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 #ifndef CONFIG_PREEMPT_RT_FULL
33 _GLOBAL(call_do_softirq)
36 stdu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3)
48 stdu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r4)
58 .tc ppc64_caches[TC],ppc64_caches
62 * Write any modified data cache blocks out to memory
63 * and invalidate the corresponding instruction cache blocks.
65 * flush_icache_range(unsigned long start, unsigned long stop)
67 * flush all bytes from start through stop-1 inclusive
70 _KPROBE(flush_icache_range)
74 END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
76 * Flush the data cache to memory
78 * Different systems have different cache line sizes
79 * and in some cases i-cache and d-cache line sizes differ from
82 ld r10,PPC64_CACHES@toc(r2)
83 lwz r7,DCACHEL1LINESIZE(r10)/* Get cache line size */
85 andc r6,r3,r5 /* round low to line bdy */
86 subf r8,r6,r4 /* compute length */
87 add r8,r8,r5 /* ensure we get enough */
88 lwz r9,DCACHEL1LOGLINESIZE(r10) /* Get log-2 of cache line size */
89 srw. r8,r8,r9 /* compute line count */
90 beqlr /* nothing to do? */
97 /* Now invalidate the instruction cache */
99 lwz r7,ICACHEL1LINESIZE(r10) /* Get Icache line size */
101 andc r6,r3,r5 /* round low to line bdy */
102 subf r8,r6,r4 /* compute length */
104 lwz r9,ICACHEL1LOGLINESIZE(r10) /* Get log-2 of Icache line size */
105 srw. r8,r8,r9 /* compute line count */
106 beqlr /* nothing to do? */
115 * Like above, but only do the D-cache.
117 * flush_dcache_range(unsigned long start, unsigned long stop)
119 * flush all bytes from start to stop-1 inclusive
121 _GLOBAL(flush_dcache_range)
124 * Flush the data cache to memory
126 * Different systems have different cache line sizes
128 ld r10,PPC64_CACHES@toc(r2)
129 lwz r7,DCACHEL1LINESIZE(r10) /* Get dcache line size */
131 andc r6,r3,r5 /* round low to line bdy */
132 subf r8,r6,r4 /* compute length */
133 add r8,r8,r5 /* ensure we get enough */
134 lwz r9,DCACHEL1LOGLINESIZE(r10) /* Get log-2 of dcache line size */
135 srw. r8,r8,r9 /* compute line count */
136 beqlr /* nothing to do? */
145 * Like above, but works on non-mapped physical addresses.
146 * Use only for non-LPAR setups ! It also assumes real mode
147 * is cacheable. Used for flushing out the DART before using
148 * it as uncacheable memory
150 * flush_dcache_phys_range(unsigned long start, unsigned long stop)
152 * flush all bytes from start to stop-1 inclusive
154 _GLOBAL(flush_dcache_phys_range)
155 ld r10,PPC64_CACHES@toc(r2)
156 lwz r7,DCACHEL1LINESIZE(r10) /* Get dcache line size */
158 andc r6,r3,r5 /* round low to line bdy */
159 subf r8,r6,r4 /* compute length */
160 add r8,r8,r5 /* ensure we get enough */
161 lwz r9,DCACHEL1LOGLINESIZE(r10) /* Get log-2 of dcache line size */
162 srw. r8,r8,r9 /* compute line count */
163 beqlr /* nothing to do? */
164 mfmsr r5 /* Disable MMU Data Relocation */
177 mtmsr r5 /* Re-enable MMU Data Relocation */
182 _GLOBAL(flush_inval_dcache_range)
183 ld r10,PPC64_CACHES@toc(r2)
184 lwz r7,DCACHEL1LINESIZE(r10) /* Get dcache line size */
186 andc r6,r3,r5 /* round low to line bdy */
187 subf r8,r6,r4 /* compute length */
188 add r8,r8,r5 /* ensure we get enough */
189 lwz r9,DCACHEL1LOGLINESIZE(r10)/* Get log-2 of dcache line size */
190 srw. r8,r8,r9 /* compute line count */
191 beqlr /* nothing to do? */
204 * Flush a particular page from the data cache to RAM.
205 * Note: this is necessary because the instruction cache does *not*
206 * snoop from the data cache.
208 * void __flush_dcache_icache(void *page)
210 _GLOBAL(__flush_dcache_icache)
212 * Flush the data cache to memory
214 * Different systems have different cache line sizes
220 END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
222 /* Flush the dcache */
223 ld r7,PPC64_CACHES@toc(r2)
224 clrrdi r3,r3,PAGE_SHIFT /* Page align */
225 lwz r4,DCACHEL1LINESPERPAGE(r7) /* Get # dcache lines per page */
226 lwz r5,DCACHEL1LINESIZE(r7) /* Get dcache line size */
234 /* Now invalidate the icache */
236 lwz r4,ICACHEL1LINESPERPAGE(r7) /* Get # icache lines per page */
237 lwz r5,ICACHEL1LINESIZE(r7) /* Get icache line size */
247 rlwinm r7,r3,8,0xffffffff
249 rlwinm r9,r8,8,0xffffffff
250 rlwimi r7,r3,24,16,23
252 rlwimi r9,r8,24,16,23
258 #ifdef CONFIG_PPC_EARLY_DEBUG_BOOTX
288 #endif /* CONFIG_PPC_EARLY_DEBUG_BOOTX */
290 #if defined(CONFIG_PPC_PMAC) || defined(CONFIG_PPC_MAPLE)
293 * Do an IO access in real mode
324 * Do an IO access in real mode
353 #endif /* defined(CONFIG_PPC_PMAC) || defined(CONFIG_PPC_MAPLE) */
355 #ifdef CONFIG_PPC_PASEMI
357 _GLOBAL(real_205_readb)
372 _GLOBAL(real_205_writeb)
387 #endif /* CONFIG_PPC_PASEMI */
390 #if defined(CONFIG_CPU_FREQ_PMAC64) || defined(CONFIG_CPU_FREQ_MAPLE)
392 * SCOM access functions for 970 (FX only for now)
394 * unsigned long scom970_read(unsigned int address);
395 * void scom970_write(unsigned int address, unsigned long value);
397 * The address passed in is the 24 bits register address. This code
398 * is 970 specific and will not check the status bits, so you should
399 * know what you are doing.
401 _GLOBAL(scom970_read)
408 /* rotate 24 bits SCOM address 8 bits left and mask out it's low 8 bits
409 * (including parity). On current CPUs they must be 0'd,
410 * and finally or in RW bit
415 /* do the actual scom read */
424 /* XXX: fixup result on some buggy 970's (ouch ! we lost a bit, bah
425 * that's the best we can do). Not implemented yet as we don't use
426 * the scom on any of the bogus CPUs yet, but may have to be done
430 /* restore interrupts */
435 _GLOBAL(scom970_write)
442 /* rotate 24 bits SCOM address 8 bits left and mask out it's low 8 bits
443 * (including parity). On current CPUs they must be 0'd.
449 mtspr SPRN_SCOMD,r4 /* write data */
451 mtspr SPRN_SCOMC,r3 /* write command */
456 /* restore interrupts */
459 #endif /* CONFIG_CPU_FREQ_PMAC64 || CONFIG_CPU_FREQ_MAPLE */
461 /* kexec_wait(phys_cpu)
463 * wait for the flag to change, indicating this kernel is going away but
464 * the slave code for the next one is at addresses 0 to 100.
466 * This is used by all slaves, even those that did not find a matching
467 * paca in the secondary startup code.
469 * Physical (hardware) cpu id should be in r3.
474 addi r5,r5,kexec_flag-1b
477 #ifdef CONFIG_KEXEC /* use no memory without kexec */
484 /* this can be in text because we won't change it until we are
485 * running in real anyways
493 /* kexec_smp_wait(void)
495 * call with interrupts off
496 * note: this is a terminal routine, it does not save lr
498 * get phys id from paca
499 * switch to real mode
500 * mark the paca as no longer used
501 * join other cpus in kexec_wait(phys_id)
503 _GLOBAL(kexec_smp_wait)
504 lhz r3,PACAHWCPUID(r13)
507 li r4,KEXEC_STATE_REAL_MODE
508 stb r4,PACAKEXECSTATE(r13)
514 * switch to real mode (turn mmu off)
515 * we use the early kernel trick that the hardware ignores bits
516 * 0 and 1 (big endian) of the effective address in real mode
518 * don't overwrite r3 here, it is live for kexec_wait above.
520 real_mode: /* assume normal blr return */
523 mflr r11 /* return address to SRR0 */
535 * kexec_sequence(newstack, start, image, control, clear_all())
537 * does the grungy work with stack switching and real mode switches
538 * also does simple calls to other code
541 _GLOBAL(kexec_sequence)
545 /* switch stacks to newstack -- &kexec_stack.stack */
546 stdu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3)
552 /* save regs for local vars on new stack.
553 * yes, we won't go back, but ...
563 stdu r1,-STACK_FRAME_OVERHEAD-64(r1)
565 /* save args into preserved regs */
566 mr r31,r3 /* newstack (both) */
567 mr r30,r4 /* start (real) */
568 mr r29,r5 /* image (virt) */
569 mr r28,r6 /* control, unused */
570 mr r27,r7 /* clear_all() fn desc */
571 mr r26,r8 /* spare */
572 lhz r25,PACAHWCPUID(r13) /* get our phys cpu from paca */
574 /* disable interrupts, we are overwriting kernel data next */
579 /* copy dest pages, flush whole dest image */
581 bl kexec_copy_flush /* (image) */
586 /* copy 0x100 bytes starting at start to 0 */
588 mr r4,r30 /* start, aka phys mem offset */
591 bl copy_and_flush /* (dest, src, copy limit, start offset) */
592 1: /* assume normal blr return */
594 /* release other cpus to the new kernel secondary start at 0x60 */
597 stw r6,kexec_flag-1b(5)
599 /* clear out hardware hash page table and tlb */
600 #if !defined(_CALL_ELF) || _CALL_ELF != 2
601 ld r12,0(r27) /* deref function descriptor */
606 bctrl /* ppc_md.hpte_clear_all(void); */
609 * kexec image calling is:
610 * the first 0x100 bytes of the entry point are copied to 0
612 * all slaves branch to slave = 0x60 (absolute)
613 * slave(phys_cpu_id);
615 * master goes to start = entry point
616 * start(phys_cpu_id, start, 0);
619 * a wrapper is needed to call existing kernels, here is an approximate
620 * description of one method:
623 * start will be near the boot_block (maybe 0x100 bytes before it?)
624 * it will have a 0x60, which will b to boot_block, where it will wait
625 * and 0 will store phys into struct boot-block and load r3 from there,
626 * copy kernel 0-0x100 and tell slaves to back down to 0x60 again
629 * boot block will have all cpus scanning device tree to see if they
630 * are the boot cpu ?????
631 * other device tree differences (prop sizes, va vs pa, etc)...
633 mr r3,r25 # my phys cpu
634 mr r4,r30 # start, aka phys mem offset
637 blr /* image->start(physid, image->start, 0); */
638 #endif /* CONFIG_KEXEC */
640 #ifdef CONFIG_MODULES
641 #if defined(_CALL_ELF) && _CALL_ELF == 2
643 #ifdef CONFIG_MODVERSIONS
645 .section "___kcrctab+TOC.","a"
646 .globl __kcrctab_TOC.
652 * Export a fake .TOC. since both modpost and depmod will complain otherwise.
653 * Both modpost and depmod strip the leading . so we do the same here.
655 .section "__ksymtab_strings","a"
659 .section "___ksymtab+TOC.","a"
660 /* This symbol name is important: it's used by modpost to find exported syms */
661 .globl __ksymtab_TOC.
663 .llong 0 /* .value */
664 .llong __kstrtab_TOC.