fuzev2: prevent button light flickering when accessing µSD
[kugel-rb.git] / firmware / target / sh / system-sh.c
blobe054801b5715da46f0f121d01d8a00051202f0d0
1 /***************************************************************************
2 * __________ __ ___.
3 * Open \______ \ ____ ____ | | _\_ |__ _______ ___
4 * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
5 * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
6 * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
7 * \/ \/ \/ \/ \/
8 * $Id$
10 * Copyright (C) 2007 by Jens Arnold
11 * Based on the work of Alan Korr and others
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * as published by the Free Software Foundation; either version 2
16 * of the License, or (at your option) any later version.
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
21 ****************************************************************************/
23 #include <stdio.h>
24 #include "config.h"
25 #include "system.h"
26 #include "lcd.h"
27 #include "font.h"
28 #include "led.h"
30 const unsigned bit_n_table[32] = {
31 1LU<< 0, 1LU<< 1, 1LU<< 2, 1LU<< 3,
32 1LU<< 4, 1LU<< 5, 1LU<< 6, 1LU<< 7,
33 1LU<< 8, 1LU<< 9, 1LU<<10, 1LU<<11,
34 1LU<<12, 1LU<<13, 1LU<<14, 1LU<<15,
35 1LU<<16, 1LU<<17, 1LU<<18, 1LU<<19,
36 1LU<<20, 1LU<<21, 1LU<<22, 1LU<<23,
37 1LU<<24, 1LU<<25, 1LU<<26, 1LU<<27,
38 1LU<<28, 1LU<<29, 1LU<<30, 1LU<<31
41 static const char* const irqname[] = {
42 "", "", "", "", "IllInstr", "", "IllSltIn","","",
43 "CPUAdrEr", "DMAAdrEr", "NMI", "UserBrk",
44 "","","","","","","","","","","","","","","","","","","",
45 "Trap32","Trap33","Trap34","Trap35","Trap36","Trap37","Trap38","Trap39",
46 "Trap40","Trap41","Trap42","Trap43","Trap44","Trap45","Trap46","Trap47",
47 "Trap48","Trap49","Trap50","Trap51","Trap52","Trap53","Trap54","Trap55",
48 "Trap56","Trap57","Trap58","Trap59","Trap60","Trap61","Trap62","Trap63",
49 "Irq0","Irq1","Irq2","Irq3","Irq4","Irq5","Irq6","Irq7",
50 "Dma0","","Dma1","","Dma2","","Dma3","",
51 "IMIA0","IMIB0","OVI0","", "IMIA1","IMIB1","OVI1","",
52 "IMIA2","IMIB2","OVI2","", "IMIA3","IMIB3","OVI3","",
53 "IMIA4","IMIB4","OVI4","",
54 "Ser0Err","Ser0Rx","Ser0Tx","Ser0TE",
55 "Ser1Err","Ser1Rx","Ser1Tx","Ser1TE",
56 "ParityEr","A/D conv","","","Watchdog","DRAMRefr"
59 #define RESERVE_INTERRUPT(number) "\t.long\t_UIE" #number "\n"
60 #define DEFAULT_INTERRUPT(name, number) "\t.weak\t_" #name \
61 "\n\t.set\t_" #name ",_UIE" #number \
62 "\n\t.long\t_" #name "\n"
64 asm (
66 /* Vector table.
67 * Handled in asm because gcc 4.x doesn't allow weak aliases to symbols
68 * defined in an asm block -- silly.
69 * Reset vectors (0..3) are handled in crt0.S */
71 ".section\t.vectors,\"aw\",@progbits\n"
72 DEFAULT_INTERRUPT (GII, 4)
73 RESERVE_INTERRUPT ( 5)
74 DEFAULT_INTERRUPT (ISI, 6)
75 RESERVE_INTERRUPT ( 7)
76 RESERVE_INTERRUPT ( 8)
77 DEFAULT_INTERRUPT (CPUAE, 9)
78 DEFAULT_INTERRUPT (DMAAE, 10)
79 DEFAULT_INTERRUPT (NMI, 11)
80 DEFAULT_INTERRUPT (UB, 12)
81 RESERVE_INTERRUPT ( 13)
82 RESERVE_INTERRUPT ( 14)
83 RESERVE_INTERRUPT ( 15)
84 RESERVE_INTERRUPT ( 16) /* TCB #0 */
85 RESERVE_INTERRUPT ( 17) /* TCB #1 */
86 RESERVE_INTERRUPT ( 18) /* TCB #2 */
87 RESERVE_INTERRUPT ( 19) /* TCB #3 */
88 RESERVE_INTERRUPT ( 20) /* TCB #4 */
89 RESERVE_INTERRUPT ( 21) /* TCB #5 */
90 RESERVE_INTERRUPT ( 22) /* TCB #6 */
91 RESERVE_INTERRUPT ( 23) /* TCB #7 */
92 RESERVE_INTERRUPT ( 24) /* TCB #8 */
93 RESERVE_INTERRUPT ( 25) /* TCB #9 */
94 RESERVE_INTERRUPT ( 26) /* TCB #10 */
95 RESERVE_INTERRUPT ( 27) /* TCB #11 */
96 RESERVE_INTERRUPT ( 28) /* TCB #12 */
97 RESERVE_INTERRUPT ( 29) /* TCB #13 */
98 RESERVE_INTERRUPT ( 30) /* TCB #14 */
99 RESERVE_INTERRUPT ( 31) /* TCB #15 */
100 DEFAULT_INTERRUPT (TRAPA32, 32)
101 DEFAULT_INTERRUPT (TRAPA33, 33)
102 DEFAULT_INTERRUPT (TRAPA34, 34)
103 DEFAULT_INTERRUPT (TRAPA35, 35)
104 DEFAULT_INTERRUPT (TRAPA36, 36)
105 DEFAULT_INTERRUPT (TRAPA37, 37)
106 DEFAULT_INTERRUPT (TRAPA38, 38)
107 DEFAULT_INTERRUPT (TRAPA39, 39)
108 DEFAULT_INTERRUPT (TRAPA40, 40)
109 DEFAULT_INTERRUPT (TRAPA41, 41)
110 DEFAULT_INTERRUPT (TRAPA42, 42)
111 DEFAULT_INTERRUPT (TRAPA43, 43)
112 DEFAULT_INTERRUPT (TRAPA44, 44)
113 DEFAULT_INTERRUPT (TRAPA45, 45)
114 DEFAULT_INTERRUPT (TRAPA46, 46)
115 DEFAULT_INTERRUPT (TRAPA47, 47)
116 DEFAULT_INTERRUPT (TRAPA48, 48)
117 DEFAULT_INTERRUPT (TRAPA49, 49)
118 DEFAULT_INTERRUPT (TRAPA50, 50)
119 DEFAULT_INTERRUPT (TRAPA51, 51)
120 DEFAULT_INTERRUPT (TRAPA52, 52)
121 DEFAULT_INTERRUPT (TRAPA53, 53)
122 DEFAULT_INTERRUPT (TRAPA54, 54)
123 DEFAULT_INTERRUPT (TRAPA55, 55)
124 DEFAULT_INTERRUPT (TRAPA56, 56)
125 DEFAULT_INTERRUPT (TRAPA57, 57)
126 DEFAULT_INTERRUPT (TRAPA58, 58)
127 DEFAULT_INTERRUPT (TRAPA59, 59)
128 DEFAULT_INTERRUPT (TRAPA60, 60)
129 DEFAULT_INTERRUPT (TRAPA61, 61)
130 DEFAULT_INTERRUPT (TRAPA62, 62)
131 DEFAULT_INTERRUPT (TRAPA63, 63)
132 DEFAULT_INTERRUPT (IRQ0, 64)
133 DEFAULT_INTERRUPT (IRQ1, 65)
134 DEFAULT_INTERRUPT (IRQ2, 66)
135 DEFAULT_INTERRUPT (IRQ3, 67)
136 DEFAULT_INTERRUPT (IRQ4, 68)
137 DEFAULT_INTERRUPT (IRQ5, 69)
138 DEFAULT_INTERRUPT (IRQ6, 70)
139 DEFAULT_INTERRUPT (IRQ7, 71)
140 DEFAULT_INTERRUPT (DEI0, 72)
141 RESERVE_INTERRUPT ( 73)
142 DEFAULT_INTERRUPT (DEI1, 74)
143 RESERVE_INTERRUPT ( 75)
144 DEFAULT_INTERRUPT (DEI2, 76)
145 RESERVE_INTERRUPT ( 77)
146 DEFAULT_INTERRUPT (DEI3, 78)
147 RESERVE_INTERRUPT ( 79)
148 DEFAULT_INTERRUPT (IMIA0, 80)
149 DEFAULT_INTERRUPT (IMIB0, 81)
150 DEFAULT_INTERRUPT (OVI0, 82)
151 RESERVE_INTERRUPT ( 83)
152 DEFAULT_INTERRUPT (IMIA1, 84)
153 DEFAULT_INTERRUPT (IMIB1, 85)
154 DEFAULT_INTERRUPT (OVI1, 86)
155 RESERVE_INTERRUPT ( 87)
156 DEFAULT_INTERRUPT (IMIA2, 88)
157 DEFAULT_INTERRUPT (IMIB2, 89)
158 DEFAULT_INTERRUPT (OVI2, 90)
159 RESERVE_INTERRUPT ( 91)
160 DEFAULT_INTERRUPT (IMIA3, 92)
161 DEFAULT_INTERRUPT (IMIB3, 93)
162 DEFAULT_INTERRUPT (OVI3, 94)
163 RESERVE_INTERRUPT ( 95)
164 DEFAULT_INTERRUPT (IMIA4, 96)
165 DEFAULT_INTERRUPT (IMIB4, 97)
166 DEFAULT_INTERRUPT (OVI4, 98)
167 RESERVE_INTERRUPT ( 99)
168 DEFAULT_INTERRUPT (REI0, 100)
169 DEFAULT_INTERRUPT (RXI0, 101)
170 DEFAULT_INTERRUPT (TXI0, 102)
171 DEFAULT_INTERRUPT (TEI0, 103)
172 DEFAULT_INTERRUPT (REI1, 104)
173 DEFAULT_INTERRUPT (RXI1, 105)
174 DEFAULT_INTERRUPT (TXI1, 106)
175 DEFAULT_INTERRUPT (TEI1, 107)
176 RESERVE_INTERRUPT ( 108)
177 DEFAULT_INTERRUPT (ADITI, 109)
179 /* UIE# block.
180 * Must go into the same section as the UIE() handler */
182 "\t.text\n"
183 "_UIE4:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
184 "_UIE5:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
185 "_UIE6:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
186 "_UIE7:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
187 "_UIE8:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
188 "_UIE9:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
189 "_UIE10:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
190 "_UIE11:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
191 "_UIE12:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
192 "_UIE13:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
193 "_UIE14:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
194 "_UIE15:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
195 "_UIE16:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
196 "_UIE17:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
197 "_UIE18:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
198 "_UIE19:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
199 "_UIE20:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
200 "_UIE21:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
201 "_UIE22:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
202 "_UIE23:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
203 "_UIE24:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
204 "_UIE25:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
205 "_UIE26:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
206 "_UIE27:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
207 "_UIE28:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
208 "_UIE29:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
209 "_UIE30:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
210 "_UIE31:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
211 "_UIE32:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
212 "_UIE33:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
213 "_UIE34:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
214 "_UIE35:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
215 "_UIE36:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
216 "_UIE37:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
217 "_UIE38:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
218 "_UIE39:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
219 "_UIE40:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
220 "_UIE41:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
221 "_UIE42:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
222 "_UIE43:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
223 "_UIE44:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
224 "_UIE45:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
225 "_UIE46:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
226 "_UIE47:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
227 "_UIE48:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
228 "_UIE49:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
229 "_UIE50:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
230 "_UIE51:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
231 "_UIE52:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
232 "_UIE53:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
233 "_UIE54:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
234 "_UIE55:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
235 "_UIE56:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
236 "_UIE57:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
237 "_UIE58:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
238 "_UIE59:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
239 "_UIE60:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
240 "_UIE61:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
241 "_UIE62:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
242 "_UIE63:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
243 "_UIE64:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
244 "_UIE65:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
245 "_UIE66:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
246 "_UIE67:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
247 "_UIE68:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
248 "_UIE69:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
249 "_UIE70:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
250 "_UIE71:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
251 "_UIE72:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
252 "_UIE73:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
253 "_UIE74:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
254 "_UIE75:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
255 "_UIE76:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
256 "_UIE77:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
257 "_UIE78:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
258 "_UIE79:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
259 "_UIE80:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
260 "_UIE81:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
261 "_UIE82:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
262 "_UIE83:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
263 "_UIE84:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
264 "_UIE85:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
265 "_UIE86:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
266 "_UIE87:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
267 "_UIE88:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
268 "_UIE89:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
269 "_UIE90:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
270 "_UIE91:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
271 "_UIE92:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
272 "_UIE93:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
273 "_UIE94:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
274 "_UIE95:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
275 "_UIE96:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
276 "_UIE97:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
277 "_UIE98:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
278 "_UIE99:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
279 "_UIE100:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
280 "_UIE101:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
281 "_UIE102:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
282 "_UIE103:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
283 "_UIE104:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
284 "_UIE105:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
285 "_UIE106:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
286 "_UIE107:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
287 "_UIE108:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
288 "_UIE109:\tbsr\t_UIE\n\tmov.l\t@r15+,r4\n"
292 extern void UIE4(void); /* needed for calculating the UIE number */
294 void UIE (unsigned int pc) __attribute__((section(".text")));
295 void UIE (unsigned int pc) /* Unexpected Interrupt or Exception */
297 unsigned int n;
299 asm volatile ("sts\tpr,%0" : "=r"(n));
301 /* clear screen */
302 #ifdef HAVE_LCD_BITMAP
303 #if LCD_DEPTH > 1
304 lcd_set_backdrop(NULL);
305 lcd_set_drawmode(DRMODE_SOLID);
306 lcd_set_foreground(LCD_BLACK);
307 lcd_set_background(LCD_WHITE);
308 #endif
309 lcd_setfont(FONT_SYSFIXED);
310 lcd_set_viewport(NULL);
311 #endif
313 lcd_clear_display();
314 /* output exception */
315 n = (n - (unsigned)UIE4 + 12)>>2; /* get exception or interrupt number */
316 lcd_putsf(0, 0, "I%02x:%s", n, irqname[n]);
317 lcd_putsf(0, 1, "at %08x", pc);
318 lcd_update();
320 /* try to restart firmware if ON is pressed */
321 system_exception_wait();
323 /* enable the watchguard timer, but don't service it */
324 RSTCSR_W = 0x5a40; /* Reset enabled, power-on reset */
325 TCSR_W = 0xa560; /* Watchdog timer mode, timer enabled, sysclk/2 */
326 while (1);
329 void system_init(void)
331 /* Disable all interrupts */
332 IPRA = 0;
333 IPRB = 0;
334 IPRC = 0;
335 IPRD = 0;
336 IPRE = 0;
338 /* NMI level low, falling edge on all interrupts */
339 ICR = 0;
341 /* Enable burst and RAS down mode on DRAM */
342 DCR |= 0x5000;
344 /* Activate Warp mode (simultaneous internal and external mem access) */
345 BCR |= 0x2000;
347 /* Bus state controller initializations. These are only necessary when
348 running from flash. */
349 WCR1 = 0x40FD; /* Long wait states for CS6 (ATA), short for the rest. */
350 WCR3 = 0x8000; /* WAIT is pulled up, 1 state inserted for CS6 */
353 void system_reboot (void)
355 disable_irq();
357 asm volatile ("ldc\t%0,vbr" : : "r"(0));
359 PACR2 |= 0x4000; /* for coldstart detection */
360 IPRA = 0;
361 IPRB = 0;
362 IPRC = 0;
363 IPRD = 0;
364 IPRE = 0;
365 ICR = 0;
367 asm volatile ("jmp @%0; mov.l @%1,r15" : :
368 "r"(*(int*)0),"r"(4));
371 void system_exception_wait(void)
373 #if (CONFIG_LED == LED_REAL)
374 bool state = false;
375 int i = 0;
376 #endif
378 while (1)
380 #if (CONFIG_LED == LED_REAL)
381 if (--i <= 0)
383 state = !state;
384 led(state);
385 i = 240000;
387 #endif
389 #if CONFIG_KEYPAD == PLAYER_PAD
390 /* Player */
391 if (!(PADRL & 0x20))
392 #elif CONFIG_KEYPAD == RECORDER_PAD
393 /* Recorder */
394 #ifdef HAVE_FMADC
395 if (!(PCDR & 0x0008))
396 #else
397 if (!(PBDRH & 0x01))
398 #endif
399 #elif CONFIG_KEYPAD == ONDIO_PAD
400 /* Ondio */
401 if (!(PCDR & 0x0008))
402 #endif /* CONFIG_KEYPAD */
403 return;
407 /* Utilise the user break controller to catch invalid memory accesses. */
408 int system_memory_guard(int newmode)
410 static const struct {
411 unsigned long addr;
412 unsigned long mask;
413 unsigned short bbr;
414 } modes[MAXMEMGUARD] = {
415 /* catch nothing */
416 { 0x00000000, 0x00000000, 0x0000 },
417 /* catch writes to area 02 (flash ROM) */
418 { 0x02000000, 0x00FFFFFF, 0x00F8 },
419 /* catch all accesses to areas 00 (internal ROM) and 01 (free) */
420 { 0x00000000, 0x01FFFFFF, 0x00FC }
423 int oldmode = MEMGUARD_NONE;
424 int i;
426 /* figure out the old mode from what is in the UBC regs. If the register
427 values don't match any mode, assume MEMGUARD_NONE */
428 for (i = MEMGUARD_NONE; i < MAXMEMGUARD; i++)
430 if (BAR == modes[i].addr && BAMR == modes[i].mask &&
431 BBR == modes[i].bbr)
433 oldmode = i;
434 break;
438 if (newmode == MEMGUARD_KEEP)
439 newmode = oldmode;
441 BBR = 0; /* switch off everything first */
443 /* always set the UBC according to the mode, in case the old settings
444 didn't match any valid mode */
445 BAR = modes[newmode].addr;
446 BAMR = modes[newmode].mask;
447 BBR = modes[newmode].bbr;
449 return oldmode;