/*
* linux/arch/arm/mm/cache-v7.S
*
* Copyright (C) 2001 Deep Blue Solutions Ltd.
* Copyright (C) 2005 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This is the "shell" of the ARMv7 processor support.
*/
#include <linux/linkage.h>
#include <linux/init.h>
#include <asm/assembler.h>
#include "proc-macros.S"
/*
* v7_flush_dcache_all()
*
* Flush the whole D-cache.
*
* Corrupted registers: r0-r5, r7, r9-r11
*
* - mm - mm_struct describing address space
*/
ENTRY(v7_flush_dcache_all)
dmb @ ensure ordering with previous memory accesses
mrc p15, 1, r0, c0, c0, 1 @ read clidr
ands r3, r0, #0x7000000 @ extract loc from clidr
mov r3, r3, lsr #23 @ left align loc bit field
beq finished @ if loc is 0, then no need to clean
mov r10, #0 @ start clean at cache level 0
loop1:
add r2, r10, r10, lsr #1 @ work out 3x current cache level
mov r1, r0, lsr r2 @ extract cache type bits from clidr
and r1, r1, #7 @ mask of the bits for current cache only
cmp r1, #2 @ see what cache we have at this level
blt skip @ skip if no cache, or just i-cache
mcr p15, 2, r10, c0, c0, 0 @ select current cache level in cssr
isb @ isb to sych the new cssr&csidr
mrc p15, 1, r1, c0, c0, 0 @ read the new csidr
and r2, r1, #7 @ extract the length of the cache lines
add r2, r2, #4 @ add 4 (line length offset)
ldr r4, =0x3ff
ands r4, r4, r1, lsr #3 @ find maximum number on the way size
clz r5, r4 @ find bit position of way size increment
ldr r7, =0x7fff
ands r7, r7, r1, lsr #13 @ extract max number of the index size
loop2:
mov r9, r4 @ create working copy of max way size
loop3:
orr r11, r10, r9, lsl r5 @ factor way and cache number into r11
orr r11, r11, r7, lsl r2 @ factor index number into r11
mcr p15, 0, r11, c7, c14, 2 @ clean & invalidate by set/way
subs r9, r9, #1 @ decrement the way
bge loop3
subs r7, r7, #1 @ decrement the index
bge loop2
skip:
add r10, r10, #2 @ increment cache number
cmp r3, r10
bgt loop1
finished:
mov r10, #0 @ swith back to cache level 0
mcr p15, 2, r10, c0, c0, 0 @ select current cache level in cssr
dsb
isb
mov pc, lr
ENDPROC(v7_flush_dcache_all)
/*
* v7_flush_cache_all()
*
* Flush the entire cache system.
* The data cache flush is now achieved using atomic clean / invalidates
* working outwards from L1 cache. This is done using Set/Way based cache
* maintainance instructions.
* The instruction cache can still be invalidated back to the point of
* unification in a single instruction.
*
*/
ENTRY(v7_flush_kern_cache_all)
stmfd sp!, {r4-r5, r7, r9-r11, lr}
bl v7_flush_dcache_all
mov r0, #0
mcr p15, 0, r0, c7, c5, 0 @ I+BTB cache invalidate
ldmfd sp!, {r4-r5, r7, r9-r11, lr}
mov pc, lr
ENDPROC(v7_flush_kern_cache_all)
/*
* v7_flush_cache_all()
*
* Flush all TLB entries in a particular address space
*
* - mm - mm_struct describing address space
*/
ENTRY(v7_flush_user_cache_all)
/*FALLTHROUGH*/
/*
* v7_flush_cache_range(start, end, flags)
*
* Flush a range of TLB entries in the specified address space.
*
* - start - start address (may not be aligned)
* - end - end address (exclusive, may not be aligned)
* - flags - vm_area_struct flags describing address space
*
* It is assumed that:
* - we have a VIPT cache.
*/
ENTRY(v7_flush_user_cache_range)
mov pc, lr
ENDPROC(v7_flush_user_cache_all)
ENDPROC(v7_flush_user_cache_range)
/*
* v7_coherent_kern_range(start,end)
*
* Ensure that the I and D caches are coherent within specified
* region. This is typically used when code has been written to
* a memory region, and will be executed.
*
* - start - virtual start address of region
* - end - virtual end address of region
*
* It is assumed that:
* - the Icache does not read data from the write buffer
*/
ENTRY(v7_coherent_kern_range)
/* FALLTHROUGH */
/*
* v7_coherent_user_range(start,end)
*
* Ensure that the I and D caches are coherent within specified
* region. This is typically used when code has been written to
* a memory region, and will be executed.
*
* - start - virtual start address of region
* - end - virtual end address of region
*
* It is assumed that:
* - the Icache does not read data from the write buffer
*/
ENTRY(v7_coherent_user_range)
dcache_line_size r2, r3
sub r3, r2, #1
bic r0, r0, r3
1: mcr p15, 0, r0, c7, c11, 1 @ clean D line to the point of unification
dsb
mcr p15, 0, r0, c7, c5, 1 @ invalidate I line
add r0, r0, r2
cmp r0, r1
blo 1b
mov r0, #0
mcr p15, 0, r0, c7, c5, 6 @ invalidate BTB
dsb
isb
mov pc, lr
ENDPROC(v7_coherent_kern_range)
ENDPROC(v7_coherent_user_range)
/*
* v7_flush_kern_dcache_page(kaddr)
*
* Ensure that the data held in the page kaddr is written back
* to the page in question.
*
* - kaddr - kernel address (guaranteed to be page aligned)
*/
ENTRY(v7_flush_kern_dcache_page)
dcache_line_size r2, r3
add r1, r0, #PAGE_SZ
1:
mcr p15, 0, r0, c7, c14, 1 @ clean & invalidate D line / unified line
add r0, r0, r2
cmp r0, r1
blo 1b
dsb
mov pc, lr
ENDPROC(v7_flush_kern_dcache_page)
/*
* v7_dma_inv_range(start,end)
*
* Invalidate the data cache within the specified region; we will
* be performing a DMA operation in this region and we want to
* purge old data in the cache.
*
* - start - virtual start address of region
* - end - virtual end address of region
*/
ENTRY(v7_dma_inv_range)
dcache_line_size r2, r3
sub r3, r2, #1
tst r0, r3
bic r0, r0, r3
mcrne p15, 0, r0, c7, c14, 1 @ clean & invalidate D / U line
tst r1, r3
bic r1, r1, r3
mcrne p15, 0, r1, c7, c14, 1 @ clean & invalidate D / U line
1:
mcr p15, 0, r0, c7, c6, 1 @ invalidate D / U line
add r0, r0, r2
cmp r0, r1
blo 1b
dsb
mov pc, lr
ENDPROC(v7_dma_inv_range)
/*
* v7_dma_clean_range(start,end)
* - start - virtual start address of region
* - end - virtual end address of region
*/
ENTRY(v7_dma_clean_range)
dcache_line_size r2, r3
sub r3, r2, #1
bic r0, r0, r3
1:
mcr p15, 0, r0, c7, c10, 1 @ clean D / U line
add r0, r0, r2
cmp r0, r1
blo 1b
dsb
mov pc, lr
ENDPROC(v7_dma_clean_range)
/*
* v7_dma_flush_range(start,end)
* - start - virtual start address of region
* - end - virtual end address of region
*/
ENTRY(v7_dma_flush_range)
dcache_line_size r2, r3
sub r3, r2, #1
bic r0, r0, r3
1:
mcr p15, 0, r0, c7, c14, 1 @ clean & invalidate D / U line
add r0, r0, r2
cmp r0, r1
blo 1b
dsb
mov pc, lr
ENDPROC(v7_dma_flush_range)
__INITDATA
.type v7_cache_fns, #object
ENTRY(v7_cache_fns)
.long v7_flush_kern_cache_all
.long v7_flush_user_cache_all
.long v7_flush_user_cache_range
.long v7_coherent_kern_range
.long v7_coherent_user_range
.long v7_flush_kern_dcache_page
.long v7_dma_inv_range
.long v7_dma_clean_range
.long v7_dma_flush_range
.size v7_cache_fns, . - v7_cache_fns
