Commit Graph

6 Commits

Author SHA1 Message Date
Hou Qiming
f79081b4b7 hw/display/ramfb: initialize fw-config space with xres/ yres
If xres / yres were specified in QEMU command line, write them as an initial
resolution to the fw-config space on guest reset, which a later BIOS / OVMF
patch can take advantage of.

Signed-off-by: HOU Qiming <hqm03ster@gmail.com>
Signed-off-by: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Message-id: 20190513115731.17588-4-marcel.apfelbaum@gmail.com
[fixed malformed patch]
Signed-off-by: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-05-24 09:10:29 +02:00
Hou Qiming
a9e0cb67b7 hw/display/ramfb: lock guest resolution after it's set
Only allow one resolution change per guest boot, which prevents a
crash when the guest writes garbage to the configuration space (e.g.
when rebooting).

Signed-off-by: HOU Qiming <hqm03ster@gmail.com>
Signed-off-by: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Message-id: 20190513115731.17588-3-marcel.apfelbaum@gmail.com
[fixed malformed patch]
Signed-off-by: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-05-24 09:10:29 +02:00
Hou Qiming
d57f252add hw/display/ramfb: fix guest memory un-mapping
Pulled back the `qemu_create_displaysurface_guestmem` function to create
the display surface so that the guest memory gets properly unmapped.

Signed-off-by: HOU Qiming <hqm03ster@gmail.com>
Signed-off-by: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Message-id: 20190513115731.17588-2-marcel.apfelbaum@gmail.com
[rename the new functions and use QEMU coding style]
Signed-off-by: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2019-05-24 09:10:29 +02:00
Gerd Hoffmann
9f5d9c19c7 ramfb: enable vgabios
Add vgabios binary to fw_cfg vgaroms.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2018-07-02 17:21:52 +02:00
Gerd Hoffmann
6b9b3c1e30 ramfb: fix overflow
> CID 1393621:    (OVERFLOW_BEFORE_WIDEN)
> Potentially overflowing expression "stride * s->height" with type "unsigned
> int" (32 bits, unsigned) is evaluated using +32-bit arithmetic, and then used
> in a context that expects an expression of type "hwaddr" (64 bits, unsigned).

Fix by changing stride from uint32_t to hwaddr.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 20180626083120.19515-1-kraxel@redhat.com
2018-06-26 16:04:01 +02:00
Gerd Hoffmann
995b30179b hw/display: add ramfb, a simple boot framebuffer living in guest ram
The boot framebuffer is expected to be configured by the firmware, so it
uses fw_cfg as interface.  Initialization goes as follows:

  (1) Check whenever etc/ramfb is present.
  (2) Allocate framebuffer from RAM.
  (3) Fill struct RAMFBCfg, write it to etc/ramfb.

Done.  You can write stuff to the framebuffer now, and it should appear
automagically on the screen.

Note that this isn't very efficient because it does a full display
update on each refresh.  No dirty tracking.  Dirty tracking would have
to be active for the whole ram slot, so that wouldn't be very efficient
either.  For a boot display which is active for a short time only this
isn't a big deal.  As permanent guest display something better should be
used (if possible).

This is the ramfb core code.  Some windup is needed for display devices
which want have a ramfb boot display.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Message-id: 20180613122948.18149-2-kraxel@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2018-06-18 11:22:15 +02:00