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linux/drivers/net/can/flexcan.c

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// SPDX-License-Identifier: GPL-2.0
//
// flexcan.c - FLEXCAN CAN controller driver
//
// Copyright (c) 2005-2006 Varma Electronics Oy
// Copyright (c) 2009 Sascha Hauer, Pengutronix
// Copyright (c) 2010-2017 Pengutronix, Marc Kleine-Budde <kernel@pengutronix.de>
// Copyright (c) 2014 David Jander, Protonic Holland
//
// Based on code originally by Andrey Volkov <avolkov@varma-el.com>
#include <linux/netdevice.h>
#include <linux/can.h>
#include <linux/can/dev.h>
#include <linux/can/error.h>
#include <linux/can/led.h>
#include <linux/can/rx-offload.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include <linux/regmap.h>
#define DRV_NAME "flexcan"
/* 8 for RX fifo and 2 error handling */
#define FLEXCAN_NAPI_WEIGHT (8 + 2)
/* FLEXCAN module configuration register (CANMCR) bits */
#define FLEXCAN_MCR_MDIS BIT(31)
#define FLEXCAN_MCR_FRZ BIT(30)
#define FLEXCAN_MCR_FEN BIT(29)
#define FLEXCAN_MCR_HALT BIT(28)
#define FLEXCAN_MCR_NOT_RDY BIT(27)
#define FLEXCAN_MCR_WAK_MSK BIT(26)
#define FLEXCAN_MCR_SOFTRST BIT(25)
#define FLEXCAN_MCR_FRZ_ACK BIT(24)
#define FLEXCAN_MCR_SUPV BIT(23)
#define FLEXCAN_MCR_SLF_WAK BIT(22)
#define FLEXCAN_MCR_WRN_EN BIT(21)
#define FLEXCAN_MCR_LPM_ACK BIT(20)
#define FLEXCAN_MCR_WAK_SRC BIT(19)
#define FLEXCAN_MCR_DOZE BIT(18)
#define FLEXCAN_MCR_SRX_DIS BIT(17)
#define FLEXCAN_MCR_IRMQ BIT(16)
#define FLEXCAN_MCR_LPRIO_EN BIT(13)
#define FLEXCAN_MCR_AEN BIT(12)
/* MCR_MAXMB: maximum used MBs is MAXMB + 1 */
#define FLEXCAN_MCR_MAXMB(x) ((x) & 0x7f)
#define FLEXCAN_MCR_IDAM_A (0x0 << 8)
#define FLEXCAN_MCR_IDAM_B (0x1 << 8)
#define FLEXCAN_MCR_IDAM_C (0x2 << 8)
#define FLEXCAN_MCR_IDAM_D (0x3 << 8)
/* FLEXCAN control register (CANCTRL) bits */
#define FLEXCAN_CTRL_PRESDIV(x) (((x) & 0xff) << 24)
#define FLEXCAN_CTRL_RJW(x) (((x) & 0x03) << 22)
#define FLEXCAN_CTRL_PSEG1(x) (((x) & 0x07) << 19)
#define FLEXCAN_CTRL_PSEG2(x) (((x) & 0x07) << 16)
#define FLEXCAN_CTRL_BOFF_MSK BIT(15)
#define FLEXCAN_CTRL_ERR_MSK BIT(14)
#define FLEXCAN_CTRL_CLK_SRC BIT(13)
#define FLEXCAN_CTRL_LPB BIT(12)
#define FLEXCAN_CTRL_TWRN_MSK BIT(11)
#define FLEXCAN_CTRL_RWRN_MSK BIT(10)
#define FLEXCAN_CTRL_SMP BIT(7)
#define FLEXCAN_CTRL_BOFF_REC BIT(6)
#define FLEXCAN_CTRL_TSYN BIT(5)
#define FLEXCAN_CTRL_LBUF BIT(4)
#define FLEXCAN_CTRL_LOM BIT(3)
#define FLEXCAN_CTRL_PROPSEG(x) ((x) & 0x07)
#define FLEXCAN_CTRL_ERR_BUS (FLEXCAN_CTRL_ERR_MSK)
#define FLEXCAN_CTRL_ERR_STATE \
(FLEXCAN_CTRL_TWRN_MSK | FLEXCAN_CTRL_RWRN_MSK | \
FLEXCAN_CTRL_BOFF_MSK)
#define FLEXCAN_CTRL_ERR_ALL \
(FLEXCAN_CTRL_ERR_BUS | FLEXCAN_CTRL_ERR_STATE)
/* FLEXCAN control register 2 (CTRL2) bits */
#define FLEXCAN_CTRL2_ECRWRE BIT(29)
#define FLEXCAN_CTRL2_WRMFRZ BIT(28)
#define FLEXCAN_CTRL2_RFFN(x) (((x) & 0x0f) << 24)
#define FLEXCAN_CTRL2_TASD(x) (((x) & 0x1f) << 19)
#define FLEXCAN_CTRL2_MRP BIT(18)
#define FLEXCAN_CTRL2_RRS BIT(17)
#define FLEXCAN_CTRL2_EACEN BIT(16)
/* FLEXCAN memory error control register (MECR) bits */
#define FLEXCAN_MECR_ECRWRDIS BIT(31)
#define FLEXCAN_MECR_HANCEI_MSK BIT(19)
#define FLEXCAN_MECR_FANCEI_MSK BIT(18)
#define FLEXCAN_MECR_CEI_MSK BIT(16)
#define FLEXCAN_MECR_HAERRIE BIT(15)
#define FLEXCAN_MECR_FAERRIE BIT(14)
#define FLEXCAN_MECR_EXTERRIE BIT(13)
#define FLEXCAN_MECR_RERRDIS BIT(9)
#define FLEXCAN_MECR_ECCDIS BIT(8)
#define FLEXCAN_MECR_NCEFAFRZ BIT(7)
/* FLEXCAN error and status register (ESR) bits */
#define FLEXCAN_ESR_TWRN_INT BIT(17)
#define FLEXCAN_ESR_RWRN_INT BIT(16)
#define FLEXCAN_ESR_BIT1_ERR BIT(15)
#define FLEXCAN_ESR_BIT0_ERR BIT(14)
#define FLEXCAN_ESR_ACK_ERR BIT(13)
#define FLEXCAN_ESR_CRC_ERR BIT(12)
#define FLEXCAN_ESR_FRM_ERR BIT(11)
#define FLEXCAN_ESR_STF_ERR BIT(10)
#define FLEXCAN_ESR_TX_WRN BIT(9)
#define FLEXCAN_ESR_RX_WRN BIT(8)
#define FLEXCAN_ESR_IDLE BIT(7)
#define FLEXCAN_ESR_TXRX BIT(6)
#define FLEXCAN_EST_FLT_CONF_SHIFT (4)
#define FLEXCAN_ESR_FLT_CONF_MASK (0x3 << FLEXCAN_EST_FLT_CONF_SHIFT)
#define FLEXCAN_ESR_FLT_CONF_ACTIVE (0x0 << FLEXCAN_EST_FLT_CONF_SHIFT)
#define FLEXCAN_ESR_FLT_CONF_PASSIVE (0x1 << FLEXCAN_EST_FLT_CONF_SHIFT)
#define FLEXCAN_ESR_BOFF_INT BIT(2)
#define FLEXCAN_ESR_ERR_INT BIT(1)
#define FLEXCAN_ESR_WAK_INT BIT(0)
#define FLEXCAN_ESR_ERR_BUS \
(FLEXCAN_ESR_BIT1_ERR | FLEXCAN_ESR_BIT0_ERR | \
FLEXCAN_ESR_ACK_ERR | FLEXCAN_ESR_CRC_ERR | \
FLEXCAN_ESR_FRM_ERR | FLEXCAN_ESR_STF_ERR)
#define FLEXCAN_ESR_ERR_STATE \
(FLEXCAN_ESR_TWRN_INT | FLEXCAN_ESR_RWRN_INT | FLEXCAN_ESR_BOFF_INT)
#define FLEXCAN_ESR_ERR_ALL \
(FLEXCAN_ESR_ERR_BUS | FLEXCAN_ESR_ERR_STATE)
#define FLEXCAN_ESR_ALL_INT \
(FLEXCAN_ESR_TWRN_INT | FLEXCAN_ESR_RWRN_INT | \
FLEXCAN_ESR_BOFF_INT | FLEXCAN_ESR_ERR_INT | \
FLEXCAN_ESR_WAK_INT)
/* FLEXCAN interrupt flag register (IFLAG) bits */
/* Errata ERR005829 step7: Reserve first valid MB */
#define FLEXCAN_TX_MB_RESERVED_OFF_FIFO 8
#define FLEXCAN_TX_MB_RESERVED_OFF_TIMESTAMP 0
#define FLEXCAN_RX_MB_OFF_TIMESTAMP_FIRST (FLEXCAN_TX_MB_RESERVED_OFF_TIMESTAMP + 1)
#define FLEXCAN_IFLAG_MB(x) BIT((x) & 0x1f)
#define FLEXCAN_IFLAG_RX_FIFO_OVERFLOW BIT(7)
#define FLEXCAN_IFLAG_RX_FIFO_WARN BIT(6)
#define FLEXCAN_IFLAG_RX_FIFO_AVAILABLE BIT(5)
/* FLEXCAN message buffers */
#define FLEXCAN_MB_CODE_MASK (0xf << 24)
#define FLEXCAN_MB_CODE_RX_BUSY_BIT (0x1 << 24)
#define FLEXCAN_MB_CODE_RX_INACTIVE (0x0 << 24)
#define FLEXCAN_MB_CODE_RX_EMPTY (0x4 << 24)
#define FLEXCAN_MB_CODE_RX_FULL (0x2 << 24)
#define FLEXCAN_MB_CODE_RX_OVERRUN (0x6 << 24)
#define FLEXCAN_MB_CODE_RX_RANSWER (0xa << 24)
#define FLEXCAN_MB_CODE_TX_INACTIVE (0x8 << 24)
#define FLEXCAN_MB_CODE_TX_ABORT (0x9 << 24)
#define FLEXCAN_MB_CODE_TX_DATA (0xc << 24)
#define FLEXCAN_MB_CODE_TX_TANSWER (0xe << 24)
#define FLEXCAN_MB_CNT_SRR BIT(22)
#define FLEXCAN_MB_CNT_IDE BIT(21)
#define FLEXCAN_MB_CNT_RTR BIT(20)
#define FLEXCAN_MB_CNT_LENGTH(x) (((x) & 0xf) << 16)
#define FLEXCAN_MB_CNT_TIMESTAMP(x) ((x) & 0xffff)
#define FLEXCAN_TIMEOUT_US (250)
/* FLEXCAN hardware feature flags
*
* Below is some version info we got:
* SOC Version IP-Version Glitch- [TR]WRN_INT IRQ Err Memory err RTR re-
* Filter? connected? Passive detection ception in MB
* MX25 FlexCAN2 03.00.00.00 no no no no no
* MX28 FlexCAN2 03.00.04.00 yes yes no no no
* MX35 FlexCAN2 03.00.00.00 no no no no no
* MX53 FlexCAN2 03.00.00.00 yes no no no no
* MX6s FlexCAN3 10.00.12.00 yes yes no no yes
* VF610 FlexCAN3 ? no yes no yes yes?
* LS1021A FlexCAN2 03.00.04.00 no yes no no yes
*
* Some SOCs do not have the RX_WARN & TX_WARN interrupt line connected.
*/
#define FLEXCAN_QUIRK_BROKEN_WERR_STATE BIT(1) /* [TR]WRN_INT not connected */
#define FLEXCAN_QUIRK_DISABLE_RXFG BIT(2) /* Disable RX FIFO Global mask */
#define FLEXCAN_QUIRK_ENABLE_EACEN_RRS BIT(3) /* Enable EACEN and RRS bit in ctrl2 */
#define FLEXCAN_QUIRK_DISABLE_MECR BIT(4) /* Disable Memory error detection */
#define FLEXCAN_QUIRK_USE_OFF_TIMESTAMP BIT(5) /* Use timestamp based offloading */
#define FLEXCAN_QUIRK_BROKEN_PERR_STATE BIT(6) /* No interrupt for error passive */
#define FLEXCAN_QUIRK_DEFAULT_BIG_ENDIAN BIT(7) /* default to BE register access */
#define FLEXCAN_QUIRK_SETUP_STOP_MODE BIT(8) /* Setup stop mode to support wakeup */
/* Structure of the message buffer */
struct flexcan_mb {
u32 can_ctrl;
u32 can_id;
u32 data[];
};
/* Structure of the hardware registers */
struct flexcan_regs {
u32 mcr; /* 0x00 */
u32 ctrl; /* 0x04 */
u32 timer; /* 0x08 */
u32 _reserved1; /* 0x0c */
u32 rxgmask; /* 0x10 */
u32 rx14mask; /* 0x14 */
u32 rx15mask; /* 0x18 */
u32 ecr; /* 0x1c */
u32 esr; /* 0x20 */
u32 imask2; /* 0x24 */
u32 imask1; /* 0x28 */
u32 iflag2; /* 0x2c */
u32 iflag1; /* 0x30 */
union { /* 0x34 */
u32 gfwr_mx28; /* MX28, MX53 */
u32 ctrl2; /* MX6, VF610 */
};
u32 esr2; /* 0x38 */
u32 imeur; /* 0x3c */
u32 lrfr; /* 0x40 */
u32 crcr; /* 0x44 */
u32 rxfgmask; /* 0x48 */
u32 rxfir; /* 0x4c */
u32 _reserved3[12]; /* 0x50 */
u8 mb[2][512]; /* 0x80 */
/* FIFO-mode:
* MB
* 0x080...0x08f 0 RX message buffer
* 0x090...0x0df 1-5 reserverd
* 0x0e0...0x0ff 6-7 8 entry ID table
* (mx25, mx28, mx35, mx53)
* 0x0e0...0x2df 6-7..37 8..128 entry ID table
* size conf'ed via ctrl2::RFFN
* (mx6, vf610)
*/
u32 _reserved4[256]; /* 0x480 */
u32 rximr[64]; /* 0x880 */
u32 _reserved5[24]; /* 0x980 */
u32 gfwr_mx6; /* 0x9e0 - MX6 */
u32 _reserved6[63]; /* 0x9e4 */
u32 mecr; /* 0xae0 */
u32 erriar; /* 0xae4 */
u32 erridpr; /* 0xae8 */
u32 errippr; /* 0xaec */
u32 rerrar; /* 0xaf0 */
u32 rerrdr; /* 0xaf4 */
u32 rerrsynr; /* 0xaf8 */
u32 errsr; /* 0xafc */
};
struct flexcan_devtype_data {
u32 quirks; /* quirks needed for different IP cores */
};
struct flexcan_stop_mode {
struct regmap *gpr;
u8 req_gpr;
u8 req_bit;
u8 ack_gpr;
u8 ack_bit;
};
struct flexcan_priv {
struct can_priv can;
struct can_rx_offload offload;
struct flexcan_regs __iomem *regs;
struct flexcan_mb __iomem *tx_mb;
struct flexcan_mb __iomem *tx_mb_reserved;
u8 tx_mb_idx;
u8 mb_count;
u8 mb_size;
u32 reg_ctrl_default;
u32 reg_imask1_default;
u32 reg_imask2_default;
struct clk *clk_ipg;
struct clk *clk_per;
const struct flexcan_devtype_data *devtype_data;
struct regulator *reg_xceiver;
struct flexcan_stop_mode stm;
/* Read and Write APIs */
u32 (*read)(void __iomem *addr);
void (*write)(u32 val, void __iomem *addr);
};
static const struct flexcan_devtype_data fsl_p1010_devtype_data = {
.quirks = FLEXCAN_QUIRK_BROKEN_WERR_STATE |
FLEXCAN_QUIRK_BROKEN_PERR_STATE |
FLEXCAN_QUIRK_DEFAULT_BIG_ENDIAN,
};
static const struct flexcan_devtype_data fsl_imx25_devtype_data = {
.quirks = FLEXCAN_QUIRK_BROKEN_WERR_STATE |
FLEXCAN_QUIRK_BROKEN_PERR_STATE,
};
static const struct flexcan_devtype_data fsl_imx28_devtype_data = {
.quirks = FLEXCAN_QUIRK_BROKEN_PERR_STATE,
};
static const struct flexcan_devtype_data fsl_imx6q_devtype_data = {
.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
FLEXCAN_QUIRK_USE_OFF_TIMESTAMP | FLEXCAN_QUIRK_BROKEN_PERR_STATE |
FLEXCAN_QUIRK_SETUP_STOP_MODE,
};
static const struct flexcan_devtype_data fsl_vf610_devtype_data = {
.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
FLEXCAN_QUIRK_DISABLE_MECR | FLEXCAN_QUIRK_USE_OFF_TIMESTAMP |
FLEXCAN_QUIRK_BROKEN_PERR_STATE,
};
static const struct flexcan_devtype_data fsl_ls1021a_r2_devtype_data = {
.quirks = FLEXCAN_QUIRK_DISABLE_RXFG | FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
FLEXCAN_QUIRK_DISABLE_MECR | FLEXCAN_QUIRK_BROKEN_PERR_STATE |
FLEXCAN_QUIRK_USE_OFF_TIMESTAMP,
};
static const struct can_bittiming_const flexcan_bittiming_const = {
.name = DRV_NAME,
.tseg1_min = 4,
.tseg1_max = 16,
.tseg2_min = 2,
.tseg2_max = 8,
.sjw_max = 4,
.brp_min = 1,
.brp_max = 256,
.brp_inc = 1,
};
/* FlexCAN module is essentially modelled as a little-endian IP in most
* SoCs, i.e the registers as well as the message buffer areas are
* implemented in a little-endian fashion.
*
* However there are some SoCs (e.g. LS1021A) which implement the FlexCAN
* module in a big-endian fashion (i.e the registers as well as the
* message buffer areas are implemented in a big-endian way).
*
* In addition, the FlexCAN module can be found on SoCs having ARM or
* PPC cores. So, we need to abstract off the register read/write
* functions, ensuring that these cater to all the combinations of module
* endianness and underlying CPU endianness.
*/
static inline u32 flexcan_read_be(void __iomem *addr)
{
return ioread32be(addr);
}
static inline void flexcan_write_be(u32 val, void __iomem *addr)
{
iowrite32be(val, addr);
}
static inline u32 flexcan_read_le(void __iomem *addr)
{
return ioread32(addr);
}
static inline void flexcan_write_le(u32 val, void __iomem *addr)
{
iowrite32(val, addr);
}
static struct flexcan_mb __iomem *flexcan_get_mb(const struct flexcan_priv *priv,
u8 mb_index)
{
u8 bank_size;
bool bank;
if (WARN_ON(mb_index >= priv->mb_count))
return NULL;
bank_size = sizeof(priv->regs->mb[0]) / priv->mb_size;
bank = mb_index >= bank_size;
if (bank)
mb_index -= bank_size;
return (struct flexcan_mb __iomem *)
(&priv->regs->mb[bank][priv->mb_size * mb_index]);
}
static void flexcan_enable_wakeup_irq(struct flexcan_priv *priv, bool enable)
{
struct flexcan_regs __iomem *regs = priv->regs;
u32 reg_mcr;
reg_mcr = priv->read(&regs->mcr);
if (enable)
reg_mcr |= FLEXCAN_MCR_WAK_MSK;
else
reg_mcr &= ~FLEXCAN_MCR_WAK_MSK;
priv->write(reg_mcr, &regs->mcr);
}
static inline void flexcan_enter_stop_mode(struct flexcan_priv *priv)
{
struct flexcan_regs __iomem *regs = priv->regs;
u32 reg_mcr;
reg_mcr = priv->read(&regs->mcr);
reg_mcr |= FLEXCAN_MCR_SLF_WAK;
priv->write(reg_mcr, &regs->mcr);
/* enable stop request */
regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr,
1 << priv->stm.req_bit, 1 << priv->stm.req_bit);
}
static inline void flexcan_exit_stop_mode(struct flexcan_priv *priv)
{
struct flexcan_regs __iomem *regs = priv->regs;
u32 reg_mcr;
/* remove stop request */
regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr,
1 << priv->stm.req_bit, 0);
reg_mcr = priv->read(&regs->mcr);
reg_mcr &= ~FLEXCAN_MCR_SLF_WAK;
priv->write(reg_mcr, &regs->mcr);
}
static inline void flexcan_error_irq_enable(const struct flexcan_priv *priv)
{
struct flexcan_regs __iomem *regs = priv->regs;
u32 reg_ctrl = (priv->reg_ctrl_default | FLEXCAN_CTRL_ERR_MSK);
priv->write(reg_ctrl, &regs->ctrl);
}
static inline void flexcan_error_irq_disable(const struct flexcan_priv *priv)
{
struct flexcan_regs __iomem *regs = priv->regs;
u32 reg_ctrl = (priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_MSK);
priv->write(reg_ctrl, &regs->ctrl);
}
static inline int flexcan_transceiver_enable(const struct flexcan_priv *priv)
{
if (!priv->reg_xceiver)
return 0;
return regulator_enable(priv->reg_xceiver);
}
static inline int flexcan_transceiver_disable(const struct flexcan_priv *priv)
{
if (!priv->reg_xceiver)
return 0;
return regulator_disable(priv->reg_xceiver);
}
static int flexcan_chip_enable(struct flexcan_priv *priv)
{
struct flexcan_regs __iomem *regs = priv->regs;
unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
u32 reg;
reg = priv->read(&regs->mcr);
reg &= ~FLEXCAN_MCR_MDIS;
priv->write(reg, &regs->mcr);
while (timeout-- && (priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
udelay(10);
if (priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK)
return -ETIMEDOUT;
return 0;
}
static int flexcan_chip_disable(struct flexcan_priv *priv)
{
struct flexcan_regs __iomem *regs = priv->regs;
unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
u32 reg;
reg = priv->read(&regs->mcr);
reg |= FLEXCAN_MCR_MDIS;
priv->write(reg, &regs->mcr);
while (timeout-- && !(priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
udelay(10);
if (!(priv->read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
return -ETIMEDOUT;
return 0;
}
static int flexcan_chip_freeze(struct flexcan_priv *priv)
{
struct flexcan_regs __iomem *regs = priv->regs;
unsigned int timeout = 1000 * 1000 * 10 / priv->can.bittiming.bitrate;
u32 reg;
reg = priv->read(&regs->mcr);
reg |= FLEXCAN_MCR_HALT;
priv->write(reg, &regs->mcr);
while (timeout-- && !(priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
udelay(100);
if (!(priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
return -ETIMEDOUT;
return 0;
}
static int flexcan_chip_unfreeze(struct flexcan_priv *priv)
{
struct flexcan_regs __iomem *regs = priv->regs;
unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
u32 reg;
reg = priv->read(&regs->mcr);
reg &= ~FLEXCAN_MCR_HALT;
priv->write(reg, &regs->mcr);
while (timeout-- && (priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
udelay(10);
if (priv->read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK)
return -ETIMEDOUT;
return 0;
}
static int flexcan_chip_softreset(struct flexcan_priv *priv)
{
struct flexcan_regs __iomem *regs = priv->regs;
unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
priv->write(FLEXCAN_MCR_SOFTRST, &regs->mcr);
while (timeout-- && (priv->read(&regs->mcr) & FLEXCAN_MCR_SOFTRST))
udelay(10);
if (priv->read(&regs->mcr) & FLEXCAN_MCR_SOFTRST)
return -ETIMEDOUT;
return 0;
}
static int __flexcan_get_berr_counter(const struct net_device *dev,
struct can_berr_counter *bec)
{
const struct flexcan_priv *priv = netdev_priv(dev);
struct flexcan_regs __iomem *regs = priv->regs;
u32 reg = priv->read(&regs->ecr);
bec->txerr = (reg >> 0) & 0xff;
bec->rxerr = (reg >> 8) & 0xff;
return 0;
}
static int flexcan_get_berr_counter(const struct net_device *dev,
struct can_berr_counter *bec)
{
const struct flexcan_priv *priv = netdev_priv(dev);
int err;
err = clk_prepare_enable(priv->clk_ipg);
if (err)
return err;
err = clk_prepare_enable(priv->clk_per);
if (err)
goto out_disable_ipg;
err = __flexcan_get_berr_counter(dev, bec);
clk_disable_unprepare(priv->clk_per);
out_disable_ipg:
clk_disable_unprepare(priv->clk_ipg);
return err;
}
static netdev_tx_t flexcan_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
const struct flexcan_priv *priv = netdev_priv(dev);
struct can_frame *cf = (struct can_frame *)skb->data;
u32 can_id;
u32 data;
u32 ctrl = FLEXCAN_MB_CODE_TX_DATA | (cf->can_dlc << 16);
int i;
if (can_dropped_invalid_skb(dev, skb))
return NETDEV_TX_OK;
netif_stop_queue(dev);
if (cf->can_id & CAN_EFF_FLAG) {
can_id = cf->can_id & CAN_EFF_MASK;
ctrl |= FLEXCAN_MB_CNT_IDE | FLEXCAN_MB_CNT_SRR;
} else {
can_id = (cf->can_id & CAN_SFF_MASK) << 18;
}
if (cf->can_id & CAN_RTR_FLAG)
ctrl |= FLEXCAN_MB_CNT_RTR;
for (i = 0; i < cf->can_dlc; i += sizeof(u32)) {
data = be32_to_cpup((__be32 *)&cf->data[i]);
priv->write(data, &priv->tx_mb->data[i / sizeof(u32)]);
}
can_put_echo_skb(skb, dev, 0);
priv->write(can_id, &priv->tx_mb->can_id);
priv->write(ctrl, &priv->tx_mb->can_ctrl);
/* Errata ERR005829 step8:
* Write twice INACTIVE(0x8) code to first MB.
*/
priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
&priv->tx_mb_reserved->can_ctrl);
priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
&priv->tx_mb_reserved->can_ctrl);
return NETDEV_TX_OK;
}
static void flexcan_irq_bus_err(struct net_device *dev, u32 reg_esr)
{
struct flexcan_priv *priv = netdev_priv(dev);
struct flexcan_regs __iomem *regs = priv->regs;
struct sk_buff *skb;
struct can_frame *cf;
bool rx_errors = false, tx_errors = false;
u32 timestamp;
timestamp = priv->read(&regs->timer) << 16;
skb = alloc_can_err_skb(dev, &cf);
if (unlikely(!skb))
return;
cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
if (reg_esr & FLEXCAN_ESR_BIT1_ERR) {
netdev_dbg(dev, "BIT1_ERR irq\n");
cf->data[2] |= CAN_ERR_PROT_BIT1;
tx_errors = true;
}
if (reg_esr & FLEXCAN_ESR_BIT0_ERR) {
netdev_dbg(dev, "BIT0_ERR irq\n");
cf->data[2] |= CAN_ERR_PROT_BIT0;
tx_errors = true;
}
if (reg_esr & FLEXCAN_ESR_ACK_ERR) {
netdev_dbg(dev, "ACK_ERR irq\n");
cf->can_id |= CAN_ERR_ACK;
cf->data[3] = CAN_ERR_PROT_LOC_ACK;
tx_errors = true;
}
if (reg_esr & FLEXCAN_ESR_CRC_ERR) {
netdev_dbg(dev, "CRC_ERR irq\n");
cf->data[2] |= CAN_ERR_PROT_BIT;
cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
rx_errors = true;
}
if (reg_esr & FLEXCAN_ESR_FRM_ERR) {
netdev_dbg(dev, "FRM_ERR irq\n");
cf->data[2] |= CAN_ERR_PROT_FORM;
rx_errors = true;
}
if (reg_esr & FLEXCAN_ESR_STF_ERR) {
netdev_dbg(dev, "STF_ERR irq\n");
cf->data[2] |= CAN_ERR_PROT_STUFF;
rx_errors = true;
}
priv->can.can_stats.bus_error++;
if (rx_errors)
dev->stats.rx_errors++;
if (tx_errors)
dev->stats.tx_errors++;
can_rx_offload_queue_sorted(&priv->offload, skb, timestamp);
}
static void flexcan_irq_state(struct net_device *dev, u32 reg_esr)
{
struct flexcan_priv *priv = netdev_priv(dev);
struct flexcan_regs __iomem *regs = priv->regs;
struct sk_buff *skb;
struct can_frame *cf;
enum can_state new_state, rx_state, tx_state;
int flt;
struct can_berr_counter bec;
u32 timestamp;
timestamp = priv->read(&regs->timer) << 16;
flt = reg_esr & FLEXCAN_ESR_FLT_CONF_MASK;
if (likely(flt == FLEXCAN_ESR_FLT_CONF_ACTIVE)) {
tx_state = unlikely(reg_esr & FLEXCAN_ESR_TX_WRN) ?
CAN_STATE_ERROR_WARNING : CAN_STATE_ERROR_ACTIVE;
rx_state = unlikely(reg_esr & FLEXCAN_ESR_RX_WRN) ?
CAN_STATE_ERROR_WARNING : CAN_STATE_ERROR_ACTIVE;
new_state = max(tx_state, rx_state);
} else {
__flexcan_get_berr_counter(dev, &bec);
new_state = flt == FLEXCAN_ESR_FLT_CONF_PASSIVE ?
CAN_STATE_ERROR_PASSIVE : CAN_STATE_BUS_OFF;
rx_state = bec.rxerr >= bec.txerr ? new_state : 0;
tx_state = bec.rxerr <= bec.txerr ? new_state : 0;
}
/* state hasn't changed */
if (likely(new_state == priv->can.state))
return;
skb = alloc_can_err_skb(dev, &cf);
if (unlikely(!skb))
return;
can_change_state(dev, cf, tx_state, rx_state);
if (unlikely(new_state == CAN_STATE_BUS_OFF))
can_bus_off(dev);
can_rx_offload_queue_sorted(&priv->offload, skb, timestamp);
}
static inline struct flexcan_priv *rx_offload_to_priv(struct can_rx_offload *offload)
{
return container_of(offload, struct flexcan_priv, offload);
}
static unsigned int flexcan_mailbox_read(struct can_rx_offload *offload,
struct can_frame *cf,
u32 *timestamp, unsigned int n)
{
struct flexcan_priv *priv = rx_offload_to_priv(offload);
struct flexcan_regs __iomem *regs = priv->regs;
struct flexcan_mb __iomem *mb;
u32 reg_ctrl, reg_id, reg_iflag1;
int i;
mb = flexcan_get_mb(priv, n);
if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP) {
u32 code;
do {
reg_ctrl = priv->read(&mb->can_ctrl);
} while (reg_ctrl & FLEXCAN_MB_CODE_RX_BUSY_BIT);
/* is this MB empty? */
code = reg_ctrl & FLEXCAN_MB_CODE_MASK;
if ((code != FLEXCAN_MB_CODE_RX_FULL) &&
(code != FLEXCAN_MB_CODE_RX_OVERRUN))
return 0;
if (code == FLEXCAN_MB_CODE_RX_OVERRUN) {
/* This MB was overrun, we lost data */
offload->dev->stats.rx_over_errors++;
offload->dev->stats.rx_errors++;
}
} else {
reg_iflag1 = priv->read(&regs->iflag1);
if (!(reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE))
return 0;
reg_ctrl = priv->read(&mb->can_ctrl);
}
/* increase timstamp to full 32 bit */
*timestamp = reg_ctrl << 16;
reg_id = priv->read(&mb->can_id);
if (reg_ctrl & FLEXCAN_MB_CNT_IDE)
cf->can_id = ((reg_id >> 0) & CAN_EFF_MASK) | CAN_EFF_FLAG;
else
cf->can_id = (reg_id >> 18) & CAN_SFF_MASK;
if (reg_ctrl & FLEXCAN_MB_CNT_RTR)
cf->can_id |= CAN_RTR_FLAG;
cf->can_dlc = get_can_dlc((reg_ctrl >> 16) & 0xf);
for (i = 0; i < cf->can_dlc; i += sizeof(u32)) {
__be32 data = cpu_to_be32(priv->read(&mb->data[i / sizeof(u32)]));
*(__be32 *)(cf->data + i) = data;
}
/* mark as read */
if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP) {
/* Clear IRQ */
if (n < 32)
priv->write(BIT(n), &regs->iflag1);
else
priv->write(BIT(n - 32), &regs->iflag2);
} else {
priv->write(FLEXCAN_IFLAG_RX_FIFO_AVAILABLE, &regs->iflag1);
}
/* Read the Free Running Timer. It is optional but recommended
* to unlock Mailbox as soon as possible and make it available
* for reception.
*/
priv->read(&regs->timer);
return 1;
}
static inline u64 flexcan_read_reg_iflag_rx(struct flexcan_priv *priv)
{
struct flexcan_regs __iomem *regs = priv->regs;
u32 iflag1, iflag2;
iflag2 = priv->read(&regs->iflag2) & priv->reg_imask2_default &
~FLEXCAN_IFLAG_MB(priv->tx_mb_idx);
iflag1 = priv->read(&regs->iflag1) & priv->reg_imask1_default;
return (u64)iflag2 << 32 | iflag1;
}
static irqreturn_t flexcan_irq(int irq, void *dev_id)
{
struct net_device *dev = dev_id;
struct net_device_stats *stats = &dev->stats;
struct flexcan_priv *priv = netdev_priv(dev);
struct flexcan_regs __iomem *regs = priv->regs;
irqreturn_t handled = IRQ_NONE;
u32 reg_iflag2, reg_esr;
enum can_state last_state = priv->can.state;
/* reception interrupt */
if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP) {
u64 reg_iflag;
int ret;
while ((reg_iflag = flexcan_read_reg_iflag_rx(priv))) {
handled = IRQ_HANDLED;
ret = can_rx_offload_irq_offload_timestamp(&priv->offload,
reg_iflag);
if (!ret)
break;
}
} else {
u32 reg_iflag1;
reg_iflag1 = priv->read(&regs->iflag1);
if (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE) {
handled = IRQ_HANDLED;
can_rx_offload_irq_offload_fifo(&priv->offload);
}
/* FIFO overflow interrupt */
if (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_OVERFLOW) {
handled = IRQ_HANDLED;
priv->write(FLEXCAN_IFLAG_RX_FIFO_OVERFLOW,
&regs->iflag1);
dev->stats.rx_over_errors++;
dev->stats.rx_errors++;
}
}
reg_iflag2 = priv->read(&regs->iflag2);
/* transmission complete interrupt */
if (reg_iflag2 & FLEXCAN_IFLAG_MB(priv->tx_mb_idx)) {
u32 reg_ctrl = priv->read(&priv->tx_mb->can_ctrl);
handled = IRQ_HANDLED;
stats->tx_bytes += can_rx_offload_get_echo_skb(&priv->offload,
0, reg_ctrl << 16);
stats->tx_packets++;
can_led_event(dev, CAN_LED_EVENT_TX);
/* after sending a RTR frame MB is in RX mode */
priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
&priv->tx_mb->can_ctrl);
priv->write(FLEXCAN_IFLAG_MB(priv->tx_mb_idx), &regs->iflag2);
netif_wake_queue(dev);
}
reg_esr = priv->read(&regs->esr);
/* ACK all bus error and state change IRQ sources */
if (reg_esr & FLEXCAN_ESR_ALL_INT) {
handled = IRQ_HANDLED;
priv->write(reg_esr & FLEXCAN_ESR_ALL_INT, &regs->esr);
}
/* state change interrupt or broken error state quirk fix is enabled */
if ((reg_esr & FLEXCAN_ESR_ERR_STATE) ||
(priv->devtype_data->quirks & (FLEXCAN_QUIRK_BROKEN_WERR_STATE |
FLEXCAN_QUIRK_BROKEN_PERR_STATE)))
flexcan_irq_state(dev, reg_esr);
/* bus error IRQ - handle if bus error reporting is activated */
if ((reg_esr & FLEXCAN_ESR_ERR_BUS) &&
(priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
flexcan_irq_bus_err(dev, reg_esr);
/* availability of error interrupt among state transitions in case
* bus error reporting is de-activated and
* FLEXCAN_QUIRK_BROKEN_PERR_STATE is enabled:
* +--------------------------------------------------------------+
* | +----------------------------------------------+ [stopped / |
* | | | sleeping] -+
* +-+-> active <-> warning <-> passive -> bus off -+
* ___________^^^^^^^^^^^^_______________________________
* disabled(1) enabled disabled
*
* (1): enabled if FLEXCAN_QUIRK_BROKEN_WERR_STATE is enabled
*/
if ((last_state != priv->can.state) &&
(priv->devtype_data->quirks & FLEXCAN_QUIRK_BROKEN_PERR_STATE) &&
!(priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)) {
switch (priv->can.state) {
case CAN_STATE_ERROR_ACTIVE:
if (priv->devtype_data->quirks &
FLEXCAN_QUIRK_BROKEN_WERR_STATE)
flexcan_error_irq_enable(priv);
else
flexcan_error_irq_disable(priv);
break;
case CAN_STATE_ERROR_WARNING:
flexcan_error_irq_enable(priv);
break;
case CAN_STATE_ERROR_PASSIVE:
case CAN_STATE_BUS_OFF:
flexcan_error_irq_disable(priv);
break;
default:
break;
}
}
return handled;
}
static void flexcan_set_bittiming(struct net_device *dev)
{
const struct flexcan_priv *priv = netdev_priv(dev);
const struct can_bittiming *bt = &priv->can.bittiming;
struct flexcan_regs __iomem *regs = priv->regs;
u32 reg;
reg = priv->read(&regs->ctrl);
reg &= ~(FLEXCAN_CTRL_PRESDIV(0xff) |
FLEXCAN_CTRL_RJW(0x3) |
FLEXCAN_CTRL_PSEG1(0x7) |
FLEXCAN_CTRL_PSEG2(0x7) |
FLEXCAN_CTRL_PROPSEG(0x7) |
FLEXCAN_CTRL_LPB |
FLEXCAN_CTRL_SMP |
FLEXCAN_CTRL_LOM);
reg |= FLEXCAN_CTRL_PRESDIV(bt->brp - 1) |
FLEXCAN_CTRL_PSEG1(bt->phase_seg1 - 1) |
FLEXCAN_CTRL_PSEG2(bt->phase_seg2 - 1) |
FLEXCAN_CTRL_RJW(bt->sjw - 1) |
FLEXCAN_CTRL_PROPSEG(bt->prop_seg - 1);
if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
reg |= FLEXCAN_CTRL_LPB;
if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
reg |= FLEXCAN_CTRL_LOM;
if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
reg |= FLEXCAN_CTRL_SMP;
netdev_dbg(dev, "writing ctrl=0x%08x\n", reg);
priv->write(reg, &regs->ctrl);
/* print chip status */
netdev_dbg(dev, "%s: mcr=0x%08x ctrl=0x%08x\n", __func__,
priv->read(&regs->mcr), priv->read(&regs->ctrl));
}
/* flexcan_chip_start
*
* this functions is entered with clocks enabled
*
*/
static int flexcan_chip_start(struct net_device *dev)
{
struct flexcan_priv *priv = netdev_priv(dev);
struct flexcan_regs __iomem *regs = priv->regs;
u32 reg_mcr, reg_ctrl, reg_ctrl2, reg_mecr;
int err, i;
struct flexcan_mb __iomem *mb;
/* enable module */
err = flexcan_chip_enable(priv);
if (err)
return err;
/* soft reset */
err = flexcan_chip_softreset(priv);
if (err)
goto out_chip_disable;
flexcan_set_bittiming(dev);
/* MCR
*
* enable freeze
* halt now
* only supervisor access
* enable warning int
* enable individual RX masking
* choose format C
* set max mailbox number
*/
reg_mcr = priv->read(&regs->mcr);
reg_mcr &= ~FLEXCAN_MCR_MAXMB(0xff);
reg_mcr |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_HALT | FLEXCAN_MCR_SUPV |
FLEXCAN_MCR_WRN_EN | FLEXCAN_MCR_IRMQ | FLEXCAN_MCR_IDAM_C |
FLEXCAN_MCR_MAXMB(priv->tx_mb_idx);
/* MCR
*
* FIFO:
* - disable for timestamp mode
* - enable for FIFO mode
*/
if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP)
reg_mcr &= ~FLEXCAN_MCR_FEN;
else
reg_mcr |= FLEXCAN_MCR_FEN;
/* MCR
*
* NOTE: In loopback mode, the CAN_MCR[SRXDIS] cannot be
* asserted because this will impede the self reception
* of a transmitted message. This is not documented in
* earlier versions of flexcan block guide.
*
* Self Reception:
* - enable Self Reception for loopback mode
* (by clearing "Self Reception Disable" bit)
* - disable for normal operation
*/
if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
reg_mcr &= ~FLEXCAN_MCR_SRX_DIS;
else
reg_mcr |= FLEXCAN_MCR_SRX_DIS;
netdev_dbg(dev, "%s: writing mcr=0x%08x", __func__, reg_mcr);
priv->write(reg_mcr, &regs->mcr);
/* CTRL
*
* disable timer sync feature
*
* disable auto busoff recovery
* transmit lowest buffer first
*
* enable tx and rx warning interrupt
* enable bus off interrupt
* (== FLEXCAN_CTRL_ERR_STATE)
*/
reg_ctrl = priv->read(&regs->ctrl);
reg_ctrl &= ~FLEXCAN_CTRL_TSYN;
reg_ctrl |= FLEXCAN_CTRL_BOFF_REC | FLEXCAN_CTRL_LBUF |
FLEXCAN_CTRL_ERR_STATE;
/* enable the "error interrupt" (FLEXCAN_CTRL_ERR_MSK),
* on most Flexcan cores, too. Otherwise we don't get
* any error warning or passive interrupts.
*/
if (priv->devtype_data->quirks & FLEXCAN_QUIRK_BROKEN_WERR_STATE ||
priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
reg_ctrl |= FLEXCAN_CTRL_ERR_MSK;
else
reg_ctrl &= ~FLEXCAN_CTRL_ERR_MSK;
/* save for later use */
priv->reg_ctrl_default = reg_ctrl;
/* leave interrupts disabled for now */
reg_ctrl &= ~FLEXCAN_CTRL_ERR_ALL;
netdev_dbg(dev, "%s: writing ctrl=0x%08x", __func__, reg_ctrl);
priv->write(reg_ctrl, &regs->ctrl);
if ((priv->devtype_data->quirks & FLEXCAN_QUIRK_ENABLE_EACEN_RRS)) {
reg_ctrl2 = priv->read(&regs->ctrl2);
reg_ctrl2 |= FLEXCAN_CTRL2_EACEN | FLEXCAN_CTRL2_RRS;
priv->write(reg_ctrl2, &regs->ctrl2);
}
if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP) {
for (i = priv->offload.mb_first; i <= priv->offload.mb_last; i++) {
mb = flexcan_get_mb(priv, i);
priv->write(FLEXCAN_MB_CODE_RX_EMPTY,
&mb->can_ctrl);
}
} else {
/* clear and invalidate unused mailboxes first */
for (i = FLEXCAN_TX_MB_RESERVED_OFF_FIFO; i < priv->mb_count; i++) {
mb = flexcan_get_mb(priv, i);
priv->write(FLEXCAN_MB_CODE_RX_INACTIVE,
&mb->can_ctrl);
}
}
/* Errata ERR005829: mark first TX mailbox as INACTIVE */
priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
&priv->tx_mb_reserved->can_ctrl);
/* mark TX mailbox as INACTIVE */
priv->write(FLEXCAN_MB_CODE_TX_INACTIVE,
&priv->tx_mb->can_ctrl);
/* acceptance mask/acceptance code (accept everything) */
priv->write(0x0, &regs->rxgmask);
priv->write(0x0, &regs->rx14mask);
priv->write(0x0, &regs->rx15mask);
if (priv->devtype_data->quirks & FLEXCAN_QUIRK_DISABLE_RXFG)
priv->write(0x0, &regs->rxfgmask);
/* clear acceptance filters */
for (i = 0; i < priv->mb_count; i++)
priv->write(0, &regs->rximr[i]);
/* On Vybrid, disable memory error detection interrupts
* and freeze mode.
* This also works around errata e5295 which generates
* false positive memory errors and put the device in
* freeze mode.
*/
if (priv->devtype_data->quirks & FLEXCAN_QUIRK_DISABLE_MECR) {
/* Follow the protocol as described in "Detection
* and Correction of Memory Errors" to write to
* MECR register
*/
reg_ctrl2 = priv->read(&regs->ctrl2);
reg_ctrl2 |= FLEXCAN_CTRL2_ECRWRE;
priv->write(reg_ctrl2, &regs->ctrl2);
reg_mecr = priv->read(&regs->mecr);
reg_mecr &= ~FLEXCAN_MECR_ECRWRDIS;
priv->write(reg_mecr, &regs->mecr);
reg_mecr &= ~(FLEXCAN_MECR_NCEFAFRZ | FLEXCAN_MECR_HANCEI_MSK |
FLEXCAN_MECR_FANCEI_MSK);
priv->write(reg_mecr, &regs->mecr);
}
err = flexcan_transceiver_enable(priv);
if (err)
goto out_chip_disable;
/* synchronize with the can bus */
err = flexcan_chip_unfreeze(priv);
if (err)
goto out_transceiver_disable;
priv->can.state = CAN_STATE_ERROR_ACTIVE;
/* enable interrupts atomically */
disable_irq(dev->irq);
priv->write(priv->reg_ctrl_default, &regs->ctrl);
priv->write(priv->reg_imask1_default, &regs->imask1);
priv->write(priv->reg_imask2_default, &regs->imask2);
enable_irq(dev->irq);
/* print chip status */
netdev_dbg(dev, "%s: reading mcr=0x%08x ctrl=0x%08x\n", __func__,
priv->read(&regs->mcr), priv->read(&regs->ctrl));
return 0;
out_transceiver_disable:
flexcan_transceiver_disable(priv);
out_chip_disable:
flexcan_chip_disable(priv);
return err;
}
/* flexcan_chip_stop
*
* this functions is entered with clocks enabled
*/
static void flexcan_chip_stop(struct net_device *dev)
{
struct flexcan_priv *priv = netdev_priv(dev);
struct flexcan_regs __iomem *regs = priv->regs;
/* freeze + disable module */
flexcan_chip_freeze(priv);
flexcan_chip_disable(priv);
/* Disable all interrupts */
priv->write(0, &regs->imask2);
priv->write(0, &regs->imask1);
priv->write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL,
&regs->ctrl);
flexcan_transceiver_disable(priv);
priv->can.state = CAN_STATE_STOPPED;
}
static int flexcan_open(struct net_device *dev)
{
struct flexcan_priv *priv = netdev_priv(dev);
int err;
err = clk_prepare_enable(priv->clk_ipg);
if (err)
return err;
err = clk_prepare_enable(priv->clk_per);
if (err)
goto out_disable_ipg;
err = open_candev(dev);
if (err)
goto out_disable_per;
err = request_irq(dev->irq, flexcan_irq, IRQF_SHARED, dev->name, dev);
if (err)
goto out_close;
priv->mb_size = sizeof(struct flexcan_mb) + CAN_MAX_DLEN;
priv->mb_count = (sizeof(priv->regs->mb[0]) / priv->mb_size) +
(sizeof(priv->regs->mb[1]) / priv->mb_size);
if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP)
priv->tx_mb_reserved =
flexcan_get_mb(priv, FLEXCAN_TX_MB_RESERVED_OFF_TIMESTAMP);
else
priv->tx_mb_reserved =
flexcan_get_mb(priv, FLEXCAN_TX_MB_RESERVED_OFF_FIFO);
priv->tx_mb_idx = priv->mb_count - 1;
priv->tx_mb = flexcan_get_mb(priv, priv->tx_mb_idx);
priv->reg_imask1_default = 0;
priv->reg_imask2_default = FLEXCAN_IFLAG_MB(priv->tx_mb_idx);
priv->offload.mailbox_read = flexcan_mailbox_read;
if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP) {
u64 imask;
priv->offload.mb_first = FLEXCAN_RX_MB_OFF_TIMESTAMP_FIRST;
priv->offload.mb_last = priv->mb_count - 2;
imask = GENMASK_ULL(priv->offload.mb_last,
priv->offload.mb_first);
priv->reg_imask1_default |= imask;
priv->reg_imask2_default |= imask >> 32;
err = can_rx_offload_add_timestamp(dev, &priv->offload);
} else {
priv->reg_imask1_default |= FLEXCAN_IFLAG_RX_FIFO_OVERFLOW |
FLEXCAN_IFLAG_RX_FIFO_AVAILABLE;
err = can_rx_offload_add_fifo(dev, &priv->offload,
FLEXCAN_NAPI_WEIGHT);
}
if (err)
goto out_free_irq;
/* start chip and queuing */
err = flexcan_chip_start(dev);
if (err)
goto out_offload_del;
can_led_event(dev, CAN_LED_EVENT_OPEN);
can_rx_offload_enable(&priv->offload);
netif_start_queue(dev);
return 0;
out_offload_del:
can_rx_offload_del(&priv->offload);
out_free_irq:
free_irq(dev->irq, dev);
out_close:
close_candev(dev);
out_disable_per:
clk_disable_unprepare(priv->clk_per);
out_disable_ipg:
clk_disable_unprepare(priv->clk_ipg);
return err;
}
static int flexcan_close(struct net_device *dev)
{
struct flexcan_priv *priv = netdev_priv(dev);
netif_stop_queue(dev);
can_rx_offload_disable(&priv->offload);
flexcan_chip_stop(dev);
can_rx_offload_del(&priv->offload);
free_irq(dev->irq, dev);
clk_disable_unprepare(priv->clk_per);
clk_disable_unprepare(priv->clk_ipg);
close_candev(dev);
can_led_event(dev, CAN_LED_EVENT_STOP);
return 0;
}
static int flexcan_set_mode(struct net_device *dev, enum can_mode mode)
{
int err;
switch (mode) {
case CAN_MODE_START:
err = flexcan_chip_start(dev);
if (err)
return err;
netif_wake_queue(dev);
break;
default:
return -EOPNOTSUPP;
}
return 0;
}
static const struct net_device_ops flexcan_netdev_ops = {
.ndo_open = flexcan_open,
.ndo_stop = flexcan_close,
.ndo_start_xmit = flexcan_start_xmit,
.ndo_change_mtu = can_change_mtu,
};
static int register_flexcandev(struct net_device *dev)
{
struct flexcan_priv *priv = netdev_priv(dev);
struct flexcan_regs __iomem *regs = priv->regs;
u32 reg, err;
err = clk_prepare_enable(priv->clk_ipg);
if (err)
return err;
err = clk_prepare_enable(priv->clk_per);
if (err)
goto out_disable_ipg;
/* select "bus clock", chip must be disabled */
err = flexcan_chip_disable(priv);
if (err)
goto out_disable_per;
reg = priv->read(&regs->ctrl);
reg |= FLEXCAN_CTRL_CLK_SRC;
priv->write(reg, &regs->ctrl);
err = flexcan_chip_enable(priv);
if (err)
goto out_chip_disable;
/* set freeze, halt and activate FIFO, restrict register access */
reg = priv->read(&regs->mcr);
reg |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_HALT |
FLEXCAN_MCR_FEN | FLEXCAN_MCR_SUPV;
priv->write(reg, &regs->mcr);
/* Currently we only support newer versions of this core
* featuring a RX hardware FIFO (although this driver doesn't
* make use of it on some cores). Older cores, found on some
* Coldfire derivates are not tested.
*/
reg = priv->read(&regs->mcr);
if (!(reg & FLEXCAN_MCR_FEN)) {
netdev_err(dev, "Could not enable RX FIFO, unsupported core\n");
err = -ENODEV;
goto out_chip_disable;
}
err = register_candev(dev);
/* disable core and turn off clocks */
out_chip_disable:
flexcan_chip_disable(priv);
out_disable_per:
clk_disable_unprepare(priv->clk_per);
out_disable_ipg:
clk_disable_unprepare(priv->clk_ipg);
return err;
}
static void unregister_flexcandev(struct net_device *dev)
{
unregister_candev(dev);
}
static int flexcan_setup_stop_mode(struct platform_device *pdev)
{
struct net_device *dev = platform_get_drvdata(pdev);
struct device_node *np = pdev->dev.of_node;
struct device_node *gpr_np;
struct flexcan_priv *priv;
phandle phandle;
u32 out_val[5];
int ret;
if (!np)
return -EINVAL;
/* stop mode property format is:
* <&gpr req_gpr req_bit ack_gpr ack_bit>.
*/
ret = of_property_read_u32_array(np, "fsl,stop-mode", out_val,
ARRAY_SIZE(out_val));
if (ret) {
dev_dbg(&pdev->dev, "no stop-mode property\n");
return ret;
}
phandle = *out_val;
gpr_np = of_find_node_by_phandle(phandle);
if (!gpr_np) {
dev_dbg(&pdev->dev, "could not find gpr node by phandle\n");
return -ENODEV;
}
priv = netdev_priv(dev);
priv->stm.gpr = syscon_node_to_regmap(gpr_np);
of_node_put(gpr_np);
if (IS_ERR(priv->stm.gpr)) {
dev_dbg(&pdev->dev, "could not find gpr regmap\n");
return PTR_ERR(priv->stm.gpr);
}
priv->stm.req_gpr = out_val[1];
priv->stm.req_bit = out_val[2];
priv->stm.ack_gpr = out_val[3];
priv->stm.ack_bit = out_val[4];
dev_dbg(&pdev->dev,
"gpr %s req_gpr=0x02%x req_bit=%u ack_gpr=0x02%x ack_bit=%u\n",
gpr_np->full_name, priv->stm.req_gpr, priv->stm.req_bit,
priv->stm.ack_gpr, priv->stm.ack_bit);
device_set_wakeup_capable(&pdev->dev, true);
return 0;
}
static const struct of_device_id flexcan_of_match[] = {
{ .compatible = "fsl,imx6q-flexcan", .data = &fsl_imx6q_devtype_data, },
{ .compatible = "fsl,imx28-flexcan", .data = &fsl_imx28_devtype_data, },
{ .compatible = "fsl,imx53-flexcan", .data = &fsl_imx25_devtype_data, },
{ .compatible = "fsl,imx35-flexcan", .data = &fsl_imx25_devtype_data, },
{ .compatible = "fsl,imx25-flexcan", .data = &fsl_imx25_devtype_data, },
{ .compatible = "fsl,p1010-flexcan", .data = &fsl_p1010_devtype_data, },
{ .compatible = "fsl,vf610-flexcan", .data = &fsl_vf610_devtype_data, },
{ .compatible = "fsl,ls1021ar2-flexcan", .data = &fsl_ls1021a_r2_devtype_data, },
{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, flexcan_of_match);
static const struct platform_device_id flexcan_id_table[] = {
{ .name = "flexcan", .driver_data = (kernel_ulong_t)&fsl_p1010_devtype_data, },
{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(platform, flexcan_id_table);
static int flexcan_probe(struct platform_device *pdev)
{
const struct of_device_id *of_id;
const struct flexcan_devtype_data *devtype_data;
struct net_device *dev;
struct flexcan_priv *priv;
struct regulator *reg_xceiver;
struct resource *mem;
struct clk *clk_ipg = NULL, *clk_per = NULL;
struct flexcan_regs __iomem *regs;
int err, irq;
u32 clock_freq = 0;
reg_xceiver = devm_regulator_get(&pdev->dev, "xceiver");
if (PTR_ERR(reg_xceiver) == -EPROBE_DEFER)
return -EPROBE_DEFER;
else if (IS_ERR(reg_xceiver))
reg_xceiver = NULL;
if (pdev->dev.of_node)
of_property_read_u32(pdev->dev.of_node,
"clock-frequency", &clock_freq);
if (!clock_freq) {
clk_ipg = devm_clk_get(&pdev->dev, "ipg");
if (IS_ERR(clk_ipg)) {
dev_err(&pdev->dev, "no ipg clock defined\n");
return PTR_ERR(clk_ipg);
}
clk_per = devm_clk_get(&pdev->dev, "per");
if (IS_ERR(clk_per)) {
dev_err(&pdev->dev, "no per clock defined\n");
return PTR_ERR(clk_per);
}
clock_freq = clk_get_rate(clk_per);
}
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
irq = platform_get_irq(pdev, 0);
if (irq <= 0)
return -ENODEV;
regs = devm_ioremap_resource(&pdev->dev, mem);
if (IS_ERR(regs))
return PTR_ERR(regs);
of_id = of_match_device(flexcan_of_match, &pdev->dev);
if (of_id) {
devtype_data = of_id->data;
} else if (platform_get_device_id(pdev)->driver_data) {
devtype_data = (struct flexcan_devtype_data *)
platform_get_device_id(pdev)->driver_data;
} else {
return -ENODEV;
}
dev = alloc_candev(sizeof(struct flexcan_priv), 1);
if (!dev)
return -ENOMEM;
platform_set_drvdata(pdev, dev);
SET_NETDEV_DEV(dev, &pdev->dev);
dev->netdev_ops = &flexcan_netdev_ops;
dev->irq = irq;
dev->flags |= IFF_ECHO;
priv = netdev_priv(dev);
if (of_property_read_bool(pdev->dev.of_node, "big-endian") ||
devtype_data->quirks & FLEXCAN_QUIRK_DEFAULT_BIG_ENDIAN) {
priv->read = flexcan_read_be;
priv->write = flexcan_write_be;
} else {
priv->read = flexcan_read_le;
priv->write = flexcan_write_le;
}
priv->can.clock.freq = clock_freq;
priv->can.bittiming_const = &flexcan_bittiming_const;
priv->can.do_set_mode = flexcan_set_mode;
priv->can.do_get_berr_counter = flexcan_get_berr_counter;
priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
CAN_CTRLMODE_LISTENONLY | CAN_CTRLMODE_3_SAMPLES |
CAN_CTRLMODE_BERR_REPORTING;
priv->regs = regs;
priv->clk_ipg = clk_ipg;
priv->clk_per = clk_per;
priv->devtype_data = devtype_data;
priv->reg_xceiver = reg_xceiver;
err = register_flexcandev(dev);
if (err) {
dev_err(&pdev->dev, "registering netdev failed\n");
goto failed_register;
}
devm_can_led_init(dev);
if (priv->devtype_data->quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE) {
err = flexcan_setup_stop_mode(pdev);
if (err)
dev_dbg(&pdev->dev, "failed to setup stop-mode\n");
}
return 0;
failed_register:
free_candev(dev);
return err;
}
static int flexcan_remove(struct platform_device *pdev)
{
struct net_device *dev = platform_get_drvdata(pdev);
unregister_flexcandev(dev);
free_candev(dev);
return 0;
}
static int __maybe_unused flexcan_suspend(struct device *device)
{
struct net_device *dev = dev_get_drvdata(device);
struct flexcan_priv *priv = netdev_priv(dev);
int err;
if (netif_running(dev)) {
/* if wakeup is enabled, enter stop mode
* else enter disabled mode.
*/
if (device_may_wakeup(device)) {
enable_irq_wake(dev->irq);
flexcan_enter_stop_mode(priv);
} else {
err = flexcan_chip_disable(priv);
if (err)
return err;
}
netif_stop_queue(dev);
netif_device_detach(dev);
}
priv->can.state = CAN_STATE_SLEEPING;
return 0;
}
static int __maybe_unused flexcan_resume(struct device *device)
{
struct net_device *dev = dev_get_drvdata(device);
struct flexcan_priv *priv = netdev_priv(dev);
int err;
priv->can.state = CAN_STATE_ERROR_ACTIVE;
if (netif_running(dev)) {
netif_device_attach(dev);
netif_start_queue(dev);
if (device_may_wakeup(device)) {
disable_irq_wake(dev->irq);
} else {
err = flexcan_chip_enable(priv);
if (err)
return err;
}
}
return 0;
}
static int __maybe_unused flexcan_noirq_suspend(struct device *device)
{
struct net_device *dev = dev_get_drvdata(device);
struct flexcan_priv *priv = netdev_priv(dev);
if (netif_running(dev) && device_may_wakeup(device))
flexcan_enable_wakeup_irq(priv, true);
return 0;
}
static int __maybe_unused flexcan_noirq_resume(struct device *device)
{
struct net_device *dev = dev_get_drvdata(device);
struct flexcan_priv *priv = netdev_priv(dev);
if (netif_running(dev) && device_may_wakeup(device)) {
flexcan_enable_wakeup_irq(priv, false);
flexcan_exit_stop_mode(priv);
}
return 0;
}
static const struct dev_pm_ops flexcan_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(flexcan_suspend, flexcan_resume)
SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(flexcan_noirq_suspend, flexcan_noirq_resume)
};
static struct platform_driver flexcan_driver = {
.driver = {
.name = DRV_NAME,
.pm = &flexcan_pm_ops,
.of_match_table = flexcan_of_match,
},
.probe = flexcan_probe,
.remove = flexcan_remove,
.id_table = flexcan_id_table,
};
module_platform_driver(flexcan_driver);
MODULE_AUTHOR("Sascha Hauer <kernel@pengutronix.de>, "
"Marc Kleine-Budde <kernel@pengutronix.de>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("CAN port driver for flexcan based chip");
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