In this patch we replace our "dummy" Graphics Output Protocol interface
with the real one. We exploit that EFI_GRAPHICS_OUTPUT_BLT_PIXEL and
VirtioGpuFormatB8G8R8X8Unorm have identical representations; this lets us
forego any pixel format conversions in the guest. For messaging the VirtIo
GPU device, we use the primitives introduced in the previous patch.
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Ref: https://tianocore.acgmultimedia.com/show_bug.cgi?id=66
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
This patch implements the steps listed in section "3.1.1 Driver
Requirements: Device Initialization" of the Virtio V1.0 Committee Spec 04.
The VirtIo GPU is brought up in VirtioGpuDriverBindingStart(), and down in
VirtioGpuDriverBindingStop().
We also add an ExitBootServices() callback that resets the device. This
ensures that the device model abandons any guest memory areas when we
transfer control to the guest OS.
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Ref: https://tianocore.acgmultimedia.com/show_bug.cgi?id=66
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
This patch adds the skeleton of the driver: it implements the Component
Name 2 Protocol and the Driver Binding Protocol, in accordance with the
generic and GOP-specific requirements set forth in the UEFI spec and the
Driver Writers' Guide.
The basic idea is that VGPU_DEV abstracts the virtio GPU device, while the
single VGPU_GOP that we intend to support at this point stands for "head"
(aka "scanout") #0.
For now, the Virtio Device Protocol is only used for driver binding; no
actual virtio operations are done yet. Similarly, we use a "dummy" GOP
GUID and protocol structure (a plain UINT8 object) for now, so that
GOP-consuming drivers don't look at what we produce just yet.
The driver is a bit different from the other virtio device drivers written
thus far:
- It implements the GetControllerName() member of the Component Name 2
Protocol. (Formatting helpful names is recommended by UEFI.) As a "best
effort", we format the PCI BDF into the name (a PCI backend is not
guaranteed by VIRTIO_DEVICE_PROTOCOL). It should provide a more friendly
experience in the shell and elsewhere.
- This driver seeks to support all RemainingDevicePath cases:
- NULL: produce all (= one) child handles (= VGPU_GOP heads) at once,
- End of Device Path Node: produce no child handles,
- specific ACPI ADR Node: check if it's supportable, and produce it
(only one specific child controller is supported).
This is one of the reasons for separating VGPU_GOP from VGPU_DEV.
The driver is a hybrid driver: it produces both child handles (one, to be
exact), but also installs a structure (VGPU_DEV) directly on the VirtIo
controller handle, using gEfiCallerIdGuid as protocol GUID. This is a
trick I've seen elsewhere in edk2 (for example, TerminalDxe), and it is
necessary for the following reason:
In EFI_COMPONENT_NAME2_PROTOCOL.GetControllerName(), we must be able to
"cast down" a VirtIo ControllerHandle to our own private data structure
(VGPU_DEV). That's only possible if we install the structure directly on
the VirtIo ControllerHandle (thereby rendering the driver a hybrid
driver), because a child controller with our GOP implementation on it may
not exist / be passed in there.
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Ref: https://tianocore.acgmultimedia.com/show_bug.cgi?id=66
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Laszlo Ersek