Commit 2e122418 authored by Jon Derrick's avatar Jon Derrick Committed by Bjorn Helgaas
Browse files

PCI: vmd: Create bus offset configuration helper 

Move the bus offset configuration discovery code to a new helper.  Modify
the bus offset 2-bit decode switch to have a 0 case and a default error
case, just in case the field is expanded in future hardware.

Link: https://lore.kernel.org/r/20200728194945.14126-3-jonathan.derrick@intel.com


Signed-off-by: default avatarJon Derrick <jonathan.derrick@intel.com>
Signed-off-by: default avatarLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: default avatarAndy Shevchenko <andriy.shevchenko@intel.com>
parent 030109c0

drivers/pci/controller/vmd.c

+32 −21
Original line number Diff line number Diff line
@@ -471,6 +471,35 @@ static int vmd_get_phys_offsets(struct vmd_dev *vmd, bool native_hint, 
	return 0;

}



static int vmd_get_bus_number_start(struct vmd_dev *vmd)

{

	struct pci_dev *dev = vmd->dev;

	u16 reg;



	pci_read_config_word(dev, PCI_REG_VMCAP, &reg);

	if (BUS_RESTRICT_CAP(reg)) {

		pci_read_config_word(dev, PCI_REG_VMCONFIG, &reg);



		switch (BUS_RESTRICT_CFG(reg)) {

		case 0:

			vmd->busn_start = 0;

			break;

		case 1:

			vmd->busn_start = 128;

			break;

		case 2:

			vmd->busn_start = 224;

			break;

		default:

			pci_err(dev, "Unknown Bus Offset Setting (%d)\n",

				BUS_RESTRICT_CFG(reg));

			return -ENODEV;

		}

	}



	return 0;

}



static int vmd_enable_domain(struct vmd_dev *vmd, unsigned long features)

{

	struct pci_sysdata *sd = &vmd->sysdata;
@@ -506,27 +535,9 @@ static int vmd_enable_domain(struct vmd_dev *vmd, unsigned long features) 
	 * limits the bus range to between 0-127, 128-255, or 224-255

	 */

	if (features & VMD_FEAT_HAS_BUS_RESTRICTIONS) {

		u16 reg16;



		pci_read_config_word(vmd->dev, PCI_REG_VMCAP, &reg16);

		if (BUS_RESTRICT_CAP(reg16)) {

			pci_read_config_word(vmd->dev, PCI_REG_VMCONFIG,

					     &reg16);



			switch (BUS_RESTRICT_CFG(reg16)) {

			case 1:

				vmd->busn_start = 128;

				break;

			case 2:

				vmd->busn_start = 224;

				break;

			case 3:

				pci_err(vmd->dev, "Unknown Bus Offset Setting\n");

				return -ENODEV;

			default:

				break;

			}

		}

		ret = vmd_get_bus_number_start(vmd);

		if (ret)

			return ret;

	}



	res = &vmd->dev->resource[VMD_CFGBAR];

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