/*
* Common Option ROM Functions for fw_cfg
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*
* Copyright (c) 2015-2019 Red Hat Inc.
* Authors:
* Marc Marí <marc.mari.barcelo@gmail.com>
* Richard W.M. Jones <rjones@redhat.com>
* Stefano Garzarella <sgarzare@redhat.com>
*/
#ifndef OPTROM_FW_CFG_H
#define OPTROM_FW_CFG_H
#include "../../include/standard-headers/linux/qemu_fw_cfg.h"
#define BIOS_CFG_IOPORT_CFG 0x510
#define BIOS_CFG_IOPORT_DATA 0x511
#define BIOS_CFG_DMA_ADDR_HIGH 0x514
#define BIOS_CFG_DMA_ADDR_LOW 0x518
static __attribute__((unused))
void bios_cfg_select(uint16_t key)
{
outw(key, BIOS_CFG_IOPORT_CFG);
}
static __attribute__((unused))
void bios_cfg_read_entry_io(void *buf, uint16_t entry, uint32_t len)
{
bios_cfg_select(entry);
insb(BIOS_CFG_IOPORT_DATA, buf, len);
}
/*
* clang is happy to inline this function, and bloats the
* ROM.
*/
static __attribute__((__noinline__)) __attribute__((unused))
void bios_cfg_read_entry_dma(void *buf, uint16_t entry, uint32_t len)
{
struct fw_cfg_dma_access access;
uint32_t control = (entry << 16) | FW_CFG_DMA_CTL_SELECT
| FW_CFG_DMA_CTL_READ;
access.address = cpu_to_be64((uint64_t)(uint32_t)buf);
access.length = cpu_to_be32(len);
access.control = cpu_to_be32(control);
barrier();
outl(cpu_to_be32((uint32_t)&access), BIOS_CFG_DMA_ADDR_LOW);
while (be32_to_cpu(access.control) & ~FW_CFG_DMA_CTL_ERROR) {
barrier();
}
}
static __attribute__((unused))
void bios_cfg_read_entry(void *buf, uint16_t entry, uint32_t len,
uint32_t version)
{
if (version & FW_CFG_VERSION_DMA) {
bios_cfg_read_entry_dma(buf, entry, len);
} else {
bios_cfg_read_entry_io(buf, entry, len);
}
}
static __attribute__((unused))
uint32_t bios_cfg_version(void)
{
uint32_t version;
bios_cfg_read_entry_io(&version, FW_CFG_ID, sizeof(version));
return version;
}
#endif /* OPTROM_FW_CFG_H */
