[PATCH 1/6] PCI: vmd: Create physical offset helper

From: Jon Derrick
Date: Tue Jul 28 2020 - 16:07:11 EST


Moves the guest-passthrough physical offset discovery code to a new
helper. No functional changes.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxx>
Signed-off-by: Jon Derrick <jonathan.derrick@xxxxxxxxx>
---
drivers/pci/controller/vmd.c | 105 +++++++++++++++++++++--------------
1 file changed, 62 insertions(+), 43 deletions(-)

diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c
index f69ef8c89f72..44b2db789eff 100644
--- a/drivers/pci/controller/vmd.c
+++ b/drivers/pci/controller/vmd.c
@@ -417,6 +417,60 @@ static int vmd_find_free_domain(void)
return domain + 1;
}

+static int vmd_get_phys_offsets(struct vmd_dev *vmd, bool native_hint,
+ resource_size_t *offset1,
+ resource_size_t *offset2)
+{
+ struct pci_dev *dev = vmd->dev;
+ u64 phys1, phys2;
+
+ if (native_hint) {
+ u32 vmlock;
+ int ret;
+
+ ret = pci_read_config_dword(dev, PCI_REG_VMLOCK, &vmlock);
+ if (ret || vmlock == ~0)
+ return -ENODEV;
+
+ if (MB2_SHADOW_EN(vmlock)) {
+ void __iomem *membar2;
+
+ membar2 = pci_iomap(dev, VMD_MEMBAR2, 0);
+ if (!membar2)
+ return -ENOMEM;
+ phys1 = readq(membar2 + MB2_SHADOW_OFFSET);
+ phys2 = readq(membar2 + MB2_SHADOW_OFFSET + 8);
+ pci_iounmap(dev, membar2);
+ } else
+ return 0;
+ } else {
+ /* Hypervisor-Emulated Vendor-Specific Capability */
+ int pos = pci_find_capability(dev, PCI_CAP_ID_VNDR);
+ u32 reg, regu;
+
+ pci_read_config_dword(dev, pos + 4, &reg);
+
+ /* "SHDW" */
+ if (pos && reg == 0x53484457) {
+ pci_read_config_dword(dev, pos + 8, &reg);
+ pci_read_config_dword(dev, pos + 12, &regu);
+ phys1 = (u64) regu << 32 | reg;
+
+ pci_read_config_dword(dev, pos + 16, &reg);
+ pci_read_config_dword(dev, pos + 20, &regu);
+ phys2 = (u64) regu << 32 | reg;
+ } else
+ return 0;
+ }
+
+ *offset1 = dev->resource[VMD_MEMBAR1].start -
+ (phys1 & PCI_BASE_ADDRESS_MEM_MASK);
+ *offset2 = dev->resource[VMD_MEMBAR2].start -
+ (phys2 & PCI_BASE_ADDRESS_MEM_MASK);
+
+ return 0;
+}
+
static int vmd_enable_domain(struct vmd_dev *vmd, unsigned long features)
{
struct pci_sysdata *sd = &vmd->sysdata;
@@ -428,6 +482,7 @@ static int vmd_enable_domain(struct vmd_dev *vmd, unsigned long features)
resource_size_t offset[2] = {0};
resource_size_t membar2_offset = 0x2000;
struct pci_bus *child;
+ int ret;

/*
* Shadow registers may exist in certain VMD device ids which allow
@@ -436,50 +491,14 @@ static int vmd_enable_domain(struct vmd_dev *vmd, unsigned long features)
* or 0, depending on an enable bit in the VMD device.
*/
if (features & VMD_FEAT_HAS_MEMBAR_SHADOW) {
- u32 vmlock;
- int ret;
-
membar2_offset = MB2_SHADOW_OFFSET + MB2_SHADOW_SIZE;
- ret = pci_read_config_dword(vmd->dev, PCI_REG_VMLOCK, &vmlock);
- if (ret || vmlock == ~0)
- return -ENODEV;
-
- if (MB2_SHADOW_EN(vmlock)) {
- void __iomem *membar2;
-
- membar2 = pci_iomap(vmd->dev, VMD_MEMBAR2, 0);
- if (!membar2)
- return -ENOMEM;
- offset[0] = vmd->dev->resource[VMD_MEMBAR1].start -
- (readq(membar2 + MB2_SHADOW_OFFSET) &
- PCI_BASE_ADDRESS_MEM_MASK);
- offset[1] = vmd->dev->resource[VMD_MEMBAR2].start -
- (readq(membar2 + MB2_SHADOW_OFFSET + 8) &
- PCI_BASE_ADDRESS_MEM_MASK);
- pci_iounmap(vmd->dev, membar2);
- }
- }
-
- if (features & VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP) {
- int pos = pci_find_capability(vmd->dev, PCI_CAP_ID_VNDR);
- u32 reg, regu;
-
- pci_read_config_dword(vmd->dev, pos + 4, &reg);
-
- /* "SHDW" */
- if (pos && reg == 0x53484457) {
- pci_read_config_dword(vmd->dev, pos + 8, &reg);
- pci_read_config_dword(vmd->dev, pos + 12, &regu);
- offset[0] = vmd->dev->resource[VMD_MEMBAR1].start -
- (((u64) regu << 32 | reg) &
- PCI_BASE_ADDRESS_MEM_MASK);
-
- pci_read_config_dword(vmd->dev, pos + 16, &reg);
- pci_read_config_dword(vmd->dev, pos + 20, &regu);
- offset[1] = vmd->dev->resource[VMD_MEMBAR2].start -
- (((u64) regu << 32 | reg) &
- PCI_BASE_ADDRESS_MEM_MASK);
- }
+ ret = vmd_get_phys_offsets(vmd, true, &offset[0], &offset[1]);
+ if (ret)
+ return ret;
+ } else if (features & VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP) {
+ ret = vmd_get_phys_offsets(vmd, false, &offset[0], &offset[1]);
+ if (ret)
+ return ret;
}

/*
--
2.27.0