On 01/28/11 19:37, Matias Garcia wrote:
I'm running a vanilla linux 2.6.37 kernel on a Freescale P2020 dual-core
processor, and have the following conundrum: I configure the FPGA which
brings up a PCIe interface to the processor. I scan both PCI buses on
the system (I believe the second bus is behind the Freescale integrated
bridge on the first), and it doesn't show up. I initiate a reset on the
processor, and both U-boot and Linux now see the FPGA PCI device at
0000:01:00.00. I've noticed some of the memory mappings in the PCI
bridge windows are different between the two boot sequences. I've tried
all manner of pci calls (including the pcibios_fixup routines) on the
bridge device (including removing and re-scanning it), and on bus 1,
which is otherwise empty, to no avail. Following are some debug listings
from dmesg; any help/ideas in tracking down the problem (hardware or
software) is greatly appreciated.
#Boot without FPGA configured:
<snip>
Found FSL PCI host bridge at 0x00000008ff70a000. Firmware bus number:
0->255
PCI host bridge /pcie@8ff70a000 ranges:
MEM 0x0000000880000000..0x000000088fffffff -> 0x0000000080000000
IO 0x00000008a0000000..0x00000008a000ffff -> 0x0000000000000000
/pcie@8ff70a000: PCICSRBAR @ 0xfff00000
/pcie@8ff70a000: WARNING: Outbound window cfg leaves gaps in memory map.
Adjusting the memory map could reduce unnecessary bounce buffering.
/pcie@8ff70a000: DMA window size is 0x80000000
MPC85xx RDB board from Freescale Semiconductor
<...>
PCI: Probing PCI hardware
pci 0000:00:00.0: [1957:0070] type 1 class 0x000b20
pci 0000:00:00.0: ignoring class b20 (doesn't match header type 01)
pci 0000:00:00.0: supports D1 D2
pci 0000:00:00.0: PME# supported from D0 D1 D2 D3hot D3cold
pci 0000:00:00.0: PME# disabled
pci 0000:00:00.0: PCI bridge to [bus 01-ff]
pci 0000:00:00.0: bridge window [io 0x0000-0x0000] (disabled)
pci 0000:00:00.0: bridge window [mem 0x00000000-0x000fffff] (disabled)
pci 0000:00:00.0: bridge window [mem 0x00000000-0x000fffff pref] (disabled)
PCI 0000:00 Cannot reserve Legacy IO [io 0xffbed000-0xffbedfff]
pci 0000:00:00.0: PCI bridge to [bus 01-01]
pci 0000:00:00.0: bridge window [io 0xffbed000-0xffbfcfff]
pci 0000:00:00.0: bridge window [mem 0x880000000-0x88fffffff]
pci 0000:00:00.0: bridge window [mem pref disabled]
pci 0000:00:00.0: enabling device (0106 -> 0107)
pci_bus 0000:00: resource 0 [io 0xffbed000-0xffbfcfff]
pci_bus 0000:00: resource 1 [mem 0x880000000-0x88fffffff]
pci_bus 0000:01: resource 0 [io 0xffbed000-0xffbfcfff]
pci_bus 0000:01: resource 1 [mem 0x880000000-0x88fffffff]
#Reset with FPGA configured:
<snip>
Found FSL PCI host bridge at 0x00000008ff70a000. Firmware bus number:
0->255
PCI host bridge /pcie@8ff70a000 ranges:
MEM 0x0000000880000000..0x000000088fffffff -> 0x0000000080000000
IO 0x00000008a0000000..0x00000008a000ffff -> 0x0000000000000000
/pcie@8ff70a000: PCICSRBAR @ 0xfff00000
/pcie@8ff70a000: WARNING: Outbound window cfg leaves gaps in memory map.
Adjusting the memory map could reduce unnecessary bounce buffering.
/pcie@8ff70a000: DMA window size is 0x80000000
MPC85xx RDB board from Freescale Semiconductor
<...>
PCI: Probing PCI hardware
pci 0000:00:00.0: [1957:0070] type 1 class 0x000b20
pci 0000:00:00.0: ignoring class b20 (doesn't match header type 01)
pci 0000:00:00.0: supports D1 D2
pci 0000:00:00.0: PME# supported from D0 D1 D2 D3hot D3cold
pci 0000:00:00.0: PME# disabled
pci 0000:01:00.0: [1172:0004] type 0 class 0x001000
pci 0000:01:00.0: reg 10: [mem 0x80000000-0x80ffffff]
pci 0000:01:00.0: reg 14: [mem 0x81000000-0x81ffffff]
pci 0000:01:00.0: reg 18: [mem 0x82000000-0x82ffffff]
pci 0000:00:00.0: PCI bridge to [bus 01-ff]
pci 0000:00:00.0: bridge window [io 0x0000-0x0000] (disabled)
pci 0000:00:00.0: bridge window [mem 0x80000000-0x82ffffff]
pci 0000:00:00.0: bridge window [mem 0x10000000-0x000fffff pref] (disabled)
irq: irq 0 on host /soc@8ff700000/pic@40000 mapped to virtual irq 16
PCI 0000:00 Cannot reserve Legacy IO [io 0xffbed000-0xffbedfff]
pci 0000:00:00.0: PCI bridge to [bus 01-01]
pci 0000:00:00.0: bridge window [io 0xffbed000-0xffbfcfff]
pci 0000:00:00.0: bridge window [mem 0x880000000-0x88fffffff]
pci 0000:00:00.0: bridge window [mem pref disabled]
pci 0000:00:00.0: enabling device (0106 -> 0107)
pci_bus 0000:00: resource 0 [io 0xffbed000-0xffbfcfff]
pci_bus 0000:00: resource 1 [mem 0x880000000-0x88fffffff]
pci_bus 0000:01: resource 0 [io 0xffbed000-0xffbfcfff]
pci_bus 0000:01: resource 1 [mem 0x880000000-0x88fffffff]
Hi Mattias,
I'm doing the same on a similar setup, also a P2020 but a 2.6.36 and
with me it works just fine. However I encountered one problem. I
understand it as follows, if there is no physical PCIe link then
somewhere a flag PPC_INDIRECT_TYPE_NO_PCIE_LINK gets set. This has as
result that reading the PCIe config space will fail with a
PCIBIOS_DEVICE_NOT_FOUND (ref
http://lxr.linux.no/#linux+v2.6.37/arch/powerpc/sysdev/indirect_pci.c#L24 )
At
http://lxr.linux.no/#linux+v2.6.37/arch/powerpc/include/asm/pci-bridge.h#L105
they specify this as a workaround since the PCIe might hang if there is
no physical link. So my workaround for this issue was:
- load the fpga
- travel down the pci bus to the correct bus where the fpga is attached
use a pci_bus_to_host() to obtain a struct pci_controller, unset the
PPC_INDIRECT_TYPE_NO_PCIE_LINK and call a pci_rescon_bus() on that bus.
After doing this I can find access the FPGA, and reload it if needed.
Not a clue if this is 'the proper way' to do it, but it works for me.
gr
E.
--
Elie De Brauwer
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