switch-coreboot/lib/uart8250.c
Uwe Hermann ff7df4f7ad Add cross compilation support and simplify the far to complex serial
code (This goes hand in hand, as some parts of serial were hardcoded
to one architecture until now)

* include/uart8250.h: add TTYSx defines that are used in
  multiple places. formerly part of arch/x86/serial.c.
  Drop init_uart8250 (unused)
* lib/uart8250.c: drop arch/x86/config.h usage
  Drop init_uart8250 (unused)
* arch/powerpc/Kconfig, arch/x86/Kconfig: add CONFIG_ARCH to
  contain the directory name under LinuxBIOSv3/arch/
* arch/x86/console.c: drop some dead code. Drop hardcoded config.h values.
  use generic uart8250.h header
* arch/x86/cachemain.c: Drop hardcoded config.h values. Still use hardcoded
  ROM size for now. (To be changed later)
* arch/x86/config.h: dropped, no longer needed
* arch/x86/serial.c: factor out generically used defines to uart8250.h
* Makefile: use mainboard architecture instead of target architecture to choose
  include path.
  Read .xcompile if available (configure replacement).
  Create build.h with compile time and version.
* util/xcompile/xcompile: new file. Search for supported cross compilers
  linkers, assemblers (and potentially supported compiler flags etc)
  This is a very slick configure replacement.
* util/dtc/Makefile: fix Makefile for cross compilation

Signed-off-by: Stefan Reinauer <stepan@coresystems.de>
Signed-off-by: Uwe Hermann <uwe@hermann-uwe.de>
Acked-by: Ronald G. Minnich <rminnich@gmail.com>



git-svn-id: svn://coreboot.org/repository/LinuxBIOSv3@190 f3766cd6-281f-0410-b1cd-43a5c92072e9
2007-03-05 21:14:21 +00:00

76 lines
1.7 KiB
C

/* Should support 8250, 16450, 16550, 16550A type uarts */
#include <arch/io.h>
#include <uart8250.h>
/* Data */
#define UART_RBR 0x00
#define UART_TBR 0x00
/* Control */
#define UART_IER 0x01
#define UART_IIR 0x02
#define UART_FCR 0x02
#define UART_LCR 0x03
#define UART_MCR 0x04
#define UART_DLL 0x00
#define UART_DLM 0x01
/* Status */
#define UART_LSR 0x05
#define UART_MSR 0x06
#define UART_SCR 0x07
static inline int uart8250_can_tx_byte(unsigned base_port)
{
return inb(base_port + UART_LSR) & 0x20;
}
static inline void uart8250_wait_to_tx_byte(unsigned base_port)
{
while(!uart8250_can_tx_byte(base_port))
;
}
static inline void uart8250_wait_until_sent(unsigned base_port)
{
while(!(inb(base_port + UART_LSR) & 0x40))
;
}
void uart8250_tx_byte(unsigned base_port, unsigned char data)
{
uart8250_wait_to_tx_byte(base_port);
outb(data, base_port + UART_TBR);
/* Make certain the data clears the fifos */
uart8250_wait_until_sent(base_port);
}
int uart8250_can_rx_byte(unsigned base_port)
{
return inb(base_port + UART_LSR) & 0x01;
}
unsigned char uart8250_rx_byte(unsigned base_port)
{
while(!uart8250_can_rx_byte(base_port))
;
return inb(base_port + UART_RBR);
}
/* Initialize a generic uart */
void uart8250_init(unsigned base_port, unsigned divisor, unsigned lcs)
{
lcs &= 0x7f;
/* disable interrupts */
outb(0x0, base_port + UART_IER);
/* enable fifo's */
outb(0x01, base_port + UART_FCR);
/* assert DTR and RTS so the other end is happy */
outb(0x03, base_port + UART_MCR);
/* Set Baud Rate Divisor to 12 ==> 115200 Baud */
outb(0x80 | lcs, base_port + UART_LCR);
outb(divisor & 0xFF, base_port + UART_DLL);
outb((divisor >> 8) & 0xFF, base_port + UART_DLM);
outb(lcs, base_port + UART_LCR);
}