| From cebbert@redhat.com Thu Oct 16 16:08:16 2008 |
| From: Shaohua Li <shaohua.li@intel.com> |
| Date: Mon, 13 Oct 2008 19:39:25 -0400 |
| Subject: PCI: disable ASPM on pre-1.1 PCIe devices |
| To: stable@kernel.org |
| Cc: Jesse Barnes <jbarnes@virtuousgeek.org> |
| Message-ID: <20081013193925.477fc770@redhat.com> |
| |
| From: Shaohua Li <shaohua.li@intel.com> |
| |
| commit 149e16372a2066c5474d8a8db9b252afd57eb427 upstream |
| |
| 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> |
| Cc: Chuck Ebbert <cebbert@redhat.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
| |
| --- |
| drivers/pci/pcie/aspm.c | 13 +++++++++++++ |
| drivers/pci/probe.c | 3 ++- |
| include/linux/pci_regs.h | 1 + |
| 3 files changed, 16 insertions(+), 1 deletion(-) |
| |
| --- a/drivers/pci/pcie/aspm.c |
| +++ b/drivers/pci/pcie/aspm.c |
| @@ -510,6 +510,7 @@ static int pcie_aspm_sanity_check(struct |
| { |
| 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 |
| 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, |
| + ®32); |
| + 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; |
| } |
| --- a/drivers/pci/probe.c |
| +++ b/drivers/pci/probe.c |
| @@ -1047,7 +1047,8 @@ int pci_scan_slot(struct pci_bus *bus, i |
| } |
| } |
| |
| - if (bus->self) |
| + /* only one slot has pcie device */ |
| + if (bus->self && nr) |
| pcie_aspm_init_link_state(bus->self); |
| |
| return nr; |
| --- a/include/linux/pci_regs.h |
| +++ b/include/linux/pci_regs.h |
| @@ -373,6 +373,7 @@ |
| #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 */ |