xref: /linux/arch/m68k/atari/debug.c (revision c537b994505099b7197e7d3125b942ecbcc51eb6)
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 
19 #include <asm/atarihw.h>
20 #include <asm/atariints.h>
21 
22 extern char m68k_debug_device[];
23 
24 /* Flag that Modem1 port is already initialized and used */
25 int atari_MFP_init_done;
26 /* Flag that Modem1 port is already initialized and used */
27 int atari_SCC_init_done;
28 /* Can be set somewhere, if a SCC master reset has already be done and should
29  * not be repeated; used by kgdb */
30 int atari_SCC_reset_done;
31 
32 static struct console atari_console_driver = {
33 	.name =		"debug",
34 	.flags =	CON_PRINTBUFFER,
35 	.index =	-1,
36 };
37 
38 
39 static inline void ata_mfp_out (char c)
40 {
41     while (!(mfp.trn_stat & 0x80)) /* wait for tx buf empty */
42 	barrier ();
43     mfp.usart_dta = c;
44 }
45 
46 void atari_mfp_console_write (struct console *co, const char *str,
47 			      unsigned int count)
48 {
49     while (count--) {
50 	if (*str == '\n')
51 	    ata_mfp_out( '\r' );
52 	ata_mfp_out( *str++ );
53     }
54 }
55 
56 static inline void ata_scc_out (char c)
57 {
58     do {
59 	MFPDELAY();
60     } while (!(scc.cha_b_ctrl & 0x04)); /* wait for tx buf empty */
61     MFPDELAY();
62     scc.cha_b_data = c;
63 }
64 
65 void atari_scc_console_write (struct console *co, const char *str,
66 			      unsigned int count)
67 {
68     while (count--) {
69 	if (*str == '\n')
70 	    ata_scc_out( '\r' );
71 	ata_scc_out( *str++ );
72     }
73 }
74 
75 static inline void ata_midi_out (char c)
76 {
77     while (!(acia.mid_ctrl & ACIA_TDRE)) /* wait for tx buf empty */
78 	barrier ();
79     acia.mid_data = c;
80 }
81 
82 void atari_midi_console_write (struct console *co, const char *str,
83 			       unsigned int count)
84 {
85     while (count--) {
86 	if (*str == '\n')
87 	    ata_midi_out( '\r' );
88 	ata_midi_out( *str++ );
89     }
90 }
91 
92 static int ata_par_out (char c)
93 {
94     unsigned char tmp;
95     /* This a some-seconds timeout in case no printer is connected */
96     unsigned long i = loops_per_jiffy > 1 ? loops_per_jiffy : 10000000/HZ;
97 
98     while( (mfp.par_dt_reg & 1) && --i ) /* wait for BUSY == L */
99 	;
100     if (!i) return( 0 );
101 
102     sound_ym.rd_data_reg_sel = 15;  /* select port B */
103     sound_ym.wd_data = c;           /* put char onto port */
104     sound_ym.rd_data_reg_sel = 14;  /* select port A */
105     tmp = sound_ym.rd_data_reg_sel;
106     sound_ym.wd_data = tmp & ~0x20; /* set strobe L */
107     MFPDELAY();                     /* wait a bit */
108     sound_ym.wd_data = tmp | 0x20;  /* set strobe H */
109     return( 1 );
110 }
111 
112 static void atari_par_console_write (struct console *co, const char *str,
113 				     unsigned int count)
114 {
115     static int printer_present = 1;
116 
117     if (!printer_present)
118 	return;
119 
120     while (count--) {
121 	if (*str == '\n')
122 	    if (!ata_par_out( '\r' )) {
123 		printer_present = 0;
124 		return;
125 	    }
126 	if (!ata_par_out( *str++ )) {
127 	    printer_present = 0;
128 	    return;
129 	}
130     }
131 }
132 
133 #ifdef CONFIG_SERIAL_CONSOLE
134 int atari_mfp_console_wait_key(struct console *co)
135 {
136     while( !(mfp.rcv_stat & 0x80) ) /* wait for rx buf filled */
137 	barrier();
138     return( mfp.usart_dta );
139 }
140 
141 int atari_scc_console_wait_key(struct console *co)
142 {
143     do {
144 	MFPDELAY();
145     } while( !(scc.cha_b_ctrl & 0x01) ); /* wait for rx buf filled */
146     MFPDELAY();
147     return( scc.cha_b_data );
148 }
149 
150 int atari_midi_console_wait_key(struct console *co)
151 {
152     while( !(acia.mid_ctrl & ACIA_RDRF) ) /* wait for rx buf filled */
153 	barrier();
154     return( acia.mid_data );
155 }
156 #endif
157 
158 /* The following two functions do a quick'n'dirty initialization of the MFP or
159  * SCC serial ports. They're used by the debugging interface, kgdb, and the
160  * serial console code. */
161 #ifndef CONFIG_SERIAL_CONSOLE
162 static void __init atari_init_mfp_port( int cflag )
163 #else
164 void atari_init_mfp_port( int cflag )
165 #endif
166 {
167     /* timer values for 1200...115200 bps; > 38400 select 110, 134, or 150
168      * bps, resp., and work only correct if there's a RSVE or RSSPEED */
169     static int baud_table[9] = { 16, 11, 8, 4, 2, 1, 175, 143, 128 };
170     int baud = cflag & CBAUD;
171     int parity = (cflag & PARENB) ? ((cflag & PARODD) ? 0x04 : 0x06) : 0;
172     int csize = ((cflag & CSIZE) == CS7) ? 0x20 : 0x00;
173 
174     if (cflag & CBAUDEX)
175 	baud += B38400;
176     if (baud < B1200 || baud > B38400+2)
177 	baud = B9600; /* use default 9600bps for non-implemented rates */
178     baud -= B1200; /* baud_table[] starts at 1200bps */
179 
180     mfp.trn_stat &= ~0x01; /* disable TX */
181     mfp.usart_ctr = parity | csize | 0x88; /* 1:16 clk mode, 1 stop bit */
182     mfp.tim_ct_cd &= 0x70;  /* stop timer D */
183     mfp.tim_dt_d = baud_table[baud];
184     mfp.tim_ct_cd |= 0x01;  /* start timer D, 1:4 */
185     mfp.trn_stat |= 0x01;  /* enable TX */
186 
187     atari_MFP_init_done = 1;
188 }
189 
190 #define SCC_WRITE(reg,val)				\
191     do {						\
192 	scc.cha_b_ctrl = (reg);				\
193 	MFPDELAY();					\
194 	scc.cha_b_ctrl = (val);				\
195 	MFPDELAY();					\
196     } while(0)
197 
198 /* loops_per_jiffy isn't initialized yet, so we can't use udelay(). This does a
199  * delay of ~ 60us. */
200 #define LONG_DELAY()				\
201     do {					\
202 	int i;					\
203 	for( i = 100; i > 0; --i )		\
204 	    MFPDELAY();				\
205     } while(0)
206 
207 #ifndef CONFIG_SERIAL_CONSOLE
208 static void __init atari_init_scc_port( int cflag )
209 #else
210 void atari_init_scc_port( int cflag )
211 #endif
212 {
213     extern int atari_SCC_reset_done;
214     static int clksrc_table[9] =
215 	/* reg 11: 0x50 = BRG, 0x00 = RTxC, 0x28 = TRxC */
216 	{ 0x50, 0x50, 0x50, 0x50, 0x50, 0x50, 0x50, 0x00, 0x00 };
217     static int brgsrc_table[9] =
218 	/* reg 14: 0 = RTxC, 2 = PCLK */
219 	{ 2, 2, 2, 2, 2, 2, 0, 2, 2 };
220     static int clkmode_table[9] =
221 	/* reg 4: 0x40 = x16, 0x80 = x32, 0xc0 = x64 */
222 	{ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0xc0, 0x80 };
223     static int div_table[9] =
224 	/* reg12 (BRG low) */
225 	{ 208, 138, 103, 50, 24, 11, 1, 0, 0 };
226 
227     int baud = cflag & CBAUD;
228     int clksrc, clkmode, div, reg3, reg5;
229 
230     if (cflag & CBAUDEX)
231 	baud += B38400;
232     if (baud < B1200 || baud > B38400+2)
233 	baud = B9600; /* use default 9600bps for non-implemented rates */
234     baud -= B1200; /* tables starts at 1200bps */
235 
236     clksrc  = clksrc_table[baud];
237     clkmode = clkmode_table[baud];
238     div     = div_table[baud];
239     if (ATARIHW_PRESENT(TT_MFP) && baud >= 6) {
240 	/* special treatment for TT, where rates >= 38400 are done via TRxC */
241 	clksrc = 0x28; /* TRxC */
242 	clkmode = baud == 6 ? 0xc0 :
243 		  baud == 7 ? 0x80 : /* really 76800bps */
244 			      0x40;  /* really 153600bps */
245 	div = 0;
246     }
247 
248     reg3 = (cflag & CSIZE) == CS8 ? 0xc0 : 0x40;
249     reg5 = (cflag & CSIZE) == CS8 ? 0x60 : 0x20 | 0x82 /* assert DTR/RTS */;
250 
251     (void)scc.cha_b_ctrl;	/* reset reg pointer */
252     SCC_WRITE( 9, 0xc0 );	/* reset */
253     LONG_DELAY();		/* extra delay after WR9 access */
254     SCC_WRITE( 4, (cflag & PARENB) ? ((cflag & PARODD) ? 0x01 : 0x03) : 0 |
255 		  0x04 /* 1 stopbit */ |
256 		  clkmode );
257     SCC_WRITE( 3, reg3 );
258     SCC_WRITE( 5, reg5 );
259     SCC_WRITE( 9, 0 );		/* no interrupts */
260     LONG_DELAY();		/* extra delay after WR9 access */
261     SCC_WRITE( 10, 0 );		/* NRZ mode */
262     SCC_WRITE( 11, clksrc );	/* main clock source */
263     SCC_WRITE( 12, div );	/* BRG value */
264     SCC_WRITE( 13, 0 );		/* BRG high byte */
265     SCC_WRITE( 14, brgsrc_table[baud] );
266     SCC_WRITE( 14, brgsrc_table[baud] | (div ? 1 : 0) );
267     SCC_WRITE( 3, reg3 | 1 );
268     SCC_WRITE( 5, reg5 | 8 );
269 
270     atari_SCC_reset_done = 1;
271     atari_SCC_init_done = 1;
272 }
273 
274 #ifndef CONFIG_SERIAL_CONSOLE
275 static void __init atari_init_midi_port( int cflag )
276 #else
277 void atari_init_midi_port( int cflag )
278 #endif
279 {
280     int baud = cflag & CBAUD;
281     int csize = ((cflag & CSIZE) == CS8) ? 0x10 : 0x00;
282     /* warning 7N1 isn't possible! (instead 7O2 is used...) */
283     int parity = (cflag & PARENB) ? ((cflag & PARODD) ? 0x0c : 0x08) : 0x04;
284     int div;
285 
286     /* 4800 selects 7812.5, 115200 selects 500000, all other (incl. 9600 as
287      * default) the standard MIDI speed 31250. */
288     if (cflag & CBAUDEX)
289 	baud += B38400;
290     if (baud == B4800)
291 	div = ACIA_DIV64; /* really 7812.5 bps */
292     else if (baud == B38400+2 /* 115200 */)
293 	div = ACIA_DIV1; /* really 500 kbps (does that work??) */
294     else
295 	div = ACIA_DIV16; /* 31250 bps, standard for MIDI */
296 
297     /* RTS low, ints disabled */
298     acia.mid_ctrl = div | csize | parity |
299 		    ((atari_switches & ATARI_SWITCH_MIDI) ?
300 		     ACIA_RHTID : ACIA_RLTID);
301 }
302 
303 void __init atari_debug_init(void)
304 {
305     if (!strcmp( m68k_debug_device, "ser" )) {
306 	/* defaults to ser2 for a Falcon and ser1 otherwise */
307 	strcpy( m68k_debug_device, MACH_IS_FALCON ? "ser2" : "ser1" );
308 
309     }
310 
311     if (!strcmp( m68k_debug_device, "ser1" )) {
312 	/* ST-MFP Modem1 serial port */
313 	atari_init_mfp_port( B9600|CS8 );
314 	atari_console_driver.write = atari_mfp_console_write;
315     }
316     else if (!strcmp( m68k_debug_device, "ser2" )) {
317 	/* SCC Modem2 serial port */
318 	atari_init_scc_port( B9600|CS8 );
319 	atari_console_driver.write = atari_scc_console_write;
320     }
321     else if (!strcmp( m68k_debug_device, "midi" )) {
322 	/* MIDI port */
323 	atari_init_midi_port( B9600|CS8 );
324 	atari_console_driver.write = atari_midi_console_write;
325     }
326     else if (!strcmp( m68k_debug_device, "par" )) {
327 	/* parallel printer */
328 	atari_turnoff_irq( IRQ_MFP_BUSY ); /* avoid ints */
329 	sound_ym.rd_data_reg_sel = 7;  /* select mixer control */
330 	sound_ym.wd_data = 0xff;       /* sound off, ports are output */
331 	sound_ym.rd_data_reg_sel = 15; /* select port B */
332 	sound_ym.wd_data = 0;          /* no char */
333 	sound_ym.rd_data_reg_sel = 14; /* select port A */
334 	sound_ym.wd_data = sound_ym.rd_data_reg_sel | 0x20; /* strobe H */
335 	atari_console_driver.write = atari_par_console_write;
336     }
337     if (atari_console_driver.write)
338 	register_console(&atari_console_driver);
339 }
340 
341 /*
342  * Local variables:
343  *  c-indent-level: 4
344  *  tab-width: 8
345  * End:
346  */
347