linux/arch/mips/pmc-sierra/yosemite/py-console.c

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/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2001, 2002, 2004 Ralf Baechle
*/
#include <linux/init.h>
#include <linux/console.h>
#include <linux/kdev_t.h>
#include <linux/major.h>
#include <linux/termios.h>
#include <linux/sched.h>
#include <linux/tty.h>
#include <linux/serial.h>
#include <linux/serial_core.h>
#include <asm/serial.h>
#include <asm/io.h>
/* SUPERIO uart register map */
struct yo_uartregs {
union {
volatile u8 rbr; /* read only, DLAB == 0 */
volatile u8 thr; /* write only, DLAB == 0 */
volatile u8 dll; /* DLAB == 1 */
} u1;
union {
volatile u8 ier; /* DLAB == 0 */
volatile u8 dlm; /* DLAB == 1 */
} u2;
union {
volatile u8 iir; /* read only */
volatile u8 fcr; /* write only */
} u3;
volatile u8 iu_lcr;
volatile u8 iu_mcr;
volatile u8 iu_lsr;
volatile u8 iu_msr;
volatile u8 iu_scr;
} yo_uregs_t;
#define iu_rbr u1.rbr
#define iu_thr u1.thr
#define iu_dll u1.dll
#define iu_ier u2.ier
#define iu_dlm u2.dlm
#define iu_iir u3.iir
#define iu_fcr u3.fcr
#define ssnop() __asm__ __volatile__("sll $0, $0, 1\n");
#define ssnop_4() do { ssnop(); ssnop(); ssnop(); ssnop(); } while (0)
#define IO_BASE_64 0x9000000000000000ULL
static unsigned char readb_outer_space(unsigned long long phys)
{
unsigned long long vaddr = IO_BASE_64 | phys;
unsigned char res;
unsigned int sr;
sr = read_c0_status();
write_c0_status((sr | ST0_KX) & ~ ST0_IE);
ssnop_4();
__asm__ __volatile__ (
" .set mips3 \n"
" ld %0, %1 \n"
" lbu %0, (%0) \n"
" .set mips0 \n"
: "=r" (res)
: "m" (vaddr));
write_c0_status(sr);
ssnop_4();
return res;
}
static void writeb_outer_space(unsigned long long phys, unsigned char c)
{
unsigned long long vaddr = IO_BASE_64 | phys;
unsigned long tmp;
unsigned int sr;
sr = read_c0_status();
write_c0_status((sr | ST0_KX) & ~ ST0_IE);
ssnop_4();
__asm__ __volatile__ (
" .set mips3 \n"
" ld %0, %1 \n"
" sb %2, (%0) \n"
" .set mips0 \n"
: "=&r" (tmp)
: "m" (vaddr), "r" (c));
write_c0_status(sr);
ssnop_4();
}
void prom_putchar(char c)
{
unsigned long lsr = 0xfd000008ULL + offsetof(struct yo_uartregs, iu_lsr);
unsigned long thr = 0xfd000008ULL + offsetof(struct yo_uartregs, iu_thr);
while ((readb_outer_space(lsr) & 0x20) == 0);
writeb_outer_space(thr, c);
}