| Message ID | 20230522120038.3749026-1-horatiu.vultur@microchip.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 600761245952d7f70280add6ce02894f1528992b |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net] lan966x: Fix unloading/loading of the driver | expand |
On Mon, May 22, 2023 at 02:00:38PM +0200, Horatiu Vultur wrote: > It was noticing that after a while when unloading/loading the driver and > sending traffic through the switch, it would stop working. It would stop > forwarding any traffic and the only way to get out of this was to do a > power cycle of the board. The root cause seems to be that the switch > core is initialized twice. Apparently initializing twice the switch core > disturbs the pointers in the queue systems in the HW, so after a while > it would stop sending the traffic. Ouch. > Unfortunetly, it is not possible to use a reset of the switch here, nit: s/Unfortunetly/Unfortunately/ > because the reset line is connected to multiple devices like MDIO, > SGPIO, FAN, etc. So then all the devices will get reseted when the nit: s/reseted/reset/ > network driver will be loaded. > So the fix is to check if the core is initialized already and if that is > the case don't initialize it again. > > Fixes: db8bcaad5393 ("net: lan966x: add the basic lan966x driver") > Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> ...
Hello: This patch was applied to netdev/net.git (main) by Paolo Abeni <pabeni@redhat.com>: On Mon, 22 May 2023 14:00:38 +0200 you wrote: > It was noticing that after a while when unloading/loading the driver and > sending traffic through the switch, it would stop working. It would stop > forwarding any traffic and the only way to get out of this was to do a > power cycle of the board. The root cause seems to be that the switch > core is initialized twice. Apparently initializing twice the switch core > disturbs the pointers in the queue systems in the HW, so after a while > it would stop sending the traffic. > Unfortunetly, it is not possible to use a reset of the switch here, > because the reset line is connected to multiple devices like MDIO, > SGPIO, FAN, etc. So then all the devices will get reseted when the > network driver will be loaded. > So the fix is to check if the core is initialized already and if that is > the case don't initialize it again. > > [...] Here is the summary with links: - [net] lan966x: Fix unloading/loading of the driver https://git.kernel.org/netdev/net/c/600761245952 You are awesome, thank you!
diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c index 5f01b21acdd1b..f6931dfb3e68e 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c @@ -1039,6 +1039,16 @@ static int lan966x_reset_switch(struct lan966x *lan966x) reset_control_reset(switch_reset); + /* Don't reinitialize the switch core, if it is already initialized. In + * case it is initialized twice, some pointers inside the queue system + * in HW will get corrupted and then after a while the queue system gets + * full and no traffic is passing through the switch. The issue is seen + * when loading and unloading the driver and sending traffic through the + * switch. + */ + if (lan_rd(lan966x, SYS_RESET_CFG) & SYS_RESET_CFG_CORE_ENA) + return 0; + lan_wr(SYS_RESET_CFG_CORE_ENA_SET(0), lan966x, SYS_RESET_CFG); lan_wr(SYS_RAM_INIT_RAM_INIT_SET(1), lan966x, SYS_RAM_INIT); ret = readx_poll_timeout(lan966x_ram_init, lan966x,
It was noticing that after a while when unloading/loading the driver and sending traffic through the switch, it would stop working. It would stop forwarding any traffic and the only way to get out of this was to do a power cycle of the board. The root cause seems to be that the switch core is initialized twice. Apparently initializing twice the switch core disturbs the pointers in the queue systems in the HW, so after a while it would stop sending the traffic. Unfortunetly, it is not possible to use a reset of the switch here, because the reset line is connected to multiple devices like MDIO, SGPIO, FAN, etc. So then all the devices will get reseted when the network driver will be loaded. So the fix is to check if the core is initialized already and if that is the case don't initialize it again. Fixes: db8bcaad5393 ("net: lan966x: add the basic lan966x driver") Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com> --- drivers/net/ethernet/microchip/lan966x/lan966x_main.c | 10 ++++++++++ 1 file changed, 10 insertions(+)