Commit dd66cc2e authored by Bjorn Helgaas's avatar Bjorn Helgaas Committed by Dave Airlie
Browse files

drm/pci: Use PCI Express Capability accessors 



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: default avatarBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
parent f8acf6f4

drivers/gpu/drm/drm_pci.c

+5 −16
Original line number Diff line number Diff line
@@ -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)

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