diff options
Diffstat (limited to 'drivers/net/tg3.c')
| -rw-r--r-- | drivers/net/tg3.c | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c index 4eef798fbb7b..6af8ebcf35f0 100644 --- a/drivers/net/tg3.c +++ b/drivers/net/tg3.c @@ -6690,13 +6690,29 @@ static void tg3_timer(unsigned long __opaque) tp->timer_counter = tp->timer_multiplier; } - /* Heartbeat is only sent once every 2 seconds. */ + /* Heartbeat is only sent once every 2 seconds. + * + * The heartbeat is to tell the ASF firmware that the host + * driver is still alive. In the event that the OS crashes, + * ASF needs to reset the hardware to free up the FIFO space + * that may be filled with rx packets destined for the host. + * If the FIFO is full, ASF will no longer function properly. + * + * Unintended resets have been reported on real time kernels + * where the timer doesn't run on time. Netpoll will also have + * same problem. + * + * The new FWCMD_NICDRV_ALIVE3 command tells the ASF firmware + * to check the ring condition when the heartbeat is expiring + * before doing the reset. This will prevent most unintended + * resets. + */ if (!--tp->asf_counter) { if (tp->tg3_flags & TG3_FLAG_ENABLE_ASF) { u32 val; tg3_write_mem(tp, NIC_SRAM_FW_CMD_MBOX, - FWCMD_NICDRV_ALIVE2); + FWCMD_NICDRV_ALIVE3); tg3_write_mem(tp, NIC_SRAM_FW_CMD_LEN_MBOX, 4); /* 5 seconds timeout */ tg3_write_mem(tp, NIC_SRAM_FW_CMD_DATA_MBOX, 5); |