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

i2c-ddc.c (3330B)

      1/* A simple I2C slave for returning monitor EDID data via DDC.
      2 *
      3 * Copyright (c) 2011 Linaro Limited
      4 * Written by Peter Maydell
      5 *
      6 *  This program is free software; you can redistribute it and/or modify
      7 *  it under the terms of the GNU General Public License version 2 as
      8 *  published by the Free Software Foundation.
      9 *
     10 *  This program is distributed in the hope that it will be useful,
     11 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
     12 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     13 *  GNU General Public License for more details.
     14 *
     15 *  You should have received a copy of the GNU General Public License along
     16 *  with this program; if not, see <http://www.gnu.org/licenses/>.
     17 */
     18
     19#include "qemu/osdep.h"
     20#include "qemu/log.h"
     21#include "qemu/module.h"
     22#include "hw/i2c/i2c.h"
     23#include "hw/qdev-properties.h"
     24#include "migration/vmstate.h"
     25#include "hw/display/i2c-ddc.h"
     26
     27#ifndef DEBUG_I2CDDC
     28#define DEBUG_I2CDDC 0
     29#endif
     30
     31#define DPRINTF(fmt, ...) do {                                                 \
     32    if (DEBUG_I2CDDC) {                                                        \
     33        qemu_log("i2c-ddc: " fmt , ## __VA_ARGS__);                            \
     34    }                                                                          \
     35} while (0)
     36
     37static void i2c_ddc_reset(DeviceState *ds)
     38{
     39    I2CDDCState *s = I2CDDC(ds);
     40
     41    s->firstbyte = false;
     42    s->reg = 0;
     43}
     44
     45static int i2c_ddc_event(I2CSlave *i2c, enum i2c_event event)
     46{
     47    I2CDDCState *s = I2CDDC(i2c);
     48
     49    if (event == I2C_START_SEND) {
     50        s->firstbyte = true;
     51    }
     52
     53    return 0;
     54}
     55
     56static uint8_t i2c_ddc_rx(I2CSlave *i2c)
     57{
     58    I2CDDCState *s = I2CDDC(i2c);
     59
     60    int value;
     61    value = s->edid_blob[s->reg % sizeof(s->edid_blob)];
     62    s->reg++;
     63    return value;
     64}
     65
     66static int i2c_ddc_tx(I2CSlave *i2c, uint8_t data)
     67{
     68    I2CDDCState *s = I2CDDC(i2c);
     69    if (s->firstbyte) {
     70        s->reg = data;
     71        s->firstbyte = false;
     72        DPRINTF("[EDID] Written new pointer: %u\n", data);
     73        return 0;
     74    }
     75
     76    /* Ignore all writes */
     77    s->reg++;
     78    return 0;
     79}
     80
     81static void i2c_ddc_init(Object *obj)
     82{
     83    I2CDDCState *s = I2CDDC(obj);
     84
     85    qemu_edid_generate(s->edid_blob, sizeof(s->edid_blob), &s->edid_info);
     86}
     87
     88static const VMStateDescription vmstate_i2c_ddc = {
     89    .name = TYPE_I2CDDC,
     90    .version_id = 1,
     91    .fields = (VMStateField[]) {
     92        VMSTATE_BOOL(firstbyte, I2CDDCState),
     93        VMSTATE_UINT8(reg, I2CDDCState),
     94        VMSTATE_END_OF_LIST()
     95    }
     96};
     97
     98static Property i2c_ddc_properties[] = {
     99    DEFINE_EDID_PROPERTIES(I2CDDCState, edid_info),
    100    DEFINE_PROP_END_OF_LIST(),
    101};
    102
    103static void i2c_ddc_class_init(ObjectClass *oc, void *data)
    104{
    105    DeviceClass *dc = DEVICE_CLASS(oc);
    106    I2CSlaveClass *isc = I2C_SLAVE_CLASS(oc);
    107
    108    dc->reset = i2c_ddc_reset;
    109    dc->vmsd = &vmstate_i2c_ddc;
    110    device_class_set_props(dc, i2c_ddc_properties);
    111    isc->event = i2c_ddc_event;
    112    isc->recv = i2c_ddc_rx;
    113    isc->send = i2c_ddc_tx;
    114}
    115
    116static TypeInfo i2c_ddc_info = {
    117    .name = TYPE_I2CDDC,
    118    .parent = TYPE_I2C_SLAVE,
    119    .instance_size = sizeof(I2CDDCState),
    120    .instance_init = i2c_ddc_init,
    121    .class_init = i2c_ddc_class_init
    122};
    123
    124static void ddc_register_devices(void)
    125{
    126    type_register_static(&i2c_ddc_info);
    127}
    128
    129type_init(ddc_register_devices);