diff options
Diffstat (limited to 'src/northbridge/via/vx800/early_serial.c')
-rw-r--r-- | src/northbridge/via/vx800/early_serial.c | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/src/northbridge/via/vx800/early_serial.c b/src/northbridge/via/vx800/early_serial.c new file mode 100644 index 0000000000..f46341ff15 --- /dev/null +++ b/src/northbridge/via/vx800/early_serial.c @@ -0,0 +1,101 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2009 One Laptop per Child, Association, Inc. + * + * 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 +*/ + +/* + * Enable the serial devices on the VIA + */ +#include <arch/romcc_io.h> + +/* The base address is 0x15c, 0x2e, depending on config bytes */ + +#define SIO_BASE 0x3f0 +#define SIO_DATA SIO_BASE+1 + +static void vx800_writepnpaddr(uint8_t val) +{ + outb(val, 0x2e); + outb(val, 0xeb); +} + +static void vx800_writepnpdata(uint8_t val) +{ + outb(val, 0x2f); + outb(val, 0xeb); +} + +static void vx800_writesiobyte(uint16_t reg, uint8_t val) +{ + outb(val, reg); +} + +static void vx800_writesioword(uint16_t reg, uint16_t val) +{ + outw(val, reg); +} + +/* regs we use: 85, and the southbridge devfn is defined by the + mainboard + */ + +void enable_vx800_serial(void) +{ + outb(6, 0x80); + outb(0x03, 0x22); + + //pci_write_config8(PCI_DEV(0,17,0),0xb4,0x7e); + //pci_write_config8(PCI_DEV(0,17,0),0xb0,0x10); + + // turn on pnp + vx800_writepnpaddr(0x87); + vx800_writepnpaddr(0x87); + // now go ahead and set up com1. + // set address + vx800_writepnpaddr(0x7); + vx800_writepnpdata(0x2); + // enable serial out + vx800_writepnpaddr(0x30); + vx800_writepnpdata(0x1); + // serial port 1 base address (FEh) + vx800_writepnpaddr(0x60); + vx800_writepnpdata(0xfe); + // serial port 1 IRQ (04h) + vx800_writepnpaddr(0x70); + vx800_writepnpdata(0x4); + // serial port 1 control + vx800_writepnpaddr(0xf0); + vx800_writepnpdata(0x2); + // turn of pnp + vx800_writepnpaddr(0xaa); + + // set up reg to set baud rate. + vx800_writesiobyte(0x3fb, 0x80); + // Set 115 kb + vx800_writesioword(0x3f8, 1); + // Set 9.6 kb + // WRITESIOWORD(0x3f8, 12) + // now set no parity, one stop, 8 bits + vx800_writesiobyte(0x3fb, 3); + // now turn on RTS, DRT + vx800_writesiobyte(0x3fc, 3); + // Enable interrupts + vx800_writesiobyte(0x3f9, 0xf); + // should be done. Dump a char for fun. + vx800_writesiobyte(0x3f8, 48); + outb(7, 0x80); +} |