VMD PCH rootbus primary number is 0x80 and pci_scan_bridge_extend()
cannot assign it as "hard-wired to 0" and marks setup as broken. To
avoid this, PCH bus number has to be the same as PCH primary number.
Suggested-by: Nirmal Patel <nirmal.patel@xxxxxxxxxxxxxxx>
Reviewed-by: Mariusz Tkaczyk <mariusz.tkaczyk@xxxxxxxxxxxxxxx>
Signed-off-by: Szymon Durawa <szymon.durawa@xxxxxxxxxxxxxxx>
---
drivers/pci/controller/vmd.c | 26 ++++++++++++++++++++++++--
1 file changed, 24 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c
index 842b70a21325..bb47e0a76c89 100755
--- a/drivers/pci/controller/vmd.c
+++ b/drivers/pci/controller/vmd.c
@@ -404,8 +404,22 @@ static inline u8 vmd_has_pch_rootbus(struct vmd_dev *vmd)
static void __iomem *vmd_cfg_addr(struct vmd_dev *vmd, struct pci_bus *bus,
unsigned int devfn, int reg, int len)
{
- unsigned int busnr_ecam = bus->number - vmd->busn_start[VMD_BUS_0];
- u32 offset = PCIE_ECAM_OFFSET(busnr_ecam, devfn, reg);
+ unsigned char bus_number;
+ unsigned int busnr_ecam;
+ u32 offset;
+
+ /*
+ * VMD WA: for PCH rootbus, bus number is set to VMD_PRIMARY_PCH_BUS
+ * (see comment in vmd_create_pch_bus()) but original value is 0xE1
+ * which is stored in vmd->busn_start[VMD_BUS_1].
+ */
+ if (vmd_has_pch_rootbus(vmd) && bus->number == VMD_PRIMARY_PCH_BUS)
+ bus_number = vmd->busn_start[VMD_BUS_1];
+ else
+ bus_number = bus->number;
+
+ busnr_ecam = bus_number - vmd->busn_start[VMD_BUS_0];
+ offset = PCIE_ECAM_OFFSET(busnr_ecam, devfn, reg);
if (offset + len >= resource_size(&vmd->dev->resource[VMD_CFGBAR]))
return NULL;
@@ -1023,6 +1037,14 @@ static int vmd_create_pch_bus(struct vmd_dev *vmd, struct pci_sysdata *sd,
*/
vmd->bus[VMD_BUS_1]->primary = VMD_PRIMARY_PCH_BUS;
+ /* This is a workaround for pci_scan_bridge_extend() code.
+ * It assigns setup as broken when primary != bus->number and
+ * for PCH rootbus primary is not "hard-wired to 0".
+ * To avoid this, vmd->bus[VMD_BUS_1]->number and
+ * vmd->bus[VMD_BUS_1]->primary are updated to the same value.
+ */
+ vmd->bus[VMD_BUS_1]->number = VMD_PRIMARY_PCH_BUS;
+
vmd_copy_host_bridge_flags(
pci_find_host_bridge(vmd->dev->bus),
to_pci_host_bridge(vmd->bus[VMD_BUS_1]->bridge));
--
2.39.3
