/*
* This file contains miscellaneous low-level functions.
* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
*
* Largely rewritten by Cort Dougan (cort@cs.nmt.edu)
* and Paul Mackerras.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <linux/sys.h>
#include <asm/unistd.h>
#include <asm/errno.h>
#include <asm/processor.h>
#include <asm/page.h>
#include <asm/cache.h>
#include <asm/cputable.h>
#include <asm/mmu.h>
#include <asm/ppc_asm.h>
#include <asm/thread_info.h>
#include <asm/asm-offsets.h>
#ifdef CONFIG_8xx
#define ISYNC_8xx isync
#else
#define ISYNC_8xx
#endif
.text
.align 5
_GLOBAL(__delay)
cmpwi 0,r3,0
mtctr r3
beqlr
1: bdnz 1b
blr
/*
* Returns (address we're running at) - (address we were linked at)
* for use before the text and data are mapped to KERNELBASE.
*/
_GLOBAL(reloc_offset)
mflr r0
bl 1f
1: mflr r3
lis r4,1b@ha
addi r4,r4,1b@l
subf r3,r4,r3
mtlr r0
blr
/*
* add_reloc_offset(x) returns x + reloc_offset().
*/
_GLOBAL(add_reloc_offset)
mflr r0
bl 1f
1: mflr r5
lis r4,1b@ha
addi r4,r4,1b@l
subf r5,r4,r5
add r3,r3,r5
mtlr r0
blr
/*
* sub_reloc_offset(x) returns x - reloc_offset().
*/
_GLOBAL(sub_reloc_offset)
mflr r0
bl 1f
1: mflr r5
lis r4,1b@ha
addi r4,r4,1b@l
subf r5,r4,r5
subf r3,r5,r3
mtlr r0
blr
/*
* reloc_got2 runs through the .got2 section adding an offset
* to each entry.
*/
_GLOBAL(reloc_got2)
mflr r11
lis r7,__got2_start@ha
addi r7,r7,__got2_start@l
lis r8,__got2_end@ha
addi r8,r8,__got2_end@l
subf r8,r7,r8
srwi. r8,r8,2
beqlr
mtctr r8
bl 1f
1: mflr r0
lis r4,1b@ha
addi r4,r4,1b@l
subf r0,r4,r0
add r7,r0,r7
2: lwz r0,0(r7)
add r0,r0,r3
stw r0,0(r7)
addi r7,r7,4
bdnz 2b
mtlr r11
blr
/*
* call_setup_cpu - call the setup_cpu function for this cpu
* r3 = data offset, r24 = cpu number
*
* Setup function is called with:
* r3 = data offset
* r4 = ptr to CPU spec (relocated)
*/
_GLOBAL(call_setup_cpu)
addis r4,r3,cur_cpu_spec@ha
addi r4,r4,cur_cpu_spec@l
lwz r4,0(r4)
add r4,r4,r3
lwz r5,CPU_SPEC_SETUP(r4)
cmpi 0,r5,0
add r5,r5,r3
beqlr
mtctr r5
bctr
/*
* complement mask on the msr then "or" some values on.
* _nmask_and_or_msr(nmask, value_to_or)
*/
_GLOBAL(_nmask_and_or_msr)
mfmsr r0 /* Get current msr */
andc r0,r0,r3 /* And off the bits set in r3 (first parm) */
or r0,r0,r4 /* Or on the bits in r4 (second parm) */
SYNC /* Some chip revs have problems here... */
mtmsr r0 /* Update machine state */
isync
blr /* Done */
/*
* Flush MMU TLB
*/
_GLOBAL(_tlbia)
#if defined(CONFIG_40x)
sync /* Flush to memory before changing mapping */
tlbia
isync /* Flush shadow TLB */
#elif defined(CONFIG_44x)
li r3,0
sync
/* Load high watermark */
lis r4,tlb_44x_hwater@ha
lwz r5,tlb_44x_hwater@l(r4)
1: tlbwe r3,r3,PPC44x_TLB_PAGEID
addi r3,r3,1
cmpw 0,r3,r5
ble 1b
isync
#elif defined(CONFIG_FSL_BOOKE)
/* Invalidate all entries in TLB0 */
li r3, 0x04
tlbivax 0,3
/* Invalidate all entries in TLB1 */
li r3, 0x0c
tlbivax 0,3
/* Invalidate all entries in TLB2 */
li r3, 0x14
tlbivax 0,3
/* Invalidate all entries in TLB3 */
li r3, 0x1c
tlbivax 0,3
msync
#ifdef CONFIG_SMP
tlbsync
#endif /* CONFIG_SMP */
#else /* !(CONFIG_40x || CONFIG_44x || CONFIG_FSL_BOOKE) */
#if defined(CONFIG_SMP)
rlwinm r8,r1,0,0,18
lwz r8,TI_CPU(r8)
oris r8,r8,10
mfmsr r10
SYNC
rlwinm r0,r10,0,17,15 /* clear bit 16 (MSR_EE) */
rlwinm r0,r0,0,28,26 /* clear DR */
mtmsr r0
SYNC_601
isync
lis r9,mmu_hash_lock@h
ori r9,r9,mmu_hash_lock@l
tophys(r9,r9)
10: lwarx r7,0,r9
cmpwi 0,r7,0
bne- 10b
stwcx. r8,0,r9
bne- 10b
sync
tlbia
sync
TLBSYNC
li r0,0
stw r0,0(r9) /* clear mmu_hash_lock */
mtmsr r10
SYNC_601
isync
#else /* CONFIG_SMP */
sync
tlbia
sync
#endif /* CONFIG_SMP */
#endif /* ! defined(CONFIG_40x) */
blr
/*
* Flush MMU TLB for a particular address
*/
_GLOBAL(_tlbie)
#if defined(CONFIG_40x)
tlbsx. r3, 0, r3
bne 10f
sync
/* There are only 64 TLB entries, so r3 < 64, which means bit 25 is clear.
* Since 25 is the V bit in the TLB_TAG, loading this value will invalidate
* the TLB entry. */
tlbwe r3, r3, TLB_TAG
isync
10:
#elif defined(CONFIG_44x)
mfspr r4,SPRN_MMUCR
mfspr r5,SPRN_PID /* Get PID */
rlwimi r4,r5,0,24,31 /* Set TID */
/* We have to run the search with interrupts disabled, even critical
* and debug interrupts (in fact the only critical exceptions we have
* are debug and machine check). Otherwise an interrupt which causes
* a TLB miss can clobber the MMUCR between the mtspr and the tlbsx. */
mfmsr r5
lis r6,(MSR_EE|MSR_CE|MSR_ME|MSR_DE)@ha
addi r6,r6,(MSR_EE|MSR_CE|MSR_ME|MSR_DE)@l
andc r6,r5,r6
mtmsr r6
mtspr SPRN_MMUCR,r4
tlbsx. r3, 0, r3
mtmsr r5
bne 10f
sync
/* There are only 64 TLB entries, so r3 < 64,
* which means bit 22, is clear. Since 22 is
* the V bit in the TLB_PAGEID, loading this
* value will invalidate the TLB entry.
*/
tlbwe r3, r3, PPC44x_TLB_PAGEID
isync
10:
#elif defined(CONFIG_FSL_BOOKE)
rlwinm r4, r3, 0, 0, 19
ori r5, r4, 0x08 /* TLBSEL = 1 */
ori r6, r4, 0x10 /* TLBSEL = 2 */
ori r7, r4, 0x18 /* TLBSEL = 3 */
tlbivax 0, r4
tlbivax 0, r5
tlbivax 0, r6
tlbivax 0, r7
msync
#if defined(CONFIG_SMP)
tlbsync
#endif /* CONFIG_SMP */
#else /* !(CONFIG_40x || CONFIG_44x || CONFIG_FSL_BOOKE) */
#if defined(CONFIG_SMP)
rlwinm r8,r1,0,0,18
lwz r8,TI_CPU(r8)
oris r8,r8,11
mfmsr r10
SYNC
rlwinm r0,r10,0,17,15 /* clear bit 16 (MSR_EE) */
rlwinm r0,r0,0,28,26 /* clear DR */
mtmsr r0
SYNC_601
isync
lis r9,mmu_hash_lock@h
ori r9,r9,mmu_hash_lock@l
tophys(r9,r9)
10: lwarx r7,0,r9
cmpwi 0,r7,0
bne- 10b
stwcx. r8,0,r9
bne- 10b
eieio
tlbie r3
sync
TLBSYNC
li r0,0
stw r0,0(r9) /* clear mmu_hash_lock */
mtmsr r10
SYNC_601
isync
#else /* CONFIG_SMP */
tlbie r3
sync
#endif /* CONFIG_SMP */
#endif /* ! CONFIG_40x */
blr
/*
* Flush instruction cache.
* This is a no-op on the 601.
*/
_GLOBAL(flush_instruction_cache)
#if defined(CONFIG_8xx)
isync
lis r5, IDC_INVALL@h
mtspr SPRN_IC_CST, r5
#elif defined(CONFIG_4xx)
#ifdef CONFIG_403GCX
li r3, 512
mtctr r3
lis r4, KERNELBASE@h
1: iccci 0, r4
addi r4, r4, 16
bdnz 1b
#else
lis r3, KERNELBASE@h
iccci 0,r3
#endif
#elif CONFIG_FSL_BOOKE
BEGIN_FTR_SECTION
mfspr r3,SPRN_L1CSR0
ori r3,r3,L1CSR0_CFI|L1CSR0_CLFC
/* msync; isync recommended here */
mtspr SPRN_L1CSR0,r3
isync
blr
END_FTR_SECTION_IFSET(CPU_FTR_UNIFIED_ID_CACHE)
mfspr r3,SPRN_L1CSR1
ori r3,r3,L1CSR1_ICFI|L1CSR1_ICLFR
mtspr SPRN_L1CSR1,r3
#else
mfspr r3,SPRN_PVR
rlwinm r3,r3,16,16,31
cmpwi 0,r3,1
beqlr /* for 601, do nothing */
/* 603/604 processor - use invalidate-all bit in HID0 */
mfspr r3,SPRN_HID0
ori r3,r3,HID0_ICFI
mtspr SPRN_HID0,r3
#endif /* CONFIG_8xx/4xx */
isync
blr
/*
* Write any modified data cache blocks out to memory
* and invalidate the corresponding instruction cache blocks.
* This is a no-op on the 601.
*
* __flush_icache_range(unsigned long start, unsigned long stop)
*/
_GLOBAL(__flush_icache_range)
BEGIN_FTR_SECTION
blr /* for 601, do nothing */
END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
li r5,L1_CACHE_BYTES-1
andc r3,r3,r5
subf r4,r3,r4
add r4,r4,r5
srwi. r4,r4,L1_CACHE_SHIFT
beqlr
mtctr r4
mr r6,r3
1: dcbst 0,r3
addi r3,r3,L1_CACHE_BYTES
bdnz 1b
sync /* wait for dcbst's to get to ram */
mtctr r4
2: icbi 0,r6
addi r6,r6,L1_CACHE_BYTES
bdnz 2b
sync /* additional sync needed on g4 */
isync
blr
/*
* Write any modified data cache blocks out to memory.
* Does not invalidate the corresponding cache lines (especially for
* any corresponding instruction cache).
*
* clean_dcache_range(unsigned long start, unsigned long stop)
*/
_GLOBAL(clean_dcache_range)
li r5,L1_CACHE_BYTES-1
andc r3,r3,r5
subf r4,r3,r4
add r4,r4,r5
srwi. r4,r4,L1_CACHE_SHIFT
beqlr
mtctr r4
1: dcbst 0,r3
addi r3,r3,L1_CACHE_BYTES
bdnz 1b
sync /* wait for dcbst's to get to ram */
blr
/*
* Write any modified data cache blocks out to memory and invalidate them.
* Does not invalidate the corresponding instruction cache blocks.
*
* flush_dcache_range(unsigned long start, unsigned long stop)
*/
_GLOBAL(flush_dcache_range)
li r5,L1_CACHE_BYTES-1
andc r3,r3,r5
subf r4,r3,r4
add r4,r4,r5
srwi. r4,r4,L1_CACHE_SHIFT
beqlr
mtctr r4
1: dcbf 0,r3
addi r3,r3,L1_CACHE_BYTES
bdnz 1b
sync /* wait for dcbst's to get to ram */
blr
/*
* Like above, but invalidate the D-cache. This is used by the 8xx
* to invalidate the cache so the PPC core doesn't get stale data
* from the CPM (no cache snooping here :-).
*
* invalidate_dcache_range(unsigned long start, unsigned long stop)
*/
_GLOBAL(invalidate_dcache_range)
li r5,L1_CACHE_BYTES-1
andc r3,r3,r5
subf r4,r3,r4
add r4,r4,r5
srwi. r4,r4,L1_CACHE_SHIFT
beqlr
mtctr r4
1: dcbi 0,r3
addi r3,r3,L1_CACHE_BYTES
bdnz 1b
sync /* wait for dcbi's to get to ram */
blr
#ifdef CONFIG_NOT_COHERENT_CACHE
/*
* 40x cores have 8K or 16K dcache and 32 byte line size.
* 44x has a 32K dcache and 32 byte line size.
* 8xx has 1, 2, 4, 8K variants.
* For now, cover the worst case of the 44x.
* Must be called with external interrupts disabled.
*/
#define CACHE_NWAYS 64
#define CACHE_NLINES 16
_GLOBAL(flush_dcache_all)
li r4, (2 * CACHE_NWAYS * CACHE_NLINES)
mtctr r4
lis r5, KERNELBASE@h
1: lwz r3, 0(r5) /* Load one word from every line */
addi r5, r5, L1_CACHE_BYTES
bdnz 1b
blr
#endif /* CONFIG_NOT_COHERENT_CACHE */
/*
* Flush a particular page from the data cache to RAM.
* Note: this is necessary because the instruction cache does *not*
* snoop from the data cache.
* This is a no-op on the 601 which has a unified cache.
*
* void __flush_dcache_icache(void *page)
*/
_GLOBAL(__flush_dcache_icache)
BEGIN_FTR_SECTION
blr /* for 601, do nothing */
END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
rlwinm r3,r3,0,0,19 /* Get page base address */
li r4,4096/L1_CACHE_BYTES /* Number of lines in a page */
mtctr r4
mr r6,r3
0: dcbst 0,r3 /* Write line to ram */
addi r3,r3,L1_CACHE_BYTES
bdnz 0b
sync
mtctr r4
1: icbi 0,r6
addi r6,r6,L1_CACHE_BYTES
bdnz 1b
sync
isync
blr
/*
* Flush a particular page from the data cache to RAM, identified
* by its physical address. We turn off the MMU so we can just use
* the physical address (this may be a highmem page without a kernel
* mapping).
*
* void __flush_dcache_icache_phys(unsigned long physaddr)
*/
_GLOBAL(__flush_dcache_icache_phys)
BEGIN_FTR_SECTION
blr /* for 601, do nothing */
END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
mfmsr r10
rlwinm r0,r10,0,28,26 /* clear DR */
mtmsr r0
isync
rlwinm r3,r3,0,0,19 /* Get page base address */
li r4,4096/L1_CACHE_BYTES /* Number of lines in a page */
mtctr r4
mr r6,r3
0: dcbst 0,r3 /* Write line to ram */
addi r3,r3,L1_CACHE_BYTES
bdnz 0b
sync
mtctr r4
1: icbi 0,r6
addi r6,r6,L1_CACHE_BYTES
bdnz 1b
sync
mtmsr r10 /* restore DR */
isync
blr
/*
* Clear pages using the dcbz instruction, which doesn't cause any
* memory traffic (except to write out any cache lines which get
* displaced). This only works on cacheable memory.
*
* void clear_pages(void *page, int order) ;
*/
_GLOBAL(clear_pages)
li r0,4096/L1_CACHE_BYTES
slw r0,r0,r4
mtctr r0
#ifdef CONFIG_8xx
li r4, 0
1: stw r4, 0(r3)
stw r4, 4(r3)
stw r4, 8(r3)
stw r4, 12(r3)
#else
1: dcbz 0,r3
#endif
addi r3,r3,L1_CACHE_BYTES
bdnz 1b
blr
/*
* Copy a whole page. We use the dcbz instruction on the destination
* to reduce memory traffic (it eliminates the unnecessary reads of
* the destination into cache). This requires that the destination
* is cacheable.
*/
#define COPY_16_BYTES \
lwz r6,4(r4); \
lwz r7,8(r4); \
lwz r8,12(r4); \
lwzu r9,16(r4); \
stw r6,4(r3); \
stw r7,8(r3); \
stw r8,12(r3); \
stwu r9,16(r3)
_GLOBAL(copy_page)
addi r3,r3,-4
addi r4,r4,-4
#ifdef CONFIG_8xx
/* don't use prefetch on 8xx */
li r0,4096/L1_CACHE_BYTES
mtctr r0
1: COPY_16_BYTES
bdnz 1b
blr
#else /* not 8xx, we can prefetch */
li r5,4
#if MAX_COPY_PREFETCH > 1
li r0,MAX_COPY_PREFETCH
li r11,4
mtctr r0
11: dcbt r11,r4
addi r11,r11,L1_CACHE_BYTES
bdnz 11b
#else /* MAX_COPY_PREFETCH == 1 */
dcbt r5,r4
li r11,L1_CACHE_BYTES+4
#endif /* MAX_COPY_PREFETCH */
li r0,4096/L1_CACHE_BYTES - MAX_COPY_PREFETCH
crclr 4*cr0+eq
2:
mtctr r0
1:
dcbt r11,r4
dcbz r5,r3
COPY_16_BYTES
#if L1_CACHE_BYTES >= 32
COPY_16_BYTES
#if L1_CACHE_BYTES >= 64
COPY_16_BYTES
COPY_16_BYTES
#if L1_CACHE_BYTES >= 128
COPY_16_BYTES
COPY_16_BYTES
COPY_16_BYTES
COPY_16_BYTES
#endif
#endif
#endif
bdnz 1b
beqlr
crnot 4*cr0+eq,4*cr0+eq
li r0,MAX_COPY_PREFETCH
li r11,4
b 2b
#endif /* CONFIG_8xx */
/*
* void atomic_clear_mask(atomic_t mask, atomic_t *addr)
* void atomic_set_mask(atomic_t mask, atomic_t *addr);
*/
_GLOBAL(atomic_clear_mask)
10: lwarx r5,0,r4
andc r5,r5,r3
PPC405_ERR77(0,r4)
stwcx. r5,0,r4
bne- 10b
blr
_GLOBAL(atomic_set_mask)
10: lwarx r5,0,r4
or r5,r5,r3
PPC405_ERR77(0,r4)
stwcx. r5,0,r4
bne- 10b
blr
/*
* I/O string operations
*
* insb(port, buf, len)
* outsb(port, buf, len)
* insw(port, buf, len)
* outsw(port, buf, len)
* insl(port, buf, len)
* outsl(port, buf, len)
* insw_ns(port, buf, len)
* outsw_ns(port, buf, len)
* insl_ns(port, buf, len)
* outsl_ns(port, buf, len)
*
* The *_ns versions don't do byte-swapping.
*/
_GLOBAL(_insb)
cmpwi 0,r5,0
mtctr r5
subi r4,r4,1
blelr-
00: lbz r5,0(r3)
01: eieio
02: stbu r5,1(r4)
ISYNC_8xx
.section .fixup,"ax"
03: blr
.text
.section __ex_table, "a"
.align 2
.long 00b, 03b
.long 01b, 03b
.long 02b, 03b
.text
bdnz 00b
blr
_GLOBAL(_outsb)
cmpwi 0,r5,0
mtctr r5
subi r4,r4,1
blelr-
00: lbzu r5,1(r4)
01: stb r5,0(r3)
02: eieio
ISYNC_8xx
.section .fixup,"ax"
03: blr
.text
.section __ex_table, "a"
.align 2
.long 00b, 03b
.long 01b, 03b
.long 02b, 03b
.text
bdnz 00b
blr
_GLOBAL(_insw_ns)
cmpwi 0,r5,0
mtctr r5
subi r4,r4,2
blelr-
00: lhz r5,0(r3)
01: eieio
02: sthu r5,2(r4)
ISYNC_8xx
.section .fixup,"ax"
03: blr
.text
.section __ex_table, "a"
.align 2
.long 00b, 03b
.long 01b, 03b
.long 02b, 03b
.text
bdnz 00b
blr
_GLOBAL(_outsw_ns)
cmpwi 0,r5,0
mtctr r5
subi r4,r4,2
blelr-
00: lhzu r5,2(r4)
01: sth r5,0(r3)
02: eieio
ISYNC_8xx
.section .fixup,"ax"
03: blr
.text
.section __ex_table, "a"
.align 2
.long 00b, 03b
.long 01b, 03b
.long 02b, 03b
.text
bdnz 00b
blr
_GLOBAL(_insl_ns)
cmpwi 0,r5,0
mtctr r5
subi r4,r4,4
blelr-
00: lwz r5,0(r3)
01: eieio
02: stwu r5,4(r4)
ISYNC_8xx
.section .fixup,"ax"
03: blr
.text
.section __ex_table, "a"
.align 2
.long 00b, 03b
.long 01b, 03b
.long 02b, 03b
.text
bdnz 00b
blr
_GLOBAL(_outsl_ns)
cmpwi 0,r5,0
mtctr r5
subi r4,r4,4
blelr-
00: lwzu r5,4(r4)
01: stw r5,0(r3)
02: eieio
ISYNC_8xx
.section .fixup,"ax"
03: blr
.text
.section __ex_table, "a"
.align 2
.long 00b, 03b
.long 01b, 03b
.long 02b, 03b
.text
bdnz 00b
blr
/*
* Extended precision shifts.
*
* Updated to be valid for shift counts from 0 to 63 inclusive.
* -- Gabriel
*
* R3/R4 has 64 bit value
* R5 has shift count
* result in R3/R4
*
* ashrdi3: arithmetic right shift (sign propagation)
* lshrdi3: logical right shift
* ashldi3: left shift
*/
_GLOBAL(__ashrdi3)
subfic r6,r5,32
srw r4,r4,r5 # LSW = count > 31 ? 0 : LSW >> count
addi r7,r5,32 # could be xori, or addi with -32
slw r6,r3,r6 # t1 = count > 31 ? 0 : MSW << (32-count)
rlwinm r8,r7,0,32 # t3 = (count < 32) ? 32 : 0
sraw r7,r3,r7 # t2 = MSW >> (count-32)
or r4,r4,r6 # LSW |= t1
slw r7,r7,r8 # t2 = (count < 32) ? 0 : t2
sraw r3,r3,r5 # MSW = MSW >> count
or r4,r4,r7 # LSW |= t2
blr
_GLOBAL(__ashldi3)
subfic r6,r5,32
slw r3,r3,r5 # MSW = count > 31 ? 0 : MSW << count
addi r7,r5,32 # could be xori, or addi with -32
srw r6,r4,r6 # t1 = count > 31 ? 0 : LSW >> (32-count)
slw r7,r4,r7 # t2 = count < 32 ? 0 : LSW << (count-32)
or r3,r3,r6 # MSW |= t1
slw r4,r4,r5 # LSW = LSW << count
or r3,r3,r7 # MSW |= t2
blr
_GLOBAL(__lshrdi3)
subfic r6,r5,32
srw r4,r4,r5 # LSW = count > 31 ? 0 : LSW >> count
addi r7,r5,32 # could be xori, or addi with -32
slw r6,r3,r6 # t1 = count > 31 ? 0 : MSW << (32-count)
srw r7,r3,r7 # t2 = count < 32 ? 0 : MSW >> (count-32)
or r4,r4,r6 # LSW |= t1
srw r3,r3,r5 # MSW = MSW >> count
or r4,r4,r7 # LSW |= t2
blr
_GLOBAL(abs)
srawi r4,r3,31
xor r3,r3,r4
sub r3,r3,r4
blr
_GLOBAL(_get_SP)
mr r3,r1 /* Close enough */
blr
/*
* Create a kernel thread
* kernel_thread(fn, arg, flags)
*/
_GLOBAL(kernel_thread)
stwu r1,-16(r1)
stw r30,8(r1)
stw r31,12(r1)
mr r30,r3 /* function */
mr r31,r4 /* argument */
ori r3,r5,CLONE_VM /* flags */
oris r3,r3,CLONE_UNTRACED>>16
li r4,0 /* new sp (unused) */
li r0,__NR_clone
sc
cmpwi 0,r3,0 /* parent or child? */
bne 1f /* return if parent */
li r0,0 /* make top-level stack frame */
stwu r0,-16(r1)
mtlr r30 /* fn addr in lr */
mr r3,r31 /* load arg and call fn */
PPC440EP_ERR42
blrl
li r0,__NR_exit /* exit if function returns */
li r3,0
sc
1: lwz r30,8(r1)
lwz r31,12(r1)
addi r1,r1,16
blr
_GLOBAL(kernel_execve)
li r0,__NR_execve
sc
bnslr
neg r3,r3
blr
/*
* This routine is just here to keep GCC happy - sigh...
*/
_GLOBAL(__main)
blr
