path: root/drivers/net/can/pch_can.c

/*
 * Copyright (C) 1999 - 2010 Intel Corporation.
 * Copyright (C) 2010 OKI SEMICONDUCTOR CO., LTD.
 *
 * 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; version 2 of the License.
 *
 * 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/interrupt.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/can.h>
#include <linux/can/dev.h>
#include <linux/can/error.h>

#define PCH_CTRL_INIT		BIT(0) /* The INIT bit of CANCONT register. */
#define PCH_CTRL_IE		BIT(1) /* The IE bit of CAN control register */
#define PCH_CTRL_IE_SIE_EIE	(BIT(3) | BIT(2) | BIT(1))
#define PCH_CTRL_CCE		BIT(6)
#define PCH_CTRL_OPT		BIT(7) /* The OPT bit of CANCONT register. */
#define PCH_OPT_SILENT		BIT(3) /* The Silent bit of CANOPT reg. */
#define PCH_OPT_LBACK		BIT(4) /* The LoopBack bit of CANOPT reg. */

#define PCH_CMASK_RX_TX_SET	0x00f3
#define PCH_CMASK_RX_TX_GET	0x0073
#define PCH_CMASK_ALL		0xff
#define PCH_CMASK_NEWDAT	BIT(2)
#define PCH_CMASK_CLRINTPND	BIT(3)
#define PCH_CMASK_CTRL		BIT(4)
#define PCH_CMASK_ARB		BIT(5)
#define PCH_CMASK_MASK		BIT(6)
#define PCH_CMASK_RDWR		BIT(7)
#define PCH_IF_MCONT_NEWDAT	BIT(15)
#define PCH_IF_MCONT_MSGLOST	BIT(14)
#define PCH_IF_MCONT_INTPND	BIT(13)
#define PCH_IF_MCONT_UMASK	BIT(12)
#define PCH_IF_MCONT_TXIE	BIT(11)
#define PCH_IF_MCONT_RXIE	BIT(10)
#define PCH_IF_MCONT_RMTEN	BIT(9)
#define PCH_IF_MCONT_TXRQXT	BIT(8)
#define PCH_IF_MCONT_EOB	BIT(7)
#define PCH_IF_MCONT_DLC	(BIT(0) | BIT(1) | BIT(2) | BIT(3))
#define PCH_MASK2_MDIR_MXTD	(BIT(14) | BIT(15))
#define PCH_ID2_DIR		BIT(13)
#define PCH_ID2_XTD		BIT(14)
#define PCH_ID_MSGVAL		BIT(15)
#define PCH_IF_CREQ_BUSY	BIT(15)

#define PCH_STATUS_INT		0x8000
#define PCH_RP			0x00008000
#define PCH_REC			0x00007f00
#define PCH_TEC			0x000000ff

#define PCH_TX_OK		BIT(3)
#define PCH_RX_OK		BIT(4)
#define PCH_EPASSIV		BIT(5)
#define PCH_EWARN		BIT(6)
#define PCH_BUS_OFF		BIT(7)

/* bit position of certain controller bits. */
#define PCH_BIT_BRP_SHIFT	0
#define PCH_BIT_SJW_SHIFT	6
#define PCH_BIT_TSEG1_SHIFT	8
#define PCH_BIT_TSEG2_SHIFT	12
#define PCH_BIT_BRPE_BRPE_SHIFT	6

#define PCH_MSK_BITT_BRP	0x3f
#define PCH_MSK_BRPE_BRPE	0x3c0
#define PCH_MSK_CTRL_IE_SIE_EIE	0x07
#define PCH_COUNTER_LIMIT	10

#define PCH_CAN_CLK		50000000	/* 50MHz */

/*
 * Define the number of message object.
 * PCH CAN communications are done via Message RAM.
 * The Message RAM consists of 32 message objects.
 */
#define PCH_RX_OBJ_NUM		26
#define PCH_TX_OBJ_NUM		6
#define PCH_RX_OBJ_START	1
#define PCH_RX_OBJ_END		PCH_RX_OBJ_NUM
#define PCH_TX_OBJ_START	(PCH_RX_OBJ_END + 1)
#define PCH_TX_OBJ_END		(PCH_RX_OBJ_NUM + PCH_TX_OBJ_NUM)

#define PCH_FIFO_THRESH		16

/* TxRqst2 show status of MsgObjNo.17~32 */
#define PCH_TREQ2_TX_MASK	(((1 << PCH_TX_OBJ_NUM) - 1) <<\
							(PCH_RX_OBJ_END - 16))

enum pch_ifreg {
	PCH_RX_IFREG,
	PCH_TX_IFREG,
};

enum pch_can_err {
	PCH_STUF_ERR = 1,
	PCH_FORM_ERR,
	PCH_ACK_ERR,
	PCH_BIT1_ERR,
	PCH_BIT0_ERR,
	PCH_CRC_ERR,
	PCH_LEC_ALL,
};

enum pch_can_mode {
	PCH_CAN_ENABLE,
	PCH_CAN_DISABLE,
	PCH_CAN_ALL,
	PCH_CAN_NONE,
	PCH_CAN_STOP,
	PCH_CAN_RUN,
};

struct pch_can_if_regs {
	u32 creq;
	u32 cmask;
	u32 mask1;
	u32 mask2;
	u32 id1;
	u32 id2;
	u32 mcont;
	u32 data[4];
	u32 rsv[13];
};

struct pch_can_regs {
	u32 cont;
	u32 stat;
	u32 errc;
	u32 bitt;
	u32 intr;
	u32 opt;
	u32 brpe;
	u32 reserve;
	struct pch_can_if_regs ifregs[2]; /* [0]=if1  [1]=if2 */
	u32 reserve1[8];
	u32 treq1;
	u32 treq2;
	u32 reserve2[6];
	u32 data1