qemu/hw/display/ramfb.c

136 lines
3.5 KiB
C

/*
* early boot framebuffer in guest ram
* configured using fw_cfg
*
* Copyright Red Hat, Inc. 2017
*
* Author:
* Gerd Hoffmann <kraxel@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "hw/loader.h"
#include "hw/display/ramfb.h"
#include "hw/display/bochs-vbe.h" /* for limits */
#include "ui/console.h"
#include "sysemu/reset.h"
struct QEMU_PACKED RAMFBCfg {
uint64_t addr;
uint32_t fourcc;
uint32_t flags;
uint32_t width;
uint32_t height;
uint32_t stride;
};
struct RAMFBState {
DisplaySurface *ds;
uint32_t width, height;
struct RAMFBCfg cfg;
};
static void ramfb_unmap_display_surface(pixman_image_t *image, void *unused)
{
void *data = pixman_image_get_data(image);
uint32_t size = pixman_image_get_stride(image) *
pixman_image_get_height(image);
cpu_physical_memory_unmap(data, size, 0, 0);
}
static DisplaySurface *ramfb_create_display_surface(int width, int height,
pixman_format_code_t format,
hwaddr stride, hwaddr addr)
{
DisplaySurface *surface;
hwaddr size, mapsize, linesize;
void *data;
if (width < 16 || width > VBE_DISPI_MAX_XRES ||
height < 16 || height > VBE_DISPI_MAX_YRES ||
format == 0 /* unknown format */)
return NULL;
linesize = width * PIXMAN_FORMAT_BPP(format) / 8;
if (stride == 0) {
stride = linesize;
}
mapsize = size = stride * (height - 1) + linesize;
data = cpu_physical_memory_map(addr, &mapsize, false);
if (size != mapsize) {
cpu_physical_memory_unmap(data, mapsize, 0, 0);
return NULL;
}
surface = qemu_create_displaysurface_from(width, height,
format, stride, data);
pixman_image_set_destroy_function(surface->image,
ramfb_unmap_display_surface, NULL);
return surface;
}
static void ramfb_fw_cfg_write(void *dev, off_t offset, size_t len)
{
RAMFBState *s = dev;
DisplaySurface *surface;
uint32_t fourcc, format, width, height;
hwaddr stride, addr;
width = be32_to_cpu(s->cfg.width);
height = be32_to_cpu(s->cfg.height);
stride = be32_to_cpu(s->cfg.stride);
fourcc = be32_to_cpu(s->cfg.fourcc);
addr = be64_to_cpu(s->cfg.addr);
format = qemu_drm_format_to_pixman(fourcc);
surface = ramfb_create_display_surface(width, height,
format, stride, addr);
if (!surface) {
return;
}
s->width = width;
s->height = height;
s->ds = surface;
}
void ramfb_display_update(QemuConsole *con, RAMFBState *s)
{
if (!s->width || !s->height) {
return;
}
if (s->ds) {
dpy_gfx_replace_surface(con, s->ds);
s->ds = NULL;
}
/* simple full screen update */
dpy_gfx_update_full(con);
}
RAMFBState *ramfb_setup(Error **errp)
{
FWCfgState *fw_cfg = fw_cfg_find();
RAMFBState *s;
if (!fw_cfg || !fw_cfg->dma_enabled) {
error_setg(errp, "ramfb device requires fw_cfg with DMA");
return NULL;
}
s = g_new0(RAMFBState, 1);
rom_add_vga("vgabios-ramfb.bin");
fw_cfg_add_file_callback(fw_cfg, "etc/ramfb",
NULL, ramfb_fw_cfg_write, s,
&s->cfg, sizeof(s->cfg), false);
return s;
}