[RFC 1/3] virtio-gpu: hostmem

[Antonio Caggiano]

From: Gerd Hoffmann <kraxel@redhat.com>

Use VIRTIO_GPU_SHM_ID_HOST_VISIBLE as id for virtio-gpu.

Signed-off-by: Antonio Caggiano <antonio.caggiano@collabora.com>
---
 hw/display/virtio-gpu-pci.c    | 14 ++++++++++++++
 hw/display/virtio-gpu.c        |  1 +
 hw/display/virtio-vga.c        | 32 +++++++++++++++++++++++---------
 include/hw/virtio/virtio-gpu.h |  5 +++++
 4 files changed, 43 insertions(+), 9 deletions(-)

diff --git a/hw/display/virtio-gpu-pci.c b/hw/display/virtio-gpu-pci.c
index e36eee0c40..a79bd751b2 100644
--- a/hw/display/virtio-gpu-pci.c
+++ b/hw/display/virtio-gpu-pci.c
@@ -33,6 +33,20 @@ static void virtio_gpu_pci_base_realize(VirtIOPCIProxy 
*vpci_dev, Error **errp)
     DeviceState *vdev = DEVICE(g);
     int i;
 
+    if (virtio_gpu_hostmem_enabled(g->conf)) {
+        vpci_dev->msix_bar_idx = 1;
+        vpci_dev->modern_mem_bar_idx = 2;
+        memory_region_init(&g->hostmem, OBJECT(g), "virtio-gpu-hostmem",
+                           g->conf.hostmem);
+        pci_register_bar(&vpci_dev->pci_dev, 4,
+                         PCI_BASE_ADDRESS_SPACE_MEMORY |
+                         PCI_BASE_ADDRESS_MEM_PREFETCH |
+                         PCI_BASE_ADDRESS_MEM_TYPE_64,
+                         &g->hostmem);
+        virtio_pci_add_shm_cap(vpci_dev, 4, 0, g->conf.hostmem, 
VIRTIO_GPU_SHM_ID_HOST_VISIBLE);
+    }
+
+    qdev_set_parent_bus(vdev, BUS(&vpci_dev->bus), errp);
     virtio_pci_force_virtio_1(vpci_dev);
     if (!qdev_realize(vdev, BUS(&vpci_dev->bus), errp)) {
         return;
diff --git a/hw/display/virtio-gpu.c b/hw/display/virtio-gpu.c
index 182e0868b0..63eff0e697 100644
--- a/hw/display/virtio-gpu.c
+++ b/hw/display/virtio-gpu.c
@@ -1418,6 +1418,7 @@ static Property virtio_gpu_properties[] = {
                      256 * MiB),
     DEFINE_PROP_BIT("blob", VirtIOGPU, parent_obj.conf.flags,
                     VIRTIO_GPU_FLAG_BLOB_ENABLED, false),
+    DEFINE_PROP_SIZE("hostmem", VirtIOGPU, parent_obj.conf.hostmem, 0),
     DEFINE_PROP_END_OF_LIST(),
 };
 
diff --git a/hw/display/virtio-vga.c b/hw/display/virtio-vga.c
index 9e57f61e9e..ca841a0799 100644
--- a/hw/display/virtio-vga.c
+++ b/hw/display/virtio-vga.c
@@ -125,16 +125,30 @@ static void virtio_vga_base_realize(VirtIOPCIProxy 
*vpci_dev, Error **errp)
     pci_register_bar(&vpci_dev->pci_dev, 0,
                      PCI_BASE_ADDRESS_MEM_PREFETCH, &vga->vram);
 
-    /*
-     * Configure virtio bar and regions
-     *
-     * We use bar #2 for the mmio regions, to be compatible with stdvga.
-     * virtio regions are moved to the end of bar #2, to make room for
-     * the stdvga mmio registers at the start of bar #2.
-     */
-    vpci_dev->modern_mem_bar_idx = 2;
-    vpci_dev->msix_bar_idx = 4;
     vpci_dev->modern_io_bar_idx = 5;
+  
+    if (!virtio_gpu_hostmem_enabled(g->conf)) {
+        /*
+        * Configure virtio bar and regions
+        *
+        * We use bar #2 for the mmio regions, to be compatible with stdvga.
+        * virtio regions are moved to the end of bar #2, to make room for
+        * the stdvga mmio registers at the start of bar #2.
+        */
+        vpci_dev->modern_mem_bar_idx = 2;
+        vpci_dev->msix_bar_idx = 4;
+    } else {
+        vpci_dev->msix_bar_idx = 1;
+        vpci_dev->modern_mem_bar_idx = 2;
+        memory_region_init(&g->hostmem, OBJECT(g), "virtio-gpu-hostmem",
+                           g->conf.hostmem);
+        pci_register_bar(&vpci_dev->pci_dev, 4,
+                         PCI_BASE_ADDRESS_SPACE_MEMORY |
+                         PCI_BASE_ADDRESS_MEM_PREFETCH |
+                         PCI_BASE_ADDRESS_MEM_TYPE_64,
+                         &g->hostmem);
+        virtio_pci_add_shm_cap(vpci_dev, 4, 0, g->conf.hostmem, 
VIRTIO_GPU_SHM_ID_HOST_VISIBLE);
+    }
 
     if (!(vpci_dev->flags & VIRTIO_PCI_FLAG_PAGE_PER_VQ)) {
         /*
diff --git a/include/hw/virtio/virtio-gpu.h b/include/hw/virtio/virtio-gpu.h
index 24c6628944..835ebcb1a0 100644
--- a/include/hw/virtio/virtio-gpu.h
+++ b/include/hw/virtio/virtio-gpu.h
@@ -102,12 +102,15 @@ enum virtio_gpu_base_conf_flags {
     (_cfg.flags & (1 << VIRTIO_GPU_FLAG_DMABUF_ENABLED))
 #define virtio_gpu_blob_enabled(_cfg) \
     (_cfg.flags & (1 << VIRTIO_GPU_FLAG_BLOB_ENABLED))
+#define virtio_gpu_hostmem_enabled(_cfg) \
+    (_cfg.hostmem > 0)
 
 struct virtio_gpu_base_conf {
     uint32_t max_outputs;
     uint32_t flags;
     uint32_t xres;
     uint32_t yres;
+    uint64_t hostmem;
 };
 
 struct virtio_gpu_ctrl_command {
@@ -131,6 +134,8 @@ struct VirtIOGPUBase {
     int renderer_blocked;
     int enable;
 
+    MemoryRegion hostmem;
+
     struct virtio_gpu_scanout scanout[VIRTIO_GPU_MAX_SCANOUTS];
 
     int enabled_output_bitmask;
-- 
2.30.2