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MAX_CARLINK_A270S/A27-STEPLDR/Src/cp15_asm_iar.s

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ArmAsm

/* ----------------------------------------------------------------------------
* SAM Software Package License
* ----------------------------------------------------------------------------
* Copyright (c) 2012, Atmel Corporation
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the disclaimer below.
*
* Atmel's name may not be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
* DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES// LOSS OF USE, DATA,
* OR PROFITS// OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
* ----------------------------------------------------------------------------
*/
/** \file */
/**
* \addtogroup cp15_cache Cache Operations
*
* \section Usage
*
* They are performed as MCR instructions and only operate on a level 1 cache associated with
* ATM v7 processor.
* The supported operations are:
* <ul>
* <li> Any of these operations can be applied to
* -# any data cache
* -# any unified cache.
* <li> Invalidate by MVA
* Performs an invalidate of a data or unified cache line based on the address it contains.
* <li> Invalidate by set/way
* Performs an invalidate of a data or unified cache line based on its location in the cache hierarchy.
* <li> Clean by MVA
* Performs a clean of a data or unified cache line based on the address it contains.
* <li> Clean by set/way
* Performs a clean of a data or unified cache line based on its location in the cache hierarchy.
* <li> Clean and Invalidate by MVA
* Performs a clean and invalidate of a data or unified cache line based on the address it contains.
* <li> Clean and Invalidate by set/way
* Performs a clean and invalidate of a data or unified cache line based on its location in the cache hierarchy.
* </ul>
*
* Related files:\n
* \ref cp15.h\n
* \ref cp15_arm_iar.s \n
*/
MODULE ?cp15
//// Forward declaration of sections.
SECTION IRQ_STACK:DATA:NOROOT(2)
SECTION CSTACK:DATA:NOROOT(3)
/*----------------------------------------------------------------------------
* Headers
*----------------------------------------------------------------------------*/
#define __ASSEMBLY__
/*----------------------------------------------------------------------------
* Functions to access CP15 coprocessor register
*----------------------------------------------------------------------------*/
PUBLIC CP15_ReadID
PUBLIC CP15_ExclusiveCache
PUBLIC CP15_NonExclusiveCache
PUBLIC CP15_ISB
PUBLIC CP15_DSB
PUBLIC CP15_DMB
PUBLIC CP15_SelectICache
PUBLIC CP15_SelectDCache
PUBLIC CP15_ReadControl
PUBLIC CP15_WriteControl
PUBLIC CP15_WriteDomainAccessControl
PUBLIC CP15_WriteTTB
PUBLIC CP15_InvalidateIcacheInnerSharable
PUBLIC CP15_InvalidateBTBinnerSharable
PUBLIC CP15_InvalidateIcache
PUBLIC CP15_InvalidateIcacheByMva
PUBLIC CP15_InvalidateBTB
PUBLIC CP15_InvalidateBTBbyMva
PUBLIC CP15_InvalidateDcacheBySetWay
PUBLIC CP15_CleanDCacheBySetWay
PUBLIC CP15_CleanInvalidateDCacheBySetWay
PUBLIC CP15_InvalidateDcacheByMva
PUBLIC CP15_CleanDCacheByMva
PUBLIC CP15_CleanDCacheUMva
PUBLIC CP15_CleanInvalidateDcacheByMva
PUBLIC CP15_InvalidateTranslationTable
PUBLIC CP15_coherent_dcache_for_dma
PUBLIC CP15_invalidate_dcache_for_dma
PUBLIC CP15_clean_dcache_for_dma
PUBLIC CP15_flush_dcache_for_dma
PUBLIC CP15_flush_kern_dcache_for_dma
/**
* \brief Register c0 accesses the ID Register, Cache Type Register, and TCM Status Registers.
* Reading from this register returns the device ID, the cache type, or the TCM status
* depending on the value of Opcode_2 used.
*/
SECTION .CP15_ReadID:DATA:NOROOT(2)
PUBLIC CP15_ReadID
CP15_ReadID:
mov r0, #0
mrc p15, 0, r0, c0, c0, 0
bx lr
/**
* \brief Register c7 accesses the ACTLR Register, to indicate cpu that L2 is in exclusive mode
*/
SECTION .CP15_ISB:DATA:NOROOT(2)
PUBLIC CP15_ISB
CP15_ISB:
mov r0, #0
mcr p15, 0, r0, c7, c5, 4
nop
bx lr
/**
* \brief Register c7 accesses the ACTLR Register, to indicate cpu that L2 is in exclusive mode
*/
SECTION .CP15_DSB:DATA:NOROOT(2)
PUBLIC CP15_DSB
CP15_DSB:
mov r0, #0
mcr p15, 0, r0, c7, c10, 4
nop
bx lr
/**
* \brief Register c7 accesses the ACTLR Register, to indicate cpu that L2 is in exclusive mode
*/
SECTION .CP15_DMB:DATA:NOROOT(2)
PUBLIC CP15_DMB
CP15_DMB:
mov r0, #0
mcr p15, 0, r0, c7, c10, 5
nop
bx lr
/**
* \brief Register c1 accesses the ACTLR Register, to indicate cpu that L2 is in exclusive mode
*/
SECTION .CP15_ExclusiveCache:DATA:NOROOT(2)
PUBLIC CP15_ExclusiveCache
CP15_ExclusiveCache:
mov r0, #0
mrc p15, 0, r0, c1, c0, 1 ; Read ACTLR
orr r0, r0, #0x00000080
mcr p15, 0, r0, c1, c0, 1 ; Write ACTLR
nop
bx lr
/**
* \brief Register c1 accesses the ACTLR Register, to indicate cpu that L2 is in exclusive mode
*/
SECTION .CP15_NonExclusiveCache:DATA:NOROOT(2)
PUBLIC CP15_NonExclusiveCache
CP15_NonExclusiveCache:
mov r0, #0
mrc p15, 0, r0, c1, c0, 1 ; Read ACTLR
bic r0, r0, #0x00000080
mcr p15, 0, r0, c1, c0, 1 ; Write ACTLR
nop
bx lr
/**
* \brief Register c1 accesses the CSSELR Register, to select ICache
*/
SECTION .CP15_SelectICache:DATA:NOROOT(2)
PUBLIC CP15_SelectICache
CP15_SelectICache:
mrc p15, 2, r0, c0, c0, 0 ; Read CSSELR
orr r0, r0, #0x1 ; Change 0th bit to ICache
mcr p15, 2, r0, c0, c0, 0 ; Write CSSELR
nop
bx lr
/**
* \brief Register c1 accesses the CSSELR Register, to select DCache
*/
SECTION .CP15_SelectDCache:DATA:NOROOT(2)
PUBLIC CP15_SelectDCache
CP15_SelectDCache:
mrc p15, 2, r0, c0, c0, 0 ; Read CSSELR
and r0, r0, #0xFFFFFFFE ; Change 0th bit to ICache
mcr p15, 2, r0, c0, c0, 0 ; Write CSSELR
nop
bx lr
/**
* \brief Register c1 is the Control Register for the ARM926EJ-S processor.
* This register specifies the configuration used to enable and disable the
* caches and MMU. It is recommended that you access this register using a
* read-modify-write sequence
*/
SECTION .CP15_ReadControl:CODE:NOROOT(2)
PUBLIC CP15_ReadControl
CP15_ReadControl:
mov r0, #0
mrc p15, 0, r0, c1, c0, 0
bx lr
SECTION .CP15_WriteControl:CODE:NOROOT(2)
PUBLIC CP15_WriteControl
CP15_WriteControl:
mcr p15, 0, r0, c1, c0, 0
dsb
isb
bx lr
SECTION .CP15_WriteDomainAccessControl:CODE:NOROOT(2)
PUBLIC CP15_WriteDomainAccessControl
CP15_WriteDomainAccessControl:
mcr p15, 0, r0, c3, c0, 0
dsb
isb
bx lr
/**
* \brief ARMv7A architecture supports two translation tables
* Configure translation table base (TTB) control register cp15,c2
* to a value of all zeros, indicates we are using TTB register 0.
* write the address of our page table base to TTB register 0.
*/
SECTION .CP15_WriteTTB:CODE:NOROOT(2)
PUBLIC CP15_WriteTTB
CP15_WriteTTB:
mcr p15, 0, r0, c2, c0, 0
dsb
isb
bx lr
/**
* \brief Invalidate I cache predictor array inner Sharable
*/
SECTION .CP15_InvalidateIcacheInnerSharable:CODE:NOROOT(2)
PUBLIC CP15_InvalidateIcacheInnerSharable
CP15_InvalidateIcacheInnerSharable:
mov r0, #0
mcr p15, 0, r0, c7, c1, 0
bx lr
/**
* \brief Invalidate entire branch predictor array inner Sharable
*/
SECTION .CP15_InvalidateBTBinnerSharable:CODE:NOROOT(2)
PUBLIC CP15_InvalidateBTBinnerSharable
CP15_InvalidateBTBinnerSharable:
mov r0, #0
mcr p15, 0, r0, c7, c1, 6
bx lr
/**
* \brief Invalidate all instruction caches to PoU, also flushes branch target cache
*/
SECTION .CP15_InvalidateIcache:CODE:NOROOT(2)
PUBLIC CP15_InvalidateIcache
CP15_InvalidateIcache:
mov r0, #0
mcr p15, 0, r0, c7, c5, 0
isb
bx lr
/**
* \brief Invalidate instruction caches by VA to PoU
*/
SECTION .CP15_InvalidateIcacheByMva:CODE:NOROOT(2)
PUBLIC CP15_InvalidateIcacheByMva
CP15_InvalidateIcacheByMva:
mov r0, #0
mcr p15, 0, r0, c7, c5, 1
bx lr
/**
* \brief Invalidate entire branch predictor array
*/
SECTION .CP15_InvalidateBTB:CODE:NOROOT(2)
PUBLIC CP15_InvalidateBTB
CP15_InvalidateBTB:
mov r0, #0
mcr p15, 0, r0, c7, c5, 6
dsb
isb
bx lr
/**
* \brief Invalidate branch predictor array entry by MVA
*/
SECTION .CP15_InvalidateBTBbyMva:CODE:NOROOT(2)
PUBLIC CP15_InvalidateBTBbyMva
CP15_InvalidateBTBbyMva:
mcr p15, 0, r0, c7, c5, 7
bx lr
/***********************************************************
*
* ===Data Cache related maintenance functions===
*
**************************************************************/
// ===Data Cache maintenance by SetWay ===
/**
* \brief Invalidate entire data cache by set/way
*/
SECTION .CP15_InvalidateDcacheBySetWay:CODE:NOROOT(2)
PUBLIC CP15_InvalidateDcacheBySetWay
CP15_InvalidateDcacheBySetWay:
MRC p15, 1, r0, c0, c0, 1 ; Read CLIDR
ANDS r3, r0, #0x07000000 ; Extract coherency level
MOV r3, r3, LSR #23 ; Total cache levels << 1
BEQ inv_finish ; If 0, no need to clean
MOV r10, #0 ; R10 holds current cache level << 1
inv_cache_level_loop
ADD r2, r10, r10, LSR #1 ; R2 holds cache "Set" position
MOV r1, r0, LSR r2 ; Bottom 3 bits are the Cache-type for this level
AND r1, r1, #7 ; Isolate those lower 3 bits
CMP r1, #2
BLT inv_skip ; No cache or only instruction cache at this level
MCR p15, 2, r10, c0, c0, 0 ; Write the Cache Size selection register
ISB ; ISB to sync the change to the CacheSizeID reg
MRC p15, 1, r1, c0, c0, 0 ; Reads current Cache Size ID register
AND r2, r1, #7 ; Extract the line length field
ADD r2, r2, #4 ; Add 4 for the line length offset (log2 16 bytes)
LDR r4, =0x3FF
ANDS r4, r4, r1, LSR #3 ; R4 is the max number on the way size (right aligned)
CLZ r5, r4 ; R5 is the bit position of the way size increment
LDR r7, =0x7FFF
ANDS r7, r7, r1, LSR #13 ; R7 is the max number of the index size (right aligned)
inv_set_loop
MOV r9, r4 ; R9 working copy of the max way size (right aligned)
inv_way_loop
ORR r11, r10, r9, LSL r5 ; Factor in the Way number and cache number into R11
ORR r11, r11, r7, LSL r2 ; Factor in the Set number
MCR p15, 0, r11, c7, c6, 2 ; Invalidate by Set/Way
SUBS r9, r9, #1 ; Decrement the Way number
BGE inv_way_loop
SUBS r7, r7, #1 ; Decrement the Set number
BGE inv_set_loop
inv_skip
ADD r10, r10, #2 ; increment the cache number
CMP r3, r10
BGT inv_cache_level_loop
inv_finish
NOP
BX lr
/**
* \brief Clean entire data cache by set/way
*/
SECTION .CP15_CleanDCacheBySetWay:CODE:NOROOT(2)
PUBLIC CP15_CleanDCacheBySetWay
CP15_CleanDCacheBySetWay:
MRC p15, 1, r0, c0, c0, 1 ; Read CLIDR
ANDS r3, r0, #0x07000000 ; Extract coherency level
MOV r3, r3, LSR #23 ; Total cache levels << 1
BEQ clean_finish ; If 0, no need to clean
MOV r10, #0 ; R10 holds current cache level << 1
clean_cache_level_loop
ADD r2, r10, r10, LSR #1 ; R2 holds cache "Set" position
MOV r1, r0, LSR r2 ; Bottom 3 bits are the Cache-type for this level
AND r1, r1, #7 ; Isolate those lower 3 bits
CMP r1, #2
BLT clean_skip ; No cache or only instruction cache at this level
MCR p15, 2, r10, c0, c0, 0 ; Write the Cache Size selection register
ISB ; ISB to sync the change to the CacheSizeID reg
MRC p15, 1, r1, c0, c0, 0 ; Reads current Cache Size ID register
AND r2, r1, #7 ; Extract the line length field
ADD r2, r2, #4 ; Add 4 for the line length offset (log2 16 bytes)
LDR r4, =0x3FF
ANDS r4, r4, r1, LSR #3 ; R4 is the max number on the way size (right aligned)
CLZ r5, r4 ; R5 is the bit position of the way size increment
LDR r7, =0x7FFF
ANDS r7, r7, r1, LSR #13 ; R7 is the max number of the index size (right aligned)
clean_set_loop
MOV r9, r4 ; R9 working copy of the max way size (right aligned)
clean_way_loop
ORR r11, r10, r9, LSL r5 ; Factor in the Way number and cache number into R11
ORR r11, r11, r7, LSL r2 ; Factor in the Set number
MCR p15, 0, r11, c7, c10, 2 ; Clean by Set/Way
SUBS r9, r9, #1 ; Decrement the Way number
BGE clean_way_loop
SUBS r7, r7, #1 ; Decrement the Set number
BGE clean_set_loop
clean_skip
ADD r10, r10, #2 ; increment the cache number
CMP r3, r10
BGT clean_cache_level_loop
clean_finish
NOP
BX lr
/**
* \brief Clean and Invalidate entire data cache by set/way
*/
SECTION .CP15_CleanInvalidateDCacheBySetWay:CODE:NOROOT(2)
PUBLIC CP15_CleanInvalidateDCacheBySetWay
CP15_CleanInvalidateDCacheBySetWay:
MRC p15, 1, r0, c0, c0, 1 ; Read CLIDR
ANDS r3, r0, #0x07000000 ; Extract coherency level
MOV r3, r3, LSR #23 ; Total cache levels << 1
BEQ clinv_finish ; If 0, no need to clean
MOV r10, #0 ; R10 holds current cache level << 1
clinv_cache_level_loop
ADD r2, r10, r10, LSR #1 ; R2 holds cache "Set" position
MOV r1, r0, LSR r2 ; Bottom 3 bits are the Cache-type for this level
AND r1, r1, #7 ; Isolate those lower 3 bits
CMP r1, #2
BLT clean_skip ; No cache or only instruction cache at this level
MCR p15, 2, r10, c0, c0, 0 ; Write the Cache Size selection register
ISB ; ISB to sync the change to the CacheSizeID reg
MRC p15, 1, r1, c0, c0, 0 ; Reads current Cache Size ID register
AND r2, r1, #7 ; Extract the line length field
ADD r2, r2, #4 ; Add 4 for the line length offset (log2 16 bytes)
LDR r4, =0x3FF
ANDS r4, r4, r1, LSR #3 ; R4 is the max number on the way size (right aligned)
CLZ r5, r4 ; R5 is the bit position of the way size increment
LDR r7, =0x7FFF
ANDS r7, r7, r1, LSR #13 ; R7 is the max number of the index size (right aligned)
clinv_set_loop
MOV r9, r4 ; R9 working copy of the max way size (right aligned)
clinv_way_loop
ORR r11, r10, r9, LSL r5 ; Factor in the Way number and cache number into R11
ORR r11, r11, r7, LSL r2 ; Factor in the Set number
MCR p15, 0, r11, c7, c14, 2 ; Clean and Invalidate by Set/Way
SUBS r9, r9, #1 ; Decrement the Way number
BGE clean_way_loop
SUBS r7, r7, #1 ; Decrement the Set number
BGE clean_set_loop
clinv_skip
ADD r10, r10, #2 ; increment the cache number
CMP r3, r10
BGT clean_cache_level_loop
clinv_finish
NOP
BX lr
// ===Data Cache maintenance by VA ===
/**
* \brief Invalidate data cache by VA to Poc
*/
SECTION .CP15_InvalidateDcacheByMva:CODE:NOROOT(2)
PUBLIC CP15_InvalidateDcacheByMva
CP15_InvalidateDcacheByMva:
mov r2, #0x20 ;Eight words per line, Cortex-A5 L1 Line Size 32 Bytes
mov r3, r0
inv_loop
mcr p15, 0, r0, c7, c6, 1
add r3, r3, r2
cmp r3, r1
bls inv_loop
bx lr
/**
* \brief Clean data cache by MVA
*/
SECTION .CP15_CleanDCacheByMva:CODE:NOROOT(2)
PUBLIC CP15_CleanDCacheByMva
CP15_CleanDCacheByMva:
mov r2, #0x20 ;Eight words per line, Cortex-A5 L1 Line Size 32 Bytes
mov r3, r0
clean_loop
mcr p15, 0, r0, c7, c10, 1
add r3, r3, r2
cmp r3, r1
bls clean_loop
bx lr
/**
* \brief Clean unified cache by MVA
*/
SECTION .CP15_CleanDCacheUMva:CODE:NOROOT(2)
PUBLIC CP15_CleanDCacheUMva
CP15_CleanDCacheUMva:
mov r0, #0
mcr p15, 0, r0, c7, c11, 1
bx lr
/**
* \brief Clean and invalidate data cache by VA to PoC
*/
SECTION .CP15_CleanInvalidateDcacheByMva:CODE:NOROOT(2)
PUBLIC CP15_CleanInvalidateDcacheByMva
CP15_CleanInvalidateDcacheByMva:
mov r2, #0x20 ;Eight words per line, Cortex-A5 L1 Line Size 32 Bytes
mov r3, r0
clinv_loop
mcr p15, 0, r0, c7, c14, 1
add r3, r3, r2
cmp r3, r1
bls clinv_loop
bx lr
/**
* \brief Invalidate translation table
*/
SECTION .CP15_InvalidateTranslationTable:CODE:NOROOT(2)
PUBLIC CP15_InvalidateTranslationTable
CP15_InvalidateTranslationTable:
mov r0, #0
mcr p15, 0, r0, c8, c3, 0
dsb
isb
mcr p15, 0, r0, c8, c7, 0
dsb
isb
bx lr
/**
* \brief flush translation table
*/
SECTION .CP15_FlushTranslationTable:CODE:NOROOT(2)
PUBLIC CP15_FlushTranslationTable
CP15_FlushTranslationTable:
mov r0, #0
mcr p15, 0, r0, c8, c3, 0
dsb
isb
bx lr
/**
* \brief 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.
* \param start virtual start address of region
* \param end virtual end address of region
*/
SECTION .CP15_coherent_dcache_for_dma:CODE:NOROOT(2)
PUBLIC CP15_coherent_dcache_for_dma
CP15_coherent_dcache_for_dma:
// dcache_line_size r2, r3
mrc p15, 0, r3, c0, c0, 1 // read ctr
lsr r3, r3, #16
and r3, r3, #0xf // cache line size encoding
mov r2, #4 // bytes per word
mov r2, r2, lsl r3 // actual cache line size
sub r3, r2, #1
bic r12, r0, r3
loop1:
mcr p15, 0, r12, c7, c11, 1 // clean D line to the point of unification
add r12, r12, r2
cmp r12, r1
blo loop1
dsb
// .macro icache_line_size, reg, tmp
mrc p15, 0, r3, c0, c0, 1 // read ctr
and r3, r3, #0xf // cache line size encoding
mov r2, #4 // bytes per word
mov r2, r2, lsl r3 // actual cache line size
sub r3, r2, #1
bic r12, r0, r3
loop2:
mcr p15, 0, r12, c7, c5, 1 // invalidate I line
add r12, r12, r2
cmp r12, r1
blo loop2
mov r0, #0
mcr p15, 0, r0, c7, c1, 6 //invalidate BTB Inner Shareable
mcr p15, 0, r0, c7, c5, 6 // invalidate BTB
dsb
isb
bx lr
/**
* \brief 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.
* \param start virtual start address of region
* \param end virtual end address of region
*/
SECTION .CP15_invalidate_dcache_for_dma:CODE:NOROOT(2)
PUBLIC CP15_invalidate_dcache_for_dma
CP15_invalidate_dcache_for_dma:
// dcache_line_size r2, r3
mrc p15, 0, r3, c0, c0, 1 // read ctr
lsr r3, r3, #16
and r3, r3, #0xf // cache line size encoding
mov r2, #4 // bytes per word
mov r2, r2, lsl r3 // actual cache line size
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
loop3:
mcr p15, 0, r0, c7, c6, 1 // invalidate D / U line
add r0, r0, r2
cmp r0, r1
blo loop3
dsb
bx lr
/**
* \brief Clean the data cache within the specified region
* \param start virtual start address of region
* \param end virtual end address of region
*/
SECTION .CP15_clean_dcache_for_dma:CODE:NOROOT(2)
PUBLIC CP15_clean_dcache_for_dma
CP15_clean_dcache_for_dma:
// dcache_line_size r2, r3
mrc p15, 0, r3, c0, c0, 1 // read ctr
lsr r3, r3, #16
and r3, r3, #0xf // cache line size encoding
mov r2, #4 // bytes per word
mov r2, r2, lsl r3 // actual cache line size
sub r3, r2, #1
bic r0, r0, r3
loop4:
mcr p15, 0, r0, c7, c10, 1 // clean D / U line
add r0, r0, r2
cmp r0, r1
blo loop4
dsb
bx lr
/**
* \brief Flush the data cache within the specified region
* \param start virtual start address of region
* \param end virtual end address of region
*/
SECTION .CP15_flush_dcache_for_dma:CODE:NOROOT(2)
PUBLIC CP15_flush_dcache_for_dma
CP15_flush_dcache_for_dma:
// dcache_line_size r2, r3
mrc p15, 0, r3, c0, c0, 1 // read ctr
lsr r3, r3, #16
and r3, r3, #0xf // cache line size encoding
mov r2, #4 // bytes per word
mov r2, r2, lsl r3 // actual cache line size
sub r3, r2, #1
bic r0, r0, r3
loop5:
mcr p15, 0, r0, c7, c14, 1 // clean & invalidate D / U line
add r0, r0, r2
cmp r0, r1
blo loop5
dsb
bx lr
/**
* \brief CP15_flush_kern_dcache_for_dma
* Ensure that the data held in the page kaddr is written back to the page in question.
* \param start virtual start address of region
* \param end virtual end address of region
*/
SECTION .CP15_flush_kern_dcache_for_dma:CODE:NOROOT(2)
PUBLIC CP15_flush_kern_dcache_for_dma
CP15_flush_kern_dcache_for_dma:
// dcache_line_size r2, r3
mrc p15, 0, r3, c0, c0, 1 // read ctr
lsr r3, r3, #16
and r3, r3, #0xf // cache line size encoding
mov r2, #4 // bytes per word
mov r2, r2, lsl r3 // actual cache line size
add r1, r0, r1
sub r3, r2, #1
bic r0, r0, r3
mcr p15, 0, r0, c7, c14, 1 // clean & invalidate D line / unified line
add r0, r0, r2
cmp r0, r1
blo 1b
dsb
bx lr
END