提交 f4297784 编写于 作者: D Dave Airlie

drm/pci: add support for getting the supported link bw.

This should work for PCIE3.0 as well.
Signed-off-by: NDave Airlie <airlied@redhat.com>
上级 cdcac9cd
......@@ -465,3 +465,52 @@ void drm_pci_exit(struct drm_driver *driver, struct pci_driver *pdriver)
DRM_INFO("Module unloaded\n");
}
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, 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;
if (lnkcap2) { /* PCIE GEN 3.0 */
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 {
if (lnkcap & 1)
*mask |= DRM_PCIE_SPEED_25;
if (lnkcap & 2)
*mask |= DRM_PCIE_SPEED_50;
}
DRM_INFO("probing gen 2 caps for device %x:%x = %x/%x\n", root->vendor, root->device, lnkcap, lnkcap2);
return 0;
}
EXPORT_SYMBOL(drm_pcie_get_speed_cap_mask);
......@@ -1761,6 +1761,11 @@ extern int drm_get_pci_dev(struct pci_dev *pdev,
const struct pci_device_id *ent,
struct drm_driver *driver);
#define DRM_PCIE_SPEED_25 1
#define DRM_PCIE_SPEED_50 2
#define DRM_PCIE_SPEED_80 4
extern int drm_pcie_get_speed_cap_mask(struct drm_device *dev, u32 *speed_mask);
/* platform section */
extern int drm_platform_init(struct drm_driver *driver, struct platform_device *platform_device);
......
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