2 * This file contains miscellaneous low-level functions.
3 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
5 * Largely rewritten by Cort Dougan (cort@cs.nmt.edu)
7 * Adapted for iSeries by Mike Corrigan (mikejc@us.ibm.com)
8 * PPC64 updates by Dave Engebretsen (engebret@us.ibm.com)
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.
17 #include <linux/sys.h>
18 #include <asm/unistd.h>
19 #include <asm/errno.h>
20 #include <asm/processor.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>
32 _GLOBAL(call_do_softirq)
35 stdu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3)
46 stdu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r4)
56 .tc ppc64_caches[TC],ppc64_caches
60 * Write any modified data cache blocks out to memory
61 * and invalidate the corresponding instruction cache blocks.
63 * flush_icache_range(unsigned long start, unsigned long stop)
65 * flush all bytes from start through stop-1 inclusive
68 _KPROBE(flush_icache_range)
72 END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
74 * Flush the data cache to memory
76 * Different systems have different cache line sizes
77 * and in some cases i-cache and d-cache line sizes differ from
80 ld r10,PPC64_CACHES@toc(r2)
81 lwz r7,DCACHEL1LINESIZE(r10)/* Get cache line size */
83 andc r6,r3,r5 /* round low to line bdy */
84 subf r8,r6,r4 /* compute length */
85 add r8,r8,r5 /* ensure we get enough */
86 lwz r9,DCACHEL1LOGLINESIZE(r10) /* Get log-2 of cache line size */
87 srw. r8,r8,r9 /* compute line count */
88 beqlr /* nothing to do? */
95 /* Now invalidate the instruction cache */
97 lwz r7,ICACHEL1LINESIZE(r10) /* Get Icache line size */
99 andc r6,r3,r5 /* round low to line bdy */
100 subf r8,r6,r4 /* compute length */
102 lwz r9,ICACHEL1LOGLINESIZE(r10) /* Get log-2 of Icache line size */
103 srw. r8,r8,r9 /* compute line count */
104 beqlr /* nothing to do? */
113 * Like above, but only do the D-cache.
115 * flush_dcache_range(unsigned long start, unsigned long stop)
117 * flush all bytes from start to stop-1 inclusive
119 _GLOBAL(flush_dcache_range)
122 * Flush the data cache to memory
124 * Different systems have different cache line sizes
126 ld r10,PPC64_CACHES@toc(r2)
127 lwz r7,DCACHEL1LINESIZE(r10) /* Get dcache line size */
129 andc r6,r3,r5 /* round low to line bdy */
130 subf r8,r6,r4 /* compute length */
131 add r8,r8,r5 /* ensure we get enough */
132 lwz r9,DCACHEL1LOGLINESIZE(r10) /* Get log-2 of dcache line size */
133 srw. r8,r8,r9 /* compute line count */
134 beqlr /* nothing to do? */
143 * Like above, but works on non-mapped physical addresses.
144 * Use only for non-LPAR setups ! It also assumes real mode
145 * is cacheable. Used for flushing out the DART before using
146 * it as uncacheable memory
148 * flush_dcache_phys_range(unsigned long start, unsigned long stop)
150 * flush all bytes from start to stop-1 inclusive
152 _GLOBAL(flush_dcache_phys_range)
153 ld r10,PPC64_CACHES@toc(r2)
154 lwz r7,DCACHEL1LINESIZE(r10) /* Get dcache line size */
156 andc r6,r3,r5 /* round low to line bdy */
157 subf r8,r6,r4 /* compute length */
158 add r8,r8,r5 /* ensure we get enough */
159 lwz r9,DCACHEL1LOGLINESIZE(r10) /* Get log-2 of dcache line size */
160 srw. r8,r8,r9 /* compute line count */
161 beqlr /* nothing to do? */
162 mfmsr r5 /* Disable MMU Data Relocation */
175 mtmsr r5 /* Re-enable MMU Data Relocation */
180 _GLOBAL(flush_inval_dcache_range)
181 ld r10,PPC64_CACHES@toc(r2)
182 lwz r7,DCACHEL1LINESIZE(r10) /* Get dcache line size */
184 andc r6,r3,r5 /* round low to line bdy */
185 subf r8,r6,r4 /* compute length */
186 add r8,r8,r5 /* ensure we get enough */
187 lwz r9,DCACHEL1LOGLINESIZE(r10)/* Get log-2 of dcache line size */
188 srw. r8,r8,r9 /* compute line count */
189 beqlr /* nothing to do? */
202 * Flush a particular page from the data cache to RAM.
203 * Note: this is necessary because the instruction cache does *not*
204 * snoop from the data cache.
206 * void __flush_dcache_icache(void *page)
208 _GLOBAL(__flush_dcache_icache)
210 * Flush the data cache to memory
212 * Different systems have different cache line sizes
218 END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
220 /* Flush the dcache */
221 ld r7,PPC64_CACHES@toc(r2)
222 clrrdi r3,r3,PAGE_SHIFT /* Page align */
223 lwz r4,DCACHEL1LINESPERPAGE(r7) /* Get # dcache lines per page */
224 lwz r5,DCACHEL1LINESIZE(r7) /* Get dcache line size */
232 /* Now invalidate the icache */
234 lwz r4,ICACHEL1LINESPERPAGE(r7) /* Get # icache lines per page */
235 lwz r5,ICACHEL1LINESIZE(r7) /* Get icache line size */
245 rlwinm r7,r3,8,0xffffffff
247 rlwinm r9,r8,8,0xffffffff
248 rlwimi r7,r3,24,16,23
250 rlwimi r9,r8,24,16,23
256 #ifdef CONFIG_PPC_EARLY_DEBUG_BOOTX
286 #endif /* CONFIG_PPC_EARLY_DEBUG_BOOTX */
288 #if defined(CONFIG_PPC_PMAC) || defined(CONFIG_PPC_MAPLE)
291 * Do an IO access in real mode
322 * Do an IO access in real mode
351 #endif /* defined(CONFIG_PPC_PMAC) || defined(CONFIG_PPC_MAPLE) */
353 #ifdef CONFIG_PPC_PASEMI
355 _GLOBAL(real_205_readb)
370 _GLOBAL(real_205_writeb)
385 #endif /* CONFIG_PPC_PASEMI */
388 #if defined(CONFIG_CPU_FREQ_PMAC64) || defined(CONFIG_CPU_FREQ_MAPLE)
390 * SCOM access functions for 970 (FX only for now)
392 * unsigned long scom970_read(unsigned int address);
393 * void scom970_write(unsigned int address, unsigned long value);
395 * The address passed in is the 24 bits register address. This code
396 * is 970 specific and will not check the status bits, so you should
397 * know what you are doing.
399 _GLOBAL(scom970_read)
406 /* rotate 24 bits SCOM address 8 bits left and mask out it's low 8 bits
407 * (including parity). On current CPUs they must be 0'd,
408 * and finally or in RW bit
413 /* do the actual scom read */
422 /* XXX: fixup result on some buggy 970's (ouch ! we lost a bit, bah
423 * that's the best we can do). Not implemented yet as we don't use
424 * the scom on any of the bogus CPUs yet, but may have to be done
428 /* restore interrupts */
433 _GLOBAL(scom970_write)
440 /* rotate 24 bits SCOM address 8 bits left and mask out it's low 8 bits
441 * (including parity). On current CPUs they must be 0'd.
447 mtspr SPRN_SCOMD,r4 /* write data */
449 mtspr SPRN_SCOMC,r3 /* write command */
454 /* restore interrupts */
457 #endif /* CONFIG_CPU_FREQ_PMAC64 || CONFIG_CPU_FREQ_MAPLE */
459 /* kexec_wait(phys_cpu)
461 * wait for the flag to change, indicating this kernel is going away but
462 * the slave code for the next one is at addresses 0 to 100.
464 * This is used by all slaves, even those that did not find a matching
465 * paca in the secondary startup code.
467 * Physical (hardware) cpu id should be in r3.
472 addi r5,r5,kexec_flag-1b
475 #ifdef CONFIG_KEXEC /* use no memory without kexec */
482 /* this can be in text because we won't change it until we are
483 * running in real anyways
491 /* kexec_smp_wait(void)
493 * call with interrupts off
494 * note: this is a terminal routine, it does not save lr
496 * get phys id from paca
497 * switch to real mode
498 * mark the paca as no longer used
499 * join other cpus in kexec_wait(phys_id)
501 _GLOBAL(kexec_smp_wait)
502 lhz r3,PACAHWCPUID(r13)
505 li r4,KEXEC_STATE_REAL_MODE
506 stb r4,PACAKEXECSTATE(r13)
512 * switch to real mode (turn mmu off)
513 * we use the early kernel trick that the hardware ignores bits
514 * 0 and 1 (big endian) of the effective address in real mode
516 * don't overwrite r3 here, it is live for kexec_wait above.
518 real_mode: /* assume normal blr return */
521 mflr r11 /* return address to SRR0 */
533 * kexec_sequence(newstack, start, image, control, clear_all())
535 * does the grungy work with stack switching and real mode switches
536 * also does simple calls to other code
539 _GLOBAL(kexec_sequence)
543 /* switch stacks to newstack -- &kexec_stack.stack */
544 stdu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3)
550 /* save regs for local vars on new stack.
551 * yes, we won't go back, but ...
561 stdu r1,-STACK_FRAME_OVERHEAD-64(r1)
563 /* save args into preserved regs */
564 mr r31,r3 /* newstack (both) */
565 mr r30,r4 /* start (real) */
566 mr r29,r5 /* image (virt) */
567 mr r28,r6 /* control, unused */
568 mr r27,r7 /* clear_all() fn desc */
569 mr r26,r8 /* spare */
570 lhz r25,PACAHWCPUID(r13) /* get our phys cpu from paca */
572 /* disable interrupts, we are overwriting kernel data next */
577 /* copy dest pages, flush whole dest image */
579 bl .kexec_copy_flush /* (image) */
584 /* copy 0x100 bytes starting at start to 0 */
586 mr r4,r30 /* start, aka phys mem offset */
589 bl .copy_and_flush /* (dest, src, copy limit, start offset) */
590 1: /* assume normal blr return */
592 /* release other cpus to the new kernel secondary start at 0x60 */
595 stw r6,kexec_flag-1b(5)
597 /* clear out hardware hash page table and tlb */
598 ld r5,0(r27) /* deref function descriptor */
600 bctrl /* ppc_md.hpte_clear_all(void); */
603 * kexec image calling is:
604 * the first 0x100 bytes of the entry point are copied to 0
606 * all slaves branch to slave = 0x60 (absolute)
607 * slave(phys_cpu_id);
609 * master goes to start = entry point
610 * start(phys_cpu_id, start, 0);
613 * a wrapper is needed to call existing kernels, here is an approximate
614 * description of one method:
617 * start will be near the boot_block (maybe 0x100 bytes before it?)
618 * it will have a 0x60, which will b to boot_block, where it will wait
619 * and 0 will store phys into struct boot-block and load r3 from there,
620 * copy kernel 0-0x100 and tell slaves to back down to 0x60 again
623 * boot block will have all cpus scanning device tree to see if they
624 * are the boot cpu ?????
625 * other device tree differences (prop sizes, va vs pa, etc)...
627 mr r3,r25 # my phys cpu
628 mr r4,r30 # start, aka phys mem offset
631 blr /* image->start(physid, image->start, 0); */
632 #endif /* CONFIG_KEXEC */