1 /*
2 * NS16550 Serial Port (uart) debugging stuff.
3 *
4 * c 2001 PPC 64 Team, IBM Corp
5 *
6 * NOTE: I am trying to make this code avoid any static data references to
7 * simplify debugging early boot. We'll see how that goes...
8 *
9 * To use this call udbg_init() first. It will init the uart to 9600 8N1.
10 * You may need to update the COM1 define if your uart is at a different addr.
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
16 */
17
18 #include <stdarg.h>
19 #define WANT_PPCDBG_TAB /* Only defined here */
20 #include <asm/ppcdebug.h>
21 #include <asm/processor.h>
22 #include <asm/naca.h>
23 #include <asm/uaccess.h>
24 #include <asm/machdep.h>
25
26 struct NS16550 {
27 /* this struct must be packed */
28 unsigned char rbr; /* 0 */
29 unsigned char ier; /* 1 */
30 unsigned char fcr; /* 2 */
31 unsigned char lcr; /* 3 */
32 unsigned char mcr; /* 4 */
33 unsigned char lsr; /* 5 */
34 unsigned char msr; /* 6 */
35 unsigned char scr; /* 7 */
36 };
37
38 #define thr rbr
39 #define iir fcr
40 #define dll rbr
41 #define dlm ier
42 #define dlab lcr
43
44 #define LSR_DR 0x01 /* Data ready */
45 #define LSR_OE 0x02 /* Overrun */
46 #define LSR_PE 0x04 /* Parity error */
47 #define LSR_FE 0x08 /* Framing error */
48 #define LSR_BI 0x10 /* Break */
49 #define LSR_THRE 0x20 /* Xmit holding register empty */
50 #define LSR_TEMT 0x40 /* Xmitter empty */
51 #define LSR_ERR 0x80 /* Error */
52
53 volatile struct NS16550 *udbg_comport;
54
55 void
udbg_init_uart(void * comport)56 udbg_init_uart(void *comport)
57 {
58 if (comport) {
59 udbg_comport = (struct NS16550 *)comport;
60 udbg_comport->lcr = 0x00; eieio();
61 udbg_comport->ier = 0xFF; eieio();
62 udbg_comport->ier = 0x00; eieio();
63 udbg_comport->lcr = 0x80; eieio(); /* Access baud rate */
64 udbg_comport->dll = 12; eieio(); /* 1 = 115200, 2 = 57600, 3 = 38400, 12 = 9600 baud */
65 udbg_comport->dlm = 0; eieio(); /* dll >> 8 which should be zero for fast rates; */
66 udbg_comport->lcr = 0x03; eieio(); /* 8 data, 1 stop, no parity */
67 udbg_comport->mcr = 0x03; eieio(); /* RTS/DTR */
68 udbg_comport->fcr = 0x07; eieio(); /* Clear & enable FIFOs */
69 }
70 }
71
72 void
udbg_putc(unsigned char c)73 udbg_putc(unsigned char c)
74 {
75 if ( udbg_comport ) {
76 while ((udbg_comport->lsr & LSR_THRE) == 0)
77 /* wait for idle */;
78 udbg_comport->thr = c; eieio();
79 if (c == '\n') {
80 /* Also put a CR. This is for convenience. */
81 while ((udbg_comport->lsr & LSR_THRE) == 0)
82 /* wait for idle */;
83 udbg_comport->thr = '\r'; eieio();
84 }
85 } else if (systemcfg->platform == PLATFORM_ISERIES_LPAR) {
86 /* ToDo: switch this via ppc_md */
87 printk("%c", c);
88 }
89 }
90
udbg_getc_poll(void)91 int udbg_getc_poll(void)
92 {
93 if (udbg_comport) {
94 if ((udbg_comport->lsr & LSR_DR) != 0)
95 return udbg_comport->rbr;
96 else
97 return -1;
98 }
99 return -1;
100 }
101
102 unsigned char
udbg_getc(void)103 udbg_getc(void)
104 {
105 if ( udbg_comport ) {
106 while ((udbg_comport->lsr & LSR_DR) == 0)
107 /* wait for char */;
108 return udbg_comport->rbr;
109 }
110 return 0;
111 }
112
113 void
udbg_puts(const char * s)114 udbg_puts(const char *s)
115 {
116 if (ppc_md.udbg_putc) {
117 char c;
118
119 if (s && *s != '\0') {
120 while ((c = *s++) != '\0')
121 ppc_md.udbg_putc(c);
122 }
123 } else {
124 printk("%s", s);
125 }
126 }
127
128 int
udbg_write(const char * s,int n)129 udbg_write(const char *s, int n)
130 {
131 int remain = n;
132 char c;
133
134 if (!ppc_md.udbg_putc)
135 return 0;
136
137 if ( s && *s != '\0' ) {
138 while ( (( c = *s++ ) != '\0') && (remain-- > 0)) {
139 ppc_md.udbg_putc(c);
140 }
141 }
142 return n - remain;
143 }
144
145 int
udbg_read(char * buf,int buflen)146 udbg_read(char *buf, int buflen) {
147 char c, *p = buf;
148 int i;
149 if (!ppc_md.udbg_putc)
150 for (;;); /* stop here for cpuctl */
151 for (i = 0; i < buflen; ++i) {
152 do {
153 c = ppc_md.udbg_getc();
154 } while (c == 0x11 || c == 0x13);
155 *p++ = c;
156 }
157 return i;
158 }
159
160 void
udbg_console_write(struct console * con,const char * s,unsigned int n)161 udbg_console_write(struct console *con, const char *s, unsigned int n)
162 {
163 udbg_write(s, n);
164 }
165
166 void
udbg_puthex(unsigned long val)167 udbg_puthex(unsigned long val)
168 {
169 int i, nibbles = sizeof(val)*2;
170 unsigned char buf[sizeof(val)*2+1];
171 for (i = nibbles-1; i >= 0; i--) {
172 buf[i] = (val & 0xf) + '0';
173 if (buf[i] > '9')
174 buf[i] += ('a'-'0'-10);
175 val >>= 4;
176 }
177 buf[nibbles] = '\0';
178 udbg_puts(buf);
179 }
180
181 void
udbg_printSP(const char * s)182 udbg_printSP(const char *s)
183 {
184 if (systemcfg->platform == PLATFORM_PSERIES) {
185 unsigned long sp;
186 asm("mr %0,1" : "=r" (sp) :);
187 if (s)
188 udbg_puts(s);
189 udbg_puthex(sp);
190 }
191 }
192
193 void
udbg_printf(const char * fmt,...)194 udbg_printf(const char *fmt, ...)
195 {
196 unsigned char buf[256];
197
198 va_list args;
199 va_start(args, fmt);
200
201 vsprintf(buf, fmt, args);
202 udbg_puts(buf);
203
204 va_end(args);
205 }
206
207 /* Special print used by PPCDBG() macro */
208 void
udbg_ppcdbg(unsigned long debug_flags,const char * fmt,...)209 udbg_ppcdbg(unsigned long debug_flags, const char *fmt, ...)
210 {
211 unsigned long active_debugs = debug_flags & naca->debug_switch;
212
213 if ( active_debugs ) {
214 va_list ap;
215 unsigned char buf[256];
216 unsigned long i, len = 0;
217
218 for(i=0; i < PPCDBG_NUM_FLAGS ;i++) {
219 if (((1U << i) & active_debugs) &&
220 trace_names[i]) {
221 len += strlen(trace_names[i]);
222 udbg_puts(trace_names[i]);
223 break;
224 }
225 }
226 sprintf(buf, " [%s]: ", current->comm);
227 len += strlen(buf);
228 udbg_puts(buf);
229
230 while(len < 18) {
231 udbg_puts(" ");
232 len++;
233 }
234
235 va_start(ap, fmt);
236 vsprintf(buf, fmt, ap);
237 udbg_puts(buf);
238
239 va_end(ap);
240 }
241 }
242
243 unsigned long
udbg_ifdebug(unsigned long flags)244 udbg_ifdebug(unsigned long flags)
245 {
246 return (flags & naca->debug_switch);
247 }
248