[PATCH] ARM: pci: add call to pcie_bus_configure_settings()
m-karicheri2 at ti.com
Wed May 28 10:14:04 PDT 2014
On 5/28/2014 12:58 PM, Jason Gunthorpe wrote:
> On Wed, May 28, 2014 at 10:26:16AM -0400, Murali Karicheri wrote:
>> PCI core supports PCIE_BUS_SAFE and PCIE_BUS_PERFORMANCE modes.
>> PCI controllers may not be able to handle pay load size higher
>> than MPS and also read data size higher than MRSS. So limit the
>> max to the least common supported payload size by calling
>> pcie_bus_configure_settings(). Using pci=pcie_bus_safe do a walk
>> and set the MPS to least common value used by devices on the bus.
>> pci=pcie_bus_perf does do a walk and set MRSS to MPS.
> This text doesn't make much sense.. Calling
> pcie_bus_configure_settings is just a good thing to do, the fact it
> helps avoid a HW defect in a specific PCI-E implementation is not the
> main reason to add this to the core ARM code.
> Call pcie_bus_configure_settings on ARM, like for other
> platforms. pcie_bus_configure_settings makes sure the MPS across the
> bus is uniform and provides the ability to tune the MRSS and MPS to
> higher performance values.
> This is particularly important for embedded where there is no
> firmware to program these PCI-E settings for the OS.
Thanks. I will add this text for v1.
>> + list_for_each_entry(child, &bus->children, node)
>> + pcie_bus_configure_settings(child);
> Missing indent.
Will fix in v1.
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