[PATCH 7/8] vfio/igd: emulate BDSM in mmio bar0 for gen 6-10 devices

[Tomita Moeko]

A recent commit in i915 driver [1] claims the BDSM register at 0x1080c0
of mmio bar0 has been there since gen 6. Mirror this register to the 32
bit BDSM register at 0x5c in pci config space for gen6-10 devices.

[1] 
https://patchwork.freedesktop.org/patch/msgid/20240202224340.30647-7-ville.syrj...@linux.intel.com

Signed-off-by: Tomita Moeko <tomitamo...@gmail.com>
---
 hw/vfio/igd.c | 26 ++++++++++++++++++--------
 1 file changed, 18 insertions(+), 8 deletions(-)

diff --git a/hw/vfio/igd.c b/hw/vfio/igd.c
index 07700dce30..3fd822241d 100644
--- a/hw/vfio/igd.c
+++ b/hw/vfio/igd.c
@@ -482,7 +482,8 @@ static const MemoryRegionOps vfio_igd_quirk_mirror_##name = 
{           \
 };
 
 VFIO_IGD_QUIRK_MIRROR_REG(IGD_GMCH, ggc)
-VFIO_IGD_QUIRK_MIRROR_REG(IGD_BDSM_GEN11, bdsm)
+VFIO_IGD_QUIRK_MIRROR_REG(IGD_BDSM, bdsm)
+VFIO_IGD_QUIRK_MIRROR_REG(IGD_BDSM_GEN11, bdsm64)
 
 void vfio_probe_igd_bar0_quirk(VFIOPCIDevice *vdev, int nr)
 {
@@ -506,7 +507,7 @@ void vfio_probe_igd_bar0_quirk(VFIOPCIDevice *vdev, int nr)
      * into MMIO space and read from MMIO space by the Windows driver.
      */
     gen = igd_gen(vdev);
-    if (gen < 11) {
+    if (gen < 6) {
         return;
     }
 
@@ -520,12 +521,21 @@ void vfio_probe_igd_bar0_quirk(VFIOPCIDevice *vdev, int 
nr)
                                         IGD_GGC_MMIO_OFFSET, &quirk->mem[0],
                                         1);
 
-    memory_region_init_io(&quirk->mem[1], OBJECT(vdev),
-                          &vfio_igd_quirk_mirror_bdsm, vdev,
-                          "vfio-igd-bdsm-quirk", 8);
-    memory_region_add_subregion_overlap(vdev->bars[0].region.mem,
-                                        IGD_BDSM_MMIO_OFFSET, &quirk->mem[1],
-                                        1);
+    if (gen < 11) {
+        memory_region_init_io(&quirk->mem[1], OBJECT(vdev),
+                              &vfio_igd_quirk_mirror_bdsm, vdev,
+                              "vfio-igd-bdsm-quirk", 4);
+        memory_region_add_subregion_overlap(vdev->bars[0].region.mem,
+                                            IGD_BDSM_MMIO_OFFSET,
+                                            &quirk->mem[1], 1);
+    } else {
+        memory_region_init_io(&quirk->mem[1], OBJECT(vdev),
+                              &vfio_igd_quirk_mirror_bdsm64, vdev,
+                              "vfio-igd-bdsm-quirk", 8);
+        memory_region_add_subregion_overlap(vdev->bars[0].region.mem,
+                                            IGD_BDSM_MMIO_OFFSET,
+                                            &quirk->mem[1], 1);
+    }
 
     QLIST_INSERT_HEAD(&vdev->bars[nr].quirks, quirk, next);
 }
-- 
2.45.2