diff options
Diffstat (limited to 'src/superio/fintek/f71869ad/early_serial.c')
-rw-r--r-- | src/superio/fintek/f71869ad/early_serial.c | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/src/superio/fintek/f71869ad/early_serial.c b/src/superio/fintek/f71869ad/early_serial.c new file mode 100644 index 0000000000..85184007ac --- /dev/null +++ b/src/superio/fintek/f71869ad/early_serial.c @@ -0,0 +1,68 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2014 Edward O'Callaghan <eocallaghan@alterapraxis.com> + * + * 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, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/* + * Pre-RAM driver for the Fintek F71869AD Super I/O chip. + * + * Derived from p.34 in vendor data-sheet: + * + * - default index port : 0x4E + * - default data port : 0x4F + * + * - enable configuration : 0x87 + * - disable configuration : 0xAA + * + */ + +#include <arch/io.h> +#include <device/pnp.h> +#include "f71869ad.h" + +/* + * Enable configuration: pass entry key '0x87' into index port dev. + */ +static void pnp_enter_conf_state(device_t dev) +{ + u16 port = dev >> 8; + outb(0x87, port); + outb(0x87, port); +} + +/* + * Disable configuration: pass exit key '0xAA' into index port dev. + */ +static void pnp_exit_conf_state(device_t dev) +{ + u16 port = dev >> 8; + outb(0xaa, port); +} + +/* + * Bring up early serial debugging output before the RAM is initialized. + */ +void f71869ad_enable_serial(device_t dev, u16 iobase) +{ + pnp_enter_conf_state(dev); + pnp_set_logical_device(dev); + pnp_set_enable(dev, 0); + pnp_set_iobase(dev, PNP_IDX_IO0, iobase); + pnp_set_enable(dev, 1); + pnp_exit_conf_state(dev); +} |