Re: [PATCH 3/6] pci, thunder: Add PCIe host controller devicetree bindings
From: Arnd Bergmann <hidden>
Date: 2014-09-24 18:34:54
Also in:
linux-arm-kernel, linux-pci, lkml
On Wednesday 24 September 2014 23:34:04 Sunil Kovvuri wrote:
On Wed, Sep 24, 2014 at 9:36 PM, Arnd Bergmann [off-list ref] wrote:quoted
On Wednesday 24 September 2014 17:37:45 Robert Richter wrote:quoted
+ compatible = "cavium,thunder-pcie"; + device_type = "pci"; + msi-parent = <&its>; + bus-range = <0 255>; + #size-cells = <2>; + #address-cells = <3>; + reg = <0x8480 0x00000000 0 0x10000000>; /* Configuration space */ + ranges = <0x03000000 0x8010 0x00000000 0x8010 0x00000000 0x70 0x00000000>, /* mem ranges */ + <0x03000000 0x8300 0x00000000 0x8300 0x00000000 0x80 0x00000000>, + <0x03000000 0x87e0 0x00000000 0x87e0 0x00000000 0x01 0x00000000>; + };If you claim the entire 0-255 bus range, I think you should also specify a domain, otherwise it's not predictable which domain you get. The interrupt-map and interrupt-map-mask properties are required for PCI, otherwise you can't do LSI interrupts.This PCI controller supports only MSIx interrupts which are edge triggered.
Interesting, so it's not PCI compliant then? I assume this will be fixed in the production version of the silicon, right? Having no support for interrupts mean that the majority of PCI device drivers will fail.
quoted
If your hardware can support it, you should also list I/O space and prefetchable memory spaces. Can you explain why you have multiple non-prefetchable ranges?Our hardware is an ECAM based host controller and doesn't support I/O and prefetchable memory spaces. All on-board PCI devices connected to this PCI controller have fixed resources and doesn't have to be allocated/reassigned. Some of these devices are SRIOV based.
I think you need to mark the ones that are nonrelocatable with flag 0x80000000, otherwise the PCI core might decide to reassign them.
Kernel's SRIOV (pci/iov.c) is expecting 'resource->parent' hierarchy to be set, otherwise doesn't enable SRIOV device. So, here multiple non-prefetchable ranges of root bus aid in resource claiming and setting res->parent hierarchy.
I don't understand. Isn't that just a bug in the code that you are working around with the DT. Have you tried fixing the code instead?
We do call "pci_claim_resource" in controller driver code. "[PATCH 1/6] pci, thunder: Add support for Thunder PCIe host controller."
My guess is that you are using the wrong interface here. Isn't the normal request_resource() in the host driver enough? Arnd -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html