On Sun, Mar 02, 2025 at 10:02:15PM +0000, Lad, Prabhakar wrote: > Hi Russell, > > On Sun, Mar 2, 2025 at 9:44 PM Russell King (Oracle) > <linux@xxxxxxxxxxxxxxx> wrote: > > > > On Sun, Mar 02, 2025 at 09:20:49PM +0000, Lad, Prabhakar wrote: > > > Hi Russell, > > > > What is the reason for setting this flag? If it's because of suspend/ > > > > resume failures, does my "net: stmmac: fix resume failures due to > > > > RX clock" series solve this for you without requiring this flag? > > > > > > > Ive set this flag based on the configuration supported by this IP. > > > Unfortunately the platform which I am working on doesn't support s2r > > > yet so I cannot test suspend/resume path yet. But I do see an issue > > > when I unload and load just the glue module the DMA reset fails. > > > > Thanks for that feedback - that's a scenario I hadn't considered. > > > > I was trying to avoid having to disable LPI RX clock-stop on suspend by > > ensuring that it was enabled at resume time. I think that's valid, but > > you've brought up another similar scenario: > > > > - device is brought up, configures RX clock stop > > - links with media, negotiates EEE > > - driver is unloaded, link doesn't go down, but due to no traffic goes > > into idle, so RX clock is stopped > > - driver reloaded, RX clock still stopped, reset fails > > > > I would like to solve that so we can get the power savings from > > stopping the clock, but still have reset work when necessary. > > > I would be happy to test the patches ;) > > > I'm guessing that the "DMA reset fails" refers to this path: > > > > stmmac_open() -> __stmmac_open() -> stmmac_hw_setup() -> > > stmmac_init_dma_engine() -> stmmac_reset() ? > > > Yes. > > > In other words, when the device is being brought back up > > adminsitratively? > > > > What happens if you (replace $if): > > > > # ip li set dev $if down > > # ip li set dev $if up > > > > Does that also fail without STMMAC_FLAG_RX_CLK_RUNS_IN_LPI set? > > > Logs without STMMAC_FLAG_RX_CLK_RUNS_IN_LPI flag set: > -------------------------------------------------------------- > root@rzv2h-evk-alpha:~# ip li set dev eth1 down > [ 33.606549] renesas-gbeth 15c40000.ethernet eth1: Link is Down > root@rzv2h-evk-alpha:~# > root@rzv2h-evk-alpha:~# ip li set dev eth0 down > [ 37.356992] renesas-gbeth 15c30000.ethernet eth0: Link is Down > root@rzv2h-evk-alpha:~# > root@rzv2h-evk-alpha:~# ip li set dev eth1 up > [ 43.974803] renesas-gbeth 15c40000.ethernet eth1: Register > MEM_TYPE_PAGE_POOL RxQ-0 > [ 43.983189] renesas-gbeth 15c40000.ethernet eth1: Register > MEM_TYPE_PAGE_POOL RxQ-1 > [ 43.991155] renesas-gbeth 15c40000.ethernet eth1: Register > MEM_TYPE_PAGE_POOL RxQ-2 > [ 43.999128] renesas-gbeth 15c40000.ethernet eth1: Register > MEM_TYPE_PAGE_POOL RxQ-3 > [ 44.072079] renesas-gbeth 15c40000.ethernet eth1: PHY [stmmac-1:00] > driver [Microchip KSZ9131 Gigabit PHY] (irq=POLL) > [ 44.094605] dwmac4: Master AXI performs fixed burst length > [ 44.100138] renesas-gbeth 15c40000.ethernet eth1: No Safety > Features support found > [ 44.107748] renesas-gbeth 15c40000.ethernet eth1: IEEE 1588-2008 > Advanced Timestamp supported > [ 44.116725] renesas-gbeth 15c40000.ethernet eth1: registered PTP clock > [ 44.123352] renesas-gbeth 15c40000.ethernet eth1: configuring for > phy/rgmii-id link mode > root@rzv2h-evk-alpha:~# > root@rzv2h-evk-alpha:~# ip li set dev eth1[ 47.207761] renesas-gbeth > 15c40000.ethernet eth1: Link is Up - 1Gbps/Full - flow control off > ^C > root@rzv2h-evk-alpha:~# ^C > root@rzv2h-evk-alpha:~# ip li set dev eth0 up > [ 55.636722] renesas-gbeth 15c30000.ethernet eth0: Register > MEM_TYPE_PAGE_POOL RxQ-0 > [ 55.645139] renesas-gbeth 15c30000.ethernet eth0: Register > MEM_TYPE_PAGE_POOL RxQ-1 > [ 55.653111] renesas-gbeth 15c30000.ethernet eth0: Register > MEM_TYPE_PAGE_POOL RxQ-2 > [ 55.661073] renesas-gbeth 15c30000.ethernet eth0: Register > MEM_TYPE_PAGE_POOL RxQ-3 > [ 55.732087] renesas-gbeth 15c30000.ethernet eth0: PHY [stmmac-0:00] > driver [Microchip KSZ9131 Gigabit PHY] (irq=POLL) > [ 55.754612] dwmac4: Master AXI performs fixed burst length > [ 55.760143] renesas-gbeth 15c30000.ethernet eth0: No Safety > Features support found > [ 55.767740] renesas-gbeth 15c30000.ethernet eth0: IEEE 1588-2008 > Advanced Timestamp supported > [ 55.776705] renesas-gbeth 15c30000.ethernet eth0: registered PTP clock > [ 55.783333] renesas-gbeth 15c30000.ethernet eth0: configuring for > phy/rgmii-id link mode > root@rzv2h-evk-alpha:~# > root@rzv2h-evk-alpha:~# [ 58.855844] renesas-gbeth 15c30000.ethernet > eth0: tx_clk_stop=1 > [ 58.861989] renesas-gbeth 15c30000.ethernet eth0: Link is Up - > 1Gbps/Full - flow control rx/tx > > root@rzv2h-evk-alpha:~# > root@rzv2h-evk-alpha:~# > > Logs with STMMAC_FLAG_RX_CLK_RUNS_IN_LPI flag set: > -------------------------------------------------------------- > root@rzv2h-evk-alpha:~# ip li set dev eth1 down > [ 30.053790] renesas-gbeth 15c40000.ethernet eth1: Link is Down > root@rzv2h-evk-alpha:~# ip li set dev eth0 down > [ 35.366935] renesas-gbeth 15c30000.ethernet eth0: Link is Down > root@rzv2h-evk-alpha:~# ip li set dev eth1 up > [ 40.448563] renesas-gbeth 15c40000.ethernet eth1: Register > MEM_TYPE_PAGE_POOL RxQ-0 > [ 40.456725] renesas-gbeth 15c40000.ethernet eth1: Register > MEM_TYPE_PAGE_POOL RxQ-1 > [ 40.464893] renesas-gbeth 15c40000.ethernet eth1: Register > MEM_TYPE_PAGE_POOL RxQ-2 > [ 40.472840] renesas-gbeth 15c40000.ethernet eth1: Register > MEM_TYPE_PAGE_POOL RxQ-3 > [ 40.543895] renesas-gbeth 15c40000.ethernet eth1: PHY [stmmac-1:00] > driver [Microchip KSZ9131 Gigabit PHY] (irq=POLL) > [ 40.566419] dwmac4: Master AXI performs fixed burst length > [ 40.571949] renesas-gbeth 15c40000.ethernet eth1: No Safety > Features support found > [ 40.579550] renesas-gbeth 15c40000.ethernet eth1: IEEE 1588-2008 > Advanced Timestamp supported > [ 40.588505] renesas-gbeth 15c40000.ethernet eth1: registered PTP clock > [ 40.595135] renesas-gbeth 15c40000.ethernet eth1: configuring for > phy/rgmii-id link mode > root@rzv2h-evk-alpha:~# > root@rzv2h-evk-alpha:~# [ 43.687551] renesas-gbeth 15c40000.ethernet > eth1: Link is Up - 1Gbps/Full - flow control off > > root@rzv2h-evk-alpha:~# ip li set dev eth0 up > [ 49.644479] renesas-gbeth 15c30000.ethernet eth0: Register > MEM_TYPE_PAGE_POOL RxQ-0 > [ 49.652719] renesas-gbeth 15c30000.ethernet eth0: Register > MEM_TYPE_PAGE_POOL RxQ-1 > [ 49.660681] renesas-gbeth 15c30000.ethernet eth0: Register > MEM_TYPE_PAGE_POOL RxQ-2 > [ 49.669059] renesas-gbeth 15c30000.ethernet eth0: Register > MEM_TYPE_PAGE_POOL RxQ-3 > [ 49.740011] renesas-gbeth 15c30000.ethernet eth0: PHY [stmmac-0:00] > driver [Microchip KSZ9131 Gigabit PHY] (irq=POLL) > [ 49.762518] dwmac4: Master AXI performs fixed burst length > [ 49.768057] renesas-gbeth 15c30000.ethernet eth0: No Safety > Features support found > [ 49.775655] renesas-gbeth 15c30000.ethernet eth0: IEEE 1588-2008 > Advanced Timestamp supported > [ 49.784609] renesas-gbeth 15c30000.ethernet eth0: registered PTP clock > [ 49.791236] renesas-gbeth 15c30000.ethernet eth0: configuring for > phy/rgmii-id link mode > root@rzv2h-evk-alpha:~# > root@rzv2h-evk-alpha:~# [ 52.871635] renesas-gbeth 15c30000.ethernet > eth0: tx_clk_stop=1 > [ 52.877777] renesas-gbeth 15c30000.ethernet eth0: Link is Up - > 1Gbps/Full - flow control rx/tx I would like to get to the bottom of why this fails for module removal/ insertion, but not for admistratively down/upping the interface. Removal of your module will unregister the netdev, and part of that work will bring the netdev administratively down. When re-inserting the module, that will trigger various userspace events, and it will be userspace bringing the network interface(s) back up. This should be no different from administratively down/upping the interface but it seems you get different behaviour. I'd like to understand why that is, because at the moment I'm wondering whether my patches that address the suspend/resume need further work before I send them - but in order to assess that, I need to work out why your issue only seems to occur in the module removal/insertion and not down/up as well as I'd expect. Please could you investigate this? Thanks. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!
