On Fri, Jan 25, 2013 at 2:36 AM, Yijing Wang <wangyijing@xxxxxxxxxx> wrote: > v0->v1: Update MPS parameters as non-arch and add MRRS > description into pcie_bus_perf parameter suggested > by Andrew Murray. > v1->v2: Update some semantic problems and add MPS and MRRS > explanation suggested by Joe Lawrence and Randy Dunlap. > v2->v3: Update some semantic problems and the description > of pcie_bus_safe and pcie_bus_peer2peer suggested > by Bjorn Helgaas. > > Document PCIE BUS MPS parameters pcie_bus_tune_off, pcie_bus_safe, > pcie_bus_peer2peer, pcie_bus_perf into Documentation/kernel-parameters.txt. > These parameters were introduced by Jon Mason <mason@xxxxxxxx> at > commit 5f39e6705 and commit b03e7495a8. > > Signed-off-by: Yijing Wang <wangyijing@xxxxxxxxxx> > --- > Documentation/kernel-parameters.txt | 13 +++++++++++++ > 1 files changed, 13 insertions(+), 0 deletions(-) > > diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt > index 363e348..2997df2 100644 > --- a/Documentation/kernel-parameters.txt > +++ b/Documentation/kernel-parameters.txt > @@ -2227,6 +2227,19 @@ bytes respectively. Such letter suffixes can also be entirely omitted. > This sorting is done to get a device > order compatible with older (<= 2.4) kernels. > nobfsort Don't sort PCI devices into breadth-first order. > + pcie_bus_tune_off Disable PCIe MPS (Max Payload Size) > + tuning and use the BIOS-configured MPS defaults. > + pcie_bus_safe Use the smallest supported MPS of any device > + below a root complex. This isn't correct. It should be something like "The largest MPS common to all devices below the root complex". > + pcie_bus_perf Configure device MPS to the largest > + allowable MPS based on its parent bus. Also set > + MRRS (Max Read Request Size) to the largest supported > + value (no larger than the MPS that the device or bus > + can support) for best performance. > + pcie_bus_peer2peer Set every device's MPS to 128B, which > + every device is guaranteed to support. This > + configuration allows peer-to-peer DMA between any pair > + of devices possibly at the cost of reduced performance. > cbiosize=nn[KMG] The fixed amount of bus space which is > reserved for the CardBus bridge's IO window. > The default value is 256 bytes. > -- > 1.7.1 > > -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
