diff options
Diffstat (limited to 'src/mainboard/emulation/qemu-x86/fw_cfg.c')
-rw-r--r-- | src/mainboard/emulation/qemu-x86/fw_cfg.c | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/src/mainboard/emulation/qemu-x86/fw_cfg.c b/src/mainboard/emulation/qemu-x86/fw_cfg.c new file mode 100644 index 0000000000..5166f83092 --- /dev/null +++ b/src/mainboard/emulation/qemu-x86/fw_cfg.c @@ -0,0 +1,59 @@ +/* + * This file is part of the coreboot project. + * + * 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; version 2 of the License. + * + * 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, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <string.h> +#include <console/console.h> +#include <arch/io.h> + +#include "fw_cfg.h" +#include "fw_cfg_if.h" + +#define FW_CFG_PORT_CTL 0x0510 +#define FW_CFG_PORT_DATA 0x0511 + +static unsigned char fw_cfg_detected = 0xff; + +static int fw_cfg_present(void) +{ + static const char qsig[] = "QEMU"; + unsigned char sig[4]; + + if (fw_cfg_detected == 0xff) { + fw_cfg_get(FW_CFG_SIGNATURE, sig, sizeof(sig)); + fw_cfg_detected = (memcmp(sig, qsig, 4) == 0) ? 1 : 0; + printk(BIOS_INFO, "QEMU: firmware config interface %s\n", + fw_cfg_detected ? "detected" : "not found"); + } + return fw_cfg_detected; +} + +void fw_cfg_get(int entry, void *dst, int dstlen) +{ + outw(entry, FW_CFG_PORT_CTL); + insb(FW_CFG_PORT_DATA, dst, dstlen); +} + +int fw_cfg_max_cpus(void) +{ + unsigned short max_cpus; + + if (!fw_cfg_present()) + return -1; + + fw_cfg_get(FW_CFG_MAX_CPUS, &max_cpus, sizeof(max_cpus)); + return max_cpus; +} |