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/* SPDX-License-Identifier: GPL-2.0-only */
/* This file is part of the coreboot project. */
#include <stdint.h>
#include <arch/io.h>
#include "sio1007.h"
void sio1007_setreg(u16 lpc_port, u8 reg, u8 value, u8 mask)
{
u8 reg_value;
outb(reg, lpc_port);
reg_value = inb(lpc_port + 1);
reg_value &= ~mask;
reg_value |= (value & mask);
outb(reg_value, lpc_port + 1);
}
int sio1007_enable_uart_at(u16 port)
{
/* Enable config mode. */
outb(0x55, port);
if (inb(port) != 0x55)
return 0; /* There is no LPC device at this address. */
/* Registers 12 and 13 hold config address, look for a match. */
outb(0x12, port);
if (inb(port + 1) != (port & 0xff))
return 0;
outb(0x13, port);
if (inb(port + 1) != (port >> 8))
return 0;
/* This must be the sio1007, enable the UART. */
/* turn on power */
sio1007_setreg(port, 0x2, 1 << 3, 1 << 3);
/* enable high speed */
sio1007_setreg(port, 0xc, 1 << 6, 1 << 6);
/* set the base address */
sio1007_setreg(port, 0x24, CONFIG_TTYS0_BASE >> 2, 0xff);
/* Disable config mode. */
outb(0xaa, port);
return 1;
}
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