It is common practice when implementing double-buffering on VideoCore
to do so by multiplying the height of the virtual buffer by the
number of virtual screens desired (i.e., two - in the case of
double-bufferring).
At present, this won't work in QEMU because the logic in
fb_use_offsets require that both the virtual width and height exceed
their physical counterparts.
This appears to be unintentional/a typo and indeed the comment
states; "Experimentally, the hardware seems to do this only if the
viewport size is larger than the physical screen". The
viewport/virtual size would be larger than the physical size if
either virtual dimension were larger than their physical counterparts
and not necessarily both.
Signed-off-by: SamJakob <me@samjakob.com>
Message-id: 20240713160353.62410-1-me@samjakob.com
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Remove dpy_cursor_define_supported() as it brings no benefit today and
it has a few inherent problems.
All graphical displays except egl-headless support cursor composition
without DMA-BUF, and egl-headless is meant to be used in conjunction
with another graphical display, so dpy_cursor_define_supported()
always returns true and meaningless.
Even if we add a new display without cursor composition in the future,
dpy_cursor_define_supported() will be problematic as a cursor display
fix for it because some display devices like virtio-gpu cannot tell the
lack of cursor composition capability to the guest and are unable to
utilize the value the function returns. Therefore, all non-headless
graphical displays must actually implement cursor composition for
correct cursor display.
Another problem with dpy_cursor_define_supported() is that it returns
true even if only some of the display listeners support cursor
composition, which is wrong unless all display listeners that lack
cursor composition is headless.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Phil Dennis-Jordan <phil@philjordan.eu>
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-ID: <20240715-cursor-v3-4-afa5b9492dbf@daynix.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
When using vhost-user-gpu with GL, qemu -display gtk doesn't show output
and prints: qemu: eglCreateImageKHR failed
Since commit 9ac06df8b ("virtio-gpu-udmabuf: correct naming of
QemuDmaBuf size properties"), egl_dmabuf_import_texture() uses
backing_{width,height} for the texture dimension.
Fixes: 9ac06df8b ("virtio-gpu-udmabuf: correct naming of QemuDmaBuf size properties")
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20240515105237.1074116-1-marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Boolean return value is reversed, to align with QEMU_ALLOCATED_FLAG, so
all callers must be adapted. Also rename share_surface variable in
vga_draw_graphic() to reduce confusion.
No functional change.
Suggested-by: Marc-André Lureau <marcandre.lureau@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-ID: <20240605131444.797896-4-kraxel@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
In case the display surface uses a shared buffer (i.e. uses vga vram
directly instead of a shadow) go unshare the buffer before clearing it.
This avoids vga memory corruption, which in turn fixes unblanking not
working properly with X11.
Cc: qemu-stable@nongnu.org
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2067
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-ID: <20240605131444.797896-2-kraxel@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Align the framebuffer backend with the other legacy ones,
register it via xen_backend_init() when '-vga xenfb' is
used. It is safe because MODULE_INIT_XEN_BACKEND is called
in xen_bus_realize(), long after CLI processing initialized
the vga_interface_type variable.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Paul Durrant <paul@xen.org>
Message-Id: <20240510104908.76908-8-philmd@linaro.org>
Keep XenDevOps structures in .rodata.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Paul Durrant <paul@xen.org>
Message-Id: <20240510104908.76908-5-philmd@linaro.org>
Commit dfcf74fa ("virtio-gpu: fix scanout migration post-load") broke
forward/backward version migration. Versioning of nested VMSD structures
is not straightforward, as the wire format doesn't have nested
structures versions. Introduce x-scanout-vmstate-version and a field
test to save/load appropriately according to the machine version.
Fixes: dfcf74fa ("virtio-gpu: fix scanout migration post-load")
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Fiona Ebner <f.ebner@proxmox.com>
Tested-by: Fiona Ebner <f.ebner@proxmox.com>
[fixed long lines]
Signed-off-by: Fabiano Rosas <farosas@suse.de>
This commit introduces utility functions for the creation and deallocation
of QemuDmaBuf instances. Additionally, it updates all relevant sections
of the codebase to utilize these new utility functions.
v7: remove prefix, "dpy_gl_" from all helpers
qemu_dmabuf_free() returns without doing anything if input is null
(Daniel P. Berrangé <berrange@redhat.com>)
call G_DEFINE_AUTOPTR_CLEANUP_FUNC for qemu_dmabuf_free()
(Daniel P. Berrangé <berrange@redhat.com>)
v8: Introduction of helpers was removed as those were already added
by the previous commit
v9: set dmabuf->allow_fences to 'true' when dmabuf is created in
virtio_gpu_create_dmabuf()/virtio-gpu-udmabuf.c
removed unnecessary spaces were accidently added in the patch,
'ui/console: Use qemu_dmabuf_new() a...'
v11: Calling qemu_dmabuf_close was removed as closing dmabuf->fd will be
done in qemu_dmabuf_free anyway.
(Daniel P. Berrangé <berrange@redhat.com>)
v12: --- Calling qemu_dmabuf_close separately as qemu_dmabuf_free doesn't
do it.
--- 'dmabuf' is now allocated space so it should be freed at the end of
dbus_scanout_texture
v13: --- Immediately free dmabuf after it is released to prevent possible
leaking of the ptr
(Marc-André Lureau <marcandre.lureau@redhat.com>)
--- Use g_autoptr macro to define *dmabuf for auto clean up instead of
calling qemu_dmabuf_free
(Marc-André Lureau <marcandre.lureau@redhat.com>)
v14: --- (vhost-user-gpu) Change qemu_dmabuf_free back to g_clear_pointer
as it was done because of some misunderstanding (v13).
--- (vhost-user-gpu) g->dmabuf[m->scanout_id] needs to be set to NULL
to prevent freed dmabuf to be accessed again in case if(fd==-1)break;
happens (before new dmabuf is allocated). Otherwise, it would cause
invalid memory access when the same function is executed. Also NULL
check should be done before qemu_dmabuf_close (it asserts dmabuf!=NULL.).
(Marc-André Lureau <marcandre.lureau@redhat.com>)
Suggested-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Cc: Philippe Mathieu-Daudé <philmd@linaro.org>
Cc: Daniel P. Berrangé <berrange@redhat.com>
Cc: Vivek Kasireddy <vivek.kasireddy@intel.com>
Signed-off-by: Dongwon Kim <dongwon.kim@intel.com>
Message-Id: <20240508175403.3399895-6-dongwon.kim@intel.com>
This commit updates all instances where fields within the QemuDmaBuf
struct are directly accessed, replacing them with calls to these new
helper functions.
v6: fix typos in helper names in ui/spice-display.c
v7: removed prefix, "dpy_gl_" from all helpers
v8: Introduction of helpers was removed as those were already added
by the previous commit
v11: -- Use new qemu_dmabuf_close() instead of close(qemu_dmabuf_get_fd()).
(Daniel P. Berrangé <berrange@redhat.com>)
-- Use new qemu_dmabuf_dup_fd() instead of dup(qemu_dmabuf_get_fd()).
(Daniel P. Berrangé <berrange@redhat.com>)
Suggested-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Cc: Philippe Mathieu-Daudé <philmd@linaro.org>
Cc: Daniel P. Berrangé <berrange@redhat.com>
Cc: Vivek Kasireddy <vivek.kasireddy@intel.com>
Signed-off-by: Dongwon Kim <dongwon.kim@intel.com>
Message-Id: <20240508175403.3399895-4-dongwon.kim@intel.com>
It is okay to register legacy backends in the middle of xen_bus_init().
All that the registration does is record the existence of the backend
in xenstore.
This makes it possible to remove them from the build without introducing
undefined symbols in xen_be_init(). It also removes the need for the
backend_register callback, whose only purpose is to avoid registering
nonfunctional backends.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240509170044.190795-8-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Basically all uses of GraphicHwOps are defining an instance of it, which requires the
full definition of the struct. It is pointless to have it in typedefs.h.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If virgl and opengl are not available, the build process creates a useless
libvirtio-vga-gl module that does not have any device in it. Follow the
example of virtio-vga-rutabaga and do not build the module at all in that
case.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This device implements the IM120417002 colors shield v1.1 for Arduino
(which relies on the DM163 8x3-channel led driving logic) and features
a simple display of an 8x8 RGB matrix. The columns of the matrix are
driven by the DM163 and the rows are driven externally.
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Arnaud Minier <arnaud.minier@telecom-paris.fr>
Signed-off-by: Inès Varhol <ines.varhol@telecom-paris.fr>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20240424200929.240921-2-ines.varhol@telecom-paris.fr
[PMM: updated to new reset hold method prototype]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
We usually check target endianess before swapping values,
so target_words_bigendian() declaration makes sense in
"exec/tswap.h" with the target swapping helpers.
Remove "hw/core/cpu.h" when it was only included to get
the target_words_bigendian() declaration.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Message-Id: <20231212123401.37493-16-philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
We pass a ResetType argument to the Resettable class enter
phase method, but we don't pass it to hold and exit, even though
the callsites have it readily available. This means that if
a device cared about the ResetType it would need to record it
in the enter phase method to use later on. Pass the type to
all three of the phase methods to avoid having to do that.
Commit created with
for dir in hw target include; do \
spatch --macro-file scripts/cocci-macro-file.h \
--sp-file scripts/coccinelle/reset-type.cocci \
--keep-comments --smpl-spacing --in-place \
--include-headers --dir $dir; done
and no manual edits.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@amd.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Luc Michel <luc.michel@amd.com>
Message-id: 20240412160809.1260625-5-peter.maydell@linaro.org
Take into account split screen mode close to wrap around, which is the
other special case for dirty memory region computation.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The depth == 0 and depth == 15 have to be special cased because
width * depth / 8 does not provide the correct scanline length.
However, thanks to the recent reorganization of vga_draw_graphic()
the correct value of VRAM bits per pixel is available in "bits".
Use it (via the same "bwidth" computation that is used later in
the function), thus restricting the slow path to the wraparound case.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Since the ramfb stubs are needed exactly when the Kconfig symbols are not
needed, move them to hw/display/ and compile them when ramfb.c is absent.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20240408155330.522792-14-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Horizontal pel panning bit 3 is only used in text mode. In graphics
mode, it can be treated as if it was zero, thus not extending the
dirty memory region.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When pel panning is active, one more byte is read from each of the VGA
memory planes. This has to be accounted in the computation of region_end,
otherwise vga_draw_graphic() fails an assertion:
qemu-system-i386: ../system/physmem.c:946: cpu_physical_memory_snapshot_get_dirty: Assertion `start + length <= snap->end' failed.
Reported-by: Helge Konetzka <hk@zapateado.de>
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2244
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move the computation of region_start and region_end after the value of
"bits" is known. This makes it possible to distinguish modes that
support horizontal pel panning from modes that do not.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
There are two sets of conditionals using the shift control bits: one to
verify the palette and adjust disp_width, one to compute the "v" and
"bits" variables. Merge them into one, with the extra benefit that
we now have the "bits" value available early and can use it to
compute region_end.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The current post-loading code for scanout has a FIXME: it doesn't take
the resource region/rect into account. But there is more, when adding
blob migration support in commit f66767f75c, I didn't realize that blob
resources could be used for scanouts. This situationn leads to a crash
during post-load, as they don't have an associated res->image.
virtio_gpu_do_set_scanout() handle all cases, but requires the
associated virtio_gpu_framebuffer, which is currently not saved during
migration.
Add a v2 of "virtio-gpu-one-scanout" with the framebuffer fields, so we
can restore blob scanouts, as well as fixing the existing FIXME.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Sebastian Ott <sebott@redhat.com>
When a variable is initialized to &struct->field, use it
in place. Rationale: while this makes the code more concise,
this also helps static analyzers.
Mechanical change using the following Coccinelle spatch script:
@@
type S, F;
identifier s, m, v;
@@
S *s;
...
F *v = &s->m;
<+...
- &s->m
+ v
...+>
Inspired-by: Zhao Liu <zhao1.liu@intel.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240129164514.73104-2-philmd@linaro.org>
Acked-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
[thuth: Dropped hunks that need a rebase, and fixed sizeof() in pmu_realize()]
Signed-off-by: Thomas Huth <thuth@redhat.com>
As the comment in qapi/error, dereferencing @errp requires
ERRP_GUARD():
* = Why, when and how to use ERRP_GUARD() =
*
* Without ERRP_GUARD(), use of the @errp parameter is restricted:
* - It must not be dereferenced, because it may be null.
...
* ERRP_GUARD() lifts these restrictions.
*
* To use ERRP_GUARD(), add it right at the beginning of the function.
* @errp can then be used without worrying about the argument being
* NULL or &error_fatal.
*
* Using it when it's not needed is safe, but please avoid cluttering
* the source with useless code.
But in macfb_nubus_realize(), @errp is dereferenced without
ERRP_GUARD():
ndc->parent_realize(dev, errp);
if (*errp) {
return;
}
Here we check *errp, because the ndc->parent_realize(), as a
DeviceClass.realize() callback, returns void. And since
macfb_nubus_realize(), also as a DeviceClass.realize(), doesn't get the
NULL @errp parameter, it hasn't triggered the bug that dereferencing the
NULL @errp.
To follow the requirement of @errp, add missing ERRP_GUARD() in
macfb_nubus_realize().
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240223085653.1255438-3-zhao1.liu@linux.intel.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Add new "select" and "imply" directives if needed. The resulting
config-devices.mak files are the same as before.
Builds without default devices will become much smaller
than before, and qtests fail (as expected, though suboptimal)
for mips64-softmmu because most tests do not use -nodefaults,
so remove it from build-without-defaults
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Split the sysbus version to a separate file so that it is not
included in PCI-only machines, and adjust Kconfig for machines
that do need sysbus-ohci. The copyrights are based on the
time and employer of balrog and Paul Brook's contributions.
While adjusting the SM501 dependency, move it to the right place
instead of keeping it in the R4D machine.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240223124406.234509-10-pbonzini@redhat.com>
[PMD: Rename some functions using 'ohci_sysbus_' prefix]
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Add the Exynos4210fimdState::'framebuffer-memory' property. Have
the board set it. We don't need to call sysbus_address_space()
anymore.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240226173805.289-5-philmd@linaro.org>
Add the PL110::'framebuffer-memory' property. Have the different
ARM boards set it. We don't need to call sysbus_address_space()
anymore.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240226173805.289-3-philmd@linaro.org>
When the Rutabaga GPU device frees resources, it calls
rutabaga_resource_unref for that resource_id. However, when the generic
VirtIOGPU functions destroys resources, it only removes the
virtio_gpu_simple_resource from the device's VirtIOGPU->reslist list.
The rutabaga resource associated with that resource_id is then leaked.
This commit overrides the resource_destroy class method introduced in
the previous commit to fix this.
Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Message-Id: <e3778e44c98a35839de2f4938e5355449fa3aa14.1706626470.git.manos.pitsidianakis@linaro.org>
Reviewed-by: Gurchetan Singh <gurchetansingh@chromium.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
When destroying/unrefing resources, devices such as virtio-gpu-rutabaga
need to do their own bookkeeping (free rutabaga resources that are
associated with the virtio_gpu_simple_resource).
This commit adds a class method so that virtio-gpu-rutabaga can override
it in the next commit.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Message-Id: <b0a86630c4d601f3a269fd7e08cfefc13bd4e219.1706626470.git.manos.pitsidianakis@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
While the VirtioGPU type has a reset_bh field to specify a reset
callback, it's never used. virtio_gpu_reset() calls the general
virtio_gpu_reset_bh() function for all devices that inherit from
VirtioGPU.
While no devices override reset_bh at the moment, a device reset might
require special logic for implementations in the future.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Message-Id: <87fb4fa72ce5b341a6f957513a00dcb79fd5997f.1706626470.git.manos.pitsidianakis@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
virgl_renderer_resource_get_info() returns errno and not -1 on error.
Correct the return-value check.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Message-Id: <20240129073921.446869-1-dmitry.osipenko@collabora.com>
Cc: qemu-stable@nongnu.org
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Jazz Jackrabbit has a very unusual VGA setup, where it uses odd/even mode
with 256-color graphics. Probably, it wants to use fast VRAM-to-VRAM
copies without having to store 4 copies of the sprites as needed in mode
X, one for each mod-4 alignment; odd/even mode simplifies the code a
lot if it's okay to place on a 160-pixels horizontal grid.
At the same time, because it wants to use double buffering (a la "mode X")
it uses byte mode, not word mode as is the case in text modes. In order
to implement the combination of odd/even mode (plane number comes from
bit 0 of the address) and byte mode (use all bytes of VRAM, whereas word
mode only uses bytes 0, 2, 4,... on each of the four planes), we need
to separate the effect on the plane number from the effect on the address.
Implementing the modes properly is a mess in QEMU, because it would
change the layout of VRAM and break migration. As an approximation,
shift right when the CPU accesses memory instead of shifting left when
the CRT controller reads it. A hack is needed in order to write font data
properly (see comment in the code), but it works well enough for the game.
Because doubleword and chain4 modes are now independent, chain4 does not
assert anymore that the address is in range. Instead it just returns
all ones and discards writes, like other modes.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Jazz Jackrabbit uses odd/even mode with 256-color graphics. This is
probably so that it can do very fast blitting with a decent resolution
(two pixels, compared to four pixels for "regular" mode X).
Accesses still use all planes (reads go to the latches and the game uses
read mode 1 so that the CPU always gets 0xFF; writes use the plane mask
register because the game sets bit 2 of the sequencer's memory mode
register). For this to work, QEMU needs to use the code for latched
memory accesses in odd/even mode. The only difference between odd/even
mode and "regular" planar mode is how the plane is computed in read mode
0, and how the planes are masked if the aforementioned bit 2 is reset.
It is almost enough to fix the game. You also need to honor byte/word
mode selection, which is done in the next patch.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The next patch will reuse latched memory access in text modes. Start with
a patch that moves the latched access code out of the "if".
Best reviewed with "git diff -b".
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This implements smooth scrolling, as used for example by Commander Keen
and Second Reality.
Unfortunately, this is not enough to avoid tearing in Commander Keen,
because sometimes the wrong start address is used for a frame.
On real EGA, the panning register is sampled on every line, while
the display start is latched for the next frame at the start of the
vertical retrace. On real VGA, the panning register is also latched,
but at the end of the vertical retrace. It looks like Keen exploits
this by only waiting for horizontal retrace when setting the display
start, but implementing it breaks the 256-color Keen games...
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This allows setting the start address to a high value, and reading the
bottom of the screen from the beginning of VRAM. Commander Keen 4
("Goodbye, Galaxy!") relies on this behavior.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The next patches will introduce more parameters that cause a full
refresh. Instead of adding arguments to get_offsets and lines to
update_basic_params, do everything through a struct.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The constant-expression bswap is provided by const_le32(), and GET_PLANE()
can also be implemented using cpu_to_le32(). Remove the custom macros in
vga.c.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The term "iothread lock" is obsolete. The APIs use Big QEMU Lock (BQL)
in their names. Update the code comments to use "BQL" instead of
"iothread lock".
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Paul Durrant <paul@xen.org>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Message-id: 20240102153529.486531-5-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The name "iothread" is overloaded. Use the term Big QEMU Lock (BQL)
instead, it is already widely used and unambiguous.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Paul Durrant <paul@xen.org>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-id: 20240102153529.486531-4-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This variable is about the host OS, not the target. It is used a lot
more since the Meson conversion, but the original sin dates back to 2003.
Time to fix it.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
