Add ECC support for Xilinx CAN Controller, so this driver reports 1bit/2bit ECC errors for FIFO's based on ECC error interrupt. ECC feature for Xilinx CAN Controller selected through 'xlnx,has-ecc' DT property Signed-off-by: Srinivas Goud <srinivas.goud@xxxxxxx> --- Changes in v5: Address review comments Change the sequence of updates the stats Use u64 stats helper function Changes in v4: None Changes in v3: None Changes in v2: Address review comments drivers/net/can/xilinx_can.c | 105 +++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 101 insertions(+), 4 deletions(-) diff --git a/drivers/net/can/xilinx_can.c b/drivers/net/can/xilinx_can.c index abe58f1..c8691a1 100644 --- a/drivers/net/can/xilinx_can.c +++ b/drivers/net/can/xilinx_can.c @@ -31,6 +31,7 @@ #include <linux/phy/phy.h> #include <linux/pm_runtime.h> #include <linux/reset.h> +#include <linux/u64_stats_sync.h> #define DRIVER_NAME "xilinx_can" @@ -58,6 +59,13 @@ enum xcan_reg { */ XCAN_F_BTR_OFFSET = 0x08C, /* Data Phase Bit Timing */ XCAN_TRR_OFFSET = 0x0090, /* TX Buffer Ready Request */ + + /* only on AXI CAN cores */ + XCAN_ECC_CFG_OFFSET = 0xC8, /* ECC Configuration */ + XCAN_TXTLFIFO_ECC_OFFSET = 0xCC, /* TXTL FIFO ECC error counter */ + XCAN_TXOLFIFO_ECC_OFFSET = 0xD0, /* TXOL FIFO ECC error counter */ + XCAN_RXFIFO_ECC_OFFSET = 0xD4, /* RX FIFO ECC error counter */ + XCAN_AFR_EXT_OFFSET = 0x00E0, /* Acceptance Filter */ XCAN_FSR_OFFSET = 0x00E8, /* RX FIFO Status */ XCAN_TXMSG_BASE_OFFSET = 0x0100, /* TX Message Space */ @@ -124,6 +132,18 @@ enum xcan_reg { #define XCAN_IXR_TXFLL_MASK 0x00000004 /* Tx FIFO Full intr */ #define XCAN_IXR_TXOK_MASK 0x00000002 /* TX successful intr */ #define XCAN_IXR_ARBLST_MASK 0x00000001 /* Arbitration lost intr */ +#define XCAN_IXR_E2BERX_MASK BIT(23) /* RX FIFO two bit ECC error */ +#define XCAN_IXR_E1BERX_MASK BIT(22) /* RX FIFO one bit ECC error */ +#define XCAN_IXR_E2BETXOL_MASK BIT(21) /* TXOL FIFO two bit ECC error */ +#define XCAN_IXR_E1BETXOL_MASK BIT(20) /* TXOL FIFO One bit ECC error */ +#define XCAN_IXR_E2BETXTL_MASK BIT(19) /* TXTL FIFO Two bit ECC error */ +#define XCAN_IXR_E1BETXTL_MASK BIT(18) /* TXTL FIFO One bit ECC error */ +#define XCAN_IXR_ECC_MASK (XCAN_IXR_E2BERX_MASK | \ + XCAN_IXR_E1BERX_MASK | \ + XCAN_IXR_E2BETXOL_MASK | \ + XCAN_IXR_E1BETXOL_MASK | \ + XCAN_IXR_E2BETXTL_MASK | \ + XCAN_IXR_E1BETXTL_MASK) #define XCAN_IDR_ID1_MASK 0xFFE00000 /* Standard msg identifier */ #define XCAN_IDR_SRR_MASK 0x00100000 /* Substitute remote TXreq */ #define XCAN_IDR_IDE_MASK 0x00080000 /* Identifier extension */ @@ -137,6 +157,11 @@ enum xcan_reg { #define XCAN_2_FSR_RI_MASK 0x0000003F /* RX Read Index */ #define XCAN_DLCR_EDL_MASK 0x08000000 /* EDL Mask in DLC */ #define XCAN_DLCR_BRS_MASK 0x04000000 /* BRS Mask in DLC */ +#define XCAN_ECC_CFG_REECRX_MASK BIT(2) /* Reset RX FIFO ECC error counters */ +#define XCAN_ECC_CFG_REECTXOL_MASK BIT(1) /* Reset TXOL FIFO ECC error counters */ +#define XCAN_ECC_CFG_REECTXTL_MASK BIT(0) /* Reset TXTL FIFO ECC error counters */ +#define XCAN_ECC_1BIT_CNT_MASK GENMASK(15, 0) /* FIFO ECC 1bit count mask */ +#define XCAN_ECC_2BIT_CNT_MASK GENMASK(31, 16) /* FIFO ECC 2bit count mask */ /* CAN register bit shift - XCAN_<REG>_<BIT>_SHIFT */ #define XCAN_BRPR_TDC_ENABLE BIT(16) /* Transmitter Delay Compensation (TDC) Enable */ @@ -202,6 +227,13 @@ struct xcan_devtype_data { * @devtype: Device type specific constants * @transceiver: Optional pointer to associated CAN transceiver * @rstc: Pointer to reset control + * @ecc_enable: ECC enable flag + * @ecc_2bit_rxfifo_cnt: RXFIFO 2bit ECC count + * @ecc_1bit_rxfifo_cnt: RXFIFO 1bit ECC count + * @ecc_2bit_txolfifo_cnt: TXOLFIFO 2bit ECC count + * @ecc_1bit_txolfifo_cnt: TXOLFIFO 1bit ECC count + * @ecc_2bit_txtlfifo_cnt: TXTLFIFO 2bit ECC count + * @ecc_1bit_txtlfifo_cnt: TXTLFIFO 1bit ECC count */ struct xcan_priv { struct can_priv can; @@ -221,6 +253,13 @@ struct xcan_priv { struct xcan_devtype_data devtype; struct phy *transceiver; struct reset_control *rstc; + bool ecc_enable; + u64_stats_t ecc_2bit_rxfifo_cnt; + u64_stats_t ecc_1bit_rxfifo_cnt; + u64_stats_t ecc_2bit_txolfifo_cnt; + u64_stats_t ecc_1bit_txolfifo_cnt; + u64_stats_t ecc_2bit_txtlfifo_cnt; + u64_stats_t ecc_1bit_txtlfifo_cnt; }; /* CAN Bittiming constants as per Xilinx CAN specs */ @@ -523,6 +562,9 @@ static int xcan_chip_start(struct net_device *ndev) XCAN_IXR_ERROR_MASK | XCAN_IXR_RXOFLW_MASK | XCAN_IXR_ARBLST_MASK | xcan_rx_int_mask(priv); + if (priv->ecc_enable) + ier |= XCAN_IXR_ECC_MASK; + if (priv->devtype.flags & XCAN_FLAG_RXMNF) ier |= XCAN_IXR_RXMNF_MASK; @@ -1127,6 +1169,50 @@ static void xcan_err_interrupt(struct net_device *ndev, u32 isr) priv->can.can_stats.bus_error++; } + if (priv->ecc_enable && isr & XCAN_IXR_ECC_MASK) { + u32 reg_rx_ecc, reg_txol_ecc, reg_txtl_ecc; + + reg_rx_ecc = priv->read_reg(priv, XCAN_RXFIFO_ECC_OFFSET); + reg_txol_ecc = priv->read_reg(priv, XCAN_TXOLFIFO_ECC_OFFSET); + reg_txtl_ecc = priv->read_reg(priv, XCAN_TXTLFIFO_ECC_OFFSET); + + /* The counter reaches its maximum at 0xffff and does not overflow. + * Accept the small race window between reading and resetting ECC counters. + */ + priv->write_reg(priv, XCAN_ECC_CFG_OFFSET, XCAN_ECC_CFG_REECRX_MASK | + XCAN_ECC_CFG_REECTXOL_MASK | XCAN_ECC_CFG_REECTXTL_MASK); + + if (isr & XCAN_IXR_E2BERX_MASK) { + u64_stats_add(&priv->ecc_2bit_rxfifo_cnt, + FIELD_GET(XCAN_ECC_2BIT_CNT_MASK, reg_rx_ecc)); + } + + if (isr & XCAN_IXR_E1BERX_MASK) { + u64_stats_add(&priv->ecc_1bit_rxfifo_cnt, + FIELD_GET(XCAN_ECC_1BIT_CNT_MASK, reg_rx_ecc)); + } + + if (isr & XCAN_IXR_E2BETXOL_MASK) { + u64_stats_add(&priv->ecc_2bit_txolfifo_cnt, + FIELD_GET(XCAN_ECC_2BIT_CNT_MASK, reg_txol_ecc)); + } + + if (isr & XCAN_IXR_E1BETXOL_MASK) { + u64_stats_add(&priv->ecc_1bit_txolfifo_cnt, + FIELD_GET(XCAN_ECC_1BIT_CNT_MASK, reg_txol_ecc)); + } + + if (isr & XCAN_IXR_E2BETXTL_MASK) { + u64_stats_add(&priv->ecc_2bit_txtlfifo_cnt, + FIELD_GET(XCAN_ECC_2BIT_CNT_MASK, reg_txtl_ecc)); + } + + if (isr & XCAN_IXR_E1BETXTL_MASK) { + u64_stats_add(&priv->ecc_1bit_txtlfifo_cnt, + FIELD_GET(XCAN_ECC_1BIT_CNT_MASK, reg_txtl_ecc)); + } + } + if (cf.can_id) { struct can_frame *skb_cf; struct sk_buff *skb = alloc_can_err_skb(ndev, &skb_cf); @@ -1355,7 +1441,7 @@ static irqreturn_t xcan_interrupt(int irq, void *dev_id) struct net_device *ndev = (struct net_device *)dev_id; struct xcan_priv *priv = netdev_priv(ndev); u32 isr, ier; - u32 isr_errors; + u32 isr_errors, mask; u32 rx_int_mask = xcan_rx_int_mask(priv); /* Get the interrupt status from Xilinx CAN */ @@ -1374,10 +1460,15 @@ static irqreturn_t xcan_interrupt(int irq, void *dev_id) if (isr & XCAN_IXR_TXOK_MASK) xcan_tx_interrupt(ndev, isr); + mask = XCAN_IXR_ERROR_MASK | XCAN_IXR_RXOFLW_MASK | + XCAN_IXR_BSOFF_MASK | XCAN_IXR_ARBLST_MASK | + XCAN_IXR_RXMNF_MASK; + + if (priv->ecc_enable) + mask |= XCAN_IXR_ECC_MASK; + /* Check for the type of error interrupt and Processing it */ - isr_errors = isr & (XCAN_IXR_ERROR_MASK | XCAN_IXR_RXOFLW_MASK | - XCAN_IXR_BSOFF_MASK | XCAN_IXR_ARBLST_MASK | - XCAN_IXR_RXMNF_MASK); + isr_errors = isr & mask; if (isr_errors) { priv->write_reg(priv, XCAN_ICR_OFFSET, isr_errors); xcan_err_interrupt(ndev, isr); @@ -1796,6 +1887,7 @@ static int xcan_probe(struct platform_device *pdev) return -ENOMEM; priv = netdev_priv(ndev); + priv->ecc_enable = of_property_read_bool(pdev->dev.of_node, "xlnx,has-ecc"); priv->dev = &pdev->dev; priv->can.bittiming_const = devtype->bittiming_const; priv->can.do_set_mode = xcan_do_set_mode; @@ -1912,6 +2004,11 @@ static int xcan_probe(struct platform_device *pdev) priv->reg_base, ndev->irq, priv->can.clock.freq, hw_tx_max, priv->tx_max); + if (priv->ecc_enable) { + /* Reset FIFO ECC counters */ + priv->write_reg(priv, XCAN_ECC_CFG_OFFSET, XCAN_ECC_CFG_REECRX_MASK | + XCAN_ECC_CFG_REECTXOL_MASK | XCAN_ECC_CFG_REECTXTL_MASK); + } return 0; err_disableclks: -- 2.1.1