// SPDX-License-Identifier: GPL-2.0 // CAN bus driver for Bosch M_CAN controller // Copyright (C) 2014 Freescale Semiconductor, Inc. // Dong Aisheng // Copyright (C) 2018-19 Texas Instruments Incorporated - http://www.ti.com/ /* Bosch M_CAN user manual can be obtained from: * https://github.com/linux-can/can-doc/tree/master/m_can */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "m_can.h" /* registers definition */ enum m_can_reg { M_CAN_CREL = 0x0, M_CAN_ENDN = 0x4, M_CAN_CUST = 0x8, M_CAN_DBTP = 0xc, M_CAN_TEST = 0x10, M_CAN_RWD = 0x14, M_CAN_CCCR = 0x18, M_CAN_NBTP = 0x1c, M_CAN_TSCC = 0x20, M_CAN_TSCV = 0x24, M_CAN_TOCC = 0x28, M_CAN_TOCV = 0x2c, M_CAN_ECR = 0x40, M_CAN_PSR = 0x44, /* TDCR Register only available for version >=3.1.x */ M_CAN_TDCR = 0x48, M_CAN_IR = 0x50, M_CAN_IE = 0x54, M_CAN_ILS = 0x58, M_CAN_ILE = 0x5c, M_CAN_GFC = 0x80, M_CAN_SIDFC = 0x84, M_CAN_XIDFC = 0x88, M_CAN_XIDAM = 0x90, M_CAN_HPMS = 0x94, M_CAN_NDAT1 = 0x98, M_CAN_NDAT2 = 0x9c, M_CAN_RXF0C = 0xa0, M_CAN_RXF0S = 0xa4, M_CAN_RXF0A = 0xa8, M_CAN_RXBC = 0xac, M_CAN_RXF1C = 0xb0, M_CAN_RXF1S = 0xb4, M_CAN_RXF1A = 0xb8, M_CAN_RXESC = 0xbc, M_CAN_TXBC = 0xc0, M_CAN_TXFQS = 0xc4, M_CAN_TXESC = 0xc8, M_CAN_TXBRP = 0xcc, M_CAN_TXBAR = 0xd0, M_CAN_TXBCR = 0xd4, M_CAN_TXBTO = 0xd8, M_CAN_TXBCF = 0xdc, M_CAN_TXBTIE = 0xe0, M_CAN_TXBCIE = 0xe4, M_CAN_TXEFC = 0xf0, M_CAN_TXEFS = 0xf4, M_CAN_TXEFA = 0xf8, }; /* napi related */ #define M_CAN_NAPI_WEIGHT 64 /* message ram configuration data length */ #define MRAM_CFG_LEN 8 /* Core Release Register (CREL) */ #define CREL_REL_MASK GENMASK(31, 28) #define CREL_STEP_MASK GENMASK(27, 24) #define CREL_SUBSTEP_MASK GENMASK(23, 20) /* Data Bit Timing & Prescaler Register (DBTP) */ #define DBTP_TDC BIT(23) #define DBTP_DBRP_MASK GENMASK(20, 16) #define DBTP_DTSEG1_MASK GENMASK(12, 8) #define DBTP_DTSEG2_MASK GENMASK(7, 4) #define DBTP_DSJW_MASK GENMASK(3, 0) /* Transmitter Delay Compensation Register (TDCR) */ #define TDCR_TDCO_MASK GENMASK(14, 8) #define TDCR_TDCF_MASK GENMASK(6, 0) /* Test Register (TEST) */ #define TEST_LBCK BIT(4) /* CC Control Register (CCCR) */ #define CCCR_TXP BIT(14) #define CCCR_TEST BIT(7) #define CCCR_DAR BIT(6) #define CCCR_MON BIT(5) #define CCCR_CSR BIT(4) #define CCCR_CSA BIT(3) #define CCCR_ASM BIT(2) #define CCCR_CCE BIT(1) #define CCCR_INIT BIT(0) /* for version 3.0.x */ #define CCCR_CMR_MASK GENMASK(11, 10) #define CCCR_CMR_CANFD 0x1 #define CCCR_CMR_CANFD_BRS 0x2 #define CCCR_CMR_CAN 0x3 #define CCCR_CME_MASK GENMASK(9, 8) #define CCCR_CME_CAN 0 #define CCCR_CME_CANFD 0x1 #define CCCR_CME_CANFD_BRS 0x2 /* for version >=3.1.x */ #define CCCR_EFBI BIT(13) #define CCCR_PXHD BIT(12) #define CCCR_BRSE BIT(9) #define CCCR_FDOE BIT(8) /* for version >=3.2.x */ #define CCCR_NISO BIT(15) /* for version >=3.3.x */ #define CCCR_WMM BIT(11) #define CCCR_UTSU BIT(10) /* Nominal Bit Timing & Prescaler Register (NBTP) */ #define NBTP_NSJW_MASK GENMASK(31, 25) #define NBTP_NBRP_MASK GENMASK(24, 16) #define NBTP_NTSEG1_MASK GENMASK(15, 8) #define NBTP_NTSEG2_MASK GENMASK(6, 0) /* Timestamp Counter Configuration Register (TSCC) */ #define TSCC_TCP_MASK GENMASK(19, 16) #define TSCC_TSS_MASK GENMASK(1, 0) #define TSCC_TSS_DISABLE 0x0 #define TSCC_TSS_INTERNAL 0x1 #define TSCC_TSS_EXTERNAL 0x2 /* Timestamp Counter Value Register (TSCV) */ #define TSCV_TSC_MASK GENMASK(15, 0) /* Error Counter Register (ECR) */ #define ECR_RP BIT(15) #define ECR_REC_MASK GENMASK(14, 8) #define ECR_TEC_MASK GENMASK(7, 0) /* Protocol Status Register (PSR) */ #define PSR_BO BIT(7) #define PSR_EW BIT(6) #define PSR_EP BIT(5) #define PSR_LEC_MASK GENMASK(2, 0) /* Interrupt Register (IR) */ #define IR_ALL_INT 0xffffffff /* Renamed bits for versions > 3.1.x */ #define IR_ARA BIT(29) #define IR_PED BIT(28) #define IR_PEA BIT(27) /* Bits for version 3.0.x */ #define IR_STE BIT(31) #define IR_FOE BIT(30) #define IR_ACKE BIT(29) #define IR_BE BIT(28) #define IR_CRCE BIT(27) #define IR_WDI BIT(26) #define IR_BO BIT(25) #define IR_EW BIT(24) #define IR_EP BIT(23) #define IR_ELO BIT(22) #define IR_BEU BIT(21) #define IR_BEC BIT(20) #define IR_DRX BIT(19) #define IR_TOO BIT(18) #define IR_MRAF BIT(17) #define IR_TSW BIT(16) #define IR_TEFL BIT(15) #define IR_TEFF BIT(14) #define IR_TEFW BIT(13) #define IR_TEFN BIT(12) #define IR_TFE BIT(11) #define IR_TCF BIT(10) #define IR_TC BIT(9) #define IR_HPM BIT(8) #define IR_RF1L BIT(7) #define IR_RF1F BIT(6) #define IR_RF1W BIT(5) #define IR_RF1N BIT(4) #define IR_RF0L BIT(3) #define IR_RF0F BIT(2) #define IR_RF0W BIT(1) #define IR_RF0N BIT(0) #define IR_ERR_STATE (IR_BO | IR_EW | IR_EP) /* Interrupts for version 3.0.x */ #define IR_ERR_LEC_30X (IR_STE | IR_FOE | IR_ACKE | IR_BE | IR_CRCE) #define IR_ERR_BUS_30X (IR_ERR_LEC_30X | IR_WDI | IR_BEU | IR_BEC | \ IR_TOO | IR_MRAF | IR_TSW | IR_TEFL | IR_RF1L | \ IR_RF0L) #define IR_ERR_ALL_30X (IR_ERR_STATE | IR_ERR_BUS_30X) /* Interrupts for version >= 3.1.x */ #define IR_ERR_LEC_31X (IR_PED | IR_PEA) #define IR_ERR_BUS_31X (IR_ERR_LEC_31X | IR_WDI | IR_BEU | IR_BEC | \ IR_TOO | IR_MRAF | IR_TSW | IR_TEFL | IR_RF1L | \ IR_RF0L) #define IR_ERR_ALL_31X (IR_ERR_STATE | IR_ERR_BUS_31X) /* Interrupt Line Select (ILS) */ #define ILS_ALL_INT0 0x0 #define ILS_ALL_INT1 0xFFFFFFFF /* Interrupt Line Enable (ILE) */ #define ILE_EINT1 BIT(1) #define ILE_EINT0 BIT(0) /* Rx FIFO 0/1 Configuration (RXF0C/RXF1C) */ #define RXFC_FWM_MASK GENMASK(30, 24) #define RXFC_FS_MASK GENMASK(22, 16) /* Rx FIFO 0/1 Status (RXF0S/RXF1S) */ #define RXFS_RFL BIT(25) #define RXFS_FF BIT(24) #define RXFS_FPI_MASK GENMASK(21, 16) #define RXFS_FGI_MASK GENMASK(13, 8) #define RXFS_FFL_MASK GENMASK(6, 0) /* Rx Buffer / FIFO Element Size Configuration (RXESC) */ #define RXESC_RBDS_MASK GENMASK(10, 8) #define RXESC_F1DS_MASK GENMASK(6, 4) #define RXESC_F0DS_MASK GENMASK(2, 0) #define RXESC_64B 0x7 /* Tx Buffer Configuration (TXBC) */ #define TXBC_TFQS_MASK GENMASK(29, 24) #define TXBC_NDTB_MASK GENMASK(21, 16) /* Tx FIFO/Queue Status (TXFQS) */ #define TXFQS_TFQF BIT(21) #define TXFQS_TFQPI_MASK GENMASK(20, 16) #define TXFQS_TFGI_MASK GENMASK(12, 8) #define TXFQS_TFFL_MASK GENMASK(5, 0) /* Tx Buffer Element Size Configuration (TXESC) */ #define TXESC_TBDS_MASK GENMASK(2, 0) #define TXESC_TBDS_64B 0x7 /* Tx Event FIFO Configuration (TXEFC) */ #define TXEFC_EFS_MASK GENMASK(21, 16) /* Tx Event FIFO Status (TXEFS) */ #define TXEFS_TEFL BIT(25) #define TXEFS_EFF BIT(24) #define TXEFS_EFGI_MASK GENMASK(12, 8) #define TXEFS_EFFL_MASK GENMASK(5, 0) /* Tx Event FIFO Acknowledge (TXEFA) */ #define TXEFA_EFAI_MASK GENMASK(4, 0) /* Message RAM Configuration (in bytes) */ #define SIDF_ELEMENT_SIZE 4 #define XIDF_ELEMENT_SIZE 8 #define RXF0_ELEMENT_SIZE 72 #define RXF1_ELEMENT_SIZE 72 #define RXB_ELEMENT_SIZE 72 #define TXE_ELEMENT_SIZE 8 #define TXB_ELEMENT_SIZE 72 /* Message RAM Elements */ #define M_CAN_FIFO_ID 0x0 #define M_CAN_FIFO_DLC 0x4 #define M_CAN_FIFO_DATA 0x8 /* Rx Buffer Element */ /* R0 */ #define RX_BUF_ESI BIT(31) #define RX_BUF_XTD BIT(30) #define RX_BUF_RTR BIT(29) /* R1 */ #define RX_BUF_ANMF BIT(31) #define RX_BUF_FDF BIT(21) #define RX_BUF_BRS BIT(20) #define RX_BUF_RXTS_MASK GENMASK(15, 0) /* Tx Buffer Element */ /* T0 */ #define TX_BUF_ESI BIT(31) #define TX_BUF_XTD BIT(30) #define TX_BUF_RTR BIT(29) /* T1 */ #define TX_BUF_EFC BIT(23) #define TX_BUF_FDF BIT(21) #define TX_BUF_BRS BIT(20) #define TX_BUF_MM_MASK GENMASK(31, 24) #define TX_BUF_DLC_MASK GENMASK(19, 16) /* Tx event FIFO Element */ /* E1 */ #define TX_EVENT_MM_MASK GENMASK(31, 24) #define TX_EVENT_TXTS_MASK GENMASK(15, 0) /* The ID and DLC registers are adjacent in M_CAN FIFO memory, * and we can save a (potentially slow) bus round trip by combining * reads and writes to them. */ struct id_and_dlc { u32 id; u32 dlc; }; static inline u32 m_can_read(struct m_can_classdev *cdev, enum m_can_reg reg) { return cdev->ops->read_reg(cdev, reg); } static inline void m_can_write(struct m_can_classdev *cdev, enum m_can_reg reg, u32 val) { cdev->ops->write_reg(cdev, reg, val); } static int m_can_fifo_read(struct m_can_classdev *cdev, u32 fgi, unsigned int offset, void *val, size_t val_count) { u32 addr_offset = cdev->mcfg[MRAM_RXF0].off + fgi * RXF0_ELEMENT_SIZE + offset; return cdev->ops->read_fifo(cdev, addr_offset, val, val_count); } static int m_can_fifo_write(struct m_can_classdev *cdev, u32 fpi, unsigned int offset, const void *val, size_t val_count) { u32 addr_offset = cdev->mcfg[MRAM_TXB].off + fpi * TXB_ELEMENT_SIZE + offset; return cdev->ops->write_fifo(cdev, addr_offset, val, val_count); } static inline int m_can_fifo_write_no_off(struct m_can_classdev *cdev, u32 fpi, u32 val) { return cdev->ops->write_fifo(cdev, fpi, &val, 1); } static int m_can_txe_fifo_read(struct m_can_classdev *cdev, u32 fgi, u32 offset, u32 *val) { u32 addr_offset = cdev->mcfg[MRAM_TXE].off + fgi * TXE_ELEMENT_SIZE + offset; return cdev->ops->read_fifo(cdev, addr_offset, val, 1); } static inline bool m_can_tx_fifo_full(struct m_can_classdev *cdev) { return !!(m_can_read(cdev, M_CAN_TXFQS) & TXFQS_TFQF); } static void m_can_config_endisable(struct m_can_classdev *cdev, bool enable) { u32 cccr = m_can_read(cdev, M_CAN_CCCR); u32 timeout = 10; u32 val = 0; /* Clear the Clock stop request if it was set */ if (cccr & CCCR_CSR) cccr &= ~CCCR_CSR; if (enable) { /* enable m_can configuration */ m_can_write(cdev, M_CAN_CCCR, cccr | CCCR_INIT); udelay(5); /* CCCR.CCE can only be set/reset while CCCR.INIT = '1' */ m_can_write(cdev, M_CAN_CCCR, cccr | CCCR_INIT | CCCR_CCE); } else { m_can_write(cdev, M_CAN_CCCR, cccr & ~(CCCR_INIT | CCCR_CCE)); } /* there's a delay for module initialization */ if (enable) val = CCCR_INIT | CCCR_CCE; while ((m_can_read(cdev, M_CAN_CCCR) & (CCCR_INIT | CCCR_CCE)) != val) { if (timeout == 0) { netdev_warn(cdev->net, "Failed to init module\n"); return; } timeout--; udelay(1); } } static inline void m_can_enable_all_interrupts(struct m_can_classdev *cdev) { /* Only interrupt line 0 is used in this driver */ m_can_write(cdev, M_CAN_ILE, ILE_EINT0); } static inline void m_can_disable_all_interrupts(struct m_can_classdev *cdev) { m_can_write(cdev, M_CAN_ILE, 0x0); } /* Retrieve internal timestamp counter from TSCV.TSC, and shift it to 32-bit * width. */ static u32 m_can_get_timestamp(struct m_can_classdev *cdev) { u32 tscv; u32 tsc; tscv = m_can_read(cdev, M_CAN_TSCV); tsc = FIELD_GET(TSCV_TSC_MASK, tscv); return (tsc << 16); } static void m_can_clean(struct net_device *net) { struct m_can_classdev *cdev = netdev_priv(net); if (cdev->tx_skb) { int putidx = 0; net->stats.tx_errors++; if (cdev->version > 30) putidx = FIELD_GET(TXFQS_TFQPI_MASK, m_can_read(cdev, M_CAN_TXFQS)); can_free_echo_skb(cdev->net, putidx, NULL); cdev->tx_skb = NULL; } } /* For peripherals, pass skb to rx-offload, which will push skb from * napi. For non-peripherals, RX is done in napi already, so push * directly. timestamp is used to ensure good skb ordering in * rx-offload and is ignored for non-peripherals. */ static void m_can_receive_skb(struct m_can_classdev *cdev, struct sk_buff *skb, u32 timestamp) { if (cdev->is_peripheral) { struct net_device_stats *stats = &cdev->net->stats; int err; err = can_rx_offload_queue_sorted(&cdev->offload, skb, timestamp); if (err) stats->rx_fifo_errors++; } else { netif_receive_skb(skb); } } static int m_can_read_fifo(struct net_device *dev, u32 rxfs) { struct net_device_stats *stats = &dev->stats; struct m_can_classdev *cdev = netdev_priv(dev); struct canfd_frame *cf; struct sk_buff *skb; struct id_and_dlc fifo_header; u32 fgi; u32 timestamp = 0; int err; /* calculate the fifo get index for where to read data */ fgi = FIELD_GET(RXFS_FGI_MASK, rxfs); err = m_can_fifo_read(cdev, fgi, M_CAN_FIFO_ID, &fifo_header, 2); if (err) goto out_fail; if (fifo_header.dlc & RX_BUF_FDF) skb = alloc_canfd_skb(dev, &cf); else skb = alloc_can_skb(dev, (struct can_frame **)&cf); if (!skb) { stats->rx_dropped++; return 0; } if (fifo_header.dlc & RX_BUF_FDF) cf->len = can_fd_dlc2len((fifo_header.dlc >> 16) & 0x0F); else cf->len = can_cc_dlc2len((fifo_header.dlc >> 16) & 0x0F); if (fifo_header.id & RX_BUF_XTD) cf->can_id = (fifo_header.id & CAN_EFF_MASK) | CAN_EFF_FLAG; else cf->can_id = (fifo_header.id >> 18) & CAN_SFF_MASK; if (fifo_header.id & RX_BUF_ESI) { cf->flags |= CANFD_ESI; netdev_dbg(dev, "ESI Error\n"); } if (!(fifo_header.dlc & RX_BUF_FDF) && (fifo_header.id & RX_BUF_RTR)) { cf->can_id |= CAN_RTR_FLAG; } else { if (fifo_header.dlc & RX_BUF_BRS) cf->flags |= CANFD_BRS; err = m_can_fifo_read(cdev, fgi, M_CAN_FIFO_DATA, cf->data, DIV_ROUND_UP(cf->len, 4)); if (err) goto out_free_skb; } /* acknowledge rx fifo 0 */ m_can_write(cdev, M_CAN_RXF0A, fgi); stats->rx_packets++; stats->rx_bytes += cf->len; timestamp = FIELD_GET(RX_BUF_RXTS_MASK, fifo_header.dlc); m_can_receive_skb(cdev, skb, timestamp); return 0; out_free_skb: kfree_skb(skb); out_fail: netdev_err(dev, "FIFO read returned %d\n", err); return err; } static int m_can_do_rx_poll(struct net_device *dev, int quota) { struct m_can_classdev *cdev = netdev_priv(dev); u32 pkts = 0; u32 rxfs; int err; rxfs = m_can_read(cdev, M_CAN_RXF0S); if (!(rxfs & RXFS_FFL_MASK)) { netdev_dbg(dev, "no messages in fifo0\n"); return 0; } while ((rxfs & RXFS_FFL_MASK) && (quota > 0)) { err = m_can_read_fifo(dev, rxfs); if (err) return err; quota--; pkts++; rxfs = m_can_read(cdev, M_CAN_RXF0S); } if (pkts) can_led_event(dev, CAN_LED_EVENT_RX); return pkts; } static int m_can_handle_lost_msg(struct net_device *dev) { struct m_can_classdev *cdev = netdev_priv(dev); struct net_device_stats *stats = &dev->stats; struct sk_buff *skb; struct can_frame *frame; u32 timestamp = 0; netdev_err(dev, "msg lost in rxf0\n"); stats->rx_errors++; stats->rx_over_errors++; skb = alloc_can_err_skb(dev, &frame); if (unlikely(!skb)) return 0; frame->can_id |= CAN_ERR_CRTL; frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; if (cdev->is_peripheral) timestamp = m_can_get_timestamp(cdev); m_can_receive_skb(cdev, skb, timestamp); return 1; } static int m_can_handle_lec_err(struct net_device *dev, enum m_can_lec_type lec_type) { struct m_can_classdev *cdev = netdev_priv(dev); struct net_device_stats *stats = &dev->stats; struct can_frame *cf; struct sk_buff *skb; u32 timestamp = 0; cdev->can.can_stats.bus_error++; stats->rx_errors++; /* propagate the error condition to the CAN stack */ skb = alloc_can_err_skb(dev, &cf); if (unlikely(!skb)) return 0; /* check for 'last error code' which tells us the * type of the last error to occur on the CAN bus */ cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; switch (lec_type) { case LEC_STUFF_ERROR: netdev_dbg(dev, "stuff error\n"); cf->data[2] |= CAN_ERR_PROT_STUFF; break; case LEC_FORM_ERROR: netdev_dbg(dev, "form error\n"); cf->data[2] |= CAN_ERR_PROT_FORM; break; case LEC_ACK_ERROR: netdev_dbg(dev, "ack error\n"); cf->data[3] = CAN_ERR_PROT_LOC_ACK; break; case LEC_BIT1_ERROR: netdev_dbg(dev, "bit1 error\n"); cf->data[2] |= CAN_ERR_PROT_BIT1; break; case LEC_BIT0_ERROR: netdev_dbg(dev, "bit0 error\n"); cf->data[2] |= CAN_ERR_PROT_BIT0; break; case LEC_CRC_ERROR: netdev_dbg(dev, "CRC error\n"); cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ; break; default: break; } stats->rx_packets++; stats->rx_bytes += cf->len; if (cdev->is_peripheral) timestamp = m_can_get_timestamp(cdev); m_can_receive_skb(cdev, skb, timestamp); return 1; } static int __m_can_get_berr_counter(const struct net_device *dev, struct can_berr_counter *bec) { struct m_can_classdev *cdev = netdev_priv(dev); unsigned int ecr; ecr = m_can_read(cdev, M_CAN_ECR); bec->rxerr = FIELD_GET(ECR_REC_MASK, ecr); bec->txerr = FIELD_GET(ECR_TEC_MASK, ecr); return 0; } static int m_can_clk_start(struct m_can_classdev *cdev) { if (cdev->pm_clock_support == 0) return 0; return pm_runtime_resume_and_get(cdev->dev); } static void m_can_clk_stop(struct m_can_classdev *cdev) { if (cdev->pm_clock_support) pm_runtime_put_sync(cdev->dev); } static int m_can_get_berr_counter(const struct net_device *dev, struct can_berr_counter *bec) { struct m_can_classdev *cdev = netdev_priv(dev); int err; err = m_can_clk_start(cdev); if (err) return err; __m_can_get_berr_counter(dev, bec); m_can_clk_stop(cdev); return 0; } static int m_can_handle_state_change(struct net_device *dev, enum can_state new_state) { struct m_can_classdev *cdev = netdev_priv(dev); struct net_device_stats *stats = &dev->stats; struct can_frame *cf; struct sk_buff *skb; struct can_berr_counter bec; unsigned int ecr; u32 timestamp = 0; switch (new_state) { case CAN_STATE_ERROR_WARNING: /* error warning state */ cdev->can.can_stats.error_warning++; cdev->can.state = CAN_STATE_ERROR_WARNING; break; case CAN_STATE_ERROR_PASSIVE: /* error passive state */ cdev->can.can_stats.error_passive++; cdev->can.state = CAN_STATE_ERROR_PASSIVE; break; case CAN_STATE_BUS_OFF: /* bus-off state */ cdev->can.state = CAN_STATE_BUS_OFF; m_can_disable_all_interrupts(cdev); cdev->can.can_stats.bus_off++; can_bus_off(dev); break; default: break; } /* propagate the error condition to the CAN stack */ skb = alloc_can_err_skb(dev, &cf); if (unlikely(!skb)) return 0; __m_can_get_berr_counter(dev, &bec); switch (new_state) { case CAN_STATE_ERROR_WARNING: /* error warning state */ cf->can_id |= CAN_ERR_CRTL; cf->data[1] = (bec.txerr > bec.rxerr) ? CAN_ERR_CRTL_TX_WARNING : CAN_ERR_CRTL_RX_WARNING; cf->data[6] = bec.txerr; cf->data[7] = bec.rxerr; break; case CAN_STATE_ERROR_PASSIVE: /* error passive state */ cf->can_id |= CAN_ERR_CRTL; ecr = m_can_read(cdev, M_CAN_ECR); if (ecr & ECR_RP) cf->data[1] |= CAN_ERR_CRTL_RX_PASSIVE; if (bec.txerr > 127) cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE; cf->data[6] = bec.txerr; cf->data[7] = bec.rxerr; break; case CAN_STATE_BUS_OFF: /* bus-off state */ cf->can_id |= CAN_ERR_BUSOFF; break; default: break; } stats->rx_packets++; stats->rx_bytes += cf->len; if (cdev->is_peripheral) timestamp = m_can_get_timestamp(cdev); m_can_receive_skb(cdev, skb, timestamp); return 1; } static int m_can_handle_state_errors(struct net_device *dev, u32 psr) { struct m_can_classdev *cdev = netdev_priv(dev); int work_done = 0; if (psr & PSR_EW && cdev->can.state != CAN_STATE_ERROR_WARNING) { netdev_dbg(dev, "entered error warning state\n"); work_done += m_can_handle_state_change(dev, CAN_STATE_ERROR_WARNING); } if (psr & PSR_EP && cdev->can.state != CAN_STATE_ERROR_PASSIVE) { netdev_dbg(dev, "entered error passive state\n"); work_done += m_can_handle_state_change(dev, CAN_STATE_ERROR_PASSIVE); } if (psr & PSR_BO && cdev->can.state != CAN_STATE_BUS_OFF) { netdev_dbg(dev, "entered error bus off state\n"); work_done += m_can_handle_state_change(dev, CAN_STATE_BUS_OFF); } return work_done; } static void m_can_handle_other_err(struct net_device *dev, u32 irqstatus) { if (irqstatus & IR_WDI) netdev_err(dev, "Message RAM Watchdog event due to missing READY\n"); if (irqstatus & IR_BEU) netdev_err(dev, "Bit Error Uncorrected\n"); if (irqstatus & IR_BEC) netdev_err(dev, "Bit Error Corrected\n"); if (irqstatus & IR_TOO) netdev_err(dev, "Timeout reached\n"); if (irqstatus & IR_MRAF) netdev_err(dev, "Message RAM access failure occurred\n"); } static inline bool is_lec_err(u32 psr) { psr &= LEC_UNUSED; return psr && (psr != LEC_UNUSED); } static inline bool m_can_is_protocol_err(u32 irqstatus) { return irqstatus & IR_ERR_LEC_31X; } static int m_can_handle_protocol_error(struct net_device *dev, u32 irqstatus) { struct net_device_stats *stats = &dev->stats; struct m_can_classdev *cdev = netdev_priv(dev); struct can_frame *cf; struct sk_buff *skb; u32 timestamp = 0; /* propagate the error condition to the CAN stack */ skb = alloc_can_err_skb(dev, &cf); /* update tx error stats since there is protocol error */ stats->tx_errors++; /* update arbitration lost status */ if (cdev->version >= 31 && (irqstatus & IR_PEA)) { netdev_dbg(dev, "Protocol error in Arbitration fail\n"); cdev->can.can_stats.arbitration_lost++; if (skb) { cf->can_id |= CAN_ERR_LOSTARB; cf->data[0] |= CAN_ERR_LOSTARB_UNSPEC; } } if (unlikely(!skb)) { netdev_dbg(dev, "allocation of skb failed\n"); return 0; } if (cdev->is_peripheral) timestamp = m_can_get_timestamp(cdev); m_can_receive_skb(cdev, skb, timestamp); return 1; } static int m_can_handle_bus_errors(struct net_device *dev, u32 irqstatus, u32 psr) { struct m_can_classdev *cdev = netdev_priv(dev); int work_done = 0; if (irqstatus & IR_RF0L) work_done += m_can_handle_lost_msg(dev); /* handle lec errors on the bus */ if ((cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) && is_lec_err(psr)) work_done += m_can_handle_lec_err(dev, psr & LEC_UNUSED); /* handle protocol errors in arbitration phase */ if ((cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) && m_can_is_protocol_err(irqstatus)) work_done += m_can_handle_protocol_error(dev, irqstatus); /* other unproccessed error interrupts */ m_can_handle_other_err(dev, irqstatus); return work_done; } static int m_can_rx_handler(struct net_device *dev, int quota) { struct m_can_classdev *cdev = netdev_priv(dev); int rx_work_or_err; int work_done = 0; u32 irqstatus, psr; irqstatus = cdev->irqstatus | m_can_read(cdev, M_CAN_IR); if (!irqstatus) goto end; /* Errata workaround for issue "Needless activation of MRAF irq" * During frame reception while the MCAN is in Error Passive state * and the Receive Error Counter has the value MCAN_ECR.REC = 127, * it may happen that MCAN_IR.MRAF is set although there was no * Message RAM access failure. * If MCAN_IR.MRAF is enabled, an interrupt to the Host CPU is generated * The Message RAM Access Failure interrupt routine needs to check * whether MCAN_ECR.RP = ’1’ and MCAN_ECR.REC = 127. * In this case, reset MCAN_IR.MRAF. No further action is required. */ if (cdev->version <= 31 && irqstatus & IR_MRAF && m_can_read(cdev, M_CAN_ECR) & ECR_RP) { struct can_berr_counter bec; __m_can_get_berr_counter(dev, &bec); if (bec.rxerr == 127) { m_can_write(cdev, M_CAN_IR, IR_MRAF); irqstatus &= ~IR_MRAF; } } psr = m_can_read(cdev, M_CAN_PSR); if (irqstatus & IR_ERR_STATE) work_done += m_can_handle_state_errors(dev, psr); if (irqstatus & IR_ERR_BUS_30X) work_done += m_can_handle_bus_errors(dev, irqstatus, psr); if (irqstatus & IR_RF0N) { rx_work_or_err = m_can_do_rx_poll(dev, (quota - work_done)); if (rx_work_or_err < 0) return rx_work_or_err; work_done += rx_work_or_err; } end: return work_done; } static int m_can_rx_peripheral(struct net_device *dev) { struct m_can_classdev *cdev = netdev_priv(dev); int work_done; work_done = m_can_rx_handler(dev, M_CAN_NAPI_WEIGHT); /* Don't re-enable interrupts if the driver had a fatal error * (e.g., FIFO read failure). */ if (work_done >= 0) m_can_enable_all_interrupts(cdev); return work_done; } static int m_can_poll(struct napi_struct *napi, int quota) { struct net_device *dev = napi->dev; struct m_can_classdev *cdev = netdev_priv(dev); int work_done; work_done = m_can_rx_handler(dev, quota); /* Don't re-enable interrupts if the driver had a fatal error * (e.g., FIFO read failure). */ if (work_done >= 0 && work_done < quota) { napi_complete_done(napi, work_done); m_can_enable_all_interrupts(cdev); } return work_done; } /* Echo tx skb and update net stats. Peripherals use rx-offload for * echo. timestamp is used for peripherals to ensure correct ordering * by rx-offload, and is ignored for non-peripherals. */ static void m_can_tx_update_stats(struct m_can_classdev *cdev, unsigned int msg_mark, u32 timestamp) { struct net_device *dev = cdev->net; struct net_device_stats *stats = &dev->stats; if (cdev->is_peripheral) stats->tx_bytes += can_rx_offload_get_echo_skb(&cdev->offload, msg_mark, timestamp, NULL); else stats->tx_bytes += can_get_echo_skb(dev, msg_mark, NULL); stats->tx_packets++; } static int m_can_echo_tx_event(struct net_device *dev) { u32 txe_count = 0; u32 m_can_txefs; u32 fgi = 0; int i = 0; unsigned int msg_mark; struct m_can_classdev *cdev = netdev_priv(dev); /* read tx event fifo status */ m_can_txefs = m_can_read(cdev, M_CAN_TXEFS); /* Get Tx Event fifo element count */ txe_count = FIELD_GET(TXEFS_EFFL_MASK, m_can_txefs); /* Get and process all sent elements */ for (i = 0; i < txe_count; i++) { u32 txe, timestamp = 0; int err; /* retrieve get index */ fgi = FIELD_GET(TXEFS_EFGI_MASK, m_can_read(cdev, M_CAN_TXEFS)); /* get message marker, timestamp */ err = m_can_txe_fifo_read(cdev, fgi, 4, &txe); if (err) { netdev_err(dev, "TXE FIFO read returned %d\n", err); return err; } msg_mark = FIELD_GET(TX_EVENT_MM_MASK, txe); timestamp = FIELD_GET(TX_EVENT_TXTS_MASK, txe); /* ack txe element */ m_can_write(cdev, M_CAN_TXEFA, FIELD_PREP(TXEFA_EFAI_MASK, fgi)); /* update stats */ m_can_tx_update_stats(cdev, msg_mark, timestamp); } return 0; } static irqreturn_t m_can_isr(int irq, void *dev_id) { struct net_device *dev = (struct net_device *)dev_id; struct m_can_classdev *cdev = netdev_priv(dev); u32 ir; if (pm_runtime_suspended(cdev->dev)) return IRQ_NONE; ir = m_can_read(cdev, M_CAN_IR); if (!ir) return IRQ_NONE; /* ACK all irqs */ if (ir & IR_ALL_INT) m_can_write(cdev, M_CAN_IR, ir); if (cdev->ops->clear_interrupts) cdev->ops->clear_interrupts(cdev); /* schedule NAPI in case of * - rx IRQ * - state change IRQ * - bus error IRQ and bus error reporting */ if ((ir & IR_RF0N) || (ir & IR_ERR_ALL_30X)) { cdev->irqstatus = ir; m_can_disable_all_interrupts(cdev); if (!cdev->is_peripheral) napi_schedule(&cdev->napi); else if (m_can_rx_peripheral(dev) < 0) goto out_fail; } if (cdev->version == 30) { if (ir & IR_TC) { /* Transmission Complete Interrupt*/ u32 timestamp = 0; if (cdev->is_peripheral) timestamp = m_can_get_timestamp(cdev); m_can_tx_update_stats(cdev, 0, timestamp); can_led_event(dev, CAN_LED_EVENT_TX); netif_wake_queue(dev); } } else { if (ir & IR_TEFN) { /* New TX FIFO Element arrived */ if (m_can_echo_tx_event(dev) != 0) goto out_fail; can_led_event(dev, CAN_LED_EVENT_TX); if (netif_queue_stopped(dev) && !m_can_tx_fifo_full(cdev)) netif_wake_queue(dev); } } if (cdev->is_peripheral) can_rx_offload_threaded_irq_finish(&cdev->offload); return IRQ_HANDLED; out_fail: m_can_disable_all_interrupts(cdev); return IRQ_HANDLED; } static const struct can_bittiming_const m_can_bittiming_const_30X = { .name = KBUILD_MODNAME, .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */ .tseg1_max = 64, .tseg2_min = 1, /* Time segment 2 = phase_seg2 */ .tseg2_max = 16, .sjw_max = 16, .brp_min = 1, .brp_max = 1024, .brp_inc = 1, }; static const struct can_bittiming_const m_can_data_bittiming_const_30X = { .name = KBUILD_MODNAME, .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */ .tseg1_max = 16, .tseg2_min = 1, /* Time segment 2 = phase_seg2 */ .tseg2_max = 8, .sjw_max = 4, .brp_min = 1, .brp_max = 32, .brp_inc = 1, }; static const struct can_bittiming_const m_can_bittiming_const_31X = { .name = KBUILD_MODNAME, .tseg1_min = 2, /* Time segment 1 = prop_seg + phase_seg1 */ .tseg1_max = 256, .tseg2_min = 2, /* Time segment 2 = phase_seg2 */ .tseg2_max = 128, .sjw_max = 128, .brp_min = 1, .brp_max = 512, .brp_inc = 1, }; static const struct can_bittiming_const m_can_data_bittiming_const_31X = { .name = KBUILD_MODNAME, .tseg1_min = 1, /* Time segment 1 = prop_seg + phase_seg1 */ .tseg1_max = 32, .tseg2_min = 1, /* Time segment 2 = phase_seg2 */ .tseg2_max = 16, .sjw_max = 16, .brp_min = 1, .brp_max = 32, .brp_inc = 1, }; static int m_can_set_bittiming(struct net_device *dev) { struct m_can_classdev *cdev = netdev_priv(dev); const struct can_bittiming *bt = &cdev->can.bittiming; const struct can_bittiming *dbt = &cdev->can.data_bittiming; u16 brp, sjw, tseg1, tseg2; u32 reg_btp; brp = bt->brp - 1; sjw = bt->sjw - 1; tseg1 = bt->prop_seg + bt->phase_seg1 - 1; tseg2 = bt->phase_seg2 - 1; reg_btp = FIELD_PREP(NBTP_NBRP_MASK, brp) | FIELD_PREP(NBTP_NSJW_MASK, sjw) | FIELD_PREP(NBTP_NTSEG1_MASK, tseg1) | FIELD_PREP(NBTP_NTSEG2_MASK, tseg2); m_can_write(cdev, M_CAN_NBTP, reg_btp); if (cdev->can.ctrlmode & CAN_CTRLMODE_FD) { reg_btp = 0; brp = dbt->brp - 1; sjw = dbt->sjw - 1; tseg1 = dbt->prop_seg + dbt->phase_seg1 - 1; tseg2 = dbt->phase_seg2 - 1; /* TDC is only needed for bitrates beyond 2.5 MBit/s. * This is mentioned in the "Bit Time Requirements for CAN FD" * paper presented at the International CAN Conference 2013 */ if (dbt->bitrate > 2500000) { u32 tdco, ssp; /* Use the same value of secondary sampling point * as the data sampling point */ ssp = dbt->sample_point; /* Equation based on Bosch's M_CAN User Manual's * Transmitter Delay Compensation Section */ tdco = (cdev->can.clock.freq / 1000) * ssp / dbt->bitrate; /* Max valid TDCO value is 127 */ if (tdco > 127) { netdev_warn(dev, "TDCO value of %u is beyond maximum. Using maximum possible value\n", tdco); tdco = 127; } reg_btp |= DBTP_TDC; m_can_write(cdev, M_CAN_TDCR, FIELD_PREP(TDCR_TDCO_MASK, tdco)); } reg_btp |= FIELD_PREP(DBTP_DBRP_MASK, brp) | FIELD_PREP(DBTP_DSJW_MASK, sjw) | FIELD_PREP(DBTP_DTSEG1_MASK, tseg1) | FIELD_PREP(DBTP_DTSEG2_MASK, tseg2); m_can_write(cdev, M_CAN_DBTP, reg_btp); } return 0; } /* Configure M_CAN chip: * - set rx buffer/fifo element size * - configure rx fifo * - accept non-matching frame into fifo 0 * - configure tx buffer * - >= v3.1.x: TX FIFO is used * - configure mode * - setup bittiming * - configure timestamp generation */ static void m_can_chip_config(struct net_device *dev) { struct m_can_classdev *cdev = netdev_priv(dev); u32 cccr, test; m_can_config_endisable(cdev, true); /* RX Buffer/FIFO Element Size 64 bytes data field */ m_can_write(cdev, M_CAN_RXESC, FIELD_PREP(RXESC_RBDS_MASK, RXESC_64B) | FIELD_PREP(RXESC_F1DS_MASK, RXESC_64B) | FIELD_PREP(RXESC_F0DS_MASK, RXESC_64B)); /* Accept Non-matching Frames Into FIFO 0 */ m_can_write(cdev, M_CAN_GFC, 0x0); if (cdev->version == 30) { /* only support one Tx Buffer currently */ m_can_write(cdev, M_CAN_TXBC, FIELD_PREP(TXBC_NDTB_MASK, 1) | cdev->mcfg[MRAM_TXB].off); } else { /* TX FIFO is used for newer IP Core versions */ m_can_write(cdev, M_CAN_TXBC, FIELD_PREP(TXBC_TFQS_MASK, cdev->mcfg[MRAM_TXB].num) | cdev->mcfg[MRAM_TXB].off); } /* support 64 bytes payload */ m_can_write(cdev, M_CAN_TXESC, FIELD_PREP(TXESC_TBDS_MASK, TXESC_TBDS_64B)); /* TX Event FIFO */ if (cdev->version == 30) { m_can_write(cdev, M_CAN_TXEFC, FIELD_PREP(TXEFC_EFS_MASK, 1) | cdev->mcfg[MRAM_TXE].off); } else { /* Full TX Event FIFO is used */ m_can_write(cdev, M_CAN_TXEFC, FIELD_PREP(TXEFC_EFS_MASK, cdev->mcfg[MRAM_TXE].num) | cdev->mcfg[MRAM_TXE].off); } /* rx fifo configuration, blocking mode, fifo size 1 */ m_can_write(cdev, M_CAN_RXF0C, FIELD_PREP(RXFC_FS_MASK, cdev->mcfg[MRAM_RXF0].num) | cdev->mcfg[MRAM_RXF0].off); m_can_write(cdev, M_CAN_RXF1C, FIELD_PREP(RXFC_FS_MASK, cdev->mcfg[MRAM_RXF1].num) | cdev->mcfg[MRAM_RXF1].off); cccr = m_can_read(cdev, M_CAN_CCCR); test = m_can_read(cdev, M_CAN_TEST); test &= ~TEST_LBCK; if (cdev->version == 30) { /* Version 3.0.x */ cccr &= ~(CCCR_TEST | CCCR_MON | CCCR_DAR | FIELD_PREP(CCCR_CMR_MASK, FIELD_MAX(CCCR_CMR_MASK)) | FIELD_PREP(CCCR_CME_MASK, FIELD_MAX(CCCR_CME_MASK))); if (cdev->can.ctrlmode & CAN_CTRLMODE_FD) cccr |= FIELD_PREP(CCCR_CME_MASK, CCCR_CME_CANFD_BRS); } else { /* Version 3.1.x or 3.2.x */ cccr &= ~(CCCR_TEST | CCCR_MON | CCCR_BRSE | CCCR_FDOE | CCCR_NISO | CCCR_DAR); /* Only 3.2.x has NISO Bit implemented */ if (cdev->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO) cccr |= CCCR_NISO; if (cdev->can.ctrlmode & CAN_CTRLMODE_FD) cccr |= (CCCR_BRSE | CCCR_FDOE); } /* Loopback Mode */ if (cdev->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) { cccr |= CCCR_TEST | CCCR_MON; test |= TEST_LBCK; } /* Enable Monitoring (all versions) */ if (cdev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY) cccr |= CCCR_MON; /* Disable Auto Retransmission (all versions) */ if (cdev->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT) cccr |= CCCR_DAR; /* Write config */ m_can_write(cdev, M_CAN_CCCR, cccr); m_can_write(cdev, M_CAN_TEST, test); /* Enable interrupts */ m_can_write(cdev, M_CAN_IR, IR_ALL_INT); if (!(cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)) if (cdev->version == 30) m_can_write(cdev, M_CAN_IE, IR_ALL_INT & ~(IR_ERR_LEC_30X)); else m_can_write(cdev, M_CAN_IE, IR_ALL_INT & ~(IR_ERR_LEC_31X)); else m_can_write(cdev, M_CAN_IE, IR_ALL_INT); /* route all interrupts to INT0 */ m_can_write(cdev, M_CAN_ILS, ILS_ALL_INT0); /* set bittiming params */ m_can_set_bittiming(dev); /* enable internal timestamp generation, with a prescalar of 16. The * prescalar is applied to the nominal bit timing */ m_can_write(cdev, M_CAN_TSCC, FIELD_PREP(TSCC_TCP_MASK, 0xf)); m_can_config_endisable(cdev, false); if (cdev->ops->init) cdev->ops->init(cdev); } static void m_can_start(struct net_device *dev) { struct m_can_classdev *cdev = netdev_priv(dev); /* basic m_can configuration */ m_can_chip_config(dev); cdev->can.state = CAN_STATE_ERROR_ACTIVE; m_can_enable_all_interrupts(cdev); } static int m_can_set_mode(struct net_device *dev, enum can_mode mode) { switch (mode) { case CAN_MODE_START: m_can_clean(dev); m_can_start(dev); netif_wake_queue(dev); break; default: return -EOPNOTSUPP; } return 0; } /* Checks core release number of M_CAN * returns 0 if an unsupported device is detected * else it returns the release and step coded as: * return value = 10 * + 1 * */ static int m_can_check_core_release(struct m_can_classdev *cdev) { u32 crel_reg; u8 rel; u8 step; int res; /* Read Core Release Version and split into version number * Example: Version 3.2.1 => rel = 3; step = 2; substep = 1; */ crel_reg = m_can_read(cdev, M_CAN_CREL); rel = (u8)FIELD_GET(CREL_REL_MASK, crel_reg); step = (u8)FIELD_GET(CREL_STEP_MASK, crel_reg); if (rel == 3) { /* M_CAN v3.x.y: create return value */ res = 30 + step; } else { /* Unsupported M_CAN version */ res = 0; } return res; } /* Selectable Non ISO support only in version 3.2.x * This function checks if the bit is writable. */ static bool m_can_niso_supported(struct m_can_classdev *cdev) { u32 cccr_reg, cccr_poll = 0; int niso_timeout = -ETIMEDOUT; int i; m_can_config_endisable(cdev, true); cccr_reg = m_can_read(cdev, M_CAN_CCCR); cccr_reg |= CCCR_NISO; m_can_write(cdev, M_CAN_CCCR, cccr_reg); for (i = 0; i <= 10; i++) { cccr_poll = m_can_read(cdev, M_CAN_CCCR); if (cccr_poll == cccr_reg) { niso_timeout = 0; break; } usleep_range(1, 5); } /* Clear NISO */ cccr_reg &= ~(CCCR_NISO); m_can_write(cdev, M_CAN_CCCR, cccr_reg); m_can_config_endisable(cdev, false); /* return false if time out (-ETIMEDOUT), else return true */ return !niso_timeout; } static int m_can_dev_setup(struct m_can_classdev *cdev) { struct net_device *dev = cdev->net; int m_can_version; m_can_version = m_can_check_core_release(cdev); /* return if unsupported version */ if (!m_can_version) { dev_err(cdev->dev, "Unsupported version number: %2d", m_can_version); return -EINVAL; } if (!cdev->is_peripheral) netif_napi_add(dev, &cdev->napi, m_can_poll, M_CAN_NAPI_WEIGHT); /* Shared properties of all M_CAN versions */ cdev->version = m_can_version; cdev->can.do_set_mode = m_can_set_mode; cdev->can.do_get_berr_counter = m_can_get_berr_counter; /* Set M_CAN supported operations */ cdev->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK | CAN_CTRLMODE_LISTENONLY | CAN_CTRLMODE_BERR_REPORTING | CAN_CTRLMODE_FD | CAN_CTRLMODE_ONE_SHOT; /* Set properties depending on M_CAN version */ switch (cdev->version) { case 30: /* CAN_CTRLMODE_FD_NON_ISO is fixed with M_CAN IP v3.0.x */ can_set_static_ctrlmode(dev, CAN_CTRLMODE_FD_NON_ISO); cdev->can.bittiming_const = cdev->bit_timing ? cdev->bit_timing : &m_can_bittiming_const_30X; cdev->can.data_bittiming_const = cdev->data_timing ? cdev->data_timing : &m_can_data_bittiming_const_30X; break; case 31: /* CAN_CTRLMODE_FD_NON_ISO is fixed with M_CAN IP v3.1.x */ can_set_static_ctrlmode(dev, CAN_CTRLMODE_FD_NON_ISO); cdev->can.bittiming_const = cdev->bit_timing ? cdev->bit_timing : &m_can_bittiming_const_31X; cdev->can.data_bittiming_const = cdev->data_timing ? cdev->data_timing : &m_can_data_bittiming_const_31X; break; case 32: case 33: /* Support both MCAN version v3.2.x and v3.3.0 */ cdev->can.bittiming_const = cdev->bit_timing ? cdev->bit_timing : &m_can_bittiming_const_31X; cdev->can.data_bittiming_const = cdev->data_timing ? cdev->data_timing : &m_can_data_bittiming_const_31X; cdev->can.ctrlmode_supported |= (m_can_niso_supported(cdev) ? CAN_CTRLMODE_FD_NON_ISO : 0); break; default: dev_err(cdev->dev, "Unsupported version number: %2d", cdev->version); return -EINVAL; } if (cdev->ops->init) cdev->ops->init(cdev); return 0; } static void m_can_stop(struct net_device *dev) { struct m_can_classdev *cdev = netdev_priv(dev); /* disable all interrupts */ m_can_disable_all_interrupts(cdev); /* Set init mode to disengage from the network */ m_can_config_endisable(cdev, true); /* set the state as STOPPED */ cdev->can.state = CAN_STATE_STOPPED; } static int m_can_close(struct net_device *dev) { struct m_can_classdev *cdev = netdev_priv(dev); netif_stop_queue(dev); if (!cdev->is_peripheral) napi_disable(&cdev->napi); m_can_stop(dev); m_can_clk_stop(cdev); free_irq(dev->irq, dev); if (cdev->is_peripheral) { cdev->tx_skb = NULL; destroy_workqueue(cdev->tx_wq); cdev->tx_wq = NULL; } if (cdev->is_peripheral) can_rx_offload_disable(&cdev->offload); close_candev(dev); can_led_event(dev, CAN_LED_EVENT_STOP); phy_power_off(cdev->transceiver); return 0; } static int m_can_next_echo_skb_occupied(struct net_device *dev, int putidx) { struct m_can_classdev *cdev = netdev_priv(dev); /*get wrap around for loopback skb index */ unsigned int wrap = cdev->can.echo_skb_max; int next_idx; /* calculate next index */ next_idx = (++putidx >= wrap ? 0 : putidx); /* check if occupied */ return !!cdev->can.echo_skb[next_idx]; } static netdev_tx_t m_can_tx_handler(struct m_can_classdev *cdev) { struct canfd_frame *cf = (struct canfd_frame *)cdev->tx_skb->data; struct net_device *dev = cdev->net; struct sk_buff *skb = cdev->tx_skb; struct id_and_dlc fifo_header; u32 cccr, fdflags; int err; int putidx; cdev->tx_skb = NULL; /* Generate ID field for TX buffer Element */ /* Common to all supported M_CAN versions */ if (cf->can_id & CAN_EFF_FLAG) { fifo_header.id = cf->can_id & CAN_EFF_MASK; fifo_header.id |= TX_BUF_XTD; } else { fifo_header.id = ((cf->can_id & CAN_SFF_MASK) << 18); } if (cf->can_id & CAN_RTR_FLAG) fifo_header.id |= TX_BUF_RTR; if (cdev->version == 30) { netif_stop_queue(dev); fifo_header.dlc = can_fd_len2dlc(cf->len) << 16; /* Write the frame ID, DLC, and payload to the FIFO element. */ err = m_can_fifo_write(cdev, 0, M_CAN_FIFO_ID, &fifo_header, 2); if (err) goto out_fail; err = m_can_fifo_write(cdev, 0, M_CAN_FIFO_DATA, cf->data, DIV_ROUND_UP(cf->len, 4)); if (err) goto out_fail; can_put_echo_skb(skb, dev, 0, 0); if (cdev->can.ctrlmode & CAN_CTRLMODE_FD) { cccr = m_can_read(cdev, M_CAN_CCCR); cccr &= ~CCCR_CMR_MASK; if (can_is_canfd_skb(skb)) { if (cf->flags & CANFD_BRS) cccr |= FIELD_PREP(CCCR_CMR_MASK, CCCR_CMR_CANFD_BRS); else cccr |= FIELD_PREP(CCCR_CMR_MASK, CCCR_CMR_CANFD); } else { cccr |= FIELD_PREP(CCCR_CMR_MASK, CCCR_CMR_CAN); } m_can_write(cdev, M_CAN_CCCR, cccr); } m_can_write(cdev, M_CAN_TXBTIE, 0x1); m_can_write(cdev, M_CAN_TXBAR, 0x1); /* End of xmit function for version 3.0.x */ } else { /* Transmit routine for version >= v3.1.x */ /* Check if FIFO full */ if (m_can_tx_fifo_full(cdev)) { /* This shouldn't happen */ netif_stop_queue(dev); netdev_warn(dev, "TX queue active although FIFO is full."); if (cdev->is_peripheral) { kfree_skb(skb); dev->stats.tx_dropped++; return NETDEV_TX_OK; } else { return NETDEV_TX_BUSY; } } /* get put index for frame */ putidx = FIELD_GET(TXFQS_TFQPI_MASK, m_can_read(cdev, M_CAN_TXFQS)); /* Construct DLC Field, with CAN-FD configuration. * Use the put index of the fifo as the message marker, * used in the TX interrupt for sending the correct echo frame. */ /* get CAN FD configuration of frame */ fdflags = 0; if (can_is_canfd_skb(skb)) { fdflags |= TX_BUF_FDF; if (cf->flags & CANFD_BRS) fdflags |= TX_BUF_BRS; } fifo_header.dlc = FIELD_PREP(TX_BUF_MM_MASK, putidx) | FIELD_PREP(TX_BUF_DLC_MASK, can_fd_len2dlc(cf->len)) | fdflags | TX_BUF_EFC; err = m_can_fifo_write(cdev, putidx, M_CAN_FIFO_ID, &fifo_header, 2); if (err) goto out_fail; err = m_can_fifo_write(cdev, putidx, M_CAN_FIFO_DATA, cf->data, DIV_ROUND_UP(cf->len, 4)); if (err) goto out_fail; /* Push loopback echo. * Will be looped back on TX interrupt based on message marker */ can_put_echo_skb(skb, dev, putidx, 0); /* Enable TX FIFO element to start transfer */ m_can_write(cdev, M_CAN_TXBAR, (1 << putidx)); /* stop network queue if fifo full */ if (m_can_tx_fifo_full(cdev) || m_can_next_echo_skb_occupied(dev, putidx)) netif_stop_queue(dev); } return NETDEV_TX_OK; out_fail: netdev_err(dev, "FIFO write returned %d\n", err); m_can_disable_all_interrupts(cdev); return NETDEV_TX_BUSY; } static void m_can_tx_work_queue(struct work_struct *ws) { struct m_can_classdev *cdev = container_of(ws, struct m_can_classdev, tx_work); m_can_tx_handler(cdev); } static netdev_tx_t m_can_start_xmit(struct sk_buff *skb, struct net_device *dev) { struct m_can_classdev *cdev = netdev_priv(dev); if (can_dropped_invalid_skb(dev, skb)) return NETDEV_TX_OK; if (cdev->is_peripheral) { if (cdev->tx_skb) { netdev_err(dev, "hard_xmit called while tx busy\n"); return NETDEV_TX_BUSY; } if (cdev->can.state == CAN_STATE_BUS_OFF) { m_can_clean(dev); } else { /* Need to stop the queue to avoid numerous requests * from being sent. Suggested improvement is to create * a queueing mechanism that will queue the skbs and * process them in order. */ cdev->tx_skb = skb; netif_stop_queue(cdev->net); queue_work(cdev->tx_wq, &cdev->tx_work); } } else { cdev->tx_skb = skb; return m_can_tx_handler(cdev); } return NETDEV_TX_OK; } static int m_can_open(struct net_device *dev) { struct m_can_classdev *cdev = netdev_priv(dev); int err; err = phy_power_on(cdev->transceiver); if (err) return err; err = m_can_clk_start(cdev); if (err) goto out_phy_power_off; /* open the can device */ err = open_candev(dev); if (err) { netdev_err(dev, "failed to open can device\n"); goto exit_disable_clks; } if (cdev->is_peripheral) can_rx_offload_enable(&cdev->offload); /* register interrupt handler */ if (cdev->is_peripheral) { cdev->tx_skb = NULL; cdev->tx_wq = alloc_workqueue("mcan_wq", WQ_FREEZABLE | WQ_MEM_RECLAIM, 0); if (!cdev->tx_wq) { err = -ENOMEM; goto out_wq_fail; } INIT_WORK(&cdev->tx_work, m_can_tx_work_queue); err = request_threaded_irq(dev->irq, NULL, m_can_isr, IRQF_ONESHOT, dev->name, dev); } else { err = request_irq(dev->irq, m_can_isr, IRQF_SHARED, dev->name, dev); } if (err < 0) { netdev_err(dev, "failed to request interrupt\n"); goto exit_irq_fail; } /* start the m_can controller */ m_can_start(dev); can_led_event(dev, CAN_LED_EVENT_OPEN); if (!cdev->is_peripheral) napi_enable(&cdev->napi); netif_start_queue(dev); return 0; exit_irq_fail: if (cdev->is_peripheral) destroy_workqueue(cdev->tx_wq); out_wq_fail: if (cdev->is_peripheral) can_rx_offload_disable(&cdev->offload); close_candev(dev); exit_disable_clks: m_can_clk_stop(cdev); out_phy_power_off: phy_power_off(cdev->transceiver); return err; } static const struct net_device_ops m_can_netdev_ops = { .ndo_open = m_can_open, .ndo_stop = m_can_close, .ndo_start_xmit = m_can_start_xmit, .ndo_change_mtu = can_change_mtu, }; static int register_m_can_dev(struct net_device *dev) { dev->flags |= IFF_ECHO; /* we support local echo */ dev->netdev_ops = &m_can_netdev_ops; return register_candev(dev); } static void m_can_of_parse_mram(struct m_can_classdev *cdev, const u32 *mram_config_vals) { cdev->mcfg[MRAM_SIDF].off = mram_config_vals[0]; cdev->mcfg[MRAM_SIDF].num = mram_config_vals[1]; cdev->mcfg[MRAM_XIDF].off = cdev->mcfg[MRAM_SIDF].off + cdev->mcfg[MRAM_SIDF].num * SIDF_ELEMENT_SIZE; cdev->mcfg[MRAM_XIDF].num = mram_config_vals[2]; cdev->mcfg[MRAM_RXF0].off = cdev->mcfg[MRAM_XIDF].off + cdev->mcfg[MRAM_XIDF].num * XIDF_ELEMENT_SIZE; cdev->mcfg[MRAM_RXF0].num = mram_config_vals[3] & FIELD_MAX(RXFC_FS_MASK); cdev->mcfg[MRAM_RXF1].off = cdev->mcfg[MRAM_RXF0].off + cdev->mcfg[MRAM_RXF0].num * RXF0_ELEMENT_SIZE; cdev->mcfg[MRAM_RXF1].num = mram_config_vals[4] & FIELD_MAX(RXFC_FS_MASK); cdev->mcfg[MRAM_RXB].off = cdev->mcfg[MRAM_RXF1].off + cdev->mcfg[MRAM_RXF1].num * RXF1_ELEMENT_SIZE; cdev->mcfg[MRAM_RXB].num = mram_config_vals[5]; cdev->mcfg[MRAM_TXE].off = cdev->mcfg[MRAM_RXB].off + cdev->mcfg[MRAM_RXB].num * RXB_ELEMENT_SIZE; cdev->mcfg[MRAM_TXE].num = mram_config_vals[6]; cdev->mcfg[MRAM_TXB].off = cdev->mcfg[MRAM_TXE].off + cdev->mcfg[MRAM_TXE].num * TXE_ELEMENT_SIZE; cdev->mcfg[MRAM_TXB].num = mram_config_vals[7] & FIELD_MAX(TXBC_NDTB_MASK); dev_dbg(cdev->dev, "sidf 0x%x %d xidf 0x%x %d rxf0 0x%x %d rxf1 0x%x %d rxb 0x%x %d txe 0x%x %d txb 0x%x %d\n", cdev->mcfg[MRAM_SIDF].off, cdev->mcfg[MRAM_SIDF].num, cdev->mcfg[MRAM_XIDF].off, cdev->mcfg[MRAM_XIDF].num, cdev->mcfg[MRAM_RXF0].off, cdev->mcfg[MRAM_RXF0].num, cdev->mcfg[MRAM_RXF1].off, cdev->mcfg[MRAM_RXF1].num, cdev->mcfg[MRAM_RXB].off, cdev->mcfg[MRAM_RXB].num, cdev->mcfg[MRAM_TXE].off, cdev->mcfg[MRAM_TXE].num, cdev->mcfg[MRAM_TXB].off, cdev->mcfg[MRAM_TXB].num); } int m_can_init_ram(struct m_can_classdev *cdev) { int end, i, start; int err = 0; /* initialize the entire Message RAM in use to avoid possible * ECC/parity checksum errors when reading an uninitialized buffer */ start = cdev->mcfg[MRAM_SIDF].off; end = cdev->mcfg[MRAM_TXB].off + cdev->mcfg[MRAM_TXB].num * TXB_ELEMENT_SIZE; for (i = start; i < end; i += 4) { err = m_can_fifo_write_no_off(cdev, i, 0x0); if (err) break; } return err; } EXPORT_SYMBOL_GPL(m_can_init_ram); int m_can_class_get_clocks(struct m_can_classdev *cdev) { int ret = 0; cdev->hclk = devm_clk_get(cdev->dev, "hclk"); cdev->cclk = devm_clk_get(cdev->dev, "cclk"); if (IS_ERR(cdev->cclk)) { dev_err(cdev->dev, "no clock found\n"); ret = -ENODEV; } return ret; } EXPORT_SYMBOL_GPL(m_can_class_get_clocks); struct m_can_classdev *m_can_class_allocate_dev(struct device *dev, int sizeof_priv) { struct m_can_classdev *class_dev = NULL; u32 mram_config_vals[MRAM_CFG_LEN]; struct net_device *net_dev; u32 tx_fifo_size; int ret; ret = fwnode_property_read_u32_array(dev_fwnode(dev), "bosch,mram-cfg", mram_config_vals, sizeof(mram_config_vals) / 4); if (ret) { dev_err(dev, "Could not get Message RAM configuration."); goto out; } /* Get TX FIFO size * Defines the total amount of echo buffers for loopback */ tx_fifo_size = mram_config_vals[7]; /* allocate the m_can device */ net_dev = alloc_candev(sizeof_priv, tx_fifo_size); if (!net_dev) { dev_err(dev, "Failed to allocate CAN device"); goto out; } class_dev = netdev_priv(net_dev); class_dev->net = net_dev; class_dev->dev = dev; SET_NETDEV_DEV(net_dev, dev); m_can_of_parse_mram(class_dev, mram_config_vals); out: return class_dev; } EXPORT_SYMBOL_GPL(m_can_class_allocate_dev); void m_can_class_free_dev(struct net_device *net) { free_candev(net); } EXPORT_SYMBOL_GPL(m_can_class_free_dev); int m_can_class_register(struct m_can_classdev *cdev) { int ret; if (cdev->pm_clock_support) { ret = m_can_clk_start(cdev); if (ret) return ret; } if (cdev->is_peripheral) { ret = can_rx_offload_add_manual(cdev->net, &cdev->offload, M_CAN_NAPI_WEIGHT); if (ret) goto clk_disable; } ret = m_can_dev_setup(cdev); if (ret) goto rx_offload_del; ret = register_m_can_dev(cdev->net); if (ret) { dev_err(cdev->dev, "registering %s failed (err=%d)\n", cdev->net->name, ret); goto rx_offload_del; } devm_can_led_init(cdev->net); of_can_transceiver(cdev->net); dev_info(cdev->dev, "%s device registered (irq=%d, version=%d)\n", KBUILD_MODNAME, cdev->net->irq, cdev->version); /* Probe finished * Stop clocks. They will be reactivated once the M_CAN device is opened */ m_can_clk_stop(cdev); return 0; rx_offload_del: if (cdev->is_peripheral) can_rx_offload_del(&cdev->offload); clk_disable: m_can_clk_stop(cdev); return ret; } EXPORT_SYMBOL_GPL(m_can_class_register); void m_can_class_unregister(struct m_can_classdev *cdev) { if (cdev->is_peripheral) can_rx_offload_del(&cdev->offload); unregister_candev(cdev->net); } EXPORT_SYMBOL_GPL(m_can_class_unregister); int m_can_class_suspend(struct device *dev) { struct m_can_classdev *cdev = dev_get_drvdata(dev); struct net_device *ndev = cdev->net; if (netif_running(ndev)) { netif_stop_queue(ndev); netif_device_detach(ndev); m_can_stop(ndev); m_can_clk_stop(cdev); } pinctrl_pm_select_sleep_state(dev); cdev->can.state = CAN_STATE_SLEEPING; return 0; } EXPORT_SYMBOL_GPL(m_can_class_suspend); int m_can_class_resume(struct device *dev) { struct m_can_classdev *cdev = dev_get_drvdata(dev); struct net_device *ndev = cdev->net; pinctrl_pm_select_default_state(dev); cdev->can.state = CAN_STATE_ERROR_ACTIVE; if (netif_running(ndev)) { int ret; ret = m_can_clk_start(cdev); if (ret) return ret; m_can_init_ram(cdev); m_can_start(ndev); netif_device_attach(ndev); netif_start_queue(ndev); } return 0; } EXPORT_SYMBOL_GPL(m_can_class_resume); MODULE_AUTHOR("Dong Aisheng "); MODULE_AUTHOR("Dan Murphy "); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("CAN bus driver for Bosch M_CAN controller");