acrn-hypervisor/devicemodel/hw/platform/cmos_io.c

104 lines
2.9 KiB
C

/*************************************************************************
* INTEL CONFIDENTIAL
* Copyright 2018 Intel Corporation
*
* The source code contained or described herein and all documents related to
* the source code ("Material") are owned by Intel Corporation or its
* suppliers or licensors. Title to the Material remains with Intel
* Corporation or its suppliers and licensors. The Material contains trade
* secrets and proprietary and confidential information of Intel or its
* suppliers and licensors. The Material is protected by worldwide copyright
* and trade secret laws and treaty provisions. No part of the Material may
* be used, copied, reproduced, modified, published, uploaded, posted,
* transmitted, distributed, or disclosed in any way without Intel's prior
* express written permission.
*
* No license under any patent, copyright, trade secret or other
* intellectual property right is granted to or conferred upon you by
* disclosure or delivery of the Materials, either expressly, by
* implication, inducement, estoppel or otherwise. Any license under such
* intellectual property rights must be express and approved by Intel in
* writing.
*************************************************************************/
/* cmos io device is used for android device reboot to bootloader or
* recovery or normal boot usage
*/
#include <stdio.h>
#include <assert.h>
#include "inout.h"
#define CMOS_ADDR 0x74
#define CMOS_DATA 0x75
#define CMOS_BUF_SIZE 256
#define CMOS_NAME "cmos_io"
/* #define CMOS_DEBUG */
#ifdef CMOS_DEBUG
static FILE * dbg_file;
#define DPRINTF(format, args...) \
do { fprintf(dbg_file, format, args); fflush(dbg_file); } while (0)
#else
#define DPRINTF(format, arg...)
#endif
/* cmos buffer used to store write/read contents,
* and it should not be cleared when reboot
*/
static uint8_t cmos_buffer[CMOS_BUF_SIZE];
static int
cmos_io_handler(struct vmctx *ctx, int vcpu, int in, int port, int bytes,
uint32_t *eax, void *arg)
{
static int buf_offset;
static int next_ops; /* 0 for addr, 1 for data, in pair (addr,data)*/
assert(port == CMOS_ADDR || port == CMOS_DATA);
assert(bytes == 1);
#ifdef CMOS_DEBUG
if (!dbg_file)
dbg_file = fopen("/tmp/cmos_log", "a+");
#endif
DPRINTF("%s port =0x%x, in=%d, size=%d, val=0x%x, ops=%d\n",
__func__, port, in, bytes, (uint8_t)*eax, next_ops);
if (port == CMOS_ADDR) {
/* if port is addr, ops should be 0 */
assert(next_ops == 0 && !in);
if (next_ops != 0) {
next_ops = 0;
return -1;
}
buf_offset = (uint8_t)(*eax);
next_ops = 1;
} else if (port == CMOS_DATA) {
assert(next_ops == 1);
if (next_ops != 1) {
next_ops = 0;
return -1;
}
if (in)
*eax = cmos_buffer[buf_offset];
else
cmos_buffer[buf_offset] = (uint8_t)*eax;
next_ops = 0;
}
return 0;
}
INOUT_PORT(cmos_io, CMOS_ADDR, IOPORT_F_INOUT, cmos_io_handler);
INOUT_PORT(cmos_io, CMOS_DATA, IOPORT_F_INOUT, cmos_io_handler);