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1 #include <linux/console.h>
2 #include <linux/kernel.h>
3 #include <linux/init.h>
4 #include <linux/string.h>
5 #include <linux/screen_info.h>
6 #include <linux/usb/ch9.h>
7 #include <linux/pci_regs.h>
8 #include <linux/pci_ids.h>
9 #include <linux/errno.h>
10 #include <asm/io.h>
11 #include <asm/processor.h>
12 #include <asm/fcntl.h>
13 #include <asm/setup.h>
14 #include <xen/hvc-console.h>
15 #include <asm/pci-direct.h>
16 #include <asm/fixmap.h>
17 #include <asm/mrst.h>
18 #include <asm/pgtable.h>
19 #include <linux/usb/ehci_def.h>
20 
21 /* Simple VGA output */
22 #define VGABASE		(__ISA_IO_base + 0xb8000)
23 
24 static int max_ypos = 25, max_xpos = 80;
25 static int current_ypos = 25, current_xpos;
26 
early_vga_write(struct console * con,const char * str,unsigned n)27 static void early_vga_write(struct console *con, const char *str, unsigned n)
28 {
29 	char c;
30 	int  i, k, j;
31 
32 	while ((c = *str++) != '\0' && n-- > 0) {
33 		if (current_ypos >= max_ypos) {
34 			/* scroll 1 line up */
35 			for (k = 1, j = 0; k < max_ypos; k++, j++) {
36 				for (i = 0; i < max_xpos; i++) {
37 					writew(readw(VGABASE+2*(max_xpos*k+i)),
38 					       VGABASE + 2*(max_xpos*j + i));
39 				}
40 			}
41 			for (i = 0; i < max_xpos; i++)
42 				writew(0x720, VGABASE + 2*(max_xpos*j + i));
43 			current_ypos = max_ypos-1;
44 		}
45 #ifdef CONFIG_KGDB_KDB
46 		if (c == '\b') {
47 			if (current_xpos > 0)
48 				current_xpos--;
49 		} else if (c == '\r') {
50 			current_xpos = 0;
51 		} else
52 #endif
53 		if (c == '\n') {
54 			current_xpos = 0;
55 			current_ypos++;
56 		} else if (c != '\r')  {
57 			writew(((0x7 << 8) | (unsigned short) c),
58 			       VGABASE + 2*(max_xpos*current_ypos +
59 						current_xpos++));
60 			if (current_xpos >= max_xpos) {
61 				current_xpos = 0;
62 				current_ypos++;
63 			}
64 		}
65 	}
66 }
67 
68 static struct console early_vga_console = {
69 	.name =		"earlyvga",
70 	.write =	early_vga_write,
71 	.flags =	CON_PRINTBUFFER,
72 	.index =	-1,
73 };
74 
75 /* Serial functions loosely based on a similar package from Klaus P. Gerlicher */
76 
77 static int early_serial_base = 0x3f8;  /* ttyS0 */
78 
79 #define XMTRDY          0x20
80 
81 #define DLAB		0x80
82 
83 #define TXR             0       /*  Transmit register (WRITE) */
84 #define RXR             0       /*  Receive register  (READ)  */
85 #define IER             1       /*  Interrupt Enable          */
86 #define IIR             2       /*  Interrupt ID              */
87 #define FCR             2       /*  FIFO control              */
88 #define LCR             3       /*  Line control              */
89 #define MCR             4       /*  Modem control             */
90 #define LSR             5       /*  Line Status               */
91 #define MSR             6       /*  Modem Status              */
92 #define DLL             0       /*  Divisor Latch Low         */
93 #define DLH             1       /*  Divisor latch High        */
94 
early_serial_putc(unsigned char ch)95 static int early_serial_putc(unsigned char ch)
96 {
97 	unsigned timeout = 0xffff;
98 
99 	while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
100 		cpu_relax();
101 	outb(ch, early_serial_base + TXR);
102 	return timeout ? 0 : -1;
103 }
104 
early_serial_write(struct console * con,const char * s,unsigned n)105 static void early_serial_write(struct console *con, const char *s, unsigned n)
106 {
107 	while (*s && n-- > 0) {
108 		if (*s == '\n')
109 			early_serial_putc('\r');
110 		early_serial_putc(*s);
111 		s++;
112 	}
113 }
114 
115 #define DEFAULT_BAUD 9600
116 
early_serial_init(char * s)117 static __init void early_serial_init(char *s)
118 {
119 	unsigned char c;
120 	unsigned divisor;
121 	unsigned baud = DEFAULT_BAUD;
122 	char *e;
123 
124 	if (*s == ',')
125 		++s;
126 
127 	if (*s) {
128 		unsigned port;
129 		if (!strncmp(s, "0x", 2)) {
130 			early_serial_base = simple_strtoul(s, &e, 16);
131 		} else {
132 			static const int __initconst bases[] = { 0x3f8, 0x2f8 };
133 
134 			if (!strncmp(s, "ttyS", 4))
135 				s += 4;
136 			port = simple_strtoul(s, &e, 10);
137 			if (port > 1 || s == e)
138 				port = 0;
139 			early_serial_base = bases[port];
140 		}
141 		s += strcspn(s, ",");
142 		if (*s == ',')
143 			s++;
144 	}
145 
146 	outb(0x3, early_serial_base + LCR);	/* 8n1 */
147 	outb(0, early_serial_base + IER);	/* no interrupt */
148 	outb(0, early_serial_base + FCR);	/* no fifo */
149 	outb(0x3, early_serial_base + MCR);	/* DTR + RTS */
150 
151 	if (*s) {
152 		baud = simple_strtoul(s, &e, 0);
153 		if (baud == 0 || s == e)
154 			baud = DEFAULT_BAUD;
155 	}
156 
157 	divisor = 115200 / baud;
158 	c = inb(early_serial_base + LCR);
159 	outb(c | DLAB, early_serial_base + LCR);
160 	outb(divisor & 0xff, early_serial_base + DLL);
161 	outb((divisor >> 8) & 0xff, early_serial_base + DLH);
162 	outb(c & ~DLAB, early_serial_base + LCR);
163 }
164 
165 static struct console early_serial_console = {
166 	.name =		"earlyser",
167 	.write =	early_serial_write,
168 	.flags =	CON_PRINTBUFFER,
169 	.index =	-1,
170 };
171 
172 /* Direct interface for emergencies */
173 static struct console *early_console = &early_vga_console;
174 static int __initdata early_console_initialized;
175 
early_printk(const char * fmt,...)176 asmlinkage void early_printk(const char *fmt, ...)
177 {
178 	char buf[512];
179 	int n;
180 	va_list ap;
181 
182 	va_start(ap, fmt);
183 	n = vscnprintf(buf, sizeof(buf), fmt, ap);
184 	early_console->write(early_console, buf, n);
185 	va_end(ap);
186 }
187 
early_console_register(struct console * con,int keep_early)188 static inline void early_console_register(struct console *con, int keep_early)
189 {
190 	if (early_console->index != -1) {
191 		printk(KERN_CRIT "ERROR: earlyprintk= %s already used\n",
192 		       con->name);
193 		return;
194 	}
195 	early_console = con;
196 	if (keep_early)
197 		early_console->flags &= ~CON_BOOT;
198 	else
199 		early_console->flags |= CON_BOOT;
200 	register_console(early_console);
201 }
202 
setup_early_printk(char * buf)203 static int __init setup_early_printk(char *buf)
204 {
205 	int keep;
206 
207 	if (!buf)
208 		return 0;
209 
210 	if (early_console_initialized)
211 		return 0;
212 	early_console_initialized = 1;
213 
214 	keep = (strstr(buf, "keep") != NULL);
215 
216 	while (*buf != '\0') {
217 		if (!strncmp(buf, "serial", 6)) {
218 			buf += 6;
219 			early_serial_init(buf);
220 			early_console_register(&early_serial_console, keep);
221 			if (!strncmp(buf, ",ttyS", 5))
222 				buf += 5;
223 		}
224 		if (!strncmp(buf, "ttyS", 4)) {
225 			early_serial_init(buf + 4);
226 			early_console_register(&early_serial_console, keep);
227 		}
228 		if (!strncmp(buf, "vga", 3) &&
229 		    boot_params.screen_info.orig_video_isVGA == 1) {
230 			max_xpos = boot_params.screen_info.orig_video_cols;
231 			max_ypos = boot_params.screen_info.orig_video_lines;
232 			current_ypos = boot_params.screen_info.orig_y;
233 			early_console_register(&early_vga_console, keep);
234 		}
235 #ifdef CONFIG_EARLY_PRINTK_DBGP
236 		if (!strncmp(buf, "dbgp", 4) && !early_dbgp_init(buf + 4))
237 			early_console_register(&early_dbgp_console, keep);
238 #endif
239 #ifdef CONFIG_HVC_XEN
240 		if (!strncmp(buf, "xen", 3))
241 			early_console_register(&xenboot_console, keep);
242 #endif
243 #ifdef CONFIG_EARLY_PRINTK_INTEL_MID
244 		if (!strncmp(buf, "mrst", 4)) {
245 			mrst_early_console_init();
246 			early_console_register(&early_mrst_console, keep);
247 		}
248 
249 		if (!strncmp(buf, "hsu", 3)) {
250 			hsu_early_console_init(buf + 3);
251 			early_console_register(&early_hsu_console, keep);
252 		}
253 #endif
254 		buf++;
255 	}
256 	return 0;
257 }
258 
259 early_param("earlyprintk", setup_early_printk);
260