Hi Pali, Thanks for your comments. On Fri, Jun 4, 2021 at 6:55 PM Pali Rohár <pali@xxxxxxxxxx> wrote: > > On Wednesday 02 June 2021 14:43:53 Sergio Paracuellos wrote: > > Hi Pali, > > > > On Wed, Jun 2, 2021 at 2:23 PM Pali Rohár <pali@xxxxxxxxxx> wrote: > > > > > > On Wednesday 02 June 2021 14:16:26 Sergio Paracuellos wrote: > > > > Hi Pali, > > > > > > > > On Mon, May 31, 2021 at 4:19 PM Sergio Paracuellos > > > > <sergio.paracuellos@xxxxxxxxx> wrote: > > > > > > > > > > On Mon, May 31, 2021 at 3:50 PM Pali Rohár <pali@xxxxxxxxxx> wrote: > > > > > > > > > > > > On Monday 31 May 2021 15:39:55 Sergio Paracuellos wrote: > > > > > > > Hi Pali, > > > > > > > > > > > > > > Thanks for your comments. > > > > > > > > > > > > > > On Mon, May 31, 2021 at 3:14 PM Pali Rohár <pali@xxxxxxxxxx> wrote: > > > > > > > > > > > > > > > > On Saturday 15 May 2021 14:40:53 Sergio Paracuellos wrote: > > > > > > > > > This patch adds a driver for the PCIe controller of MT7621 SoC. > > > > > > > > > > > > > > > > > > Signed-off-by: Sergio Paracuellos <sergio.paracuellos@xxxxxxxxx> > > > > > > > > > --- > > > > > > > > > arch/mips/pci/Makefile | 1 + > > > > > > > > > arch/mips/pci/pci-mt7621.c | 624 +++++++++++++++++++++++++++++++++++++ > > > > > > > > > arch/mips/ralink/Kconfig | 9 +- > > > > > > > > > 3 files changed, 633 insertions(+), 1 deletion(-) > > > > > > > > > create mode 100644 arch/mips/pci/pci-mt7621.c > > > > > > > > > > > > > > > > > > diff --git a/arch/mips/pci/Makefile b/arch/mips/pci/Makefile > > > > > > > > > index f3eecc065e5c..178c550739c4 100644 > > > > > > > > > --- a/arch/mips/pci/Makefile > > > > > > > > > +++ b/arch/mips/pci/Makefile > > > > > > > > > @@ -24,6 +24,7 @@ obj-$(CONFIG_PCI_AR2315) += pci-ar2315.o > > > > > > > > > obj-$(CONFIG_SOC_AR71XX) += pci-ar71xx.o > > > > > > > > > obj-$(CONFIG_PCI_AR724X) += pci-ar724x.o > > > > > > > > > obj-$(CONFIG_PCI_XTALK_BRIDGE) += pci-xtalk-bridge.o > > > > > > > > > +obj-$(CONFIG_PCI_MT7621) += pci-mt7621.o > > > > > > > > > # > > > > > > > > > # These are still pretty much in the old state, watch, go blind. > > > > > > > > > # > > > > > > > > > diff --git a/arch/mips/pci/pci-mt7621.c b/arch/mips/pci/pci-mt7621.c > > > > > > > > > new file mode 100644 > > > > > > > > > index 000000000000..fe1945819d25 > > > > > > > > > --- /dev/null > > > > > > > > > +++ b/arch/mips/pci/pci-mt7621.c > > > > > > > > ... > > > > > > > > > +static int mt7621_pcie_enable_ports(struct mt7621_pcie *pcie) > > > > > > > > > +{ > > > > > > > > > + struct device *dev = pcie->dev; > > > > > > > > > + struct mt7621_pcie_port *port; > > > > > > > > > + u8 num_slots_enabled = 0; > > > > > > > > > + u32 slot; > > > > > > > > > + u32 val; > > > > > > > > > + int err; > > > > > > > > > + > > > > > > > > > + /* Setup MEMWIN and IOWIN */ > > > > > > > > > + pcie_write(pcie, 0xffffffff, RALINK_PCI_MEMBASE); > > > > > > > > > + pcie_write(pcie, pcie->io.start, RALINK_PCI_IOBASE); > > > > > > > > > + > > > > > > > > > + list_for_each_entry(port, &pcie->ports, list) { > > > > > > > > > + if (port->enabled) { > > > > > > > > > + err = clk_prepare_enable(port->clk); > > > > > > > > > + if (err) { > > > > > > > > > + dev_err(dev, "enabling clk pcie%d\n", slot); > > > > > > > > > + return err; > > > > > > > > > + } > > > > > > > > > + > > > > > > > > > + mt7621_pcie_enable_port(port); > > > > > > > > > + dev_info(dev, "PCIE%d enabled\n", port->slot); > > > > > > > > > + num_slots_enabled++; > > > > > > > > > + } > > > > > > > > > + } > > > > > > > > > + > > > > > > > > > + for (slot = 0; slot < num_slots_enabled; slot++) { > > > > > > > > > + val = read_config(pcie, slot, PCI_COMMAND); > > > > > > > > > + val |= PCI_COMMAND_MASTER; > > > > > > > > > + write_config(pcie, slot, PCI_COMMAND, val); > > > > > > > > > > > > > > > > Hello! Is this part of code correct? Because it looks strange if PCIe > > > > > > > > controller driver automatically enables PCI bus mastering, prior device > > > > > > > > driver initialize itself. > > > > > > > > > > > > > > > > Moreover kernel has already function pci_set_master() for this purpose > > > > > > > > which is used by device drivers. > > > > > > > > > > > > > > > > So I think this code can confuse some device drivers... > > > > > > > > > > > > > > I agree that we have pci_set_master() to be used in pci device driver > > > > > > > code. Original controller driver set this bit for enabled slots. Since > > > > > > > there is no documentation at all for the PCI in this SoC > > > > > > > > > > > > I see... this is really a big problem to do any driver development... > > > > > > > > > > For sure it is :(. > > > > > > > > > > > > > > > > > > I have > > > > > > > maintained the setting in the driver in a cleaner way. See original > > > > > > > driver code and the setting here [0]. There is no other reason than > > > > > > > that. I am ok with removing this from here and testing with my two > > > > > > > devices that everything is still ok if having this setting in the pci > > > > > > > controller driver is a real problem. > > > > > > > > > > > > You can run lspci -nnvv with and without PCI_COMMAND_MASTER code and > > > > > > then compare outputs. > > > > > > > > > > > > Device drivers for sure enable PCI_COMMAND_MASTER at the time when it is > > > > > > needed, so it is possible that there would be no difference in lspci > > > > > > output. > > > > > > > > > > Thanks. I will take this into account when v2 is submitted after more > > > > > review comments come :). > > > > > > > > I have tested to remove this and check lspci -nnvv output with and > > > > without PCI_COMMAND_MASTER code and, as you pointed out, there is no > > > > difference between them. Also, both boards are working without > > > > regressions at all. So I will remove this code for next version. > > > > > > Perfect! > > > > > > > Thanks, > > > > Sergio Paracuellos > > > > > > > > > > > > > > > > > > [0]: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git/tree/drivers/staging/mt7621-pci/pci-mt7621.c?h=v4.18#n676 > > > > > > > > > > > > > > Best regards, > > > > > > > Sergio Paracuellos > > > > > > > > > > > > > > > > > + /* configure RC FTS number to 250 when it leaves L0s */ > > > > > > > > > + val = read_config(pcie, slot, PCIE_FTS_NUM); > > > > > > > > > + val &= ~PCIE_FTS_NUM_MASK; > > > > > > > > > + val |= PCIE_FTS_NUM_L0(0x50); > > > > > > > > > + write_config(pcie, slot, PCIE_FTS_NUM, val); > > > > > > Could you look also what is doing this code (PCIE_FTS_NUM)? It is marked > > > as MT specific register. But from this code for me it looks like that it > > > just access config space of some device and therefore it could be some > > > standard PCIe register. Just with hardcoded calculated offset. > > So based on your lspci output, there is no PCIe capability register at > address PCIE_FTS_NUM (0x70c), right? It seems strange to trying access > capability register outside of capability list. This setting is also in the original driver code from mediatek SDK. See [0]. Anyway, I have tried to remove this code and test what happens with my two boards and both of them seem to work properly just by deleting this code. > > > > Could you provide output from lspci -nnvv? So other people could look at > > > it and maybe we decode what is this code doing and if it is needed. > > > > # lspci -nnvv > > 00:02.0 PCI bridge [0604]: Device [0e8d:0801] (rev 01) (prog-if 00 > > [Normal decode]) > > Hm... Device address is 02. But in your code is: > > u8 num_slots_enabled = 0; > ... > list_for_each_entry(port, &pcie->ports, list) { > if (port->enabled) { > ... > num_slots_enabled++; > ... > } > } > ... > for (slot = 0; slot < num_slots_enabled; slot++) { > val = read_config(pcie, slot, ...); > ... > write_config(pcie, slot, ...); > } > > Which means that this code writes to config space of wrong device 0 > (instead of 2)! In function write_config() can be seen that second > parameter specify device of BDF address for bus=0 and function=0. Bridge enumeration depends on a virtual bridge register configuration. But at the end devices connected to the bridge are enumerated as 01:00.0, 02:00.0 and 03:00.0. So in this case the phy used is the one for "pcie2" (00:02.0) and the device connected to it is 01:00.0. For example a board using all the virtual bridges will get an output similar to: [ 16.487166] mt7621-pci 1e140000.pcie: host bridge /pcie@1e140000 ranges: [ 16.500627] mt7621-pci 1e140000.pcie: No bus range found for /pcie@1e140000, using [bus 00-ff] [ 16.518212] mt7621-pci 1e140000.pcie: MEM 0x0060000000..0x006fffffff -> 0x0000000000 [ 16.534531] mt7621-pci 1e140000.pcie: IO 0x001e160000..0x001e16ffff -> 0x0000000000 [ 16.786498] mt7621-pci 1e140000.pcie: PCIE0 enabled [ 16.796220] mt7621-pci 1e140000.pcie: PCIE1 enabled [ 16.805943] mt7621-pci 1e140000.pcie: PCIE2 enabled [ 16.815664] mt7621-pci 1e140000.pcie: PCI coherence region base: 0x60000000, mask/settings: 0xf0000002 [ 16.834398] mt7621-pci 1e140000.pcie: PCI host bridge to bus 0000:00 [ 16.847098] pci_bus 0000:00: root bus resource [io 0x1e160000-0x1e16ffff] [ 16.860806] pci_bus 0000:00: root bus resource [mem 0x60000000-0x6fffffff] [ 16.874504] pci_bus 0000:00: root bus resource [bus 00-ff] [ 16.885441] pci_bus 0000:00: root bus resource [mem 0x60000000-0x6fffffff] (bus address [0x00000000-0x0fffffff]) [ 16.905773] pci 0000:00:00.0: [0e8d:0801] type 01 class 0x060400 [ 16.917772] pci 0000:00:00.0: reg 0x10: [mem 0x00000000-0x7fffffff] [ 16.930260] pci 0000:00:00.0: reg 0x14: initial BAR value 0x00000000 invalid [ 16.944304] pci 0000:00:00.0: reg 0x14: [mem size 0x00010000] [ 16.955841] pci 0000:00:00.0: supports D1 [ 16.963837] pci 0000:00:00.0: PME# supported from D0 D1 D3hot [ 16.975747] pci 0000:00:01.0: [0e8d:0801] type 01 class 0x060400 [ 16.987772] pci 0000:00:01.0: reg 0x10: [mem 0x00000000-0x7fffffff] [ 17.000273] pci 0000:00:01.0: reg 0x14: initial BAR value 0x00000000 invalid [ 17.014311] pci 0000:00:01.0: reg 0x14: [mem size 0x00010000] [ 17.025838] pci 0000:00:01.0: supports D1 [ 17.033828] pci 0000:00:01.0: PME# supported from D0 D1 D3hot [ 17.045699] pci 0000:00:02.0: [0e8d:0801] type 01 class 0x060400 [ 17.057726] pci 0000:00:02.0: reg 0x10: [mem 0x00000000-0x7fffffff] [ 17.070218] pci 0000:00:02.0: reg 0x14: initial BAR value 0x00000000 invalid [ 17.084260] pci 0000:00:02.0: reg 0x14: [mem size 0x00010000] [ 17.095788] pci 0000:00:02.0: supports D1 [ 17.103785] pci 0000:00:02.0: PME# supported from D0 D1 D3hot [ 17.116598] pci 0000:00:00.0: bridge configuration invalid ([bus 00-00]), reconfiguring [ 17.132566] pci 0000:00:01.0: bridge configuration invalid ([bus 00-00]), reconfiguring [ 17.148514] pci 0000:00:02.0: bridge configuration invalid ([bus 00-00]), reconfiguring [ 17.164739] pci 0000:01:00.0: [1b21:0611] type 00 class 0x010185 [ 17.176775] pci 0000:01:00.0: reg 0x10: [io 0x0000-0x0007] [ 17.187892] pci 0000:01:00.0: reg 0x14: [io 0x0000-0x0003] [ 17.199009] pci 0000:01:00.0: reg 0x18: [io 0x0000-0x0007] [ 17.210130] pci 0000:01:00.0: reg 0x1c: [io 0x0000-0x0003] [ 17.221246] pci 0000:01:00.0: reg 0x20: [io 0x0000-0x000f] [ 17.232357] pci 0000:01:00.0: reg 0x24: initial BAR value 0x00000000 invalid [ 17.246411] pci 0000:01:00.0: reg 0x24: [mem size 0x00000200] [ 17.258031] pci 0000:01:00.0: 2.000 Gb/s available PCIe bandwidth, limited by 2.5 GT/s PCIe x1 link at 0000:00:00.0 (capable of 4.000 Gb/s with 5.0 GT/s PCIe x1 link) [ 17.317563] pci 0000:00:00.0: PCI bridge to [bus 01-ff] [ 17.328033] pci 0000:00:00.0: bridge window [io 0x0000-0x0fff] [ 17.340179] pci 0000:00:00.0: bridge window [mem 0x60000000-0x600fffff] [ 17.353703] pci 0000:00:00.0: bridge window [mem 0x60000000-0x600fffff pref] [ 17.368097] pci_bus 0000:01: busn_res: [bus 01-ff] end is updated to 01 [ 17.381550] pci 0000:02:00.0: [1b21:0611] type 00 class 0x010185 [ 17.393573] pci 0000:02:00.0: reg 0x10: [io 0x0000-0x0007] [ 17.404694] pci 0000:02:00.0: reg 0x14: [io 0x0000-0x0003] [ 17.415804] pci 0000:02:00.0: reg 0x18: [io 0x0000-0x0007] [ 17.426916] pci 0000:02:00.0: reg 0x1c: [io 0x0000-0x0003] [ 17.438040] pci 0000:02:00.0: reg 0x20: [io 0x0000-0x000f] [ 17.449148] pci 0000:02:00.0: reg 0x24: initial BAR value 0x00000000 invalid [ 17.463193] pci 0000:02:00.0: reg 0x24: [mem size 0x00000200] [ 17.474803] pci 0000:02:00.0: 2.000 Gb/s available PCIe bandwidth, limited by 2.5 GT/s PCIe x1 link at 0000:00:01.0 (capable of 4.000 Gb/s with 5.0 GT/s PCIe x1 link) [ 17.527554] pci 0000:00:01.0: PCI bridge to [bus 02-ff] [ 17.538014] pci 0000:00:01.0: bridge window [io 0x0000-0x0fff] [ 17.550159] pci 0000:00:01.0: bridge window [mem 0x60000000-0x600fffff] [ 17.563682] pci 0000:00:01.0: bridge window [mem 0x60000000-0x600fffff pref] [ 17.578078] pci_bus 0000:02: busn_res: [bus 02-ff] end is updated to 02 [ 17.591529] pci 0000:03:00.0: [1b21:0611] type 00 class 0x010185 [ 17.603545] pci 0000:03:00.0: reg 0x10: [io 0x0000-0x0007] [ 17.614665] pci 0000:03:00.0: reg 0x14: [io 0x0000-0x0003] [ 17.625775] pci 0000:03:00.0: reg 0x18: [io 0x0000-0x0007] [ 17.636887] pci 0000:03:00.0: reg 0x1c: [io 0x0000-0x0003] [ 17.648009] pci 0000:03:00.0: reg 0x20: [io 0x0000-0x000f] [ 17.659119] pci 0000:03:00.0: reg 0x24: initial BAR value 0x00000000 invalid [ 17.673162] pci 0000:03:00.0: reg 0x24: [mem size 0x00000200] [ 17.684777] pci 0000:03:00.0: 2.000 Gb/s available PCIe bandwidth, limited by 2.5 GT/s PCIe x1 link at 0000:00:02.0 (capable of 4.000 Gb/s with 5.0 GT/s PCIe x1 link) [ 17.737561] pci 0000:00:02.0: PCI bridge to [bus 03-ff] [ 17.748022] pci 0000:00:02.0: bridge window [io 0x0000-0x0fff] [ 17.760167] pci 0000:00:02.0: bridge window [mem 0x60000000-0x600fffff] [ 17.773690] pci 0000:00:02.0: bridge window [mem 0x60000000-0x600fffff pref] [ 17.788085] pci_bus 0000:03: busn_res: [bus 03-ff] end is updated to 03 [ 17.801341] pci 0000:00:00.0: BAR 0: no space for [mem size 0x80000000] [ 17.814518] pci 0000:00:00.0: BAR 0: failed to assign [mem size 0x80000000] [ 17.828392] pci 0000:00:01.0: BAR 0: no space for [mem size 0x80000000] [ 17.841571] pci 0000:00:01.0: BAR 0: failed to assign [mem size 0x80000000] [ 17.855443] pci 0000:00:02.0: BAR 0: no space for [mem size 0x80000000] [ 17.868626] pci 0000:00:02.0: BAR 0: failed to assign [mem size 0x80000000] [ 17.882502] pci 0000:00:00.0: BAR 8: assigned [mem 0x60000000-0x600fffff] [ 17.896028] pci 0000:00:00.0: BAR 9: assigned [mem 0x60100000-0x601fffff pref] [ 17.910419] pci 0000:00:01.0: BAR 8: assigned [mem 0x60200000-0x602fffff] [ 17.923951] pci 0000:00:01.0: BAR 9: assigned [mem 0x60300000-0x603fffff pref] [ 17.938353] pci 0000:00:02.0: BAR 8: assigned [mem 0x60400000-0x604fffff] [ 17.951879] pci 0000:00:02.0: BAR 9: assigned [mem 0x60500000-0x605fffff pref] [ 17.966273] pci 0000:00:00.0: BAR 1: assigned [mem 0x60600000-0x6060ffff] [ 17.979809] pci 0000:00:01.0: BAR 1: assigned [mem 0x60610000-0x6061ffff] [ 17.993341] pci 0000:00:02.0: BAR 1: assigned [mem 0x60620000-0x6062ffff] [ 18.006877] pci 0000:00:00.0: BAR 7: assigned [io 0x1e160000-0x1e160fff] [ 18.020408] pci 0000:00:01.0: BAR 7: assigned [io 0x1e161000-0x1e161fff] [ 18.033932] pci 0000:00:02.0: BAR 7: assigned [io 0x1e162000-0x1e162fff] [ 18.047472] pci 0000:01:00.0: BAR 5: assigned [mem 0x60000000-0x600001ff] [ 18.061005] pci 0000:01:00.0: BAR 4: assigned [io 0x1e160000-0x1e16000f] [ 18.074540] pci 0000:01:00.0: BAR 0: assigned [io 0x1e160010-0x1e160017] [ 18.088070] pci 0000:01:00.0: BAR 2: assigned [io 0x1e160018-0x1e16001f] [ 18.101606] pci 0000:01:00.0: BAR 1: assigned [io 0x1e160020-0x1e160023] [ 18.115139] pci 0000:01:00.0: BAR 3: assigned [io 0x1e160024-0x1e160027] [ 18.128676] pci 0000:00:00.0: PCI bridge to [bus 01] [ 18.138577] pci 0000:00:00.0: bridge window [io 0x1e160000-0x1e160fff] [ 18.152100] pci 0000:00:00.0: bridge window [mem 0x60000000-0x600fffff] [ 18.165627] pci 0000:00:00.0: bridge window [mem 0x60100000-0x601fffff pref] [ 18.180030] pci 0000:02:00.0: BAR 5: assigned [mem 0x60200000-0x602001ff] [ 18.193566] pci 0000:02:00.0: BAR 4: assigned [io 0x1e161000-0x1e16100f] [ 18.207110] pci 0000:02:00.0: BAR 0: assigned [io 0x1e161010-0x1e161017] [ 18.220648] pci 0000:02:00.0: BAR 2: assigned [io 0x1e161018-0x1e16101f] [ 18.234183] pci 0000:02:00.0: BAR 1: assigned [io 0x1e161020-0x1e161023] [ 18.247723] pci 0000:02:00.0: BAR 3: assigned [io 0x1e161024-0x1e161027] [ 18.261257] pci 0000:00:01.0: PCI bridge to [bus 02] [ 18.271165] pci 0000:00:01.0: bridge window [io 0x1e161000-0x1e161fff] [ 18.284695] pci 0000:00:01.0: bridge window [mem 0x60200000-0x602fffff] [ 18.298225] pci 0000:00:01.0: bridge window [mem 0x60300000-0x603fffff pref] [ 18.312630] pci 0000:03:00.0: BAR 5: assigned [mem 0x60400000-0x604001ff] [ 18.326166] pci 0000:03:00.0: BAR 4: assigned [io 0x1e162000-0x1e16200f] [ 18.339702] pci 0000:03:00.0: BAR 0: assigned [io 0x1e162010-0x1e162017] [ 18.353237] pci 0000:03:00.0: BAR 2: assigned [io 0x1e162018-0x1e16201f] [ 18.366775] pci 0000:03:00.0: BAR 1: assigned [io 0x1e162020-0x1e162023] [ 18.380311] pci 0000:03:00.0: BAR 3: assigned [io 0x1e162024-0x1e162027] [ 18.393841] pci 0000:00:02.0: PCI bridge to [bus 03] [ 18.403740] pci 0000:00:02.0: bridge window [io 0x1e162000-0x1e162fff] [ 18.417270] pci 0000:00:02.0: bridge window [mem 0x60400000-0x604fffff] [ 18.430801] pci 0000:00:02.0: bridge window [mem 0x60500000-0x605fffff pref] [ 18.445529] ahci 0000:01:00.0: version 3.0 [ 18.445559] pci 0000:00:00.0: enabling device (0000 -> 0003) [ 18.456853] ahci 0000:01:00.0: enabling device (0000 -> 0003) [ 18.468455] ahci 0000:01:00.0: SSS flag set, parallel bus scan disabled [ 18.481700] ahci 0000:01:00.0: AHCI 0001.0200 32 slots 2 ports 6 Gbps 0x3 impl IDE mode [ 18.497662] ahci 0000:01:00.0: flags: 64bit ncq sntf stag led clo pmp pio slum part ccc sxs [ 18.516777] scsi host0: ahci [ 18.523629] scsi host1: ahci [ 18.529829] ata1: SATA max UDMA/133 abar m512@0x60000000 port 0x60000100 irq 22 [ 18.544447] ata2: SATA max UDMA/133 abar m512@0x60000000 port 0x60000180 irq 22 [ 18.559465] pci 0000:00:01.0: enabling device (0000 -> 0003) [ 18.570786] ahci 0000:02:00.0: enabling device (0000 -> 0003) [ 18.582414] ahci 0000:02:00.0: SSS flag set, parallel bus scan disabled [ 18.595665] ahci 0000:02:00.0: AHCI 0001.0200 32 slots 2 ports 6 Gbps 0x3 impl IDE mode [ 18.611614] ahci 0000:02:00.0: flags: 64bit ncq sntf stag led clo pmp pio slum part ccc sxs [ 18.631053] scsi host2: ahci [ 18.637983] scsi host3: ahci [ 18.644138] ata3: SATA max UDMA/133 abar m512@0x60200000 port 0x60200100 irq 23 [ 18.658792] ata4: SATA max UDMA/133 abar m512@0x60200000 port 0x60200180 irq 23 [ 18.673827] pci 0000:00:02.0: enabling device (0000 -> 0003) [ 18.685151] ahci 0000:03:00.0: enabling device (0000 -> 0003) [ 18.696782] ahci 0000:03:00.0: SSS flag set, parallel bus scan disabled [ 18.710025] ahci 0000:03:00.0: AHCI 0001.0200 32 slots 2 ports 6 Gbps 0x3 impl IDE mode [ 18.725972] ahci 0000:03:00.0: flags: 64bit ncq sntf stag led clo pmp pio slum part ccc sxs And you are totally right, the setting is writing in the wrong place. I changed the device tree and the way interrupts are mapped to avoid using a custom 'map_irq' function [1]. Before that commit the pci virtual bridge register was reordering the buses enumeration depending on link status, so there I should also properly rewrite the code in question. I can rewrite the code to read and write config properly using the slot moving the code into 'mt7621_pcie_enable_port' as follows: static void mt7621_pcie_enable_port(struct mt7621_pcie_port *port) { struct mt7621_pcie *pcie = port->pcie; u32 slot = port->slot; u32 offset = MT7621_PCIE_OFFSET + (slot * MT7621_NEXT_PORT); u32 val; /* enable pcie interrupt */ val = pcie_read(pcie, RALINK_PCI_PCIMSK_ADDR); val |= PCIE_PORT_INT_EN(slot); /* map 2G DDR region */ pcie_write(pcie, PCIE_BAR_MAP_MAX | PCIE_BAR_ENABLE, offset + RALINK_PCI_BAR0SETUP_ADDR); /* configure class code and revision ID */ pcie_write(pcie, PCIE_CLASS_CODE | PCIE_REVISION_ID, offset + RALINK_PCI_CLASS); /* configure RC FTS number to 250 when it leaves L0s */ val = read_config(pcie, slot, PCIE_FTS_NUM); val &= ~PCIE_FTS_NUM_MASK; val |= PCIE_FTS_NUM_L0(0x50); write_config(pcie, slot, PCIE_FTS_NUM, val); } static int mt7621_pcie_enable_ports(struct mt7621_pcie *pcie) { struct device *dev = pcie->dev; struct mt7621_pcie_port *port; int err; /* Setup MEMWIN and IOWIN */ pcie_write(pcie, 0xffffffff, RALINK_PCI_MEMBASE); pcie_write(pcie, pcie->io.start, RALINK_PCI_IOBASE); list_for_each_entry(port, &pcie->ports, list) { if (port->enabled) { err = clk_prepare_enable(port->clk); if (err) { dev_err(dev, "enabling clk pcie%d\n", port->slot); return err; } mt7621_pcie_enable_port(port); dev_info(dev, "PCIE%d enabled\n", port->slot); } } return 0; } Or just delete the setting and the read and write config functions since they are not being used in any other place. My two boards work without this setting but I don't know about other boards. What do you think? Best regards, Sergio Paracuellos [0]: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git/tree/drivers/staging/mt7621-pci/pci-mt7621.c?h=v4.18#n663 [1]: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git/commit/drivers/staging/mt7621-pci?h=staging-testing&id=b99cc3a2b6b62cf994acac5cced03298d9908c9b > > > Device tree node: /sys/firmware/devicetree/base/pcie@1e140000/pcie@2,0 > > Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- > > ParErr- Stepping- SERR- FastB2B- DisINTx- > > Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- > > <TAbort- <MAbort- >SERR- <PERR- INTx- > > Latency: 0 > > Interrupt: pin A routed to IRQ 255 > > Region 1: Memory at 60200000 (32-bit, non-prefetchable) [size=64K] > > Bus: primary=00, secondary=01, subordinate=01, sec-latency=0 > > I/O behind bridge: 00000000-00000fff [size=4K] > > Memory behind bridge: 60000000-600fffff [size=1M] > > Prefetchable memory behind bridge: 60100000-601fffff [size=1M] > > Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- > > <TAbort- <MAbort- <SERR- <PERR- > > BridgeCtl: Parity- SERR+ NoISA- VGA- VGA16- MAbort- >Reset- FastB2B- > > PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn- > > Capabilities: [40] Power Management version 3 > > Flags: PMEClk- DSI- D1+ D2- AuxCurrent=375mA > > PME(D0+,D1+,D2-,D3hot+,D3cold-) > > Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME- > > Capabilities: [50] MSI: Enable- Count=1/1 Maskable- 64bit+ > > Address: 0000000000000000 Data: 0000 > > Capabilities: [70] Express (v2) Root Port (Slot-), MSI 00 > > DevCap: MaxPayload 128 bytes, PhantFunc 0 > > ExtTag- RBE+ > > DevCtl: CorrErr- NonFatalErr- FatalErr- UnsupReq- > > RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop- > > MaxPayload 128 bytes, MaxReadReq 128 bytes > > DevSta: CorrErr+ NonFatalErr- FatalErr- UnsupReq- > > AuxPwr- TransPend- > > LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, > > Exit Latency L0s <512ns, L1 <64us > > ClockPM- Surprise- LLActRep+ BwNot- ASPMOptComp- > > LnkCtl: ASPM Disabled; RCB 128 bytes, Disabled- CommClk- > > ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt- > > LnkSta: Speed 2.5GT/s (ok), Width x1 (ok) > > TrErr- Train- SlotClk+ DLActive+ BWMgmt- ABWMgmt- > > RootCap: CRSVisible- > > RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal- > > PMEIntEna- CRSVisible- > > RootSta: PME ReqID 0000, PMEStatus- PMEPending- > > DevCap2: Completion Timeout: Not Supported, > > TimeoutDis+ NROPrPrP- LTR- > > 10BitTagComp- 10BitTagReq- OBFF Not > > Supported, ExtFmt- EETLPPrefix- > > EmergencyPowerReduction Not Supported, > > EmergencyPowerReductionInit- > > FRS- LN System CLS Not Supported, TPHComp- > > ExtTPHComp- ARIFwd- > > AtomicOpsCap: Routing- 32bit- 64bit- 128bitCAS- > > DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis- > > LTR- OBFF Disabled, ARIFwd- > > AtomicOpsCtl: ReqEn- EgressBlck- > > LnkCap2: Supported Link Speeds: 2.5GT/s, Crosslink- > > Retimer- 2Retimers- DRS- > > LnkCtl2: Target Link Speed: 2.5GT/s, EnterCompliance- SpeedDis- > > Transmit Margin: Normal Operating Range, > > EnterModifiedCompliance- ComplianceSOS- > > Compliance De-emphasis: -6dB > > LnkSta2: Current De-emphasis Level: -6dB, > > EqualizationComplete- EqualizationPhase1- > > EqualizationPhase2- EqualizationPhase3- > > LinkEqualizationRequest- > > Retimer- 2Retimers- CrosslinkRes: unsupported > > Capabilities: [100 v1] Advanced Error Reporting > > UESta: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- > > UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol- > > UEMsk: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- > > UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol- > > UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- > > UnxCmplt- RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol- > > CESta: RxErr+ BadTLP- BadDLLP- Rollover- Timeout- > > AdvNonFatalErr- > > CEMsk: RxErr- BadTLP- BadDLLP- Rollover- Timeout- > > AdvNonFatalErr+ > > AERCap: First Error Pointer: 00, ECRCGenCap+ > > ECRCGenEn- ECRCChkCap+ ECRCChkEn- > > MultHdrRecCap- MultHdrRecEn- TLPPfxPres- HdrLogCap- > > HeaderLog: 00000000 00000000 00000000 00000000 > > RootCmd: CERptEn- NFERptEn- FERptEn- > > RootSta: CERcvd- MultCERcvd- UERcvd- MultUERcvd- > > FirstFatal- NonFatalMsg- FatalMsg- IntMsg 0 > > ErrorSrc: ERR_COR: 0000 ERR_FATAL/NONFATAL: 0000 > > Capabilities: [140 v1] Virtual Channel > > Caps: LPEVC=0 RefClk=100ns PATEntryBits=1 > > Arb: Fixed- WRR32- WRR64- WRR128- > > Ctrl: ArbSelect=Fixed > > Status: InProgress- > > VC0: Caps: PATOffset=00 MaxTimeSlots=1 RejSnoopTrans- > > Arb: Fixed- WRR32- WRR64- WRR128- TWRR128- WRR256- > > Ctrl: Enable+ ID=0 ArbSelect=Fixed TC/VC=ff > > Status: NegoPending- InProgress- > > lspci: Unable to load libkmod resources: error -12 > > > > 01:00.0 Network controller [0280]: MEDIATEK Corp. Device [14c3:7612] > > Subsystem: MEDIATEK Corp. Device [14c3:7612] > > Device tree node: > > /sys/firmware/devicetree/base/pcie@1e140000/pcie@2,0/wifi@0,0 > > Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- > > ParErr- Stepping- SERR- FastB2B- DisINTx- > > Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- > > <TAbort- <MAbort- >SERR- <PERR- INTx- > > Latency: 0 > > Interrupt: pin A routed to IRQ 20 > > Region 0: Memory at 60000000 (64-bit, non-prefetchable) [size=1M] > > Expansion ROM at 60100000 [virtual] [disabled] [size=64K] > > Capabilities: [40] Power Management version 3 > > Flags: PMEClk- DSI- D1- D2- AuxCurrent=375mA > > PME(D0+,D1-,D2-,D3hot+,D3cold+) > > Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME- > > Capabilities: [50] MSI: Enable- Count=1/1 Maskable- 64bit+ > > Address: 0000000000000000 Data: 0000 > > Capabilities: [70] Express (v2) Endpoint, MSI 00 > > DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s > > unlimited, L1 unlimited > > ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ > > FLReset- SlotPowerLimit 0.000W > > DevCtl: CorrErr- NonFatalErr- FatalErr- UnsupReq- > > RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop- > > MaxPayload 128 bytes, MaxReadReq 128 bytes > > DevSta: CorrErr- NonFatalErr- FatalErr- UnsupReq- > > AuxPwr+ TransPend- > > LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, > > Exit Latency L0s <2us, L1 unlimited > > ClockPM+ Surprise- LLActRep- BwNot- ASPMOptComp+ > > LnkCtl: ASPM Disabled; RCB 64 bytes, Disabled- CommClk- > > ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt- > > LnkSta: Speed 2.5GT/s (ok), Width x1 (ok) > > TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt- > > DevCap2: Completion Timeout: Range ABCD, TimeoutDis+ > > NROPrPrP- LTR- > > 10BitTagComp- 10BitTagReq- OBFF Not > > Supported, ExtFmt- EETLPPrefix- > > EmergencyPowerReduction Not Supported, > > EmergencyPowerReductionInit- > > FRS- TPHComp- ExtTPHComp- > > AtomicOpsCap: 32bit- 64bit- 128bitCAS- > > DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis- > > LTR- OBFF Disabled, > > AtomicOpsCtl: ReqEn- > > LnkCap2: Supported Link Speeds: 2.5GT/s, Crosslink- > > Retimer- 2Retimers- DRS- > > LnkCtl2: Target Link Speed: 5GT/s, EnterCompliance- SpeedDis- > > Transmit Margin: Normal Operating Range, > > EnterModifiedCompliance- ComplianceSOS- > > Compliance De-emphasis: -6dB > > LnkSta2: Current De-emphasis Level: -3.5dB, > > EqualizationComplete- EqualizationPhase1- > > EqualizationPhase2- EqualizationPhase3- > > LinkEqualizationRequest- > > Retimer- 2Retimers- CrosslinkRes: unsupported > > Capabilities: [100 v2] Advanced Error Reporting > > UESta: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- > > UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol- > > UEMsk: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- > > UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol- > > UESvrt: DLP+ SDES+ TLP- FCP+ CmpltTO- CmpltAbrt- > > UnxCmplt- RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol- > > CESta: RxErr- BadTLP- BadDLLP- Rollover- Timeout- > > AdvNonFatalErr- > > CEMsk: RxErr- BadTLP- BadDLLP- Rollover- Timeout- > > AdvNonFatalErr+ > > AERCap: First Error Pointer: 00, ECRCGenCap+ > > ECRCGenEn- ECRCChkCap+ ECRCChkEn- > > MultHdrRecCap- MultHdrRecEn- TLPPfxPres- HdrLogCap- > > HeaderLog: 00000000 00000000 00000000 00000000 > > Capabilities: [148 v1] Device Serial Number 00-00-00-00-00-00-00-00 > > Capabilities: [158 v1] Latency Tolerance Reporting > > Max snoop latency: 0ns > > Max no snoop latency: 0ns > > Capabilities: [160 v1] L1 PM Substates > > L1SubCap: PCI-PM_L1.2+ PCI-PM_L1.1+ ASPM_L1.2+ > > ASPM_L1.1+ L1_PM_Substates+ > > PortCommonModeRestoreTime=50us PortTPowerOnTime=10us > > L1SubCtl1: PCI-PM_L1.2- PCI-PM_L1.1- ASPM_L1.2- ASPM_L1.1- > > T_CommonMode=0us LTR1.2_Threshold=0ns > > L1SubCtl2: T_PwrOn=10us > > Kernel driver in use: mt76x2e > > > > Best regards, > > Sergio Paracuellos > > > > > > > > > > > > > > + } > > > > > > > > > + > > > > > > > > > + return 0; > > > > > > > > > +}