1 /*
2 * linux/arch/m68k/mac/debug.c
3 *
4 * Shamelessly stolen (SCC code and general framework) from:
5 *
6 * linux/arch/m68k/atari/debug.c
7 *
8 * Atari debugging and serial console stuff
9 *
10 * Assembled of parts of former atari/config.c 97-12-18 by Roman Hodek
11 *
12 * This file is subject to the terms and conditions of the GNU General Public
13 * License. See the file COPYING in the main directory of this archive
14 * for more details.
15 */
16
17 #include <linux/types.h>
18 #include <linux/sched.h>
19 #include <linux/tty.h>
20 #include <linux/console.h>
21 #include <linux/init.h>
22 #include <linux/delay.h>
23
24 #define BOOTINFO_COMPAT_1_0
25 #include <asm/setup.h>
26 #include <asm/bootinfo.h>
27 #include <asm/macints.h>
28
29 extern unsigned long mac_videobase;
30 extern unsigned long mac_rowbytes;
31
32 extern void mac_serial_print(const char *);
33
34 #define DEBUG_HEADS
35 #undef DEBUG_SCREEN
36 #define DEBUG_SERIAL
37
38 /*
39 * These two auxiliary debug functions should go away ASAP. Only usage:
40 * before the console output is up (after head.S come some other crucial
41 * setup routines :-) it permits writing 'data' to the screen as bit patterns
42 * (good luck reading those). Helped to figure that the bootinfo contained
43 * garbage data on the amount and size of memory chunks ...
44 *
45 * The 'pos' argument now simply means 'linefeed after print' ...
46 */
47
48 #ifdef DEBUG_SCREEN
49 static int peng, line;
50 #endif
51
52 #if 0
53
54 void mac_debugging_short(int pos, short num)
55 {
56 #ifdef DEBUG_SCREEN
57 unsigned char *pengoffset;
58 unsigned char *pptr;
59 int i;
60 #endif
61
62 #ifdef DEBUG_SERIAL
63 printk("debug: %d !\n", num);
64 #endif
65
66 #ifdef DEBUG_SCREEN
67 if (!MACH_IS_MAC) {
68 /* printk("debug: %d !\n", num); */
69 return;
70 }
71
72 /* calculate current offset */
73 pengoffset = (unsigned char *)mac_videobase +
74 (150+line*2) * mac_rowbytes + 80 * peng;
75
76 pptr = pengoffset;
77
78 for (i = 0; i < 8 * sizeof(short); i++) { /* # of bits */
79 /* value mask for bit i, reverse order */
80 *pptr++ = (num & (1 << (8*sizeof(short)-i-1)) ? 0xFF : 0x00);
81 }
82
83 peng++;
84
85 if (pos) {
86 line++;
87 peng = 0;
88 }
89 #endif
90 }
91
92 void mac_debugging_long(int pos, long addr)
93 {
94 #ifdef DEBUG_SCREEN
95 unsigned char *pengoffset;
96 unsigned char *pptr;
97 int i;
98 #endif
99
100 #ifdef DEBUG_SERIAL
101 printk("debug: #%ld !\n", addr);
102 #endif
103
104 #ifdef DEBUG_SCREEN
105 if (!MACH_IS_MAC) {
106 /* printk("debug: #%ld !\n", addr); */
107 return;
108 }
109
110 pengoffset=(unsigned char *)(mac_videobase+(150+line*2)*mac_rowbytes)
111 +80*peng;
112
113 pptr = pengoffset;
114
115 for (i = 0; i < 8 * sizeof(long); i++) { /* # of bits */
116 *pptr++ = (addr & (1 << (8*sizeof(long)-i-1)) ? 0xFF : 0x00);
117 }
118
119 peng++;
120
121 if (pos) {
122 line++;
123 peng = 0;
124 }
125 #endif
126 }
127
128 #endif /* 0 */
129
130 #ifdef DEBUG_SERIAL
131 /*
132 * TODO: serial debug code
133 */
134
135 struct mac_SCC {
136 u_char cha_b_ctrl;
137 u_char char_dummy1;
138 u_char cha_a_ctrl;
139 u_char char_dummy2;
140 u_char cha_b_data;
141 u_char char_dummy3;
142 u_char cha_a_data;
143 };
144
145 # define scc (*((volatile struct mac_SCC*)mac_bi_data.sccbase))
146
147 static int scc_port = -1;
148
149 static struct console mac_console_driver = {
150 .name = "debug",
151 .flags = CON_PRINTBUFFER,
152 .index = -1,
153 };
154
155 /*
156 * Crude hack to get console output to the screen before the framebuffer
157 * is initialized (happens a lot later in 2.1!).
158 * We just use the console routines declared in head.S, this will interfere
159 * with regular framebuffer console output and should be used exclusively
160 * to debug kernel problems manifesting before framebuffer init (aka WSOD)
161 *
162 * To keep this hack from interfering with the regular console driver, either
163 * deregister this driver before/on framebuffer console init, or silence this
164 * function after the fbcon driver is running (will lose console messages!?).
165 * To debug real early bugs, need to write a 'mac_register_console_hack()'
166 * that is called from start_kernel() before setup_arch() and just registers
167 * this driver if Mac.
168 */
169
mac_debug_console_write(struct console * co,const char * str,unsigned int count)170 static void mac_debug_console_write(struct console *co, const char *str,
171 unsigned int count)
172 {
173 mac_serial_print(str);
174 }
175
176
177
178 /* Mac: loops_per_jiffy min. 19000 ^= .5 us; MFPDELAY was 0.6 us*/
179
180 #define uSEC 1
181
mac_sccb_out(char c)182 static inline void mac_sccb_out(char c)
183 {
184 int i;
185
186 do {
187 for (i = uSEC; i > 0; --i)
188 barrier();
189 } while (!(scc.cha_b_ctrl & 0x04)); /* wait for tx buf empty */
190 for (i = uSEC; i > 0; --i)
191 barrier();
192 scc.cha_b_data = c;
193 }
194
mac_scca_out(char c)195 static inline void mac_scca_out(char c)
196 {
197 int i;
198
199 do {
200 for (i = uSEC; i > 0; --i)
201 barrier();
202 } while (!(scc.cha_a_ctrl & 0x04)); /* wait for tx buf empty */
203 for (i = uSEC; i > 0; --i)
204 barrier();
205 scc.cha_a_data = c;
206 }
207
mac_sccb_console_write(struct console * co,const char * str,unsigned int count)208 static void mac_sccb_console_write(struct console *co, const char *str,
209 unsigned int count)
210 {
211 while (count--) {
212 if (*str == '\n')
213 mac_sccb_out('\r');
214 mac_sccb_out(*str++);
215 }
216 }
217
mac_scca_console_write(struct console * co,const char * str,unsigned int count)218 static void mac_scca_console_write(struct console *co, const char *str,
219 unsigned int count)
220 {
221 while (count--) {
222 if (*str == '\n')
223 mac_scca_out('\r');
224 mac_scca_out(*str++);
225 }
226 }
227
228
229 /* The following two functions do a quick'n'dirty initialization of the MFP or
230 * SCC serial ports. They're used by the debugging interface, kgdb, and the
231 * serial console code. */
232 #define SCCB_WRITE(reg,val) \
233 do { \
234 int i; \
235 scc.cha_b_ctrl = (reg); \
236 for (i = uSEC; i > 0; --i) \
237 barrier(); \
238 scc.cha_b_ctrl = (val); \
239 for (i = uSEC; i > 0; --i) \
240 barrier(); \
241 } while(0)
242
243 #define SCCA_WRITE(reg,val) \
244 do { \
245 int i; \
246 scc.cha_a_ctrl = (reg); \
247 for (i = uSEC; i > 0; --i) \
248 barrier(); \
249 scc.cha_a_ctrl = (val); \
250 for (i = uSEC; i > 0; --i) \
251 barrier(); \
252 } while(0)
253
254 /* loops_per_jiffy isn't initialized yet, so we can't use udelay(). This does a
255 * delay of ~ 60us. */
256 /* Mac: loops_per_jiffy min. 19000 ^= .5 us; MFPDELAY was 0.6 us*/
257 #define LONG_DELAY() \
258 do { \
259 int i; \
260 for (i = 60*uSEC; i > 0; --i) \
261 barrier(); \
262 } while(0)
263
mac_init_scc_port(int cflag,int port)264 static void __init mac_init_scc_port(int cflag, int port)
265 {
266 /*
267 * baud rates: 1200, 1800, 2400, 4800, 9600, 19.2k, 38.4k, 57.6k, 115.2k
268 */
269
270 static int clksrc_table[9] =
271 /* reg 11: 0x50 = BRG, 0x00 = RTxC, 0x28 = TRxC */
272 { 0x50, 0x50, 0x50, 0x50, 0x50, 0x50, 0x50, 0x00, 0x00 };
273 static int clkmode_table[9] =
274 /* reg 4: 0x40 = x16, 0x80 = x32, 0xc0 = x64 */
275 { 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0xc0, 0x80 };
276 static int div_table[9] =
277 /* reg12 (BRG low) */
278 { 94, 62, 46, 22, 10, 4, 1, 0, 0 };
279
280 int baud = cflag & CBAUD;
281 int clksrc, clkmode, div, reg3, reg5;
282
283 if (cflag & CBAUDEX)
284 baud += B38400;
285 if (baud < B1200 || baud > B38400+2)
286 baud = B9600; /* use default 9600bps for non-implemented rates */
287 baud -= B1200; /* tables starts at 1200bps */
288
289 clksrc = clksrc_table[baud];
290 clkmode = clkmode_table[baud];
291 div = div_table[baud];
292
293 reg3 = (((cflag & CSIZE) == CS8) ? 0xc0 : 0x40);
294 reg5 = (((cflag & CSIZE) == CS8) ? 0x60 : 0x20) | 0x82 /* assert DTR/RTS */;
295
296 if (port == 1) {
297 (void)scc.cha_b_ctrl; /* reset reg pointer */
298 SCCB_WRITE(9, 0xc0); /* reset */
299 LONG_DELAY(); /* extra delay after WR9 access */
300 SCCB_WRITE(4, (cflag & PARENB) ? ((cflag & PARODD) ? 0x01 : 0x03) : 0 |
301 0x04 /* 1 stopbit */ |
302 clkmode);
303 SCCB_WRITE(3, reg3);
304 SCCB_WRITE(5, reg5);
305 SCCB_WRITE(9, 0); /* no interrupts */
306 LONG_DELAY(); /* extra delay after WR9 access */
307 SCCB_WRITE(10, 0); /* NRZ mode */
308 SCCB_WRITE(11, clksrc); /* main clock source */
309 SCCB_WRITE(12, div); /* BRG value */
310 SCCB_WRITE(13, 0); /* BRG high byte */
311 SCCB_WRITE(14, 1);
312 SCCB_WRITE(3, reg3 | 1);
313 SCCB_WRITE(5, reg5 | 8);
314 } else if (port == 0) {
315 (void)scc.cha_a_ctrl; /* reset reg pointer */
316 SCCA_WRITE(9, 0xc0); /* reset */
317 LONG_DELAY(); /* extra delay after WR9 access */
318 SCCA_WRITE(4, (cflag & PARENB) ? ((cflag & PARODD) ? 0x01 : 0x03) : 0 |
319 0x04 /* 1 stopbit */ |
320 clkmode);
321 SCCA_WRITE(3, reg3);
322 SCCA_WRITE(5, reg5);
323 SCCA_WRITE(9, 0); /* no interrupts */
324 LONG_DELAY(); /* extra delay after WR9 access */
325 SCCA_WRITE(10, 0); /* NRZ mode */
326 SCCA_WRITE(11, clksrc); /* main clock source */
327 SCCA_WRITE(12, div); /* BRG value */
328 SCCA_WRITE(13, 0); /* BRG high byte */
329 SCCA_WRITE(14, 1);
330 SCCA_WRITE(3, reg3 | 1);
331 SCCA_WRITE(5, reg5 | 8);
332 }
333 }
334 #endif /* DEBUG_SERIAL */
335
mac_debug_setup(char * arg)336 static int __init mac_debug_setup(char *arg)
337 {
338 if (!MACH_IS_MAC)
339 return 0;
340
341 #ifdef DEBUG_SERIAL
342 if (!strcmp(arg, "ser") || !strcmp(arg, "ser1")) {
343 /* Mac modem port */
344 mac_init_scc_port(B9600|CS8, 0);
345 mac_console_driver.write = mac_scca_console_write;
346 scc_port = 0;
347 } else if (!strcmp(arg, "ser2")) {
348 /* Mac printer port */
349 mac_init_scc_port(B9600|CS8, 1);
350 mac_console_driver.write = mac_sccb_console_write;
351 scc_port = 1;
352 }
353 #endif
354 #ifdef DEBUG_HEADS
355 if (!strcmp(arg, "scn") || !strcmp(arg, "con")) {
356 /* display, using head.S console routines */
357 mac_console_driver.write = mac_debug_console_write;
358 }
359 #endif
360 if (mac_console_driver.write)
361 register_console(&mac_console_driver);
362 return 0;
363 }
364
365 early_param("debug", mac_debug_setup);
366