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x86: earlyprintk: Fix regression to handle serial,ttySn as 1 arg
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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/pgtable.h>
18 #include <linux/usb/ehci_def.h>
19
20 /* Simple VGA output */
21 #define VGABASE (__ISA_IO_base + 0xb8000)
22
23 static int max_ypos = 25, max_xpos = 80;
24 static int current_ypos = 25, current_xpos;
25
26 static void early_vga_write(struct console *con, const char *str, unsigned n)
27 {
28 char c;
29 int i, k, j;
30
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));
38 }
39 }
40 for (i = 0; i < max_xpos; i++)
41 writew(0x720, VGABASE + 2*(max_xpos*j + i));
42 current_ypos = max_ypos-1;
43 }
44 if (c == '\n') {
45 current_xpos = 0;
46 current_ypos++;
47 } else if (c != '\r') {
48 writew(((0x7 << 8) | (unsigned short) c),
49 VGABASE + 2*(max_xpos*current_ypos +
50 current_xpos++));
51 if (current_xpos >= max_xpos) {
52 current_xpos = 0;
53 current_ypos++;
54 }
55 }
56 }
57 }
58
59 static struct console early_vga_console = {
60 .name = "earlyvga",
61 .write = early_vga_write,
62 .flags = CON_PRINTBUFFER,
63 .index = -1,
64 };
65
66 /* Serial functions loosely based on a similar package from Klaus P. Gerlicher */
67
68 static int early_serial_base = 0x3f8; /* ttyS0 */
69
70 #define XMTRDY 0x20
71
72 #define DLAB 0x80
73
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 */
85
86 static int early_serial_putc(unsigned char ch)
87 {
88 unsigned timeout = 0xffff;
89
90 while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
91 cpu_relax();
92 outb(ch, early_serial_base + TXR);
93 return timeout ? 0 : -1;
94 }
95
96 static void early_serial_write(struct console *con, const char *s, unsigned n)
97 {
98 while (*s && n-- > 0) {
99 if (*s == '\n')
100 early_serial_putc('\r');
101 early_serial_putc(*s);
102 s++;
103 }
104 }
105
106 #define DEFAULT_BAUD 9600
107
108 static __init void early_serial_init(char *s)
109 {
110 unsigned char c;
111 unsigned divisor;
112 unsigned baud = DEFAULT_BAUD;
113 char *e;
114
115 if (*s == ',')
116 ++s;
117
118 if (*s) {
119 unsigned port;
120 if (!strncmp(s, "0x", 2)) {
121 early_serial_base = simple_strtoul(s, &e, 16);
122 } else {
123 static const int __initconst bases[] = { 0x3f8, 0x2f8 };
124
125 if (!strncmp(s, "ttyS", 4))
126 s += 4;
127 port = simple_strtoul(s, &e, 10);
128 if (port > 1 || s == e)
129 port = 0;
130 early_serial_base = bases[port];
131 }
132 s += strcspn(s, ",");
133 if (*s == ',')
134 s++;
135 }
136
137 outb(0x3, early_serial_base + LCR); /* 8n1 */
138 outb(0, early_serial_base + IER); /* no interrupt */
139 outb(0, early_serial_base + FCR); /* no fifo */
140 outb(0x3, early_serial_base + MCR); /* DTR + RTS */
141
142 if (*s) {
143 baud = simple_strtoul(s, &e, 0);
144 if (baud == 0 || s == e)
145 baud = DEFAULT_BAUD;
146 }
147
148 divisor = 115200 / baud;
149 c = inb(early_serial_base + LCR);
150 outb(c | DLAB, early_serial_base + LCR);
151 outb(divisor & 0xff, early_serial_base + DLL);
152 outb((divisor >> 8) & 0xff, early_serial_base + DLH);
153 outb(c & ~DLAB, early_serial_base + LCR);
154 }
155
156 static struct console early_serial_console = {
157 .name = "earlyser",
158 .write = early_serial_write,
159 .flags = CON_PRINTBUFFER,
160 .index = -1,
161 };
162
163 /* Direct interface for emergencies */
164 static struct console *early_console = &early_vga_console;
165 static int __initdata early_console_initialized;
166
167 asmlinkage void early_printk(const char *fmt, ...)
168 {
169 char buf[512];
170 int n;
171 va_list ap;
172
173 va_start(ap, fmt);
174 n = vscnprintf(buf, sizeof(buf), fmt, ap);
175 early_console->write(early_console, buf, n);
176 va_end(ap);
177 }
178
179 static inline void early_console_register(struct console *con, int keep_early)
180 {
181 if (early_console->index != -1) {
182 printk(KERN_CRIT "ERROR: earlyprintk= %s already used\n",
183 con->name);
184 return;
185 }
186 early_console = con;
187 if (keep_early)
188 early_console->flags &= ~CON_BOOT;
189 else
190 early_console->flags |= CON_BOOT;
191 register_console(early_console);
192 }
193
194 static int __init setup_early_printk(char *buf)
195 {
196 int keep;
197
198 if (!buf)
199 return 0;
200
201 if (early_console_initialized)
202 return 0;
203 early_console_initialized = 1;
204
205 keep = (strstr(buf, "keep") != NULL);
206
207 while (*buf != '\0') {
208 if (!strncmp(buf, "serial", 6)) {
209 buf += 6;
210 early_serial_init(buf);
211 early_console_register(&early_serial_console, keep);
212 if (!strncmp(buf, ",ttyS", 5))
213 buf += 5;
214 }
215 if (!strncmp(buf, "ttyS", 4)) {
216 early_serial_init(buf + 4);
217 early_console_register(&early_serial_console, keep);
218 }
219 if (!strncmp(buf, "vga", 3) &&
220 boot_params.screen_info.orig_video_isVGA == 1) {
221 max_xpos = boot_params.screen_info.orig_video_cols;
222 max_ypos = boot_params.screen_info.orig_video_lines;
223 current_ypos = boot_params.screen_info.orig_y;
224 early_console_register(&early_vga_console, keep);
225 }
226 #ifdef CONFIG_EARLY_PRINTK_DBGP
227 if (!strncmp(buf, "dbgp", 4) && !early_dbgp_init(buf + 4))
228 early_console_register(&early_dbgp_console, keep);
229 #endif
230 #ifdef CONFIG_HVC_XEN
231 if (!strncmp(buf, "xen", 3))
232 early_console_register(&xenboot_console, keep);
233 #endif
234 buf++;
235 }
236 return 0;
237 }
238
239 early_param("earlyprintk", setup_early_printk);