This is a note to let you know that I've just added the patch titled can: kvaser_pciefd: Do not send EFLUSH command on TFD interrupt to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: can-kvaser_pciefd-do-not-send-eflush-command-on-tfd-interrupt.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 262d7a52ba27525e3c1203230c9f0524e48bbb34 Mon Sep 17 00:00:00 2001 From: Jimmy Assarsson <extja@xxxxxxxxxx> Date: Tue, 16 May 2023 15:43:17 +0200 Subject: can: kvaser_pciefd: Do not send EFLUSH command on TFD interrupt From: Jimmy Assarsson <extja@xxxxxxxxxx> commit 262d7a52ba27525e3c1203230c9f0524e48bbb34 upstream. Under certain circumstances we send two EFLUSH commands, resulting in two EFLUSH ack packets, while only expecting a single EFLUSH ack. This can cause the driver Tx flush completion to get out of sync. To avoid this problem, don't enable the "Transmit buffer flush done" (TFD) interrupt and remove the code handling it. Now we only send EFLUSH command after receiving status packet with "Init detected" (IDET) bit set. Fixes: 26ad340e582d ("can: kvaser_pciefd: Add driver for Kvaser PCIEcan devices") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Jimmy Assarsson <extja@xxxxxxxxxx> Link: https://lore.kernel.org/r/20230516134318.104279-6-extja@xxxxxxxxxx Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/can/kvaser_pciefd.c | 21 ++++----------------- 1 file changed, 4 insertions(+), 17 deletions(-) --- a/drivers/net/can/kvaser_pciefd.c +++ b/drivers/net/can/kvaser_pciefd.c @@ -533,7 +533,7 @@ static int kvaser_pciefd_set_tx_irq(stru KVASER_PCIEFD_KCAN_IRQ_TOF | KVASER_PCIEFD_KCAN_IRQ_ABD | KVASER_PCIEFD_KCAN_IRQ_TAE | KVASER_PCIEFD_KCAN_IRQ_TAL | KVASER_PCIEFD_KCAN_IRQ_FDIC | KVASER_PCIEFD_KCAN_IRQ_BPP | - KVASER_PCIEFD_KCAN_IRQ_TAR | KVASER_PCIEFD_KCAN_IRQ_TFD; + KVASER_PCIEFD_KCAN_IRQ_TAR; iowrite32(msk, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG); @@ -581,7 +581,7 @@ static void kvaser_pciefd_start_controll spin_lock_irqsave(&can->lock, irq); iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG); - iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD | KVASER_PCIEFD_KCAN_IRQ_TFD, + iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG); status = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_STAT_REG); @@ -624,7 +624,7 @@ static int kvaser_pciefd_bus_on(struct k iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG); iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG); - iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD | KVASER_PCIEFD_KCAN_IRQ_TFD, + iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG); mode = ioread32(can->reg_base + KVASER_PCIEFD_KCAN_MODE_REG); @@ -1011,8 +1011,7 @@ static int kvaser_pciefd_setup_can_ctrls SET_NETDEV_DEV(netdev, &pcie->pci->dev); iowrite32(-1, can->reg_base + KVASER_PCIEFD_KCAN_IRQ_REG); - iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD | - KVASER_PCIEFD_KCAN_IRQ_TFD, + iowrite32(KVASER_PCIEFD_KCAN_IRQ_ABD, can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG); pcie->can[i] = can; @@ -1441,9 +1440,6 @@ static int kvaser_pciefd_handle_status_p cmd = KVASER_PCIEFD_KCAN_CMD_AT; cmd |= ++can->cmd_seq << KVASER_PCIEFD_KCAN_CMD_SEQ_SHIFT; iowrite32(cmd, can->reg_base + KVASER_PCIEFD_KCAN_CMD_REG); - - iowrite32(KVASER_PCIEFD_KCAN_IRQ_TFD, - can->reg_base + KVASER_PCIEFD_KCAN_IEN_REG); } else if (p->header[0] & KVASER_PCIEFD_SPACK_IDET && p->header[0] & KVASER_PCIEFD_SPACK_IRM && cmdseq == (p->header[1] & KVASER_PCIEFD_PACKET_SEQ_MSK) && @@ -1732,15 +1728,6 @@ static int kvaser_pciefd_transmit_irq(st if (irq & KVASER_PCIEFD_KCAN_IRQ_TOF) netdev_err(can->can.dev, "Tx FIFO overflow\n"); - if (irq & KVASER_PCIEFD_KCAN_IRQ_TFD) { - u8 count = ioread32(can->reg_base + - KVASER_PCIEFD_KCAN_TX_NPACKETS_REG) & 0xff; - - if (count == 0) - iowrite32(KVASER_PCIEFD_KCAN_CTRL_EFLUSH, - can->reg_base + KVASER_PCIEFD_KCAN_CTRL_REG); - } - if (irq & KVASER_PCIEFD_KCAN_IRQ_BPP) netdev_err(can->can.dev, "Fail to change bittiming, when not in reset mode\n"); Patches currently in stable-queue which might be from extja@xxxxxxxxxx are queue-5.10/can-kvaser_pciefd-call-request_irq-before-enabling-interrupts.patch queue-5.10/can-kvaser_pciefd-set-can_state_stopped-in-kvaser_pciefd_stop.patch queue-5.10/can-kvaser_pciefd-clear-listen-only-bit-if-not-explicitly-requested.patch queue-5.10/can-kvaser_pciefd-empty-srb-buffer-in-probe.patch queue-5.10/can-kvaser_pciefd-disable-interrupts-in-probe-error-path.patch queue-5.10/can-kvaser_pciefd-do-not-send-eflush-command-on-tfd-interrupt.patch