xref: /OK3568_Linux_fs/kernel/arch/openrisc/mm/cache.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * OpenRISC cache.c
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * Linux architectural port borrowing liberally from similar works of
6*4882a593Smuzhiyun  * others.  All original copyrights apply as per the original source
7*4882a593Smuzhiyun  * declaration.
8*4882a593Smuzhiyun  *
9*4882a593Smuzhiyun  * Modifications for the OpenRISC architecture:
10*4882a593Smuzhiyun  * Copyright (C) 2015 Jan Henrik Weinstock <jan.weinstock@rwth-aachen.de>
11*4882a593Smuzhiyun  */
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun #include <asm/spr.h>
14*4882a593Smuzhiyun #include <asm/spr_defs.h>
15*4882a593Smuzhiyun #include <asm/cache.h>
16*4882a593Smuzhiyun #include <asm/cacheflush.h>
17*4882a593Smuzhiyun #include <asm/tlbflush.h>
18*4882a593Smuzhiyun 
cache_loop(struct page * page,const unsigned int reg)19*4882a593Smuzhiyun static __always_inline void cache_loop(struct page *page, const unsigned int reg)
20*4882a593Smuzhiyun {
21*4882a593Smuzhiyun 	unsigned long paddr = page_to_pfn(page) << PAGE_SHIFT;
22*4882a593Smuzhiyun 	unsigned long line = paddr & ~(L1_CACHE_BYTES - 1);
23*4882a593Smuzhiyun 
24*4882a593Smuzhiyun 	while (line < paddr + PAGE_SIZE) {
25*4882a593Smuzhiyun 		mtspr(reg, line);
26*4882a593Smuzhiyun 		line += L1_CACHE_BYTES;
27*4882a593Smuzhiyun 	}
28*4882a593Smuzhiyun }
29*4882a593Smuzhiyun 
local_dcache_page_flush(struct page * page)30*4882a593Smuzhiyun void local_dcache_page_flush(struct page *page)
31*4882a593Smuzhiyun {
32*4882a593Smuzhiyun 	cache_loop(page, SPR_DCBFR);
33*4882a593Smuzhiyun }
34*4882a593Smuzhiyun EXPORT_SYMBOL(local_dcache_page_flush);
35*4882a593Smuzhiyun 
local_icache_page_inv(struct page * page)36*4882a593Smuzhiyun void local_icache_page_inv(struct page *page)
37*4882a593Smuzhiyun {
38*4882a593Smuzhiyun 	cache_loop(page, SPR_ICBIR);
39*4882a593Smuzhiyun }
40*4882a593Smuzhiyun EXPORT_SYMBOL(local_icache_page_inv);
41*4882a593Smuzhiyun 
update_cache(struct vm_area_struct * vma,unsigned long address,pte_t * pte)42*4882a593Smuzhiyun void update_cache(struct vm_area_struct *vma, unsigned long address,
43*4882a593Smuzhiyun 	pte_t *pte)
44*4882a593Smuzhiyun {
45*4882a593Smuzhiyun 	unsigned long pfn = pte_val(*pte) >> PAGE_SHIFT;
46*4882a593Smuzhiyun 	struct page *page = pfn_to_page(pfn);
47*4882a593Smuzhiyun 	int dirty = !test_and_set_bit(PG_dc_clean, &page->flags);
48*4882a593Smuzhiyun 
49*4882a593Smuzhiyun 	/*
50*4882a593Smuzhiyun 	 * Since icaches do not snoop for updated data on OpenRISC, we
51*4882a593Smuzhiyun 	 * must write back and invalidate any dirty pages manually. We
52*4882a593Smuzhiyun 	 * can skip data pages, since they will not end up in icaches.
53*4882a593Smuzhiyun 	 */
54*4882a593Smuzhiyun 	if ((vma->vm_flags & VM_EXEC) && dirty)
55*4882a593Smuzhiyun 		sync_icache_dcache(page);
56*4882a593Smuzhiyun }
57*4882a593Smuzhiyun 
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