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1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * This file contains miscellaneous low-level functions.
4 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
5 *
6 * Largely rewritten by Cort Dougan (cort@cs.nmt.edu)
7 * and Paul Mackerras.
8 * Adapted for iSeries by Mike Corrigan (mikejc@us.ibm.com)
9 * PPC64 updates by Dave Engebretsen (engebret@us.ibm.com)
10 */
11
12#include <linux/linkage.h>
13#include <linux/sys.h>
14#include <asm/unistd.h>
15#include <asm/errno.h>
16#include <asm/processor.h>
17#include <asm/page.h>
18#include <asm/cache.h>
19#include <asm/ppc_asm.h>
20#include <asm/asm-offsets.h>
21#include <asm/cputable.h>
22#include <asm/thread_info.h>
23#include <asm/kexec.h>
24#include <asm/ptrace.h>
25#include <asm/mmu.h>
26#include <asm/export.h>
27#include <asm/feature-fixups.h>
28
29 .text
30
31_GLOBAL(__bswapdi2)
32EXPORT_SYMBOL(__bswapdi2)
33 srdi r8,r3,32
34 rlwinm r7,r3,8,0xffffffff
35 rlwimi r7,r3,24,0,7
36 rlwinm r9,r8,8,0xffffffff
37 rlwimi r7,r3,24,16,23
38 rlwimi r9,r8,24,0,7
39 rlwimi r9,r8,24,16,23
40 sldi r7,r7,32
41 or r3,r7,r9
42 blr
43
44
45#ifdef CONFIG_PPC_EARLY_DEBUG_BOOTX
46_GLOBAL(rmci_on)
47 sync
48 isync
49 li r3,0x100
50 rldicl r3,r3,32,0
51 mfspr r5,SPRN_HID4
52 or r5,r5,r3
53 sync
54 mtspr SPRN_HID4,r5
55 isync
56 slbia
57 isync
58 sync
59 blr
60
61_GLOBAL(rmci_off)
62 sync
63 isync
64 li r3,0x100
65 rldicl r3,r3,32,0
66 mfspr r5,SPRN_HID4
67 andc r5,r5,r3
68 sync
69 mtspr SPRN_HID4,r5
70 isync
71 slbia
72 isync
73 sync
74 blr
75#endif /* CONFIG_PPC_EARLY_DEBUG_BOOTX */
76
77#if defined(CONFIG_PPC_PMAC) || defined(CONFIG_PPC_MAPLE)
78
79/*
80 * Do an IO access in real mode
81 */
82_GLOBAL(real_readb)
83 mfmsr r7
84 ori r0,r7,MSR_DR
85 xori r0,r0,MSR_DR
86 sync
87 mtmsrd r0
88 sync
89 isync
90 mfspr r6,SPRN_HID4
91 rldicl r5,r6,32,0
92 ori r5,r5,0x100
93 rldicl r5,r5,32,0
94 sync
95 mtspr SPRN_HID4,r5
96 isync
97 slbia
98 isync
99 lbz r3,0(r3)
100 sync
101 mtspr SPRN_HID4,r6
102 isync
103 slbia
104 isync
105 mtmsrd r7
106 sync
107 isync
108 blr
109
110 /*
111 * Do an IO access in real mode
112 */
113_GLOBAL(real_writeb)
114 mfmsr r7
115 ori r0,r7,MSR_DR
116 xori r0,r0,MSR_DR
117 sync
118 mtmsrd r0
119 sync
120 isync
121 mfspr r6,SPRN_HID4
122 rldicl r5,r6,32,0
123 ori r5,r5,0x100
124 rldicl r5,r5,32,0
125 sync
126 mtspr SPRN_HID4,r5
127 isync
128 slbia
129 isync
130 stb r3,0(r4)
131 sync
132 mtspr SPRN_HID4,r6
133 isync
134 slbia
135 isync
136 mtmsrd r7
137 sync
138 isync
139 blr
140#endif /* defined(CONFIG_PPC_PMAC) || defined(CONFIG_PPC_MAPLE) */
141
142#ifdef CONFIG_PPC_PASEMI
143
144_GLOBAL(real_205_readb)
145 mfmsr r7
146 ori r0,r7,MSR_DR
147 xori r0,r0,MSR_DR
148 sync
149 mtmsrd r0
150 sync
151 isync
152 LBZCIX(R3,R0,R3)
153 isync
154 mtmsrd r7
155 sync
156 isync
157 blr
158
159_GLOBAL(real_205_writeb)
160 mfmsr r7
161 ori r0,r7,MSR_DR
162 xori r0,r0,MSR_DR
163 sync
164 mtmsrd r0
165 sync
166 isync
167 STBCIX(R3,R0,R4)
168 isync
169 mtmsrd r7
170 sync
171 isync
172 blr
173
174#endif /* CONFIG_PPC_PASEMI */
175
176
177#if defined(CONFIG_CPU_FREQ_PMAC64) || defined(CONFIG_CPU_FREQ_MAPLE)
178/*
179 * SCOM access functions for 970 (FX only for now)
180 *
181 * unsigned long scom970_read(unsigned int address);
182 * void scom970_write(unsigned int address, unsigned long value);
183 *
184 * The address passed in is the 24 bits register address. This code
185 * is 970 specific and will not check the status bits, so you should
186 * know what you are doing.
187 */
188_GLOBAL(scom970_read)
189 /* interrupts off */
190 mfmsr r4
191 ori r0,r4,MSR_EE
192 xori r0,r0,MSR_EE
193 mtmsrd r0,1
194
195 /* rotate 24 bits SCOM address 8 bits left and mask out it's low 8 bits
196 * (including parity). On current CPUs they must be 0'd,
197 * and finally or in RW bit
198 */
199 rlwinm r3,r3,8,0,15
200 ori r3,r3,0x8000
201
202 /* do the actual scom read */
203 sync
204 mtspr SPRN_SCOMC,r3
205 isync
206 mfspr r3,SPRN_SCOMD
207 isync
208 mfspr r0,SPRN_SCOMC
209 isync
210
211 /* XXX: fixup result on some buggy 970's (ouch ! we lost a bit, bah
212 * that's the best we can do). Not implemented yet as we don't use
213 * the scom on any of the bogus CPUs yet, but may have to be done
214 * ultimately
215 */
216
217 /* restore interrupts */
218 mtmsrd r4,1
219 blr
220
221
222_GLOBAL(scom970_write)
223 /* interrupts off */
224 mfmsr r5
225 ori r0,r5,MSR_EE
226 xori r0,r0,MSR_EE
227 mtmsrd r0,1
228
229 /* rotate 24 bits SCOM address 8 bits left and mask out it's low 8 bits
230 * (including parity). On current CPUs they must be 0'd.
231 */
232
233 rlwinm r3,r3,8,0,15
234
235 sync
236 mtspr SPRN_SCOMD,r4 /* write data */
237 isync
238 mtspr SPRN_SCOMC,r3 /* write command */
239 isync
240 mfspr 3,SPRN_SCOMC
241 isync
242
243 /* restore interrupts */
244 mtmsrd r5,1
245 blr
246#endif /* CONFIG_CPU_FREQ_PMAC64 || CONFIG_CPU_FREQ_MAPLE */
247
248/* kexec_wait(phys_cpu)
249 *
250 * wait for the flag to change, indicating this kernel is going away but
251 * the slave code for the next one is at addresses 0 to 100.
252 *
253 * This is used by all slaves, even those that did not find a matching
254 * paca in the secondary startup code.
255 *
256 * Physical (hardware) cpu id should be in r3.
257 */
258_GLOBAL(kexec_wait)
259 bcl 20,31,$+4
2601: mflr r5
261 addi r5,r5,kexec_flag-1b
262
26399: HMT_LOW
264#ifdef CONFIG_KEXEC_CORE /* use no memory without kexec */
265 lwz r4,0(r5)
266 cmpwi 0,r4,0
267 beq 99b
268#ifdef CONFIG_PPC_BOOK3S_64
269 li r10,0x60
270 mfmsr r11
271 clrrdi r11,r11,1 /* Clear MSR_LE */
272 mtsrr0 r10
273 mtsrr1 r11
274 rfid
275#else
276 /* Create TLB entry in book3e_secondary_core_init */
277 li r4,0
278 ba 0x60
279#endif
280#endif
281
282/* this can be in text because we won't change it until we are
283 * running in real anyways
284 */
285kexec_flag:
286 .long 0
287
288
289#ifdef CONFIG_KEXEC_CORE
290#ifdef CONFIG_PPC_BOOK3E_64
291/*
292 * BOOK3E has no real MMU mode, so we have to setup the initial TLB
293 * for a core to identity map v:0 to p:0. This current implementation
294 * assumes that 1G is enough for kexec.
295 */
296kexec_create_tlb:
297 /*
298 * Invalidate all non-IPROT TLB entries to avoid any TLB conflict.
299 * IPROT TLB entries should be >= PAGE_OFFSET and thus not conflict.
300 */
301 PPC_TLBILX_ALL(0,R0)
302 sync
303 isync
304
305 mfspr r10,SPRN_TLB1CFG
306 andi. r10,r10,TLBnCFG_N_ENTRY /* Extract # entries */
307 subi r10,r10,1 /* Last entry: no conflict with kernel text */
308 lis r9,MAS0_TLBSEL(1)@h
309 rlwimi r9,r10,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r9) */
310
311/* Set up a temp identity mapping v:0 to p:0 and return to it. */
312 mtspr SPRN_MAS0,r9
313
314 lis r9,(MAS1_VALID|MAS1_IPROT)@h
315 ori r9,r9,(MAS1_TSIZE(BOOK3E_PAGESZ_1GB))@l
316 mtspr SPRN_MAS1,r9
317
318 LOAD_REG_IMMEDIATE(r9, 0x0 | MAS2_M_IF_NEEDED)
319 mtspr SPRN_MAS2,r9
320
321 LOAD_REG_IMMEDIATE(r9, 0x0 | MAS3_SR | MAS3_SW | MAS3_SX)
322 mtspr SPRN_MAS3,r9
323 li r9,0
324 mtspr SPRN_MAS7,r9
325
326 tlbwe
327 isync
328 blr
329#endif
330
331/* kexec_smp_wait(void)
332 *
333 * call with interrupts off
334 * note: this is a terminal routine, it does not save lr
335 *
336 * get phys id from paca
337 * switch to real mode
338 * mark the paca as no longer used
339 * join other cpus in kexec_wait(phys_id)
340 */
341_GLOBAL(kexec_smp_wait)
342 lhz r3,PACAHWCPUID(r13)
343 bl real_mode
344
345 li r4,KEXEC_STATE_REAL_MODE
346 stb r4,PACAKEXECSTATE(r13)
347
348 b kexec_wait
349
350/*
351 * switch to real mode (turn mmu off)
352 * we use the early kernel trick that the hardware ignores bits
353 * 0 and 1 (big endian) of the effective address in real mode
354 *
355 * don't overwrite r3 here, it is live for kexec_wait above.
356 */
357SYM_FUNC_START_LOCAL(real_mode) /* assume normal blr return */
358#ifdef CONFIG_PPC_BOOK3E_64
359 /* Create an identity mapping. */
360 b kexec_create_tlb
361#else
3621: li r9,MSR_RI
363 li r10,MSR_DR|MSR_IR
364 mflr r11 /* return address to SRR0 */
365 mfmsr r12
366 andc r9,r12,r9
367 andc r10,r12,r10
368
369 mtmsrd r9,1
370 mtspr SPRN_SRR1,r10
371 mtspr SPRN_SRR0,r11
372 rfid
373#endif
374SYM_FUNC_END(real_mode)
375
376/*
377 * kexec_sequence(newstack, start, image, control, clear_all(),
378 copy_with_mmu_off)
379 *
380 * does the grungy work with stack switching and real mode switches
381 * also does simple calls to other code
382 */
383
384_GLOBAL(kexec_sequence)
385 mflr r0
386 std r0,16(r1)
387
388 /* switch stacks to newstack -- &kexec_stack.stack */
389 stdu r1,THREAD_SIZE-STACK_FRAME_MIN_SIZE(r3)
390 mr r1,r3
391
392 li r0,0
393 std r0,16(r1)
394
395 /* save regs for local vars on new stack.
396 * yes, we won't go back, but ...
397 */
398 std r31,-8(r1)
399 std r30,-16(r1)
400 std r29,-24(r1)
401 std r28,-32(r1)
402 std r27,-40(r1)
403 std r26,-48(r1)
404 std r25,-56(r1)
405
406 stdu r1,-STACK_FRAME_MIN_SIZE-64(r1)
407
408 /* save args into preserved regs */
409 mr r31,r3 /* newstack (both) */
410 mr r30,r4 /* start (real) */
411 mr r29,r5 /* image (virt) */
412 mr r28,r6 /* control, unused */
413 mr r27,r7 /* clear_all() fn desc */
414 mr r26,r8 /* copy_with_mmu_off */
415 lhz r25,PACAHWCPUID(r13) /* get our phys cpu from paca */
416
417 /* disable interrupts, we are overwriting kernel data next */
418#ifdef CONFIG_PPC_BOOK3E_64
419 wrteei 0
420#else
421 mfmsr r3
422 rlwinm r3,r3,0,17,15
423 mtmsrd r3,1
424#endif
425
426 /* We need to turn the MMU off unless we are in hash mode
427 * under a hypervisor
428 */
429 cmpdi r26,0
430 beq 1f
431 bl real_mode
4321:
433 /* copy dest pages, flush whole dest image */
434 mr r3,r29
435 bl kexec_copy_flush /* (image) */
436
437 /* turn off mmu now if not done earlier */
438 cmpdi r26,0
439 bne 1f
440 bl real_mode
441
442 /* copy 0x100 bytes starting at start to 0 */
4431: li r3,0
444 mr r4,r30 /* start, aka phys mem offset */
445 li r5,0x100
446 li r6,0
447 bl copy_and_flush /* (dest, src, copy limit, start offset) */
4481: /* assume normal blr return */
449
450 /* release other cpus to the new kernel secondary start at 0x60 */
451 mflr r5
452 li r6,1
453 stw r6,kexec_flag-1b(5)
454
455 cmpdi r27,0
456 beq 1f
457
458 /* clear out hardware hash page table and tlb */
459#ifdef CONFIG_PPC64_ELF_ABI_V1
460 ld r12,0(r27) /* deref function descriptor */
461#else
462 mr r12,r27
463#endif
464 mtctr r12
465 bctrl /* mmu_hash_ops.hpte_clear_all(void); */
466
467/*
468 * kexec image calling is:
469 * the first 0x100 bytes of the entry point are copied to 0
470 *
471 * all slaves branch to slave = 0x60 (absolute)
472 * slave(phys_cpu_id);
473 *
474 * master goes to start = entry point
475 * start(phys_cpu_id, start, 0);
476 *
477 *
478 * a wrapper is needed to call existing kernels, here is an approximate
479 * description of one method:
480 *
481 * v2: (2.6.10)
482 * start will be near the boot_block (maybe 0x100 bytes before it?)
483 * it will have a 0x60, which will b to boot_block, where it will wait
484 * and 0 will store phys into struct boot-block and load r3 from there,
485 * copy kernel 0-0x100 and tell slaves to back down to 0x60 again
486 *
487 * v1: (2.6.9)
488 * boot block will have all cpus scanning device tree to see if they
489 * are the boot cpu ?????
490 * other device tree differences (prop sizes, va vs pa, etc)...
491 */
4921: mr r3,r25 # my phys cpu
493 mr r4,r30 # start, aka phys mem offset
494 mtlr 4
495 li r5,0
496 blr /* image->start(physid, image->start, 0); */
497#endif /* CONFIG_KEXEC_CORE */
1/*
2 * This file contains miscellaneous low-level functions.
3 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
4 *
5 * Largely rewritten by Cort Dougan (cort@cs.nmt.edu)
6 * and Paul Mackerras.
7 * Adapted for iSeries by Mike Corrigan (mikejc@us.ibm.com)
8 * PPC64 updates by Dave Engebretsen (engebret@us.ibm.com)
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
14 *
15 */
16
17#include <linux/sys.h>
18#include <asm/unistd.h>
19#include <asm/errno.h>
20#include <asm/processor.h>
21#include <asm/page.h>
22#include <asm/cache.h>
23#include <asm/ppc_asm.h>
24#include <asm/asm-offsets.h>
25#include <asm/cputable.h>
26#include <asm/thread_info.h>
27#include <asm/kexec.h>
28#include <asm/ptrace.h>
29
30 .text
31
32_GLOBAL(call_do_softirq)
33 mflr r0
34 std r0,16(r1)
35 stdu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3)
36 mr r1,r3
37 bl .__do_softirq
38 ld r1,0(r1)
39 ld r0,16(r1)
40 mtlr r0
41 blr
42
43_GLOBAL(call_handle_irq)
44 ld r8,0(r6)
45 mflr r0
46 std r0,16(r1)
47 mtctr r8
48 stdu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r5)
49 mr r1,r5
50 bctrl
51 ld r1,0(r1)
52 ld r0,16(r1)
53 mtlr r0
54 blr
55
56 .section ".toc","aw"
57PPC64_CACHES:
58 .tc ppc64_caches[TC],ppc64_caches
59 .section ".text"
60
61/*
62 * Write any modified data cache blocks out to memory
63 * and invalidate the corresponding instruction cache blocks.
64 *
65 * flush_icache_range(unsigned long start, unsigned long stop)
66 *
67 * flush all bytes from start through stop-1 inclusive
68 */
69
70_KPROBE(__flush_icache_range)
71
72/*
73 * Flush the data cache to memory
74 *
75 * Different systems have different cache line sizes
76 * and in some cases i-cache and d-cache line sizes differ from
77 * each other.
78 */
79 ld r10,PPC64_CACHES@toc(r2)
80 lwz r7,DCACHEL1LINESIZE(r10)/* Get cache line size */
81 addi r5,r7,-1
82 andc r6,r3,r5 /* round low to line bdy */
83 subf r8,r6,r4 /* compute length */
84 add r8,r8,r5 /* ensure we get enough */
85 lwz r9,DCACHEL1LOGLINESIZE(r10) /* Get log-2 of cache line size */
86 srw. r8,r8,r9 /* compute line count */
87 beqlr /* nothing to do? */
88 mtctr r8
891: dcbst 0,r6
90 add r6,r6,r7
91 bdnz 1b
92 sync
93
94/* Now invalidate the instruction cache */
95
96 lwz r7,ICACHEL1LINESIZE(r10) /* Get Icache line size */
97 addi r5,r7,-1
98 andc r6,r3,r5 /* round low to line bdy */
99 subf r8,r6,r4 /* compute length */
100 add r8,r8,r5
101 lwz r9,ICACHEL1LOGLINESIZE(r10) /* Get log-2 of Icache line size */
102 srw. r8,r8,r9 /* compute line count */
103 beqlr /* nothing to do? */
104 mtctr r8
1052: icbi 0,r6
106 add r6,r6,r7
107 bdnz 2b
108 isync
109 blr
110 .previous .text
111/*
112 * Like above, but only do the D-cache.
113 *
114 * flush_dcache_range(unsigned long start, unsigned long stop)
115 *
116 * flush all bytes from start to stop-1 inclusive
117 */
118_GLOBAL(flush_dcache_range)
119
120/*
121 * Flush the data cache to memory
122 *
123 * Different systems have different cache line sizes
124 */
125 ld r10,PPC64_CACHES@toc(r2)
126 lwz r7,DCACHEL1LINESIZE(r10) /* Get dcache line size */
127 addi r5,r7,-1
128 andc r6,r3,r5 /* round low to line bdy */
129 subf r8,r6,r4 /* compute length */
130 add r8,r8,r5 /* ensure we get enough */
131 lwz r9,DCACHEL1LOGLINESIZE(r10) /* Get log-2 of dcache line size */
132 srw. r8,r8,r9 /* compute line count */
133 beqlr /* nothing to do? */
134 mtctr r8
1350: dcbst 0,r6
136 add r6,r6,r7
137 bdnz 0b
138 sync
139 blr
140
141/*
142 * Like above, but works on non-mapped physical addresses.
143 * Use only for non-LPAR setups ! It also assumes real mode
144 * is cacheable. Used for flushing out the DART before using
145 * it as uncacheable memory
146 *
147 * flush_dcache_phys_range(unsigned long start, unsigned long stop)
148 *
149 * flush all bytes from start to stop-1 inclusive
150 */
151_GLOBAL(flush_dcache_phys_range)
152 ld r10,PPC64_CACHES@toc(r2)
153 lwz r7,DCACHEL1LINESIZE(r10) /* Get dcache line size */
154 addi r5,r7,-1
155 andc r6,r3,r5 /* round low to line bdy */
156 subf r8,r6,r4 /* compute length */
157 add r8,r8,r5 /* ensure we get enough */
158 lwz r9,DCACHEL1LOGLINESIZE(r10) /* Get log-2 of dcache line size */
159 srw. r8,r8,r9 /* compute line count */
160 beqlr /* nothing to do? */
161 mfmsr r5 /* Disable MMU Data Relocation */
162 ori r0,r5,MSR_DR
163 xori r0,r0,MSR_DR
164 sync
165 mtmsr r0
166 sync
167 isync
168 mtctr r8
1690: dcbst 0,r6
170 add r6,r6,r7
171 bdnz 0b
172 sync
173 isync
174 mtmsr r5 /* Re-enable MMU Data Relocation */
175 sync
176 isync
177 blr
178
179_GLOBAL(flush_inval_dcache_range)
180 ld r10,PPC64_CACHES@toc(r2)
181 lwz r7,DCACHEL1LINESIZE(r10) /* Get dcache line size */
182 addi r5,r7,-1
183 andc r6,r3,r5 /* round low to line bdy */
184 subf r8,r6,r4 /* compute length */
185 add r8,r8,r5 /* ensure we get enough */
186 lwz r9,DCACHEL1LOGLINESIZE(r10)/* Get log-2 of dcache line size */
187 srw. r8,r8,r9 /* compute line count */
188 beqlr /* nothing to do? */
189 sync
190 isync
191 mtctr r8
1920: dcbf 0,r6
193 add r6,r6,r7
194 bdnz 0b
195 sync
196 isync
197 blr
198
199
200/*
201 * Flush a particular page from the data cache to RAM.
202 * Note: this is necessary because the instruction cache does *not*
203 * snoop from the data cache.
204 *
205 * void __flush_dcache_icache(void *page)
206 */
207_GLOBAL(__flush_dcache_icache)
208/*
209 * Flush the data cache to memory
210 *
211 * Different systems have different cache line sizes
212 */
213
214/* Flush the dcache */
215 ld r7,PPC64_CACHES@toc(r2)
216 clrrdi r3,r3,PAGE_SHIFT /* Page align */
217 lwz r4,DCACHEL1LINESPERPAGE(r7) /* Get # dcache lines per page */
218 lwz r5,DCACHEL1LINESIZE(r7) /* Get dcache line size */
219 mr r6,r3
220 mtctr r4
2210: dcbst 0,r6
222 add r6,r6,r5
223 bdnz 0b
224 sync
225
226/* Now invalidate the icache */
227
228 lwz r4,ICACHEL1LINESPERPAGE(r7) /* Get # icache lines per page */
229 lwz r5,ICACHEL1LINESIZE(r7) /* Get icache line size */
230 mtctr r4
2311: icbi 0,r3
232 add r3,r3,r5
233 bdnz 1b
234 isync
235 blr
236
237
238#if defined(CONFIG_PPC_PMAC) || defined(CONFIG_PPC_MAPLE)
239/*
240 * Do an IO access in real mode
241 */
242_GLOBAL(real_readb)
243 mfmsr r7
244 ori r0,r7,MSR_DR
245 xori r0,r0,MSR_DR
246 sync
247 mtmsrd r0
248 sync
249 isync
250 mfspr r6,SPRN_HID4
251 rldicl r5,r6,32,0
252 ori r5,r5,0x100
253 rldicl r5,r5,32,0
254 sync
255 mtspr SPRN_HID4,r5
256 isync
257 slbia
258 isync
259 lbz r3,0(r3)
260 sync
261 mtspr SPRN_HID4,r6
262 isync
263 slbia
264 isync
265 mtmsrd r7
266 sync
267 isync
268 blr
269
270 /*
271 * Do an IO access in real mode
272 */
273_GLOBAL(real_writeb)
274 mfmsr r7
275 ori r0,r7,MSR_DR
276 xori r0,r0,MSR_DR
277 sync
278 mtmsrd r0
279 sync
280 isync
281 mfspr r6,SPRN_HID4
282 rldicl r5,r6,32,0
283 ori r5,r5,0x100
284 rldicl r5,r5,32,0
285 sync
286 mtspr SPRN_HID4,r5
287 isync
288 slbia
289 isync
290 stb r3,0(r4)
291 sync
292 mtspr SPRN_HID4,r6
293 isync
294 slbia
295 isync
296 mtmsrd r7
297 sync
298 isync
299 blr
300#endif /* defined(CONFIG_PPC_PMAC) || defined(CONFIG_PPC_MAPLE) */
301
302#ifdef CONFIG_PPC_PASEMI
303
304/* No support in all binutils for these yet, so use defines */
305#define LBZCIX(RT,RA,RB) .long (0x7c0006aa|(RT<<21)|(RA<<16)|(RB << 11))
306#define STBCIX(RS,RA,RB) .long (0x7c0007aa|(RS<<21)|(RA<<16)|(RB << 11))
307
308
309_GLOBAL(real_205_readb)
310 mfmsr r7
311 ori r0,r7,MSR_DR
312 xori r0,r0,MSR_DR
313 sync
314 mtmsrd r0
315 sync
316 isync
317 LBZCIX(r3,0,r3)
318 isync
319 mtmsrd r7
320 sync
321 isync
322 blr
323
324_GLOBAL(real_205_writeb)
325 mfmsr r7
326 ori r0,r7,MSR_DR
327 xori r0,r0,MSR_DR
328 sync
329 mtmsrd r0
330 sync
331 isync
332 STBCIX(r3,0,r4)
333 isync
334 mtmsrd r7
335 sync
336 isync
337 blr
338
339#endif /* CONFIG_PPC_PASEMI */
340
341
342#if defined(CONFIG_CPU_FREQ_PMAC64) || defined(CONFIG_CPU_FREQ_MAPLE)
343/*
344 * SCOM access functions for 970 (FX only for now)
345 *
346 * unsigned long scom970_read(unsigned int address);
347 * void scom970_write(unsigned int address, unsigned long value);
348 *
349 * The address passed in is the 24 bits register address. This code
350 * is 970 specific and will not check the status bits, so you should
351 * know what you are doing.
352 */
353_GLOBAL(scom970_read)
354 /* interrupts off */
355 mfmsr r4
356 ori r0,r4,MSR_EE
357 xori r0,r0,MSR_EE
358 mtmsrd r0,1
359
360 /* rotate 24 bits SCOM address 8 bits left and mask out it's low 8 bits
361 * (including parity). On current CPUs they must be 0'd,
362 * and finally or in RW bit
363 */
364 rlwinm r3,r3,8,0,15
365 ori r3,r3,0x8000
366
367 /* do the actual scom read */
368 sync
369 mtspr SPRN_SCOMC,r3
370 isync
371 mfspr r3,SPRN_SCOMD
372 isync
373 mfspr r0,SPRN_SCOMC
374 isync
375
376 /* XXX: fixup result on some buggy 970's (ouch ! we lost a bit, bah
377 * that's the best we can do). Not implemented yet as we don't use
378 * the scom on any of the bogus CPUs yet, but may have to be done
379 * ultimately
380 */
381
382 /* restore interrupts */
383 mtmsrd r4,1
384 blr
385
386
387_GLOBAL(scom970_write)
388 /* interrupts off */
389 mfmsr r5
390 ori r0,r5,MSR_EE
391 xori r0,r0,MSR_EE
392 mtmsrd r0,1
393
394 /* rotate 24 bits SCOM address 8 bits left and mask out it's low 8 bits
395 * (including parity). On current CPUs they must be 0'd.
396 */
397
398 rlwinm r3,r3,8,0,15
399
400 sync
401 mtspr SPRN_SCOMD,r4 /* write data */
402 isync
403 mtspr SPRN_SCOMC,r3 /* write command */
404 isync
405 mfspr 3,SPRN_SCOMC
406 isync
407
408 /* restore interrupts */
409 mtmsrd r5,1
410 blr
411#endif /* CONFIG_CPU_FREQ_PMAC64 || CONFIG_CPU_FREQ_MAPLE */
412
413
414/*
415 * Create a kernel thread
416 * kernel_thread(fn, arg, flags)
417 */
418_GLOBAL(kernel_thread)
419 std r29,-24(r1)
420 std r30,-16(r1)
421 stdu r1,-STACK_FRAME_OVERHEAD(r1)
422 mr r29,r3
423 mr r30,r4
424 ori r3,r5,CLONE_VM /* flags */
425 oris r3,r3,(CLONE_UNTRACED>>16)
426 li r4,0 /* new sp (unused) */
427 li r0,__NR_clone
428 sc
429 bns+ 1f /* did system call indicate error? */
430 neg r3,r3 /* if so, make return code negative */
4311: cmpdi 0,r3,0 /* parent or child? */
432 bne 2f /* return if parent */
433 li r0,0
434 stdu r0,-STACK_FRAME_OVERHEAD(r1)
435 ld r2,8(r29)
436 ld r29,0(r29)
437 mtlr r29 /* fn addr in lr */
438 mr r3,r30 /* load arg and call fn */
439 blrl
440 li r0,__NR_exit /* exit after child exits */
441 li r3,0
442 sc
4432: addi r1,r1,STACK_FRAME_OVERHEAD
444 ld r29,-24(r1)
445 ld r30,-16(r1)
446 blr
447
448/*
449 * disable_kernel_fp()
450 * Disable the FPU.
451 */
452_GLOBAL(disable_kernel_fp)
453 mfmsr r3
454 rldicl r0,r3,(63-MSR_FP_LG),1
455 rldicl r3,r0,(MSR_FP_LG+1),0
456 mtmsrd r3 /* disable use of fpu now */
457 isync
458 blr
459
460/* kexec_wait(phys_cpu)
461 *
462 * wait for the flag to change, indicating this kernel is going away but
463 * the slave code for the next one is at addresses 0 to 100.
464 *
465 * This is used by all slaves, even those that did not find a matching
466 * paca in the secondary startup code.
467 *
468 * Physical (hardware) cpu id should be in r3.
469 */
470_GLOBAL(kexec_wait)
471 bl 1f
4721: mflr r5
473 addi r5,r5,kexec_flag-1b
474
47599: HMT_LOW
476#ifdef CONFIG_KEXEC /* use no memory without kexec */
477 lwz r4,0(r5)
478 cmpwi 0,r4,0
479 bnea 0x60
480#endif
481 b 99b
482
483/* this can be in text because we won't change it until we are
484 * running in real anyways
485 */
486kexec_flag:
487 .long 0
488
489
490#ifdef CONFIG_KEXEC
491
492/* kexec_smp_wait(void)
493 *
494 * call with interrupts off
495 * note: this is a terminal routine, it does not save lr
496 *
497 * get phys id from paca
498 * switch to real mode
499 * mark the paca as no longer used
500 * join other cpus in kexec_wait(phys_id)
501 */
502_GLOBAL(kexec_smp_wait)
503 lhz r3,PACAHWCPUID(r13)
504 bl real_mode
505
506 li r4,KEXEC_STATE_REAL_MODE
507 stb r4,PACAKEXECSTATE(r13)
508 SYNC
509
510 b .kexec_wait
511
512/*
513 * switch to real mode (turn mmu off)
514 * we use the early kernel trick that the hardware ignores bits
515 * 0 and 1 (big endian) of the effective address in real mode
516 *
517 * don't overwrite r3 here, it is live for kexec_wait above.
518 */
519real_mode: /* assume normal blr return */
5201: li r9,MSR_RI
521 li r10,MSR_DR|MSR_IR
522 mflr r11 /* return address to SRR0 */
523 mfmsr r12
524 andc r9,r12,r9
525 andc r10,r12,r10
526
527 mtmsrd r9,1
528 mtspr SPRN_SRR1,r10
529 mtspr SPRN_SRR0,r11
530 rfid
531
532
533/*
534 * kexec_sequence(newstack, start, image, control, clear_all())
535 *
536 * does the grungy work with stack switching and real mode switches
537 * also does simple calls to other code
538 */
539
540_GLOBAL(kexec_sequence)
541 mflr r0
542 std r0,16(r1)
543
544 /* switch stacks to newstack -- &kexec_stack.stack */
545 stdu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3)
546 mr r1,r3
547
548 li r0,0
549 std r0,16(r1)
550
551 /* save regs for local vars on new stack.
552 * yes, we won't go back, but ...
553 */
554 std r31,-8(r1)
555 std r30,-16(r1)
556 std r29,-24(r1)
557 std r28,-32(r1)
558 std r27,-40(r1)
559 std r26,-48(r1)
560 std r25,-56(r1)
561
562 stdu r1,-STACK_FRAME_OVERHEAD-64(r1)
563
564 /* save args into preserved regs */
565 mr r31,r3 /* newstack (both) */
566 mr r30,r4 /* start (real) */
567 mr r29,r5 /* image (virt) */
568 mr r28,r6 /* control, unused */
569 mr r27,r7 /* clear_all() fn desc */
570 mr r26,r8 /* spare */
571 lhz r25,PACAHWCPUID(r13) /* get our phys cpu from paca */
572
573 /* disable interrupts, we are overwriting kernel data next */
574 mfmsr r3
575 rlwinm r3,r3,0,17,15
576 mtmsrd r3,1
577
578 /* copy dest pages, flush whole dest image */
579 mr r3,r29
580 bl .kexec_copy_flush /* (image) */
581
582 /* turn off mmu */
583 bl real_mode
584
585 /* copy 0x100 bytes starting at start to 0 */
586 li r3,0
587 mr r4,r30 /* start, aka phys mem offset */
588 li r5,0x100
589 li r6,0
590 bl .copy_and_flush /* (dest, src, copy limit, start offset) */
5911: /* assume normal blr return */
592
593 /* release other cpus to the new kernel secondary start at 0x60 */
594 mflr r5
595 li r6,1
596 stw r6,kexec_flag-1b(5)
597
598 /* clear out hardware hash page table and tlb */
599 ld r5,0(r27) /* deref function descriptor */
600 mtctr r5
601 bctrl /* ppc_md.hpte_clear_all(void); */
602
603/*
604 * kexec image calling is:
605 * the first 0x100 bytes of the entry point are copied to 0
606 *
607 * all slaves branch to slave = 0x60 (absolute)
608 * slave(phys_cpu_id);
609 *
610 * master goes to start = entry point
611 * start(phys_cpu_id, start, 0);
612 *
613 *
614 * a wrapper is needed to call existing kernels, here is an approximate
615 * description of one method:
616 *
617 * v2: (2.6.10)
618 * start will be near the boot_block (maybe 0x100 bytes before it?)
619 * it will have a 0x60, which will b to boot_block, where it will wait
620 * and 0 will store phys into struct boot-block and load r3 from there,
621 * copy kernel 0-0x100 and tell slaves to back down to 0x60 again
622 *
623 * v1: (2.6.9)
624 * boot block will have all cpus scanning device tree to see if they
625 * are the boot cpu ?????
626 * other device tree differences (prop sizes, va vs pa, etc)...
627 */
628 mr r3,r25 # my phys cpu
629 mr r4,r30 # start, aka phys mem offset
630 mtlr 4
631 li r5,0
632 blr /* image->start(physid, image->start, 0); */
633#endif /* CONFIG_KEXEC */