/* SPDX-License-Identifier: GPL-2.0-only */
/*
* linux/arch/arm/mm/cache-v7.S
*
* Copyright (C) 2001 Deep Blue Solutions Ltd.
* Copyright (C) 2005 ARM Ltd.
*
* This is the "shell" of the ARMv7 processor support.
*/
#include <linux/linkage.h>
#include <linux/init.h>
#include <linux/cfi_types.h>
#include <asm/assembler.h>
#include <asm/errno.h>
#include <asm/unwind.h>
#include <asm/hardware/cache-b15-rac.h>
#include "proc-macros.S"
.arch armv7-a
#ifdef CONFIG_CPU_ICACHE_MISMATCH_WORKAROUND
.globl icache_size
.data
.align 2
icache_size:
.long 64
.text
#endif
/*
* The secondary kernel init calls v7_flush_dcache_all before it enables
* the L1; however, the L1 comes out of reset in an undefined state, so
* the clean + invalidate performed by v7_flush_dcache_all causes a bunch
* of cache lines with uninitialized data and uninitialized tags to get
* written out to memory, which does really unpleasant things to the main
* processor. We fix this by performing an invalidate, rather than a
* clean + invalidate, before jumping into the kernel.
*
* This function needs to be called for both secondary cores startup and
* primary core resume procedures.
*/
ENTRY(v7_invalidate_l1)
mov r0, #0
mcr p15, 2, r0, c0, c0, 0 @ select L1 data cache in CSSELR
isb
mrc p15, 1, r0, c0, c0, 0 @ read cache geometry from CCSIDR
movw r3, #0x3ff
and r3, r3, r0, lsr #3 @ 'Associativity' in CCSIDR[12:3]
clz r1, r3 @ WayShift
mov r2, #1
mov r3, r3, lsl r1 @ NumWays-1 shifted into bits [31:...]
movs r1, r2, lsl r1 @ #1 shifted left by same amount
moveq r1, #1 @ r1 needs value > 0 even if only 1 way
and r2, r0, #0x7
add r2, r2, #4 @ SetShift
1: movw ip, #0x7fff
and r0, ip, r0, lsr #13 @ 'NumSets' in CCSIDR[27:13]
2: mov ip, r0, lsl r2 @ NumSet << SetShift
orr ip, ip, r3 @ Reg = (Temp<<WayShift)|(NumSets<<SetShift)
mcr p15, 0, ip, c7, c6, 2
subs r0, r0, #1 @ Set--
bpl 2b
subs r3, r3, r1 @ Way--
bcc 3f
mrc p15, 1, r0, c0, c0, 0 @ re-read cache geometry from CCSIDR
b 1b
3: dsb st
isb
ret lr
ENDPROC(v7_invalidate_l1)
/*
* v7_flush_icache_all()
*
* Flush the whole I-cache.
*
* Registers:
* r0 - set to 0
*/
SYM_TYPED_FUNC_START(v7_flush_icache_all)
mov r0, #0
ALT_SMP(mcr p15, 0, r0, c7, c1, 0) @ invalidate I-cache inner shareable
ALT_UP(mcr p15, 0, r0, c7, c5, 0) @ I+BTB cache invalidate
ret lr
SYM_FUNC_END(v7_flush_icache_all)
/*
* v7_flush_dcache_louis()
*
* Flush the D-cache up to the Level of Unification Inner Shareable
*
* Corrupted registers: r0-r6, r9-r10
*/
ENTRY(v7_flush_dcache_louis)
dmb @ ensure ordering with previous memory accesses
mrc p15, 1, r0, c0, c0, 1 @ read clidr, r0 = clidr
ALT_SMP(mov r3, r0, lsr #20) @ move LoUIS into position
ALT_UP( mov r3, r0, lsr #26) @ move LoUU into position
ands r3, r3, #7 << 1 @ extract LoU*2 field from clidr
bne start_flush_levels @ LoU != 0, start flushing
#ifdef CONFIG_ARM_ERRATA_643719
ALT_SMP(mrc p15, 0, r2, c0, c0, 0) @ read main ID register
ALT_UP( ret lr) @ LoUU is zero, so nothing to do
movw r1, #:lower16:(0x410fc090 >> 4) @ ID of ARM Cortex A9 r0p?
movt r1, #:upper16:(0x410fc090 >> 4)
teq r1, r2, lsr #4 @ test for errata affected core and if so...
moveq r3, #1 << 1 @ fix LoUIS value
beq start_flush_levels @ start flushing cache levels
#endif
ret lr
ENDPROC(v7_flush_dcache_louis)
/*
* v7_flush_dcache_all()
*
* Flush the whole D-cache.
*
* Corrupted registers: r0-r6, r9-r10
*
* - 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
mov r3, r0, lsr #23 @ move LoC into position
ands r3, r3, #7 << 1 @ extract LoC*2 from clidr
beq finished @ if loc is 0, then no need to clean
start_flush_levels:
mov r10, #0 @ start clean at cache level 0
flush_levels:
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
#ifdef CONFIG_PREEMPTION
save_and_disable_irqs_notrace r9 @ make cssr&csidr read atomic
#endif
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
#ifdef CONFIG_PREEMPTION
restore_irqs_notrace r9
#endif
and r2, r1, #7 @ extract the length of the cache lines
add r2, r2, #4 @ add 4 (line length offset)
movw 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
movw r6, #0x7fff
and r1, r6, r1, lsr #13 @ extract max number of the index size
mov r6, #1
movne r4, r4, lsl r5 @ # of ways shifted into bits [31:...]
movne r6, r6, lsl r5 @ 1 shifted left by same amount
loop1:
mov r9, r1 @ create working copy of max index
loop2:
mov r5, r9, lsl r2 @ factor set number into r5
orr r5, r5, r4 @ factor way number into r5
orr r5, r5, r10 @ factor cache level into r5
mcr p15, 0, r5, c7, c14, 2 @ clean & invalidate by set/way
subs r9, r9, #1 @ decrement the index
bge loop2
subs r4, r4, r6 @ decrement the way
bcs loop1
skip:
add r10, r10, #2 @ increment cache number
cmp r3, r10
#ifdef CONFIG_ARM_ERRATA_814220
dsb
#endif
bgt flush_levels
finished:
mov r10, #0 @ switch back to cache level 0
mcr p15, 2, r10, c0, c0, 0 @ select current cache level in cssr
dsb st
isb
ret 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
* maintenance instructions.
* The instruction cache can still be invalidated back to the point of
* unification in a single instruction.
*
*/
SYM_TYPED_FUNC_START(v7_flush_kern_cache_all)
stmfd sp!, {r4-r6, r9-r10, lr}
bl v7_flush_dcache_all
mov r0, #0
ALT_SMP(mcr p15, 0, r0, c7, c1, 0) @ invalidate I-cache inner shareable
ALT_UP(mcr p15, 0, r0, c7, c5, 0) @ I+BTB cache invalidate
ldmfd sp!, {r4-r6, r9-r10, lr}
ret lr
SYM_FUNC_END(v7_flush_kern_cache_all)
/*
* v7_flush_kern_cache_louis(void)
*
* Flush the data cache up to Level of Unification Inner Shareable.
* Invalidate the I-cache to the point of unification.
*/
SYM_TYPED_FUNC_START(v7_flush_kern_cache_louis)
stmfd sp!, {r4-r6, r9-r10, lr}
bl v7_flush_dcache_louis
mov r0, #0
ALT_SMP(mcr p15, 0, r0, c7, c1, 0) @ invalidate I-cache inner shareable
ALT_UP(mcr p15, 0, r0, c7, c5, 0) @ I+BTB cache invalidate
ldmfd sp!, {r4-r6, r9-r10, lr}
ret lr
SYM_FUNC_END(v7_flush_kern_cache_louis)
/*
* v7_flush_cache_all()
*
* Flush all TLB entries in a particular address space
*
* - mm - mm_struct describing address space
*/
SYM_TYPED_FUNC_START(v7_flush_user_cache_all)
ret lr
SYM_FUNC_END(v7_flush_user_cache_all)
/*
* 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.
*/
SYM_TYPED_FUNC_START(v7_flush_user_cache_range)
ret lr
SYM_FUNC_END(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
*/
SYM_TYPED_FUNC_START(v7_coherent_kern_range)
#ifdef CONFIG_CFI_CLANG /* Fallthrough if !CFI */
b v7_coherent_user_range
#endif
SYM_FUNC_END(v7_coherent_kern_range)
/*
* 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
*/
SYM_TYPED_FUNC_START(v7_coherent_user_range)
UNWIND(.fnstart )
dcache_line_size r2, r3
sub r3, r2, #1
bic r12, r0, r3
#ifdef CONFIG_ARM_ERRATA_764369
ALT_SMP(W(dsb))
ALT_UP(W(nop))
#endif
1:
USER( mcr p15, 0, r12, c7, c11, 1 ) @ clean D line to the point of unification
add r12, r12, r2
cmp r12, r1
blo 1b
dsb ishst
#ifdef CONFIG_CPU_ICACHE_MISMATCH_WORKAROUND
ldr r3, =icache_size
ldr r2, [r3, #0]
#else
icache_line_size r2, r3
#endif
sub r3, r2, #1
bic r12, r0, r3
2:
USER( mcr p15, 0, r12, c7, c5, 1 ) @ invalidate I line
add r12, r12, r2
cmp r12, r1
blo 2b
mov r0, #0
ALT_SMP(mcr p15, 0, r0, c7, c1, 6) @ invalidate BTB Inner Shareable
ALT_UP(mcr p15, 0, r0, c7, c5, 6) @ invalidate BTB
dsb ishst
isb
ret lr
/*
* Fault handling for the cache operation above. If the virtual address in r0
* isn't mapped, fail with -EFAULT.
*/
9001:
#ifdef CONFIG_ARM_ERRATA_775420
dsb
#endif
mov r0, #-EFAULT
ret lr
UNWIND(.fnend )
SYM_FUNC_END(v7_coherent_user_range)
/*
* v7_flush_kern_dcache_area(void *addr, size_t size)
*
* Ensure that the data held in the page kaddr is written back
* to the page in question.
*
* - addr - kernel address
* - size - region size
*/
SYM_TYPED_FUNC_START(v7_flush_kern_dcache_area)
dcache_line_size r2, r3
add r1, r0, r1
sub r3, r2, #1
bic r0, r0, r3
#ifdef CONFIG_ARM_ERRATA_764369
ALT_SMP(W(dsb))
ALT_UP(W(nop))
#endif
1:
mcr p15, 0, r0, c7, c14, 1 @ clean & invalidate D line / unified line
add r0, r0, r2
cmp r0, r1
blo 1b
dsb st
ret lr
SYM_FUNC_END(v7_flush_kern_dcache_area)
/*
* 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
*/
v7_dma_inv_range:
dcache_line_size r2, r3
sub r3, r2, #1
tst r0, r3
bic r0, r0, r3
#ifdef CONFIG_ARM_ERRATA_764369
ALT_SMP(W(dsb))
ALT_UP(W(nop))
#endif
mcrne p15, 0, r0, c7, c14, 1 @ clean & invalidate D / U line
addne r0, r0, r2
tst r1, r3
bic r1, r1, r3
mcrne p15, 0, r1, c7, c14, 1 @ clean & invalidate D / U line
cmp r0, r1
1:
mcrlo p15, 0, r0, c7, c6, 1 @ invalidate D / U line
addlo r0, r0, r2
cmplo r0, r1
blo 1b
dsb st
ret lr
ENDPROC(v7_dma_inv_range)
/*
* v7_dma_clean_range(start,end)
* - start - virtual start address of region
* - end - virtual end address of region
*/
v7_dma_clean_range:
dcache_line_size r2, r3
sub r3, r2, #1
bic r0, r0, r3
#ifdef CONFIG_ARM_ERRATA_764369
ALT_SMP(W(dsb))
ALT_UP(W(nop))
#endif
1:
mcr p15, 0, r0, c7, c10, 1 @ clean D / U line
add r0, r0, r2
cmp r0, r1
blo 1b
dsb st
ret lr
ENDPROC(v7_dma_clean_range)
/*
* v7_dma_flush_range(start,end)
* - start - virtual start address of region
* - end - virtual end address of region
*/
SYM_TYPED_FUNC_START(v7_dma_flush_range)
dcache_line_size r2, r3
sub r3, r2, #1
bic r0, r0, r3
#ifdef CONFIG_ARM_ERRATA_764369
ALT_SMP(W(dsb))
ALT_UP(W(nop))
#endif
1:
mcr p15, 0, r0, c7, c14, 1 @ clean & invalidate D / U line
add r0, r0, r2
cmp r0, r1
blo 1b
dsb st
ret lr
SYM_FUNC_END(v7_dma_flush_range)
/*
* dma_map_area(start, size, dir)
* - start - kernel virtual start address
* - size - size of region
* - dir - DMA direction
*/
SYM_TYPED_FUNC_START(v7_dma_map_area)
add r1, r1, r0
teq r2, #DMA_FROM_DEVICE
beq v7_dma_inv_range
b v7_dma_clean_range
SYM_FUNC_END(v7_dma_map_area)
/*
* dma_unmap_area(start, size, dir)
* - start - kernel virtual start address
* - size - size of region
* - dir - DMA direction
*/
SYM_TYPED_FUNC_START(v7_dma_unmap_area)
add r1, r1, r0
teq r2, #DMA_TO_DEVICE
bne v7_dma_inv_range
ret lr
SYM_FUNC_END(v7_dma_unmap_area)
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