/*
* arch/xtensa/mm/misc.S
*
* Miscellaneous assembly functions.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2001 - 2007 Tensilica Inc.
*
* Chris Zankel <chris@zankel.net>
*/
#include <linux/linkage.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/asmmacro.h>
#include <asm/cacheasm.h>
#include <asm/tlbflush.h>
/*
* clear_page and clear_user_page are the same for non-cache-aliased configs.
*
* clear_page (unsigned long page)
* a2
*/
ENTRY(clear_page)
entry a1, 16
movi a3, 0
__loopi a2, a7, PAGE_SIZE, 32
s32i a3, a2, 0
s32i a3, a2, 4
s32i a3, a2, 8
s32i a3, a2, 12
s32i a3, a2, 16
s32i a3, a2, 20
s32i a3, a2, 24
s32i a3, a2, 28
__endla a2, a7, 32
retw
ENDPROC(clear_page)
/*
* copy_page and copy_user_page are the same for non-cache-aliased configs.
*
* copy_page (void *to, void *from)
* a2 a3
*/
ENTRY(copy_page)
entry a1, 16
__loopi a2, a4, PAGE_SIZE, 32
l32i a8, a3, 0
l32i a9, a3, 4
s32i a8, a2, 0
s32i a9, a2, 4
l32i a8, a3, 8
l32i a9, a3, 12
s32i a8, a2, 8
s32i a9, a2, 12
l32i a8, a3, 16
l32i a9, a3, 20
s32i a8, a2, 16
s32i a9, a2, 20
l32i a8, a3, 24
l32i a9, a3, 28
s32i a8, a2, 24
s32i a9, a2, 28
addi a2, a2, 32
addi a3, a3, 32
__endl a2, a4
retw
ENDPROC(copy_page)
#ifdef CONFIG_MMU
/*
* If we have to deal with cache aliasing, we use temporary memory mappings
* to ensure that the source and destination pages have the same color as
* the virtual address. We use way 0 and 1 for temporary mappings in such cases.
*
* The temporary DTLB entries shouldn't be flushed by interrupts, but are
* flushed by preemptive task switches. Special code in the
* fast_second_level_miss handler re-established the temporary mapping.
* It requires that the PPNs for the destination and source addresses are
* in a6, and a7, respectively.
*/
/* TLB miss exceptions are treated special in the following region */
ENTRY(__tlbtemp_mapping_start)
#if (DCACHE_WAY_SIZE > PAGE_SIZE)
/*
* clear_page_alias(void *addr, unsigned long paddr)
* a2 a3
*/
ENTRY(clear_page_alias)
entry a1, 32
/* Skip setting up a temporary DTLB if not aliased low page. */
movi a5, PAGE_OFFSET
movi a6, 0
beqz a3, 1f
/* Setup a temporary DTLB for the addr. */
addi a6, a3, (PAGE_KERNEL | _PAGE_HW_WRITE)
mov a4, a2
wdtlb a6, a2
dsync
1: movi a3, 0
__loopi a2, a7, PAGE_SIZE, 32
s32i a3, a2, 0
s32i a3, a2, 4
s32i a3, a2, 8
s32i a3, a2, 12
s32i a3, a2, 16
s32i a3, a2, 20
s32i a3, a2, 24
s32i a3, a2, 28
__endla a2, a7, 32
bnez a6, 1f
retw
/* We need to invalidate the temporary idtlb entry, if any. */
1: idtlb a4
dsync
retw
ENDPROC(clear_page_alias)
/*
* copy_page_alias(void *to, void *from,
* a2 a3
* unsigned long to_paddr, unsigned long from_paddr)
* a4 a5
*/
ENTRY(copy_page_alias)
entry a1, 32
/* Skip setting up a temporary DTLB for destination if not aliased. */
movi a6, 0
movi a7, 0
beqz a4, 1f
/* Setup a temporary DTLB for destination. */
addi a6, a4, (PAGE_KERNEL | _PAGE_HW_WRITE)
wdtlb a6, a2
dsync
/* Skip setting up a temporary DTLB for source if not aliased. */
1: beqz a5, 1f
/* Setup a temporary DTLB for source. */
addi a7, a5, PAGE_KERNEL
addi a8, a3, 1 # way1
wdtlb a7, a8
dsync
1: __loopi a2, a4, PAGE_SIZE, 32
l32i a8, a3, 0
l32i a9, a3, 4
s32i a8, a2, 0
s32i a9, a2, 4
l32i a8, a3, 8
l32i a9, a3, 12
s32i a8, a2, 8
s32i a9, a2, 12
l32i a8, a3, 16
l32i a9, a3, 20
s32i a8, a2, 16
s32i a9, a2, 20
l32i a8, a3, 24
l32i a9, a3, 28
s32i a8, a2, 24
s32i a9, a2, 28
addi a2, a2, 32
addi a3, a3, 32
__endl a2, a4
/* We need to invalidate any temporary mapping! */
bnez a6, 1f
bnez a7, 2f
retw
1: addi a2, a2, -PAGE_SIZE
idtlb a2
dsync
bnez a7, 2f
retw
2: addi a3, a3, -PAGE_SIZE+1
idtlb a3
dsync
retw
ENDPROC(copy_page_alias)
#endif
#if (DCACHE_WAY_SIZE > PAGE_SIZE)
/*
* void __flush_invalidate_dcache_page_alias (addr, phys)
* a2 a3
*/
ENTRY(__flush_invalidate_dcache_page_alias)
entry sp, 16
movi a7, 0 # required for exception handler
addi a6, a3, (PAGE_KERNEL | _PAGE_HW_WRITE)
mov a4, a2
wdtlb a6, a2
dsync
___flush_invalidate_dcache_page a2 a3
idtlb a4
dsync
retw
ENDPROC(__flush_invalidate_dcache_page_alias)
/*
* void __invalidate_dcache_page_alias (addr, phys)
* a2 a3
*/
ENTRY(__invalidate_dcache_page_alias)
entry sp, 16
movi a7, 0 # required for exception handler
addi a6, a3, (PAGE_KERNEL | _PAGE_HW_WRITE)
mov a4, a2
wdtlb a6, a2
dsync
___invalidate_dcache_page a2 a3
idtlb a4
dsync
retw
ENDPROC(__invalidate_dcache_page_alias)
#endif
ENTRY(__tlbtemp_mapping_itlb)
#if (ICACHE_WAY_SIZE > PAGE_SIZE)
ENTRY(__invalidate_icache_page_alias)
entry sp, 16
addi a6, a3, (PAGE_KERNEL_EXEC | _PAGE_HW_WRITE)
mov a4, a2
witlb a6, a2
isync
___invalidate_icache_page a2 a3
iitlb a4
isync
retw
ENDPROC(__invalidate_icache_page_alias)
#endif
/* End of special treatment in tlb miss exception */
ENTRY(__tlbtemp_mapping_end)
#endif /* CONFIG_MMU
/*
* void __invalidate_icache_page(ulong start)
*/
ENTRY(__invalidate_icache_page)
entry sp, 16
___invalidate_icache_page a2 a3
isync
retw
ENDPROC(__invalidate_icache_page)
/*
* void __invalidate_dcache_page(ulong start)
*/
ENTRY(__invalidate_dcache_page)
entry sp, 16
___invalidate_dcache_page a2 a3
dsync
retw
ENDPROC(__invalidate_dcache_page)
/*
* void __flush_invalidate_dcache_page(ulong start)
*/
ENTRY(__flush_invalidate_dcache_page)
entry sp, 16
___flush_invalidate_dcache_page a2 a3
dsync
retw
ENDPROC(__flush_invalidate_dcache_page)
/*
* void __flush_dcache_page(ulong start)
*/
ENTRY(__flush_dcache_page)
entry sp, 16
___flush_dcache_page a2 a3
dsync
retw
ENDPROC(__flush_dcache_page)
/*
* void __invalidate_icache_range(ulong start, ulong size)
*/
ENTRY(__invalidate_icache_range)
entry sp, 16
___invalidate_icache_range a2 a3 a4
isync
retw
ENDPROC(__invalidate_icache_range)
/*
* void __flush_invalidate_dcache_range(ulong start, ulong size)
*/
ENTRY(__flush_invalidate_dcache_range)
entry sp, 16
___flush_invalidate_dcache_range a2 a3 a4
dsync
retw
ENDPROC(__flush_invalidate_dcache_range)
/*
* void _flush_dcache_range(ulong start, ulong size)
*/
ENTRY(__flush_dcache_range)
entry sp, 16
___flush_dcache_range a2 a3 a4
dsync
retw
ENDPROC(__flush_dcache_range)
/*
* void _invalidate_dcache_range(ulong start, ulong size)
*/
ENTRY(__invalidate_dcache_range)
entry sp, 16
___invalidate_dcache_range a2 a3 a4
retw
ENDPROC(__invalidate_dcache_range)
/*
* void _invalidate_icache_all(void)
*/
ENTRY(__invalidate_icache_all)
entry sp, 16
___invalidate_icache_all a2 a3
isync
retw
ENDPROC(__invalidate_icache_all)
/*
* void _flush_invalidate_dcache_all(void)
*/
ENTRY(__flush_invalidate_dcache_all)
entry sp, 16
___flush_invalidate_dcache_all a2 a3
dsync
retw
ENDPROC(__flush_invalidate_dcache_all)
/*
* void _invalidate_dcache_all(void)
*/
ENTRY(__invalidate_dcache_all)
entry sp, 16
___invalidate_dcache_all a2 a3
dsync
retw
ENDPROC(__invalidate_dcache_all)
