lkml.org 
[lkml]   [2013]   [Jan]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v4] PCI: Document PCIE BUS MPS parameters
Date
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.
v3->v4: Update pcie_bus_safe description suggested by Jon Mason

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 <jdmason@kudzu.us> at
commit 5f39e6705 and commit b03e7495a8.

Signed-off-by: Yijing Wang <wangyijing@huawei.com>
---
Documentation/kernel-parameters.txt | 14 ++++++++++++++
1 files changed, 14 insertions(+), 0 deletions(-)

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 363e348..6ad9b95 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -2227,6 +2227,20 @@ 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 Set every device's MPS to the largest MPSS
+ (Max Payload Size Support) 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



\
 
 \ /
  Last update: 2013-01-30 03:41    [W:0.037 / U:1.552 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site