于 2013-01-23 17:21, Andrew Murray 写道: > On Wed, Jan 23, 2013 at 08:01:36AM +0000, Yijing Wang wrote: >> 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. Document these into >> kernel-parameters.txt help users to understand and use the parameters. >> >> 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..4dfa8d2 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 [X86] Disable PCI-E MPS turning and using >> + the BIOS configured MPS defaults. >> + pcie_bus_safe [X86] Use the smallest common denominator MPS >> + of the entire tree below a root complex for every device >> + on that fabric. Can avoid inconsistent mps problem caused >> + by hotplug. >> + pcie_bus_perf [X86] Configure pcie device MPS to the largest >> + allowable MPS based on its parent bus.Improve performance >> + as much as possible. >> + pcie_bus_peer2peer [X86] Make the system wide MPS the smallest >> + possible value (128B).This configuration could prevent it >> + from working by having the MPS on one root port different >> + than the MPS on another. >> 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. >> > I was searching for documentation on this the other day. > > It's not just X86 that use these options, PowerPC and Tile also use them (grep > for users of pcie_bus_configure_settings). I've also noticed a call to it from > hotplug as well... Hi Andrew, Thanks for reminder! I will update this patch right now. > > In addition these options also have an effect on MRRS - I've not figured out > what effect they have, but you can look in drivers/pci/probe.c at the > pcie_write_mrrs function. This is a separate issue, Andrew, can you provide the effetct problem log or detail information? That will helps us to analyze this issue. > > Andrew Murray > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
