linux/arch/powerpc/kernel/misc_32.S
Christophe Leroy 704dfe931d powerpc: Rewrite FSL_BOOKE flush_cache_instruction() in C
Nothing prevents flush_cache_instruction() from being writen in C.

Do it to improve readability and maintainability.

This function is only use by low level callers, it is not
intended to be used by module. Don't export it.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f989eff8296800c427622c0985384148404e4f0b.1597384512.git.christophe.leroy@csgroup.eu
2020-09-02 11:00:21 +10:00

436 lines
8.0 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* 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.
*
*/
#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/export.h>
#include <asm/feature-fixups.h>
.text
/*
* We store the saved ksp_limit in the unused part
* of the STACK_FRAME_OVERHEAD
*/
_GLOBAL(call_do_softirq)
mflr r0
stw r0,4(r1)
lwz r10,THREAD+KSP_LIMIT(r2)
stw r3, THREAD+KSP_LIMIT(r2)
stwu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3)
mr r1,r3
stw r10,8(r1)
bl __do_softirq
lwz r10,8(r1)
lwz r1,0(r1)
lwz r0,4(r1)
stw r10,THREAD+KSP_LIMIT(r2)
mtlr r0
blr
/*
* void call_do_irq(struct pt_regs *regs, void *sp);
*/
_GLOBAL(call_do_irq)
mflr r0
stw r0,4(r1)
lwz r10,THREAD+KSP_LIMIT(r2)
stw r4, THREAD+KSP_LIMIT(r2)
stwu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r4)
mr r1,r4
stw r10,8(r1)
bl __do_irq
lwz r10,8(r1)
lwz r1,0(r1)
lwz r0,4(r1)
stw r10,THREAD+KSP_LIMIT(r2)
mtlr r0
blr
/*
* 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
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_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 */
#ifdef CONFIG_40x
/*
* Do an IO access in real mode
*/
_GLOBAL(real_readb)
mfmsr r7
rlwinm r0,r7,0,~MSR_DR
sync
mtmsr r0
sync
isync
lbz r3,0(r3)
sync
mtmsr r7
sync
isync
blr
_ASM_NOKPROBE_SYMBOL(real_readb)
/*
* Do an IO access in real mode
*/
_GLOBAL(real_writeb)
mfmsr r7
rlwinm r0,r7,0,~MSR_DR
sync
mtmsr r0
sync
isync
stb r3,0(r4)
sync
mtmsr r7
sync
isync
blr
_ASM_NOKPROBE_SYMBOL(real_writeb)
#endif /* CONFIG_40x */
/*
* 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_BUG_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_OVERHEAD
li r3,0
stw r3,0(r1) /* Zero the stack frame pointer */
bl start_secondary
b .
#endif /* CONFIG_SMP */
/*
* This routine is just here to keep GCC happy - sigh...
*/
_GLOBAL(__main)
blr