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

105 lines
2.3 KiB
C

/*
* Copyright (C) 2019 Intel Corporation. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
/* cmos io device
* - nvram 0x10 ~ 0x1F is used for android device reboot to bootloader or
* recovery or normal boot usage
* - vrpmb 0x20 ~ 0x9F is used to store vrpmb for guest, read to clear
*/
#include <stdio.h>
#include <stdbool.h>
#include "inout.h"
#include "vmmapi.h"
#include "vrpmb.h"
#include "log.h"
#define CMOS_ADDR 0x74
#define CMOS_DATA 0x75
#define CMOS_NAME "cmos_io"
#define CMOS_VRPMB_START 0x20
#define CMOS_VRPMB_END 0x9F
/* cmos buffer used to store write/read contents,
* and it should not be cleared when reboot
*/
static uint8_t cmos_buffer[CMOS_BUF_SIZE];
/* #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
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)*/
#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 */
if (next_ops != 0) {
next_ops = 0;
return -1;
}
buf_offset = (uint8_t)(*eax);
next_ops = 1;
} else if (port == CMOS_DATA) {
if (next_ops != 1) {
next_ops = 0;
return -1;
}
if (in) {
*eax = cmos_buffer[buf_offset];
/* read to clear for Key range */
if ((buf_offset >= CMOS_VRPMB_START) &&
(buf_offset <= CMOS_VRPMB_END))
cmos_buffer[buf_offset] = 0;
}
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);
int init_cmos_vrpmb(struct vmctx *ctx)
{
uint8_t *vrpmb_buffer = &cmos_buffer[CMOS_VRPMB_START];
/* get vrpmb key, and store it to cmos buffer */
if (!get_vrpmb_key(vrpmb_buffer, RPMB_KEY_LEN)) {
pr_err("SW_LOAD: failed to get vrpmb key\n");
return -1;
}
return 0;
}