[PATCH -v2 16/16] PCI: latency timer doesn't apply to PCIe

From: Myron Stowe
Date: Fri Oct 28 2011 - 17:51:53 EST


From: Myron Stowe <mstowe@xxxxxxxxxx>

The latency timer is read-only and hardwired to zero for all PCIe
devices, both Type 0 and Type 1, so don't bother trying to update it
and cluttering the dmesg log with meaningless "setting latency timer
to 64" messages.

Signed-off-by: Myron Stowe <myron.stowe@xxxxxxxxxx>
---

drivers/pci/pci.c | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index a50e643..a20c01a 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -2607,6 +2607,10 @@ void __weak pcibios_set_master(struct pci_dev *dev)
{
u8 lat;

+ /* The latency timer doesn't apply to PCIe (either Type 0 or Type 1) */
+ if (pci_is_pcie(dev))
+ return;
+
pci_read_config_byte(dev, PCI_LATENCY_TIMER, &lat);
if (lat < 16)
lat = (64 <= pcibios_max_latency) ? 64 : pcibios_max_latency;

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