Am Sonntag, den 06.12.2015, 22:03 -0800 schrieb Andrey Smirnov: > >> However when I boot Linux kernel (with 'igb' driver patched to > >> recognize 8086:1531 VID:PID) on that board and run 'eepromARMtool' > >> (Intel provided EEPROM programming tool) I can see it reading various > >> registers correctly > >> > >> My questions are: > >> - Is anyone currently using i.MX6 PCIe driver in 'next' branch? > > > > I didn't try the latest revision, but with v2015.10.0 PCIe on i.MX6 was > > working fine. > > > >> - Has anyone seen similar behavior on this particular controller > >> and discovered the root cause? > >> > > The symptoms you describe do look to me like the firmware on the i210 > > device doesn't get initialized. Unfortunately I don't have any specific > > pointers where to start searching for the root cause. > > > > I kept looking into the issue and noticed one thing that Linux kernel > does differently -- when handling PCI bridges it allocates bridge > window before that PCI bridge's BAR windows in address space as can be > seen below: > > [ 0.831099] imx6q-pcie 1ffc000.pcie: PCI host bridge to bus 0000:00 > [ 0.837480] pci_bus 0000:00: root bus resource [io 0x1000-0x10000] > [ 0.843878] pci_bus 0000:00: root bus resource [mem 0x01000000-0x01efffff] > [ 0.850881] pci_bus 0000:00: root bus resource [bus 00-ff] > [ 0.856913] PCI: bus0: Fast back to back transfers disabled > [ 0.880182] PCI: bus1: Fast back to back transfers disabled > [ 0.885980] pci 0000:00:00.0: BAR 8: assigned [mem 0x01000000-0x01bfffff] > [ 0.892902] pci 0000:00:00.0: BAR 0: assigned [mem 0x01c00000-0x01cfffff] > [ 0.899806] pci 0000:00:00.0: BAR 6: assigned [mem > 0x01d00000-0x01d0ffff pref] > [ 0.907154] pci 0000:00:00.0: BAR 7: assigned [io 0x1000-0x1fff] > [ 0.913387] pci 0000:01:00.0: BAR 0: assigned [mem 0x01000000-0x017fffff] > [ 0.920324] pci 0000:01:00.0: BAR 3: assigned [mem 0x01800000-0x01803fff] > [ 0.927241] pci 0000:01:00.0: BAR 2: assigned [io 0x1000-0x101f] > [ 0.933480] pci 0000:00:00.0: PCI bridge to [bus 01] > [ 0.938553] pci 0000:00:00.0: bridge window [io 0x1000-0x1fff] > [ 0.944772] pci 0000:00:00.0: bridge window [mem 0x01000000-0x01bfffff] > [ 0.951984] pcieport 0000:00:00.0: Signaling PME through PCIe PME interrupt > [ 0.959056] pci 0000:01:00.0: Signaling PME through PCIe PME interrupt > > > When I tried emulating this behavior in Barebox by moving > "setup_device(dev, 2)" from line 384 to be right after > "postscan_setup_bridge(dev)" in "drivers/pci/pci.c" I was able to > communicate with i210. > > I am bit hesitant to make a patch yet, since for the life of me I > cannot explain this behavior, any thoughts on why this can be > happening? > Can you please compile barebox with config PCI_DEBUG set and provide the output of that? Mybe with and without your change applied? Thanks, Lucas -- Pengutronix e.K. | Lucas Stach | Industrial Linux Solutions | http://www.pengutronix.de/ | _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox
