(dev); 496afa17a50SWolfram Sang if (ret) 497afa17a50SWolfram Sang break; 498afa17a50SWolfram Sang if (netif_queue_stopped(dev)) 499afa17a50SWolfram Sang netif_wake_queue(dev); 500afa17a50SWolfram Sang break; 501afa17a50SWolfram Sang 502afa17a50SWolfram Sang default: 503afa17a50SWolfram Sang ret = -EOPNOTSUPP; 504afa17a50SWolfram Sang break; 505afa17a50SWolfram Sang } 506afa17a50SWolfram Sang return ret; 507afa17a50SWolfram Sang } 508afa17a50SWolfram Sang 509afa17a50SWolfram Sang static int mscan_do_set_bittiming(struct net_device *dev) 510afa17a50SWolfram Sang { 511afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev); 512afa17a50SWolfram Sang struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; 513afa17a50SWolfram Sang struct can_bittiming *bt = &priv->can.bittiming; 514afa17a50SWolfram Sang u8 btr0, btr1; 515afa17a50SWolfram Sang 516afa17a50SWolfram Sang btr0 = BTR0_SET_BRP(bt->brp) | BTR0_SET_SJW(bt->sjw); 517afa17a50SWolfram Sang btr1 = (BTR1_SET_TSEG1(bt->prop_seg + bt->phase_seg1) | 518afa17a50SWolfram Sang BTR1_SET_TSEG2(bt->phase_seg2) | 519afa17a50SWolfram Sang BTR1_SET_SAM(priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)); 520afa17a50SWolfram Sang 521afa17a50SWolfram Sang dev_info(dev->dev.parent, "setting BTR0=0x%02x BTR1=0x%02x\n", 522afa17a50SWolfram Sang btr0, btr1); 523afa17a50SWolfram Sang 524afa17a50SWolfram Sang out_8(®s->canbtr0, btr0); 525afa17a50SWolfram Sang out_8(®s->canbtr1, btr1); 526afa17a50SWolfram Sang 527afa17a50SWolfram Sang return 0; 528afa17a50SWolfram Sang } 529afa17a50SWolfram Sang 530afa17a50SWolfram Sang static int mscan_open(struct net_device *dev) 531afa17a50SWolfram Sang { 532afa17a50SWolfram Sang int ret; 533afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev); 534afa17a50SWolfram Sang struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; 535afa17a50SWolfram Sang 536afa17a50SWolfram Sang /* common open */ 537afa17a50SWolfram Sang ret = open_candev(dev); 538afa17a50SWolfram Sang if (ret) 539afa17a50SWolfram Sang return ret; 540afa17a50SWolfram Sang 541afa17a50SWolfram Sang napi_enable(&priv->napi); 542afa17a50SWolfram Sang 543afa17a50SWolfram Sang ret = request_irq(dev->irq, mscan_isr, 0, dev->name, dev); 544afa17a50SWolfram Sang if (ret < 0) { 545afa17a50SWolfram Sang napi_disable(&priv->napi); 546afa17a50SWolfram Sang printk(KERN_ERR "%s - failed to attach interrupt\n", 547afa17a50SWolfram Sang dev->name); 548afa17a50SWolfram Sang return ret; 549afa17a50SWolfram Sang } 550afa17a50SWolfram Sang 551afa17a50SWolfram Sang priv->open_time = jiffies; 552afa17a50SWolfram Sang 55359179ea6SWolfram Sang clrbits8(®s->canctl1, MSCAN_LISTEN); 554afa17a50SWolfram Sang 555afa17a50SWolfram Sang ret = mscan_start(dev); 556afa17a50SWolfram Sang if (ret) 557afa17a50SWolfram Sang return ret; 558afa17a50SWolfram Sang 559afa17a50SWolfram Sang netif_start_queue(dev); 560afa17a50SWolfram Sang 561afa17a50SWolfram Sang return 0; 562afa17a50SWolfram Sang } 563afa17a50SWolfram Sang 564afa17a50SWolfram Sang static int mscan_close(struct net_device *dev) 565afa17a50SWolfram Sang { 566afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev); 567afa17a50SWolfram Sang struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; 568afa17a50SWolfram Sang 569afa17a50SWolfram Sang netif_stop_queue(dev); 570afa17a50SWolfram Sang napi_disable(&priv->napi); 571afa17a50SWolfram Sang 572afa17a50SWolfram Sang out_8(®s->cantier, 0); 573afa17a50SWolfram Sang out_8(®s->canrier, 0); 574afa17a50SWolfram Sang mscan_set_mode(dev, MSCAN_INIT_MODE); 575afa17a50SWolfram Sang close_candev(dev); 576afa17a50SWolfram Sang free_irq(dev->irq, dev); 577afa17a50SWolfram Sang priv->open_time = 0; 578afa17a50SWolfram Sang 579afa17a50SWolfram Sang return 0; 580afa17a50SWolfram Sang } 581afa17a50SWolfram Sang 582afa17a50SWolfram Sang static const struct net_device_ops mscan_netdev_ops = { 583afa17a50SWolfram Sang .ndo_open = mscan_open, 584afa17a50SWolfram Sang .ndo_stop = mscan_close, 585afa17a50SWolfram Sang .ndo_start_xmit = mscan_start_xmit, 586afa17a50SWolfram Sang }; 587afa17a50SWolfram Sang 588afa17a50SWolfram Sang int register_mscandev(struct net_device *dev, int clock_src) 589afa17a50SWolfram Sang { 590afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev); 591afa17a50SWolfram Sang struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; 592afa17a50SWolfram Sang u8 ctl1; 593afa17a50SWolfram Sang 594afa17a50SWolfram Sang ctl1 = in_8(®s->canctl1); 595afa17a50SWolfram Sang if (clock_src) 596afa17a50SWolfram Sang ctl1 |= MSCAN_CLKSRC; 597afa17a50SWolfram Sang else 598afa17a50SWolfram Sang ctl1 &= ~MSCAN_CLKSRC; 599afa17a50SWolfram Sang 600afa17a50SWolfram Sang ctl1 |= MSCAN_CANE; 601afa17a50SWolfram Sang out_8(®s->canctl1, ctl1); 602afa17a50SWolfram Sang udelay(100); 603afa17a50SWolfram Sang 604afa17a50SWolfram Sang /* acceptance mask/acceptance code (accept everything) */ 605afa17a50SWolfram Sang out_be16(®s->canidar1_0, 0); 606afa17a50SWolfram Sang out_be16(®s->canidar3_2, 0); 607afa17a50SWolfram Sang out_be16(®s->canidar5_4, 0); 608afa17a50SWolfram Sang out_be16(®s->canidar7_6, 0); 609afa17a50SWolfram Sang 610afa17a50SWolfram Sang out_be16(®s->canidmr1_0, 0xffff); 611afa17a50SWolfram Sang out_be16(®s->canidmr3_2, 0xffff); 612afa17a50SWolfram Sang out_be16(®s->canidmr5_4, 0xffff); 613afa17a50SWolfram Sang out_be16(®s->canidmr7_6, 0xffff); 614afa17a50SWolfram Sang /* Two 32 bit Acceptance Filters */ 615afa17a50SWolfram Sang out_8(®s->canidac, MSCAN_AF_32BIT); 616afa17a50SWolfram Sang 617afa17a50SWolfram Sang mscan_set_mode(dev, MSCAN_INIT_MODE); 618afa17a50SWolfram Sang 619afa17a50SWolfram Sang return register_candev(dev); 620afa17a50SWolfram Sang } 621afa17a50SWolfram Sang 622afa17a50SWolfram Sang void unregister_mscandev(struct net_device *dev) 623afa17a50SWolfram Sang { 624afa17a50SWolfram Sang struct mscan_priv *priv = netdev_priv(dev); 625afa17a50SWolfram Sang struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; 626afa17a50SWolfram Sang mscan_set_mode(dev, MSCAN_INIT_MODE); 62759179ea6SWolfram Sang clrbits8(®s->canctl1, MSCAN_CANE); 628afa17a50SWolfram Sang unregister_candev(dev); 629afa17a50SWolfram Sang } 630afa17a50SWolfram Sang 631afa17a50SWolfram Sang struct net_device *alloc_mscandev(void) 632afa17a50SWolfram Sang { 633afa17a50SWolfram Sang struct net_device *dev; 634afa17a50SWolfram Sang struct mscan_priv *priv; 635afa17a50SWolfram Sang int i; 636afa17a50SWolfram Sang 637afa17a50SWolfram Sang dev = alloc_candev(sizeof(struct mscan_priv), MSCAN_ECHO_SKB_MAX); 638afa17a50SWolfram Sang if (!dev) 639afa17a50SWolfram Sang return NULL; 640afa17a50SWolfram Sang priv = netdev_priv(dev); 641afa17a50SWolfram Sang 642afa17a50SWolfram Sang dev->netdev_ops = &mscan_netdev_ops; 643afa17a50SWolfram Sang 644afa17a50SWolfram Sang dev->flags |= IFF_ECHO; /* we support local echo */ 645afa17a50SWolfram Sang 646afa17a50SWolfram Sang netif_napi_add(dev, &priv->napi, mscan_rx_poll, 8); 647afa17a50SWolfram Sang 648afa17a50SWolfram Sang priv->can.bittiming_const = &mscan_bittiming_const; 649afa17a50SWolfram Sang priv->can.do_set_bittiming = mscan_do_set_bittiming; 650afa17a50SWolfram Sang priv->can.do_set_mode = mscan_do_set_mode; 651afa17a50SWolfram Sang 652afa17a50SWolfram Sang for (i = 0; i < TX_QUEUE_SIZE; i++) { 653afa17a50SWolfram Sang priv->tx_queue[i].id = i; 654afa17a50SWolfram Sang priv->tx_queue[i].mask = 1 << i; 655afa17a50SWolfram Sang } 656afa17a50SWolfram Sang 657afa17a50SWolfram Sang return dev; 658afa17a50SWolfram Sang } 659afa17a50SWolfram Sang 660afa17a50SWolfram Sang MODULE_AUTHOR("Andrey Volkov <avolkov@varma-el.com>"); 661afa17a50SWolfram Sang MODULE_LICENSE("GPL v2"); 662afa17a50SWolfram Sang MODULE_DESCRIPTION("CAN port driver for a MSCAN based chips"); 663