blob: a50760fea4016ab8f8b3911712bf452cbbe1e725 [file] [log] [blame]
Wolfgang Denk70a20472005-09-25 15:59:01 +02001/*
2 * Most of this taken from Redboot hal_platform_setup.h with cleanup
3 *
4 * NOTE: I haven't clean this up considerably, just enough to get it
5 * running. See hal_platform_setup.h for the source. See
Marcel Ziswiler2a4741d2007-10-19 00:25:33 +02006 * board/cradle/lowlevel_init.S for another PXA250 setup that is
Wolfgang Denk70a20472005-09-25 15:59:01 +02007 * much cleaner.
8 *
9 * See file CREDITS for list of people who contributed to this
10 * project.
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License as
14 * published by the Free Software Foundation; either version 2 of
15 * the License, or (at your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
25 * MA 02111-1307 USA
26 */
27
28#include <config.h>
29#include <version.h>
30#include <asm/arch/pxa-regs.h>
31
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +020032DRAM_SIZE: .long CONFIG_SYS_DRAM_SIZE
Wolfgang Denk70a20472005-09-25 15:59:01 +020033
34/* wait for coprocessor write complete */
35 .macro CPWAIT reg
36 mrc p15,0,\reg,c2,c0,0
37 mov \reg,\reg
38 sub pc,pc,#4
39 .endm
40
41/*
Wolfgang Denk53677ef2008-05-20 16:00:29 +020042 * Memory setup
Wolfgang Denk70a20472005-09-25 15:59:01 +020043 */
Marcel Ziswiler2a4741d2007-10-19 00:25:33 +020044.globl lowlevel_init
45lowlevel_init:
Wolfgang Denk70a20472005-09-25 15:59:01 +020046
47 mov r10, lr
48
49#ifdef DEBUG_BLINK_ENABLE
50 /* 3rd blink */
51 bl blink
52#endif
53
54 /* Set up GPIO pins first ----------------------------------------- */
55 ldr r0, =GPSR0
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +020056 ldr r1, =CONFIG_SYS_GPSR0_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +020057 str r1, [r0]
58
59 ldr r0, =GPSR1
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +020060 ldr r1, =CONFIG_SYS_GPSR1_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +020061 str r1, [r0]
62
63 ldr r0, =GPSR2
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +020064 ldr r1, =CONFIG_SYS_GPSR2_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +020065 str r1, [r0]
66
67 ldr r0, =GPCR0
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +020068 ldr r1, =CONFIG_SYS_GPCR0_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +020069 str r1, [r0]
70
71 ldr r0, =GPCR1
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +020072 ldr r1, =CONFIG_SYS_GPCR1_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +020073 str r1, [r0]
74
75 ldr r0, =GPCR2
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +020076 ldr r1, =CONFIG_SYS_GPCR2_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +020077 str r1, [r0]
78
79 ldr r0, =GPDR0
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +020080 ldr r1, =CONFIG_SYS_GPDR0_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +020081 str r1, [r0]
82
83 ldr r0, =GPDR1
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +020084 ldr r1, =CONFIG_SYS_GPDR1_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +020085 str r1, [r0]
86
87 ldr r0, =GPDR2
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +020088 ldr r1, =CONFIG_SYS_GPDR2_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +020089 str r1, [r0]
90
91 ldr r0, =GAFR0_L
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +020092 ldr r1, =CONFIG_SYS_GAFR0_L_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +020093 str r1, [r0]
94
95 ldr r0, =GAFR0_U
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +020096 ldr r1, =CONFIG_SYS_GAFR0_U_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +020097 str r1, [r0]
98
99 ldr r0, =GAFR1_L
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200100 ldr r1, =CONFIG_SYS_GAFR1_L_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200101 str r1, [r0]
102
103 ldr r0, =GAFR1_U
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200104 ldr r1, =CONFIG_SYS_GAFR1_U_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200105 str r1, [r0]
106
107 ldr r0, =GAFR2_L
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200108 ldr r1, =CONFIG_SYS_GAFR2_L_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200109 str r1, [r0]
110
111 ldr r0, =GAFR2_U
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200112 ldr r1, =CONFIG_SYS_GAFR2_U_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200113 str r1, [r0]
114
115 ldr r0, =PSSR /* enable GPIO pins */
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200116 ldr r1, =CONFIG_SYS_PSSR_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200117 str r1, [r0]
118
119#ifdef DEBUG_BLINK_ENABLE
120 /* 4th debug blink */
Wolfgang Denk53677ef2008-05-20 16:00:29 +0200121 bl blink
Wolfgang Denk70a20472005-09-25 15:59:01 +0200122#endif
123
124 /* ---------------------------------------------------------------- */
125 /* Enable memory interface */
126 /* */
127 /* The sequence below is based on the recommended init steps */
128 /* detailed in the Intel PXA250 Operating Systems Developers Guide, */
129 /* Chapter 10. */
130 /* ---------------------------------------------------------------- */
131
132 /* ---------------------------------------------------------------- */
133 /* Step 1: Wait for at least 200 microsedonds to allow internal */
134 /* clocks to settle. Only necessary after hard reset... */
135 /* FIXME: can be optimized later */
136 /* ---------------------------------------------------------------- */
137
138 ldr r3, =OSCR /* reset the OS Timer Count to zero */
139 mov r2, #0
140 str r2, [r3]
141 ldr r4, =0x300 /* really 0x2E1 is about 200usec, */
142 /* so 0x300 should be plenty */
1431:
144 ldr r2, [r3]
145 cmp r4, r2
146 bgt 1b
147
148mem_init:
149
150 ldr r1, =MEMC_BASE /* get memory controller base addr. */
151
152 /* ---------------------------------------------------------------- */
153 /* Step 2a: Initialize Asynchronous static memory controller */
154 /* ---------------------------------------------------------------- */
155
156 /* MSC registers: timing, bus width, mem type */
157
158 /* MSC0: nCS(0,1) */
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200159 ldr r2, =CONFIG_SYS_MSC0_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200160 str r2, [r1, #MSC0_OFFSET]
161 ldr r2, [r1, #MSC0_OFFSET] /* read back to ensure */
162 /* that data latches */
163 /* MSC1: nCS(2,3) */
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200164 ldr r2, =CONFIG_SYS_MSC1_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200165 str r2, [r1, #MSC1_OFFSET]
166 ldr r2, [r1, #MSC1_OFFSET]
167
168 /* MSC2: nCS(4,5) */
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200169 ldr r2, =CONFIG_SYS_MSC2_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200170 str r2, [r1, #MSC2_OFFSET]
171 ldr r2, [r1, #MSC2_OFFSET]
172
173 /* ---------------------------------------------------------------- */
174 /* Step 2b: Initialize Card Interface */
175 /* ---------------------------------------------------------------- */
176
177 /* MECR: Memory Expansion Card Register */
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200178 ldr r2, =CONFIG_SYS_MECR_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200179 str r2, [r1, #MECR_OFFSET]
180 ldr r2, [r1, #MECR_OFFSET]
181
182 /* MCMEM0: Card Interface slot 0 timing */
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200183 ldr r2, =CONFIG_SYS_MCMEM0_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200184 str r2, [r1, #MCMEM0_OFFSET]
185 ldr r2, [r1, #MCMEM0_OFFSET]
186
187 /* MCMEM1: Card Interface slot 1 timing */
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200188 ldr r2, =CONFIG_SYS_MCMEM1_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200189 str r2, [r1, #MCMEM1_OFFSET]
190 ldr r2, [r1, #MCMEM1_OFFSET]
191
192 /* MCATT0: Card Interface Attribute Space Timing, slot 0 */
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200193 ldr r2, =CONFIG_SYS_MCATT0_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200194 str r2, [r1, #MCATT0_OFFSET]
195 ldr r2, [r1, #MCATT0_OFFSET]
196
197 /* MCATT1: Card Interface Attribute Space Timing, slot 1 */
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200198 ldr r2, =CONFIG_SYS_MCATT1_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200199 str r2, [r1, #MCATT1_OFFSET]
200 ldr r2, [r1, #MCATT1_OFFSET]
201
202 /* MCIO0: Card Interface I/O Space Timing, slot 0 */
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200203 ldr r2, =CONFIG_SYS_MCIO0_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200204 str r2, [r1, #MCIO0_OFFSET]
205 ldr r2, [r1, #MCIO0_OFFSET]
206
207 /* MCIO1: Card Interface I/O Space Timing, slot 1 */
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200208 ldr r2, =CONFIG_SYS_MCIO1_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200209 str r2, [r1, #MCIO1_OFFSET]
210 ldr r2, [r1, #MCIO1_OFFSET]
211
212#ifdef DEBUG_BLINK_ENABLE
213 /* 5th blink */
Wolfgang Denk53677ef2008-05-20 16:00:29 +0200214 bl blink
Wolfgang Denk70a20472005-09-25 15:59:01 +0200215#endif
216
217 /* ---------------------------------------------------------------- */
218 /* Step 2c: Write FLYCNFG FIXME: what's that??? */
219 /* ---------------------------------------------------------------- */
220
221 /* ---------------------------------------------------------------- */
222 /* Step 2d: Initialize Timing for Sync Memory (SDCLK0) */
223 /* ---------------------------------------------------------------- */
224
225 /* Before accessing MDREFR we need a valid DRI field, so we set */
226 /* this to power on defaults + DRI field. */
227
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200228 ldr r3, =CONFIG_SYS_MDREFR_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200229 ldr r2, =0xFFF
230 and r3, r3, r2
231 ldr r4, =0x03ca4000
232 orr r4, r4, r3
233 str r4, [r1, #MDREFR_OFFSET] /* write back MDREFR */
234 ldr r4, [r1, #MDREFR_OFFSET]
235
236 /* Note: preserve the mdrefr value in r4 */
237
238 /* ---------------------------------------------------------------- */
239 /* Step 3: Initialize Synchronous Static Memory (Flash/Peripherals) */
240 /* ---------------------------------------------------------------- */
241
242 /* Initialize SXCNFG register. Assert the enable bits */
243
244 /* Write SXMRS to cause an MRS command to all enabled banks of */
245 /* synchronous static memory. Note that SXLCR need not be written */
246 /* at this time. */
247
248 /* FIXME: we use async mode for now */
249
250 /* ---------------------------------------------------------------- */
251 /* Step 4: Initialize SDRAM */
252 /* ---------------------------------------------------------------- */
253
254 /* set MDREFR according to user define with exception of a few bits */
255
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200256 ldr r4, =CONFIG_SYS_MDREFR_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200257 orr r4, r4, #(MDREFR_SLFRSH)
258 bic r4, r4, #(MDREFR_E1PIN|MDREFR_E0PIN)
259 str r4, [r1, #MDREFR_OFFSET] /* write back MDREFR */
260 ldr r4, [r1, #MDREFR_OFFSET]
261
262 /* Step 4b: de-assert MDREFR:SLFRSH. */
263
264 bic r4, r4, #(MDREFR_SLFRSH)
265 str r4, [r1, #MDREFR_OFFSET] /* write back MDREFR */
266 ldr r4, [r1, #MDREFR_OFFSET]
267
268 /* Step 4c: assert MDREFR:E1PIN and E0PIO as desired */
269
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200270 ldr r4, =CONFIG_SYS_MDREFR_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200271 str r4, [r1, #MDREFR_OFFSET] /* write back MDREFR */
272 ldr r4, [r1, #MDREFR_OFFSET]
273
274
275 /* Step 4d: write MDCNFG with MDCNFG:DEx deasserted (set to 0), to */
276 /* configure but not enable each SDRAM partition pair. */
277
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200278 ldr r4, =CONFIG_SYS_MDCNFG_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200279 bic r4, r4, #(MDCNFG_DE0|MDCNFG_DE1)
280
281 str r4, [r1, #MDCNFG_OFFSET] /* write back MDCNFG */
282 ldr r4, [r1, #MDCNFG_OFFSET]
283
284 /* Step 4e: Wait for the clock to the SDRAMs to stabilize, */
285 /* 100..200 µsec. */
286
287 ldr r3, =OSCR /* reset the OS Timer Count to zero */
288 mov r2, #0
289 str r2, [r3]
290 ldr r4, =0x300 /* really 0x2E1 is about 200usec, */
291 /* so 0x300 should be plenty */
2921:
293 ldr r2, [r3]
294 cmp r4, r2
295 bgt 1b
296
297 /* Step 4f: Trigger a number (usually 8) refresh cycles by */
298 /* attempting non-burst read or write accesses to disabled */
299 /* SDRAM, as commonly specified in the power up sequence */
300 /* documented in SDRAM data sheets. The address(es) used */
301 /* for this purpose must not be cacheable. */
302
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200303 ldr r3, =CONFIG_SYS_DRAM_BASE
Wolfgang Denk70a20472005-09-25 15:59:01 +0200304 str r2, [r3]
305 str r2, [r3]
306 str r2, [r3]
307 str r2, [r3]
308 str r2, [r3]
309 str r2, [r3]
310 str r2, [r3]
311 str r2, [r3]
312
313 /* Step 4g: Write MDCNFG with enable bits asserted */
314 /* (MDCNFG:DEx set to 1). */
315
316 ldr r3, [r1, #MDCNFG_OFFSET]
317 orr r3, r3, #(MDCNFG_DE0|MDCNFG_DE1)
318 str r3, [r1, #MDCNFG_OFFSET]
319
320 /* Step 4h: Write MDMRS. */
321
Jean-Christophe PLAGNIOL-VILLARD6d0f6bc2008-10-16 15:01:15 +0200322 ldr r2, =CONFIG_SYS_MDMRS_VAL
Wolfgang Denk70a20472005-09-25 15:59:01 +0200323 str r2, [r1, #MDMRS_OFFSET]
324
325 /* We are finished with Intel's memory controller initialisation */
326#if 0
327 /* FIXME turn on serial ports */
328 /* look into moving this to board_init() */
Wolfgang Denk53677ef2008-05-20 16:00:29 +0200329 ldr r2, =(PXA_CS5_PHYS + 0x03C0002c)
Wolfgang Denk70a20472005-09-25 15:59:01 +0200330 mov r3, #0x13
331 str r3, [r2]
332#endif
333
334#ifdef DEBUG_BLINK_ENABLE
335 /* 6th blink */
Wolfgang Denk53677ef2008-05-20 16:00:29 +0200336 bl blink
Wolfgang Denk70a20472005-09-25 15:59:01 +0200337#endif
338
339 /* ---------------------------------------------------------------- */
340 /* Disable (mask) all interrupts at interrupt controller */
341 /* ---------------------------------------------------------------- */
342
343initirqs:
344
345 mov r1, #0 /* clear int. level register (IRQ, not FIQ) */
346 ldr r2, =ICLR
347 str r1, [r2]
348
349 ldr r2, =ICMR /* mask all interrupts at the controller */
350 str r1, [r2]
351
352 /* ---------------------------------------------------------------- */
353 /* Clock initialisation */
354 /* ---------------------------------------------------------------- */
355
356initclks:
357
358 /* Disable the peripheral clocks, and set the core clock frequency */
359 /* (hard-coding at 398.12MHz for now). */
360
361 /* Turn Off ALL on-chip peripheral clocks for re-configuration */
362 /* Note: See label 'ENABLECLKS' for the re-enabling */
363#if 0
364 ldr r1, =CKEN
365 mov r2, #0
366 str r2, [r1]
367
368 /* default value in case no valid rotary switch setting is found */
369 ldr r2, =(CCCR_L27|CCCR_M2|CCCR_N10) /* DEFAULT: {200/200/100} */
370
371 /* ... and write the core clock config register */
372 ldr r1, =CCCR
373 str r2, [r1]
374
375#endif
376
377#ifdef RTC
378 /* enable the 32Khz oscillator for RTC and PowerManager */
379
380 ldr r1, =OSCC
381 mov r2, #OSCC_OON
382 str r2, [r1]
383
384 /* NOTE: spin here until OSCC.OOK get set, meaning the PLL */
385 /* has settled. */
38660:
387 ldr r2, [r1]
388 ands r2, r2, #1
389 beq 60b
390#endif
391
392 /* ---------------------------------------------------------------- */
393 /* */
394 /* ---------------------------------------------------------------- */
395
396 /* Save SDRAM size */
397 ldr r1, =DRAM_SIZE
Marcel Ziswiler2a4741d2007-10-19 00:25:33 +0200398 str r8, [r1]
Wolfgang Denk70a20472005-09-25 15:59:01 +0200399
400 /* Interrupt init: Mask all interrupts */
401 ldr r0, =ICMR /* enable no sources */
402 mov r1, #0
403 str r1, [r0]
404
405 /* FIXME */
406
407#define NODEBUG
408#ifdef NODEBUG
409 /*Disable software and data breakpoints */
410 mov r0,#0
411 mcr p15,0,r0,c14,c8,0 /* ibcr0 */
412 mcr p15,0,r0,c14,c9,0 /* ibcr1 */
413 mcr p15,0,r0,c14,c4,0 /* dbcon */
414
415 /*Enable all debug functionality */
416 mov r0,#0x80000000
417 mcr p14,0,r0,c10,c0,0 /* dcsr */
418#endif
419
420 /* ---------------------------------------------------------------- */
421 /* End memsetup */
422 /* ---------------------------------------------------------------- */
423
424#ifdef DEBUG_BLINK_ENABLE
425 /* 7th blink */
Wolfgang Denk53677ef2008-05-20 16:00:29 +0200426 bl blink
Wolfgang Denk70a20472005-09-25 15:59:01 +0200427#endif
428
Marcel Ziswiler2a4741d2007-10-19 00:25:33 +0200429endlowlevel_init:
Wolfgang Denk70a20472005-09-25 15:59:01 +0200430
431 mov pc, r10
432
433
434#ifdef DEBUG_BLINK_ENABLE
435
436/* debug LED code */
437
438/* delay about 200ms */
439delay:
440
441 /* reset OSCR to 0 */
442 ldr r8, =OSCR
443 mov r9, #0
444 str r9, [r8]
445
446 /* make sure new value has stuck */
4471:
448 ldr r8, =OSCR
449 ldr r9, [r8]
450 mov r8, #0x10000
451 cmp r9, r8
452 bgt 1b
453
454 /* now, wait for delay to expire */
4551:
456 ldr r8, =OSCR
457 ldr r9, [r8]
458 mov r8, #0xd4000
459 cmp r8, r9
460 bgt 1b
461
462 mov pc, lr
463
464/* blink code -- trashes r7, r8, r9 */
465
466.globl blink
467blink:
468
469 mov r7, lr
470
471 /* set GPIO10 as outout */
472 ldr r8, =GPDR0
473 ldr r9, [r8]
474 orr r9, r9, #(1<<10)
475 str r9, [r8]
476
477 /* turn LED off */
478 mov r9, #(1<<10)
479 ldr r8, =GPCR0
480 str r9, [r8]
481 bl delay
482
483 /* turn LED on */
484 mov r9, #(1<<10)
485 ldr r8, =GPSR0
486 str r9, [r8]
487 bl delay
488
489 /* turn LED off */
490 mov r9, #(1<<10)
491 ldr r8, =GPCR0
492 str r9, [r8]
493
494 mov pc, r7
495
496#endif