1 #include <linux/console.h>
2 #include <linux/kernel.h>
3 #include <linux/init.h>
4 #include <linux/string.h>
7 #include <asm/processor.h>
10 /* Simple VGA output */
13 #include <asm/setup.h>
14 #define VGABASE (__ISA_IO_base + 0xb8000)
16 #include <asm/bootsetup.h>
17 #define VGABASE ((void __iomem *)0xffffffff800b8000UL)
20 #define MAX_YPOS max_ypos
21 #define MAX_XPOS max_xpos
23 static int max_ypos
= 25, max_xpos
= 80;
24 static int current_ypos
= 1, current_xpos
= 0;
26 static void early_vga_write(struct console
*con
, const char *str
, unsigned n
)
31 while ((c
= *str
++) != '\0' && n
-- > 0) {
32 if (current_ypos
>= MAX_YPOS
) {
33 /* scroll 1 line up */
34 for (k
= 1, j
= 0; k
< MAX_YPOS
; k
++, j
++) {
35 for (i
= 0; i
< MAX_XPOS
; i
++) {
36 writew(readw(VGABASE
+ 2*(MAX_XPOS
*k
+ i
)),
37 VGABASE
+ 2*(MAX_XPOS
*j
+ i
));
40 for (i
= 0; i
< MAX_XPOS
; i
++)
41 writew(0x720, VGABASE
+ 2*(MAX_XPOS
*j
+ i
));
42 current_ypos
= MAX_YPOS
-1;
47 } else if (c
!= '\r') {
48 writew(((0x7 << 8) | (unsigned short) c
),
49 VGABASE
+ 2*(MAX_XPOS
*current_ypos
+
51 if (current_xpos
>= MAX_XPOS
) {
59 static struct console early_vga_console
= {
61 .write
= early_vga_write
,
62 .flags
= CON_PRINTBUFFER
,
66 /* Serial functions loosely based on a similar package from Klaus P. Gerlicher */
68 static int early_serial_base
= 0x3f8; /* ttyS0 */
74 #define TXR 0 /* Transmit register (WRITE) */
75 #define RXR 0 /* Receive register (READ) */
76 #define IER 1 /* Interrupt Enable */
77 #define IIR 2 /* Interrupt ID */
78 #define FCR 2 /* FIFO control */
79 #define LCR 3 /* Line control */
80 #define MCR 4 /* Modem control */
81 #define LSR 5 /* Line Status */
82 #define MSR 6 /* Modem Status */
83 #define DLL 0 /* Divisor Latch Low */
84 #define DLH 1 /* Divisor latch High */
86 static int early_serial_putc(unsigned char ch
)
88 unsigned timeout
= 0xffff;
89 while ((inb(early_serial_base
+ LSR
) & XMTRDY
) == 0 && --timeout
)
91 outb(ch
, early_serial_base
+ TXR
);
92 return timeout
? 0 : -1;
95 static void early_serial_write(struct console
*con
, const char *s
, unsigned n
)
97 while (*s
&& n
-- > 0) {
98 early_serial_putc(*s
);
100 early_serial_putc('\r');
105 #define DEFAULT_BAUD 9600
107 static __init
void early_serial_init(char *s
)
111 unsigned baud
= DEFAULT_BAUD
;
119 if (!strncmp(s
,"0x",2)) {
120 early_serial_base
= simple_strtoul(s
, &e
, 16);
122 static int bases
[] = { 0x3f8, 0x2f8 };
124 if (!strncmp(s
,"ttyS",4))
126 port
= simple_strtoul(s
, &e
, 10);
127 if (port
> 1 || s
== e
)
129 early_serial_base
= bases
[port
];
131 s
+= strcspn(s
, ",");
136 outb(0x3, early_serial_base
+ LCR
); /* 8n1 */
137 outb(0, early_serial_base
+ IER
); /* no interrupt */
138 outb(0, early_serial_base
+ FCR
); /* no fifo */
139 outb(0x3, early_serial_base
+ MCR
); /* DTR + RTS */
142 baud
= simple_strtoul(s
, &e
, 0);
143 if (baud
== 0 || s
== e
)
147 divisor
= 115200 / baud
;
148 c
= inb(early_serial_base
+ LCR
);
149 outb(c
| DLAB
, early_serial_base
+ LCR
);
150 outb(divisor
& 0xff, early_serial_base
+ DLL
);
151 outb((divisor
>> 8) & 0xff, early_serial_base
+ DLH
);
152 outb(c
& ~DLAB
, early_serial_base
+ LCR
);
155 static struct console early_serial_console
= {
157 .write
= early_serial_write
,
158 .flags
= CON_PRINTBUFFER
,
162 /* Console interface to a host file on AMD's SimNow! */
164 static int simnow_fd
;
173 static noinline
long simnow(long cmd
, long a
, long b
, long c
)
176 asm volatile("cpuid" :
178 "b" (a
), "c" (b
), "d" (c
), "0" (MAGIC1
), "D" (cmd
+ MAGIC2
));
182 void __init
simnow_init(char *str
)
188 simnow_fd
= simnow(XOPEN
, (unsigned long)fn
, O_WRONLY
|O_APPEND
|O_CREAT
, 0644);
191 static void simnow_write(struct console
*con
, const char *s
, unsigned n
)
193 simnow(XWRITE
, simnow_fd
, (unsigned long)s
, n
);
196 static struct console simnow_console
= {
198 .write
= simnow_write
,
199 .flags
= CON_PRINTBUFFER
,
203 /* Direct interface for emergencies */
204 struct console
*early_console
= &early_vga_console
;
205 static int early_console_initialized
= 0;
207 void early_printk(const char *fmt
, ...)
214 n
= vscnprintf(buf
,512,fmt
,ap
);
215 early_console
->write(early_console
,buf
,n
);
219 static int keep_early
;
221 int __init
setup_early_printk(char *opt
)
226 if (early_console_initialized
)
229 opt
= strchr(opt
, '=') + 1;
231 strlcpy(buf
,opt
,sizeof(buf
));
232 space
= strchr(buf
, ' ');
236 if (strstr(buf
,"keep"))
239 if (!strncmp(buf
, "serial", 6)) {
240 early_serial_init(buf
+ 6);
241 early_console
= &early_serial_console
;
242 } else if (!strncmp(buf
, "ttyS", 4)) {
243 early_serial_init(buf
);
244 early_console
= &early_serial_console
;
245 } else if (!strncmp(buf
, "vga", 3)
246 && SCREEN_INFO
.orig_video_isVGA
== 1) {
247 max_xpos
= SCREEN_INFO
.orig_video_cols
;
248 max_ypos
= SCREEN_INFO
.orig_video_lines
;
249 early_console
= &early_vga_console
;
250 } else if (!strncmp(buf
, "simnow", 6)) {
251 simnow_init(buf
+ 6);
252 early_console
= &simnow_console
;
255 early_console_initialized
= 1;
256 register_console(early_console
);
260 void __init
disable_early_printk(void)
262 if (!early_console_initialized
|| !early_console
)
265 printk("disabling early console\n");
266 unregister_console(early_console
);
267 early_console_initialized
= 0;
269 printk("keeping early console\n");
273 __setup("earlyprintk=", setup_early_printk
);