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/config.h>
18#include <linux/types.h>
19#include <linux/sched.h>
20#include <linux/tty.h>
21#include <linux/console.h>
22#include <linux/init.h>
23#include <linux/delay.h>
24
25#define BOOTINFO_COMPAT_1_0
26#include <asm/setup.h>
27#include <asm/bootinfo.h>
28#include <asm/machw.h>
29#include <asm/macints.h>
30
31extern char m68k_debug_device[];
32
33extern struct compat_bootinfo compat_boot_info;
34
35extern unsigned long mac_videobase;
36extern unsigned long mac_videodepth;
37extern unsigned long mac_rowbytes;
38
39extern void mac_serial_print(const char *);
40
41#define DEBUG_HEADS
42#undef DEBUG_SCREEN
43#define DEBUG_SERIAL
44
45/*
46 * These two auxiliary debug functions should go away ASAP. Only usage:
47 * before the console output is up (after head.S come some other crucial
48 * setup routines :-) it permits writing 'data' to the screen as bit patterns
49 * (good luck reading those). Helped to figure that the bootinfo contained
50 * garbage data on the amount and size of memory chunks ...
51 *
52 * The 'pos' argument now simply means 'linefeed after print' ...
53 */
54
55#ifdef DEBUG_SCREEN
56static int peng=0, line=0;
57#endif
58
59void mac_debugging_short(int pos, short num)
60{
61#ifdef DEBUG_SCREEN
62	unsigned char *pengoffset;
63	unsigned char *pptr;
64	int i;
65#endif
66
67#ifdef DEBUG_SERIAL
68	printk("debug: %d !\n", num);
69#endif
70
71#ifdef DEBUG_SCREEN
72	if (!MACH_IS_MAC) {
73		/* printk("debug: %d !\n", num); */
74		return;
75	}
76
77	/* calculate current offset */
78	pengoffset=(unsigned char *)(mac_videobase+(150+line*2)*mac_rowbytes)
79		    +80*peng;
80
81	pptr=pengoffset;
82
83	for(i=0;i<8*sizeof(short);i++) /* # of bits */
84	{
85		/*        value        mask for bit i, reverse order */
86		*pptr++ = (num & ( 1 << (8*sizeof(short)-i-1) ) ? 0xFF : 0x00);
87	}
88
89	peng++;
90
91	if (pos) {
92		line++;
93		peng = 0;
94	}
95#endif
96}
97
98void mac_debugging_long(int pos, long addr)
99{
100#ifdef DEBUG_SCREEN
101	unsigned char *pengoffset;
102	unsigned char *pptr;
103	int i;
104#endif
105
106#ifdef DEBUG_SERIAL
107	printk("debug: #%ld !\n", addr);
108#endif
109
110#ifdef DEBUG_SCREEN
111	if (!MACH_IS_MAC) {
112		/* printk("debug: #%ld !\n", addr); */
113		return;
114	}
115
116	pengoffset=(unsigned char *)(mac_videobase+(150+line*2)*mac_rowbytes)
117		    +80*peng;
118
119	pptr=pengoffset;
120
121	for(i=0;i<8*sizeof(long);i++) /* # of bits */
122	{
123		*pptr++ = (addr & ( 1 << (8*sizeof(long)-i-1) ) ? 0xFF : 0x00);
124	}
125
126	peng++;
127
128	if (pos) {
129		line++;
130		peng = 0;
131	}
132#endif
133}
134
135#ifdef DEBUG_SERIAL
136/*
137 * TODO: serial debug code
138 */
139
140struct mac_SCC
141 {
142  u_char cha_b_ctrl;
143  u_char char_dummy1;
144  u_char cha_a_ctrl;
145  u_char char_dummy2;
146  u_char cha_b_data;
147  u_char char_dummy3;
148  u_char cha_a_data;
149 };
150
151# define scc (*((volatile struct mac_SCC*)mac_bi_data.sccbase))
152
153/* Flag that serial port is already initialized and used */
154int mac_SCC_init_done = 0;
155/* Can be set somewhere, if a SCC master reset has already be done and should
156 * not be repeated; used by kgdb */
157int mac_SCC_reset_done = 0;
158
159static int scc_port = -1;
160
161static struct console mac_console_driver = {
162	name:		"debug",
163	flags:		CON_PRINTBUFFER,
164	index:		-1,
165};
166
167/*
168 * Crude hack to get console output to the screen before the framebuffer
169 * is initialized (happens a lot later in 2.1!).
170 * We just use the console routines declared in head.S, this will interfere
171 * with regular framebuffer console output and should be used exclusively
172 * to debug kernel problems manifesting before framebuffer init (aka WSOD)
173 *
174 * To keep this hack from interfering with the regular console driver, either
175 * deregister this driver before/on framebuffer console init, or silence this
176 * function after the fbcon driver is running (will lose console messages!?).
177 * To debug real early bugs, need to write a 'mac_register_console_hack()'
178 * that is called from start_kernel() before setup_arch() and just registers
179 * this driver if Mac.
180 */
181
182void mac_debug_console_write (struct console *co, const char *str,
183			      unsigned int count)
184{
185	mac_serial_print(str);
186}
187
188
189
190/* Mac: loops_per_jiffy min. 19000 ^= .5 us; MFPDELAY was 0.6 us*/
191
192#define uSEC 1
193
194static inline void mac_sccb_out (char c)
195{
196    int i;
197    do {
198	for( i = uSEC; i > 0; --i )
199		barrier();
200    } while (!(scc.cha_b_ctrl & 0x04)); /* wait for tx buf empty */
201    for( i = uSEC; i > 0; --i )
202	barrier();
203    scc.cha_b_data = c;
204}
205
206static inline void mac_scca_out (char c)
207{
208    int i;
209    do {
210	for( i = uSEC; i > 0; --i )
211		barrier();
212    } while (!(scc.cha_a_ctrl & 0x04)); /* wait for tx buf empty */
213    for( i = uSEC; i > 0; --i )
214	barrier();
215    scc.cha_a_data = c;
216}
217
218void mac_sccb_console_write (struct console *co, const char *str,
219			      unsigned int count)
220{
221    while (count--) {
222	if (*str == '\n')
223	    mac_sccb_out( '\r' );
224	mac_sccb_out( *str++ );
225    }
226}
227
228void mac_scca_console_write (struct console *co, const char *str,
229			      unsigned int count)
230{
231    while (count--) {
232	if (*str == '\n')
233	    mac_scca_out( '\r' );
234	mac_scca_out( *str++ );
235    }
236}
237
238/* The following two functions do a quick'n'dirty initialization of the MFP or
239 * SCC serial ports. They're used by the debugging interface, kgdb, and the
240 * serial console code. */
241#define SCCB_WRITE(reg,val)				\
242    do {						\
243	int i;						\
244	scc.cha_b_ctrl = (reg);				\
245	for( i = uSEC; i > 0; --i )			\
246		barrier();				\
247	scc.cha_b_ctrl = (val);				\
248	for( i = uSEC; i > 0; --i )			\
249		barrier();				\
250    } while(0)
251
252#define SCCA_WRITE(reg,val)				\
253    do {						\
254	int i;						\
255	scc.cha_a_ctrl = (reg);				\
256	for( i = uSEC; i > 0; --i )			\
257		barrier();				\
258	scc.cha_a_ctrl = (val);				\
259	for( i = uSEC; i > 0; --i )			\
260		barrier();				\
261    } while(0)
262
263/* loops_per_jiffy isn't initialized yet, so we can't use udelay(). This does a
264 * delay of ~ 60us. */
265/* Mac: loops_per_jiffy min. 19000 ^= .5 us; MFPDELAY was 0.6 us*/
266#define LONG_DELAY()				\
267    do {					\
268	int i;					\
269	for( i = 60*uSEC; i > 0; --i )		\
270	    barrier();				\
271    } while(0)
272
273#ifndef CONFIG_SERIAL_CONSOLE
274static void __init mac_init_scc_port( int cflag, int port )
275#else
276void mac_init_scc_port( int cflag, int port )
277#endif
278{
279	extern int mac_SCC_reset_done;
280
281	/*
282	 * baud rates: 1200, 1800, 2400, 4800, 9600, 19.2k, 38.4k, 57.6k, 115.2k
283	 */
284
285	static int clksrc_table[9] =
286		/* reg 11: 0x50 = BRG, 0x00 = RTxC, 0x28 = TRxC */
287    		{ 0x50, 0x50, 0x50, 0x50, 0x50, 0x50, 0x50, 0x00, 0x00 };
288	static int clkmode_table[9] =
289		/* reg 4: 0x40 = x16, 0x80 = x32, 0xc0 = x64 */
290    		{ 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0xc0, 0x80 };
291	static int div_table[9] =
292		/* reg12 (BRG low) */
293    		{ 94, 62, 46, 22, 10, 4, 1, 0, 0 };
294
295    int baud = cflag & CBAUD;
296    int clksrc, clkmode, div, reg3, reg5;
297
298    if (cflag & CBAUDEX)
299	baud += B38400;
300    if (baud < B1200 || baud > B38400+2)
301	baud = B9600; /* use default 9600bps for non-implemented rates */
302    baud -= B1200; /* tables starts at 1200bps */
303
304    clksrc  = clksrc_table[baud];
305    clkmode = clkmode_table[baud];
306    div     = div_table[baud];
307
308    reg3 = (((cflag & CSIZE) == CS8) ? 0xc0 : 0x40);
309    reg5 = (((cflag & CSIZE) == CS8) ? 0x60 : 0x20) | 0x82 /* assert DTR/RTS */;
310
311    if (port == 1) {
312	    (void)scc.cha_b_ctrl;	/* reset reg pointer */
313	    SCCB_WRITE( 9, 0xc0 );	/* reset */
314	    LONG_DELAY();		/* extra delay after WR9 access */
315	    SCCB_WRITE( 4, (cflag & PARENB) ? ((cflag & PARODD) ? 0x01 : 0x03) : 0 |
316			  0x04 /* 1 stopbit */ |
317			  clkmode );
318	    SCCB_WRITE( 3, reg3 );
319	    SCCB_WRITE( 5, reg5 );
320	    SCCB_WRITE( 9, 0 );		/* no interrupts */
321	    LONG_DELAY();		/* extra delay after WR9 access */
322	    SCCB_WRITE( 10, 0 );	/* NRZ mode */
323	    SCCB_WRITE( 11, clksrc );	/* main clock source */
324	    SCCB_WRITE( 12, div );	/* BRG value */
325	    SCCB_WRITE( 13, 0 );		/* BRG high byte */
326	    SCCB_WRITE( 14, 1 );
327	    SCCB_WRITE( 3, reg3 | 1 );
328	    SCCB_WRITE( 5, reg5 | 8 );
329    } else if (port == 0) {
330	    (void)scc.cha_a_ctrl;	/* reset reg pointer */
331	    SCCA_WRITE( 9, 0xc0 );	/* reset */
332	    LONG_DELAY();		/* extra delay after WR9 access */
333	    SCCA_WRITE( 4, (cflag & PARENB) ? ((cflag & PARODD) ? 0x01 : 0x03) : 0 |
334			  0x04 /* 1 stopbit */ |
335			  clkmode );
336	    SCCA_WRITE( 3, reg3 );
337	    SCCA_WRITE( 5, reg5 );
338	    SCCA_WRITE( 9, 0 );		/* no interrupts */
339	    LONG_DELAY();		/* extra delay after WR9 access */
340	    SCCA_WRITE( 10, 0 );	/* NRZ mode */
341	    SCCA_WRITE( 11, clksrc );	/* main clock source */
342	    SCCA_WRITE( 12, div );	/* BRG value */
343	    SCCA_WRITE( 13, 0 );		/* BRG high byte */
344	    SCCA_WRITE( 14, 1 );
345	    SCCA_WRITE( 3, reg3 | 1 );
346	    SCCA_WRITE( 5, reg5 | 8 );
347    }
348
349    mac_SCC_reset_done = 1;
350    mac_SCC_init_done = 1;
351}
352#endif /* DEBUG_SERIAL */
353
354void mac_init_scca_port( int cflag )
355{
356	mac_init_scc_port(cflag, 0);
357}
358
359void mac_init_sccb_port( int cflag )
360{
361	mac_init_scc_port(cflag, 1);
362}
363
364void __init mac_debug_init(void)
365{
366#ifdef DEBUG_SERIAL
367    if (   !strcmp( m68k_debug_device, "ser"  )
368        || !strcmp( m68k_debug_device, "ser1" )) {
369	/* Mac modem port */
370	mac_init_scc_port( B9600|CS8, 0 );
371	mac_console_driver.write = mac_scca_console_write;
372	scc_port = 0;
373    }
374    else if (!strcmp( m68k_debug_device, "ser2" )) {
375	/* Mac printer port */
376	mac_init_scc_port( B9600|CS8, 1 );
377	mac_console_driver.write = mac_sccb_console_write;
378	scc_port = 1;
379    }
380#endif
381#ifdef DEBUG_HEADS
382    if (   !strcmp( m68k_debug_device, "scn"  )
383        || !strcmp( m68k_debug_device, "con" )) {
384	/* display, using head.S console routines */
385	mac_console_driver.write = mac_debug_console_write;
386    }
387#endif
388    if (mac_console_driver.write)
389	register_console(&mac_console_driver);
390}
391
392/*
393 * Local variables:
394 *  c-indent-level: 4
395 *  tab-width: 8
396 * End:
397 */
398