Commit 149e1637 authored by Shaohua Li's avatar Shaohua Li Committed by Jesse Barnes

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: default avatarJack Howarth <howarth@bromo.msbb.uc.edu>
Signed-off-by: default avatarShaohua Li <shaohua.li@intel.com>
Signed-off-by: default avatarJesse Barnes <jbarnes@virtuousgeek.org>
parent 5fde244d
......@@ -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;
}
......
......@@ -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;
......
......@@ -374,6 +374,7 @@
#define PCI_EXP_DEVCAP_ATN_BUT 0x1000 /* Attention Button Present */
#define PCI_EXP_DEVCAP_ATN_IND 0x2000 /* Attention Indicator Present */
#define PCI_EXP_DEVCAP_PWR_IND 0x4000 /* Power Indicator Present */
#define PCI_EXP_DEVCAP_RBER 0x8000 /* Role-Based Error Reporting */
#define PCI_EXP_DEVCAP_PWR_VAL 0x3fc0000 /* Slot Power Limit Value */
#define PCI_EXP_DEVCAP_PWR_SCL 0xc000000 /* Slot Power Limit Scale */
#define PCI_EXP_DEVCTL 8 /* Device Control */
......
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