1 files changed, 68 insertions, 9 deletions

diff --git a/arch/xtensa/mm/cache.c b/arch/xtensa/mm/cache.c
index 63cbb867dadd..d75aa1476da7 100644
--- a/arch/xtensa/mm/cache.c
+++ b/arch/xtensa/mm/cache.c
@@ -59,9 +59,68 @@
  *
  */
 
-#if (DCACHE_WAY_SIZE > PAGE_SIZE) && defined(CONFIG_HIGHMEM)
-#error "HIGHMEM is not supported on cores with aliasing cache."
-#endif
+#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);
+
+                        __invalidate_dcache_page_alias(kvaddr,
+                                                       page_to_phys(page));
+                }
+        }
+}
+
+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);
+
+        pagefault_disable();
+        kmap_invalidate_coherent(page, vaddr);
+        set_bit(PG_arch_1, &page->flags);
+        clear_page_alias(kvaddr, paddr);
+        pagefault_enable();
+}
+
+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);
+
+        pagefault_disable();
+        kmap_invalidate_coherent(dst, vaddr);
+        set_bit(PG_arch_1, &dst->flags);
+        copy_page_alias(dst_vaddr, src_vaddr, dst_paddr, src_paddr);
+        pagefault_enable();
+}
+
+#endif /* DCACHE_WAY_SIZE > PAGE_SIZE */
 
 #if (DCACHE_WAY_SIZE > PAGE_SIZE) && XCHAL_DCACHE_IS_WRITEBACK
 
@@ -103,7 +162,8 @@ void flush_dcache_page(struct page *page)
                 if (!alias && !mapping)
                         return;
 
-                __flush_invalidate_dcache_page((long)page_address(page));
+                virt = TLBTEMP_BASE_1 + (phys & DCACHE_ALIAS_MASK);
+                __flush_invalidate_dcache_page_alias(virt, phys);
 
                 virt = TLBTEMP_BASE_1 + (temp & DCACHE_ALIAS_MASK);
 
@@ -168,13 +228,12 @@ update_mmu_cache(struct vm_area_struct * vma, unsigned long addr, pte_t *ptep)
 #if (DCACHE_WAY_SIZE > PAGE_SIZE) && XCHAL_DCACHE_IS_WRITEBACK
 
         if (!PageReserved(page) && test_bit(PG_arch_1, &page->flags)) {
-
-                unsigned long paddr = (unsigned long) page_address(page);
                 unsigned long phys = page_to_phys(page);
-                unsigned long tmp = TLBTEMP_BASE_1 + (addr & DCACHE_ALIAS_MASK);
-
-                __flush_invalidate_dcache_page(paddr);
+                unsigned long tmp;
 
+                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);