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alistair23-linux/drivers/net/can/janz-ican3.c
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Janz MODULbus VMOD-ICAN3 CAN Interface Driver
*
* Copyright (c) 2010 Ira W. Snyder <iws@ovro.caltech.edu>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/netdevice.h>
#include <linux/can.h>
#include <linux/can/dev.h>
#include <linux/can/skb.h>
#include <linux/can/error.h>
#include <linux/mfd/janz.h>
#include <asm/io.h>
/* the DPM has 64k of memory, organized into 256x 256 byte pages */
#define DPM_NUM_PAGES 256
#define DPM_PAGE_SIZE 256
#define DPM_PAGE_ADDR(p) ((p) * DPM_PAGE_SIZE)
/* JANZ ICAN3 "old-style" host interface queue page numbers */
#define QUEUE_OLD_CONTROL 0
#define QUEUE_OLD_RB0 1
#define QUEUE_OLD_RB1 2
#define QUEUE_OLD_WB0 3
#define QUEUE_OLD_WB1 4
/* Janz ICAN3 "old-style" host interface control registers */
#define MSYNC_PEER 0x00 /* ICAN only */
#define MSYNC_LOCL 0x01 /* host only */
#define TARGET_RUNNING 0x02
#define FIRMWARE_STAMP 0x60 /* big endian firmware stamp */
#define MSYNC_RB0 0x01
#define MSYNC_RB1 0x02
#define MSYNC_RBLW 0x04
#define MSYNC_RB_MASK (MSYNC_RB0 | MSYNC_RB1)
#define MSYNC_WB0 0x10
#define MSYNC_WB1 0x20
#define MSYNC_WBLW 0x40
#define MSYNC_WB_MASK (MSYNC_WB0 | MSYNC_WB1)
/* Janz ICAN3 "new-style" host interface queue page numbers */
#define QUEUE_TOHOST 5
#define QUEUE_FROMHOST_MID 6
#define QUEUE_FROMHOST_HIGH 7
#define QUEUE_FROMHOST_LOW 8
/* The first free page in the DPM is #9 */
#define DPM_FREE_START 9
/* Janz ICAN3 "new-style" and "fast" host interface descriptor flags */
#define DESC_VALID 0x80
#define DESC_WRAP 0x40
#define DESC_INTERRUPT 0x20
#define DESC_IVALID 0x10
#define DESC_LEN(len) (len)
/* Janz ICAN3 Firmware Messages */
#define MSG_CONNECTI 0x02
#define MSG_DISCONNECT 0x03
#define MSG_IDVERS 0x04
#define MSG_MSGLOST 0x05
#define MSG_NEWHOSTIF 0x08
#define MSG_INQUIRY 0x0a
#define MSG_SETAFILMASK 0x10
#define MSG_INITFDPMQUEUE 0x11
#define MSG_HWCONF 0x12
#define MSG_FMSGLOST 0x15
#define MSG_CEVTIND 0x37
#define MSG_CBTRREQ 0x41
#define MSG_COFFREQ 0x42
#define MSG_CONREQ 0x43
#define MSG_CCONFREQ 0x47
#define MSG_NMTS 0xb0
#define MSG_LMTS 0xb4
/*
* Janz ICAN3 CAN Inquiry Message Types
*
* NOTE: there appears to be a firmware bug here. You must send
* NOTE: INQUIRY_STATUS and expect to receive an INQUIRY_EXTENDED
* NOTE: response. The controller never responds to a message with
* NOTE: the INQUIRY_EXTENDED subspec :(
*/
#define INQUIRY_STATUS 0x00
#define INQUIRY_TERMINATION 0x01
#define INQUIRY_EXTENDED 0x04
/* Janz ICAN3 CAN Set Acceptance Filter Mask Message Types */
#define SETAFILMASK_REJECT 0x00
#define SETAFILMASK_FASTIF 0x02
/* Janz ICAN3 CAN Hardware Configuration Message Types */
#define HWCONF_TERMINATE_ON 0x01
#define HWCONF_TERMINATE_OFF 0x00
/* Janz ICAN3 CAN Event Indication Message Types */
#define CEVTIND_EI 0x01
#define CEVTIND_DOI 0x02
#define CEVTIND_LOST 0x04
#define CEVTIND_FULL 0x08
#define CEVTIND_BEI 0x10
#define CEVTIND_CHIP_SJA1000 0x02
#define ICAN3_BUSERR_QUOTA_MAX 255
/* Janz ICAN3 CAN Frame Conversion */
#define ICAN3_SNGL 0x02
#define ICAN3_ECHO 0x10
#define ICAN3_EFF_RTR 0x40
#define ICAN3_SFF_RTR 0x10
#define ICAN3_EFF 0x80
#define ICAN3_CAN_TYPE_MASK 0x0f
#define ICAN3_CAN_TYPE_SFF 0x00
#define ICAN3_CAN_TYPE_EFF 0x01
#define ICAN3_CAN_DLC_MASK 0x0f
/* Janz ICAN3 NMTS subtypes */
#define NMTS_CREATE_NODE_REQ 0x0
#define NMTS_SLAVE_STATE_IND 0x8
#define NMTS_SLAVE_EVENT_IND 0x9
/* Janz ICAN3 LMTS subtypes */
#define LMTS_BUSON_REQ 0x0
#define LMTS_BUSOFF_REQ 0x1
#define LMTS_CAN_CONF_REQ 0x2
/* Janz ICAN3 NMTS Event indications */
#define NE_LOCAL_OCCURRED 0x3
#define NE_LOCAL_RESOLVED 0x2
#define NE_REMOTE_OCCURRED 0xc
#define NE_REMOTE_RESOLVED 0x8
/*
* SJA1000 Status and Error Register Definitions
*
* Copied from drivers/net/can/sja1000/sja1000.h
*/
/* status register content */
#define SR_BS 0x80
#define SR_ES 0x40
#define SR_TS 0x20
#define SR_RS 0x10
#define SR_TCS 0x08
#define SR_TBS 0x04
#define SR_DOS 0x02
#define SR_RBS 0x01
#define SR_CRIT (SR_BS|SR_ES)
/* ECC register */
#define ECC_SEG 0x1F
#define ECC_DIR 0x20
#define ECC_ERR 6
#define ECC_BIT 0x00
#define ECC_FORM 0x40
#define ECC_STUFF 0x80
#define ECC_MASK 0xc0
/* Number of buffers for use in the "new-style" host interface */
#define ICAN3_NEW_BUFFERS 16
/* Number of buffers for use in the "fast" host interface */
#define ICAN3_TX_BUFFERS 512
#define ICAN3_RX_BUFFERS 1024
/* SJA1000 Clock Input */
#define ICAN3_CAN_CLOCK 8000000
/* Janz ICAN3 firmware types */
enum ican3_fwtype {
ICAN3_FWTYPE_ICANOS,
ICAN3_FWTYPE_CAL_CANOPEN,
};
/* Driver Name */
#define DRV_NAME "janz-ican3"
/* DPM Control Registers -- starts at offset 0x100 in the MODULbus registers */
struct ican3_dpm_control {
/* window address register */
u8 window_address;
u8 unused1;
/*
* Read access: clear interrupt from microcontroller
* Write access: send interrupt to microcontroller
*/
u8 interrupt;
u8 unused2;
/* write-only: reset all hardware on the module */
u8 hwreset;
u8 unused3;
/* write-only: generate an interrupt to the TPU */
u8 tpuinterrupt;
};
struct ican3_dev {
/* must be the first member */
struct can_priv can;
/* CAN network device */
struct net_device *ndev;
struct napi_struct napi;
/* module number */
unsigned int num;
/* base address of registers and IRQ */
struct janz_cmodio_onboard_regs __iomem *ctrl;
struct ican3_dpm_control __iomem *dpmctrl;
void __iomem *dpm;
int irq;
/* CAN bus termination status */
struct completion termination_comp;
bool termination_enabled;
/* CAN bus error status registers */
struct completion buserror_comp;
struct can_berr_counter bec;
/* firmware type */
enum ican3_fwtype fwtype;
char fwinfo[32];
/* old and new style host interface */
unsigned int iftype;
/* queue for echo packets */
struct sk_buff_head echoq;
/*
* Any function which changes the current DPM page must hold this
* lock while it is performing data accesses. This ensures that the
* function will not be preempted and end up reading data from a
* different DPM page than it expects.
*/
spinlock_t lock;
/* new host interface */
unsigned int rx_int;
unsigned int rx_num;
unsigned int tx_num;
/* fast host interface */
unsigned int fastrx_start;
unsigned int fastrx_num;
unsigned int fasttx_start;
unsigned int fasttx_num;
/* first free DPM page */
unsigned int free_page;
};
struct ican3_msg {
u8 control;
u8 spec;
__le16 len;
u8 data[252];
};
struct ican3_new_desc {
u8 control;
u8 pointer;
};
struct ican3_fast_desc {
u8 control;
u8 command;
u8 data[14];
};
/* write to the window basic address register */
static inline void ican3_set_page(struct ican3_dev *mod, unsigned int page)
{
BUG_ON(page >= DPM_NUM_PAGES);
iowrite8(page, &mod->dpmctrl->window_address);
}
/*
* ICAN3 "old-style" host interface
*/
/*
* Receive a message from the ICAN3 "old-style" firmware interface
*
* LOCKING: must hold mod->lock
*
* returns 0 on success, -ENOMEM when no message exists
*/
static int ican3_old_recv_msg(struct ican3_dev *mod, struct ican3_msg *msg)
{
unsigned int mbox, mbox_page;
u8 locl, peer, xord;
/* get the MSYNC registers */
ican3_set_page(mod, QUEUE_OLD_CONTROL);
peer = ioread8(mod->dpm + MSYNC_PEER);
locl = ioread8(mod->dpm + MSYNC_LOCL);
xord = locl ^ peer;
if ((xord & MSYNC_RB_MASK) == 0x00) {
netdev_dbg(mod->ndev, "no mbox for reading\n");
return -ENOMEM;
}
/* find the first free mbox to read */
if ((xord & MSYNC_RB_MASK) == MSYNC_RB_MASK)
mbox = (xord & MSYNC_RBLW) ? MSYNC_RB0 : MSYNC_RB1;
else
mbox = (xord & MSYNC_RB0) ? MSYNC_RB0 : MSYNC_RB1;
/* copy the message */
mbox_page = (mbox == MSYNC_RB0) ? QUEUE_OLD_RB0 : QUEUE_OLD_RB1;
ican3_set_page(mod, mbox_page);
memcpy_fromio(msg, mod->dpm, sizeof(*msg));
/*
* notify the firmware that the read buffer is available
* for it to fill again
*/
locl ^= mbox;
ican3_set_page(mod, QUEUE_OLD_CONTROL);
iowrite8(locl, mod->dpm + MSYNC_LOCL);
return 0;
}
/*
* Send a message through the "old-style" firmware interface
*
* LOCKING: must hold mod->lock
*
* returns 0 on success, -ENOMEM when no free space exists
*/
static int ican3_old_send_msg(struct ican3_dev *mod, struct ican3_msg *msg)
{
unsigned int mbox, mbox_page;
u8 locl, peer, xord;
/* get the MSYNC registers */
ican3_set_page(mod, QUEUE_OLD_CONTROL);
peer = ioread8(mod->dpm + MSYNC_PEER);
locl = ioread8(mod->dpm + MSYNC_LOCL);
xord = locl ^ peer;
if ((xord & MSYNC_WB_MASK) == MSYNC_WB_MASK) {
netdev_err(mod->ndev, "no mbox for writing\n");
return -ENOMEM;
}
/* calculate a free mbox to use */
mbox = (xord & MSYNC_WB0) ? MSYNC_WB1 : MSYNC_WB0;
/* copy the message to the DPM */
mbox_page = (mbox == MSYNC_WB0) ? QUEUE_OLD_WB0 : QUEUE_OLD_WB1;
ican3_set_page(mod, mbox_page);
memcpy_toio(mod->dpm, msg, sizeof(*msg));
locl ^= mbox;
if (mbox == MSYNC_WB1)
locl |= MSYNC_WBLW;
ican3_set_page(mod, QUEUE_OLD_CONTROL);
iowrite8(locl, mod->dpm + MSYNC_LOCL);
return 0;
}
/*
* ICAN3 "new-style" Host Interface Setup
*/
static void ican3_init_new_host_interface(struct ican3_dev *mod)
{
struct ican3_new_desc desc;
unsigned long flags;
void __iomem *dst;
int i;
spin_lock_irqsave(&mod->lock, flags);
/* setup the internal datastructures for RX */
mod->rx_num = 0;
mod->rx_int = 0;
/* tohost queue descriptors are in page 5 */
ican3_set_page(mod, QUEUE_TOHOST);
dst = mod->dpm;
/* initialize the tohost (rx) queue descriptors: pages 9-24 */
for (i = 0; i < ICAN3_NEW_BUFFERS; i++) {
desc.control = DESC_INTERRUPT | DESC_LEN(1); /* I L=1 */
desc.pointer = mod->free_page;
/* set wrap flag on last buffer */
if (i == ICAN3_NEW_BUFFERS - 1)
desc.control |= DESC_WRAP;
memcpy_toio(dst, &desc, sizeof(desc));
dst += sizeof(desc);
mod->free_page++;
}
/* fromhost (tx) mid queue descriptors are in page 6 */
ican3_set_page(mod, QUEUE_FROMHOST_MID);
dst = mod->dpm;
/* setup the internal datastructures for TX */
mod->tx_num = 0;
/* initialize the fromhost mid queue descriptors: pages 25-40 */
for (i = 0; i < ICAN3_NEW_BUFFERS; i++) {
desc.control = DESC_VALID | DESC_LEN(1); /* V L=1 */
desc.pointer = mod->free_page;
/* set wrap flag on last buffer */
if (i == ICAN3_NEW_BUFFERS - 1)
desc.control |= DESC_WRAP;
memcpy_toio(dst, &desc, sizeof(desc));
dst += sizeof(desc);
mod->free_page++;
}
/* fromhost hi queue descriptors are in page 7 */
ican3_set_page(mod, QUEUE_FROMHOST_HIGH);
dst = mod->dpm;
/* initialize only a single buffer in the fromhost hi queue (unused) */
desc.control = DESC_VALID | DESC_WRAP | DESC_LEN(1); /* VW L=1 */
desc.pointer = mod->free_page;
memcpy_toio(dst, &desc, sizeof(desc));
mod->free_page++;
/* fromhost low queue descriptors are in page 8 */
ican3_set_page(mod, QUEUE_FROMHOST_LOW);
dst = mod->dpm;
/* initialize only a single buffer in the fromhost low queue (unused) */
desc.control = DESC_VALID | DESC_WRAP | DESC_LEN(1); /* VW L=1 */
desc.pointer = mod->free_page;
memcpy_toio(dst, &desc, sizeof(desc));
mod->free_page++;
spin_unlock_irqrestore(&mod->lock, flags);
}
/*
* ICAN3 Fast Host Interface Setup
*/
static void ican3_init_fast_host_interface(struct ican3_dev *mod)
{
struct ican3_fast_desc desc;
unsigned long flags;
unsigned int addr;
void __iomem *dst;
int i;
spin_lock_irqsave(&mod->lock, flags);
/* save the start recv page */
mod->fastrx_start = mod->free_page;
mod->fastrx_num = 0;
/* build a single fast tohost queue descriptor */
memset(&desc, 0, sizeof(desc));
desc.control = 0x00;
desc.command = 1;
/* build the tohost queue descriptor ring in memory */
addr = 0;
for (i = 0; i < ICAN3_RX_BUFFERS; i++) {
/* set the wrap bit on the last buffer */
if (i == ICAN3_RX_BUFFERS - 1)
desc.control |= DESC_WRAP;
/* switch to the correct page */
ican3_set_page(mod, mod->free_page);
/* copy the descriptor to the DPM */
dst = mod->dpm + addr;
memcpy_toio(dst, &desc, sizeof(desc));
addr += sizeof(desc);
/* move to the next page if necessary */
if (addr >= DPM_PAGE_SIZE) {
addr = 0;
mod->free_page++;
}
}
/* make sure we page-align the next queue */
if (addr != 0)
mod->free_page++;
/* save the start xmit page */
mod->fasttx_start = mod->free_page;
mod->fasttx_num = 0;
/* build a single fast fromhost queue descriptor */
memset(&desc, 0, sizeof(desc));
desc.control = DESC_VALID;
desc.command = 1;
/* build the fromhost queue descriptor ring in memory */
addr = 0;
for (i = 0; i < ICAN3_TX_BUFFERS; i++) {
/* set the wrap bit on the last buffer */
if (i == ICAN3_TX_BUFFERS - 1)
desc.control |= DESC_WRAP;
/* switch to the correct page */
ican3_set_page(mod, mod->free_page);
/* copy the descriptor to the DPM */
dst = mod->dpm + addr;
memcpy_toio(dst, &desc, sizeof(desc));
addr += sizeof(desc);
/* move to the next page if necessary */
if (addr >= DPM_PAGE_SIZE) {
addr = 0;
mod->free_page++;
}
}
spin_unlock_irqrestore(&mod->lock, flags);
}
/*
* ICAN3 "new-style" Host Interface Message Helpers
*/
/*
* LOCKING: must hold mod->lock
*/
static int ican3_new_send_msg(struct ican3_dev *mod, struct ican3_msg *msg)
{
struct ican3_new_desc desc;
void __iomem *desc_addr = mod->dpm + (mod->tx_num * sizeof(desc));
/* switch to the fromhost mid queue, and read the buffer descriptor */
ican3_set_page(mod, QUEUE_FROMHOST_MID);
memcpy_fromio(&desc, desc_addr, sizeof(desc));
if (!(desc.control & DESC_VALID)) {
netdev_dbg(mod->ndev, "%s: no free buffers\n", __func__);
return -ENOMEM;
}
/* switch to the data page, copy the data */
ican3_set_page(mod, desc.pointer);
memcpy_toio(mod->dpm, msg, sizeof(*msg));
/* switch back to the descriptor, set the valid bit, write it back */
ican3_set_page(mod, QUEUE_FROMHOST_MID);
desc.control ^= DESC_VALID;
memcpy_toio(desc_addr, &desc, sizeof(desc));
/* update the tx number */
mod->tx_num = (desc.control & DESC_WRAP) ? 0 : (mod->tx_num + 1);
return 0;
}
/*
* LOCKING: must hold mod->lock
*/
static int ican3_new_recv_msg(struct ican3_dev *mod, struct ican3_msg *msg)
{
struct ican3_new_desc desc;
void __iomem *desc_addr = mod->dpm + (mod->rx_num * sizeof(desc));
/* switch to the tohost queue, and read the buffer descriptor */
ican3_set_page(mod, QUEUE_TOHOST);
memcpy_fromio(&desc, desc_addr, sizeof(desc));
if (!(desc.control & DESC_VALID)) {
netdev_dbg(mod->ndev, "%s: no buffers to recv\n", __func__);
return -ENOMEM;
}
/* switch to the data page, copy the data */
ican3_set_page(mod, desc.pointer);
memcpy_fromio(msg, mod->dpm, sizeof(*msg));
/* switch back to the descriptor, toggle the valid bit, write it back */
ican3_set_page(mod, QUEUE_TOHOST);
desc.control ^= DESC_VALID;
memcpy_toio(desc_addr, &desc, sizeof(desc));
/* update the rx number */
mod->rx_num = (desc.control & DESC_WRAP) ? 0 : (mod->rx_num + 1);
return 0;
}
/*
* Message Send / Recv Helpers
*/
static int ican3_send_msg(struct ican3_dev *mod, struct ican3_msg *msg)
{
unsigned long flags;
int ret;
spin_lock_irqsave(&mod->lock, flags);
if (mod->iftype == 0)
ret = ican3_old_send_msg(mod, msg);
else
ret = ican3_new_send_msg(mod, msg);
spin_unlock_irqrestore(&mod->lock, flags);
return ret;
}
static int ican3_recv_msg(struct ican3_dev *mod, struct ican3_msg *msg)
{
unsigned long flags;
int ret;
spin_lock_irqsave(&mod->lock, flags);
if (mod->iftype == 0)
ret = ican3_old_recv_msg(mod, msg);
else
ret = ican3_new_recv_msg(mod, msg);
spin_unlock_irqrestore(&mod->lock, flags);
return ret;
}
/*
* Quick Pre-constructed Messages
*/
static int ican3_msg_connect(struct ican3_dev *mod)
{
struct ican3_msg msg;
memset(&msg, 0, sizeof(msg));
msg.spec = MSG_CONNECTI;
msg.len = cpu_to_le16(0);
return ican3_send_msg(mod, &msg);
}
static int ican3_msg_disconnect(struct ican3_dev *mod)
{
struct ican3_msg msg;
memset(&msg, 0, sizeof(msg));
msg.spec = MSG_DISCONNECT;
msg.len = cpu_to_le16(0);
return ican3_send_msg(mod, &msg);
}
static int ican3_msg_newhostif(struct ican3_dev *mod)
{
struct ican3_msg msg;
int ret;
memset(&msg, 0, sizeof(msg));
msg.spec = MSG_NEWHOSTIF;
msg.len = cpu_to_le16(0);
/* If we're not using the old interface, switching seems bogus */
WARN_ON(mod->iftype != 0);
ret = ican3_send_msg(mod, &msg);
if (ret)
return ret;
/* mark the module as using the new host interface */
mod->iftype = 1;
return 0;
}
static int ican3_msg_fasthostif(struct ican3_dev *mod)
{
struct ican3_msg msg;
unsigned int addr;
memset(&msg, 0, sizeof(msg));
msg.spec = MSG_INITFDPMQUEUE;
msg.len = cpu_to_le16(8);
/* write the tohost queue start address */
addr = DPM_PAGE_ADDR(mod->fastrx_start);
msg.data[0] = addr & 0xff;
msg.data[1] = (addr >> 8) & 0xff;
msg.data[2] = (addr >> 16) & 0xff;
msg.data[3] = (addr >> 24) & 0xff;
/* write the fromhost queue start address */
addr = DPM_PAGE_ADDR(mod->fasttx_start);
msg.data[4] = addr & 0xff;
msg.data[5] = (addr >> 8) & 0xff;
msg.data[6] = (addr >> 16) & 0xff;
msg.data[7] = (addr >> 24) & 0xff;
/* If we're not using the new interface yet, we cannot do this */
WARN_ON(mod->iftype != 1);
return ican3_send_msg(mod, &msg);
}
/*
* Setup the CAN filter to either accept or reject all
* messages from the CAN bus.
*/
static int ican3_set_id_filter(struct ican3_dev *mod, bool accept)
{
struct ican3_msg msg;
int ret;
/* Standard Frame Format */
memset(&msg, 0, sizeof(msg));
msg.spec = MSG_SETAFILMASK;
msg.len = cpu_to_le16(5);
msg.data[0] = 0x00; /* IDLo LSB */
msg.data[1] = 0x00; /* IDLo MSB */
msg.data[2] = 0xff; /* IDHi LSB */
msg.data[3] = 0x07; /* IDHi MSB */
/* accept all frames for fast host if, or reject all frames */
msg.data[4] = accept ? SETAFILMASK_FASTIF : SETAFILMASK_REJECT;
ret = ican3_send_msg(mod, &msg);
if (ret)
return ret;
/* Extended Frame Format */
memset(&msg, 0, sizeof(msg));
msg.spec = MSG_SETAFILMASK;
msg.len = cpu_to_le16(13);
msg.data[0] = 0; /* MUX = 0 */
msg.data[1] = 0x00; /* IDLo LSB */
msg.data[2] = 0x00;
msg.data[3] = 0x00;
msg.data[4] = 0x20; /* IDLo MSB */
msg.data[5] = 0xff; /* IDHi LSB */
msg.data[6] = 0xff;
msg.data[7] = 0xff;
msg.data[8] = 0x3f; /* IDHi MSB */
/* accept all frames for fast host if, or reject all frames */
msg.data[9] = accept ? SETAFILMASK_FASTIF : SETAFILMASK_REJECT;
return ican3_send_msg(mod, &msg);
}
/*
* Bring the CAN bus online or offline
*/
static int ican3_set_bus_state(struct ican3_dev *mod, bool on)
{
struct can_bittiming *bt = &mod->can.bittiming;
struct ican3_msg msg;
u8 btr0, btr1;
int res;
/* This algorithm was stolen from drivers/net/can/sja1000/sja1000.c */
/* The bittiming register command for the ICAN3 just sets the bit timing */
/* registers on the SJA1000 chip directly */
btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
(((bt->phase_seg2 - 1) & 0x7) << 4);
if (mod->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
btr1 |= 0x80;
if (mod->fwtype == ICAN3_FWTYPE_ICANOS) {
if (on) {
/* set bittiming */
memset(&msg, 0, sizeof(msg));
msg.spec = MSG_CBTRREQ;
msg.len = cpu_to_le16(4);
msg.data[0] = 0x00;
msg.data[1] = 0x00;
msg.data[2] = btr0;
msg.data[3] = btr1;
res = ican3_send_msg(mod, &msg);
if (res)
return res;
}
/* can-on/off request */
memset(&msg, 0, sizeof(msg));
msg.spec = on ? MSG_CONREQ : MSG_COFFREQ;
msg.len = cpu_to_le16(0);
return ican3_send_msg(mod, &msg);
} else if (mod->fwtype == ICAN3_FWTYPE_CAL_CANOPEN) {
/* bittiming + can-on/off request */
memset(&msg, 0, sizeof(msg));
msg.spec = MSG_LMTS;
if (on) {
msg.len = cpu_to_le16(4);
msg.data[0] = LMTS_BUSON_REQ;
msg.data[1] = 0;
msg.data[2] = btr0;
msg.data[3] = btr1;
} else {
msg.len = cpu_to_le16(2);
msg.data[0] = LMTS_BUSOFF_REQ;
msg.data[1] = 0;
}
res = ican3_send_msg(mod, &msg);
if (res)
return res;
if (on) {
/* create NMT Slave Node for error processing
* class 2 (with error capability, see CiA/DS203-1)
* id 1
* name locnod1 (must be exactly 7 bytes)
*/
memset(&msg, 0, sizeof(msg));
msg.spec = MSG_NMTS;
msg.len = cpu_to_le16(11);
msg.data[0] = NMTS_CREATE_NODE_REQ;
msg.data[1] = 0;
msg.data[2] = 2; /* node class */
msg.data[3] = 1; /* node id */
strcpy(msg.data + 4, "locnod1"); /* node name */
return ican3_send_msg(mod, &msg);
}
return 0;
}
return -ENOTSUPP;
}
static int ican3_set_termination(struct ican3_dev *mod, bool on)
{
struct ican3_msg msg;
memset(&msg, 0, sizeof(msg));
msg.spec = MSG_HWCONF;
msg.len = cpu_to_le16(2);
msg.data[0] = 0x00;
msg.data[1] = on ? HWCONF_TERMINATE_ON : HWCONF_TERMINATE_OFF;
return ican3_send_msg(mod, &msg);
}
static int ican3_send_inquiry(struct ican3_dev *mod, u8 subspec)
{
struct ican3_msg msg;
memset(&msg, 0, sizeof(msg));
msg.spec = MSG_INQUIRY;
msg.len = cpu_to_le16(2);
msg.data[0] = subspec;
msg.data[1] = 0x00;
return ican3_send_msg(mod, &msg);
}
static int ican3_set_buserror(struct ican3_dev *mod, u8 quota)
{
struct ican3_msg msg;
if (mod->fwtype == ICAN3_FWTYPE_ICANOS) {
memset(&msg, 0, sizeof(msg));
msg.spec = MSG_CCONFREQ;
msg.len = cpu_to_le16(2);
msg.data[0] = 0x00;
msg.data[1] = quota;
} else if (mod->fwtype == ICAN3_FWTYPE_CAL_CANOPEN) {
memset(&msg, 0, sizeof(msg));
msg.spec = MSG_LMTS;
msg.len = cpu_to_le16(4);
msg.data[0] = LMTS_CAN_CONF_REQ;
msg.data[1] = 0x00;
msg.data[2] = 0x00;
msg.data[3] = quota;
} else {
return -ENOTSUPP;
}
return ican3_send_msg(mod, &msg);
}
/*
* ICAN3 to Linux CAN Frame Conversion
*/
static void ican3_to_can_frame(struct ican3_dev *mod,
struct ican3_fast_desc *desc,
struct can_frame *cf)
{
if ((desc->command & ICAN3_CAN_TYPE_MASK) == ICAN3_CAN_TYPE_SFF) {
if (desc->data[1] & ICAN3_SFF_RTR)
cf->can_id |= CAN_RTR_FLAG;
cf->can_id |= desc->data[0] << 3;
cf->can_id |= (desc->data[1] & 0xe0) >> 5;
cf->can_dlc = get_can_dlc(desc->data[1] & ICAN3_CAN_DLC_MASK);
memcpy(cf->data, &desc->data[2], cf->can_dlc);
} else {
cf->can_dlc = get_can_dlc(desc->data[0] & ICAN3_CAN_DLC_MASK);
if (desc->data[0] & ICAN3_EFF_RTR)
cf->can_id |= CAN_RTR_FLAG;
if (desc->data[0] & ICAN3_EFF) {
cf->can_id |= CAN_EFF_FLAG;
cf->can_id |= desc->data[2] << 21; /* 28-21 */
cf->can_id |= desc->data[3] << 13; /* 20-13 */
cf->can_id |= desc->data[4] << 5; /* 12-5 */
cf->can_id |= (desc->data[5] & 0xf8) >> 3;
} else {
cf->can_id |= desc->data[2] << 3; /* 10-3 */
cf->can_id |= desc->data[3] >> 5; /* 2-0 */
}
memcpy(cf->data, &desc->data[6], cf->can_dlc);
}
}
static void can_frame_to_ican3(struct ican3_dev *mod,
struct can_frame *cf,
struct ican3_fast_desc *desc)
{
/* clear out any stale data in the descriptor */
memset(desc->data, 0, sizeof(desc->data));
/* we always use the extended format, with the ECHO flag set */
desc->command = ICAN3_CAN_TYPE_EFF;
desc->data[0] |= cf->can_dlc;
desc->data[1] |= ICAN3_ECHO;
/* support single transmission (no retries) mode */
if (mod->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
desc->data[1] |= ICAN3_SNGL;
if (cf->can_id & CAN_RTR_FLAG)
desc->data[0] |= ICAN3_EFF_RTR;
/* pack the id into the correct places */
if (cf->can_id & CAN_EFF_FLAG) {
desc->data[0] |= ICAN3_EFF;
desc->data[2] = (cf->can_id & 0x1fe00000) >> 21; /* 28-21 */
desc->data[3] = (cf->can_id & 0x001fe000) >> 13; /* 20-13 */
desc->data[4] = (cf->can_id & 0x00001fe0) >> 5; /* 12-5 */
desc->data[5] = (cf->can_id & 0x0000001f) << 3; /* 4-0 */
} else {
desc->data[2] = (cf->can_id & 0x7F8) >> 3; /* bits 10-3 */
desc->data[3] = (cf->can_id & 0x007) << 5; /* bits 2-0 */
}
/* copy the data bits into the descriptor */
memcpy(&desc->data[6], cf->data, cf->can_dlc);
}
/*
* Interrupt Handling
*/
/*
* Handle an ID + Version message response from the firmware. We never generate
* this message in production code, but it is very useful when debugging to be
* able to display this message.
*/
static void ican3_handle_idvers(struct ican3_dev *mod, struct ican3_msg *msg)
{
netdev_dbg(mod->ndev, "IDVERS response: %s\n", msg->data);
}
static void ican3_handle_msglost(struct ican3_dev *mod, struct ican3_msg *msg)
{
struct net_device *dev = mod->ndev;
struct net_device_stats *stats = &dev->stats;
struct can_frame *cf;
struct sk_buff *skb;
/*
* Report that communication messages with the microcontroller firmware
* are being lost. These are never CAN frames, so we do not generate an
* error frame for userspace
*/
if (msg->spec == MSG_MSGLOST) {
netdev_err(mod->ndev, "lost %d control messages\n", msg->data[0]);
return;
}
/*
* Oops, this indicates that we have lost messages in the fast queue,
* which are exclusively CAN messages. Our driver isn't reading CAN
* frames fast enough.
*
* We'll pretend that the SJA1000 told us that it ran out of buffer
* space, because there is not a better message for this.
*/
skb = alloc_can_err_skb(dev, &cf);
if (skb) {
cf->can_id |= CAN_ERR_CRTL;
cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
stats->rx_over_errors++;
stats->rx_errors++;
netif_rx(skb);
}
}
/*
* Handle CAN Event Indication Messages from the firmware
*
* The ICAN3 firmware provides the values of some SJA1000 registers when it
* generates this message. The code below is largely copied from the
* drivers/net/can/sja1000/sja1000.c file, and adapted as necessary
*/
static int ican3_handle_cevtind(struct ican3_dev *mod, struct ican3_msg *msg)
{
struct net_device *dev = mod->ndev;
struct net_device_stats *stats = &dev->stats;
enum can_state state = mod->can.state;
u8 isrc, ecc, status, rxerr, txerr;
struct can_frame *cf;
struct sk_buff *skb;
/* we can only handle the SJA1000 part */
if (msg->data[1] != CEVTIND_CHIP_SJA1000) {
netdev_err(mod->ndev, "unable to handle errors on non-SJA1000\n");
return -ENODEV;
}
/* check the message length for sanity */
if (le16_to_cpu(msg->len) < 6) {
netdev_err(mod->ndev, "error message too short\n");
return -EINVAL;
}
isrc = msg->data[0];
ecc = msg->data[2];
status = msg->data[3];
rxerr = msg->data[4];
txerr = msg->data[5];
/*
* This hardware lacks any support other than bus error messages to
* determine if packet transmission has failed.
*
* When TX errors happen, one echo skb needs to be dropped from the
* front of the queue.
*
* A small bit of code is duplicated here and below, to avoid error
* skb allocation when it will just be freed immediately.
*/
if (isrc == CEVTIND_BEI) {
int ret;
netdev_dbg(mod->ndev, "bus error interrupt\n");
/* TX error */
if (!(ecc & ECC_DIR)) {
kfree_skb(skb_dequeue(&mod->echoq));
stats->tx_errors++;
} else {
stats->rx_errors++;
}
/*
* The controller automatically disables bus-error interrupts
* and therefore we must re-enable them.
*/
ret = ican3_set_buserror(mod, 1);
if (ret) {
netdev_err(mod->ndev, "unable to re-enable bus-error\n");
return ret;
}
/* bus error reporting is off, return immediately */
if (!(mod->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
return 0;
}
skb = alloc_can_err_skb(dev, &cf);
if (skb == NULL)
return -ENOMEM;
/* data overrun interrupt */
if (isrc == CEVTIND_DOI || isrc == CEVTIND_LOST) {
netdev_dbg(mod->ndev, "data overrun interrupt\n");
cf->can_id |= CAN_ERR_CRTL;
cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
stats->rx_over_errors++;
stats->rx_errors++;
}
/* error warning + passive interrupt */
if (isrc == CEVTIND_EI) {
netdev_dbg(mod->ndev, "error warning + passive interrupt\n");
if (status & SR_BS) {
state = CAN_STATE_BUS_OFF;
cf->can_id |= CAN_ERR_BUSOFF;
mod->can.can_stats.bus_off++;
can_bus_off(dev);
} else if (status & SR_ES) {
if (rxerr >= 128 || txerr >= 128)
state = CAN_STATE_ERROR_PASSIVE;
else
state = CAN_STATE_ERROR_WARNING;
} else {
state = CAN_STATE_ERROR_ACTIVE;
}
}
/* bus error interrupt */
if (isrc == CEVTIND_BEI) {
mod->can.can_stats.bus_error++;
cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
switch (ecc & ECC_MASK) {
case ECC_BIT:
cf->data[2] |= CAN_ERR_PROT_BIT;
break;
case ECC_FORM:
cf->data[2] |= CAN_ERR_PROT_FORM;
break;
case ECC_STUFF:
cf->data[2] |= CAN_ERR_PROT_STUFF;
break;
default:
cf->data[3] = ecc & ECC_SEG;
break;
}
if (!(ecc & ECC_DIR))
cf->data[2] |= CAN_ERR_PROT_TX;
cf->data[6] = txerr;
cf->data[7] = rxerr;
}
if (state != mod->can.state && (state == CAN_STATE_ERROR_WARNING ||
state == CAN_STATE_ERROR_PASSIVE)) {
cf->can_id |= CAN_ERR_CRTL;
if (state == CAN_STATE_ERROR_WARNING) {
mod->can.can_stats.error_warning++;
cf->data[1] = (txerr > rxerr) ?
CAN_ERR_CRTL_TX_WARNING :
CAN_ERR_CRTL_RX_WARNING;
} else {
mod->can.can_stats.error_passive++;
cf->data[1] = (txerr > rxerr) ?
CAN_ERR_CRTL_TX_PASSIVE :
CAN_ERR_CRTL_RX_PASSIVE;
}
cf->data[6] = txerr;
cf->data[7] = rxerr;
}
mod->can.state = state;
netif_rx(skb);
return 0;
}
static void ican3_handle_inquiry(struct ican3_dev *mod, struct ican3_msg *msg)
{
switch (msg->data[0]) {
case INQUIRY_STATUS:
case INQUIRY_EXTENDED:
mod->bec.rxerr = msg->data[5];
mod->bec.txerr = msg->data[6];
complete(&mod->buserror_comp);
break;
case INQUIRY_TERMINATION:
mod->termination_enabled = msg->data[6] & HWCONF_TERMINATE_ON;
complete(&mod->termination_comp);
break;
default:
netdev_err(mod->ndev, "received an unknown inquiry response\n");
break;
}
}
/* Handle NMTS Slave Event Indication Messages from the firmware */
static void ican3_handle_nmtsind(struct ican3_dev *mod, struct ican3_msg *msg)
{
u16 subspec;
subspec = msg->data[0] + msg->data[1] * 0x100;
if (subspec == NMTS_SLAVE_EVENT_IND) {
switch (msg->data[2]) {
case NE_LOCAL_OCCURRED:
case NE_LOCAL_RESOLVED:
/* now follows the same message as Raw ICANOS CEVTIND
* shift the data at the same place and call this method
*/
le16_add_cpu(&msg->len, -3);
memmove(msg->data, msg->data + 3, le16_to_cpu(msg->len));
ican3_handle_cevtind(mod, msg);
break;
case NE_REMOTE_OCCURRED:
case NE_REMOTE_RESOLVED:
/* should not occurre, ignore */
break;
default:
netdev_warn(mod->ndev, "unknown NMTS event indication %x\n",
msg->data[2]);
break;
}
} else if (subspec == NMTS_SLAVE_STATE_IND) {
/* ignore state indications */
} else {
netdev_warn(mod->ndev, "unhandled NMTS indication %x\n",
subspec);
return;
}
}
static void ican3_handle_unknown_message(struct ican3_dev *mod,
struct ican3_msg *msg)
{
netdev_warn(mod->ndev, "received unknown message: spec 0x%.2x length %d\n",
msg->spec, le16_to_cpu(msg->len));
}
/*
* Handle a control message from the firmware
*/
static void ican3_handle_message(struct ican3_dev *mod, struct ican3_msg *msg)
{
netdev_dbg(mod->ndev, "%s: modno %d spec 0x%.2x len %d bytes\n", __func__,
mod->num, msg->spec, le16_to_cpu(msg->len));
switch (msg->spec) {
case MSG_IDVERS:
ican3_handle_idvers(mod, msg);
break;
case MSG_MSGLOST:
case MSG_FMSGLOST:
ican3_handle_msglost(mod, msg);
break;
case MSG_CEVTIND:
ican3_handle_cevtind(mod, msg);
break;
case MSG_INQUIRY:
ican3_handle_inquiry(mod, msg);
break;
case MSG_NMTS:
ican3_handle_nmtsind(mod, msg);
break;
default:
ican3_handle_unknown_message(mod, msg);
break;
}
}
/*
* The ican3 needs to store all echo skbs, and therefore cannot
* use the generic infrastructure for this.
*/
static void ican3_put_echo_skb(struct ican3_dev *mod, struct sk_buff *skb)
{
skb = can_create_echo_skb(skb);
if (!skb)
return;
/* save this skb for tx interrupt echo handling */
skb_queue_tail(&mod->echoq, skb);
}
static unsigned int ican3_get_echo_skb(struct ican3_dev *mod)
{
struct sk_buff *skb = skb_dequeue(&mod->echoq);
struct can_frame *cf;
u8 dlc;
/* this should never trigger unless there is a driver bug */
if (!skb) {
netdev_err(mod->ndev, "BUG: echo skb not occupied\n");
return 0;
}
cf = (struct can_frame *)skb->data;
dlc = cf->can_dlc;
/* check flag whether this packet has to be looped back */
if (skb->pkt_type != PACKET_LOOPBACK) {
kfree_skb(skb);
return dlc;
}
skb->protocol = htons(ETH_P_CAN);
skb->pkt_type = PACKET_BROADCAST;
skb->ip_summed = CHECKSUM_UNNECESSARY;
skb->dev = mod->ndev;
netif_receive_skb(skb);
return dlc;
}
/*
* Compare an skb with an existing echo skb
*
* This function will be used on devices which have a hardware loopback.
* On these devices, this function can be used to compare a received skb
* with the saved echo skbs so that the hardware echo skb can be dropped.
*
* Returns true if the skb's are identical, false otherwise.
*/
static bool ican3_echo_skb_matches(struct ican3_dev *mod, struct sk_buff *skb)
{
struct can_frame *cf = (struct can_frame *)skb->data;
struct sk_buff *echo_skb = skb_peek(&mod->echoq);
struct can_frame *echo_cf;
if (!echo_skb)
return false;
echo_cf = (struct can_frame *)echo_skb->data;
if (cf->can_id != echo_cf->can_id)
return false;
if (cf->can_dlc != echo_cf->can_dlc)
return false;
return memcmp(cf->data, echo_cf->data, cf->can_dlc) == 0;
}
/*
* Check that there is room in the TX ring to transmit another skb
*
* LOCKING: must hold mod->lock
*/
static bool ican3_txok(struct ican3_dev *mod)
{
struct ican3_fast_desc __iomem *desc;
u8 control;
/* check that we have echo queue space */
if (skb_queue_len(&mod->echoq) >= ICAN3_TX_BUFFERS)
return false;
/* copy the control bits of the descriptor */
ican3_set_page(mod, mod->fasttx_start + (mod->fasttx_num / 16));
desc = mod->dpm + ((mod->fasttx_num % 16) * sizeof(*desc));
control = ioread8(&desc->control);
/* if the control bits are not valid, then we have no more space */
if (!(control & DESC_VALID))
return false;
return true;
}
/*
* Receive one CAN frame from the hardware
*
* CONTEXT: must be called from user context
*/
static int ican3_recv_skb(struct ican3_dev *mod)
{
struct net_device *ndev = mod->ndev;
struct net_device_stats *stats = &ndev->stats;
struct ican3_fast_desc desc;
void __iomem *desc_addr;
struct can_frame *cf;
struct sk_buff *skb;
unsigned long flags;
spin_lock_irqsave(&mod->lock, flags);
/* copy the whole descriptor */
ican3_set_page(mod, mod->fastrx_start + (mod->fastrx_num / 16));
desc_addr = mod->dpm + ((mod->fastrx_num % 16) * sizeof(desc));
memcpy_fromio(&desc, desc_addr, sizeof(desc));
spin_unlock_irqrestore(&mod->lock, flags);
/* check that we actually have a CAN frame */
if (!(desc.control & DESC_VALID))
return -ENOBUFS;
/* allocate an skb */
skb = alloc_can_skb(ndev, &cf);
if (unlikely(skb == NULL)) {
stats->rx_dropped++;
goto err_noalloc;
}
/* convert the ICAN3 frame into Linux CAN format */
ican3_to_can_frame(mod, &desc, cf);
/*
* If this is an ECHO frame received from the hardware loopback
* feature, use the skb saved in the ECHO stack instead. This allows
* the Linux CAN core to support CAN_RAW_RECV_OWN_MSGS correctly.
*
* Since this is a confirmation of a successfully transmitted packet
* sent from this host, update the transmit statistics.
*
* Also, the netdevice queue needs to be allowed to send packets again.
*/
if (ican3_echo_skb_matches(mod, skb)) {
stats->tx_packets++;
stats->tx_bytes += ican3_get_echo_skb(mod);
kfree_skb(skb);
goto err_noalloc;
}
/* update statistics, receive the skb */
stats->rx_packets++;
stats->rx_bytes += cf->can_dlc;
netif_receive_skb(skb);
err_noalloc:
/* toggle the valid bit and return the descriptor to the ring */
desc.control ^= DESC_VALID;
spin_lock_irqsave(&mod->lock, flags);
ican3_set_page(mod, mod->fastrx_start + (mod->fastrx_num / 16));
memcpy_toio(desc_addr, &desc, 1);
/* update the next buffer pointer */
mod->fastrx_num = (desc.control & DESC_WRAP) ? 0
: (mod->fastrx_num + 1);
/* there are still more buffers to process */
spin_unlock_irqrestore(&mod->lock, flags);
return 0;
}
static int ican3_napi(struct napi_struct *napi, int budget)
{
struct ican3_dev *mod = container_of(napi, struct ican3_dev, napi);
unsigned long flags;
int received = 0;
int ret;
/* process all communication messages */
while (true) {
struct ican3_msg uninitialized_var(msg);
ret = ican3_recv_msg(mod, &msg);
if (ret)
break;
ican3_handle_message(mod, &msg);
}
/* process all CAN frames from the fast interface */
while (received < budget) {
ret = ican3_recv_skb(mod);
if (ret)
break;
received++;
}
/* We have processed all packets that the adapter had, but it
* was less than our budget, stop polling */
if (received < budget)
napi_complete_done(napi, received);
spin_lock_irqsave(&mod->lock, flags);
/* Wake up the transmit queue if necessary */
if (netif_queue_stopped(mod->ndev) && ican3_txok(mod))
netif_wake_queue(mod->ndev);
spin_unlock_irqrestore(&mod->lock, flags);
/* re-enable interrupt generation */
iowrite8(1 << mod->num, &mod->ctrl->int_enable);
return received;
}
static irqreturn_t ican3_irq(int irq, void *dev_id)
{
struct ican3_dev *mod = dev_id;
u8 stat;
/*
* The interrupt status register on this device reports interrupts
* as zeroes instead of using ones like most other devices
*/
stat = ioread8(&mod->ctrl->int_disable) & (1 << mod->num);
if (stat == (1 << mod->num))
return IRQ_NONE;
/* clear the MODULbus interrupt from the microcontroller */
ioread8(&mod->dpmctrl->interrupt);
/* disable interrupt generation, schedule the NAPI poller */
iowrite8(1 << mod->num, &mod->ctrl->int_disable);
napi_schedule(&mod->napi);
return IRQ_HANDLED;
}
/*
* Firmware reset, startup, and shutdown
*/
/*
* Reset an ICAN module to its power-on state
*
* CONTEXT: no network device registered
*/
static int ican3_reset_module(struct ican3_dev *mod)
{
unsigned long start;
u8 runold, runnew;
/* disable interrupts so no more work is scheduled */
iowrite8(1 << mod->num, &mod->ctrl->int_disable);
/* the first unallocated page in the DPM is #9 */
mod->free_page = DPM_FREE_START;
ican3_set_page(mod, QUEUE_OLD_CONTROL);
runold = ioread8(mod->dpm + TARGET_RUNNING);
/* reset the module */
iowrite8(0x00, &mod->dpmctrl->hwreset);
/* wait until the module has finished resetting and is running */
start = jiffies;
do {
ican3_set_page(mod, QUEUE_OLD_CONTROL);
runnew = ioread8(mod->dpm + TARGET_RUNNING);
if (runnew == (runold ^ 0xff))
return 0;
msleep(10);
} while (time_before(jiffies, start + HZ / 2));
netdev_err(mod->ndev, "failed to reset CAN module\n");
return -ETIMEDOUT;
}
static void ican3_shutdown_module(struct ican3_dev *mod)
{
ican3_msg_disconnect(mod);
ican3_reset_module(mod);
}
/*
* Startup an ICAN module, bringing it into fast mode
*/
static int ican3_startup_module(struct ican3_dev *mod)
{
int ret;
ret = ican3_reset_module(mod);
if (ret) {
netdev_err(mod->ndev, "unable to reset module\n");
return ret;
}
/* detect firmware */
memcpy_fromio(mod->fwinfo, mod->dpm + FIRMWARE_STAMP, sizeof(mod->fwinfo) - 1);
if (strncmp(mod->fwinfo, "JANZ-ICAN3", 10)) {
netdev_err(mod->ndev, "ICAN3 not detected (found %s)\n", mod->fwinfo);
return -ENODEV;
}
if (strstr(mod->fwinfo, "CAL/CANopen"))
mod->fwtype = ICAN3_FWTYPE_CAL_CANOPEN;
else
mod->fwtype = ICAN3_FWTYPE_ICANOS;
/* re-enable interrupts so we can send messages */
iowrite8(1 << mod->num, &mod->ctrl->int_enable);
ret = ican3_msg_connect(mod);
if (ret) {
netdev_err(mod->ndev, "unable to connect to module\n");
return ret;
}
ican3_init_new_host_interface(mod);
ret = ican3_msg_newhostif(mod);
if (ret) {
netdev_err(mod->ndev, "unable to switch to new-style interface\n");
return ret;
}
/* default to "termination on" */
ret = ican3_set_termination(mod, true);
if (ret) {
netdev_err(mod->ndev, "unable to enable termination\n");
return ret;
}
/* default to "bus errors enabled" */
ret = ican3_set_buserror(mod, 1);
if (ret) {
netdev_err(mod->ndev, "unable to set bus-error\n");
return ret;
}
ican3_init_fast_host_interface(mod);
ret = ican3_msg_fasthostif(mod);
if (ret) {
netdev_err(mod->ndev, "unable to switch to fast host interface\n");
return ret;
}
ret = ican3_set_id_filter(mod, true);
if (ret) {
netdev_err(mod->ndev, "unable to set acceptance filter\n");
return ret;
}
return 0;
}
/*
* CAN Network Device
*/
static int ican3_open(struct net_device *ndev)
{
struct ican3_dev *mod = netdev_priv(ndev);
int ret;
/* open the CAN layer */
ret = open_candev(ndev);
if (ret) {
netdev_err(mod->ndev, "unable to start CAN layer\n");
return ret;
}
/* bring the bus online */
ret = ican3_set_bus_state(mod, true);
if (ret) {
netdev_err(mod->ndev, "unable to set bus-on\n");
close_candev(ndev);
return ret;
}
/* start up the network device */
mod->can.state = CAN_STATE_ERROR_ACTIVE;
netif_start_queue(ndev);
return 0;
}
static int ican3_stop(struct net_device *ndev)
{
struct ican3_dev *mod = netdev_priv(ndev);
int ret;
/* stop the network device xmit routine */
netif_stop_queue(ndev);
mod->can.state = CAN_STATE_STOPPED;
/* bring the bus offline, stop receiving packets */
ret = ican3_set_bus_state(mod, false);
if (ret) {
netdev_err(mod->ndev, "unable to set bus-off\n");
return ret;
}
/* drop all outstanding echo skbs */
skb_queue_purge(&mod->echoq);
/* close the CAN layer */
close_candev(ndev);
return 0;
}
static netdev_tx_t ican3_xmit(struct sk_buff *skb, struct net_device *ndev)
{
struct ican3_dev *mod = netdev_priv(ndev);
struct can_frame *cf = (struct can_frame *)skb->data;
struct ican3_fast_desc desc;
void __iomem *desc_addr;
unsigned long flags;
if (can_dropped_invalid_skb(ndev, skb))
return NETDEV_TX_OK;
spin_lock_irqsave(&mod->lock, flags);
/* check that we can actually transmit */
if (!ican3_txok(mod)) {
netdev_err(mod->ndev, "BUG: no free descriptors\n");
spin_unlock_irqrestore(&mod->lock, flags);
return NETDEV_TX_BUSY;
}
/* copy the control bits of the descriptor */
ican3_set_page(mod, mod->fasttx_start + (mod->fasttx_num / 16));
desc_addr = mod->dpm + ((mod->fasttx_num % 16) * sizeof(desc));
memset(&desc, 0, sizeof(desc));
memcpy_fromio(&desc, desc_addr, 1);
/* convert the Linux CAN frame into ICAN3 format */
can_frame_to_ican3(mod, cf, &desc);
/*
* This hardware doesn't have TX-done notifications, so we'll try and
* emulate it the best we can using ECHO skbs. Add the skb to the ECHO
* stack. Upon packet reception, check if the ECHO skb and received
* skb match, and use that to wake the queue.
*/
ican3_put_echo_skb(mod, skb);
/*
* the programming manual says that you must set the IVALID bit, then
* interrupt, then set the valid bit. Quite weird, but it seems to be
* required for this to work
*/
desc.control |= DESC_IVALID;
memcpy_toio(desc_addr, &desc, sizeof(desc));
/* generate a MODULbus interrupt to the microcontroller */
iowrite8(0x01, &mod->dpmctrl->interrupt);
desc.control ^= DESC_VALID;
memcpy_toio(desc_addr, &desc, sizeof(desc));
/* update the next buffer pointer */
mod->fasttx_num = (desc.control & DESC_WRAP) ? 0
: (mod->fasttx_num + 1);
/* if there is no free descriptor space, stop the transmit queue */
if (!ican3_txok(mod))
netif_stop_queue(ndev);
spin_unlock_irqrestore(&mod->lock, flags);
return NETDEV_TX_OK;
}
static const struct net_device_ops ican3_netdev_ops = {
.ndo_open = ican3_open,
.ndo_stop = ican3_stop,
.ndo_start_xmit = ican3_xmit,
.ndo_change_mtu = can_change_mtu,
};
/*
* Low-level CAN Device
*/
/* This structure was stolen from drivers/net/can/sja1000/sja1000.c */
static const struct can_bittiming_const ican3_bittiming_const = {
.name = DRV_NAME,
.tseg1_min = 1,
.tseg1_max = 16,
.tseg2_min = 1,
.tseg2_max = 8,
.sjw_max = 4,
.brp_min = 1,
.brp_max = 64,
.brp_inc = 1,
};
static int ican3_set_mode(struct net_device *ndev, enum can_mode mode)
{
struct ican3_dev *mod = netdev_priv(ndev);
int ret;
if (mode != CAN_MODE_START)
return -ENOTSUPP;
/* bring the bus online */
ret = ican3_set_bus_state(mod, true);
if (ret) {
netdev_err(ndev, "unable to set bus-on\n");
return ret;
}
/* start up the network device */
mod->can.state = CAN_STATE_ERROR_ACTIVE;
if (netif_queue_stopped(ndev))
netif_wake_queue(ndev);
return 0;
}
static int ican3_get_berr_counter(const struct net_device *ndev,
struct can_berr_counter *bec)
{
struct ican3_dev *mod = netdev_priv(ndev);
int ret;
ret = ican3_send_inquiry(mod, INQUIRY_STATUS);
if (ret)
return ret;
if (!wait_for_completion_timeout(&mod->buserror_comp, HZ)) {
netdev_info(mod->ndev, "%s timed out\n", __func__);
return -ETIMEDOUT;
}
bec->rxerr = mod->bec.rxerr;
bec->txerr = mod->bec.txerr;
return 0;
}
/*
* Sysfs Attributes
*/
static ssize_t ican3_sysfs_show_term(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct ican3_dev *mod = netdev_priv(to_net_dev(dev));
int ret;
ret = ican3_send_inquiry(mod, INQUIRY_TERMINATION);
if (ret)
return ret;
if (!wait_for_completion_timeout(&mod->termination_comp, HZ)) {
netdev_info(mod->ndev, "%s timed out\n", __func__);
return -ETIMEDOUT;
}
return snprintf(buf, PAGE_SIZE, "%u\n", mod->termination_enabled);
}
static ssize_t ican3_sysfs_set_term(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct ican3_dev *mod = netdev_priv(to_net_dev(dev));
unsigned long enable;
int ret;
if (kstrtoul(buf, 0, &enable))
return -EINVAL;
ret = ican3_set_termination(mod, enable);
if (ret)
return ret;
return count;
}
static ssize_t ican3_sysfs_show_fwinfo(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct ican3_dev *mod = netdev_priv(to_net_dev(dev));
return scnprintf(buf, PAGE_SIZE, "%s\n", mod->fwinfo);
}
static DEVICE_ATTR(termination, 0644, ican3_sysfs_show_term,
ican3_sysfs_set_term);
static DEVICE_ATTR(fwinfo, 0444, ican3_sysfs_show_fwinfo, NULL);
static struct attribute *ican3_sysfs_attrs[] = {
&dev_attr_termination.attr,
&dev_attr_fwinfo.attr,
NULL,
};
static const struct attribute_group ican3_sysfs_attr_group = {
.attrs = ican3_sysfs_attrs,
};
/*
* PCI Subsystem
*/
static int ican3_probe(struct platform_device *pdev)
{
struct janz_platform_data *pdata;
struct net_device *ndev;
struct ican3_dev *mod;
struct resource *res;
struct device *dev;
int ret;
pdata = dev_get_platdata(&pdev->dev);
if (!pdata)
return -ENXIO;
dev_dbg(&pdev->dev, "probe: module number %d\n", pdata->modno);
/* save the struct device for printing */
dev = &pdev->dev;
/* allocate the CAN device and private data */
ndev = alloc_candev(sizeof(*mod), 0);
if (!ndev) {
dev_err(dev, "unable to allocate CANdev\n");
ret = -ENOMEM;
goto out_return;
}
platform_set_drvdata(pdev, ndev);
mod = netdev_priv(ndev);
mod->ndev = ndev;
mod->num = pdata->modno;
netif_napi_add(ndev, &mod->napi, ican3_napi, ICAN3_RX_BUFFERS);
skb_queue_head_init(&mod->echoq);
spin_lock_init(&mod->lock);
init_completion(&mod->termination_comp);
init_completion(&mod->buserror_comp);
/* setup device-specific sysfs attributes */
ndev->sysfs_groups[0] = &ican3_sysfs_attr_group;
/* the first unallocated page in the DPM is 9 */
mod->free_page = DPM_FREE_START;
ndev->netdev_ops = &ican3_netdev_ops;
ndev->flags |= IFF_ECHO;
SET_NETDEV_DEV(ndev, &pdev->dev);
mod->can.clock.freq = ICAN3_CAN_CLOCK;
mod->can.bittiming_const = &ican3_bittiming_const;
mod->can.do_set_mode = ican3_set_mode;
mod->can.do_get_berr_counter = ican3_get_berr_counter;
mod->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES
| CAN_CTRLMODE_BERR_REPORTING
| CAN_CTRLMODE_ONE_SHOT;
/* find our IRQ number */
mod->irq = platform_get_irq(pdev, 0);
if (mod->irq < 0) {
dev_err(dev, "IRQ line not found\n");
ret = -ENODEV;
goto out_free_ndev;
}
ndev->irq = mod->irq;
/* get access to the MODULbus registers for this module */
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
dev_err(dev, "MODULbus registers not found\n");
ret = -ENODEV;
goto out_free_ndev;
}
mod->dpm = ioremap(res->start, resource_size(res));
if (!mod->dpm) {
dev_err(dev, "MODULbus registers not ioremap\n");
ret = -ENOMEM;
goto out_free_ndev;
}
mod->dpmctrl = mod->dpm + DPM_PAGE_SIZE;
/* get access to the control registers for this module */
res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
if (!res) {
dev_err(dev, "CONTROL registers not found\n");
ret = -ENODEV;
goto out_iounmap_dpm;
}
mod->ctrl = ioremap(res->start, resource_size(res));
if (!mod->ctrl) {
dev_err(dev, "CONTROL registers not ioremap\n");
ret = -ENOMEM;
goto out_iounmap_dpm;
}
/* disable our IRQ, then hookup the IRQ handler */
iowrite8(1 << mod->num, &mod->ctrl->int_disable);
ret = request_irq(mod->irq, ican3_irq, IRQF_SHARED, DRV_NAME, mod);
if (ret) {
dev_err(dev, "unable to request IRQ\n");
goto out_iounmap_ctrl;
}
/* reset and initialize the CAN controller into fast mode */
napi_enable(&mod->napi);
ret = ican3_startup_module(mod);
if (ret) {
dev_err(dev, "%s: unable to start CANdev\n", __func__);
goto out_free_irq;
}
/* register with the Linux CAN layer */
ret = register_candev(ndev);
if (ret) {
dev_err(dev, "%s: unable to register CANdev\n", __func__);
goto out_free_irq;
}
netdev_info(mod->ndev, "module %d: registered CAN device\n", pdata->modno);
return 0;
out_free_irq:
napi_disable(&mod->napi);
iowrite8(1 << mod->num, &mod->ctrl->int_disable);
free_irq(mod->irq, mod);
out_iounmap_ctrl:
iounmap(mod->ctrl);
out_iounmap_dpm:
iounmap(mod->dpm);
out_free_ndev:
free_candev(ndev);
out_return:
return ret;
}
static int ican3_remove(struct platform_device *pdev)
{
struct net_device *ndev = platform_get_drvdata(pdev);
struct ican3_dev *mod = netdev_priv(ndev);
/* unregister the netdevice, stop interrupts */
unregister_netdev(ndev);
napi_disable(&mod->napi);
iowrite8(1 << mod->num, &mod->ctrl->int_disable);
free_irq(mod->irq, mod);
/* put the module into reset */
ican3_shutdown_module(mod);
/* unmap all registers */
iounmap(mod->ctrl);
iounmap(mod->dpm);
free_candev(ndev);
return 0;
}
static struct platform_driver ican3_driver = {
.driver = {
.name = DRV_NAME,
},
.probe = ican3_probe,
.remove = ican3_remove,
};
module_platform_driver(ican3_driver);
MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>");
MODULE_DESCRIPTION("Janz MODULbus VMOD-ICAN3 Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:janz-ican3");
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