1 /*
2 * linux/arch/m68k/atari/debug.c
3 *
4 * Atari debugging and serial console stuff
5 *
6 * Assembled of parts of former atari/config.c 97-12-18 by Roman Hodek
7 *
8 * This file is subject to the terms and conditions of the GNU General Public
9 * License. See the file COPYING in the main directory of this archive
10 * for more details.
11 */
12
13 #include <linux/types.h>
14 #include <linux/tty.h>
15 #include <linux/console.h>
16 #include <linux/init.h>
17 #include <linux/delay.h>
18 #include <linux/module.h>
19
20 #include <asm/atarihw.h>
21 #include <asm/atariints.h>
22
23 /* Can be set somewhere, if a SCC master reset has already be done and should
24 * not be repeated; used by kgdb */
25 int atari_SCC_reset_done;
26 EXPORT_SYMBOL(atari_SCC_reset_done);
27
28 static struct console atari_console_driver = {
29 .name = "debug",
30 .flags = CON_PRINTBUFFER,
31 .index = -1,
32 };
33
34
ata_mfp_out(char c)35 static inline void ata_mfp_out(char c)
36 {
37 while (!(st_mfp.trn_stat & 0x80)) /* wait for tx buf empty */
38 barrier();
39 st_mfp.usart_dta = c;
40 }
41
atari_mfp_console_write(struct console * co,const char * str,unsigned int count)42 static void atari_mfp_console_write(struct console *co, const char *str,
43 unsigned int count)
44 {
45 while (count--) {
46 if (*str == '\n')
47 ata_mfp_out('\r');
48 ata_mfp_out(*str++);
49 }
50 }
51
ata_scc_out(char c)52 static inline void ata_scc_out(char c)
53 {
54 do {
55 MFPDELAY();
56 } while (!(atari_scc.cha_b_ctrl & 0x04)); /* wait for tx buf empty */
57 MFPDELAY();
58 atari_scc.cha_b_data = c;
59 }
60
atari_scc_console_write(struct console * co,const char * str,unsigned int count)61 static void atari_scc_console_write(struct console *co, const char *str,
62 unsigned int count)
63 {
64 while (count--) {
65 if (*str == '\n')
66 ata_scc_out('\r');
67 ata_scc_out(*str++);
68 }
69 }
70
ata_midi_out(char c)71 static inline void ata_midi_out(char c)
72 {
73 while (!(acia.mid_ctrl & ACIA_TDRE)) /* wait for tx buf empty */
74 barrier();
75 acia.mid_data = c;
76 }
77
atari_midi_console_write(struct console * co,const char * str,unsigned int count)78 static void atari_midi_console_write(struct console *co, const char *str,
79 unsigned int count)
80 {
81 while (count--) {
82 if (*str == '\n')
83 ata_midi_out('\r');
84 ata_midi_out(*str++);
85 }
86 }
87
ata_par_out(char c)88 static int ata_par_out(char c)
89 {
90 unsigned char tmp;
91 /* This a some-seconds timeout in case no printer is connected */
92 unsigned long i = loops_per_jiffy > 1 ? loops_per_jiffy : 10000000/HZ;
93
94 while ((st_mfp.par_dt_reg & 1) && --i) /* wait for BUSY == L */
95 ;
96 if (!i)
97 return 0;
98
99 sound_ym.rd_data_reg_sel = 15; /* select port B */
100 sound_ym.wd_data = c; /* put char onto port */
101 sound_ym.rd_data_reg_sel = 14; /* select port A */
102 tmp = sound_ym.rd_data_reg_sel;
103 sound_ym.wd_data = tmp & ~0x20; /* set strobe L */
104 MFPDELAY(); /* wait a bit */
105 sound_ym.wd_data = tmp | 0x20; /* set strobe H */
106 return 1;
107 }
108
atari_par_console_write(struct console * co,const char * str,unsigned int count)109 static void atari_par_console_write(struct console *co, const char *str,
110 unsigned int count)
111 {
112 static int printer_present = 1;
113
114 if (!printer_present)
115 return;
116
117 while (count--) {
118 if (*str == '\n') {
119 if (!ata_par_out('\r')) {
120 printer_present = 0;
121 return;
122 }
123 }
124 if (!ata_par_out(*str++)) {
125 printer_present = 0;
126 return;
127 }
128 }
129 }
130
131 #if 0
132 int atari_mfp_console_wait_key(struct console *co)
133 {
134 while (!(st_mfp.rcv_stat & 0x80)) /* wait for rx buf filled */
135 barrier();
136 return st_mfp.usart_dta;
137 }
138
139 int atari_scc_console_wait_key(struct console *co)
140 {
141 do {
142 MFPDELAY();
143 } while (!(atari_scc.cha_b_ctrl & 0x01)); /* wait for rx buf filled */
144 MFPDELAY();
145 return atari_scc.cha_b_data;
146 }
147
148 int atari_midi_console_wait_key(struct console *co)
149 {
150 while (!(acia.mid_ctrl & ACIA_RDRF)) /* wait for rx buf filled */
151 barrier();
152 return acia.mid_data;
153 }
154 #endif
155
156 /*
157 * The following two functions do a quick'n'dirty initialization of the MFP or
158 * SCC serial ports. They're used by the debugging interface, kgdb, and the
159 * serial console code.
160 */
atari_init_mfp_port(int cflag)161 static void __init atari_init_mfp_port(int cflag)
162 {
163 /*
164 * timer values for 1200...115200 bps; > 38400 select 110, 134, or 150
165 * bps, resp., and work only correct if there's a RSVE or RSSPEED
166 */
167 static int baud_table[9] = { 16, 11, 8, 4, 2, 1, 175, 143, 128 };
168 int baud = cflag & CBAUD;
169 int parity = (cflag & PARENB) ? ((cflag & PARODD) ? 0x04 : 0x06) : 0;
170 int csize = ((cflag & CSIZE) == CS7) ? 0x20 : 0x00;
171
172 if (cflag & CBAUDEX)
173 baud += B38400;
174 if (baud < B1200 || baud > B38400+2)
175 baud = B9600; /* use default 9600bps for non-implemented rates */
176 baud -= B1200; /* baud_table[] starts at 1200bps */
177
178 st_mfp.trn_stat &= ~0x01; /* disable TX */
179 st_mfp.usart_ctr = parity | csize | 0x88; /* 1:16 clk mode, 1 stop bit */
180 st_mfp.tim_ct_cd &= 0x70; /* stop timer D */
181 st_mfp.tim_dt_d = baud_table[baud];
182 st_mfp.tim_ct_cd |= 0x01; /* start timer D, 1:4 */
183 st_mfp.trn_stat |= 0x01; /* enable TX */
184 }
185
186 #define SCC_WRITE(reg, val) \
187 do { \
188 atari_scc.cha_b_ctrl = (reg); \
189 MFPDELAY(); \
190 atari_scc.cha_b_ctrl = (val); \
191 MFPDELAY(); \
192 } while (0)
193
194 /* loops_per_jiffy isn't initialized yet, so we can't use udelay(). This does a
195 * delay of ~ 60us. */
196 #define LONG_DELAY() \
197 do { \
198 int i; \
199 for (i = 100; i > 0; --i) \
200 MFPDELAY(); \
201 } while (0)
202
atari_init_scc_port(int cflag)203 static void __init atari_init_scc_port(int cflag)
204 {
205 static int clksrc_table[9] =
206 /* reg 11: 0x50 = BRG, 0x00 = RTxC, 0x28 = TRxC */
207 { 0x50, 0x50, 0x50, 0x50, 0x50, 0x50, 0x50, 0x00, 0x00 };
208 static int brgsrc_table[9] =
209 /* reg 14: 0 = RTxC, 2 = PCLK */
210 { 2, 2, 2, 2, 2, 2, 0, 2, 2 };
211 static int clkmode_table[9] =
212 /* reg 4: 0x40 = x16, 0x80 = x32, 0xc0 = x64 */
213 { 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0xc0, 0x80 };
214 static int div_table[9] =
215 /* reg12 (BRG low) */
216 { 208, 138, 103, 50, 24, 11, 1, 0, 0 };
217
218 int baud = cflag & CBAUD;
219 int clksrc, clkmode, div, reg3, reg5;
220
221 if (cflag & CBAUDEX)
222 baud += B38400;
223 if (baud < B1200 || baud > B38400+2)
224 baud = B9600; /* use default 9600bps for non-implemented rates */
225 baud -= B1200; /* tables starts at 1200bps */
226
227 clksrc = clksrc_table[baud];
228 clkmode = clkmode_table[baud];
229 div = div_table[baud];
230 if (ATARIHW_PRESENT(TT_MFP) && baud >= 6) {
231 /* special treatment for TT, where rates >= 38400 are done via TRxC */
232 clksrc = 0x28; /* TRxC */
233 clkmode = baud == 6 ? 0xc0 :
234 baud == 7 ? 0x80 : /* really 76800bps */
235 0x40; /* really 153600bps */
236 div = 0;
237 }
238
239 reg3 = (cflag & CSIZE) == CS8 ? 0xc0 : 0x40;
240 reg5 = (cflag & CSIZE) == CS8 ? 0x60 : 0x20 | 0x82 /* assert DTR/RTS */;
241
242 (void)atari_scc.cha_b_ctrl; /* reset reg pointer */
243 SCC_WRITE(9, 0xc0); /* reset */
244 LONG_DELAY(); /* extra delay after WR9 access */
245 SCC_WRITE(4, (cflag & PARENB) ? ((cflag & PARODD) ? 0x01 : 0x03)
246 : 0 | 0x04 /* 1 stopbit */ | clkmode);
247 SCC_WRITE(3, reg3);
248 SCC_WRITE(5, reg5);
249 SCC_WRITE(9, 0); /* no interrupts */
250 LONG_DELAY(); /* extra delay after WR9 access */
251 SCC_WRITE(10, 0); /* NRZ mode */
252 SCC_WRITE(11, clksrc); /* main clock source */
253 SCC_WRITE(12, div); /* BRG value */
254 SCC_WRITE(13, 0); /* BRG high byte */
255 SCC_WRITE(14, brgsrc_table[baud]);
256 SCC_WRITE(14, brgsrc_table[baud] | (div ? 1 : 0));
257 SCC_WRITE(3, reg3 | 1);
258 SCC_WRITE(5, reg5 | 8);
259
260 atari_SCC_reset_done = 1;
261 }
262
atari_init_midi_port(int cflag)263 static void __init atari_init_midi_port(int cflag)
264 {
265 int baud = cflag & CBAUD;
266 int csize = ((cflag & CSIZE) == CS8) ? 0x10 : 0x00;
267 /* warning 7N1 isn't possible! (instead 7O2 is used...) */
268 int parity = (cflag & PARENB) ? ((cflag & PARODD) ? 0x0c : 0x08) : 0x04;
269 int div;
270
271 /* 4800 selects 7812.5, 115200 selects 500000, all other (incl. 9600 as
272 * default) the standard MIDI speed 31250. */
273 if (cflag & CBAUDEX)
274 baud += B38400;
275 if (baud == B4800)
276 div = ACIA_DIV64; /* really 7812.5 bps */
277 else if (baud == B38400+2 /* 115200 */)
278 div = ACIA_DIV1; /* really 500 kbps (does that work??) */
279 else
280 div = ACIA_DIV16; /* 31250 bps, standard for MIDI */
281
282 /* RTS low, ints disabled */
283 acia.mid_ctrl = div | csize | parity |
284 ((atari_switches & ATARI_SWITCH_MIDI) ?
285 ACIA_RHTID : ACIA_RLTID);
286 }
287
atari_debug_setup(char * arg)288 static int __init atari_debug_setup(char *arg)
289 {
290 bool registered;
291
292 if (!MACH_IS_ATARI)
293 return 0;
294
295 if (!strcmp(arg, "ser"))
296 /* defaults to ser2 for a Falcon and ser1 otherwise */
297 arg = MACH_IS_FALCON ? "ser2" : "ser1";
298
299 registered = !!atari_console_driver.write;
300 if (!strcmp(arg, "ser1")) {
301 /* ST-MFP Modem1 serial port */
302 atari_init_mfp_port(B9600|CS8);
303 atari_console_driver.write = atari_mfp_console_write;
304 } else if (!strcmp(arg, "ser2")) {
305 /* SCC Modem2 serial port */
306 atari_init_scc_port(B9600|CS8);
307 atari_console_driver.write = atari_scc_console_write;
308 } else if (!strcmp(arg, "midi")) {
309 /* MIDI port */
310 atari_init_midi_port(B9600|CS8);
311 atari_console_driver.write = atari_midi_console_write;
312 } else if (!strcmp(arg, "par")) {
313 /* parallel printer */
314 atari_turnoff_irq(IRQ_MFP_BUSY); /* avoid ints */
315 sound_ym.rd_data_reg_sel = 7; /* select mixer control */
316 sound_ym.wd_data = 0xff; /* sound off, ports are output */
317 sound_ym.rd_data_reg_sel = 15; /* select port B */
318 sound_ym.wd_data = 0; /* no char */
319 sound_ym.rd_data_reg_sel = 14; /* select port A */
320 sound_ym.wd_data = sound_ym.rd_data_reg_sel | 0x20; /* strobe H */
321 atari_console_driver.write = atari_par_console_write;
322 }
323 if (atari_console_driver.write && !registered)
324 register_console(&atari_console_driver);
325
326 return 0;
327 }
328
329 early_param("debug", atari_debug_setup);
330