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authorShaohua Li <shaohua.li@intel.com>2008-07-23 10:32:31 +0800
committerJesse Barnes <jbarnes@virtuousgeek.org>2008-07-28 14:56:57 -0700
commit149e16372a2066c5474d8a8db9b252afd57eb427 (patch)
tree075a46f0672739fdab18d2f1e5f06080160de8b0 /drivers/pci
parent5fde244d39b88625ac578d83e6625138714de031 (diff)
downloadblackbird-op-linux-149e16372a2066c5474d8a8db9b252afd57eb427.tar.gz
blackbird-op-linux-149e16372a2066c5474d8a8db9b252afd57eb427.zip
PCI: disable ASPM on pre-1.1 PCIe devices
Disable ASPM on pre-1.1 PCIe devices, as many of them don't implement it correctly. Tested-by: Jack Howarth <howarth@bromo.msbb.uc.edu> Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Diffstat (limited to 'drivers/pci')
-rw-r--r--drivers/pci/pcie/aspm.c13
-rw-r--r--drivers/pci/probe.c3
2 files changed, 15 insertions, 1 deletions
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 759c51a4e399..704605298c5e 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -510,6 +510,7 @@ static int pcie_aspm_sanity_check(struct pci_dev *pdev)
{
struct pci_dev *child_dev;
int child_pos;
+ u32 reg32;
/*
* Some functions in a slot might not all be PCIE functions, very
@@ -519,6 +520,18 @@ static int pcie_aspm_sanity_check(struct pci_dev *pdev)
child_pos = pci_find_capability(child_dev, PCI_CAP_ID_EXP);
if (!child_pos)
return -EINVAL;
+
+ /*
+ * Disable ASPM for pre-1.1 PCIe device, we follow MS to use
+ * RBER bit to determine if a function is 1.1 version device
+ */
+ pci_read_config_dword(child_dev, child_pos + PCI_EXP_DEVCAP,
+ &reg32);
+ if (!(reg32 & PCI_EXP_DEVCAP_RBER)) {
+ printk("Pre-1.1 PCIe device detected, "
+ "disable ASPM for %s\n", pci_name(pdev));
+ return -EINVAL;
+ }
}
return 0;
}
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 203630065839..7098dfb07449 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1057,7 +1057,8 @@ int pci_scan_slot(struct pci_bus *bus, int devfn)
}
}
- if (bus->self)
+ /* only one slot has pcie device */
+ if (bus->self && nr)
pcie_aspm_init_link_state(bus->self);
return nr;
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