Use PCI Express Capability access functions to simplify this code a bit. For non-PCIe devices or pre-PCIe 3.0 devices that don't implement the Link Capabilities 2 register, pcie_capability_read_dword() reads a zero.
Since we're only testing whether the bits we care about are set, there's no need to mask out the other bits we *don't* care about.
Signed-off-by: Bjorn Helgaas bhelgaas@google.com --- drivers/gpu/drm/drm_pci.c | 21 +++++---------------- 1 files changed, 5 insertions(+), 16 deletions(-)
diff --git a/drivers/gpu/drm/drm_pci.c b/drivers/gpu/drm/drm_pci.c index 50e26f2..86102a0 100644 --- a/drivers/gpu/drm/drm_pci.c +++ b/drivers/gpu/drm/drm_pci.c @@ -469,41 +469,30 @@ EXPORT_SYMBOL(drm_pci_exit); int drm_pcie_get_speed_cap_mask(struct drm_device *dev, u32 *mask) { struct pci_dev *root; - int pos; - u32 lnkcap = 0, lnkcap2 = 0; + u32 lnkcap, lnkcap2;
*mask = 0; if (!dev->pdev) return -EINVAL;
- if (!pci_is_pcie(dev->pdev)) - return -EINVAL; - root = dev->pdev->bus->self;
- pos = pci_pcie_cap(root); - if (!pos) - return -EINVAL; - /* we've been informed via and serverworks don't make the cut */ if (root->vendor == PCI_VENDOR_ID_VIA || root->vendor == PCI_VENDOR_ID_SERVERWORKS) return -EINVAL;
- pci_read_config_dword(root, pos + PCI_EXP_LNKCAP, &lnkcap); - pci_read_config_dword(root, pos + PCI_EXP_LNKCAP2, &lnkcap2); - - lnkcap &= PCI_EXP_LNKCAP_SLS; - lnkcap2 &= 0xfe; + pcie_capability_read_dword(root, PCI_EXP_LNKCAP, &lnkcap); + pcie_capability_read_dword(root, PCI_EXP_LNKCAP2, &lnkcap2);
- if (lnkcap2) { /* PCIE GEN 3.0 */ + if (lnkcap2) { /* PCIe r3.0-compliant */ if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_2_5GB) *mask |= DRM_PCIE_SPEED_25; if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_5_0GB) *mask |= DRM_PCIE_SPEED_50; if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_8_0GB) *mask |= DRM_PCIE_SPEED_80; - } else { + } else { /* pre-r3.0 */ if (lnkcap & PCI_EXP_LNKCAP_SLS_2_5GB) *mask |= DRM_PCIE_SPEED_25; if (lnkcap & PCI_EXP_LNKCAP_SLS_5_0GB)