diff options
Diffstat (limited to 'drivers/net/can/mscan')
| -rw-r--r-- | drivers/net/can/mscan/Makefile | 5 | ||||
| -rw-r--r-- | drivers/net/can/mscan/mpc52xx_can.c | 279 | ||||
| -rw-r--r-- | drivers/net/can/mscan/mscan.c | 699 | ||||
| -rw-r--r-- | drivers/net/can/mscan/mscan.h | 262 |
4 files changed, 1245 insertions, 0 deletions
diff --git a/drivers/net/can/mscan/Makefile b/drivers/net/can/mscan/Makefile new file mode 100644 index 0000000..2bd9f04 --- /dev/null +++ b/drivers/net/can/mscan/Makefile @@ -0,0 +1,5 @@ + +obj-$(CONFIG_CAN_MPC52XX) += mscan-mpc52xx.o +mscan-mpc52xx-objs := mscan.o mpc52xx_can.o + +ccflags-$(CONFIG_CAN_DEBUG_DEVICES) := -DDEBUG diff --git a/drivers/net/can/mscan/mpc52xx_can.c b/drivers/net/can/mscan/mpc52xx_can.c new file mode 100644 index 0000000..4707a82 --- /dev/null +++ b/drivers/net/can/mscan/mpc52xx_can.c @@ -0,0 +1,279 @@ +/* + * CAN bus driver for the Freescale MPC5xxx embedded CPU. + * + * Copyright (C) 2004-2005 Andrey Volkov <avolkov@varma-el.com>, + * Varma Electronics Oy + * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com> + * Copyright (C) 2009 Wolfram Sang, Pengutronix <w.sang@pengutronix.de> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the version 2 of the GNU General Public License + * as published by the Free Software Foundation + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/netdevice.h> +#include <linux/can.h> +#include <linux/can/dev.h> +#include <linux/of_platform.h> +#include <sysdev/fsl_soc.h> +#include <linux/io.h> +#include <asm/mpc52xx.h> + +#include "mscan.h" + + +#define DRV_NAME "mpc5xxx_can" + +static struct of_device_id mpc52xx_cdm_ids[] __devinitdata = { + { .compatible = "fsl,mpc5200-cdm", }, + { .compatible = "fsl,mpc5200b-cdm", }, + {} +}; + +/* + * Get the frequency of the external oscillator clock connected + * to the SYS_XTAL_IN pin, or return 0 if it cannot be determined. + */ +static unsigned int __devinit mpc52xx_can_xtal_freq(struct of_device *of) +{ + struct mpc52xx_cdm __iomem *cdm; + struct device_node *np_cdm; + unsigned int freq; + u32 val; + + freq = mpc5xxx_get_bus_frequency(of->node); + if (!freq) + return 0; + + /* + * Determine SYS_XTAL_IN frequency from the clock domain settings + */ + np_cdm = of_find_matching_node(NULL, mpc52xx_cdm_ids); + if (!np_cdm) { + dev_err(&of->dev, "can't get clock node!\n"); + return 0; + } + cdm = of_iomap(np_cdm, 0); + of_node_put(np_cdm); + + if (in_8(&cdm->ipb_clk_sel) & 0x1) + freq *= 2; + val = in_be32(&cdm->rstcfg); + if (val & (1 << 5)) + freq *= 8; + else + freq *= 4; + if (val & (1 << 6)) + freq /= 12; + else + freq /= 16; + + iounmap(cdm); + + return freq; +} + +/* + * Get frequency of the MSCAN clock source + * + * Either the oscillator clock (SYS_XTAL_IN) or the IP bus clock (IP_CLK) + * can be selected. According to the MPC5200 user's manual, the oscillator + * clock is the better choice as it has less jitter but due to a hardware + * bug, it can not be selected for the old MPC5200 Rev. A chips. + */ + +static unsigned int __devinit mpc52xx_can_clock_freq(struct of_device *of, + int clock_src) +{ + unsigned int pvr; + + pvr = mfspr(SPRN_PVR); + + if (clock_src == MSCAN_CLKSRC_BUS || pvr == 0x80822011) + return mpc5xxx_get_bus_frequency(of->node); + + return mpc52xx_can_xtal_freq(of); +} + +static int __devinit mpc5xxx_can_probe(struct of_device *ofdev, + const struct of_device_id *id) +{ + struct device_node *np = ofdev->node; + struct net_device *dev; + struct mscan_priv *priv; + void __iomem *base; + const char *clk_src; + int err, irq, clock_src; + + base = of_iomap(ofdev->node, 0); + if (!base) { + dev_err(&ofdev->dev, "couldn't ioremap\n"); + err = -ENOMEM; + goto exit_release_mem; + } + + irq = irq_of_parse_and_map(np, 0); + if (!irq) { + dev_err(&ofdev->dev, "no irq found\n"); + err = -ENODEV; + goto exit_unmap_mem; + } + + dev = alloc_mscandev(); + if (!dev) { + err = -ENOMEM; + goto exit_dispose_irq; + } + + priv = netdev_priv(dev); + priv->reg_base = base; + dev->irq = irq; + + /* + * Either the oscillator clock (SYS_XTAL_IN) or the IP bus clock + * (IP_CLK) can be selected as MSCAN clock source. According to + * the MPC5200 user's manual, the oscillator clock is the better + * choice as it has less jitter. For this reason, it is selected + * by default. + */ + clk_src = of_get_property(np, "fsl,mscan-clk-src", NULL); + if (clk_src && strcmp(clk_src, "ip") == 0) + clock_src = MSCAN_CLKSRC_BUS; + else + clock_src = MSCAN_CLKSRC_XTAL; + priv->can.clock.freq = mpc52xx_can_clock_freq(ofdev, clock_src); + if (!priv->can.clock.freq) { + dev_err(&ofdev->dev, "couldn't get MSCAN clock frequency\n"); + err = -ENODEV; + goto exit_free_mscan; + } + + SET_NETDEV_DEV(dev, &ofdev->dev); + + err = register_mscandev(dev, clock_src); + if (err) { + dev_err(&ofdev->dev, "registering %s failed (err=%d)\n", + DRV_NAME, err); + goto exit_free_mscan; + } + + dev_set_drvdata(&ofdev->dev, dev); + + dev_info(&ofdev->dev, "MSCAN at 0x%p, irq %d, clock %d Hz\n", + priv->reg_base, dev->irq, priv->can.clock.freq); + + return 0; + +exit_free_mscan: + free_candev(dev); +exit_dispose_irq: + irq_dispose_mapping(irq); +exit_unmap_mem: + iounmap(base); +exit_release_mem: + return err; +} + +static int __devexit mpc5xxx_can_remove(struct of_device *ofdev) +{ + struct net_device *dev = dev_get_drvdata(&ofdev->dev); + struct mscan_priv *priv = netdev_priv(dev); + + dev_set_drvdata(&ofdev->dev, NULL); + + unregister_mscandev(dev); + iounmap(priv->reg_base); + irq_dispose_mapping(dev->irq); + free_candev(dev); + + return 0; +} + +#ifdef CONFIG_PM +static struct mscan_regs saved_regs; +static int mpc5xxx_can_suspend(struct of_device *ofdev, pm_message_t state) +{ + struct net_device *dev = dev_get_drvdata(&ofdev->dev); + struct mscan_priv *priv = netdev_priv(dev); + struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; + + _memcpy_fromio(&saved_regs, regs, sizeof(*regs)); + + return 0; +} + +static int mpc5xxx_can_resume(struct of_device *ofdev) +{ + struct net_device *dev = dev_get_drvdata(&ofdev->dev); + struct mscan_priv *priv = netdev_priv(dev); + struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; + + regs->canctl0 |= MSCAN_INITRQ; + while ((regs->canctl1 & MSCAN_INITAK) == 0) + udelay(10); + + regs->canctl1 = saved_regs.canctl1; + regs->canbtr0 = saved_regs.canbtr0; + regs->canbtr1 = saved_regs.canbtr1; + regs->canidac = saved_regs.canidac; + + /* restore masks, buffers etc. */ + _memcpy_toio(®s->canidar1_0, (void *)&saved_regs.canidar1_0, + sizeof(*regs) - offsetof(struct mscan_regs, canidar1_0)); + + regs->canctl0 &= ~MSCAN_INITRQ; + regs->cantbsel = saved_regs.cantbsel; + regs->canrier = saved_regs.canrier; + regs->cantier = saved_regs.cantier; + regs->canctl0 = saved_regs.canctl0; + + return 0; +} +#endif + +static struct of_device_id __devinitdata mpc5xxx_can_table[] = { + {.compatible = "fsl,mpc5200-mscan"}, + {.compatible = "fsl,mpc5200b-mscan"}, + {}, +}; + +static struct of_platform_driver mpc5xxx_can_driver = { + .owner = THIS_MODULE, + .name = "mpc5xxx_can", + .probe = mpc5xxx_can_probe, + .remove = __devexit_p(mpc5xxx_can_remove), +#ifdef CONFIG_PM + .suspend = mpc5xxx_can_suspend, + .resume = mpc5xxx_can_resume, +#endif + .match_table = mpc5xxx_can_table, +}; + +static int __init mpc5xxx_can_init(void) +{ + return of_register_platform_driver(&mpc5xxx_can_driver); +} +module_init(mpc5xxx_can_init); + +static void __exit mpc5xxx_can_exit(void) +{ + return of_unregister_platform_driver(&mpc5xxx_can_driver); +}; +module_exit(mpc5xxx_can_exit); + +MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>"); +MODULE_DESCRIPTION("Freescale MPC5200 CAN driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/net/can/mscan/mscan.c b/drivers/net/can/mscan/mscan.c new file mode 100644 index 0000000..49542ca --- /dev/null +++ b/drivers/net/can/mscan/mscan.c @@ -0,0 +1,699 @@ +/* + * CAN bus driver for the alone generic (as possible as) MSCAN controller. + * + * Copyright (C) 2005-2006 Andrey Volkov <avolkov@varma-el.com>, + * Varma Electronics Oy + * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com> + * Copytight (C) 2008-2009 Pengutronix <kernel@pengutronix.de> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the version 2 of the GNU General Public License + * as published by the Free Software Foundation + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <linux/netdevice.h> +#include <linux/if_arp.h> +#include <linux/if_ether.h> +#include <linux/list.h> +#include <linux/can.h> +#include <linux/can/dev.h> +#include <linux/can/error.h> +#include <linux/io.h> + +#include "mscan.h" + +#define MSCAN_NORMAL_MODE 0 +#define MSCAN_SLEEP_MODE MSCAN_SLPRQ +#define MSCAN_INIT_MODE (MSCAN_INITRQ | MSCAN_SLPRQ) +#define MSCAN_POWEROFF_MODE (MSCAN_CSWAI | MSCAN_SLPRQ) +#define MSCAN_SET_MODE_RETRIES 255 +#define MSCAN_ECHO_SKB_MAX 3 + +#define BTR0_BRP_MASK 0x3f +#define BTR0_SJW_SHIFT 6 +#define BTR0_SJW_MASK (0x3 << BTR0_SJW_SHIFT) + +#define BTR1_TSEG1_MASK 0xf +#define BTR1_TSEG2_SHIFT 4 +#define BTR1_TSEG2_MASK (0x7 << BTR1_TSEG2_SHIFT) +#define BTR1_SAM_SHIFT 7 + +#define BTR0_SET_BRP(brp) (((brp) - 1) & BTR0_BRP_MASK) +#define BTR0_SET_SJW(sjw) ((((sjw) - 1) << BTR0_SJW_SHIFT) & \ + BTR0_SJW_MASK) + +#define BTR1_SET_TSEG1(tseg1) (((tseg1) - 1) & BTR1_TSEG1_MASK) +#define BTR1_SET_TSEG2(tseg2) ((((tseg2) - 1) << BTR1_TSEG2_SHIFT) & \ + BTR1_TSEG2_MASK) +#define BTR1_SET_SAM(sam) ((sam) ? 1 << BTR1_SAM_SHIFT : 0) + +static struct can_bittiming_const mscan_bittiming_const = { + .name = "mscan", + .tseg1_min = 4, + .tseg1_max = 16, + .tseg2_min = 2, + .tseg2_max = 8, + .sjw_max = 4, + .brp_min = 1, + .brp_max = 64, + .brp_inc = 1, +}; + +struct mscan_state { + u8 mode; + u8 canrier; + u8 cantier; +}; + +#define F_RX_PROGRESS 0 +#define F_TX_PROGRESS 1 +#define F_TX_WAIT_ALL 2 + +static enum can_state state_map[] = { + CAN_STATE_ERROR_ACTIVE, + CAN_STATE_ERROR_WARNING, + CAN_STATE_ERROR_PASSIVE, + CAN_STATE_BUS_OFF +}; + +static int mscan_set_mode(struct net_device *dev, u8 mode) +{ + struct mscan_priv *priv = netdev_priv(dev); + struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; + int ret = 0; + int i; + u8 canctl1; + + if (mode != MSCAN_NORMAL_MODE) { + + if (priv->tx_active) { + /* Abort transfers before going to sleep */# + out_8(®s->cantarq, priv->tx_active); + /* Suppress TX done interrupts */ + out_8(®s->cantier, 0); + } + + canctl1 = in_8(®s->canctl1); + if ((mode & MSCAN_SLPRQ) && (canctl1 & MSCAN_SLPAK) == 0) { + out_8(®s->canctl0, + in_8(®s->canctl0) | MSCAN_SLPRQ); + for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) { + if (in_8(®s->canctl1) & MSCAN_SLPAK) + break; + udelay(100); + } + /* + * The mscan controller will fail to enter sleep mode, + * while there are irregular activities on bus, like + * somebody keeps retransmitting. This behavior is + * undocumented and seems to differ between mscan built + * in mpc5200b and mpc5200. We proceed in that case, + * since otherwise the slprq will be kept set and the + * controller will get stuck. NOTE: INITRQ or CSWAI + * will abort all active transmit actions, if still + * any, at once. + */ + if (i >= MSCAN_SET_MODE_RETRIES) + dev_dbg(dev->dev.parent, + "device failed to enter sleep mode. " + "We proceed anyhow.\n"); + else + priv->can.state = CAN_STATE_SLEEPING; + } + + if ((mode & MSCAN_INITRQ) && (canctl1 & MSCAN_INITAK) == 0) { + out_8(®s->canctl0, + in_8(®s->canctl0) | MSCAN_INITRQ); + for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) { + if (in_8(®s->canctl1) & MSCAN_INITAK) + break; + } + if (i >= MSCAN_SET_MODE_RETRIES) + ret = -ENODEV; + } + if (!ret) + priv->can.state = CAN_STATE_STOPPED; + + if (mode & MSCAN_CSWAI) + out_8(®s->canctl0, + in_8(®s->canctl0) | MSCAN_CSWAI); + + } else { + canctl1 = in_8(®s->canctl1); + if (canctl1 & (MSCAN_SLPAK | MSCAN_INITAK)) { + out_8(®s->canctl0, in_8(®s->canctl0) & + ~(MSCAN_SLPRQ | MSCAN_INITRQ)); + for (i = 0; i < MSCAN_SET_MODE_RETRIES; i++) { + canctl1 = in_8(®s->canctl1); + if (!(canctl1 & (MSCAN_INITAK | MSCAN_SLPAK))) + break; + } + if (i >= MSCAN_SET_MODE_RETRIES) + ret = -ENODEV; + else + priv->can.state = CAN_STATE_ERROR_ACTIVE; + } + } + return ret; +} + +static int mscan_start(struct net_device *dev) +{ + struct mscan_priv *priv = netdev_priv(dev); + struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; + u8 canrflg; + int err; + + out_8(®s->canrier, 0); + + INIT_LIST_HEAD(&priv->tx_head); + priv->prev_buf_id = 0; + priv->cur_pri = 0; + priv->tx_active = 0; + priv->shadow_canrier = 0; + priv->flags = 0; + + err = mscan_set_mode(dev, MSCAN_NORMAL_MODE); + if (err) + return err; + + canrflg = in_8(®s->canrflg); + priv->shadow_statflg = canrflg & MSCAN_STAT_MSK; + priv->can.state = state_map[max(MSCAN_STATE_RX(canrflg), + MSCAN_STATE_TX(canrflg))]; + out_8(®s->cantier, 0); + + /* Enable receive interrupts. */ + out_8(®s->canrier, MSCAN_OVRIE | MSCAN_RXFIE | MSCAN_CSCIE | + MSCAN_RSTATE1 | MSCAN_RSTATE0 | MSCAN_TSTATE1 | MSCAN_TSTATE0); + + return 0; +} + +static netdev_tx_t mscan_start_xmit(struct sk_buff *skb, struct net_device *dev) +{ + struct can_frame *frame = (struct can_frame *)skb->data; + struct mscan_priv *priv = netdev_priv(dev); + struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; + int i, rtr, buf_id; + u32 can_id; + + if (frame->can_dlc > 8) + return -EINVAL; + + out_8(®s->cantier, 0); + + i = ~priv->tx_active & MSCAN_TXE; + buf_id = ffs(i) - 1; + switch (hweight8(i)) { + case 0: + netif_stop_queue(dev); + dev_err(dev->dev.parent, "Tx Ring full when queue awake!\n"); + return NETDEV_TX_BUSY; + case 1: + /* + * if buf_id < 3, then current frame will be send out of order, + * since buffer with lower id have higher priority (hell..) + */ + netif_stop_queue(dev); + case 2: + if (buf_id < priv->prev_buf_id) { + priv->cur_pri++; + if (priv->cur_pri == 0xff) { + set_bit(F_TX_WAIT_ALL, &priv->flags); + netif_stop_queue(dev); + } + } + set_bit(F_TX_PROGRESS, &priv->flags); + break; + } + priv->prev_buf_id = buf_id; + out_8(®s->cantbsel, i); + + rtr = frame->can_id & CAN_RTR_FLAG; + + if (frame->can_id & CAN_EFF_FLAG) { + can_id = (frame->can_id & CAN_EFF_MASK) << 1; + if (rtr) + can_id |= 1; + out_be16(®s->tx.idr3_2, can_id); + + can_id >>= 16; + can_id = (can_id & 0x7) | ((can_id << 2) & 0xffe0) | (3 << 3); + } else { + can_id = (frame->can_id & CAN_SFF_MASK) << 5; + if (rtr) + can_id |= 1 << 4; + } + out_be16(®s->tx.idr1_0, can_id); + + if (!rtr) { + void __iomem *data = ®s->tx.dsr1_0; + u16 *payload = (u16 *) frame->data; + /* It is safe to write into dsr[dlc+1] */ + for (i = 0; i < (frame->can_dlc + 1) / 2; i++) { + out_be16(data, *payload++); + data += 2 + _MSCAN_RESERVED_DSR_SIZE; + } + } + + out_8(®s->tx.dlr, frame->can_dlc); + out_8(®s->tx.tbpr, priv->cur_pri); + + /* Start transmission. */ + out_8(®s->cantflg, 1 << buf_id); + + if (!test_bit(F_TX_PROGRESS, &priv->flags)) + dev->trans_start = jiffies; + + list_add_tail(&priv->tx_queue[buf_id].list, &priv->tx_head); + + can_put_echo_skb(skb, dev, buf_id); + + /* Enable interrupt. */ + priv->tx_active |= 1 << buf_id; + out_8(®s->cantier, priv->tx_active); + + return NETDEV_TX_OK; +} + +/* This function returns the old state to see where we came from */ +static enum can_state check_set_state(struct net_device *dev, u8 canrflg) +{ + struct mscan_priv *priv = netdev_priv(dev); + enum can_state state, old_state = priv->can.state; + + if (canrflg & MSCAN_CSCIF && old_state <= CAN_STATE_BUS_OFF) { + state = state_map[max(MSCAN_STATE_RX(canrflg), + MSCAN_STATE_TX(canrflg))]; + priv->can.state = state; + } + return old_state; +} + +static void mscan_get_rx_frame(struct net_device *dev, struct can_frame *frame) +{ + struct mscan_priv *priv = netdev_priv(dev); + struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; + u32 can_id; + int i; + + can_id = in_be16(®s->rx.idr1_0); + if (can_id & (1 << 3)) { + frame->can_id = CAN_EFF_FLAG; + can_id = ((can_id << 16) | in_be16(®s->rx.idr3_2)); + can_id = ((can_id & 0xffe00000) | + ((can_id & 0x7ffff) << 2)) >> 2; + } else { + can_id >>= 4; + frame->can_id = 0; + } + + frame->can_id |= can_id >> 1; + if (can_id & 1) + frame->can_id |= CAN_RTR_FLAG; + frame->can_dlc = in_8(®s->rx.dlr) & 0xf; + + if (!(frame->can_id & CAN_RTR_FLAG)) { + void __iomem *data = ®s->rx.dsr1_0; + u16 *payload = (u16 *) frame->data; + for (i = 0; i < (frame->can_dlc + 1) / 2; i++) { + *payload++ = in_be16(data); + data += 2 + _MSCAN_RESERVED_DSR_SIZE; + } + } + + out_8(®s->canrflg, MSCAN_RXF); +} + +static void mscan_get_err_frame(struct net_device *dev, struct can_frame *frame, + u8 canrflg) +{ + struct mscan_priv *priv = netdev_priv(dev); + struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; + struct net_device_stats *stats = &dev->stats; + enum can_state old_state; + + dev_dbg(dev->dev.parent, "error interrupt (canrflg=%#x)\n", canrflg); + frame->can_id = CAN_ERR_FLAG; + + if (canrflg & MSCAN_OVRIF) { + frame->can_id |= CAN_ERR_CRTL; + frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; + stats->rx_over_errors++; + stats->rx_errors++; + } else + frame->data[1] = 0; + + old_state = check_set_state(dev, canrflg); + /* State changed */ + if (old_state != priv->can.state) { + switch (priv->can.state) { + case CAN_STATE_ERROR_WARNING: + frame->can_id |= CAN_ERR_CRTL; + priv->can.can_stats.error_warning++; + if ((priv->shadow_statflg & MSCAN_RSTAT_MSK) < + (canrflg & MSCAN_RSTAT_MSK)) + frame->data[1] |= CAN_ERR_CRTL_RX_WARNING; + + if ((priv->shadow_statflg & MSCAN_TSTAT_MSK) < + (canrflg & MSCAN_TSTAT_MSK)) + frame->data[1] |= CAN_ERR_CRTL_TX_WARNING; + break; + case CAN_STATE_ERROR_PASSIVE: + frame->can_id |= CAN_ERR_CRTL; + priv->can.can_stats.error_passive++; + frame->data[1] |= CAN_ERR_CRTL_RX_PASSIVE; + break; + case CAN_STATE_BUS_OFF: + frame->can_id |= CAN_ERR_BUSOFF; + /* + * The MSCAN on the MPC5200 does recover from bus-off + * automatically. To avoid that we stop the chip doing + * a light-weight stop (we are in irq-context). + */ + out_8(®s->cantier, 0); + out_8(®s->canrier, 0); + out_8(®s->canctl0, in_8(®s->canctl0) | + MSCAN_SLPRQ | MSCAN_INITRQ); + can_bus_off(dev); + break; + default: + break; + } + } + priv->shadow_statflg = canrflg & MSCAN_STAT_MSK; + frame->can_dlc = CAN_ERR_DLC; + out_8(®s->canrflg, MSCAN_ERR_IF); +} + +static int mscan_rx_poll(struct napi_struct *napi, int quota) +{ + struct mscan_priv *priv = container_of(napi, struct mscan_priv, napi); + struct net_device *dev = napi->dev; + struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; + struct net_device_stats *stats = &dev->stats; + int npackets = 0; + int ret = 1; + struct sk_buff *skb; + struct can_frame *frame; + u8 canrflg; + + while (npackets < quota && ((canrflg = in_8(®s->canrflg)) & + (MSCAN_RXF | MSCAN_ERR_IF))) { + + skb = alloc_can_skb(dev, &frame); + if (!skb) { + if (printk_ratelimit()) + dev_notice(dev->dev.parent, "packet dropped\n"); + stats->rx_dropped++; + out_8(®s->canrflg, canrflg); + continue; + } + + if (canrflg & MSCAN_RXF) + mscan_get_rx_frame(dev, frame); + else if (canrflg & MSCAN_ERR_IF) + mscan_get_err_frame(dev, frame, canrflg); + + stats->rx_packets++; + stats->rx_bytes += frame->can_dlc; + npackets++; + netif_receive_skb(skb); + } + + if (!(in_8(®s->canrflg) & (MSCAN_RXF | MSCAN_ERR_IF))) { + napi_complete(&priv->napi); + clear_bit(F_RX_PROGRESS, &priv->flags); + if (priv->can.state < CAN_STATE_BUS_OFF) + out_8(®s->canrier, priv->shadow_canrier); + ret = 0; + } + return ret; +} + +static irqreturn_t mscan_isr(int irq, void *dev_id) +{ + struct net_device *dev = (struct net_device *)dev_id; + struct mscan_priv *priv = netdev_priv(dev); + struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; + struct net_device_stats *stats = &dev->stats; + u8 cantier, cantflg, canrflg; + irqreturn_t ret = IRQ_NONE; + + cantier = in_8(®s->cantier) & MSCAN_TXE; + cantflg = in_8(®s->cantflg) & cantier; + + if (cantier && cantflg) { + + struct list_head *tmp, *pos; + + list_for_each_safe(pos, tmp, &priv->tx_head) { + struct tx_queue_entry *entry = + list_entry(pos, struct tx_queue_entry, list); + u8 mask = entry->mask; + + if (!(cantflg & mask)) + continue; + + out_8(®s->cantbsel, mask); + stats->tx_bytes += in_8(®s->tx.dlr); + stats->tx_packets++; + can_get_echo_skb(dev, entry->id); + priv->tx_active &= ~mask; + list_del(pos); + } + + if (list_empty(&priv->tx_head)) { + clear_bit(F_TX_WAIT_ALL, &priv->flags); + clear_bit(F_TX_PROGRESS, &priv->flags); + priv->cur_pri = 0; + } else + dev->trans_start = jiffies; + + if (!test_bit(F_TX_WAIT_ALL, &priv->flags)) + netif_wake_queue(dev); + + out_8(®s->cantier, priv->tx_active); + ret = IRQ_HANDLED; + } + + canrflg = in_8(®s->canrflg); + if ((canrflg & ~MSCAN_STAT_MSK) && + !test_and_set_bit(F_RX_PROGRESS, &priv->flags)) { + if (canrflg & ~MSCAN_STAT_MSK) { + priv->shadow_canrier = in_8(®s->canrier); + out_8(®s->canrier, 0); + napi_schedule(&priv->napi); + ret = IRQ_HANDLED; + } else + clear_bit(F_RX_PROGRESS, &priv->flags); + } + return ret; +} + +static int mscan_do_set_mode(struct net_device *dev, enum can_mode mode) +{ + + struct mscan_priv *priv = netdev_priv(dev); + int ret = 0; + + if (!priv->open_time) + return -EINVAL; + + switch (mode) { + case CAN_MODE_SLEEP: + case CAN_MODE_STOP: + netif_stop_queue(dev); + mscan_set_mode(dev, + (mode == + CAN_MODE_STOP) ? MSCAN_INIT_MODE : + MSCAN_SLEEP_MODE); + break; + case CAN_MODE_START: + if (priv->can.state <= CAN_STATE_BUS_OFF) + mscan_set_mode(dev, MSCAN_INIT_MODE); + ret = mscan_start(dev); + if (ret) + break; + if (netif_queue_stopped(dev)) + netif_wake_queue(dev); + break; + + default: + ret = -EOPNOTSUPP; + break; + } + return ret; +} + +static int mscan_do_set_bittiming(struct net_device *dev) +{ + struct mscan_priv *priv = netdev_priv(dev); + struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; + struct can_bittiming *bt = &priv->can.bittiming; + u8 btr0, btr1; + + btr0 = BTR0_SET_BRP(bt->brp) | BTR0_SET_SJW(bt->sjw); + btr1 = (BTR1_SET_TSEG1(bt->prop_seg + bt->phase_seg1) | + BTR1_SET_TSEG2(bt->phase_seg2) | + BTR1_SET_SAM(priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)); + + dev_info(dev->dev.parent, "setting BTR0=0x%02x BTR1=0x%02x\n", + btr0, btr1); + + out_8(®s->canbtr0, btr0); + out_8(®s->canbtr1, btr1); + + return 0; +} + +static int mscan_open(struct net_device *dev) +{ + int ret; + struct mscan_priv *priv = netdev_priv(dev); + struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; + + /* common open */ + ret = open_candev(dev); + if (ret) + return ret; + + napi_enable(&priv->napi); + + ret = request_irq(dev->irq, mscan_isr, 0, dev->name, dev); + if (ret < 0) { + napi_disable(&priv->napi); + printk(KERN_ERR "%s - failed to attach interrupt\n", + dev->name); + return ret; + } + + priv->open_time = jiffies; + + out_8(®s->canctl1, in_8(®s->canctl1) & ~MSCAN_LISTEN); + + ret = mscan_start(dev); + if (ret) + return ret; + + netif_start_queue(dev); + + return 0; +} + +static int mscan_close(struct net_device *dev) +{ + struct mscan_priv *priv = netdev_priv(dev); + struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; + + netif_stop_queue(dev); + napi_disable(&priv->napi); + + out_8(®s->cantier, 0); + out_8(®s->canrier, 0); + mscan_set_mode(dev, MSCAN_INIT_MODE); + close_candev(dev); + free_irq(dev->irq, dev); + priv->open_time = 0; + + return 0; +} + +static const struct net_device_ops mscan_netdev_ops = { + .ndo_open = mscan_open, + .ndo_stop = mscan_close, + .ndo_start_xmit = mscan_start_xmit, +}; + +int register_mscandev(struct net_device *dev, int clock_src) +{ + struct mscan_priv *priv = netdev_priv(dev); + struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; + u8 ctl1; + + ctl1 = in_8(®s->canctl1); + if (clock_src) + ctl1 |= MSCAN_CLKSRC; + else + ctl1 &= ~MSCAN_CLKSRC; + + ctl1 |= MSCAN_CANE; + out_8(®s->canctl1, ctl1); + udelay(100); + + /* acceptance mask/acceptance code (accept everything) */ + out_be16(®s->canidar1_0, 0); + out_be16(®s->canidar3_2, 0); + out_be16(®s->canidar5_4, 0); + out_be16(®s->canidar7_6, 0); + + out_be16(®s->canidmr1_0, 0xffff); + out_be16(®s->canidmr3_2, 0xffff); + out_be16(®s->canidmr5_4, 0xffff); + out_be16(®s->canidmr7_6, 0xffff); + /* Two 32 bit Acceptance Filters */ + out_8(®s->canidac, MSCAN_AF_32BIT); + + mscan_set_mode(dev, MSCAN_INIT_MODE); + + return register_candev(dev); +} +EXPORT_SYMBOL_GPL(register_mscandev); + +void unregister_mscandev(struct net_device *dev) +{ + struct mscan_priv *priv = netdev_priv(dev); + struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; + mscan_set_mode(dev, MSCAN_INIT_MODE); + out_8(®s->canctl1, in_8(®s->canctl1) & ~MSCAN_CANE); + unregister_candev(dev); +} +EXPORT_SYMBOL_GPL(unregister_mscandev); + +struct net_device *alloc_mscandev(void) +{ + struct net_device *dev; + struct mscan_priv *priv; + int i; + + dev = alloc_candev(sizeof(struct mscan_priv), MSCAN_ECHO_SKB_MAX); + if (!dev) + return NULL; + priv = netdev_priv(dev); + + dev->netdev_ops = &mscan_netdev_ops; + + dev->flags |= IFF_ECHO; /* we support local echo */ + + netif_napi_add(dev, &priv->napi, mscan_rx_poll, 8); + + priv->can.bittiming_const = &mscan_bittiming_const; + priv->can.do_set_bittiming = mscan_do_set_bittiming; + priv->can.do_set_mode = mscan_do_set_mode; + + for (i = 0; i < TX_QUEUE_SIZE; i++) { + priv->tx_queue[i].id = i; + priv->tx_queue[i].mask = 1 << i; + } + + return dev; +} +EXPORT_SYMBOL_GPL(alloc_mscandev); + +MODULE_AUTHOR("Andrey Volkov <avolkov@varma-el.com>"); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("CAN port driver for a MSCAN based chips"); diff --git a/drivers/net/can/mscan/mscan.h b/drivers/net/can/mscan/mscan.h new file mode 100644 index 0000000..57820f5 --- /dev/null +++ b/drivers/net/can/mscan/mscan.h @@ -0,0 +1,262 @@ +/* + * Definitions of consts/structs to drive the Freescale MSCAN. + * + * Copyright (C) 2005-2006 Andrey Volkov <avolkov@varma-el.com>, + * Varma Electronics Oy + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the version 2 of the GNU General Public License + * as published by the Free Software Foundation + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#ifndef __MSCAN_H__ +#define __MSCAN_H__ + +#include <linux/types.h> + +/* MSCAN control register 0 (CANCTL0) bits */ +#define MSCAN_RXFRM 0x80 +#define MSCAN_RXACT 0x40 +#define MSCAN_CSWAI 0x20 +#define MSCAN_SYNCH 0x10 +#define MSCAN_TIME 0x08 +#define MSCAN_WUPE 0x04 +#define MSCAN_SLPRQ 0x02 +#define MSCAN_INITRQ 0x01 + +/* MSCAN control register 1 (CANCTL1) bits */ +#define MSCAN_CANE 0x80 +#define MSCAN_CLKSRC 0x40 +#define MSCAN_LOOPB 0x20 +#define MSCAN_LISTEN 0x10 +#define MSCAN_WUPM 0x04 +#define MSCAN_SLPAK 0x02 +#define MSCAN_INITAK 0x01 + +/* Use the MPC5200 MSCAN variant? */ +#ifdef CONFIG_PPC +#define MSCAN_FOR_MPC5200 +#endif + +#ifdef MSCAN_FOR_MPC5200 +#define MSCAN_CLKSRC_BUS 0 +#define MSCAN_CLKSRC_XTAL MSCAN_CLKSRC +#else +#define MSCAN_CLKSRC_BUS MSCAN_CLKSRC +#define MSCAN_CLKSRC_XTAL 0 +#endif + +/* MSCAN receiver flag register (CANRFLG) bits */ +#define MSCAN_WUPIF 0x80 +#define MSCAN_CSCIF 0x40 +#define MSCAN_RSTAT1 0x20 +#define MSCAN_RSTAT0 0x10 +#define MSCAN_TSTAT1 0x08 +#define MSCAN_TSTAT0 0x04 +#define MSCAN_OVRIF 0x02 +#define MSCAN_RXF 0x01 +#define MSCAN_ERR_IF (MSCAN_OVRIF | MSCAN_CSCIF) +#define MSCAN_RSTAT_MSK (MSCAN_RSTAT1 | MSCAN_RSTAT0) +#define MSCAN_TSTAT_MSK (MSCAN_TSTAT1 | MSCAN_TSTAT0) +#define MSCAN_STAT_MSK (MSCAN_RSTAT_MSK | MSCAN_TSTAT_MSK) + +#define MSCAN_STATE_BUS_OFF (MSCAN_RSTAT1 | MSCAN_RSTAT0 | \ + MSCAN_TSTAT1 | MSCAN_TSTAT0) +#define MSCAN_STATE_TX(canrflg) (((canrflg)&MSCAN_TSTAT_MSK)>>2) +#define MSCAN_STATE_RX(canrflg) (((canrflg)&MSCAN_RSTAT_MSK)>>4) +#define MSCAN_STATE_ACTIVE 0 +#define MSCAN_STATE_WARNING 1 +#define MSCAN_STATE_PASSIVE 2 +#define MSCAN_STATE_BUSOFF 3 + +/* MSCAN receiver interrupt enable register (CANRIER) bits */ +#define MSCAN_WUPIE 0x80 +#define MSCAN_CSCIE 0x40 +#define MSCAN_RSTATE1 0x20 +#define MSCAN_RSTATE0 0x10 +#define MSCAN_TSTATE1 0x08 +#define MSCAN_TSTATE0 0x04 +#define MSCAN_OVRIE 0x02 +#define MSCAN_RXFIE 0x01 + +/* MSCAN transmitter flag register (CANTFLG) bits */ +#define MSCAN_TXE2 0x04 +#define MSCAN_TXE1 0x02 +#define MSCAN_TXE0 0x01 +#define MSCAN_TXE (MSCAN_TXE2 | MSCAN_TXE1 | MSCAN_TXE0) + +/* MSCAN transmitter interrupt enable register (CANTIER) bits */ +#define MSCAN_TXIE2 0x04 +#define MSCAN_TXIE1 0x02 +#define MSCAN_TXIE0 0x01 +#define MSCAN_TXIE (MSCAN_TXIE2 | MSCAN_TXIE1 | MSCAN_TXIE0) + +/* MSCAN transmitter message abort request (CANTARQ) bits */ +#define MSCAN_ABTRQ2 0x04 +#define MSCAN_ABTRQ1 0x02 +#define MSCAN_ABTRQ0 0x01 + +/* MSCAN transmitter message abort ack (CANTAAK) bits */ +#define MSCAN_ABTAK2 0x04 +#define MSCAN_ABTAK1 0x02 +#define MSCAN_ABTAK0 0x01 + +/* MSCAN transmit buffer selection (CANTBSEL) bits */ +#define MSCAN_TX2 0x04 +#define MSCAN_TX1 0x02 +#define MSCAN_TX0 0x01 + +/* MSCAN ID acceptance control register (CANIDAC) bits */ +#define MSCAN_IDAM1 0x20 +#define MSCAN_IDAM0 0x10 +#define MSCAN_IDHIT2 0x04 +#define MSCAN_IDHIT1 0x02 +#define MSCAN_IDHIT0 0x01 + +#define MSCAN_AF_32BIT 0x00 +#define MSCAN_AF_16BIT MSCAN_IDAM0 +#define MSCAN_AF_8BIT MSCAN_IDAM1 +#define MSCAN_AF_CLOSED (MSCAN_IDAM0|MSCAN_IDAM1) +#define MSCAN_AF_MASK (~(MSCAN_IDAM0|MSCAN_IDAM1)) + +/* MSCAN Miscellaneous Register (CANMISC) bits */ +#define MSCAN_BOHOLD 0x01 + +#ifdef MSCAN_FOR_MPC5200 +#define _MSCAN_RESERVED_(n, num) u8 _res##n[num] +#define _MSCAN_RESERVED_DSR_SIZE 2 +#else +#define _MSCAN_RESERVED_(n, num) +#define _MSCAN_RESERVED_DSR_SIZE 0 +#endif + +/* Structure of the hardware registers */ +struct mscan_regs { + /* (see doc S12MSCANV3/D) MPC5200 MSCAN */ + u8 canctl0; /* + 0x00 0x00 */ + u8 canctl1; /* + 0x01 0x01 */ + _MSCAN_RESERVED_(1, 2); /* + 0x02 */ + u8 canbtr0; /* + 0x04 0x02 */ + u8 canbtr1; /* + 0x05 0x03 */ + _MSCAN_RESERVED_(2, 2); /* + 0x06 */ + u8 canrflg; /* + 0x08 0x04 */ + u8 canrier; /* + 0x09 0x05 */ + _MSCAN_RESERVED_(3, 2); /* + 0x0a */ + u8 cantflg; /* + 0x0c 0x06 */ + u8 cantier; /* + 0x0d 0x07 */ + _MSCAN_RESERVED_(4, 2); /* + 0x0e */ + u8 cantarq; /* + 0x10 0x08 */ + u8 cantaak; /* + 0x11 0x09 */ + _MSCAN_RESERVED_(5, 2); /* + 0x12 */ + u8 cantbsel; /* + 0x14 0x0a */ + u8 canidac; /* + 0x15 0x0b */ + u8 reserved; /* + 0x16 0x0c */ + _MSCAN_RESERVED_(6, 5); /* + 0x17 */ +#ifndef MSCAN_FOR_MPC5200 + u8 canmisc; /* 0x0d */ +#endif + u8 canrxerr; /* + 0x1c 0x0e */ + u8 cantxerr; /* + 0x1d 0x0f */ + _MSCAN_RESERVED_(7, 2); /* + 0x1e */ + u16 canidar1_0; /* + 0x20 0x10 */ + _MSCAN_RESERVED_(8, 2); /* + 0x22 */ + u16 canidar3_2; /* + 0x24 0x12 */ + _MSCAN_RESERVED_(9, 2); /* + 0x26 */ + u16 canidmr1_0; /* + 0x28 0x14 */ + _MSCAN_RESERVED_(10, 2); /* + 0x2a */ + u16 canidmr3_2; /* + 0x2c 0x16 */ + _MSCAN_RESERVED_(11, 2); /* + 0x2e */ + u16 canidar5_4; /* + 0x30 0x18 */ + _MSCAN_RESERVED_(12, 2); /* + 0x32 */ + u16 canidar7_6; /* + 0x34 0x1a */ + _MSCAN_RESERVED_(13, 2); /* + 0x36 */ + u16 canidmr5_4; /* + 0x38 0x1c */ + _MSCAN_RESERVED_(14, 2); /* + 0x3a */ + u16 canidmr7_6; /* + 0x3c 0x1e */ + _MSCAN_RESERVED_(15, 2); /* + 0x3e */ + struct { + u16 idr1_0; /* + 0x40 0x20 */ + _MSCAN_RESERVED_(16, 2); /* + 0x42 */ + u16 idr3_2; /* + 0x44 0x22 */ + _MSCAN_RESERVED_(17, 2); /* + 0x46 */ + u16 dsr1_0; /* + 0x48 0x24 */ + _MSCAN_RESERVED_(18, 2); /* + 0x4a */ + u16 dsr3_2; /* + 0x4c 0x26 */ + _MSCAN_RESERVED_(19, 2); /* + 0x4e */ + u16 dsr5_4; /* + 0x50 0x28 */ + _MSCAN_RESERVED_(20, 2); /* + 0x52 */ + u16 dsr7_6; /* + 0x54 0x2a */ + _MSCAN_RESERVED_(21, 2); /* + 0x56 */ + u8 dlr; /* + 0x58 0x2c */ + u8:8; /* + 0x59 0x2d */ + _MSCAN_RESERVED_(22, 2); /* + 0x5a */ + u16 time; /* + 0x5c 0x2e */ + } rx; + _MSCAN_RESERVED_(23, 2); /* + 0x5e */ + struct { + u16 idr1_0; /* + 0x60 0x30 */ + _MSCAN_RESERVED_(24, 2); /* + 0x62 */ + u16 idr3_2; /* + 0x64 0x32 */ + _MSCAN_RESERVED_(25, 2); /* + 0x66 */ + u16 dsr1_0; /* + 0x68 0x34 */ + _MSCAN_RESERVED_(26, 2); /* + 0x6a */ + u16 dsr3_2; /* + 0x6c 0x36 */ + _MSCAN_RESERVED_(27, 2); /* + 0x6e */ + u16 dsr5_4; /* + 0x70 0x38 */ + _MSCAN_RESERVED_(28, 2); /* + 0x72 */ + u16 dsr7_6; /* + 0x74 0x3a */ + _MSCAN_RESERVED_(29, 2); /* + 0x76 */ + u8 dlr; /* + 0x78 0x3c */ + u8 tbpr; /* + 0x79 0x3d */ + _MSCAN_RESERVED_(30, 2); /* + 0x7a */ + u16 time; /* + 0x7c 0x3e */ + } tx; + _MSCAN_RESERVED_(31, 2); /* + 0x7e */ +} __attribute__ ((packed)); + +#undef _MSCAN_RESERVED_ +#define MSCAN_REGION sizeof(struct mscan) + +#define TX_QUEUE_SIZE 3 + +struct tx_queue_entry { + struct list_head list; + u8 mask; + u8 id; +}; + +struct mscan_priv { + struct can_priv can; /* must be the first member */ + long open_time; + unsigned long flags; + void __iomem *reg_base; /* ioremap'ed address to registers */ + u8 shadow_statflg; + u8 shadow_canrier; + u8 cur_pri; + u8 prev_buf_id; + u8 tx_active; + + struct list_head tx_head; + struct tx_queue_entry tx_queue[TX_QUEUE_SIZE]; + struct napi_struct napi; +}; + +struct net_device *alloc_mscandev(void); +/* + * clock_src: + * 1 = The MSCAN clock source is the onchip Bus Clock. + * 0 = The MSCAN clock source is the chip Oscillator Clock. + */ +extern int register_mscandev(struct net_device *dev, int clock_src); +extern void unregister_mscandev(struct net_device *dev); + +#endif /* __MSCAN_H__ */ |