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author | Catalin Marinas <catalin.marinas@arm.com> | 2012-03-05 11:49:28 +0000 |
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committer | Catalin Marinas <catalin.marinas@arm.com> | 2012-09-17 13:42:00 +0100 |
commit | f1a0c4aa0937975b53991842a494f741d7769b02 (patch) | |
tree | 9b344c5267cb982b14a2372a0a20714f5b36d61a /arch/arm64/mm/cache.S | |
parent | 9cce7a435f89c9e60f244d44da2cf1cf4ed094ac (diff) | |
download | op-kernel-dev-f1a0c4aa0937975b53991842a494f741d7769b02.zip op-kernel-dev-f1a0c4aa0937975b53991842a494f741d7769b02.tar.gz |
arm64: Cache maintenance routines
The patch adds functionality required for cache maintenance. The AArch64
architecture mandates non-aliasing VIPT or PIPT D-cache and VIPT (may
have aliases) or ASID-tagged VIVT I-cache. Cache maintenance operations
are automatically broadcast in hardware between CPUs.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/arm64/mm/cache.S')
-rw-r--r-- | arch/arm64/mm/cache.S | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/arch/arm64/mm/cache.S b/arch/arm64/mm/cache.S new file mode 100644 index 0000000..abe69b8 --- /dev/null +++ b/arch/arm64/mm/cache.S @@ -0,0 +1,168 @@ +/* + * 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/linkage.h> +#include <linux/init.h> +#include <asm/assembler.h> + +#include "proc-macros.S" + +/* + * __flush_dcache_all() + * + * Flush the whole D-cache. + * + * Corrupted registers: x0-x7, x9-x11 + */ +ENTRY(__flush_dcache_all) + dsb sy // ensure ordering with previous memory accesses + mrs x0, clidr_el1 // read clidr + and x3, x0, #0x7000000 // extract loc from clidr + lsr x3, x3, #23 // left align loc bit field + cbz x3, finished // if loc is 0, then no need to clean + mov x10, #0 // start clean at cache level 0 +loop1: + add x2, x10, x10, lsr #1 // work out 3x current cache level + lsr x1, x0, x2 // extract cache type bits from clidr + and x1, x1, #7 // mask of the bits for current cache only + cmp x1, #2 // see what cache we have at this level + b.lt skip // skip if no cache, or just i-cache + save_and_disable_irqs x9 // make CSSELR and CCSIDR access atomic + msr csselr_el1, x10 // select current cache level in csselr + isb // isb to sych the new cssr&csidr + mrs x1, ccsidr_el1 // read the new ccsidr + restore_irqs x9 + and x2, x1, #7 // extract the length of the cache lines + add x2, x2, #4 // add 4 (line length offset) + mov x4, #0x3ff + and x4, x4, x1, lsr #3 // find maximum number on the way size + clz x5, x4 // find bit position of way size increment + mov x7, #0x7fff + and x7, x7, x1, lsr #13 // extract max number of the index size +loop2: + mov x9, x4 // create working copy of max way size +loop3: + lsl x6, x9, x5 + orr x11, x10, x6 // factor way and cache number into x11 + lsl x6, x7, x2 + orr x11, x11, x6 // factor index number into x11 + dc cisw, x11 // clean & invalidate by set/way + subs x9, x9, #1 // decrement the way + b.ge loop3 + subs x7, x7, #1 // decrement the index + b.ge loop2 +skip: + add x10, x10, #2 // increment cache number + cmp x3, x10 + b.gt loop1 +finished: + mov x10, #0 // swith back to cache level 0 + msr csselr_el1, x10 // select current cache level in csselr + dsb sy + isb + ret +ENDPROC(__flush_dcache_all) + +/* + * 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(flush_cache_all) + mov x12, lr + bl __flush_dcache_all + mov x0, #0 + ic ialluis // I+BTB cache invalidate + ret x12 +ENDPROC(flush_cache_all) + +/* + * 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 sy + + 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 +9: // ignore any faulting cache operation + dsb sy + isb + ret +ENDPROC(flush_icache_range) +ENDPROC(__flush_cache_user_range) + +/* + * __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 + * - size - size in question + */ +ENTRY(__flush_dcache_area) + dcache_line_size x2, x3 + add x1, x0, x1 + sub x3, x2, #1 + bic x0, x0, x3 +1: dc civac, x0 // clean & invalidate D line / unified line + add x0, x0, x2 + cmp x0, x1 + b.lo 1b + dsb sy + ret +ENDPROC(__flush_dcache_area) |