cachepc-qemu

Fork of AMDESE/qemu with changes for cachepc side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-qemu
Log | Files | Refs | Submodules | LICENSE | sfeed.txt

ramfb.c (3590B)

      1/*
      2 * early boot framebuffer in guest ram
      3 * configured using fw_cfg
      4 *
      5 * Copyright Red Hat, Inc. 2017
      6 *
      7 * Author:
      8 *     Gerd Hoffmann <kraxel@redhat.com>
      9 *
     10 * This work is licensed under the terms of the GNU GPL, version 2 or later.
     11 * See the COPYING file in the top-level directory.
     12 */
     13
     14#include "qemu/osdep.h"
     15#include "qapi/error.h"
     16#include "hw/loader.h"
     17#include "hw/display/ramfb.h"
     18#include "hw/display/bochs-vbe.h" /* for limits */
     19#include "ui/console.h"
     20#include "sysemu/reset.h"
     21
     22struct QEMU_PACKED RAMFBCfg {
     23    uint64_t addr;
     24    uint32_t fourcc;
     25    uint32_t flags;
     26    uint32_t width;
     27    uint32_t height;
     28    uint32_t stride;
     29};
     30
     31struct RAMFBState {
     32    DisplaySurface *ds;
     33    uint32_t width, height;
     34    struct RAMFBCfg cfg;
     35};
     36
     37static void ramfb_unmap_display_surface(pixman_image_t *image, void *unused)
     38{
     39    void *data = pixman_image_get_data(image);
     40    uint32_t size = pixman_image_get_stride(image) *
     41        pixman_image_get_height(image);
     42    cpu_physical_memory_unmap(data, size, 0, 0);
     43}
     44
     45static DisplaySurface *ramfb_create_display_surface(int width, int height,
     46                                                    pixman_format_code_t format,
     47                                                    hwaddr stride, hwaddr addr)
     48{
     49    DisplaySurface *surface;
     50    hwaddr size, mapsize, linesize;
     51    void *data;
     52
     53    if (width < 16 || width > VBE_DISPI_MAX_XRES ||
     54        height < 16 || height > VBE_DISPI_MAX_YRES ||
     55        format == 0 /* unknown format */)
     56        return NULL;
     57
     58    linesize = width * PIXMAN_FORMAT_BPP(format) / 8;
     59    if (stride == 0) {
     60        stride = linesize;
     61    }
     62
     63    mapsize = size = stride * (height - 1) + linesize;
     64    data = cpu_physical_memory_map(addr, &mapsize, false);
     65    if (size != mapsize) {
     66        cpu_physical_memory_unmap(data, mapsize, 0, 0);
     67        return NULL;
     68    }
     69
     70    surface = qemu_create_displaysurface_from(width, height,
     71                                              format, stride, data);
     72    pixman_image_set_destroy_function(surface->image,
     73                                      ramfb_unmap_display_surface, NULL);
     74
     75    return surface;
     76}
     77
     78static void ramfb_fw_cfg_write(void *dev, off_t offset, size_t len)
     79{
     80    RAMFBState *s = dev;
     81    DisplaySurface *surface;
     82    uint32_t fourcc, format, width, height;
     83    hwaddr stride, addr;
     84
     85    width  = be32_to_cpu(s->cfg.width);
     86    height = be32_to_cpu(s->cfg.height);
     87    stride = be32_to_cpu(s->cfg.stride);
     88    fourcc = be32_to_cpu(s->cfg.fourcc);
     89    addr   = be64_to_cpu(s->cfg.addr);
     90    format = qemu_drm_format_to_pixman(fourcc);
     91
     92    surface = ramfb_create_display_surface(width, height,
     93                                           format, stride, addr);
     94    if (!surface) {
     95        return;
     96    }
     97
     98    s->width = width;
     99    s->height = height;
    100    s->ds = surface;
    101}
    102
    103void ramfb_display_update(QemuConsole *con, RAMFBState *s)
    104{
    105    if (!s->width || !s->height) {
    106        return;
    107    }
    108
    109    if (s->ds) {
    110        dpy_gfx_replace_surface(con, s->ds);
    111        s->ds = NULL;
    112    }
    113
    114    /* simple full screen update */
    115    dpy_gfx_update_full(con);
    116}
    117
    118RAMFBState *ramfb_setup(Error **errp)
    119{
    120    FWCfgState *fw_cfg = fw_cfg_find();
    121    RAMFBState *s;
    122
    123    if (!fw_cfg || !fw_cfg->dma_enabled) {
    124        error_setg(errp, "ramfb device requires fw_cfg with DMA");
    125        return NULL;
    126    }
    127
    128    s = g_new0(RAMFBState, 1);
    129
    130    rom_add_vga("vgabios-ramfb.bin");
    131    fw_cfg_add_file_callback(fw_cfg, "etc/ramfb",
    132                             NULL, ramfb_fw_cfg_write, s,
    133                             &s->cfg, sizeof(s->cfg), false);
    134    return s;
    135}