/*
* 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.
*
* kexec bits:
* Copyright (C) 2002-2003 Eric Biederman <ebiederm@xmission.com>
* GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
*
* 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/reg.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>
#include <asm/processor.h>
#include <asm/kexec.h>
#include <asm/bug.h>
.text
#ifdef CONFIG_IRQSTACKS
_GLOBAL(call_do_softirq)
mflr r0
stw r0,4(r1)
stwu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3)
mr r1,r3
bl __do_softirq
lwz r1,0(r1)
lwz r0,4(r1)
mtlr r0
blr
_GLOBAL(call_handle_irq)
mflr r0
stw r0,4(r1)
mtctr r6
stwu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r5)
mr r1,r5
bctrl
lwz r1,0(r1)
lwz r0,4(r1)
mtlr r0
blr
#endif /* CONFIG_IRQSTACKS */
/*
* This returns the high 64 bits of the product of two 64-bit numbers.
*/
_GLOBAL(mulhdu)
cmpwi r6,0
cmpwi cr1,r3,0
mr r10,r4
mulhwu r4,r4,r5
beq 1f
mulhwu r0,r10,r6
mullw r7,r10,r5
addc r7,r0,r7
addze r4,r4
1: beqlr cr1 /* all done if high part of A is 0 */
mr r10,r3
mullw r9,r3,r5
mulhwu r3,r3,r5
beq 2f
mullw r0,r10,r6
mulhwu r8,r10,r6
addc r7,r0,r7
adde r4,r4,r8
addze r3,r3
2: addc r4,r4,r9
addze r3,r3
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)
cmpwi 0,r5,0
add r5,r5,r3
beqlr
mtctr r5
bctr
#if defined(CONFIG_CPU_FREQ_PMAC) && defined(CONFIG_6xx)
/* This gets called by via-pmu.c to switch the PLL selection
* on 750fx CPU. This function should really be moved to some
* other place (as most of the cpufreq code in via-pmu
*/
_GLOBAL(low_choose_750fx_pll)
/* Clear MSR:EE */
mfmsr r7
rlwinm r0,r7,0,17,15
mtmsr r0
/* If switching to PLL1, disable HID0:BTIC */
cmplwi cr0,r3,0
beq 1f
mfspr r5,SPRN_HID0
rlwinm r5,r5,0,27,25
sync
mtspr SPRN_HID0,r5
isync
sync
1:
/* Calc new HID1 value */
mfspr r4,SPRN_HID1 /* Build a HID1:PS bit from parameter */
rlwinm r5,r3,16,15,15 /* Clear out HID1:PS from value read */
rlwinm r4,r4,0,16,14 /* Could have I used rlwimi here ? */
or r4,r4,r5
mtspr SPRN_HID1,r4
/* Store new HID1 image */
rlwinm r6,r1,0,0,(31-THREAD_SHIFT)
lwz r6,TI_CPU(r6)
slwi r6,r6,2
addis r6,r6,nap_save_hid1@ha
stw r4,nap_save_hid1@l(r6)
/* If switching to PLL0, enable HID0:BTIC */
cmplwi cr0,r3,0
bne 1f
mfspr r5,SPRN_HID0
ori r5,r5,HID0_BTIC
sync
mtspr SPRN_HID0,r5
isync
sync
1:
/* Return */
mtmsr r7
blr
_GLOBAL(low_choose_7447a_dfs)
/* Clear MSR:EE */
mfmsr r7
rlwinm r0,r7,0,17,15
mtmsr r0
/* Calc new HID1 value */
mfspr r4,SPRN_HID1
insrwi r4,r3,1,9 /* insert parameter into bit 9 */
sync
mtspr SPRN_HID1,r4
sync
isync
/* Return */
mtmsr r7
blr
#endif /* CONFIG_CPU_FREQ_PMAC && CONFIG_6xx */
/*
* 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 */
#ifdef CONFIG_40x
/*
* Do an IO access in real mode
*/
_GLOBAL(real_readb)
mfmsr r7
ori r0,r7,MSR_DR
xori r0,r0,MSR_DR
sync
mtmsr r0
sync
isync
lbz r3,0(r3)
sync
mtmsr r7
sync
isync
blr
/*
* Do an IO access in real mode
*/
_GLOBAL(real_writeb)
mfmsr r7
ori r0,r7,MSR_DR
xori r0,r0,MSR_DR
sync
mtmsr r0
sync
isync
stb r3,0(r4)
sync
mtmsr r7
sync
isync
blr
#endif /* CONFIG_40x */
/*
* 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)
*/
_KPROBE(__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
/*
* 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
END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
rlwinm r3,r3,0,0,31-PAGE_SHIFT /* Get page base address */
li r4,PAGE_SIZE/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
#ifndef CONFIG_44x
/* We don't flush the icache on 44x. Those have a virtual icache
* and we don't have access to the virtual address here (it's
* not the page vaddr but where it's mapped in user space). The
* flushing of the icache on these is handled elsewhere, when
* a change in the address space occurs, before returning to
* user space
*/
mtctr r4
1: icbi 0,r6
addi r6,r6,L1_CACHE_BYTES
bdnz 1b
sync
isync
#endif /* CONFIG_44x */
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,r3,0,0,31-PAGE_SHIFT /* Get page base address */
li r4,PAGE_SIZE/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,PAGE_SIZE/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,PAGE_SIZE/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
/*
* 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
/*
* 64-bit comparison: __ucmpdi2(u64 a, u64 b)
* Returns 0 if a < b, 1 if a == b, 2 if a > b.
*/
_GLOBAL(__ucmpdi2)
cmplw r3,r5
li r3,1
bne 1f
cmplw r4,r6
beqlr
1: li r3,0
bltlr
li r3,2
blr
_GLOBAL(abs)
srawi r4,r3,31
xor r3,r3,r4
sub r3,r3,r4
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
bns+ 1f /* did system call indicate error? */
neg r3,r3 /* if so, make return code negative */
1: cmpwi 0,r3,0 /* parent or child? */
bne 2f /* 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
2: lwz r30,8(r1)
lwz r31,12(r1)
addi r1,r1,16
blr
/*
* This routine is just here to keep GCC happy - sigh...
*/
_GLOBAL(__main)
blr
#ifdef CONFIG_KEXEC
/*
* Must be relocatable PIC code callable as a C function.
*/
.globl relocate_new_kernel
relocate_new_kernel:
/* r3 = page_list */
/* r4 = reboot_code_buffer */
/* r5 = start_address */
li r0, 0
/*
* Set Machine Status Register to a known status,
* switch the MMU off and jump to 1: in a single step.
*/
mr r8, r0
ori r8, r8, MSR_RI|MSR_ME
mtspr SPRN_SRR1, r8
addi r8, r4, 1f - relocate_new_kernel
mtspr SPRN_SRR0, r8
sync
rfi
1:
/* from this point address translation is turned off */
/* and interrupts are disabled */
/* set a new stack at the bottom of our page... */
/* (not really needed now) */
addi r1, r4, KEXEC_CONTROL_PAGE_SIZE - 8 /* for LR Save+Back Chain */
stw r0, 0(r1)
/* Do the copies */
li r6, 0 /* checksum */
mr r0, r3
b 1f
0: /* top, read another word for the indirection page */
lwzu r0, 4(r3)
1:
/* is it a destination page? (r8) */
rlwinm. r7, r0, 0, 31, 31 /* IND_DESTINATION (1<<0) */
beq 2f
rlwinm r8, r0, 0, 0, 19 /* clear kexec flags, page align */
b 0b
2: /* is it an indirection page? (r3) */
rlwinm. r7, r0, 0, 30, 30 /* IND_INDIRECTION (1<<1) */
beq 2f
rlwinm r3, r0, 0, 0, 19 /* clear kexec flags, page align */
subi r3, r3, 4
b 0b
2: /* are we done? */
rlwinm. r7, r0, 0, 29, 29 /* IND_DONE (1<<2) */
beq 2f
b 3f
2: /* is it a source page? (r9) */
rlwinm. r7, r0, 0, 28, 28 /* IND_SOURCE (1<<3) */
beq 0b
rlwinm r9, r0, 0, 0, 19 /* clear kexec flags, page align */
li r7, PAGE_SIZE / 4
mtctr r7
subi r9, r9, 4
subi r8, r8, 4
9:
lwzu r0, 4(r9) /* do the copy */
xor r6, r6, r0
stwu r0, 4(r8)
dcbst 0, r8
sync
icbi 0, r8
bdnz 9b
addi r9, r9, 4
addi r8, r8, 4
b 0b
3:
/* To be certain of avoiding problems with self-modifying code
* execute a serializing instruction here.
*/
isync
sync
/* jump to the entry point, usually the setup routine */
mtlr r5
blrl
1: b 1b
relocate_new_kernel_end:
.globl relocate_new_kernel_size
relocate_new_kernel_size:
.long relocate_new_kernel_end - relocate_new_kernel
#endif
