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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /arch/xtensa/mm/cache.c | |
parent | Initial commit. (diff) | |
download | linux-upstream/5.10.209.tar.xz linux-upstream/5.10.209.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/xtensa/mm/cache.c')
-rw-r--r-- | arch/xtensa/mm/cache.c | 327 |
1 files changed, 327 insertions, 0 deletions
diff --git a/arch/xtensa/mm/cache.c b/arch/xtensa/mm/cache.c new file mode 100644 index 000000000..085b8c77b --- /dev/null +++ b/arch/xtensa/mm/cache.c @@ -0,0 +1,327 @@ +/* + * arch/xtensa/mm/cache.c + * + * 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) 2001-2006 Tensilica Inc. + * + * Chris Zankel <chris@zankel.net> + * Joe Taylor + * Marc Gauthier + * + */ + +#include <linux/init.h> +#include <linux/signal.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/string.h> +#include <linux/types.h> +#include <linux/ptrace.h> +#include <linux/memblock.h> +#include <linux/swap.h> +#include <linux/pagemap.h> +#include <linux/pgtable.h> + +#include <asm/bootparam.h> +#include <asm/mmu_context.h> +#include <asm/tlb.h> +#include <asm/tlbflush.h> +#include <asm/page.h> + +/* + * Note: + * The kernel provides one architecture bit PG_arch_1 in the page flags that + * can be used for cache coherency. + * + * I$-D$ coherency. + * + * The Xtensa architecture doesn't keep the instruction cache coherent with + * the data cache. We use the architecture bit to indicate if the caches + * are coherent. The kernel clears this bit whenever a page is added to the + * page cache. At that time, the caches might not be in sync. We, therefore, + * define this flag as 'clean' if set. + * + * D-cache aliasing. + * + * With cache aliasing, we have to always flush the cache when pages are + * unmapped (see tlb_start_vma(). So, we use this flag to indicate a dirty + * page. + * + * + * + */ + +#if (DCACHE_WAY_SIZE > PAGE_SIZE) +static inline void kmap_invalidate_coherent(struct page *page, + unsigned long vaddr) +{ + if (!DCACHE_ALIAS_EQ(page_to_phys(page), vaddr)) { + unsigned long kvaddr; + + if (!PageHighMem(page)) { + kvaddr = (unsigned long)page_to_virt(page); + + __invalidate_dcache_page(kvaddr); + } else { + kvaddr = TLBTEMP_BASE_1 + + (page_to_phys(page) & DCACHE_ALIAS_MASK); + + preempt_disable(); + __invalidate_dcache_page_alias(kvaddr, + page_to_phys(page)); + preempt_enable(); + } + } +} + +static inline void *coherent_kvaddr(struct page *page, unsigned long base, + unsigned long vaddr, unsigned long *paddr) +{ + if (PageHighMem(page) || !DCACHE_ALIAS_EQ(page_to_phys(page), vaddr)) { + *paddr = page_to_phys(page); + return (void *)(base + (vaddr & DCACHE_ALIAS_MASK)); + } else { + *paddr = 0; + return page_to_virt(page); + } +} + +void clear_user_highpage(struct page *page, unsigned long vaddr) +{ + unsigned long paddr; + void *kvaddr = coherent_kvaddr(page, TLBTEMP_BASE_1, vaddr, &paddr); + + preempt_disable(); + kmap_invalidate_coherent(page, vaddr); + set_bit(PG_arch_1, &page->flags); + clear_page_alias(kvaddr, paddr); + preempt_enable(); +} +EXPORT_SYMBOL(clear_user_highpage); + +void copy_user_highpage(struct page *dst, struct page *src, + unsigned long vaddr, struct vm_area_struct *vma) +{ + unsigned long dst_paddr, src_paddr; + void *dst_vaddr = coherent_kvaddr(dst, TLBTEMP_BASE_1, vaddr, + &dst_paddr); + void *src_vaddr = coherent_kvaddr(src, TLBTEMP_BASE_2, vaddr, + &src_paddr); + + preempt_disable(); + kmap_invalidate_coherent(dst, vaddr); + set_bit(PG_arch_1, &dst->flags); + copy_page_alias(dst_vaddr, src_vaddr, dst_paddr, src_paddr); + preempt_enable(); +} +EXPORT_SYMBOL(copy_user_highpage); + +/* + * Any time the kernel writes to a user page cache page, or it is about to + * read from a page cache page this routine is called. + * + */ + +void flush_dcache_page(struct page *page) +{ + struct address_space *mapping = page_mapping_file(page); + + /* + * If we have a mapping but the page is not mapped to user-space + * yet, we simply mark this page dirty and defer flushing the + * caches until update_mmu(). + */ + + if (mapping && !mapping_mapped(mapping)) { + if (!test_bit(PG_arch_1, &page->flags)) + set_bit(PG_arch_1, &page->flags); + return; + + } else { + + unsigned long phys = page_to_phys(page); + unsigned long temp = page->index << PAGE_SHIFT; + unsigned long alias = !(DCACHE_ALIAS_EQ(temp, phys)); + unsigned long virt; + + /* + * Flush the page in kernel space and user space. + * Note that we can omit that step if aliasing is not + * an issue, but we do have to synchronize I$ and D$ + * if we have a mapping. + */ + + if (!alias && !mapping) + return; + + preempt_disable(); + virt = TLBTEMP_BASE_1 + (phys & DCACHE_ALIAS_MASK); + __flush_invalidate_dcache_page_alias(virt, phys); + + virt = TLBTEMP_BASE_1 + (temp & DCACHE_ALIAS_MASK); + + if (alias) + __flush_invalidate_dcache_page_alias(virt, phys); + + if (mapping) + __invalidate_icache_page_alias(virt, phys); + preempt_enable(); + } + + /* There shouldn't be an entry in the cache for this page anymore. */ +} +EXPORT_SYMBOL(flush_dcache_page); + +/* + * For now, flush the whole cache. FIXME?? + */ + +void local_flush_cache_range(struct vm_area_struct *vma, + unsigned long start, unsigned long end) +{ + __flush_invalidate_dcache_all(); + __invalidate_icache_all(); +} +EXPORT_SYMBOL(local_flush_cache_range); + +/* + * Remove any entry in the cache for this page. + * + * Note that this function is only called for user pages, so use the + * alias versions of the cache flush functions. + */ + +void local_flush_cache_page(struct vm_area_struct *vma, unsigned long address, + unsigned long pfn) +{ + /* Note that we have to use the 'alias' address to avoid multi-hit */ + + unsigned long phys = page_to_phys(pfn_to_page(pfn)); + unsigned long virt = TLBTEMP_BASE_1 + (address & DCACHE_ALIAS_MASK); + + preempt_disable(); + __flush_invalidate_dcache_page_alias(virt, phys); + __invalidate_icache_page_alias(virt, phys); + preempt_enable(); +} +EXPORT_SYMBOL(local_flush_cache_page); + +#endif /* DCACHE_WAY_SIZE > PAGE_SIZE */ + +void +update_mmu_cache(struct vm_area_struct * vma, unsigned long addr, pte_t *ptep) +{ + unsigned long pfn = pte_pfn(*ptep); + struct page *page; + + if (!pfn_valid(pfn)) + return; + + page = pfn_to_page(pfn); + + /* Invalidate old entry in TLBs */ + + flush_tlb_page(vma, addr); + +#if (DCACHE_WAY_SIZE > PAGE_SIZE) + + if (!PageReserved(page) && test_bit(PG_arch_1, &page->flags)) { + unsigned long phys = page_to_phys(page); + unsigned long tmp; + + preempt_disable(); + tmp = TLBTEMP_BASE_1 + (phys & DCACHE_ALIAS_MASK); + __flush_invalidate_dcache_page_alias(tmp, phys); + tmp = TLBTEMP_BASE_1 + (addr & DCACHE_ALIAS_MASK); + __flush_invalidate_dcache_page_alias(tmp, phys); + __invalidate_icache_page_alias(tmp, phys); + preempt_enable(); + + clear_bit(PG_arch_1, &page->flags); + } +#else + if (!PageReserved(page) && !test_bit(PG_arch_1, &page->flags) + && (vma->vm_flags & VM_EXEC) != 0) { + unsigned long paddr = (unsigned long)kmap_atomic(page); + __flush_dcache_page(paddr); + __invalidate_icache_page(paddr); + set_bit(PG_arch_1, &page->flags); + kunmap_atomic((void *)paddr); + } +#endif +} + +/* + * access_process_vm() has called get_user_pages(), which has done a + * flush_dcache_page() on the page. + */ + +#if (DCACHE_WAY_SIZE > PAGE_SIZE) + +void copy_to_user_page(struct vm_area_struct *vma, struct page *page, + unsigned long vaddr, void *dst, const void *src, + unsigned long len) +{ + unsigned long phys = page_to_phys(page); + unsigned long alias = !(DCACHE_ALIAS_EQ(vaddr, phys)); + + /* Flush and invalidate user page if aliased. */ + + if (alias) { + unsigned long t = TLBTEMP_BASE_1 + (vaddr & DCACHE_ALIAS_MASK); + preempt_disable(); + __flush_invalidate_dcache_page_alias(t, phys); + preempt_enable(); + } + + /* Copy data */ + + memcpy(dst, src, len); + + /* + * Flush and invalidate kernel page if aliased and synchronize + * data and instruction caches for executable pages. + */ + + if (alias) { + unsigned long t = TLBTEMP_BASE_1 + (vaddr & DCACHE_ALIAS_MASK); + + preempt_disable(); + __flush_invalidate_dcache_range((unsigned long) dst, len); + if ((vma->vm_flags & VM_EXEC) != 0) + __invalidate_icache_page_alias(t, phys); + preempt_enable(); + + } else if ((vma->vm_flags & VM_EXEC) != 0) { + __flush_dcache_range((unsigned long)dst,len); + __invalidate_icache_range((unsigned long) dst, len); + } +} + +extern void copy_from_user_page(struct vm_area_struct *vma, struct page *page, + unsigned long vaddr, void *dst, const void *src, + unsigned long len) +{ + unsigned long phys = page_to_phys(page); + unsigned long alias = !(DCACHE_ALIAS_EQ(vaddr, phys)); + + /* + * Flush user page if aliased. + * (Note: a simply flush would be sufficient) + */ + + if (alias) { + unsigned long t = TLBTEMP_BASE_1 + (vaddr & DCACHE_ALIAS_MASK); + preempt_disable(); + __flush_invalidate_dcache_page_alias(t, phys); + preempt_enable(); + } + + memcpy(dst, src, len); +} + +#endif |