Hi Russel king, > -----Original Message----- > From: Russell King <linux@xxxxxxxxxxxxxxx> > Sent: 03 March 2025 11:19 > Subject: Re: [PATCH 3/3] net: stmmac: Add DWMAC glue layer for Renesas GBETH > > 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 > 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. FYI, With linux next, On RZ/G3E SoC which has similar IP as RZ/V2H, ethernet works during suspend entry/exit Even though STR is not fully functional yet. I have integrated KEY_SLEEP button on RZ/G3E. On pressing the button, I can see the ethernet link goes down during suspend entry and link up happens during suspend exit. I will test your suspend/resume patch soon with net-next. Cheers, Biju
