[PULL 07/17] vfio/igd: add macro for declaring mirrored registers

[Cédric Le Goater]

From: Tomita Moeko <tomitamoeko@gmail.com>

igd devices have multipe registers mirroring mmio address and pci
config space, more than a single BDSM register. To support this,
the read/write functions are made common and a macro is defined to
simplify the declaration of MemoryRegionOps.

Signed-off-by: Tomita Moeko <tomitamoeko@gmail.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Link: 20241206122749.9893-8-tomitamoeko@gmail.com">https://lore.kernel.org/r/20241206122749.9893-8-tomitamoeko@gmail.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
---
 hw/vfio/igd.c | 60 ++++++++++++++++++++++++++++++---------------------
 1 file changed, 36 insertions(+), 24 deletions(-)

diff --git a/hw/vfio/igd.c b/hw/vfio/igd.c
index 
49b65477767308cab3ce1f4e5b3bd77b90f42831..18d159aa8ecde3bb384dd6d3bd90e2110434335b
 100644
--- a/hw/vfio/igd.c
+++ b/hw/vfio/igd.c
@@ -421,16 +421,9 @@ static const MemoryRegionOps vfio_igd_index_quirk = {
     .endianness = DEVICE_LITTLE_ENDIAN,
 };
 
-#define IGD_BDSM_MMIO_OFFSET 0x1080C0
-
-static uint64_t vfio_igd_quirk_bdsm_read(void *opaque,
-                                          hwaddr addr, unsigned size)
+static uint64_t vfio_igd_pci_config_read(VFIOPCIDevice *vdev, uint64_t offset,
+                                         unsigned size)
 {
-    VFIOPCIDevice *vdev = opaque;
-    uint64_t offset;
-
-    offset = IGD_BDSM_GEN11 + addr;
-
     switch (size) {
     case 1:
         return pci_get_byte(vdev->pdev.config + offset);
@@ -441,21 +434,17 @@ static uint64_t vfio_igd_quirk_bdsm_read(void *opaque,
     case 8:
         return pci_get_quad(vdev->pdev.config + offset);
     default:
-        hw_error("igd: unsupported read size, %u bytes", size);
+        hw_error("igd: unsupported pci config read at %lx, size %u",
+                 offset, size);
         break;
     }
 
     return 0;
 }
 
-static void vfio_igd_quirk_bdsm_write(void *opaque, hwaddr addr,
-                                       uint64_t data, unsigned size)
+static void vfio_igd_pci_config_write(VFIOPCIDevice *vdev, uint64_t offset,
+                                      uint64_t data, unsigned size)
 {
-    VFIOPCIDevice *vdev = opaque;
-    uint64_t offset;
-
-    offset = IGD_BDSM_GEN11 + addr;
-
     switch (size) {
     case 1:
         pci_set_byte(vdev->pdev.config + offset, data);
@@ -470,17 +459,39 @@ static void vfio_igd_quirk_bdsm_write(void *opaque, 
hwaddr addr,
         pci_set_quad(vdev->pdev.config + offset, data);
         break;
     default:
-        hw_error("igd: unsupported read size, %u bytes", size);
+        hw_error("igd: unsupported pci config write at %lx, size %u",
+                 offset, size);
         break;
     }
 }
 
-static const MemoryRegionOps vfio_igd_bdsm_quirk = {
-    .read = vfio_igd_quirk_bdsm_read,
-    .write = vfio_igd_quirk_bdsm_write,
-    .endianness = DEVICE_LITTLE_ENDIAN,
+#define VFIO_IGD_QUIRK_MIRROR_REG(reg, name)                            \
+static uint64_t vfio_igd_quirk_read_##name(void *opaque,                \
+                                           hwaddr addr, unsigned size)  \
+{                                                                       \
+    VFIOPCIDevice *vdev = opaque;                                       \
+                                                                        \
+    return vfio_igd_pci_config_read(vdev, reg + addr, size);            \
+}                                                                       \
+                                                                        \
+static void vfio_igd_quirk_write_##name(void *opaque, hwaddr addr,      \
+                                        uint64_t data, unsigned size)   \
+{                                                                       \
+    VFIOPCIDevice *vdev = opaque;                                       \
+                                                                        \
+    vfio_igd_pci_config_write(vdev, reg + addr, data, size);            \
+}                                                                       \
+                                                                        \
+static const MemoryRegionOps vfio_igd_quirk_mirror_##name = {           \
+    .read = vfio_igd_quirk_read_##name,                                 \
+    .write = vfio_igd_quirk_write_##name,                               \
+    .endianness = DEVICE_LITTLE_ENDIAN,                                 \
 };
 
+VFIO_IGD_QUIRK_MIRROR_REG(IGD_BDSM_GEN11, bdsm)
+
+#define IGD_BDSM_MMIO_OFFSET    0x1080C0
+
 void vfio_probe_igd_bar0_quirk(VFIOPCIDevice *vdev, int nr)
 {
     VFIOQuirk *quirk;
@@ -510,8 +521,9 @@ void vfio_probe_igd_bar0_quirk(VFIOPCIDevice *vdev, int nr)
     quirk = vfio_quirk_alloc(1);
     quirk->data = vdev;
 
-    memory_region_init_io(&quirk->mem[0], OBJECT(vdev), &vfio_igd_bdsm_quirk,
-                          vdev, "vfio-igd-bdsm-quirk", 8);
+    memory_region_init_io(&quirk->mem[0], 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[0],
                                         1);
-- 
2.47.1