linux_dsm_epyc7002/arch/arm64/mm/cache.S
Ashok Kumar 0a28714c53 arm64: Use PoU cache instr for I/D coherency
In systems with three levels of cache(PoU at L1 and PoC at L3),
PoC cache flush instructions flushes L2 and L3 caches which could affect
performance.
For cache flushes for I and D coherency, PoU should suffice.
So changing all I and D coherency related cache flushes to PoU.

Introduced a new __clean_dcache_area_pou API for dcache flush till PoU
and provided a common macro for __flush_dcache_area and
__clean_dcache_area_pou.

Also, now in __sync_icache_dcache, icache invalidation for non-aliasing
VIPT icache is done only for that particular page instead of the earlier
__flush_icache_all.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ashok Kumar <ashoks@broadcom.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-12-17 11:07:13 +00:00

207 lines
4.6 KiB
ArmAsm

/*
* Cache maintenance
*
* Copyright (C) 2001 Deep Blue Solutions Ltd.
* Copyright (C) 2012 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 program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/errno.h>
#include <linux/linkage.h>
#include <linux/init.h>
#include <asm/assembler.h>
#include <asm/cpufeature.h>
#include <asm/alternative.h>
#include "proc-macros.S"
/*
* flush_icache_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
*/
ENTRY(flush_icache_range)
/* FALLTHROUGH */
/*
* __flush_cache_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
*/
ENTRY(__flush_cache_user_range)
dcache_line_size x2, x3
sub x3, x2, #1
bic x4, x0, x3
1:
USER(9f, dc cvau, x4 ) // clean D line to PoU
add x4, x4, x2
cmp x4, x1
b.lo 1b
dsb ish
icache_line_size x2, x3
sub x3, x2, #1
bic x4, x0, x3
1:
USER(9f, ic ivau, x4 ) // invalidate I line PoU
add x4, x4, x2
cmp x4, x1
b.lo 1b
dsb ish
isb
mov x0, #0
ret
9:
mov x0, #-EFAULT
ret
ENDPROC(flush_icache_range)
ENDPROC(__flush_cache_user_range)
/*
* __flush_dcache_area(kaddr, size)
*
* Ensure that any D-cache lines for the interval [kaddr, kaddr+size)
* are cleaned and invalidated to the PoC.
*
* - kaddr - kernel address
* - size - size in question
*/
ENTRY(__flush_dcache_area)
dcache_by_line_op civac, sy, x0, x1, x2, x3
ret
ENDPIPROC(__flush_dcache_area)
/*
* __clean_dcache_area_pou(kaddr, size)
*
* Ensure that any D-cache lines for the interval [kaddr, kaddr+size)
* are cleaned to the PoU.
*
* - kaddr - kernel address
* - size - size in question
*/
ENTRY(__clean_dcache_area_pou)
dcache_by_line_op cvau, ish, x0, x1, x2, x3
ret
ENDPROC(__clean_dcache_area_pou)
/*
* __inval_cache_range(start, end)
* - start - start address of region
* - end - end address of region
*/
ENTRY(__inval_cache_range)
/* FALLTHROUGH */
/*
* __dma_inv_range(start, end)
* - start - virtual start address of region
* - end - virtual end address of region
*/
__dma_inv_range:
dcache_line_size x2, x3
sub x3, x2, #1
tst x1, x3 // end cache line aligned?
bic x1, x1, x3
b.eq 1f
dc civac, x1 // clean & invalidate D / U line
1: tst x0, x3 // start cache line aligned?
bic x0, x0, x3
b.eq 2f
dc civac, x0 // clean & invalidate D / U line
b 3f
2: dc ivac, x0 // invalidate D / U line
3: add x0, x0, x2
cmp x0, x1
b.lo 2b
dsb sy
ret
ENDPIPROC(__inval_cache_range)
ENDPROC(__dma_inv_range)
/*
* __dma_clean_range(start, end)
* - start - virtual start address of region
* - end - virtual end address of region
*/
__dma_clean_range:
dcache_line_size x2, x3
sub x3, x2, #1
bic x0, x0, x3
1:
alternative_if_not ARM64_WORKAROUND_CLEAN_CACHE
dc cvac, x0
alternative_else
dc civac, x0
alternative_endif
add x0, x0, x2
cmp x0, x1
b.lo 1b
dsb sy
ret
ENDPROC(__dma_clean_range)
/*
* __dma_flush_range(start, end)
* - start - virtual start address of region
* - end - virtual end address of region
*/
ENTRY(__dma_flush_range)
dcache_line_size x2, x3
sub x3, x2, #1
bic x0, x0, x3
1: dc civac, x0 // clean & invalidate D / U line
add x0, x0, x2
cmp x0, x1
b.lo 1b
dsb sy
ret
ENDPIPROC(__dma_flush_range)
/*
* __dma_map_area(start, size, dir)
* - start - kernel virtual start address
* - size - size of region
* - dir - DMA direction
*/
ENTRY(__dma_map_area)
add x1, x1, x0
cmp w2, #DMA_FROM_DEVICE
b.eq __dma_inv_range
b __dma_clean_range
ENDPIPROC(__dma_map_area)
/*
* __dma_unmap_area(start, size, dir)
* - start - kernel virtual start address
* - size - size of region
* - dir - DMA direction
*/
ENTRY(__dma_unmap_area)
add x1, x1, x0
cmp w2, #DMA_TO_DEVICE
b.ne __dma_inv_range
ret
ENDPIPROC(__dma_unmap_area)