Commit 757bfaa2 authored by Yicong Yang's avatar Yicong Yang Committed by Bjorn Helgaas
Browse files

PCI: Add PCIE_LNKCAP2_SLS2SPEED() macro 

Add PCIE_LNKCAP2_SLS2SPEED macro for transforming raw Link Capabilities 2
values to the pci_bus_speed. This is next to PCIE_SPEED2MBS_ENC() to make
it easier to update both places when adding support for new speeds.

Link: https://lore.kernel.org/r/1581937984-40353-10-git-send-email-yangyicong@hisilicon.com


Signed-off-by: default avatarYicong Yang <yangyicong@hisilicon.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent 6348a34d

drivers/pci/pci.c

+4 −13
Original line number Diff line number Diff line
@@ -5784,19 +5784,10 @@ enum pci_bus_speed pcie_get_speed_cap(struct pci_dev *dev) 
	 * where only 2.5 GT/s and 5.0 GT/s speeds were defined.

	 */

	pcie_capability_read_dword(dev, PCI_EXP_LNKCAP2, &lnkcap2);

	if (lnkcap2) { /* PCIe r3.0-compliant */

		if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_32_0GB)

			return PCIE_SPEED_32_0GT;

		else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_16_0GB)

			return PCIE_SPEED_16_0GT;

		else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_8_0GB)

			return PCIE_SPEED_8_0GT;

		else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_5_0GB)

			return PCIE_SPEED_5_0GT;

		else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_2_5GB)

			return PCIE_SPEED_2_5GT;

		return PCI_SPEED_UNKNOWN;

	}



	/* PCIe r3.0-compliant */

	if (lnkcap2)

		return PCIE_LNKCAP2_SLS2SPEED(lnkcap2);



	pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &lnkcap);

	if ((lnkcap & PCI_EXP_LNKCAP_SLS) == PCI_EXP_LNKCAP_SLS_5_0GB)

drivers/pci/pci.h

+9 −0
Original line number Diff line number Diff line
@@ -292,6 +292,15 @@ void pci_disable_bridge_window(struct pci_dev *dev); 
struct pci_bus *pci_bus_get(struct pci_bus *bus);

void pci_bus_put(struct pci_bus *bus);



/* PCIe link information from Link Capabilities 2 */

#define PCIE_LNKCAP2_SLS2SPEED(lnkcap2) \

	((lnkcap2) & PCI_EXP_LNKCAP2_SLS_32_0GB ? PCIE_SPEED_32_0GT : \

	 (lnkcap2) & PCI_EXP_LNKCAP2_SLS_16_0GB ? PCIE_SPEED_16_0GT : \

	 (lnkcap2) & PCI_EXP_LNKCAP2_SLS_8_0GB ? PCIE_SPEED_8_0GT : \

	 (lnkcap2) & PCI_EXP_LNKCAP2_SLS_5_0GB ? PCIE_SPEED_5_0GT : \

	 (lnkcap2) & PCI_EXP_LNKCAP2_SLS_2_5GB ? PCIE_SPEED_2_5GT : \

	 PCI_SPEED_UNKNOWN)



/* PCIe speed to Mb/s reduced by encoding overhead */

#define PCIE_SPEED2MBS_ENC(speed) \

	((speed) == PCIE_SPEED_32_0GT ? 32000*128/130 : \

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