/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* This file contains miscellaneous low-level functions.
* Copyright (C) 1995-1996 Gary Thomas ([email protected])
*
* Largely rewritten by Cort Dougan ([email protected])
* and Paul Mackerras.
*
*/
#include <linux/export.h>
#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/bug.h>
#include <asm/ptrace.h>
#include <asm/feature-fixups.h>
.text
/*
* 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 */
mullw r9,r3,r5
mulhwu r10,r3,r5
beq 2f
mullw r0,r3,r6
mulhwu r8,r3,r6
addc r7,r0,r7
adde r4,r4,r8
addze r10,r10
2: addc r4,r4,r9
addze r3,r10
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
bcl 20,31,$+4
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_PPC_BOOK3S_32)
/* 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
#ifdef CONFIG_SMP
/* Store new HID1 image */
lwz r6,TASK_CPU(r2)
slwi r6,r6,2
#else
li r6, 0
#endif
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_PPC_BOOK3S_32 */
/*
* 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)
rlwinm r5, r3, 0, L1_CACHE_BYTES - 1
addi r3,r3,-4
0: twnei r5, 0 /* WARN if r3 is not cache aligned */
EMIT_WARN_ENTRY 0b,__FILE__,__LINE__, BUGFLAG_WARNING
addi r4,r4,-4
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
EXPORT_SYMBOL(copy_page)
/*
* 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
EXPORT_SYMBOL(__ashrdi3)
_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
EXPORT_SYMBOL(__ashldi3)
_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
EXPORT_SYMBOL(__lshrdi3)
/*
* 64-bit comparison: __cmpdi2(s64 a, s64 b)
* Returns 0 if a < b, 1 if a == b, 2 if a > b.
*/
_GLOBAL(__cmpdi2)
cmpw r3,r5
li r3,1
bne 1f
cmplw r4,r6
beqlr
1: li r3,0
bltlr
li r3,2
blr
EXPORT_SYMBOL(__cmpdi2)
/*
* 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
EXPORT_SYMBOL(__ucmpdi2)
_GLOBAL(__bswapdi2)
rotlwi r9,r4,8
rotlwi r10,r3,8
rlwimi r9,r4,24,0,7
rlwimi r10,r3,24,0,7
rlwimi r9,r4,24,16,23
rlwimi r10,r3,24,16,23
mr r3,r9
mr r4,r10
blr
EXPORT_SYMBOL(__bswapdi2)
#ifdef CONFIG_SMP
_GLOBAL(start_secondary_resume)
/* Reset stack */
rlwinm r1, r1, 0, 0, 31 - THREAD_SHIFT
addi r1,r1,THREAD_SIZE-STACK_FRAME_MIN_SIZE
li r3,0
stw r3,0(r1) /* Zero the stack frame pointer */
bl start_secondary
b .
#endif /* CONFIG_SMP */
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